Best Camera for Backpacking: Three Top Choices for Compact Digital Cameras

Pentax Optio W90 Digital Camera (5 out of 5)The absolute best camera for backpacking might just be a breakthrough offering from Pentax. For the price ($200 on Amazon.com), the dynamic, waterproof, and extremely durable Pentax Optio W90 is jam packed with features well suited for the backpacker. Beginning with its light weight (5.8 ounces) and compact dimensions (4.2 x 2.3 x 1 inches), this sleek device is small enough to have at the ready in a pocket the whole time you're hiking. Since it powers up in 1.3 seconds and there's only a .3 second shutter lag, you can snap any interesting woodland creature that wanders into focus too. With a 5x digital zoom and 12.1 megapixel capacity, you can convince your friends that the stunningly clear 300 pound grizzly bear was a lot closer than it actually was. What's more, you don't have to worry about rain, sleet, or snow because this camera is waterproof (usually when "W" is in a model name, that's what it means) up to 20 feet. So that means you can take plenty of great underwater shots with it too.It's shockproof so long as it's no longer than four feet and don't worry about the dust, desert scramblers. It's really easy to use if you're new to the digital photography world, taking great pictures no matter what skill level you're at along with high quality HD to boot (complete with an editing feature built into the camera). Incidentally, if you're in the market for one, check out The Backpacker's Top Ratings for Handheld GPS. Back to the Pentax W90; for close ups, it has a digital microscope mode to capture a subject that is only a mere centimeter away from the lens. What they deem an Advanced Pixel Track Shake Reduction translates to the user taking clear and crisp pictures while shivering, shaking, or even on a moving surface (or hanging from a rope, climbers). It will operate at 14 and 104 degrees Fahrenheit and everything in between. Finally, you can get it in yellow so that after you're ready to hit the trail again after a break, it sticks out like a sore thumb during your gear check.Olympus Stylus Tough-8010 (5 out of 5)Designed with adventurous souls in mind, the Stylus Tough-8010 out does the other offerings on the list in terms of its rugged frame that can take a 6.6 ft drop and withstand a 220 lb. crushing blow; so it's the optimum choice for the clumsy and those really hard on gear. You can confidently take pictures at deeper depths (33 feet) also. But the rugged design doesn't diminish the ability of this high resolution 14 megapixel to create stunning and vividly detailed photos. The anti-glare 2.7" LCD gives you a nice and wide viewing angle and the 5x optical zoom (that doesn't protrude) can get you really close to wildlife and you can also shoot HD video with ease. This model retails for around $250 on Amazon.com. It has 29 different shooting modes but the Auto option will identify your target and make all the adjustments for you. Dual Image Stabilization combined with ISO sensitivity and a super-quick shutter speed captures those moving objects. The Li-ion rechargeable battery has a decent life at about 200 pictures. This model's one big drawback is that it's slow starting up, and slower between pictures. But if it's landscapes it's great for the money. The Canon PowerShot D10reviewed in the second article in this series is quicker and the image quality is a little better too.But it's also worthy of noting that although the Stylus 1030SW has been discontinued (or what they annoyingly deem as "archived" on the company website) you can still find this outstanding, smash-proof offering on the Web (Amazon has it listed for $420). This Stylus model topped Backpacker Magazine's best gear list in 2009. If they said it's the best camera for backpacking, then it certainly is a well-regarded item to put on your gear list.Nikon Coolpix P6000 Camera – Great Photos and Geotagging TooContinuing on with our choices for the best camera to take backpacking, we move on to Nikon now. The hardy, feature-laden Coolpix P6000 was designed with the rugged backpacker in mind because first of all, it's designed to withstand a pounding either rattling around in the pack or even dropping it (although they do give a four foot maximum). The internal GPS geotags every picture you take with a digital stamp so you know exactly where it was taken. Then, when you return from a trip, it's a breeze to download all your pictures to Google Earth, the post-a-trip feature on Backpacker.com, or Nikon Picturetown. It's a fantastic way to photo journal every trip you take by integrating the pics with maps. Even when the camera is off, it's little electronic brain updates and locks your GPS position. You might want to take a look at this great review of the Coolpix 7000 too, for comparative purposes.This compact and lightweight (8.5 ounces) digital dynamo has a 13.5 megapixel capacity with a 2.7-inch LCD screen that takes stunning pictures that capture the subtleties and shadowy features of the natural world better than most point and shoot offerings. To zero in on distant wildlife, it has a 4x zoom optical lens that never protrudes from the camera because it's internally stacked. When the sun is too bright, you have the option of using the additional viewfinder to frame your images. From those mountain peaks, treasured by many backpackers, this camera has a mode for panorama stitching mode to recreate that breathtaking view. The only downside is the 11 hour battery life you get with the rechargeable cell battery. The experts at Backpacker Magazine gave this the Editor's Choice Award for 2009 which speaks volumes about its prowess in the field. At the time of this writing, it's on sale for $650 on Amazon.com. But you can find it for a lot cheaper than that with a little searching of your own.So there you have it, three models you can't go wrong with that will all withstand any conditions you might encounter, but they also offer some different features that might appeal to you. So get out there and enjoy the wild reaches of this world to get in tune with your true self. And take lots of pictures to remind yourself of that feeling back in this silly world where having to go to jobs is the best we could come up with in 4000 years.This post is part of the series: Best Compact Digital Point-and-Shoots for Outdoor Enthusiasts

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Woman Shares Gruesome Pics Showing What Years of Gel Manicures Have Done to Her Nails  and It'll Pro
Woman Shares Gruesome Pics Showing What Years of Gel Manicures Have Done to Her Nails and It'll Pro
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2021 06 25
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Formation of Printable Granular and Colloidal Chains Through Capillary Effects and Dielectrophoresis
Formation of Printable Granular and Colloidal Chains Through Capillary Effects and Dielectrophoresis
One-dimensional conductive particle assembly holds promise for a variety of practical applications, in particular for a new generation of electronic devices. However, synthesis of such chains with programmable shapes outside a liquid environment has proven difficult. Here we report a route to simply 'pull' flexible granular and colloidal chains out of a dispersion by combining field-directed assembly and capillary effects. These chains are automatically stabilized by liquid bridges formed between adjacent particles, without the need for continuous energy input or special particle functionalization. They can further be deposited onto any surface and form desired conductive patterns, potentially applicable to the manufacturing of simple electronic circuits. Various aspects of our route, including the role of particle size and the voltages needed, are studied in detail. Looking towards practical applications, we also present the possibility of two-dimensional writing, rapid solidification of chains and methods to scale up chain production.The experimental set-up consisted of a signal generator (SDG1025 Siglent), a high-voltage bipolar amplifier (10HVA24-BP1 HVP), –– motorized translation stage (MTS25-Z8 Thorlabs), a digital microscope (AM7115 Dino-Lite) and a PC for collecting images. The signal electrode for pulling out the particles from a dispersion was made of a thin aluminium wire attached to another motorized translation stage for controlling the pulling rate.Silicone oils (Dow Corning 200 with kinematic viscosity 100 cSt; electric conductivity
2021 06 25
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Biomimetic Virus-based Colourimetric Sensors
Biomimetic Virus-based Colourimetric Sensors
Many materials in nature change colours in response to stimuli, making them attractive for use as sensor platform. However, both natural materials and their synthetic analogues lack selectivity towards specific chemicals, and introducing such selectivity remains a challenge. Here we report the self-assembly of genetically engineered viruses (M13 phage) into target-specific, colourimetric biosensors. The sensors are composed of phage-bundle nanostructures and exhibit viewing-angle independent colour, similar to collagen structures in turkey skin. On exposure to various volatile organic chemicals, the structures rapidly swell and undergo distinct colour changes. Furthermore, sensors composed of phage displaying trinitrotoluene (TNT)-binding peptide motifs identified from a phage display selectively distinguish TNT down to 300 p.p.b. over similarly structured chemicals. Our tunable, colourimetric sensors can be useful for the detection of a variety of harmful toxicants and pathogens to protect human health and national security.Our group identified a consensus TNT-binding peptide sequence (WHWQ) using phage display with a commercially available 12mer linear peptide library (Ph.D.-12). To incorporate the TNT-binding peptide, we genetically engineered the M13 phage's major coat proteins (pVIII). The desired peptide sequences were inserted between the first and the sixth amino acids of the amino terminus of wild-type pVIII, replacing residues 2–5 (Ala--Pro to Ala-()-Pro). To incorporate the most stable phage to carry the consensus TNT-binding peptide (WHWQ) identified by phage display, we designed a partial library with sequence of the form ADP using the primer: 5′-ATATATCTGCAGCCCGCAAAAGCG GCCTTTAACTCCC-3′ and the primer 5′-GCTGTCTTTCGCTGC AGAGGGTG-3′ to linearize the vector (=A/C/G/T and =G/T). To incorporate the gene sequences, PCR amplification was performed using Phusion DNA Polymerase, two primers (insertion and linearization) and an M13KE vector with an engineered I site as the template. The obtained product was purified on an agarose gel, eluted by spin column purification, digested with I enzyme and recircularized by an overnight ligation at 16 °C with T4 DNA ligase. The ligated DNA vector was transformed into XL1-Blue electroporation competent bacteria and the amplified plasmid sequence was verified at the University of California, Berkeley, DNA sequencing facility. The pVIII library was screened against TNT and the resulting sequences were tested for stability after large-scale amplification. The library member, ADDWHWQEGDP, was finally chosen to create our TNT–Phage litmus sensors. Alanine-substituted control phage (WAW, AHW and WHA) sequences were synthesized by site-directed mutagenesis of the WHW phage. Using similar genetic engineering approaches, we constructed 4E phage as a control. The constructed phages were amplified using bacterial cultures and purified through standard polyethylene glycol precipitation. The phage solution was further purified by filtration through 0.45 μm pore size membranes. To verify phage stability, DNA sequences were confirmed at each step of the amplification.We created the phage self-assembled colour band patterns using a simple pulling method. The colours of the assembled structures were varied by controlling the pulling speed between 20 and 80 μm min. We constructed a home-built phage deposition apparatus by modifying a syringe pump. We programmed software using C to control the motor speed (between 0.1 μm min and 30 mm min) through an RS232C cable. For preparing Phage litmus matrices, we used 6 mg ml 4E phage suspensions in Tris-buffered saline (12.5 mM Tris and 37.5 mM NaCl, pH 7.5) or 2.4 mg ml WHW-phage suspensions in DI water. A spectrum of coloured bands (each band was obtained at a different pulling speed) was clearly perceptible when the matrices were deposited on gold-coated Si wafers.Fresh turkey head samples were donated from a local turkey farm (Pitman Farms, Sanger, CA, USA). The heads were obtained through overnight delivery immediately after they were slaughtered. The fresh turkey skin samples were immediately taken and processed for optical microscopy and transmission electron microscopy. For histology, 0.5 × 1 cm turkey skin samples were soaked in 20% sucrose in PBS for 2 h, embedded in OCT Compound (Sakura, Torrance, CA, USA), cryosectioned at 5 μm thickness (Shandon Cryostat, Asheville, NC) and stained with Masson's trichrome. Images were collected using an IX71 Microscope (Olympus, Tokyo, Japan). Transmission electron microscopy samples were fixed with 2% glutaraldehyde in 0.1 M sodium cacodylate (pH 7.2) for 1 h, post-fixed with 1% osmium tetroxide in 0.1 M sodium cacodylate (pH 7.2) and rinsed three times with sodium cacodylate (pH 7.2). Dehydration was done using a graded ethanol series (20, 40, 60, 80, 100 and 100%) followed by step-wise infiltration with epon-araldite resin (two parts acetone/one part resin for 1 h, one part acetone/one part resin for 1 h, one part acetone/two parts resin for 1 h, 100% resin for 1 h, 100% resin overnight, 100% resin with benzyl dimethylamine (BDMA) for 1 h) and heat polymerized in a 60 °C oven. Sample blocks were sectioned at 90 nm using a Leica EM UC6 microtome (Leica Microsystems Inc., Buffalo Grove, IL 60089, USA). Grids were stained with 2% uranyl acetate and Reynolds' lead citrate. Imaging was done using a FEI Tecnai 12 transmission electron microscope (FEI, Hillsboro, OR 97124, USA).AFM images were collected using an MFP3D AFM (Asylum Research, Santa Barbara, CA) and analysed using Igor Pro 6.0 (WaveMetrics, Inc., Lake Oswego, OR) and Asylum software package (Asylum Research). All images were taken in tapping mode with a tip spring constant of 2 N m. The probe tips (Ted Pella, Inc., Redding, CA) were made of silicon with a 10-nm radius. The humidity experiments were carried out in a closed liquid cell. We injected a fixed quantity of DI water to control the humidity. FFT analysis of AFM cross-sectional height profiles was used to determine the periodicity of the self-assembled nanofilament structures within the Phage litmus matrices. Numerical computation of the Fourier transform was done with a 2D FFT algorithm in OriginPro 8 (Origin Lab Corp., Northampton, MA) and imageJ v1.44p (National Institutes of Health, USA). We calculated the Fourier power spectra expressed in spatial frequency (μm) from the AFM images.Phage litmus matrices were illuminated by a white light source of a Xenon lamp (X-Cite, Exfo, Mississauga, Canada) and the reflected spectra were obtained using a fibre optic spectrophotometer (USB4000, Ocean Optics, Dunedin, FL) through a Y-shaped bifurcated optical fibre (). An optical fibre fixed on an –– stage was positioned normal to the Phage litmus surface and perpendicular to the scanning direction. Reflectance was measured using a gold-coated Si wafer as a reference. The humidity experiments were performed in a closed glove box (Plas Labs, Inc., Lansing, MI). The humidity was controlled by DI water and monitored using a hygrometer (VWR International Inc., West Chester, PA).To characterize the reflectance spectra of the Phage litmus under omnidirectional illumination, we lit a box coated with aluminium foil with a lamp (Incandescent Light, 150 W, DWC Sylvania, USA; ). We characterized the reflectance spectra while rotating the substrate between 10° and 90° from horizontal. A gold-coated Si wafer was used as a reference.To characterize the swelling behaviour of the Phage litmus, we performed GISAXS experiments before and during exposure to humidity (3 ml of DI water in a closed chamber). The GISAXS data were collected at the beamline 7.3.3 at the Advanced Light Source at Lawrence Berkeley National Laboratory. X-rays with a wavelength of 1.23984 Å (10 keV) were used, and the scattering spectra were collected on an ADSC Quantum 4 μm CCD detector with an active area of 188 × 188 mm (2,304 × 2,304 pixels). The scattering profiles were obtained after a 60-s collection time by integrating the 2D scattering pattern. The sample to detector distance was 1.84791, m and the incidence angle was 0.14°. Line-averaged intensities were reported as versus , where =(4/) × sin(/2), was the wavelength of incident X-rays and was the scattering angle.A home-built sensing and analysis system was developed for real-time chemical sensing. The equipment setup consisted of a gas chamber with an optical opening where a digital microscope (Celestron LLC, Torrance, CA) was attached to monitor the colour of the Phage litmus. The chamber with the Phage litmus inside was positioned on top of a heat block to control the temperature of the chamber. A MATLAB programme (Mathworks Inc., Natick, MA) was run on a PC to control the camera settings, to perform real-time readout and processing of the captured images and to display the real-time RGB data. First, the automatic gain of the digital microscope was turned to manual mode and a fixed gain was retained to prevent unwanted automatic compensation of brightness. The number of regions of interest, usually matching the number of different colour bands on the Phage litmus, was input by keyboard. Next, the specific regions to compare were selected from the first image (reference image) by mouse input. The subsequent images were taken and saved according to a pre-set frame rate (usually every 5 s). The change of the average RGB values with respect to the reference image for each region of interest was calculated and displayed on a graph in real time. We provide typical code from which we performed our experiments in . The vapour-phase experiments were performed by injection of a volume of solvent needed to achieve 300 p.p.m. concentration into a small container inside the chamber through an inlet tube. For explosive exposure experiments, we put excess amounts of each explosive crystal (200 mg) in a sealed chamber (20 ml) and controlled the vapour pressures by temperature. We obtained the concentration of all compounds based on the vapour pressure at each temperature with the assumption of vapour ideality. The vapour pressure of TNT, DNT and MNT was obtained from previously reported values. To collect the data at saturated conditions, we held the Phage litmus in the sealed chamber for 30 min and then obtained corresponding sensing results. To test the specificity of our TNT–Phage litmus sensor towards interfering molecules, experiments were performed in mixed vapours of MNT, DNT and TNT. First, we put the small sealed chambers (1 ml) containing excess amounts of each explosive crystal (200 mg) in a large chamber with the phage litmus. Next, we exposed the chambers to MNT, DNT and TNT vapours sequentially using needles to open each small chamber (). A similar setup was used to perform the same experiments in a background of ethanol vapour (). We performed the control experiments using a 4E–Phage litmus sensor ().Surface plasmon resonance analyses were performed using the Kretschmann optical configuration. A tungsten halogen lamp with a multiwavelength light source was used and a polarizer was positioned on the input path of the light for transverse magnetic fields. The prism coupler and the Phage litmus were mounted on an stage. We made an enclosed cell of 100 μl using polydimethylsiloxane (PDMS) moulds. Flow of solution to the cell was implemented using 1 mm internal diameter tube. We injected 1 ml of solution into the cell at a flow rate of 50 μl min. The outflow from the cell was carried through to a reservoir. The reflected spectrum was measured by a fibre optic spectrometer (USB4000-ultraviolet visible, Ocean Optics) and data acquisition was performed using a homemade LabVIEW programme (LabVIEW 2009, National Instrument, Austin, TX). The surface plasmon resonance spectrum was calculated from linearly polarized light parallel/perpendicular to the incidence plane (TM/TE configuration).iColour analyser is an iOS 5 application software built using the Xcode programming language (Xcode 4.2, Apple Inc., Cupertino, CA) and designed for the iPhone (Apple Inc, compatible with the iPod and iPad). This software has been built to analyse colourimetric changes of the RGB components from a Phage litmus in a systematic manner using a handheld device (). As demonstrated in this paper, the RGB colour components and their changes from the Phage litmus can be linked to specific responses from target molecules. The iColour analyser workflow is constituted of different parts (), as follows:: A channel type (picker) is displayed to choose an analysis mode: single or double channel. Single-channel mode samples from one to five colour matrices of a Phage litmus labelled as S1–S5. The results display one to five different colour matrix RGB components in a bar graph and their values on an 8-bit level. Double-channel mode allows for colour comparison analysis between a reference Phage litmus (before exposure to chemical) and the sample Phage litmus (after exposure to chemical) through comparison between one and five matrices. The RGB values displayed will be the difference between the RGB values of the sample and the reference.: Once the user clicks on the single button of this application, the iPhone takes a picture of the Phage litmus. One can resize and crop the picture of the Phage litmus sample to precisely obtain the target area to analyse.: Once the picture is taken, its central area is cropped and displayed. The picture is converted into a matrix containing the RGB and intensity values of each pixel. The vector data from the iPhone digital camera CCD (Omnivision OV5650, Santa Clara, CA) is processed to get the average of the RGB values from 2,592 × 1,944 pixels over the different areas selected by the user. An analysis table displays the RGB component intensity values and their s.d. An analysis graph will display the RGB values obtained from the sample. The 'average' picture displays a synthesized picture made from either the average RGB values in the case of the single analysis mode, or the difference between the average RGB values of the Phage litmus and its reference in the case of the double comparison mode. After displaying the analysis data and the date and time, a screenshot of the interface is saved in the picture browser of the iPhone and can be transferred easily to any computer through e-mail. In this work, for display purposes, the colour ranges of images are expanded from 5- to 8 bits per colour (RGB colour ranges of 0–31 expanded to 0–255).
2021 06 25
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The Advantages of Digital Microscopes
The Advantages of Digital Microscopes
Digital microscopes are a marvel of modern science. A digital microscope consists of a regular microscope with a digital camera built into it. The images seen through a digital microscope can be projected to a computer monitor and saved on a computer file. A digital microscope is perfect for education because it lets many people view the specimen at once. The data saving capabilities of a digital microscope make it a great tool for research. A digital microscope is a microscope that contains a tiny digital camera and is connected to a computer. Most digital microscopes connect to computers via a USB port. Once the microscope is connected to the computer, the images seen through the microscope's eyepiece can be shown on the computer's monitor and saved on the hard drive for future use. Images can be printed if the computer is equipped with a digital printer. Digital microscopes are great for educational purposes. Many students can view the specimen at once when the camera is hooked up to a computer. This saves time and ensures that all of the students will get to see the same specimen. People can save images viewed through digital microscopes to computers, allowing them to access the image later. This is perfect for a school setting as it lets students recall the image if they need to later describe it or write about its details. Scientific researchers benefit greatly from digital microscopes. They are able to save and print images from the microscope, allowing for close examination. When the images seen through a digital microscope are viewed on a computer screen, it enables several researchers to examine the image at once. There are several different models of digital microscopes. Some have one eyepiece like most conventional microscopes. A handful of models are stereo microscopes , meaning that they have two eyepieces. All digital microscopes have numerous features that make them great tools for education and research.
2021 06 25
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The Advantages of Digital Microscopes
The Advantages of Digital Microscopes
Digital microscopes are a marvel of modern science. A digital microscope consists of a regular microscope with a digital camera built into it. The images seen through a digital microscope can be projected to a computer monitor and saved on a computer file. A digital microscope is perfect for education because it lets many people view the specimen at once. The data saving capabilities of a digital microscope make it a great tool for research. A digital microscope is a microscope that contains a tiny digital camera and is connected to a computer. Most digital microscopes connect to computers via a USB port. Once the microscope is connected to the computer, the images seen through the microscope's eyepiece can be shown on the computer's monitor and saved on the hard drive for future use. Images can be printed if the computer is equipped with a digital printer. Digital microscopes are great for educational purposes. Many students can view the specimen at once when the camera is hooked up to a computer. This saves time and ensures that all of the students will get to see the same specimen. People can save images viewed through digital microscopes to computers, allowing them to access the image later. This is perfect for a school setting as it lets students recall the image if they need to later describe it or write about its details. Scientific researchers benefit greatly from digital microscopes. They are able to save and print images from the microscope, allowing for close examination. When the images seen through a digital microscope are viewed on a computer screen, it enables several researchers to examine the image at once. There are several different models of digital microscopes. Some have one eyepiece like most conventional microscopes. A handful of models are stereo microscopes , meaning that they have two eyepieces. All digital microscopes have numerous features that make them great tools for education and research.
2021 06 25
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Biomimetic Virus-based Colourimetric Sensors
Biomimetic Virus-based Colourimetric Sensors
Many materials in nature change colours in response to stimuli, making them attractive for use as sensor platform. However, both natural materials and their synthetic analogues lack selectivity towards specific chemicals, and introducing such selectivity remains a challenge. Here we report the self-assembly of genetically engineered viruses (M13 phage) into target-specific, colourimetric biosensors. The sensors are composed of phage-bundle nanostructures and exhibit viewing-angle independent colour, similar to collagen structures in turkey skin. On exposure to various volatile organic chemicals, the structures rapidly swell and undergo distinct colour changes. Furthermore, sensors composed of phage displaying trinitrotoluene (TNT)-binding peptide motifs identified from a phage display selectively distinguish TNT down to 300 p.p.b. over similarly structured chemicals. Our tunable, colourimetric sensors can be useful for the detection of a variety of harmful toxicants and pathogens to protect human health and national security.Our group identified a consensus TNT-binding peptide sequence (WHWQ) using phage display with a commercially available 12mer linear peptide library (Ph.D.-12). To incorporate the TNT-binding peptide, we genetically engineered the M13 phage's major coat proteins (pVIII). The desired peptide sequences were inserted between the first and the sixth amino acids of the amino terminus of wild-type pVIII, replacing residues 2–5 (Ala--Pro to Ala-()-Pro). To incorporate the most stable phage to carry the consensus TNT-binding peptide (WHWQ) identified by phage display, we designed a partial library with sequence of the form ADP using the primer: 5′-ATATATCTGCAGCCCGCAAAAGCG GCCTTTAACTCCC-3′ and the primer 5′-GCTGTCTTTCGCTGC AGAGGGTG-3′ to linearize the vector (=A/C/G/T and =G/T). To incorporate the gene sequences, PCR amplification was performed using Phusion DNA Polymerase, two primers (insertion and linearization) and an M13KE vector with an engineered I site as the template. The obtained product was purified on an agarose gel, eluted by spin column purification, digested with I enzyme and recircularized by an overnight ligation at 16 °C with T4 DNA ligase. The ligated DNA vector was transformed into XL1-Blue electroporation competent bacteria and the amplified plasmid sequence was verified at the University of California, Berkeley, DNA sequencing facility. The pVIII library was screened against TNT and the resulting sequences were tested for stability after large-scale amplification. The library member, ADDWHWQEGDP, was finally chosen to create our TNT–Phage litmus sensors. Alanine-substituted control phage (WAW, AHW and WHA) sequences were synthesized by site-directed mutagenesis of the WHW phage. Using similar genetic engineering approaches, we constructed 4E phage as a control. The constructed phages were amplified using bacterial cultures and purified through standard polyethylene glycol precipitation. The phage solution was further purified by filtration through 0.45 μm pore size membranes. To verify phage stability, DNA sequences were confirmed at each step of the amplification.We created the phage self-assembled colour band patterns using a simple pulling method. The colours of the assembled structures were varied by controlling the pulling speed between 20 and 80 μm min. We constructed a home-built phage deposition apparatus by modifying a syringe pump. We programmed software using C to control the motor speed (between 0.1 μm min and 30 mm min) through an RS232C cable. For preparing Phage litmus matrices, we used 6 mg ml 4E phage suspensions in Tris-buffered saline (12.5 mM Tris and 37.5 mM NaCl, pH 7.5) or 2.4 mg ml WHW-phage suspensions in DI water. A spectrum of coloured bands (each band was obtained at a different pulling speed) was clearly perceptible when the matrices were deposited on gold-coated Si wafers.Fresh turkey head samples were donated from a local turkey farm (Pitman Farms, Sanger, CA, USA). The heads were obtained through overnight delivery immediately after they were slaughtered. The fresh turkey skin samples were immediately taken and processed for optical microscopy and transmission electron microscopy. For histology, 0.5 × 1 cm turkey skin samples were soaked in 20% sucrose in PBS for 2 h, embedded in OCT Compound (Sakura, Torrance, CA, USA), cryosectioned at 5 μm thickness (Shandon Cryostat, Asheville, NC) and stained with Masson's trichrome. Images were collected using an IX71 Microscope (Olympus, Tokyo, Japan). Transmission electron microscopy samples were fixed with 2% glutaraldehyde in 0.1 M sodium cacodylate (pH 7.2) for 1 h, post-fixed with 1% osmium tetroxide in 0.1 M sodium cacodylate (pH 7.2) and rinsed three times with sodium cacodylate (pH 7.2). Dehydration was done using a graded ethanol series (20, 40, 60, 80, 100 and 100%) followed by step-wise infiltration with epon-araldite resin (two parts acetone/one part resin for 1 h, one part acetone/one part resin for 1 h, one part acetone/two parts resin for 1 h, 100% resin for 1 h, 100% resin overnight, 100% resin with benzyl dimethylamine (BDMA) for 1 h) and heat polymerized in a 60 °C oven. Sample blocks were sectioned at 90 nm using a Leica EM UC6 microtome (Leica Microsystems Inc., Buffalo Grove, IL 60089, USA). Grids were stained with 2% uranyl acetate and Reynolds' lead citrate. Imaging was done using a FEI Tecnai 12 transmission electron microscope (FEI, Hillsboro, OR 97124, USA).AFM images were collected using an MFP3D AFM (Asylum Research, Santa Barbara, CA) and analysed using Igor Pro 6.0 (WaveMetrics, Inc., Lake Oswego, OR) and Asylum software package (Asylum Research). All images were taken in tapping mode with a tip spring constant of 2 N m. The probe tips (Ted Pella, Inc., Redding, CA) were made of silicon with a 10-nm radius. The humidity experiments were carried out in a closed liquid cell. We injected a fixed quantity of DI water to control the humidity. FFT analysis of AFM cross-sectional height profiles was used to determine the periodicity of the self-assembled nanofilament structures within the Phage litmus matrices. Numerical computation of the Fourier transform was done with a 2D FFT algorithm in OriginPro 8 (Origin Lab Corp., Northampton, MA) and imageJ v1.44p (National Institutes of Health, USA). We calculated the Fourier power spectra expressed in spatial frequency (μm) from the AFM images.Phage litmus matrices were illuminated by a white light source of a Xenon lamp (X-Cite, Exfo, Mississauga, Canada) and the reflected spectra were obtained using a fibre optic spectrophotometer (USB4000, Ocean Optics, Dunedin, FL) through a Y-shaped bifurcated optical fibre (). An optical fibre fixed on an –– stage was positioned normal to the Phage litmus surface and perpendicular to the scanning direction. Reflectance was measured using a gold-coated Si wafer as a reference. The humidity experiments were performed in a closed glove box (Plas Labs, Inc., Lansing, MI). The humidity was controlled by DI water and monitored using a hygrometer (VWR International Inc., West Chester, PA).To characterize the reflectance spectra of the Phage litmus under omnidirectional illumination, we lit a box coated with aluminium foil with a lamp (Incandescent Light, 150 W, DWC Sylvania, USA; ). We characterized the reflectance spectra while rotating the substrate between 10° and 90° from horizontal. A gold-coated Si wafer was used as a reference.To characterize the swelling behaviour of the Phage litmus, we performed GISAXS experiments before and during exposure to humidity (3 ml of DI water in a closed chamber). The GISAXS data were collected at the beamline 7.3.3 at the Advanced Light Source at Lawrence Berkeley National Laboratory. X-rays with a wavelength of 1.23984 Å (10 keV) were used, and the scattering spectra were collected on an ADSC Quantum 4 μm CCD detector with an active area of 188 × 188 mm (2,304 × 2,304 pixels). The scattering profiles were obtained after a 60-s collection time by integrating the 2D scattering pattern. The sample to detector distance was 1.84791, m and the incidence angle was 0.14°. Line-averaged intensities were reported as versus , where =(4/) × sin(/2), was the wavelength of incident X-rays and was the scattering angle.A home-built sensing and analysis system was developed for real-time chemical sensing. The equipment setup consisted of a gas chamber with an optical opening where a digital microscope (Celestron LLC, Torrance, CA) was attached to monitor the colour of the Phage litmus. The chamber with the Phage litmus inside was positioned on top of a heat block to control the temperature of the chamber. A MATLAB programme (Mathworks Inc., Natick, MA) was run on a PC to control the camera settings, to perform real-time readout and processing of the captured images and to display the real-time RGB data. First, the automatic gain of the digital microscope was turned to manual mode and a fixed gain was retained to prevent unwanted automatic compensation of brightness. The number of regions of interest, usually matching the number of different colour bands on the Phage litmus, was input by keyboard. Next, the specific regions to compare were selected from the first image (reference image) by mouse input. The subsequent images were taken and saved according to a pre-set frame rate (usually every 5 s). The change of the average RGB values with respect to the reference image for each region of interest was calculated and displayed on a graph in real time. We provide typical code from which we performed our experiments in . The vapour-phase experiments were performed by injection of a volume of solvent needed to achieve 300 p.p.m. concentration into a small container inside the chamber through an inlet tube. For explosive exposure experiments, we put excess amounts of each explosive crystal (200 mg) in a sealed chamber (20 ml) and controlled the vapour pressures by temperature. We obtained the concentration of all compounds based on the vapour pressure at each temperature with the assumption of vapour ideality. The vapour pressure of TNT, DNT and MNT was obtained from previously reported values. To collect the data at saturated conditions, we held the Phage litmus in the sealed chamber for 30 min and then obtained corresponding sensing results. To test the specificity of our TNT–Phage litmus sensor towards interfering molecules, experiments were performed in mixed vapours of MNT, DNT and TNT. First, we put the small sealed chambers (1 ml) containing excess amounts of each explosive crystal (200 mg) in a large chamber with the phage litmus. Next, we exposed the chambers to MNT, DNT and TNT vapours sequentially using needles to open each small chamber (). A similar setup was used to perform the same experiments in a background of ethanol vapour (). We performed the control experiments using a 4E–Phage litmus sensor ().Surface plasmon resonance analyses were performed using the Kretschmann optical configuration. A tungsten halogen lamp with a multiwavelength light source was used and a polarizer was positioned on the input path of the light for transverse magnetic fields. The prism coupler and the Phage litmus were mounted on an stage. We made an enclosed cell of 100 μl using polydimethylsiloxane (PDMS) moulds. Flow of solution to the cell was implemented using 1 mm internal diameter tube. We injected 1 ml of solution into the cell at a flow rate of 50 μl min. The outflow from the cell was carried through to a reservoir. The reflected spectrum was measured by a fibre optic spectrometer (USB4000-ultraviolet visible, Ocean Optics) and data acquisition was performed using a homemade LabVIEW programme (LabVIEW 2009, National Instrument, Austin, TX). The surface plasmon resonance spectrum was calculated from linearly polarized light parallel/perpendicular to the incidence plane (TM/TE configuration).iColour analyser is an iOS 5 application software built using the Xcode programming language (Xcode 4.2, Apple Inc., Cupertino, CA) and designed for the iPhone (Apple Inc, compatible with the iPod and iPad). This software has been built to analyse colourimetric changes of the RGB components from a Phage litmus in a systematic manner using a handheld device (). As demonstrated in this paper, the RGB colour components and their changes from the Phage litmus can be linked to specific responses from target molecules. The iColour analyser workflow is constituted of different parts (), as follows:: A channel type (picker) is displayed to choose an analysis mode: single or double channel. Single-channel mode samples from one to five colour matrices of a Phage litmus labelled as S1–S5. The results display one to five different colour matrix RGB components in a bar graph and their values on an 8-bit level. Double-channel mode allows for colour comparison analysis between a reference Phage litmus (before exposure to chemical) and the sample Phage litmus (after exposure to chemical) through comparison between one and five matrices. The RGB values displayed will be the difference between the RGB values of the sample and the reference.: Once the user clicks on the single button of this application, the iPhone takes a picture of the Phage litmus. One can resize and crop the picture of the Phage litmus sample to precisely obtain the target area to analyse.: Once the picture is taken, its central area is cropped and displayed. The picture is converted into a matrix containing the RGB and intensity values of each pixel. The vector data from the iPhone digital camera CCD (Omnivision OV5650, Santa Clara, CA) is processed to get the average of the RGB values from 2,592 × 1,944 pixels over the different areas selected by the user. An analysis table displays the RGB component intensity values and their s.d. An analysis graph will display the RGB values obtained from the sample. The 'average' picture displays a synthesized picture made from either the average RGB values in the case of the single analysis mode, or the difference between the average RGB values of the Phage litmus and its reference in the case of the double comparison mode. After displaying the analysis data and the date and time, a screenshot of the interface is saved in the picture browser of the iPhone and can be transferred easily to any computer through e-mail. In this work, for display purposes, the colour ranges of images are expanded from 5- to 8 bits per colour (RGB colour ranges of 0–31 expanded to 0–255).
2021 06 25
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Formation of Printable Granular and Colloidal Chains Through Capillary Effects and Dielectrophoresis
Formation of Printable Granular and Colloidal Chains Through Capillary Effects and Dielectrophoresis
One-dimensional conductive particle assembly holds promise for a variety of practical applications, in particular for a new generation of electronic devices. However, synthesis of such chains with programmable shapes outside a liquid environment has proven difficult. Here we report a route to simply 'pull' flexible granular and colloidal chains out of a dispersion by combining field-directed assembly and capillary effects. These chains are automatically stabilized by liquid bridges formed between adjacent particles, without the need for continuous energy input or special particle functionalization. They can further be deposited onto any surface and form desired conductive patterns, potentially applicable to the manufacturing of simple electronic circuits. Various aspects of our route, including the role of particle size and the voltages needed, are studied in detail. Looking towards practical applications, we also present the possibility of two-dimensional writing, rapid solidification of chains and methods to scale up chain production.The experimental set-up consisted of a signal generator (SDG1025 Siglent), a high-voltage bipolar amplifier (10HVA24-BP1 HVP), –– motorized translation stage (MTS25-Z8 Thorlabs), a digital microscope (AM7115 Dino-Lite) and a PC for collecting images. The signal electrode for pulling out the particles from a dispersion was made of a thin aluminium wire attached to another motorized translation stage for controlling the pulling rate.Silicone oils (Dow Corning 200 with kinematic viscosity 100 cSt; electric conductivity
2021 06 25
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Woman Shares Gruesome Pics Showing What Years of Gel Manicures Have Done to Her Nails  and It'll Pro
Woman Shares Gruesome Pics Showing What Years of Gel Manicures Have Done to Her Nails and It'll Pro
NO matter how lovely they look, we all know that gel manicures can wreak havoc on our nail beds.Let's be honest though, even that doesn't stop us booking in for our monthly salon appointments... but now one beauty YouTuber has shared the terrifying effects shellac has had on her nails.Australian gel manicure addict Tina Yong filmed the shocking video as part of her "Tinascope" series.Having previously filmed videos where she examines her skin, eyes, and eyelashes under a microscope, Tina has now shed light on the damaging consequences "5 years" of gel manicures can have on the nail beds.From ordinary fluff and dirt to where the nails are slowly peeling away, Tina explained to her 2.4 million subscribers how her nails always "look scratched and thin" after removing her gel.But this was more than just a case of battered nails...Using a digital microscope to film the disgusting video, Tina identified where her "nails have been lifted and peeled off because of the gel polish"."She then likened the huge build-up of dead skin under her nail to "lots of icebergs" around her cuticles.Unsurprisingly, there was also plenty of dirt and "little hairs" hiding under Tina's fragile nails to the point where she had to acknowledge "oh my god, that's so bad!"But there wasn't just a horrifying build-up of dead skin around Tina's battered nails, the beauty vlogger also noticed that her love of gel manicures have also altered the colour of her nails.Estimating to have worn gel nails religiously for the past five to six years, Tina noticed that her nails had now turned a distinct shade of light yellow after previously "always being off white."Tina's up close and personal video has already been viewed over 200,000 times and one horrified follower has said she will "never put my fingers in my mouth again".One intrigued viewer added that she "can't stop watching" even though the video is "SO GROSS."Warning her followers of the dangers of gel manicures, the online beauty guru said: "Usually, if you use normal polish, your nails won't look this when you remove it. They will still look smooth."And if that hasn't convinced us to swap our shellac habit for ordinary polish, we don't know what will.In even more beauty news, this YouTuber uses Poundland beauty products for 24 hours only... and the foundation is a total disaster.Plus this beauty YouTuber shares the surprising kitchen ingredient she uses to shave her bikini line... and you'll definitely have it in your kitchen cupboards.Washing your hair with CHAMPAGNE is the most bonkers beauty braze on Instagram right now... but is it just throwing money down the drain?
2021 06 25
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Discovery of a Female Cat with Testicles Among Weirdest Pet Claims
Discovery of a Female Cat with Testicles Among Weirdest Pet Claims
A North Shore pet owner got the shock of her life to learn her female cat also had testicles. Along with the discovery of a hermaphrodite cat, other owners have been left perplexed after discovering their pets had consumed anything from a roll of dental floss, compact mirror, blanket, sewing needle to a chicken skewer. These discoveries were among the weirdest PetCare claims received by Southern Cross last year. Lisa Newlands adopted her domestic long haired cat Cameo in 2014 with the reassurance she had been spayed. But at the end of last year, Newlands became suspicious about whether it the standard neutering had worked when her usually feisty cat started befriending a stray male. After Cameo became really sick with a high temperature and stopped eating for the second time in two months, an ultrasound revealed she had a large mass in her stomach area. The ginger cat underwent surgery and for the first time in her vet's 13 year career, she discovered two cancerous testicles in the female feline. Cancerous testicles emit oestrogen, which was why the tom cat was hanging around. "The vet was just bamboozled. She had never seen anything like this in her entire career," Newlands said. Cameo's total vet bill was $2531, but Newlands said fortunately $2013 was covered by pet insurance. Newlands estimated Cameo had racked up almost $10,000 in vet bills since she had owned her because she was notorious for getting in fights with other cats and was grateful most of it had been covered by her pet insurance. Another pet owner also claimed on a hefty $8000 vet bill after their german shepherd cut its leg on a metal shoe rack as it tried to escape from two cats. The traumatic incident resulted in the dog having to undergo two surgeries and receive post operative care. In another case, a labrador retriever went under the knife to remove pieces of a blanket it had eaten from its stomach at a cost of $6000. Another owner commented that they were amazed that the chicken skewer eaten by their miniature poodle came out whole after being endoscopically removed. And a hungry beagle's desire to snaffle up a tasty fruit cake also backfired on it after the raisins caused it to have renal failure. The wee beagle had it's kidneys flushed at the vet. But the list of weird claims gets crazier after a french bulldog ate a whole roll dental floss it had found in a visitor's bag and a Shetland sheepdog had to be treated for munching on dish cloths on two separate occasions. The mischievous mutt managed to escape surgery and was given drugs to help it either poo or vomit the rags out. And it wasn't just playful pooches causing their owners angst, a domestic long haired cat also required surgery to remove a sewing needle it had swallowed and devon rex cat had 46 hair ties surgically removed from its stomach. Both treatments cost their owners more than $2000 each. Southern Cross Pet Insurance general manager Anthony McPhail said everyday, unexpected accidents could end up costing pet owners a lot of money at the veterinary clinic. McPhail said while most of the claims processed were for typical illnesses and routine checks, the ones where pets had managed to eat something they shouldn't have still surprised them. He said the stories could be amusing, but still caused quite a lot of stress to the pet and both its owner and their wallet. "We recommend owners prepare for those unexpected veterinary visits by either setting some money aside or considering pet insurance," McPhail said.
2021 07 27
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Citing Privacy Concerns, U.S. Panel Urges End to Secret DNA Testing
Citing Privacy Concerns, U.S. Panel Urges End to Secret DNA Testing
NEW YORK (Reuters) - They're called discreet DNA samples, and the Elk Grove, California, genetic-testing company easyDNA says it can handle many kinds, from toothpicks to tampons. Blood stains from bandages and tampons? Ship them in a paper envelope for paternity, ancestry or health testing. EasyDNA also welcomes cigarette butts (two to four), dental floss ("do not touch the floss with your fingers"), razor clippings, gum, toothpicks, licked stamps and used tissues if the more standard cheek swab or tube of saliva isn't obtainable. If the availability of such services seems like an invitation to mischief or worse - imagine a discarded tissue from a prospective employee being tested to determine whether she's at risk for an expensive disease, for instance - the Presidential Commission for the Study of Bioethical Issues agrees. On Thursday it released a report on privacy concerns triggered by the advent of whole genome sequencing, determining someone's complete DNA make-up. Although sequencing "holds enormous promise for human health and medicine," commission chairwoman Amy Gutmann told reporters on Wednesday, there is a "potential for misuse of this very personal data." "In many states someone can pick up your discarded coffee cup and send it for (DNA) testing," said Gutmann, who is the president of the University of Pennsylvania. "It's not a fantasy to think about how, without baseline privacy protection, people could use this in a way that would be really detrimental," such as by denying someone with a gene that raises their risk of Alzheimer's disease long-term care insurance, or to jack up life insurance premiums for someone with an elevated genetic risk of a deadly cancer that strikes people in middle age. "Those who are willing to share some of the most intimate information about themselves for the sake of medical progress should be assured appropriate confidentiality, for example, about any discovered genetic variations that link to increased likelihood of certain diseases, such as Alzheimer's, diabetes, heart disease and schizophrenia," Gutmann said. The commission took on the issue because whole genome sequencing is poised to become part of mainstream medical care, especially by personalizing medical treatments based on a patient's DNA. That has been driven in large part by dramatic cost reductions, from $2.5 billion per genome in the Human Genome Project of the 1990s and early 2000s to $1,000 soon. Several companies, including Illumina Inc. and Life Technology's Ion Torrent division, sell machines that can sequence a genome for a few hundred dollars, but that does not include the analysis to figure out what the string of 3 billion DNA "letters" means. A three-year-old federal law prohibits discrimination in employment or health insurance based on someone's genetic information but does not address other potential misuses of the data. Without such privacy protection, said Gutmann, people may be reluctant to participate in genetic studies that do whole genome sequencing, for fear their genetic data will not be secure and could be used against them. Recommendations from such panels are not binding but have been used as the basis for policy and legislation. One scenario the panel offers is a "contentious spouse" secretly having a DNA sample sequenced and using it in a custody battle "as evidence of unfitness to parent," perhaps because the DNA showed a genetic risk for mental illness or alcoholism. There are no federal laws against that. Or, the panel said, DNA information might be posted in a social networking site "by a malicious stranger or acquaintance," possibly hurting someone's "chance of finding a spouse, achieving standing in a community, or pursuing a desired career path." The bioethics panel recommends a dozen forms of privacy protection, including that "surreptitious commercial testing" be banned: No gene sequencing or other genetic testing should be permitted without consent from the person the DNA came from, it said. About 25 states currently allow such DNA testing. Critics of the lack of genetic privacy thought greater urgency was needed. "The report lays out a lot of important best practices and does endorse further state and federal regulations, but it doesn't offer a timeline," said Jeremy Gruber, president of the Council for Responsible Genetics, a private group that monitors genetic issues. "What will inevitably happen is whole genome sequencing will enter greater use and we won't have proper regulations to insure privacy." A bill introduced in California, home to many DNA testing companies, by state Senator Alex Padilla would ban surreptitious testing, requiring written authorization from the person the genetic sample was taken from. It is not clear how many labs are willing to analyze DNA without that authorization. In practice, well-known genetic testing companies such as privately held 23andMe test only saliva samples that are too large to acquire surreptitiously, such as from a drinking glass or licked stamp. "A person would really know that they are spitting into a tube," said 23andMe spokeswoman Jane Rubinstein. The full report from the presidential commission is at www.bioethics.gov.
2021 07 28
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