An inexpensive electronic device for measuring electroantennogram responses to sex pheromone components with a voltmeter

ABSTRACT. An inexpensive, portable device which allows measurement of electroantennogram (EAG) maximum amplitudes with a voltmeter instead of an oscilloscope is described. Potential advantages of the device include more rapid recording, low-cost construction of additional EAG recording systems for a laboratory with several users, and portability allowing studies in the field and occasional bench top use. The device is intended for use in conventional EAG recording, where EAG signals with rapid depolarizations are being measured, and where the maximum amplitude of the EAG signal is the only parameter of interest.     

Fabrication of a microfluidic device for the compartmentalization of neuron soma and axons

In this video, we demonstrate the technique of soft lithography with polydimethyl siloxane (PDMS) which we use to fabricate a microfluidic device for culturing neurons. Previously, a silicon wafer was patterned with the design for the neuron microfluidic device using SU-8 and photolithography to create a master mold, or what we simply refer to as a "master". Next, we pour the silicon polymer PDMS on top of the master which is then cured by heating the PDMS to 80 degrees C for 1 hour. The PDMS forms a negative mold of the device. The PDMS is then carefully cut and lifted away from the master. Holes are punched where the reservoirs will be and the excess PDMS trimmed away from the device. Nitrogen is used to blow away any excess debris from the device. At this point the devices are now ready for use and can either bonded to corning No. 1 cover glass with a plasma sterilizer/cleaner or can be reversibly bound to the cover glass by simply placing the device on top of the cover glass. The reversible bonding of the device to glass is covered in a separate video and requires first that the device be sterilized either with 70% ethanol or by autoclaving. Plasma treating sterilizes the devices so no further treatment is necessary. It is, however, important, when plasma-treating the devices, to add liquid to the devices within 10 minutes of the plasma treatment while the surfaces are still hydrophilic. Waiting longer than 10 minutes to add liquid to the device makes it difficult for the liquid to enter the device. The neuron devices are typically plasma-bound to cover glass and 0.5 mg/ml poly-L-lysine (PLL) in pH 8.5 borate buffer is immediately added to the device. After a minimum of 3 hours incubating with PLL, the devices are washed with dH2O water a minimum of 3 times with at least 15 minutes between each wash. Next, the water is removed and fresh media is added to the device. At this point the device is ready for use. It is important to remember at this point to never remove all the media from the device. Always leave media in the main channel.     

Successful non-invasive management of erectile impotence in diabetic men

The effectiveness of a device designed to overcome erectile impotence was assessed in 10 insulin dependent diabetics with no other cause for their erectile impotence. The 10 men and their partners were instructed how to use the device, which uses suction to induce penile engorgement and maintains erection with a constriction band. After three months they answered a questionnaire about its effectiveness and acceptability, assessing these by visual analogue scales. All the patients achieved lasting erections with the device and gave high mean scores for ease of use, effectiveness, and satisfaction, but three partners refused to complete the questionnaire having failed to come to terms with using the device. One couple stopped using it because of marital disharmony.This device provides a practical alternative for the treatment of erectile impotence in diabetic men. Unlike invasive treatments, it does not necessitate lengthy assessments of autonomic, endocrine, and erectile function and is safe to use and relatively cheap.     

Can a tablet device alter undergraduate science students' study behavior and use of technology?

This article reports findings from a study investigating undergraduate biological sciences students' use of technology and computer devices for learning and the effect of providing students with a tablet device. A controlled study was conducted to collect quantitative and qualitative data on the impact of a tablet device on students' use of devices and technology for learning. Overall, we found that students made extensive use of the tablet device for learning, using it in preference to laptop computers to retrieve information, record lectures, and access learning resources. In line with other studies, we found that undergraduate students only use familiar Web 2.0 technologies and that the tablet device did not alter this behavior for the majority of tools. We conclude that undergraduate science students can make extensive use of a tablet device to enhance their learning opportunities without institutions changing their teaching methods or computer systems, but that institutional intervention may be needed to drive changes in student behavior toward the use of novel Web 2.0 technologies.     

A versatile apparatus for performing anaerobic optical titrations with provision for multiple sampling of the reaction mixture.

An all-glass device sultable for the oxido-reductive titrations of air-sensitive compounds is deseribed. The device has a provision for monltoring the optical spectrum and for sampling the reaction mixture with direct transfers of the sample into electron-paramagnetic resonance sample tubes. The performance of the device is evaluated and an example of its use is given.     

Development of a three-microneedle device for hypodermic drug delivery and clinical application

There is a potential use for intradermic or hypodermic drug delivery in skin surgery or aesthetic surgery. Hypodermic delivery with the use of a noninvasive device can be a more useful, reliable, and effective administration route to obtain higher compliance. The authors developed a microneedle device composed of three fine needles (three-microneedle device). The tip of each needle was fabricated with a bevel angle to release a drug broadly into the tissue in a horizontal fashion. In this study, the authors investigated the usefulness of this newly developed three-microneedle device for hypodermic liquid injection, focusing on the optimum insertion depth and the diffusion of injected materials to the tissue. The authors also assessed the efficacy of and patient satisfaction with three-microneedle device injections of botulinum toxin type A for wrinkle reduction in patients with glabellar rhytides. The three-microneedle device yielded consistent results in hypodermal diffusion. On India ink diffusion test and ultrasonographic imaging, three-microneedle device injection showed a broad diffusion in horizontal extension, as compared with usual 31-gauge needle injection. The efficiency and satisfaction of the patients receiving botulinum toxin type A with the three-microneedle device were highly rated. Three-microneedle device delivery enables accurate and broad diffusion of injected substances, thus reducing the total dose and/or injection number of drugs. CLINICAL QUESTION/LEVEL OF EVIDENCE: Therapeutic, IV.     

Continuous intrauterine copper contraception for 3 years: comparison of replacement at 2 years with continuation of use.

A total of 1245 women had a copper 7 intrauterine contraceptive device (IUD) inserted in 1971-3 were followed up for three years (22 761-5 women months of use). After 24 months 483 women elected to continue with the same copper 7 (continuation group), and 183 had their copper 7 replaced with a new one (replacement group). The subsequent pregnancy and expulsion rates were both significantly lower in the replacement group. The higher pregnancy rate among the women who continued to use their copper 7 device for a third year suggests that although the copper is still there, it is not available for contraceptive action. Replacing the device at 24 months did not seem to cause again the problems that usually occur in the first six months of IUD use.     

A laser-aligned method for anthropometry of hands

We have developed a laser-aligned measuring device to facilitate the measurement of linear hand dimensions. Our objective has been to make a simple, clinically applicable device for anthropometry of the hands in patients with arthritis in order to gauge the progression of hand deformities. The system provides an alternative to the use of rules, tapes, photogrammetry and least-squares devices which have previously been applied to hand measurements. The system delivers results which are not significantly different from those measured with rules and callipers and has a similar level of accuracy. The use of laser pointers for alignment facilitates measurements which necessitate picking the highest point of the hand. The device is portable and simple to use in the clinic. We have used it to measure hand dimensions in normal subjects and patients with arthritis. However, the system could equally well be used to facilitate measurement of other objects with an irregular surface profile.     

The possible use of PKZh-type devices (liquid purity control devices) in the analysis of cell suspensions

PKZh means "device for liquid purity control". A possibility is considered to use the native PKZh type device for carrying out quantitative analyses of cellular suspension components, for routine bacterial suspension, agglutinated bacterial suspension and erythrocyte suspension. The flowing photometric principle of particle recording, used in the device, allows to analyse biological suspensions with small amounts of components. The device provides a differential count of some cells and their conglomerates in six dimensional ranges, within the frames of 1-25 micron or higher. The time consumption for one sample analysis is 10-15 seconds.     

Skin-stretching device for intraoperative primary closure of radial forearm flap donor site

The use of a skin-stretching device to close radial forearm donor-site defects in patients being treated for intraoral cancer is described. Intraoperative application of the device achieved primary closure of the donor site during the time course of the reconstructive procedure with no requirement for additional operative time. The device was used successfully in seven patients with two instances of marginal skin necrosis and delayed healing but good long-term functional and cosmetic outcomes in all cases.     

Non-plasma bonding of PDMS for inexpensive fabrication of microfluidic devices

In this video, we demonstrate how to use the neuron microfluidic device without plasma bonding. In some cases it may be desirable to reversibly bond devices to the Corning No. 1 cover glass. This could be due, perhaps, to a plasma cleaner not being available. In other instances, it may be desirable to remove the device from the glass after the culturing of neurons for certain types of microscopy or for immunostaining, though it is not necessary to remove the device for immunostaining since the neurons can be stained in the device. Some researchers, however, still prefer to remove the device. In this case, reversible bonding of the device to the cover glass makes that possible. There are some disadvantages to non-plasma bonding of the devices in that not as tight of a seal is formed. In some cases axons may grow under the grooves rather than through them. Also, because the glass and PDMS are hydrophobic, liquids do not readily enter the device making it necessary at times to force media and other reagents into the device. Liquids will enter the device via capillary action, but it takes significantly longer as compared to devices that have been plasma bonded. The plasma cleaner creates temporary hydrophilic charges on the glass and device that facilitate the flow of liquids through the device after bonding within seconds. For non-plasma bound devices, liquid flow through the devices takes several minutes. It is also important to note that the devices to be used with non-plasma bonding need to be sterilized first, whereas plasma treated devices do not need to be sterilized prior to use because the plasma cleaner will sterilize them.     

A telemetry-based device to determine the force-displacement behaviour of materials in high impact loading situations

Meaningful testing of stab resistant body armour requires the use of realistic body tissue simulants. A device for the determination of the force-displacement behaviour of materials in high impact loading situations has been developed for the testing of such simulants. Force measurement is achieved with the use of electrical foil strain gauges applied to a cylindrical load cell. A piezo-resistive accelerometer (+/- 500 g) is used to calculate the displacement of the device through double integration of its signal, with the impact velocity used as a boundary condition. The signals from the strain gauge circuit and the accelerometer are sampled at 2500 Hz. The data are transmitted to a receiver via telemetry using a 418 MHz FM transmitter and from the receiver to a laptop PC via the serial port. Calibration of the device is described and sample results showing forces up to 2500 N and displacements up to 0.04 m are presented.     

Surgical removal of duct occluder device under mild hypothermia without cardiopulmonary bypass

Because the use of percutaneous intervention is increasing for the closure of the patent ductus arteriosus, the procedure-related complications are also on rise, with migration of the device being most common. The routine practice is to remove the migrated duct occluder device under cardiopulmonary bypass. Amplatzer duct occluder used in a 4-month-old infant dislodged into the descending thoracic aorta. It was removed by the posterolateral thoracotomy under mild hypothermia through juxtaductal aortotomy between the aortic cross-clamps. The use of cardiopulmonary bypass is thus avoided.     

Effects of straddle-harvester design on cane blight (Leptosphaeria coniothyrium) of red raspberry

A new fruit catching device developed for raspberry straddle harvesters to reduce wounding of young canes and their consequent infection by Leptosphaeria coniothyrium was tested. During picking the young canes were contacted only by the foam rubber on a pair of belts which moved backwards along the harvester at the same speed that the machine advanced. The incidence of canes with cane blight lesions in 1981 was 18% following the use of the new device in 1980, and 79% following the use of a conventional commercial harvester equipped with overlapping metal fruit-catching plates. In comparison with the latter plates, the new device avoided wounding the cane surface directly: when the belt marks on these canes were inoculated with mycelium, however, the disease incidence was 77%. The new device caused wounds in 1980 by ripping leaves from nodes. In comparison with the commercial harvester the new device led to smaller lesions in 1981 and a lower percentage of canes dead above the fruit-catching zone. A modified new catching device tested in 1982 made barely detectable pressure marks on the young canes without bruising them. Only 6·6% of these canes developed vascular lesions after inoculation, an incidence similar to that for unwounded control canes (2·5%). The modified new device is advised for regions prone to cane blight where the cropping system has young and fruiting canes growing together.     

Programmed electrical stimulation and Amiodarone therapy for the control of persistent junctional tachycardia

The use of radiofrequency as a means of synchronization and stimulation does not necessitate an external lead, and thus has allowed the construction of an implantable device for long-term treatment of reentry tachycardias. The device is used along with Amiodarone therapy and can be triggered by the patient himself.     

Testing use of a potential cognitive enrichment device by an Indo-Pacific bottlenose dolphin (Tursiops aduncus)

Cognitive enrichment aims to provide animals with opportunities to use their cognitive skills and to promote behaviors associated with positive wellbeing. Cooperation in mammals has been recorded during various behavioral contexts such as hunting, mating, playing, and parental care. Coordinated activity, often with some level of problem-solving action included, is required during cooperation. To investigate dolphins’ ability for collaborative problem-solving, an enrichment device was introduced to two adult male Indo-Pacific bottlenose dolphins (Tursiops aduncus). The device contained fish and ice and was designed to be opened by simultaneously pulling on both ends. After repeated presentation, it became apparent that only one dolphin had active interest in the device. To facilitate opportunities for problem-solving by this individual, an alternative collaborator, a human partner, was provided. Still, both dolphins had access to the device throughout the entire experiment. After the first opening, the same dolphin was highly successful in collaborating with the human in both joined (93%) and delayed (100%) partner conditions. The device provided a novel opportunity for the dolphin to use his cognitive skills. Even though only one dolphin participated actively, both dolphins showed varying degrees of interest to the device throughout the study. Both dolphins spent an average of 48% and 16% of their time, respectively, with the device, which resulted in a significant decrease in their other two most frequently observed behaviors: swimming and poolside observation. As a novel cognitive challenge, the device may be considered as a type of cognitive enrichment.     

Polymer waveguide sensor for early diagnostic and wellness monitoring

This paper unveils a platform to develop a compact, simple, reusable and disposable, and cost effective hand-held urinalysis device for home-health-care and doctor's office uses. A polymeric optical waveguide and colorimetric absorption were used as an optical sensor and sensing mode, respectively. The results of the tests show that the device was able to deliver quantitative results with the detection limits better than 0.1g/L, 0.2g/L, 0.025 g/L, and 0.1g/L for glucose, creatinine, albumin and total protein, respectively. There are some superiorities of this device as compared to the dip-stick counterpart, that are, better sensitivity, ability to deliver quantitative results and reusability. The device is being further miniaturized to use a LED and photodiode as a light source and detector, respectively. It is believed the device has potential for early diagnostic and wellness monitoring tool.     

Use of the cylinder osteotome for cancellous bone grafting

An instrument is described for removing iliac crest cancellous bone grafts under local anesthesia. The device has widespread applications for plastic and orthopedic surgery. The convenience of obtaining bone grafts with this device broadens the use of bone-grafting techniques in patients in whom the need for bone graft is unexpected.     

Device thrombogenicity emulation: a novel method for optimizing mechanical circulatory support device thromboresistance

Mechanical circulatory support (MCS) devices provide both short and long term hemodynamic support for advanced heart failure patients. Unfortunately these devices remain plagued by thromboembolic complications associated with chronic platelet activation--mandating complex, lifelong anticoagulation therapy. To address the unmet need for enhancing the thromboresistance of these devices to extend their long term use, we developed a universal predictive methodology entitled Device Thrombogenicity Emulation (DTE) that facilitates optimizing the thrombogenic performance of any MCS device--ideally to a level that may obviate the need for mandatory anticoagulation. DTE combines in silico numerical simulations with in vitro measurements by correlating device hemodynamics with platelet activity coagulation markers--before and after iterative design modifications aimed at achieving optimized thrombogenic performance. DTE proof-of-concept is demonstrated by comparing two rotary Left Ventricular Assist Devices (LVADs) (DeBakey vs HeartAssist 5, Micromed Houston, TX), the latter a version of the former following optimization of geometrical features implicated in device thrombogenicity. Cumulative stresses that may drive platelets beyond their activation threshold were calculated along multiple flow trajectories and collapsed into probability density functions (PDFs) representing the device 'thrombogenic footprint', indicating significantly reduced thrombogenicity for the optimized design. Platelet activity measurements performed in the actual pump prototypes operating under clinical conditions in circulation flow loops--before and after the optimization with the DTE methodology, show an order of magnitude lower platelet activity rate for the optimized device. The robust capability of this predictive technology--demonstrated here for attaining safe and cost-effective pre-clinical MCS thrombo-optimization--indicates its potential for reducing device thrombogenicity to a level that may significantly limit the extent of concomitant antithrombotic pharmacotherapy needed for safe clinical device use.     

A Simple and Safe Device for Spreading Ultrathin Sections with Chloroform

A simple and safe device for spreading ultrathin sections for electron microscopy is described. The use of this device minimizes the release of chloroform vapor during section spreading.