A 9-Bit Flash Analog to Digital Convertor

Need constantly exists for converters with higher resolution, faster conversion speed and lower power dissipation. High-speed analog to digital converters (ADC’s) have been based on flash architecture, because all comparators sample the analog input voltage simultaneously, this ADC is thus inherently fast. Unfortunately, flash ADC requires 2N - 1 comparators to convert N bit digital code from an analog sample. This makes flash ADC’s unsuitable for high-resolution applications. This paper demonstrates a simple technique to reduce comparator requirement of 9-bit flash ADC that requires as few as 256 comparators for 9-bit conversion. In this approach, the analog input range is partitioned into 256 quantization cells, separated by 255 boundary points. A 8-bit binary code 00000000 to 11111111 is assigned to each cell. A 9-bit flash converter requires 512 comparators, while proposed technique reduces number of comparator requirements to 256 for 9-bit conversion

Impact of COVID-19 on cardiovascular testing in the United States versus the rest of the world

Objectives: This study sought to quantify and compare the decline in volumes of cardiovascular procedures between the United States and non-US institutions during the early phase of the coronavirus disease-2019 (COVID-19) pandemic. Background: The COVID-19 pandemic has disrupted the care of many non-COVID-19 illnesses. Reductions in diagnostic cardiovascular testing around the world have led to concerns over the implications of reduced testing for cardiovascular disease (CVD) morbidity and mortality. Methods: Data were submitted to the INCAPS-COVID (International Atomic Energy Agency Non-Invasive Cardiology Protocols Study of COVID-19), a multinational registry comprising 909 institutions in 108 countries (including 155 facilities in 40 U.S. states), assessing the impact of the COVID-19 pandemic on volumes of diagnostic cardiovascular procedures. Data were obtained for April 2020 and compared with volumes of baseline procedures from March 2019. We compared laboratory characteristics, practices, and procedure volumes between U.S. and non-U.S. facilities and between U.S. geographic regions and identified factors associated with volume reduction in the United States. Results: Reductions in the volumes of procedures in the United States were similar to those in non-U.S. facilities (68% vs. 63%, respectively; p = 0.237), although U.S. facilities reported greater reductions in invasive coronary angiography (69% vs. 53%, respectively; p < 0.001). Significantly more U.S. facilities reported increased use of telehealth and patient screening measures than non-U.S. facilities, such as temperature checks, symptom screenings, and COVID-19 testing. Reductions in volumes of procedures differed between U.S. regions, with larger declines observed in the Northeast (76%) and Midwest (74%) than in the South (62%) and West (44%). Prevalence of COVID-19, staff redeployments, outpatient centers, and urban centers were associated with greater reductions in volume in U.S. facilities in a multivariable analysis. Conclusions: We observed marked reductions in U.S. cardiovascular testing in the early phase of the pandemic and significant variability between U.S. regions. The association between reductions of volumes and COVID-19 prevalence in the United States highlighted the need for proactive efforts to maintain access to cardiovascular testing in areas most affected by outbreaks of COVID-19 infection

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Not AvailableNanotechnology has opened up new vistas for applications in almost all the disciplines of veterinary and animal sciences. Zinc oxide (ZnO) has been used as an alternative to antibiotics in animal feed. It has also been widely used for wound healing and various skin disorders. Recently ZnO nanoparticles (NPs) have attracted attention owing to their unique features. There can be numerous applications of ZnO NPs due to their antibacterial, antineoplastic, wound healing, ultraviolet scattering and angiogenic properties. These have also been used to promote tissue repair, as a food preservative and as feed additive. This paper reviews the recent developments in ZnO NPs research and its potential for application in animal health and production.Not Availabl

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Not AvailableNanotechnology has opened up new vistas for applications in almost all the disciplines of veterinary and animal sciences. Zinc oxide (ZnO) has been used as an alternative to antibiotics in animal feed. It has also been widely used for wound healing and various skin disorders. Recently ZnO nanoparticles (NPs) have attracted attention owing to their unique features. There can be numerous applications of ZnO NPs due to their antibacterial, antineoplastic, wound healing, ultraviolet scattering and angiogenic properties. These have also been used to promote tissue repair, as a food preservative and as feed additive. This paper reviews the recent developments in ZnO NPs research and its potential for application in animal health and production.Not Availabl

Development of sample collection methods and preliminary identifications of aphid salivary proteins

Master of ScienceDepartment of ChemistryChristopher T. CulbertsonThe study of aphid salivary secretome has practical importance on understanding interactions of aphids and their host plants. Around 250 species of aphids out of the identified 4000 aphid species are considered as serious pests. The experiments were performed with pea aphids (Acyrthosiphon pisum) that were feeding on bean plants (Vivia fabe). Pea aphids feed on plant phloem sap by probing their stylet into the sieve elements of the plant and secreting saliva for external digestion. In order to collect aphid salivary proteins from the secreted saliva, small scale and large scale sample collection methods were carried out. The small scale sample method was performed in microfluidic devices using 10-25 aphids. Aphids were able to feed on the artificial diet by probing through a stretched ParafilmTM and survived for 2-3 days in the microfluidic devices. The experiments proved that the aphid survival and feeding rate could be improved with the factors such as ventilation, light intensity and increasing diet volume. However it was difficult to collect sufficient amounts of aphid saliva for detection using small scale devices. The large scale sample collection method was performed by feeding 8000 aphids in large screened chamber for 24/48h. The collected salivary samples after undergone a concentration process was capable of collecting detectable aphid salivary secretions. The experimental conditions were adjusted to obtain optimized HPLC separations. Finally, LC/MS/MS followed by peptide sequence database searching were able to identify potential aphid salivary proteins

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Not AvailableZinc oxide nanoparticles are important nanomaterials currently under research due to their applicability in nanomedicine. Toxicity of ZnO NPs has been extensively studied and has been shown to affect various cell types and animal systems. In this study, we investigated hemolytic potential and oxidative stress inflicted by ZnO NPs and ZnO NPs-loaded-sodium alginate-gum acacia hydrogels on horse erythrocytes and African green monkey kidney (Vero) cells. Our study provides a better understanding of the hemolytic and oxidative effects of interaction of ZnO NPs and ZnO NPs released from polymeric hydrogels with the biological system. Remarkable aggregation of erythrocytes was noted in the higher concentration of ZnO NPs treated erythrocytes as compared to erythrocytes treated with ZnO NPs-loaded hydrogels. ZnO NPs-loaded hydrogels treated Vero cells significantly reduced oxidative stress as evidenced by less malondialdehyde production as compared to that of ZnO NPs treated cells. Normal horse erythrocytes when treated with ZnO NPs in in vitro condition undergo oxidative damage, and contribute in augmenting the toxicity. We demonstrated that polymeric ZnO NPs reduced the undesirable effects provoked by ZnO NPs on mammalian cells.Not Availabl