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Open-Source Hardware Is a Low-Cost Alternative for Scientific Instrumentation and Research

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Modern Instrumentation 2012年第2期1卷 8-20页

作者： Daniel K. fisher Peter j. Gould US Forest Service Pacific Northwest Research Station Olympia USA USDA Agricultural Research Service Stoneville USA

Scientific research requires the collection of data in order to study, monitor, analyze, describe, or understand a particular process or event. Data collection efforts are often a compromise: manual measurements can be time-consuming and labor-intensive, resulting in data being collected at a low frequency, while automating the data-collection process can reduce labor requirements and increase the frequency of measurements, but at the cost of added expense of electronic data-collecting instrumentation. Rapid advances in electronic technologies have resulted in a variety of new and inexpensive sensing, monitoring, and control capabilities which offer opportunities for implementation in agricultural and natural-resource research applications. An Open Source Hardware project called Arduino consists of a programmable microcontroller development platform, expansion capability through add-on boards, and a programming development environment for creating custom microcontroller software. All circuit-board and electronic component specifications, as well as the programming software, are open-source and freely available for anyone to use or modify. Inexpensive sensors and the Arduino development platform were used to develop several inexpensive, automated sensing and datalogging systems for use in agricultural and natural-resources related research projects. Systems were developed and implemented to monitor soil-moisture status of field crops for irrigation scheduling and crop-water use studies, to measure daily evaporation-pan water levels for quantifying evaporative demand, and to monitor environmental parameters under forested conditions. These studies demonstrate the usefulness of automated measurements, and offer guidance for other researchers in developing inexpensive sensing and monitoring systems to further their research.

关键词： Open-Source Hardware Arduino Microcontrollers Sensors Datalogger

Exploring the associations between skeletal muscle echogenicity and physical function in aging adults:A systematic review with meta-analyses

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journal of Sport and Health Science 2024年第6期13卷 820-840页

作者： Dustin j.Oranchuk Stephan G.Bodkin Katie L.Boncella Michael O.Harris-Love Muscle Morphology Mechanicsand Performance LaboratoryDepartment of Physical Medicine and RehabilitationUniversity of Colorado Anschutz Medical CampusAuroraCO 80045USA Department of Physical Therapy

Background:Assessment and quantification of skeletal muscle within the aging population is vital for diagnosis,treatment,and injury/disease *** clinical availability of assessing muscle quality through diagnostic ultrasound presents an opportunity to be utilized as a screening tool for function-limiting ***,relationships between muscle echogenicity and clinical functional assessments require authoritative ***,we aimed to(a) synthesize the literature to assess the relationships between skeletal muscle echogenicity and physical function in older adults(≥60 years),(b) perform pooled analyses of relationships between skeletal muscle echogenicity and physical function,and(c) perform sub-analyses to determine between-muscle ***:CINAHL,Embase,MEDLINE,PubMed,and Web of Science databases were systematically searched to identify articles relating skeletal muscle echogenicity to physical function in older ***-of-bias assessments were conducted along with funnel plot ***-analyses with and without sub-analyses for individual muscles were performed utilizing fisher's Z transformation for the most common measures of physical ***'s Z was back-transformed to Pearson's r for ***:Fifty-one articles(n=5095,female=~2759,male=~2301,72.5± 5.8 years,mean±SD(1 study did not provide sex descriptors))were extracted for review,with previously unpublished data obtained from the authors of 13 *** rectus femoris(n=34) and isometric knee extension strength(n=22) were the most accessed muscle and physical qualities,*** relationship between quadriceps echogenicity and knee extensor strength was moderate(n=2924,r=-0.36(95% confidence interval:-0.38 to-0.32),p <0.001),with all other meta-analyses(grip strength,walking speed,sit-to-stand,timed up-and-go) resulting in slightly weaker correlations(r:-0.34 to-0.23,all p <0.001).Sub-analyses determined minimal differences in predicti

关键词： Correlations Echo intensity Elderly Intramuscular fat Strength

Crystal structure of PqqB from <i>Pseudomonas putida</i>at 2.2 Åresolution

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journal of Biophysical Chemistry 2012年第2期3卷 206-210页

作者： Moritz Metlitzky Sandra Puehringer Stuart j. fisher Department of Molecular Biology University of Salzburg Salzburg Austria

Pyrroloquinoline quinone (PQQ) is an important redox-active cofactor for many bacterial dehy-drogenases. It's biosynthetic pathway involves six or seven genes, one of which is pqqB. Former studies indicated that the protein encoded by pqqB, namely PqqB, functions as a PQQ transporter. Here we report the crystal structure of PqqB from Pseudomonas putida at 2.2 ? resolution together with functional studies to verify this theory.

关键词： PqqB PQQ Biosynthetic Pathway X-Ray Crystallography

Discovery of Thioether-bridged Cyclic Pentapeptides Binding to Grb2-SH2 Domain with High affinity

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Discovery of Thioether-bridged Cyclic Pentapeptides Binding ...

Induced Abortion, Mortality, and the Conduct of Science

中国化学会第26届学术年会化学生物分会场

作者： Robert j. fisher Peter P. Roller Laboratory of Protein Chemistry SAIC-Frederick Frederick MD 21702 USA Laboratory of Medicinal Chemistry NCI NIH Frederick MD 21702 USA

Growth factor receptor-bound protein 2 （Grb2） is an essential intracellular adapter protein, consisting of one SH2 domain flanked by two SH3 domains. Grb2-SH2 domain mediates the activation of mitogenic Ras activation pathway through binding to a range of tyrosine-phosphorylated motifs on growth factor receptors such as the epidermal growth factor receptor （EGFR） and erbB2. An aberrant Grb2-depedent Ras activation pathway has been shown to be essential for cellular transformation in a subset of human tumors. Overexpression of Grb2 protein is also related to liver tumorigenesis in mice and human breast cancer cells. Therefore, molecules that can selectively inhibit the linkage of Grb2-SH2 domain to phosphorylated receptors are expected to be useful for the treatment and/or prevention of hyperproliferative diseases such as leukemias, breast and overian cancers. Based upon global modifications, a highly potent peptide ligand 8 was discovered with a Kd=0.36 μM, evaluated by Biacore binding assay.

关键词： Grb2-SH2 domain cyclic peptides G1TE analogs Phosphotyrosine Grb2-SH2 antagonist

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Open journal of Preventive Medicine 2016年第6期6卷 170-177页

作者： james Studnicki Sharon j. MacKinnon john W. fisher Department of Public Health Sciences University of North Carolina at Charlotte Charlotte USA Doctoral Program in Health Services Research University of North Carolina at Charlotte Charlotte USA

There is no credible scientific opposition to the fact that a genetically distinct human life begins at conception and that an induced abortion is a death. Yet, abortion is not reported as a cause of death in the U.S. vital statistics system. Mortality patterns have profound implications for public policy. As a cause of death, we found abortion to be highly consequential, with large racial and ethnic disparities. Abortion represented 16.4% of non-Hispanic White deaths, but 61.1% and 64.0% of non-Hispanic Black and Hispanic deaths respectively. For Years of Potential Life Lost (YPLL), the ubiquitous measure of premature death, abortion accumulated 63.1% of non-Hispanic White YPLL and 86.5% and 87.4% of non-Hispanic Black and Hispanic YPLL respectively. Further, as measured by the availability of valid data and resources allocated for research, there is evidence that the science community is not appropriately engaged on this crucial public health problem.

关键词： Induced Abortion Mortality Demography

Exploring Trends in Microcrack Properties of Sedimentary Rocks: An Audit of Dry and Water Saturated Sandstone Core Velocity–Stress Measurements

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International journal of Geosciences 2012年第4期3卷 822-833页

作者： Doug A. Angus Quentin j. fisher james P. Verdon University of Bristol University of Leeds

Stress dependent rock physics models are being used more routinely to link mechanical deformation and stress perturbations to changes in seismic velocities and seismic anisotropy. In this paper, we invert for the effective non-linear microstructural parameters of 69 dry and saturated sandstone core samples. We evaluate the results in terms of the model input parameters of two non-linear rock physics models: A discrete and an analytic microstructural stress-dependent formulation. The results for the analytic model suggest that the global trend of the initial crack density is lower and initial aspect ratio is larger for the saturated samples compared to the corresponding dry samples. The initial aspect ratios for both the dry and saturated samples are tightly clustered between 0.0002 and 0.001, whereas the initial crack densities show more scatter. The results for the discrete model show higher crack densities for the saturated samples when compared to the corresponding dry samples. With increasing confining stress the crack densities decreases to almost identical values for both the dry and saturated samples. A key result of this paper is that there appears to be a stress dependence of the compliance ratio BN/BT within many of the samples, possibly related to changing microcrack geometry with increasing confining stress. Furthermore, although the compliance ratio BN/BT for dry samples shows a diffuse distribution between 0.4 and 2.0, for saturated samples the distribution is very tightly clustered around 0.5. As confining stresses increase the compliance ratio distributions for the dry and saturated samples become more diffuse but still noticeably different. This result is significant because it reaffirms previous observations that the compliance ratio can be used as an indicator of fluid content within cracks and fractures. From a practical perspective, an overarching purpose of this paper is to investigate the range of input parameters of the microstructural models

关键词： Compliance Ratio Microcrack Properties Saturated Stress Dependent Velocities Ultrasonic

Racial disparity in years of potential life lost to induced abortions

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Open journal of Preventive Medicine 2014年第1期4卷 8-12页

作者： james Studnicki Sharon j. MacKinnon john W. fisher Department of Public Health Sciences University of North Caro-lina at Charlotte Charlotte USA Doctoral Program in Health Services Research University of North Carolina at Charlotte Charlotte USA

The magnitude of the overall prevalence and racial disparity in induced abortion suggests that it is a major influence on the demographic and socioeconomic composition of the population of the United States (US). However, the years of potential lives averted by induced abortion have not been systematically studied. We applied race-specific intra-uterine death estimates to the induced abortions occurring to non-Hispanic (NH) white and non-Hispanic (NH) black women in the US state of North Carolina in 2008. The resultant estimate of births averted by induced abortion was used to project years of potential life lost. All-cause detailed mortality data were used to compare induced abortion with other contributing causes of years of potential life lost before age 75 (YPLL 75). For NH whites, induced abortions in 2008 contributed 59% of total YPLL 75, and 1.5 times the total YPLL 75 from all other causes combined. For NH blacks, induced abortions in 2008 contributed 76% of total YPLL 75 and 3.2 times the total YPLL 75 from all other causes combined. Induced abortion is the overwhelmingly predominant contributing cause of preventable potential lives lost in the North Carolina population, and NH blacks are disproportionately affected.

关键词： Abortion Years of Potential Life Lost

高交联聚乙烯与钴铬合金和陶瓷股骨头匹配使用的磨损和蠕变

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中华骨科杂志 2011年第4期31卷 408-412页

作者： Galvin AL jennings LM Tipper jL Ingham E fisher j 英国利兹大学生物医学工程学院

髋关节骨关节炎患者进行金属对超高分子量聚乙烯（ul tra-high molecular weight polyethylene,UHMWPE）的全髋关节置换是二十世纪最为成功的外科手术之一.据文献报道使用UHMWPE衬垫的骨水泥假体20年成功率达到75%以上[1].

关键词：超高分子量聚乙烯匹配使用钴铬合金股骨头蠕变磨损陶瓷交联

Cardiac tamponade due to group a streptococcal pericarditis in a 10-month-old boy and a review of the literature

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Open journal of Pediatrics 2011年第4期1卷 87-89页

作者： Matthew C. Schwartz Matthew j. Gillespie Paul Stephens Brian fisher 不详

Group A streptococcus (GAS) is a rare cause of purulent pericarditis in pediatric patients as only 7 cases have been reported. We present a 10-month-old boy who developed cardiac tamponade from GAS and was successfull... 详细信息

关键词： Streptococcus Pericarditis Pericardiocentesis Tamponade