cssi/SciSciGPT-SciSciNet huggingface dataset:
Trace Elements and Metals as Anticarcinogens

The inhibition of tumor induction and development by trace elements and metals has only recently become a major area of exploration in the research community. Although thousands of publications report trace element and metal modifications of enzymes and other subcellular components, on only few occasions has the relevance of these observations to the carcinogenic process been evaluated. Interest in these modifying factors has been somewhat blunted because of their sometimes mercurial ability to either augment or inhibit the carcinogenic process. As environmentalists and epidemiologists have associated modifiers with increased and reduced cancer rates and as nutritionists have labeled certain heretofore unrecognized trace elements and metals “nutrients,” the cancer researcher has turned his attention to specific events in the multistage origin of tumors that are potential targets for modification.
Strategies for the Design and Synthesis of Hybrid Multifunctional Nanoporous Materials

This chapter discusses the design and synthesis of multifunctional active sites in ordered nanoporous materials. First, the formation of homogeneous molecular monolayer structures is described. Hybrid nanoporous materials modified with functional molecules and groups are widely investigated for many applications. The molecular chain conformations depend on the surface roughness of the pore channels. A step-wise growth model has been proposed to account for the step-wise pore dimension change. This paper also discusses the use of supercritical fluids as delivery media to improve the effectiveness of surface functionalization. This technique has been used successfully to synthesize size-exclusive microporous acid catalysts. Finally, the formation of architectured monolayer molecular structures is discussed. The use of imprinting or lithograph techniques allows the synthesis of hierarchical porous materials with tunable size-and-shape selective microporosity.
Effect of Losartan and Fish Oil on Plasma IL-6 and Mobility in Older Persons. The ENRGISE Pilot Randomized Clinical Trial.

Background Low-grade chronic inflammation, characterized by elevations in plasma Interleukin-6 (IL-6), is an independent risk factor of impaired mobility in older persons. Angiotensin receptor blockers and omega-3 polyunsaturated fatty acids (ω-3) may reduce IL-6 and may potentially improve physical function. To assess the main effects of the angiotensin receptor blocker losartan and ω-3 as fish oil on IL-6 and 400 m walking speed, we conducted the ENRGISE Pilot multicenter randomized clinical trial. Methods The ENRGISE Pilot enrolled participants between April 2016 and June 2017, who participated for 12 months. Participants were aged ≥70 years with mobility impairment, had IL-6 between 2.5 and 30 pg/mL, and were able to walk 400 m at baseline. Participants were randomized in three strata 2 × 2 factorial to: (i) losartan 50-100 mg/d or placebo (n = 43), (ii) fish oil 1,400-2,800 mg/d or placebo (n = 180), and (iii) with both (n = 66). Results Two hundred eighty-nine participants were randomized (mean age 78.3 years, 47.4% women, 17.0% black). There was no effect of losartan (difference of means = -0.065 ± 0.116 [SE], 95% confidence interval [CI]: -0.293-0.163, p = .58) or fish oil (-0.020 ± 0.077, 95% CI: -0.171-0.132, p = .80) on the log of IL-6. Similarly, there was no effect of losartan (-0.025 ± 0.026, 95% CI: -0.076-0.026, p = .34) or fish oil (0.010 ± 0.017, 95% CI: -0.025-0.044, p = .58) on walking speed (m/s). Conclusions These results do not support the use of these interventions to prevent mobility loss in older adults at risk of disability with low-grade chronic inflammation. Registration Clinicaltrials.gov NCT02676466.
Biosensor-guided improvements in salicylate production by recombinant Escherichia coli

Salicylate can be biosynthesized from the common metabolic intermediate shikimate and has found applications in pharmaceuticals and in the bioplastics industry. While much metabolic engineering work focused on the shikimate pathway has led to the biosynthesis of a variety of aromatic compounds, little is known about how the relative expression levels of pathway components influence salicylate biosynthesis. Furthermore, some host strain gene deletions that improve salicylate production may be impossible to predict. Here, a salicylate-responsive transcription factor was used to optimize the expression levels of shikimate/salicylate pathway genes in recombinant E. coli, and to screen a chromosomal transposon insertion library for improved salicylate production. A high-throughput colony screen was first developed based on a previously designed salicylate-responsive variant of the E. coli AraC regulatory protein (“AraC-SA”). Next, a combinatorial library was constructed comprising a series of ribosome binding site sequences corresponding to a range of predicted protein translation initiation rates, for each of six pathway genes (> 38,000 strain candidates). Screening for improved salicylate production allowed for the rapid identification of optimal gene expression patterns, conferring up to 123% improved production of salicylate in shake-flask culture. Finally, transposon mutagenesis and screening revealed that deletion of rnd (encoding RNase D) from the host chromosome further improved salicylate production by 27%. These results demonstrate the effectiveness of the salicylate sensor-based screening platform to rapidly identify beneficial gene expression patterns and gene knockout targets for improving production. Such customized high-throughput tools complement other cell factory engineering strategies. This approach can be generalized for the production of other shikimate-derived compounds.
Integrating multiple transportation modes into measures of spatial food accessibility

Abstract Introduction People can access to healthy food via different modes of transportation, such as traveling by car, transit, bicycle and foot. We categorize current measures of food accessibility under an origin-destination-mode framework and find that few of them integrate multiple travel modes. As a result, these measures can bias the identification of truly low-access areas. Methods To fill this gap, we propose two new measures that integrate sub-populations of various travel modes, and estimate the overall food accessibility of a whole population. Taking Florida, USA, as a study area, we illustrate our measures with actual multiple mode commuting data from the U.S census transportation planning products (CTPP). We then compare the results to those from conventional single-modal measures. Results The proposed multiple-mode measures tend to estimate a larger population with low accessibility and fewer accessible supermarkets for a census tract, as compared to single-mode measures. The incorporation of multiple travel modes into food accessibility measures also narrows the disparities between urban and rural areas, which are indicated by conventional measures. Conclusions By considering modal-split subpopulations, our measures offer a more realistic representation of local people's travel for grocery shopping, and thus a better identification of populations with low food access. The finer modeling scale at a subpopulation level provides health and urban planners more flexibility in policy design, in that interventions can be tailored to not only a neighborhood but also a specific subpopulation within it. Such knowledge could improve the cost-effectiveness of food intervention programs.
Construction and Verification of the Constitutive Model of Pure Copper Deformation at Elevated Temperatures

The deformation behavior of pure copper was studied in hot compression tests in the temperature range of 773–1173 K and strain rate interval of 0.001–1.0 s–1, the corresponding flow stress curves were plotted. The new method to calculate critical and saturation stresses was devised, quantitative analysis of strain hardening and dynamic softening was presented, a three-stage constitutive model was constructed to predict the flow stress of pure copper. As predicted and measured flow stress comparison indicate, the physical constitutive model can accurately characterize hot deformation of pure copper. With dynamic recovery and/or recrystallization. Numerical simulation of an upsetting process is carried out by implementing the constitutive model into commercial software. This model can be put to practical use and be quite promising for improving efficiency of a hot forging process for pure copper components.
Spinal Anesthesia for Transurethral Resection of a Bladder Tumor in a 101-year-old Man

This patient, the oldest spinal anesthesia case the authors have ever had, is presented because of its interest as regards the age of the patient, the technique of spinal anesthesia, the dose of local anesthetic, and the length of surgery time. The outcome was uneventful during the immediate and late postoperative period.
BRAFV600E, hypothyroidism, and human relaxin in thyroid carcinogenesis.

BRAFV600E, a major driver of thyroid cancer, evaluated in the context of thyroid hormones and human relaxin. Immunohistochemical expressions of BRAFV600E, TSH, TSH receptor (TSHR), T4, T3 receptor (T3R), RLNH2, and its receptor, RXFP1, were evaluated in thyroid tumors from a retrospective U.S. population of 481 cancer cases diagnosed in 1983–2004. BRAFV600E was expressed in 52% of all thyroid tumors; expression of other markers ranged from 25% for T4 to 98% for RLNH2. Tumors predominantly exhibited hypothyroid-like conditions characterized by elevated TSH and TSHR and reduced T4. BRAFV600E prevalence was significantly higher in tumors expressing TSH, TSHR, T3R, and RXFP1 and lower in tumors expressing T4. The proportion of BRAFV600E mutation in classic papillary tumors significantly increased from 56 to 72% over the 21-year period of diagnoses, while expression of RXFP1, TSH, TSHR, and T3R decreased in non-tumor. Racial/ethnic differences were observed in thyroid hormone marker expression. Non-tumor expression of TSH, TSHR, and T3R were each associated with shorter overall survival, but did not remain significant after adjustment for demographic and clinical factors. Our study provides the first evidence of the potential interaction of BRAFV600E mutation, relaxin, and thyroid hormones in thyroid carcinogenesis. Moreover, our results suggest that hypothyroidism, influenced by RLNH2 activity, may underlie the development of the majority of thyroid cancers and mediate the role of BRAFV600E in thyroid carcinogenesis. BRAFV600E mutation is increasing in papillary thyroid cancers and may be contributing to the rising incidence of this malignancy.
SIRT6 Regulates Telomere Movement in the Presence and Absence of Oxidative Damage

Oxidative damage to telomeres leads to telomere attrition and genomic instability and is likely a major cause of incomplete ends of replicated chromosomes. While the maintenance of telomere integrity requires restriction of telomere movement within the nucleus, increased telomere movement facilitates the repair of DNA damage at telomeres. Whether oxidative damage induces telomere movement and how telomere mobility is regulated remains poorly understood. Here, we show that oxidative damage triggers directional telomere movement, and that the human Sir2 homolog, Sirtuin 6 (SIRT6), is required for this process. This function of SIRT6 is mediated by the chromatin-remodeling protein SNF2H, which promotes chromatin decondensation in response to DNA damage. Interestingly, in undamaged cells, SIRT6 restricts telomere movement by stabilizing the shelterin protein TRF2 at telomeres. Together, our results suggest that SIRT6 plays two distinct roles in telomere movement in the presence and absence of oxidative damage through chromatin remodeling and sheltering stabilization, shedding new light onto the functions of SIRT6 in telomere structural maintenance.
Using Participatory Design to Engage Physicians in the Development of a Provider-Level Performance Dashboard and Feedback System

Abstract Problem Definition Performance feedback, in which clinicians are given data on select metrics, is widely used in the context of quality improvement. However, there is a lack of practical guidance describing the process of developing performance feedback systems. Initial Approach This study took place at University of California, San Francisco (UCSF) with hospitalist physicians. We used participatory design methodology to develop a performance dashboard and feedback system. Twenty hospitalist physicians participated in a series of six design sessions and two surveys. Each design session and survey systematically addressed key components of the feedback system, including design, metric selection, data delivery, and incentives. We then used the Capability Opportunity Motivation and Behavior (COM-B) model to identify behavior change interventions to facilitate engagement with the dashboard during a pilot implementation. Key Insights, Lessons Learned In regards to performance improvement, physicians preferred collaboration over competition and internal motivation over external incentives. Physicians preferred that the dashboard be used as a tool to aid in clinical practice improvement and not punitively by leadership. Metrics that were clinical or patient-centered were perceived as more meaningful and more likely to motivate behavior change. Next Steps The performance dashboard has been introduced to the entire hospitalist group, and we continue to evaluate implementation by monitoring engagement and physician attitudes. This will be followed by targeted feedback interventions to attempt to improve performance.
Mutual Fund Advisory Fees: New Evidence and a Fair Fiduciary Duty Test

A recent article in the Economist called attention to the mutual fund industry's flagrantly noncompetitive fee structure, noting that fund managers earn a "staggering" profit margin of 42% on average, largely because "most fund managers do not compete on price." Despite this reality, in a recent law review article based on research financed in part by the Investment Company Institute (a lobbying organization for fund sponsors), Professors John Coates and Glenn Hubbard purport to show that mutual fund managers compete vigorously on price and that fund shareholders are not suffering from price gouging over fund fees. The authors of the present article, "Mutual Fund Advisory Fees: New Evidence and a Fair Fiduciary Duty Test," beg to differ. Fund portfolio managers tend to charge their own shareholders double what they charge for essentially identical advisory services rendered to institutional investors in the free market. This reality raises severe fiduciary duty problems that the courts and the Securities Exchange Commission have so far proven unable or unwilling to solve. This new article proposes a better way of analyzing fund managers' fee contracts, relying on free market prices as a test for fairness, rather than comparisons based on conflicted, inflated fund market pricing. A Forbes writer noted some time ago that fund managers' "worst nightmare" would result if they were required to charge their funds' shareholders (to whom fiduciary duties are indisputably owed) prices based on the much lower portfolio management fees the fund managers charge when selling basically the same portfolio advisory services to third-party institutional clients in arm's-length transactions. The authors contend that a nightmarish outcome is exactly what price-gouging fund managers deserve.
Outbound Mergers and Acquisitions by Indian Firms

Changes to India’s laws governing Indian multinational corporations since the 1990s have had a significant impact on both the number and structure of cross-border acquisitions by Indian companies. This report discusses the legal reforms implemented by the government to help facilitate overseas acquisitions by Indian firms, the subsequent increase in outbound mergers and acquisitions, and the regulatory impediments that still exist to mergers and acquisitions by Indian firms.
Single‐Molecule Spectroscopy, Imaging, and Photocontrol: Foundations for Super‐Resolution Microscopy (Nobel Lecture)

The initial steps toward optical detection and spectroscopy of single molecules in condensed matter arose out of the study of inhomogeneously broadened optical absorption profiles of molecular impurities in solids at low temperatures. Spectral signatures relating to the fluctuations of the number of molecules in resonance led to the attainment of the single-molecule limit in 1989 using frequency-modulation laser spectroscopy. In the early 90s, many fascinating physical effects were observed for individual molecules, and the imaging of single molecules as well as observations of spectral diffusion, optical switching and the ability to select different single molecules in the same focal volume simply by tuning the pumping laser frequency provided important forerunners of the later super-resolution microscopy with single molecules. In the room temperature regime, imaging of single copies of the green fluorescent protein also uncovered surprises, especially the blinking and photoinduced recovery of emitters, which stimulated further development of photoswitchable fluorescent protein labels. Because each single fluorophore acts a light source roughly 1 nm in size, microscopic observation and localization of individual fluorophores is a key ingredient to imaging beyond the optical diffraction limit. Combining this with active control of the number of emitting molecules in the pumped volume led to the super-resolution imaging of Eric Betzig and others, a new frontier for optical microscopy beyond the diffraction limit. The background leading up to these observations is described and current developments are summarized.
T cell development: Some cells get all the breaks

Without Brca1, T cells are lacking in numbers and maturity, but surprisingly not because of a lack of repair of rearranged TCR genes. The defects involve more than one p53-dependent mechanism.
Analytical Evaluation of Spectral Moments and Dirlik’s Damage Model to Allow Comparison of Life Testing With Dissimilar PSD Vibration Curves

In the application of random vibration testing and the inverse power law to test products and extrapolate equivalent field life, the shape of the Power Spectral Density (PSD) vibration curve frequently introduces prediction errors and increased testing. A field PSD profile found to be highly dissimilar in shape to that used in the original accelerated testing raises questions of how to extrapolate equivalent life and often results in the need to repeat long duration vibration testing. Past work by the author has proposed utilizing the evaluation of zero crossings in two dissimilar PSD curves as a way to equate their testing impact and life predictions and therefore not require re-testing. This paper expands on this theory and explores utilization of spectral moments and Dirlik’s damage model to compare dissimilar PSD curves. Finite Element Analysis (FEA) and other analytical methods are utilized to expose a mechanical system to vibration inputs of different shapes, compute their fatigue life and then evaluate spectral moments and Dirlik’s damage model’s ability to account for dissimilar PSD curves.Copyright © 2014 by ASME
Clustering of Gephyrin at GABAergic but Not Glutamatergic Synapses in Cultured Rat Hippocampal Neurons

The molecular mechanisms underlying the establishment of a postsynaptic receptor mosaic on CNS neurons are poorly understood. One protein thought to be involved is gephyrin, a peripheral membrane protein that binds to the inhibitory glycine receptor and functions in clustering this receptor at synapses in cultured rat spinal cord neurons. We investigated the possible association of gephyrin with synapses in cultured rat hippocampal neurons, where glutamate and GABA but not glycine are the principal transmitters. Gephyrin immunoreactivity was detected in axons as well as dendrites, changing from a predominantly axonal to a more dendritic distribution with time in culture. Gephyrin staining was not distributed uniformly, but always took the form of clusters. Small clusters of gephyrin (0.2 microns 2), present throughout development, were distributed widely and not restricted to synaptic sites. Larger clusters of gephyrin (0.4-10.0 microns 2, sometimes composed of groups of small clusters), which developed in older cells, were localized to a subset of contacts between axons and dendrites. These large clusters were not present at glutamatergic synapses (marked by immunostaining for GluR1), but were closely associated with GABAergic synapses (marked by immunostaining for GABA and glutamic acid decarboxylase). These results, together with previous findings, suggest that gephyrin may function to anchor GABA and glycine receptors, but not glutamate receptors, at postsynaptic sites on central neurons. They also raise the possibility that gephyrin has additional functions, independent of its role at synapses.
Role of interfacial energy during pattern formation of electropolishing

This paper investigates the effect of interfacial energy on nanoscale pattern formation during electropolishing of aluminum. We correct a small error in the existing theory of Yuzhakov et al. that unfortunately no longer predicts stable hexagonal patterns. Upon including the interfacial energy in the derivation, the stable hexagons are recovered. We have derived the evolution equation of the aluminum interface during electropolishing and performed a linear and weakly nonlinear stability analysis. The results give values that lead to stable striped or hexagonal patterns. Results of a full nonlinear simulation of the evolution equation agree qualitatively with the weakly nonlinear results. Experimental results also verify our model, which predicts the coexistence of striped and hexagonal patterns in one sample.
Preparation of conducting composites of polypyrrole using supercritical carbon dioxide

Supercritical carbon dioxide, saturated with pyrrole, was brought into contact with oxidant-impregnated films of poly(chlorotrifluoroethylene) (PCTFE), crosslinked poly(dimethylsiloxane) (PDMS), poly(methyl methacrylate) (PMMA), and porous crosslinked polystyrene (PS) in order to form conducting composites via the in situ polymerization of pyrrole. The two nonporous hosts—PCTFE and crosslinked PDMS—did not form conducting composites with polypyrrole (PPy). On the other hand, the electrical conductivity of the PPy composites with carbon dioxide-swollen PMMA and porous PS ranged from 1.0 × 10−4 S/cm to 3.0 × 10−5 S/cm. In these two cases, the level of pyrrole polymerized on the surface or in the pores of the host polymer was sufficient to attain the interconnected conducting polymer networks necessary for electrical conductivity. © 2003 Wiley Periodicals, Inc. J Appl Polym Sci 90: 1113–1116, 2003
Practical applications of coherent transition radiation

Abstract The predictable nature of transition radiation (TR) emissions has been demonstrated under a wide variety of experimental conditions. The reliable character of TR allows the design of specific practical applications that use emissions from the optical to the X-ray spectral regions. Applications can often be enhanced by the spatial coherence of TR, and some have become highly developed. New applications may be developed through the use of other related radiation mechanisms.
Everyday Electrical Engineering: A One-Week Summer Academy Course for High School Students

A summer academy is held for grade 9-12 high school students at the University of Toronto, Toronto, ON, Canada, every year. The academy, dubbed the Da Vinci Engineering Enrichment Program (DEEP), is a diverse program that aims to attract domestic and international high school students to engineering and sciences (and possibly recruit them). DEEP also provides them with the opportunity to experience the university setting. This paper discusses the organization of DEEP and presents the details of a DEEP course developed to introduce students to electrical engineering. This course is designed for junior (grades 9 and 10) students and includes lectures, hands-on activities (both in a team and individually), and a field trip. The survey results, collected as both formative and summative feedback, indicate the success of the course. This paper also provides recommendations for future offerings of the course.
Islamic Fatalism and the Clash of Civilizations: An Appraisal of a Contentious and Dubious Theory

This paper will address the question of Islamic fatalism. Survey data will be used to assess Samuel P. Huntington's controversial "Clash of Civilizations" thesis and its emphasis on fatalism as an inherent characteristic of Islamic religion. The concept of fatalism is expanded and theorized as a function of both structural and theological dimensions. Findings here suggest that fatalism in the Islamic world remains a largely misunderstood phenomenon. Christians living in predominantly Muslim countries are no more fatalistic than their Muslim neighbors; and in Indonesia, Christians report higher levels of fatalism than Indonesian Muslims. However, Muslims do indicate a higher level of belief that cosmological forces control life's outcomes than do Christians living in those same Islamic societies. Findings also suggest that the effect of Western influence on fatalism is not as straightforward as that predicted by Huntington's theory. Fatalism in the Muslim world is best understood in light of complex historical, cultural, economic and socio-political processes and not as a direct outcome of Western influence and/or religious denomination alone.
The effect of gas evacuation on coal permeability test specimens

During permeability-stress experiments on coal-samples, it was observed that the process of gas evacuation caused a reduction in single-phase permeability. This paper examines possible causes of the phenomenon and outlines a method of avoiding it during laboratory testing.
The weight and processing quality of components of the storage roots of sugar beet (Beta vulgaris L.).

Studies in the 1970s showed that sugar beet partitioned into root, crown and scalp had large concentrations of impurities in the scalp, the root portion had the best processing quality and the crown was intermediate. Since then the processing quality of beet has improved. This paper reports similar studies on today's varieties, in an experiment at IACR-Broom's Barn over the three years 1993–1995, and extended in 1996 to the most important soil types used for sugar beet production in England. The crown is now a smaller proportion of the total beet weight (70 compared to 130 g kg−1) but the distribution of the concentrations of the quality parameters (sugar and the impurities potassium, sodium, amino nitrogen, raffinose, betaine and invert sugars) between the beet portions has not changed. This distribution was not significantly affected by year, variety or beet size but was affected by soil type. Nitrogen-rich soils produced beet with heavier crowns and a smaller differential in impurity concentration between the root and the crown. The scalp material had a variable sugar concentration, but it always contained large concentrations of impurities, especially invert sugar. The equation of Pollach et al (Zucker industrie116: 689–700 (1991)) which includes invert sugar as a variable, was applied to the data. It indicated that including all the crowns in the factory process with the roots would increase white sugar yield by approximately 6%. The increase due to inclusion of the scalp was much smaller (2%), and would probably be expensive to achieve. © 1999 Society of Chemical Industry
Relation of Flavor Development in Cheddar Cheese to Chemical Changes in the Fat of the Cheese

Abstract Typical Cheddar cheese flavor was found to be related to a balance of free fatty acids and acetate. Experimental lots of cheese, which had the finest flavor and highest score, had a concentration of free fatty acids plus acetate of 12 to 28 μ moles per gram of cheese solids after 180 days of aging or a ratio of free fatty acids to acetic acid between 0.55 to 1.0. Gas-liquid chromatography analysis showed that identical fatty acids were liberated in each lot of cheese. All even-numbered carbon fatty acids from C 4 to C 18 were found in each lot from the first day of manufacture. Cheese criticized as having rancid, fruity, and fermented flavors had two to three times the concentration of C 10 , C 12 , and C 14 fatty acids as did cheese of fine flavor. Cheese made from skimmilk did not acquire either Cheddar flavor or body characteristics during ripening of six or 12 months. Only Cheddar cheese containing 50% fat or more in the dry matter developed a typical flavor, whereas cheese with less than 50% fat did not. As fat in the cheese decreased, the concentration of fatty acids decreased, but the acetate increased so the ratio between free fatty acids/acetate became undesirable. Typical flavor developed in cheese made either from raw or from pasteurized whole milk, provided the bacterial count of the milk was not abnormally high or low. Greater concentration of free fatty acids developed during ripening in cheese made from pasteurized milk, when the total plate count was high in the raw milk,>10,000,000/milliliter, than in cheese made from raw milk with a low bacterial count, 1,000 to 5,000 /milliliter.
Some further studies on incubator reject eggs

Individual incubated and unincubated unfertilised eggs and 18-day incubator reject eggs have been measured by an improved assay for β-hydroxybutyric acid. Concentrations below 0.2 mg/100 g egg were found consistently for unfertilised eggs whether they had been incubated or not; 18-day incubator rejects included eggs with concentrations of β-hydroxybutyric acid up to 180 mg/100 g egg with a mean value of 13.8 mg/100 g egg. It is suggested that the different levels of β-hydroxybutyric acid can be approximately related to the embryological status of individual incubator reject eggs and the possible significance of this is discussed. Limiting the concentration of β-hydroxybutyric acid to not more than 0.2 mg/100 g in any sample of liquid whole egg would effectively preclude adulteration of fresh liquid whole egg with incubator reject eggs.
A subthreshold digital maximum power point tracker for micropower piezoelectric energy harvesting applications

Utilizing piezoelectric energy harvesting to power autonomous wireless sensors has garnered significant attention recently. However, because the generated power for small form-factor piezoelectric devices is on the order of 10 µW, the use of maximum power point tracking (MPPT) is imperative. Moreover, minimizing the power consumption of the maximum power point tracker is essential to increase the available power for the wireless sensor. To resolve this challenge, a digital MPPT controller is presented in this paper that is designed using subthreshold operation techniques. The MPPT controller is implemented and verified using a CMOS 0.35-µm process. The maximum power point tracker operates with a 1-V supply, consuming 3.71 µW while active. In addition, the proposed MPPT controller operates with 99.5% tracking efficiency.
Ultra-High Throughput Screen of Two-Million-Member Combinatorial Compound Collection in a Miniaturized, 1536-Well Assay Format

Results of a complete survey of the more than 2-million-member Pharmacopeia compound collection in a 1536-well microvolume screening assay format are reported. A complete technology platform, enabling the performance of ultra-high throughput screening in a miniaturized 1536-well assay format, has been assembled and utilized. The platform consists of tools for performing microvolume assays, including assay plates, liquid handlers, optical imagers, and data management software. A fluorogenic screening assay for inhibition of a protease enzyme target was designed and developed using this platform. The assay was used to perform a survey screen of the Pharmacopeia compound collection for active inhibitors of the target enzyme. The results from the survey demonstrate the successful implementation of the ultra-high throughout platform for routine screening purposes. Performance of the assay in the miniaturized format is equivalent to that of a standard 96-well assay, showing the same dependence on kinetic parameters and ability to measure enzyme inhibition. The survey screen identified an active class of compounds within the Pharmacopeia compound collection. These results were confirmed using a standard 96-well assay.
Lactoperoxidase-catalyzed activation of carcinogenic aromatic and heterocyclic amines.

Lactoperoxidase, an enzyme secreted from the human mammary gland, plays a host defensive role through antimicrobial activity. It has been implicated in mutagenic and carcinogenic activation in the ...
A new environment for teaching introductory computer science

In 1973, a great amount of frustration was being vented about student inability to formulate and solve problems on a computer; at that time, a suggestion was made to separate problem solving from programming—to make problem solving language independent [1].This approach was acknowledged in 1978 as one of four common methods of teaching college-level introductory computer science [2]. Finally, in 1981 and 1982, this method, or a variant of it, was widely proclaimed [3] [4] [5].We adopted this approach of instruction in our introductory course in 1977 and the results have been less than spectacular.We don't make this point to discredit the approach; its existence has made manifest the necessity of teaching problem solving in an introductory course. Rather, we believe that the added teaching of a separate problem solving methodology is not by itself sufficient.
Where Concepts Come from: Learning Concepts by Description and by Demonstration

Jerry Fodor’s arguments against the possibility of concept learning, and the responses that have been offered in defense of the coherence of concept learning, have both by and large assumed that concept learning is a descriptive process. I offer an alternative, ostensive approach to concept learning and explain how descriptive concept learning can be explained as a version of ostensive concept learning. I argue that an ostensive view of concept learning offers an empirically plausible and philosophically adequate account of concept learning that is explanatorily superior to traditional descriptive views.
Percutaneous management of postoperative lymphocele

A case report of a pelvic lymphocele developing after lymphadenectomy for staging of prostatic carcinoma is described. This collection was successfully managed by percutaneous catheter drainage. The incidence, pathophysiology, clinical symptomatology, differential diagnosis, and treatment options of pelvic lymphocele are reviewed. We believe that percutaneous catheter drainage is currently the optimal treatment modality.
Balancing the edge effects budget: bay scallop settlement and loss along a seagrass edge

Edge effects are a dominant subject in landscape ecology literature, yet they are highly variable and poorly understood. Often, the literature suggests simple models for edge effects—positive (enhancement at the edge), negative (enhancement at the interior), or no effect (neutral)—on a variety of metrics, including abundance, diversity, and mortality. In the marine realm, much of this work has focused on fragmented seagrass habitats due to their importance for a variety of commercially important species. In this study, the settlement, recruitment, and survival of bay scallops was investigated across a variety of seagrass patch treatments. By simultaneously collecting settlers (those viable larvae available to settle and metamorphose) and recruits (those settlers that survive some period of time, in this case, 6 weeks) on the same collectors, we were able to demonstrate a “balance” between positive and negative edge effects, resulting in a net neutral effect. Scallop settlement was significantly enhanced a...
Independent fission yields of Rb and Cs from $sup 238$U induced by fission- spectrum neutrons

The relative independent yields of Rb and Cs from $^{238}\mathrm{U}$ fission induced by fission-spectrum neutrons have been determined by means of a mass spectrograph on line with a nuclear burst reactor. The spectrograph ion source is a tantalum oven containing a target of high purity $^{238}\mathrm{U}$ in a graphite matrix. After irradiation, the radioactive fission products are deposited on the focal plane of the spectrograph and each mass position is analyzed quantitatively from its $\ensuremath{\beta}$ activities. Independent yields were calculated by normalizing the measurements using chain yield values and fractional independent yields that were calculated from recently measured cumulative yields for Kr and Xe. The results indicate a charge deviation from an unchanged charge distribution of 0.41 \ifmmode\pm\else\textpm\fi{} 0.07 nuclear charge units, a scaling factor of 1.27 for the number of neutrons associated with $^{238}\mathrm{U}$ fission over the prompt number from thermal-neutron fission of $^{235}\mathrm{U}$ for these fission products, and values of $\ensuremath{\sigma}$ for the isobaric charge distribution of 0.49 \ifmmode\pm\else\textpm\fi{} 0.04 and 0.60 \ifmmode\pm\else\textpm\fi{} 0.02 for Rb and Cs, respectively. An odd-even $Z$ effect is noticeable in that the fractional independent yields are generally lower by (20 \ifmmode\pm\else\textpm\fi{} 10)% for both Rb and Cs than the mean values estimated from a smooth theoretical model. The sum of the estimated independent yields for the Rb isotopes agrees within error with that for the isotopes of the complementary element Cs.NUCLEAR REACTIONS $^{238}\mathrm{U}(n,f)$, $E=\mathrm{fission}\mathrm{spectrum}$; measured relative abundances; deduced independent fission yields, charge deviation, odd-even $Z$ effect. Mass spectrograph, burst reactor.
Evaluating the technological properties of powders from their dielectric permeability

The assessment of the properties of powders used for making refractories is discussed. Because the existence of an integral influence of macro- and microparameters on the properties of the goods requires an extension of the range of defined parameters for the powders, the authors study the dielectric characteristics of powders and their influence and interaction with the properties of the resulting products. The objectives of the research consisted of two samples (D and V) of powdered fused periclase with mass proportions of magnesia of about 97%. The results of determining the grain-size composition of the two powders were obtained by the sedimentation method on the VSA-500 apparatus. The measured dielectric permeability of the mixture of powder and air was extrapolated for the compacted body from an equation. The technological properties of these powders were determined by preparing three groups (I, II, and III) of specimens. Results of the tests show that on the basis of the measurements of the dielectric permeability it is possible to assess operationally the technological properties of powders used for preparing bodies.
Confocal assay for invasion: use of propidium iodide fluorescence and laser reflectance to quantify the rate of migration of cells through a matrix.

Background Most assays used to measure invasion are based on manual counting of the number of cells that have migrated completely through commercial coated filters. We describe here a confocal fluorescence-imaging method that can assess the relative rates of invasion of cells into a matrix. Methods After being seeded on the matrix and a period of incubation, the cells are fixed and treated with RNase. Propidium iodide is then added to stain the double-stranded DNA. A confocal microscope system is used to obtain high-resolution images of the red propidium iodide fluorescence and laser reflectance from optical sections at increasing depths in the matrix. The section with high laser reflectance marks the top of the matrix. Results Data were calculated as the total area of red fluorescence above background in each section and were plotted as a percentage of the summed fluorescent areas in all sections. Conclusions Because the distance into the matrix of the nuclei can be calculated by measuring from the reflective upper surface of the matrix, the method is useful for assessing the rate of cell migration and for comparing the ability of different cells to invade through different matrices under varying conditions. Cytometry 40:253–259, 2000 © 2000 Wiley-Liss, Inc.
Role of cracks in the creep deformation of brittle polycrystalline ceramics

A discussion is presented of the effect of cracks formed during the creep deformation of polycrystalline ceramics on the rate of creep deformation. Four distinct regions of the creep curve are identified. In region I, creep is controlled by the basic creep mechanism without cracks. Creep in region II is the combined effect of elastic creep by crack growth due to time-dependent changes in elastic properties and crack-enhanced creep described by Weertman. I n region III, in which the cracks have reached their final size, the rate of creep is governed by the sole effect of crack-enhanced creep. Region IV, not discussed in detail, is represented by accelerated creep due to crack coalescence prior to failure. The apparent stress exponent of crack-enhanced creep is shown to be governed by the value of the stress exponent of the basic creep mechanism as well as the stress dependence of the number of cracks formed per unit area or volume. The dependence of crack density on grain size also modifies the grain-size dependence of Nabarro-Herring and Coble creep. Depending on the specific mechanism of crack growth, region II creep can exhibit an apparent activation energy which can differ from the corresponding values for region I and III creep. Detailed microstructural information on crack size, crack density and other relevant variables is required for the quantitative analysis of the creep kinetics of polycrystalline ceramics subject to crack formation.
Predictors of relationship quality during the transition to parenthood

Objective: The present study examined predictors of relationship quality among a sample of first-time parents. Background: The transition to parenthood engenders both joys and challenges for parents and has been a focus of interest to scholars for decades. On average, couple relationship quality declines following the birth of a first child, but research has moved beyond averages and focused instead on uncovering factors that lead some couples to improve in relationship quality and others to decline. Methods: Using data collected from 29 first-time parent dyads, this short-term longitudinal study examined the ways in which similarity between mothers’ and fathers’ role expectations at birth, similarity of individual parents’ ideal versus actual parenting responsibilities at six months, and parents’ satisfaction with the division of childrearing responsibilities at six months were related to parents’ reports of relationship quality at child age six months. Results: Regressions revealed that mothers’ relatio...
Ethical leadership and group in-role performance: The mediating roles of group conscientiousness and group voice

Abstract In this paper, we propose that ethical leadership will lead to higher group in-role performance. Building from and integrating several different research streams, we argue that two key mechanisms for this effect are group conscientiousness (an emergent state) and group voice (a group process). We collected survey data at three points in time from 80 groups of nurses and the groups' leaders. The results provide support for all of our hypotheses. There was a positive relationship between employee ratings of ethical leadership (Time 1) and leader ratings of group in-role performance (Time 3). Group conscientiousness and group voice (Time 2) both partially mediated this relationship. These results contribute to our understanding of leadership and group effectiveness not only by showing that ethical leadership has a positive influence on group in-role performance, but also by identifying specific norms and group-level behaviors that help to account for this relationship.
Statistical estimation of multiple parameters via symbolic dynamic filtering

This paper addresses statistical estimation of multiple parameters that may vary simultaneously but slowly relative to the process response in nonlinear dynamical systems. The estimation algorithm is sensor-data-driven and is built upon the concept of symbolic dynamic filtering for real-time execution on limited-memory platforms, such as local nodes in a sensor network. In this approach, the behavior patterns of the dynamical system are compactly generated as quasi-stationary probability vectors associated with the finite-state automata for symbolic dynamic representation. The estimation algorithm is validated on nonlinear electronic circuits that represent externally excited Duffing and unforced van der Pol systems. Confidence intervals are obtained for statistical estimation of two parameters in each of the systems.
Effect of sampling site on assessment of pulmonary artery blood flow by Doppler echocardiography

Abstract Pulmonary artery (PA) blood flow recordings by Doppier echocardiography have been used to estimate PA pressure 1,2 and calculate cardiac output. 3 Peak velocity and time to peak velocity (TPV) measurements of PA flow, however, may vary with different views, transducer or beam angulation and sampling sites. 4,5 We examined the effect of sampling site of pulsed mode Doppler on the PA blood flow characteristics.
Streptokinase and Heparin in the Treatment of Pulmonary Embolism: A Randomized Comparison:

Treatment with streptokinase followed by heparin was compared on a randomized basis with treatment with heparin alone in patients with acute pulmonary embolism. The diagnosis and results of treatment were established by pulmonary angiography. Fifteen patients received streptokinase and 16 received heparin alone. Complications included bleeding and pyrexia in both treatment groups and anaphylaxis in a patient receiving streptokinase. There were three deaths attributed to the disease its treatment. Patients in the strepto kinase group had significantly greater angiographic improvement (P = 0.0125) than those in the heparin group.
DNA homologies among homothallic, pseudo-homothallic and heterothallic species ofNeurospora

Highly purified DNAs from three homothallic speciesNeurospora africana, N. dodgei andN. lineolata; three reference strains representing authentic heterothallic species,N. crassa, N. intermedia andN. sitophila; and two strains of pseudo-homothallic speciesN. tetrasperma were characterized by spectrophotometry and DNA reassociation using hydroxyapatite chromatography. All of these known species are closely related on the basis of DNA characteristics such as base composition and thermal denaturation profiles of major DNA components. Minor components of ascospore DNA was, however, only 5–7% of total DNA instead of 15–20% minor component DNA shown by mycelial DNA. Species belonging to same group were not distinguishable morphologically, but all of these species were distinguishable by DNA:DNA homology studies. Greater DNA homology was noticed between DNAs of heterothallic species and DNAs of pseudohomothallic species than DNA of true homothallic species. Difference on DNA-nucleiotide sequences among homothallic species was very little. Pseudo-homothallic speciesN. tetrasperma was found to be distinctly different from homothallic species but closer to heterothallic species based on such studies.