cssi/SciSciGPT-SciSciNet huggingface dataset:
Genetic diversity within vertebrate species is greater at lower latitudes

The latitudinal gradient of species diversity is one of the oldest recognized patterns in biology. While the cause of the pattern remains debated, the global signal of greater diversity toward the tropics is widely established. Whether the pattern holds for genetic diversity within species, however, has received much less attention. We examine latitudinal variation of intraspecific genetic diversity by contrasting nucleotide distance within low- and high-latitude animal groups. Using mitochondrial DNA markers across 72 vertebrate species that together span six continents, two oceans, and 129 degrees of latitude, we found significantly greater genetic diversity at low latitudes within mammalian species, and trends consistent with this pattern in reptiles, amphibians, fish, and birds. The signal held even after removing species whose current geographic ranges include areas recently covered by glaciers during the late Pleistocene and which presumably have experienced colonization bottlenecks in high latitudes. Higher genetic diversity within species was found at low latitudes also for genera that do not possess higher species richness toward the tropics. Moreover, examination of a subset of species with sufficient sampling across a broad geographic range revealed that genetic variation demonstrates a typical gradient, with mid-latitude populations intermediate in genetic diversity between high and low latitude ones. These results broaden the pattern of the global latitudinal diversity gradient, to now include variation within species. These results are also concordant with other studies indicating that low latitude populations and species are on different evolutionary trajectories than high latitude ones, and we speculate that higher rates of evolution toward the equator are driving the pattern for genetic diversity within species.
Use of Partially Fenced Fields to Reduce Deer Damage to Corn

White-tailed deer (Odocoileus virginianus) damage agricultural crops, often leading to signifi- cant economic losses for farmers. We used poly-mesh fence with wings to separate good deer cover from agricultural fields where crop damage by deer occurred primarily along this edge. In these cases, complete enclosure of the field with fencing may be unnecessary. The design used a 2.13-m-high polypropylene mesh fence erected along the wooded edge of a field with either 50-m or 150-m wings extending perpendicular from the fence line and wooded habitat. Fences reduced deer damage in cornfields 13.5% (F1,6 ¼1 , P < 0.001). Average yield in fenced fields (10,211 kg/ha) was 1,708 kg/ha greater than in control fields, which, at US$0.155/kg, equals a net gain of US$265/ha. We found no difference in damage between fences with 50-m and 150-m wings (F1,1 ¼ 0.26, P ¼ 0.695). Costs for materials and labor for erecting partial poly-mesh fences with wings were US$5.56/m and US$1.42/m, respectively. Mean total cost for partial poly-mesh fences with 50-m wings would be US$60.13/ha/year over a 10-year period, compared with US$82.30/ha/year for 150-m wings and US$184.16/ha/year for completely enclosing fields. Expected savings for partial poly-mesh fences with 50-m wings over a 10-year period were US$205/ha/year, as compared with damaged fields without fences. We concluded that poly-mesh fences with 50-m wings were cost-effective at reducing damage by deer to corn. Additional research should be conducted to determine efficacy of the more cost-effective high-tensile and poly-tape fences with wings. 2012 The Wildlife Society.
C4 Plant Productivity and Climate-CO2 Variations in South-Central Texas during the Late Quaternary

A continuous record of organic carbon δ13C from a buried soil sequence in south-central Texas demonstrates: 1) strong coupling between marine and adjacent continental ecosystems in the late Pleistocene as a result of glacial meltwater entering the Gulf of Mexico and 2) ecosystem decoupling in the Holocene associated with a reduction of meltwater and a shift in global circulation patterns. In the late Pleistocene, reduction in C4 plant productivity correlates with two well-documented glacial meltwater pulses (∼15,000 and 12,000 14C yr B.P.), indicating a cooler-than-present adjacent continental environment. Increased C4 production between 11,000 and 10,000 14C yr B.P. suggests that the Younger Dryas was a warm interval responding to the diversion of glacial meltwater away from the Mississippi River. With waning meltwater flow, C4 productivity generally increased throughout the Holocene, culminating in peak warm intervals at ∼5000 and 2000 14C yr B.P. Shifts in the abundances of C3–C4 plants through the late Quaternary show no correlation to ecophysiological responses to atmospheric CO2 concentration.
Regulatory potential, phyletic distribution and evolution of ancient, intracellular small-molecule-binding domains.

Central cellular functions such as metabolism, solute transport and signal transduction are regulated, in part, via binding of small molecules by specialized domains. Using sensitive methods for sequence profile analysis and protein structure comparison, we exhaustively surveyed the protein sets from completely sequenced genomes for all occurrences of 21 intracellular small-molecule-binding domains (SMBDs) that are represented in at least two of the three major divisions of life (bacteria, archaea and eukaryotes). These included previously characterized domains such as PAS, GAF, ACT and ferredoxins, as well as three newly predicted SMBDs, namely the 4-vinyl reductase (4VR) domain, the NIFX domain and the 3-histidines (3H) domain. Although there are only a limited number of different superfamilies of these ancient SMBDs, they are present in numerous distinct proteins combined with various enzymatic, transport and signal-transducing domains. Most of the SMBDs show considerable evolutionary mobility and are involved in the generation of many lineage-specific domain architectures. Frequent re-invention of analogous architectures involving functionally related, but not homologous, domains was detected, such as, fusion of different SMBDs to several types of DNA-binding domains to form diverse transcription regulators in prokaryotes and eukaryotes. This is suggestive of similar selective forces affecting the diverse SMBDs and resulting in the formation of multidomain proteins that fit a limited number of functional stereotypes. Using the "guilt by association approach", the identification of SMBDs allowed prediction of functions and mode of regulation for a variety of previously uncharacterized proteins.
Synthesis of the modeling and control systems of a tunneling accelerometer using the MatLab simulation

In this paper, we construct the function model of a tunneling accelerometer using MatLab Simulink. With small input signal approximation, the tunneling current and electrostatic actuator nonlinear blocks are analyzed and linearized. From the derived relation between open and close loop transfer functions, we synthesize a simple but effective way to design the control system. By choosing a control system, the accelerometer bandwidth is broadened and the damping is enhanced. The system stability, root locus, step response, gain and phase margins, and pole-zero distribution are all plotted and discussed. With the designed control and feedback systems, a close loop system is stable on both parameter disturbance and frequency response. Compared with the real system at 50 ng Hz−1/2 noise level, we also present tunneling accelerometer characteristics, such as the exponential relationship between tunneling current and displacement change, time history record, dynamics and frequency response.
Fabrication of inverted opal ZnO photonic crystals by atomic layer deposition

We have fabricated three-dimensional optically active ZnO photonic crystals by infiltrating polystyrene opal templates using a low-temperature atomic layer deposition process. The polystyrene is removed by firing the samples at elevated temperatures, and reactive ion etching is used to remove the top layer of ZnO and expose the (111) photonic crystal surface. The resulting structures have high filling fractions, possess photonic band gaps in the near-UV to visible spectrum, and exhibit efficient photoluminescence.
Operative Pulmonary Artery Pressure Measurements as a Guide to Postoperative Management and Prognosis following Pneumonectomy

SUMMARY Operative pulmonary artery pressure measurements have been obtained on 61 patients undergoing pneumonectomy. Correlations are made of these pressure measurements with postoperative survival and fatal complications. The average mean pulmonary artery pressure in all survivors was 22 mm.Hg and increased to 26 mm.Hg after occlusion. The average mean pulmonary artery pressure in patients developing fatal cardiorespiratory complications was 28 mm.Hg and after occlusion 32 mm.Hg. A simple technique is described to enable the surgeon to assess the status of the pulmonary circulation at the time of surgery. It is concluded that patients in whom mean pulmonary artery pressures are 25 mm.Hg or greater at surgery and in whom "abnormal" preoperative pulmonary function studies have been obtained should have the operative procedure modified or vigorous medical management instituted postoperatively.
JNN captures 40 years of pharmacology.

Each 2008 issue of the Journal of Neuroscience Nursing includes an anniversary feature in which we celebrate the vision, determination, and challenges that have marked 4 decades of neuroscience nursing practice and publishing excellence. We will highlight our past and begin to envision our future as we examine the changes we have witnessed.
America's deadly export: Evidence from cross-country panel data of deportation and homicide rates

Abstract Changes in US Immigration laws between the mid-1980s to the late 1990s led to a sharp increase in criminal deportations. During the same years many poor countries, especially in Latin America and the Caribbean, experienced a sharp increase in homicides. Using panel data for a sample of 38 developed and developing countries, I find a statistically significantly positive relationship between an increase in the number of criminal deportees received by a country and a corresponding increase in that country's homicide rate, and I establish causality through instrumental variables. My analysis suggests that about 23 percent of the increase in the homicide rate in developing countries between 1985 and 1996 can be attributed to the increase in the inflow of criminal deportees from the United States.
Field and laboratory methods in human milk research

Human milk is a complex and variable fluid of increasing interest to human biologists who study nutrition and health. The collection and analysis of human milk poses many practical and ethical challenges to field workers, who must balance both appropriate methodology with the needs of participating mothers and infants and logistical challenges to collection and analysis. In this review, we address various collection methods, volume measurements, and ethical considerations and make recommendations for field researchers. We also review frequently used methods for the analysis of fat, protein, sugars/lactose, and specific biomarkers in human milk. Finally, we address new technologies in human milk research, the MIRIS Human Milk Analyzer and dried milk spots, which will improve the ability of human biologists and anthropologists to study human milk in field settings.
Nonepileptic Seizures: Psychiatric Aspects

Abstract Nonepileptic seizures are events seen relatively commonly by neurologists in general and by epilepsy centers in particular. Once the diagnosis is made, etiology needs to be determined. One might think that etiology would easily lead to effective treatment, but this often is not the case. This article reviews the literature on the diagnosis and treatment of these disorders.
The natural history of early recurrent carotid artery stenosis

Abstract BACKGROUND: Early recurrent carotid stenosis, defined as greater than 50% stenosis within 2 years of a carotid endarterectomy (CEA), occurs in 4% to 19% of patients. These lesions are secondary to myointimal hyperplasia (MH). The natural history of these lesions has been examined prospectively, but the appropriate management of these lesions has not been clearly defined. The vascular surgery service at Madigan Army Medical Center (MAMC) has prospectively collected a cohort of patients with recurrent high-grade carotid stenoses following CEA to determine their natural history and define the ideal therapeutic approach for those lesions. METHODS: Patients undergoing CEA between January 1, 1993, and January 1, 1997, at a single tertiary care institution were followed prospectively with postoperative carotid duplexes at 3-month intervals for the first year and then every 6 months for a year and then annually thereafter. Data were collected regarding patient demographics, type of carotid closure, neurologic morbidity, and death. These results were compared with accepted rates in the literature. Discrete variables were tested for significance by chi-square analysis and Fisher’s exact test. A P value less than or equal to 0.05 was considered significant. RESULTS: One hundred and seventy-four (174) patients with 181 operative sites were evaluated. Fourteen patients with 17 sites (9%) had recurrent stenosis. Twelve patients with 14 sites (7%) had stenoses of 50% to 79%. All were asymptomatic. Two patients with 3 sites (2%) had stenoses greater than 80%. Two sites were managed operatively because of neurologic symptoms or preocclusive nature and one remains asymptomatic and stable on serial duplex imaging. All lesions were present at 6 months and those in the 50% to 79% category did not progress in follow-up. Recurrent carotid stenosis occurred to a significantly higher degree in women (women 11 of 60 18.3% versus men 6 of 114 5.3%; P = 0.25), primary closure versus patch angioplasty (primary 6 of 22 27.3% versus patch 11 of 159 6.9%; P = 0.01), and dacron versus polytetrafluoroethylene (PTFE) patch angioplasty (dacron 7 of 36 19.4% versus PTFE 2 of 100 2.0%; P = 0.02). CONCLUSION: Early recurrent stenosis (50% to 79%) is a benign lesion. Patch angioplasty is preferred over primary closure. Dacron patches had a significantly higher rate of recurrent stenosis when compared with PTFE patches. Women undergoing CEA are more prone to recurrent stenosis. Postoperative duplex at 3 and 6 months will identify recurrent carotid stenosis (given a normal duplex prior to discharge following CEA). Moderate high-grade (50% to 79%) stenoses are benign. High-grade (80% to 99%) stenoses require individual management.
Xenopus as an Experimental Organism

The South African clawed frog, Xenopus laevis, is used extensively as a model system to study development. Its advantages include the ease of maintaining a breeding colony of frogs and of obtaining and manipulating their embryos. Keywords: frog; embryology; animal care; metamorphosis; cell cycle
Interrupt and low-level programming support for expanding the application domain of statically-scheduled horizontal-microcoded architectures in embedded systems

The increasing role of software in the embedded systems has made processor an important component in these systems. However, to meet the tight constraints of embedded application, it is often required to customize the processor for the application. Customizing instruction-based processors is difficult and very challenging. Design approaches based on statically-scheduled horizontal-microcoded architectures have been proposed to simplify the architecture customization. In these approaches, first the datapath is specified by the designer, and then the operations of the datapath are extracted automatically. Since the operations are statically scheduled in these architectures (i) low-level programming using assembly is impossible or very tedious; and (ii) execution of programs cannot be interrupted arbitrarily. This paper addressed the above problems. The paper shows how to efficiently handle interrupts in such architectures and also propose an elegant way of controlling low-level hardware resources in a general way in C language. The authors also show that after adding interrupt and low-level programming that could use the above architectural style in a multi-core system to implement a complete MP3 decoder that can process 122 frames per second while the standard requirement is 38 frames per seconds
Constrained Nonlinear Optimization by Heuristic Programming

This paper develops a new algorithm for solving the general nonlinear programming problem that melds the flexible simplex search of Nelder and Mead with various additional rules to take care of equality and/or inequality constraints. The set of violated inequalities and equalities is lumped into one inequality constraint loosely satisfied during the early progress of the optimization and more closely satisfied during its final stages. To permit this type of search, the method sets up a special tolerance criterion, a function that does not depend on either the values of the objective function or the values of the constraints. The new algorithm has solved successfully a number of problems that have been proposed in the literature as test problems. Finally, to indicate the algorithm's capabilities, the paper describes an example composed of a linear objective function of twenty-four variables subject to fourteen nonlinear equalities and thirty inequalities.
Regulated release of VWF and FVIII and the biologic implications

von Willebrand factor (VWF) performs a critical function in platelet binding at the site of vascular injury and also serves as the carrier protein for coagulation factor FVIII (FVIII), protecting it from proteolytic degradation in plasma. Both proteins undergo rapid, regulated release in response to DDAVP administration in patients with mild hemophilia A or von Wille-brand disease. Here, we attempt to summarize our current understanding of the establishment of the regulated storage pool of VWF and FVIII. The data presented indicate that regulated secretion of both proteins occurs only if there is endogenous synthesis of FVIII together with VWF.
Cooperative learning: Applying contact theory in desegregated schools.

This paper reviews research on instructional methods designed to operationalize the principal elements of Allport's (1954) contact theory of intergroup relations. These cooperative learning methods employ ethnically mixed learning groups, who study material presented by the teacher and are rewarded based on the learning of the group as a whole. Field experimental research on these methods in desegregated elementary and secondary schools has found relatively consistent positive effects on intergroup relations, as well as on the achievement of minority and majority students. The implications of this research for contact theory and for instruction in desegregated classrooms are discussed in light of the research evidence.
Child Support and Subsequent Nonmarital Fertility With a New Partner

When a parent has another child with a new partner, a significant effect on parents and children is likely, making factors associated with multiple-partner fertility of interest to policy makers. For single mothers, one potential policy-relevant factor influencing their subsequent fertility with a new partner is child support income. However, the direction and magnitude of any effect is not well-established. This study documents the simple negative relationship between child support and nonmarital fertility with a new partner in our sample of low-income unmarried mothers. We then take advantage of a policy experiment that resulted in randomly assigned differences in child support income to investigate its effects. We find no support for a negative causal relationship between child support receipt and nonmarital fertility with a new partner, instead finding suggestive evidence that mothers with more child support income are slightly more likely to have a subsequent nonmarital birth with a new partner.
Chemical and thermal characterization of potato peel waste and its fermentation residue as potential resources for biofuel and bioproducts production

The growing demand for renewable fuels has driven the interest in the utilization of alternative waste materials such as potato peel waste (PPW) which contains fermentable carbohydrate. Fermentation of PPW using a mixed microbial consortium yielded about 60% unreacted PPW fermentation residue (PPW-FR). The PPW and PPW-FR were characterized by a combination of Fourier transform infrared (FTIR) and nuclear magnetic resonance (NMR) spectroscopies, gas chromatography-mass spectrometry (GC-MS), and thermogravimetric analysis (TGA) to quantify changes after fermentation. Fermentation of PPW resulted in fermentation of starch and concentrating lignin plus suberin and lipids in PPW-FR. TGA analysis showed that decomposition peaks differed for PPW (423 °C) and PPW-FR (457 °C). Pyrolysis-GC/MS showed an increase in phenolic and long chain fatty acid compounds with a concomitant decrease in carbohydrate derived compounds in the PPW after fermentation. Both the PPW and PPW-FR have shown potential based on properties to be converted into crude biofuel via thermochemical processes.
Information content of female chemical signals in the wolf spider, Schizocosa ocreata: male discrimination of reproductive state and receptivity

Fine-scale information content of chemical signals has been widely studied in several vertebrate taxa and in social and economically important invertebrate taxa but remains poorly understood for many invertebrate predators such as spiders. Chemical signals (e.g. pheromones) associated with spider silk may convey information about species identity, sex, age and/or reproductive status of a female to male receivers. In the wolf spider Schizocosa ocreata (Hentz), females are cryptic within the leaf-litter habitat, are potentially aggressive and/or cannibalistic depending on reproductive status and age, and do not appear to communicate their status to males using seismic or visual signals. Hence, males are expected to exploit female chemical signals to discriminate among potential mates. We used behavioural assays to determine whether male S. ocreata can discriminate potentially receptive mates using cues associated with female silk. Males were presented with silk from females that varied in reproductive status and/or potential receptivity. Males showed significantly more and longer bouts of chemosensory and courtship behaviours, with significantly reduced latency, on the silk of adult, unmated female spiders than on any other stimulus treatment, including the silk of subadult and mated females. Additionally, male S. ocreata responded less to the silk cues of females that were within 1 week prior to maturity and the silk of females that had recently moulted (females up to 1 week old). This is significant, as females show increased aggression to males during their first week of adulthood and after mating. Thus, males clearly possess the ability to assess reproductive status as well as age-related potential receptivity of conspecific females based on cues associated with silk.
Vasopressor use after initial damage control laparotomy increases risk for anastomotic disruption in the management of destructive colon injuries

Abstract Background Management of destructive colon injuries during damage control (DC) laparotomy is debated. The authors reviewed a single institution's experience with destructive colon injuries to identify risk factors for anastomotic failure after colon reconstruction. Methods The authors identified all trauma patients sustaining destructive colon injuries between 2002 and 2011 from their medical center's trauma registry. Anastomotic leak was defined as suture or staple line disruption or enteral fistula formation. Results Of 171 identified patients, 68 had DC procedures, 41 (60%) had subsequent anastomoses performed during the same hospitalization, and 27 (40%) were diverted. The colon anastomotic leak rate in patients who underwent DC laparotomy was higher than in patients who were reconstructed at the primary operation in a non-DC setting (17% vs 6%, P = .09). The use of vasopressors after the initial DC operation more than quadrupled the leak rate to 50% ( P = .02). Conclusions Colonic anastomotic disruptions yield deadly consequences, and diversion rather than anastomosis should be used in patients who require vasopressor support after the initial DC procedure.
Analysis of proopiomelanocortin gene expression during prenatal development of the rat pituitary gland.

The POMC gene is transcribed in 5–10% of adult rat anterior pituitary cells and nearly all intermediate lobe cells, but the end product peptide hormones produced by these two cell populations are distinct. We have here used in situ hybridization with 3HPOMC cRNA probes to investigate the temporal and spatial distribution of POMC mRNA containing cells during development of both lobes of the adenohypophysis. These hybridization patterns were, in addition, compared to the immunocytochemical distribution of POMC-related peptides on the same or adjacent sections. In both POMC populations, POMC-mRNA detection preceded POMC-derived peptide accumulation by at least 0.5 days. POMCmRNA was first detected in the ventral aspect of Rathke's pouch (which will give rise to the anterior lobe) at e13, which was two days earlier than POMC transcripts were first detected in the intermediate lobe; this result provides strong evidence that factors eliciting POMC transcription in these two populations act at distinct times dur...
Optical Microwave Frequency Up-Conversion Via a Frequency-Doubling Optoelectronic Oscillator

We propose and demonstrate an optical microwave modulator that incorporates a low phase-noise optoelectronic oscillator (OEO) for frequency up-conversion in a radio-over-fiber system. A single Mach-Zehnder lithium-niobate waveguide modulator working as a local oscillator in a frequency-doubling OEO directly up-converts the baseband signals to a carrier band. We demonstrate frequency up-conversion to the 20-GHz band for optical analog signals in the intermediate-frequency (IF) band and for optical digital signals at 1.25 Gb/s. The measured transmission bandwidth for IF modulated signals is greater than 1.5 GHz for transmission over 50.5 km of single-mode fiber.
3D Architectured Anodes for Lithium-Ion Microbatteries with Large Areal Capacity

Progress in the miniaturization of batteries has lagged well behind that of microelectronics. Although lithium-ion (Li-ion) battery technology has been vital in advancing portable consumer electronics, it is not clear whether future generations of microscale devices can be powered using traditional battery designs. In this paper, we report on the fabrication and properties of battery electrodes comprised of arrays of vertically aligned carbon rods. The electrodes exhibit good reversibility and represent the first carbon arrays to achieve areal capacities greater than 5 mAh cm−2 at relatively large current densities, although the capacity does fade with cycling. The 3D battery designs based on these architectures offer the promise of achieving high energy densities within small footprint areas.
Beryllium-10 terrestrial cosmogenic nuclide surface exposure dating of Quaternary landforms in Death Valley

Quaternary alluvial fans and shorelines, spits and beach bars were dated using 10 Be terrestrial cosmogenic nuclide (TCN) surface exposure dating in Death Valley. The 10 Be TCN ages show considerable variance on individual surfaces. Samples collected in the active channels date from ~ 6 ka to ~ 93 ka, showing that there is significant inheritance of 10 Be TCN within cobbles and boulders that were dated, which suggests that slopes erode and sediment is transferred very slowly in most regions within Death Valley. Comparisons of 10 Be TCN ages on alluvial fan surfaces with chronostratigraphies based on soil development and optically stimulated luminescence dating show that minimum 10 Be TCN ages within sample sets on individual surfaces most closely approximate to the age of landforms that are younger than ~ 70 ka. Alluvial fan surfaces older than ~ 70 ka have begun to undergo significant erosion so that the majority of 10 Be TCN ages for data sets on individual surfaces underestimate the true age of the surface due to erosion and exhumation of fresh cobbles and boulders. The spread of 10 Be TCN ages for beach bars near Beatty Junction and shorelines ~ 8 km south of Furnace Creek is large, ranging from ~119 ka to ~ 385 ka and ~ 109 ka to ~ 465 ka, respectively. However, new and previously published luminescence ages, soil development and geomorphic context suggest that these landforms formed during high lake level stands in marine isotope stage 2 (~ 22-18 ka), but these younger ages my reflect soil development and material elluviated into the bar deposit long after deposition. This suggests that the cobbles and boulders dated with 10 Be methods have inherited 10 Be TCNs, which have been derived from older shorelines or associated landforms. These results highlight the problems associated with using surface cobbles and boulders to date Quaternary surfaces in Death Valley and other similar dryland settings. Moreover, this study emphasizes the need to combine multiple, different dating methods to accurately date landforms in Death Valley and similar settings.
Investigating the Relationship of Resilience to Academic Persistence in College Students With Mental Health Issues

In this study, the relationships between measures of inter- and intrapersonal resilience and mental health were examined with respect to academic persistence in college students with mental health ...
A modified stepwise linear regression method for estimating modal sensitivity

Small signal stability problems are one of the major threats to grid stability and reliability. Low damping of inter area modes is usually considered to be a result of heavy power transfer over long distances. This paper proposes a modified stepwise regression method to estimate the modal sensitivity with respect to power flow on the transmission lines based on measurement. This sensitivity is used to identify dominant transmission lines, whose power flow has significant influence on the inter-area modal damping. It is shown through simulation study that the proposed method can effectively estimate the modal sensitivity with respect to line power flow. This, in turn, provides insight on how to improve damping through adjusting tie line flow.
Saturation mutagenesis of Asn152 reveals a substrate selectivity switch in P99 cephalosporinase

In class C β-lactamases, the strictly conserved Asn152 forms part of an extended active-site hydrogen-bonding network. To probe its role in catalysis, all 19 mutants of Enterobacter cloacae P99 cephalosporinase Asn152 were simultaneously constructed and screened in Escherichia coli for their in vivo activity. The screen identified the previously uncharacterized mutants Asn152Ser, Asn152Thr, and Asn152Gly, which possess significant activity and altered substrate selectivity. In vitro measurement of Michaelis-Menten kinetic constants revealed that the Asn152Ser mutation causes a selectivity switch for penicillin G versus cefoxitin. Asn152Thr showed a 63-fold increase in k cat for oxacillin, a slow substrate for wild-type cephalosporinase. The results contribute to a growing body of data showing that mutation of highly conserved residues in the active site can result in substrate selectivity changes. The library screening method presented here would be applicable to substrate selectivity determination in other readily screenable enzymes.
Quantum molecular dynamics simulation of proton transfer in cytochrome c oxidase.

Abstract Proton transfer/translocation is studied in cytochrome c oxidase (CcO) by a combination of quantum mechanics (QM) for the transferring protons and classical molecular dynamics (MD) for the protein and solvent. The possibility of a glutamate, Glu286 in the Rhodobacter sphaeroides numbering scheme, acting as a rely point for proton translocation is investigated. The MD finds a hydrogen-bonded cycle of two waters and the carboxylate oxygens of Glu286. The possibility of protonating Glu286 to form neutral GluH is studied and we find that, as experimentally inferred, this glutamate can spend most of its time as GluH. Since translocation relies on the presence of water chains within CcO channels, MD is used to assess their formation. Glu286 and Mg2+ can be connected by continuous hydrogen-bonded chains that are robust, though transient, and the protein appears spongy above (toward the outer membrane) the Mg2+. In contrast, the D-channel spanning Asp132, close to the inner membrane surface, to Glu286, forms water chains that are much sparser and do not continuously connect these residues. Rather, there are chains spanning Glu286 to the vicinity of Asn140, and other more robust and ramified water structures that connect Asp132 with waters close to Asn140.
A New Nomenclature for Psychotropic Drugs.

Introduction Current classifications of psychotropic drugs, developed in the 1960s, are based on beliefs about clinical effectiveness. This article evaluates the scientific validity of current drug terms and possible alternative classifications. Methods A historical, conceptual, and empirical review of the psychopharmacology literature is provided. Consistency of classification is examined by 3 major categories: chemical structure, pharmacodynamic mechanism, and clinical efficacy. Results Current drug terms based on clinical effectiveness are not valid scientifically, either claiming efficacy which is disproven or ignoring other areas of clinical efficacy. Hence, clinical efficacy is not a consistent and scientifically valid way of classifying psychotropic drugs. Chemical structures are also heterogeneous for drugs with similar clinical efficacy. The most consistent way to define drug classes is pharmacodynamic mechanism. Specific drug groups identified are: monoamine agonists ("antidepressants" and "stimulants"), dopamine blockers ("antipsychotics"), second messenger modifiers ("mood stabilizers), and gabaergic agonists ("anxiolytics" or "hypnotics"). Conclusions Consistent with a recent proposal of psychopharmacology organizations, this article proposes a new nomenclature based mainly on biological pharmacodynamic mechanisms. Specific terms that are scientifically valid and clinically practical are suggested. It is hoped that this new language would allow for more meaningful and accurate communication between clinicians and patients.
Post-Little Ice Age record of coarse and fine clastic sedimentation in an Alaskan proglacial lake

Many assessments of glacial sediment yield rely solely on mea- surements of fine-grained suspended sediment. We show that sus- pended sediment contributes ,20% of the total clastic sediment discharge into Iceberg Lake, an Alaskan proglacial lake. Drainage of this lake in 1999 exposed outcrops of varved lacustrine sediment that record suspended sediment deposition. Since a Little Ice Age highstand two centuries ago, lake level has dropped in four abrupt spillway-controlled events that are recorded stratigraphically as transient increases in the basinwide deposition of unusually fine grained sediments. Varve counting constrains ages of these events and, hence, of each abandoned shoreline and associated delta. Vol- umes of deltaic and lake-floor sediments constrain specific yields from four multidecadal intervals between A.D. 1825 and 1999. To- tal yield ranges from 3.8 to 4.9 3 10 3 t·km 22 ·yr 21 , and most of the sediment (81%-86%) is sand and gravel now in the deltas. A range of evidence suggests that sediment yield faithfully records up- stream sediment production in this small (66 km 2 ) and heavily gla- cierized basin, implying an effective subglacial erosion rate of 1.6 mm/yr. These data show that estimates of total yield based upon suspended sediment alone are subject to large errors and suggest that quarrying accounts for a large fraction of the glacial erosion in this system.
JOVIAN ICY MOON EXCURSIONS: Radiation Fields, Microbial Survival and Bio-contamination Study

The effects of both the cosmic ray heavy ion exposures and the intense trapped electron exposures are examined with respect to impact on cellular system survival on exterior spacecraft surfaces as well as at interior (shielded) locations for a sample mission to Jupiter's moons. Radiation transport through shield materials and subsequent exposures are calculated with the established Langley heavy ion and electron deterministic codes. In addition to assessing fractional DNA single and double strand breaks, a variety of cell types are examined that have greatly differing radio-sensitivities. Finally, implications as to shield requirements for controlled biological experiments are discussed.
Seasonal variation of serum concentrations of beta-carotene and alpha-tocopherol.

We studied the seasonal variation in serum concentrations of�3-carotene and a-tocopherol (HPLC) in 17 247 Finnish men who smoked. Month ofblood sampling was a sta- tistically significant determinant of serum concentration of 13- carotene in a regression model including age, body mass index, alcohol and fat intakes, total serum cholesterol, and daily cig- arettes as covariates. The serum concentrations were lowest in April-June and highest in October-November. The I.5-fold in- crease in the serum concentration of 13-carotene during the fall reflects the seasonality of dietary sources of carotenoids in Finland. The serum concentrations of a-tocopherol demon- strated no seasonal variation but remained close to 27.6 �zmol/ L throughout the year. The results indicate that the seasonal variation ofserum concentrations off3-carotene should be taken into account in long-term studies in which comparison of groups or individuals is based on serum concentrations. Am J C/in Nuir 1993:57:551-6.
Inclusive electron scattering from 2H,3He, and 4He.

We present new results for inclusive electron scattering in /sup 2/H, /sup 3/He, and /sup 4/He in order to test the reaction mechanism for quasielastic scattering as a function of nuclear density. Radiative corrections are applied to the cross section data and Rosenbluth separations are made for three-momentum transfer (q) between 300 and 600 MeV/c. The A and q dependencies of the data are discussed for the quasielastic peak and the region between the quasielastic peak and the ..delta.. resonance peak (dip region). Comparisons are shown between the data and models based on a quasielastic reaction mechanism. The models give a reasonable representation of the peak at qapprox.500 MeV/c, but the longitudinal data for the helium isotopes are significantly suppressed with respect to the quasielastic predictions at q<400 MeV/c. None of the calculations predict the rapid rise with q and A in the transverse strength in the dip region seen in the data. A significant breakdown of the quasielastic picture is seen in the data as A increases from 2 to 4.
Carcinoma of the Prostate

One of the most vital problems confronting the urological surgeon today concerns the early recognition and treatment of cancer of the prostate. Some authors have likened this lesion to a somewhat analogous one occurring in the female breast. In many points they are similar; in many others they are entirely different. Both are essentially diseases of the latter part of middle life. They are similar, also, in their tendency to spread very early by the way of the lymphatic system, in their power to disseminate far and wide, and in their predilection to skeletal metastasis. In neither of these two types of carcinoma is the prognosis as to the duration of life good, and in both the end-results of treatment are still unsatisfactory. Of the two, carcinoma of the prostate appears the more unfavorable. Oertel (1) points out the similarity in the reaction of breast and prostatic tissues and contends that carcinoid hyperplasia in each of these organs is potentially cancerous, although it does not always develop into cancer. Cheatle (2) calls attention to a sequence of events occurring in the prostate similar to that which is observed in certain diseases of the breast. The cystiphorous desquamative epithelial hyperplasia is transformed into epithelial neoplasia, and this latter condition further changes into true cancerous tissue. In one section of a prostate the author observed all of these three stages.
Identification and Prevention of Particulates in a Parenteral Solution of a Protein Kinase B Inhibitor

The aim of this work was to identify the root cause of particulates in a parenteral solution formulation of a protein kinase B inhibitor (AKT inhibitor) and to devise a formulation fix. While standard potency/purity analyses did not reveal degradation, it was determined that the mass of the particulates corresponds to that of a "dimer-like" degradation product. The dimer-like molecule manifested itself as particulates rather than impurities in standard HPLC analysis. Particulate formation was found to be pH dependent. Consequently, an optimum formulation pH at which the compound has adequate solubility and the rate of particulate formation is slow was identified.
Modeling of Future Cyber–Physical Energy Systems for Distributed Sensing and Control

This paper proposes modeling the rapidly evolving energy systems as cyber-based physical systems. It introduces a novel cyber-based dynamical model whose mathematical description depends on the cyber technologies supporting the physical system. This paper discusses how such a model can be used to ensure full observability through a cooperative information exchange among its components; this is achieved without requiring local observability of the system components. This paper also shows how this cyber-physical model is used to develop interactive protocols between the controllers embedded within the system layers and the network operator. Our approach leads to a synergistic framework for model-based sensing and control of future energy systems. The newly introduced cyber-physical model has network structure-preserving properties that are key to effective distributed decision making. The aggregate load modeling that we develop using data mining techniques and novel sensing technologies facilitates operations of complex electric power systems.
Mechanical Stress Changes the Movements and Organization of Biofilm-Associated Bacteria

Historically, studies analyzing collective movements, biofilm formation, and the emergence of pathogenicity in bacteria have focused on chemical signals that elicit changes in cell behavior, while responses to physical cues have only recently begun to garner attention. In contrast, the effects of changes in mechanical properties of the environment on eukaryotic cells have been studied extensively. It is known, for instance, that substrate stiffness can guide the migration of epithelial and endothelial cells and has profound effects on cell shape and division. Our research aims to examine how bacteria and bacterial colonies respond to changes in the physical properties of their environment (mechanical stress, stiffness, and surface topography) and to understand the molecular mechanisms behind the response. Previous work showed that the Gram-negative, biofilm-forming bacterium Myxococcus xanthus responds to tension and compression of its substrate's surface by forming elliptical colonies that expand most rapidly perpendicular to the axis of compression. This behavior, dubbed “elasticotaxis”, was initially hypothesized to be important for locating food sources. By combining physics-based modelling of the stresses in compressed substrates with experimental data showing the corresponding change in shape of M. xanthus colonies, we have established a linear correlation between the mechanical stress in the substrate and the degree of the elasticotaxis response. To identify the physical changes in the substrate that elicit the elasticotaxis response, we are investigating whether compression of the agar substrate leads to changes in topography, such as wrinkling, or to changes in material properties, such as polymer alignment. Recently, we found that elasticotaxis is not unique to M. xanthus; our preliminary results suggest many bacteria exhibit this behavior. Accordingly, we are examining whether elasticotaxis is common to both gliding bacteria and swarming bacteria and how it may affect biofilm formation.
Effect of Elevated Corticosterone Levels on Serum Gamma Globulin Concentrations in Newborn Rats

SummaryAdministration of 0.1 USP U ACTH to 9-day-old rats followed by similar treatments twice daily through Day 24 produced elevated serum corticosterone levels compared with saline-injected control values 1 hr after the last injection at 15, 18, 21, and 24 days of age. The concentration of serum gamma globulin was significantly lower in the ACTH-treated rats than in saline controls at 15, 18, 21, and 24 days postpartum, possibly due to premature termination of intestinal absorption of gamma globulin in the ACTH-treated group. The serum gamma globulin concentration increased in control rats between days 9 and 18, then declined between Days 21 and 24, while in the ACTH-treated rats, the level did not increase significantly between Days 9 and 15, and fell between 15 and 21 days of age. This experiment indicates that elevated concentrations of corticosterone, the primary glucocorticoid in rats, reduce the serum gamma globulin level during the neonatal period.