cssi/SciSciGPT-SciSciNet huggingface dataset:
Reactive properties of trans‐dichlorooxirane in relation to the contrasting carcinogenicities of vinyl chloride and trans‐dichloroethylen

Our objective in this work is to gain insight into the contrasting carcinogenic activities of vinyl chloride (definitely carcinogenic) and trans-dichloroethylene (apparently inactive). The initial metabolic step for each molecule is believed to be epoxidation of the double bond, and there is evidence indicating that for vinyl chloride, this epoxide (chlorooxirane) is its ultimate (direct-acting) carcinogenic form. This article presents the findings of a computational study of the reactive properties of trans-dichlorooxirane (the epoxide of trans-dichloroethylene). An ab initioSCF-MO procedure was used to determine the energy requirements for stretching the CO and CCl bonds (SN1 reactivity) and to study the epoxide's SN2 interactions with ammonia, taken as a model nucleophile. The starting points were the oxygen- and chlorine-protonated forms of the epoxide. The structure of the system was reoptimized at each step along the various reaction pathways. The results of this work are compared to an analogous earlier study of the reactive properties of chlorooxirane. The chlorineprotonated CCl bonds are found to have much lower energy barriers to stretching than do the oxygen-protonated CO bonds. In the SN2 processes, intermediate complexes are formed with ammonia by both the oxygen- and the chlorine-protonated epoxides; the latter complexes are the more stable. Based on our results, we propose two mechanisms (one SN1 and the other SN2) whereby trans-dichlorooxirane can interact with N7 of guanine to produce an adduct analogous to one formed by chlorooxirane, which has been found to be the primary in vivoDNA alkylation product of vinyl chloride and to which has been attributed the carcinogenicity of the latter. Overall, trans-dichlorooxirane is found to be chemically more reactive than chlorooxirane; this may help to account for the much lesser carcinogenic and mutagenic activities of trans-dichloroethylene, since the epoxide may be reacting with other cellular nucleophiles before it reaches the key site(s) at which the carcinogenic or mutagenic interaction would occur. We also offer some speculations concerning other possible factors related to the differing carcinogenicities of vinyl chloride and trans-dichloroethylene, such as ease of epoxide formation and the likelihood of oxygen protonation.
Logic Performance of 40 nm InAs HEMTs

We have experimentally evaluated the logic performance of 40 nm InAs HEMTs. For a barrier thickness of 4 nm, we find that 40 nm InAs HEMTs exhibit excellent logic figures of merit and scalability at VDS = 0.5 V, such as DIBL = 80 mV/V, S = 70 mV/dec, and fT = 475 GHz. These remarkable results arise from the combination of the outstanding transport properties of InAs channel, and the use of a thin insulator and a thin channel. In addition, these devices exhibit ION/IOFF ratios in excess of 104, revealing that band-to-band tunneling is not a significant concern in our device design. Our InAs HEMTs exhibit an injection velocity at the virtual source point that is a factor of 1.6X higher than state-of-the-art Si n-MOSFETs, in spite of the significantly lower supply voltage.
Response to ‘Etiology-based classification of hemolytic uremic syndrome/thrombocytopenic purpura. What about hemolytic uremic syndrome associated with urinary tract infections?’

Members of the European Paediatric Study Group1 for hemolytic uremic syndrome are aware of cases of hemolytic uremic syndrome in which verocytotoxin (shiga-like toxin)-producing Escherichia coli infects the urinary tract and apparently not the intestine. In these cases, the etiology seems reasonably advanced and it would be appropriate for them to be classified in our proposal under Part 1, 'Ia, Shiga and verocytotoxin (shiga-like toxin)-producing bacteria'. The fact that we did not mention the phenomenon of primary verocytotoxin (shiga-like toxin)-producing E.coli urinary infection reflects both the shortage of space in a review article and the rarity of the occurrence. In the investigative guideline that we referred, http://espn.uwcm.ac.uk/guidelines.htm we point out that a causative verocytotoxin (shiga-like toxin)-producing E.coli infection may not induce diarrhea. We assume that evidence of urinary infection is sought routinely in all cases of acute renal failure and agree that if E.coli or possibly other Gram-negative organisms are identified in a patient with hemolytic uremic syndrome, they should be investigated for the ability to produce verocytotoxins.
Time-Averaged Active Controller for Turbofan Engine Fan Noise Reduction

An active control system has been developed and used experimentally on an operational turbofan engine to reduce inlet tonal noise at the fan blade passage frequency. Both single channel and multichannel systems were tested. The control approach used is the feedforward derivative measurement time-averaged adaptive algorithm. This algorithm is capable of adapting to a nonstationary system, requiring no prior knowledge of the system. A reference sensor mounted in the casing of the fan provides the fan blade passing frequency reference signal to the controller. Microphones with a large sensing area are placed in the acoustic far field of the engine. The control algorithms minimize a cost function, the sum of the error signal mean-square-values, by activating loudspeakers that are mounted around the inlet of the engine. The control signals are obtained by filtering the reference signal with finite impulse response digital filters. The control algorithm finds the optimum filter weights by using statistical estimates of the cost function to be minimized. A single channel control system was tested on an axisymmetric dominant mode case and produced reductions of up to 17 dB at the error microphone. The controller maintained reductions in the fan tone even as the engine speed was increased. In a traverse of the radiated sound field of the engine the fan blade passage tone was reduced over a sector of 30 deg around the error sensor with a considerable spillover increase in the fan tone outside of this sector. Two six-channel control systems were developed and tested on both axisymmetric and spinning mode dominant cases. Reductions of up to 19.7 dB were achieved over large sectors around the error microphones with significantly reduced spillover.
Application of multiple time series analysis to the estimation of pneumonia and influenza mortality by age 1962–1983

We employed multiple time series analysis to estimate the impact of influenza on mortality in different age groups, using a procedure for updating estimates as current data become available from national mortality data collected from 1962 to 1983. We compared mortality estimates that resulted from a multivariate model for epidemic forecasting with those obtained from univariate models. We found more accurate prediction of deaths from all age groups using the multivariate model. While the univariate models show an adequate fit to the data, the multivariate model often enables earlier detection of epidemics. Additionally, the multivariate approach provides insight into relationships among different age groups at different points in time. For both models, the largest excess mortality due to pneumonia and influenza during influenza epidemics occurred among those 65 years of age and older. Although multiple time series models appear useful in epidemiologic analysis, the complexity of the modelling process may limit routine application.
CHANGES OF APPARENT IONIC MOBILITIES IN PROTOPLASM : III. SOME EFFECTS OF GUAIACOL ON HALICYSTIS

Lowering the pH of sea water from 8.2 to 6.4 lowers the positive P.D. of Halicystis reversibly (this does not happen with Valonia). Exposure to sea water at pH 6.4 does not affect the apparent mobility of Na(+) or of K(+) (this agrees with Valonia). Guaiacol makes the P.D. of Halicystis less positive (in Valonia it has the opposite effect). Exposure to guaiacol does not reverse the effect of KCl in Halicystis which in this respect differs from Valonia. The P.D. can be changed from 66 mv. positive to 23 mv. negative by the combined action of KCl and guaiacol. Exposure to guaiacol affects Halicystis and Valonia similarly in respect to their behavior with dilute sea water. Normally the dilute sea water makes the P.D. more negative but after sufficient exposure to guaiacol dilute sea water either produces no change in P.D. or makes it more positive. In the latter case we may assume that the apparent mobility of Na(+) has become greater than that of Cl(-) as the result of the action of guaiacol. (Normally the apparent mobility of Cl(-) is greater than that of Na(+).) In Halicystis, as in Valonia and in Nitella, an organic substance can greatly change the apparent mobilities of certain inorganic ions (K(+) or Na(+)).
The planet Mars as seen at the end of the Viking Mission

The paper presents a summary of new knowledge about Mars obtained from Mariner and Viking missions. Specific subjects include Martian geologic features, composition of the surface, the atmosphere, and the polar caps, and Martian meteorology, including temperatures, pressures, tides, dust storms, and atmospheric water vapor. The program of further Mars exploration is outlined. The major element of the program will be a sample return mission, utilizing orbiters and limited-range rovers with enough instrumentation to identify, acquire, and return well documented samples from two or more sites.
Dhatri - A Pervasive Cloud initiative for primary healthcare services

This paper introduces the concept entitled ‘Pervasive Cloud’ which is meant for ‘Accessing the Power of a Cloud through Pervasive Access of Mobile Communications’. ‘Dhatri’ is a Pervasive Cloud Based Healthcare Application targeted towards Healthcare needs specifically for Rural and Deep Rural Areas. Dhatri ‘inherits’ the powerful features of a typical Cloud Computing and enables the Pervasive Healthcare Access.
9/11 And Its Effects on the Rates of Return and Risk in the Hospitality Industry: An Event Study Approach

ABSTRACT This study analyzes the impact of the terrorist attacks of September 11, 2001, on the rates of return on equity and risk within the hospitality sector. The Brown and Warner (1985) event study approach is used in the analysis. As such, the behavior of equity returns and risk of hospitality firms in the face of terrorism-related events are better understood.
Electoral Authoritarianism and Credible Signaling in International Crises

How, if at all, do nondemocratic elections affect credible signaling in international crises? While the literature on credible signaling emphasizes the importance of electoral competition, it does not specify the minimal conditions that elections must satisfy in order to enhance the credibility of threats. We address this oversight by focusing on two fundamental properties of electoral institutions: (1) the degree of proincumbent bias and (2) the vulnerability of the incumbent to a de facto loss of power following an opposition victory. Our theory argues that both decreases in electoral bias and increases in incumbent vulnerability introduce greater accountability into the electoral process and thus enhance the credibility of public threats, even when elections fail to meet basic democratic standards. We apply these insights to the case of electoral authoritarianism, that is, regimes in which some form of electoral competition exists but basic principles of democratic governance are commonly violated. Usi...
Chronic kidney disease is associated with adverse outcomes among elderly patients taking clopidogrel after hospitalization for acute coronary syndrome

Chronic kidney disease (CKD) is associated with worse outcomes among patients with acute coronary syndrome (ACS). Less is known about the impact of CKD on longitudinal outcomes among clopidogrel treated patients following ACS. Using a retrospective cohort design, we identified patients hospitalized with ACS between 10/1/2005 and 1/10/10 at Department of Veterans Affairs (VA) facilities and who were discharged on clopidogrel. Using outpatient serum creatinine values, estimated glomerular filtration rate [eGFR (1.73 ml/min/m2)] was calculated using the CKD-EPI equation. The association between eGFR and mortality, hospitalization for acute myocardial infarction (AMI), and major bleeding were examined using Cox proportional hazards models. Among 7413 patients hospitalized with ACS and discharged taking clopidogrel, 34.5% had eGFR 30–60 and 11.6% had eGFR =60, individuals with eGFR 30–60 (HR 1.45; 95% CI: 1.18-1.76) and = 60. Lower levels of kidney function were associated with higher rates of death, AMI hospitalization, and major bleeding among patients taking clopidogrel after hospitalization for ACS.
Pravastatin Increases Survival and Inhibits Natural Killer Cell Enhancement Factor in Liver Transplanted Rats

Pravastatin, a 3-hydroxy-3-methylglutaryl coenzyme A reductase inhibitor, has been shown to decrease the number of acute rejection episodes in cardiac and renal transplant patients. This study evaluates the effects of pravastatin on survival of rats following liver transplant and attempts to elucidate the mechanisms of these effects. Both survival and natural killer cell enhancing factor (NKEF) studies utilized Dark Agouti rats for donor livers transplanted into Brown Norway rats as recipients. All rats received daily low-dose cyclosporine (CsA) 2 mg/kg/day by gavage. The treated groups also received gavage doses of pravastatin, 20 mg/kg/day. Survival data were analyzed by the method of Kaplan-Meier and log-rank chi 2 tests for statistical significance. For NKEF evaluation, rats were sacrificed at varying time points; total RNA was extracted from the liver and hybridized with 32P-radiolabeled NKEF DNA probes in the Northern blot technique. Radiographs were quantitated using densitometry. Data were analyzed by two-way ANOVA. Actuarial survival was improved (P < < 0.05) in rats treated with pravastatin in addition to low-dose CsA (n = 41, CsA alone n = 74). Less fibrosis and chronic rejection was seen on histological section in the treated animal livers, P < 0.05, NKEF was seen maximally at Days 5-15 tapering off at Day 21. NKEF-a and NKEF-b levels were significantly decreased in the animals treated with CsA and pravastatin compared to CsA alone in the group of animals < 16 days postop (P < < 0.05). Pravastatin improves survival in rats following OLT and while the mechanism is still unknown, inhibition of natural killer cell enhancement factor may represent an alteration in the overall immune response.
Neurochemical neutralization of methamphetamine with high-affinity nonselective inhibitors of biogenic amine transporters: a pharmacological strategy for treating stimulant abuse.

The abuse of methamphetamine (METH) and other amphetamine-like stimulants is a growing problem in the United States. METH is a substrate for the 12-transmembrane proteins which function as transporters for the biogenic amines dopamine (DA), serotonin (5-HT), and norepinephrine (NE). Increased release of CNS DA is thought to mediate the addictive effects of METH, whereas increased release of NE in both the peripheral and CNS is thought to mediate its cardiovascular effects. The neurotoxic effects of METH on both dopaminergic and serotonergic nerves requires the transport of METH into the nerve terminals. Thus, transport of METH into nerve terminals is the crucial first step in the production of METH-associated pharmacological and toxicological effects. A single molecular entity which would block the transport of METH at all three biogenic amine transporters might function to neurochemically neutralize METH. This agent would ideally be a high-affinity slowly dissociating agent at all three transporters, and also be amenable to formulation as a long-acting depot medication, such as has been accomplished with an analog of GBR12909. As a first step towards developing such an agent, we established an in vitro assay which selectively detects transporter substrates and used this assay to profile the ability of a lead compound, indatraline, to block the releasing effects of METH and MDMA at the DA, 5-HT, and NE transporters. The major finding reported here is that indatraline blocks the ability of METH and MDMA to release these neurotransmitters. Synapse 35:222-
Optimal dynamic interval management in external memory

The authors present a space- and I/O-optimal external-memory data structure for answering stabbing queries on a set of dynamically maintained intervals. The data structure settles an open problem in databases and I/O algorithms by providing the first optimal external-memory solution to the dynamic interval management problem, which is a special case of 2-dimensional range searching and a central problem for object-oriented and temporal databases and for constraint logic programming. The data structure simultaneously uses optimal linear space (that is, O(N/B) blocks of disk space) and achieves the optimal O(log/sub B/ N+T/B) I/O query bound and O(log/sub B/ N) I/O update bound, where B is the I/O block size and T the number of elements in the answer to a query. The structure is also the first optimal external data structure for a 2-dimensional range searching problem that has worst-case as opposed to amortized update bounds. Part of the data structure uses a novel balancing technique for efficient worst-case manipulation of balanced trees, which is of independent interest.
The relativity of positive deviance: The case of the French Impressionists

Labeling theory has traditionally been applied to negative deviance; nevertheless, this paper addresses the relationship of labeling theory to positive deviance. As is the case with negative deviance, actions or behaviors that are defined as positive deviance vary over time, across societies, and within societies. Positive deviants can become negative deviants and negative deviants can become positive deviants. To substantiate this process, the labeling of the French Impressionists is presented. The French Impressionists were collectively designated to be negative deviants and then later elevated to a positive deviant status. Consequently, labeling theory can be applied to elucidate the nature of positive deviance. Positive deviance and negative deviance are similar.
Group choreography: mechanisms orchestrating the collective movement of border cells

Cell movements are essential for animal development and homeostasis but also contribute to disease. Moving cells typically extend protrusions towards a chemoattractant, adhere to the substrate, contract and detach at the rear. It is less clear how cells that migrate in interconnected groups in vivo coordinate their behaviour and navigate through natural environments. The border cells of the Drosophila melanogaster ovary have emerged as an excellent model for the study of collective cell movement, aided by innovative genetic, live imaging, and photomanipulation techniques. Here we provide an overview of the molecular choreography of border cells and its more general implications.
VEGF Drives Cancer-Initiating Stem Cells Through VEGFR-2/Stat3 Signaling to Upregulate Myc and Sox2

Vascular endothelial growth factor-A (VEGF), a potent angiogenic factor, is also implicated in self-renewal in several normal tissue types. VEGF has been shown to drive malignant stem cells but mechanisms thereof and tumor types affected are not fully characterized. Here, we show VEGF promotes breast and lung cancer stem cell (CSC) self-renewal via VEGF receptor-2 (VEGFR-2)/STAT3-mediated upregulation of Myc and Sox2. VEGF increased tumor spheres and aldehyde dehydrogenase activity, both proxies for stem cell function in vitro, in triple-negative breast cancer (TNBC) lines and dissociated primary cancers, and in lung cancer lines. VEGF exposure before injection increased breast cancer-initiating cell abundance in vivo yielding increased orthotopic tumors, and increased metastasis from orthotopic primaries and following tail vein injection without further VEGF treatment. VEGF rapidly stimulated VEGFR-2/JAK2/STAT3 binding and activated STAT3 to bind MYC and SOX2 promoters and induce their expression. VEGFR-2 knockdown or inhibition abrogated VEGF-mediated STAT3 activation, MYC and SOX2 induction and sphere formation. Notably, knockdown of either STAT3, MYC or SOX2 impaired VEGF-upregulation of pSTAT3, MYC and SOX2 expression and sphere formation. Each transcription factor, once upregulated, appears to promote sustained activation of the others, creating a feed-forward loop to drive self-renewal. Thus, in addition to angiogenic effects, VEGF promotes tumor-initiating cell self-renewal through VEGFR-2/STAT3 signaling. Analysis of primary breast and lung cancers (>1300 each) showed high VEGF expression, was prognostic of poor outcome and strongly associated with STAT3 and MYC expression, supporting the link between VEGF and CSC self-renewal. High-VEGF tumors may be most likely to escape anti-angiogenics by upregulating VEGF, driving CSC self-renewal to re-populate post-treatment. Our work highlights the need to better define VEGF-driven cancer subsets and supports further investigation of combined therapeutic blockade of VEGF or VEGFR-2 and JAK2/STAT3.
Relaxed Selection Among Duplicate Floral Regulatory Genes in Lamiales

Polyploidization is a prevalent mode of genome diversification within plants. Most gene duplicates arising from polyploidization (paralogs) are typically lost, although a subset may be maintained under selection due to dosage, partitioning of gene function, or acquisition of novel functions. Because they experience selection in the presence of other duplicate loci across the genome, interactions among genes may also play a significant role in the maintenance of paralogs resulting from polyploidization. Previously, we identified duplicates of the genes LFY/FLO and AP3/DEF that directly interact in a floral regulatory pathway and are thought to be the result of ancient polyploidization in the Lamiales (> 50 mya). Although duplicates of MADS box genes including AP3/DEF are common throughout the angiosperm lineage, LFY/FLO duplicates in Lamiales are the first reported outside of tetraploid taxa. In order to explore hypotheses for the joint preservation of these interacting floral regulatory genes including novel LFY/FLO paralogs, here we clone FLO and DEF duplicates from additional Lamiales taxa and apply codon substitution models to test how selection acts on both genes following duplication. We find acceleration in the ratio of nonsynonymous-to-synonymous nucleotide substitutions for one (FLO) or both (DEF) paralogs that appears to be due to relaxed purifying selection as opposed to positive selection and shows a different pattern among functional domains of these genes. Several mechanisms are discussed that might be responsible for preservation of co-orthologs of FLO and DEF in Lamiales, including interactions among the genes of this regulatory pathway.
An analysis of the potential impact of computed tomographic colonography (virtual colonoscopy) on colonoscopy demand.

Background & Aims: There has been much speculation about the potential impact on the use of conventional colonoscopy if "virtual" computed tomographic colonography (CTC) became a widely accepted modality for colorectal cancer (CRC) screening. However, no formal analysis of the impact of CTC on colonoscopy demand has been reported. Methods: A mathematical model to predict colonoscopy demand based on several relevant input parameters was constructed. Current national colonoscopy practice, estimated using various published reports, was used as the foundation to project colonoscopy demand if CTC were implemented as the primary CRC screening modality. Results: In the base-case analysis, if CTC were used as the primary modality for CRC screening, 1.78 million colonoscopies could be eliminated from the total 6.47 million in 2003. Depending on the polyp size threshold used to define a CTC study as positive (6 or 10 mm), this loss would be partially offset by 1.21 million (6 mm) or .34 million (10 mm) follow-up colonoscopies for CTC examinations with positive findings, resulting in a net loss of .57 million (8.8% decrease) (6 mm) or 1.44 million (22.3% decrease) (10 mm). Extensive sensitivity analyses showed that the findings of this model were robust and insensitive to most parameters tested but were sensitive to a few parameters, including the percentage of CTC examinations with positive findings. Conclusions: Wide-scale implementation of CTC for CRC screening would likely lead to a decrease in use of conventional colonoscopy. The percentage of CTC studies with positive findings seemed to be a pivotal variable, which would be determined in large part by the polyp size ultimately established to define a positive finding.
Against underdetermined reflexive binding

Reflexive binding has for a decade now been a fruitful area of inquiry for researchers seeking to establish that adult second language (L2) learners have access to Universal Grammar (UG), in this c...
Flat Affect in Schizophrenia: A Test of Neuropsychological Models

This study evaluated the association between neuropsychological indices of frontal lobe and right hemisphere impairment and deficits in the expression of affect in schizophrenia. The advantages of the present study were that unmedicated schizophrenia patients were studied and relevant demographic characteristics were controlled. Furthermore, deficits in affective expression were assessed both in a clinical interview and in subjects' response to affect-eliciting films. Despite the fact that schizophrenia subjects demonstrated significantly higher clinical ratings of affective flattening and less facial expression while viewing films than demographically matched control subjects, neuropsychological performance was not consistently related to these expressive deficits. The results thus failed to support for the proposed neuropsychological models of affective deficits in schizophrenia. The characterization of flat affect as a purely emotional deficit is questioned, and limitations of current neuropsychological theories of emotional expression and neuropsychological methods to test these theories in the study of schizophrenia are discussed as relevant concerns for future research.
Early Life Manganese Exposure Upregulates Tumor-Associated Genes in the Hypothalamus of Female Rats: Relationship to Manganese-Induced Precocious Puberty

Prepubertal exposure to low, but elevated levels of manganese (Mn) can induce increased secretions of puberty-related hormones resulting in precocious pubertal development in female rats. These events are due to an action of the element within the hypothalamus to induce the secretion of gonadotropin-releasing hormone (GnRH). Because of these prepubertal effects of Mn and because precocious puberty is a serious neuroendocrine disorder, we have assessed whether early life exposure to this environmental element is capable of precociously upregulating the expression of a select group of genes previously associated with tumor growth or suppression, and that have more recently been shown to increase at the normal time of puberty. Female rat pups received a daily dose of either 10mg/kg manganese(II) chloride or an equal volume of saline by gastric gavage from postnatal day 12 through day 22 or 29. At this time, blood was collected for estradiol analysis and hypothalamic brain tissue frozen on dry ice until assessed for gene expressions. Rats exposed to the elevated levels of Mn showed a precocious increase in GnRH gene expression in the preoptic area and rostral hypothalamus on day 29, an action associated with precociously increased expressions of specific tumor-associated, puberty-related genes. These results demonstrate for the first time that prepubertal Mn exposure is capable of activating specific upstream genes regulating hypothalamic GnRH and suggest that these actions are involved in the mechanism by which this element can induce precocious puberty.
A Unified Framework for Layered Transmission Over Fading and Packet Erasure Channels

We consider layered transmission of a successively refinable source over a quasi-static fading channel. We establish a duality relationship between this problem and that of packet transmission over erasure channels and use it to share solution techniques in both domains. For a Gaussian source and the fading channel, a low-complexity, optimal algorithm is proposed, and it is shown that the corresponding dual for packet erasure channels has a linear complexity as opposed to the quadratic complexity of the best known optimal algorithms in the literature. For non-Gaussian sources, the optimal rate allocation problem for fading channels is solved using the dual solution for erasure channels. It is also shown that a single-layer system is optimal for fading channels if the goal is to maximize the rate. Numerical results for multiple antenna Rayleigh fading channels are presented for Gaussian sources and practical image coders. It is shown that a few number of layers significantly improves the performance. Finally, we numerically show that for practical operating conditions, optimizing the asymptotic measure of distortion exponent is not enough when there are more than one transmit or receive antennas.
Pass the Butter

The Hedgehog family of signaling molecules is essential for a variety of developmental processes. In this issue, Porter et al . ([p. 255][1]) identify the lipid adduct to Sonic hedgehog —necessary for its function in vertebrate head development—as cholesterol. In his Perspective, Martin discusses how this new function for cholesterol may be the first example of a modification used by many signaling molecules. [1]: /lookup/doi/10.1126/science.274.5285.255
Rapid Evolutionary Change and the Coexistence of Species

Understanding the forces that allow multiple species to coexist remains a central focus of community ecology. Building evidence that evolutionary changes frequently occur on timescales relevant for ecological dynamics suggests that a complete understanding of the maintenance of diversity is likely to require incorporation of evolutionary dynamics. Coexistence mechanisms can be classified into two groups on the basis of whether they reduce inherent differences in species performance (equalizing effects) or buffer against extinction by providing advantages to rare species (stabilizing effects). Theoretical and empirical evidence suggests that rapid evolution can increase equalizing and/or stabilizing effects in several ways. Directional evolutionary changes can result in new ecological conditions that are more equal or stable than the initial state. Additionally, coevolution between competitors or consumers can lead to cyclic dynamics that provide novel evolutionary equalizing or stabilizing effects.
A computational model of membrane lipid electronic properties in relation to neural signaling.

We present a computational model of a transiently-organized neural membrane molecular system with possible information-processing capacity. The model examines field-induced dipole and quadrupole moments and polarizability in monomeric, dimeric, and trimeric ethenes. Polarization of the ethenes is strongly indicated. This result is interpreted as a significant electronic feature of a molecular computing system based on organization of membrane lipids into a transient (10 4 s) crystalline state due to lipid-protein hydrophobic mismatch at the membrane-ionchannel interface. Predictive implications of the model’s electronic features are briefly discussed. © 2001 Elsevier
Surgical Management of Pancreatic Neuroendocrine Tumors

Pancreatic neuroendocrine tumors (PNETs) are uncommon tumors with a range of clinical behavior. Some PNETs are associated with symptoms of hormone secretion, with increased systemic levels of insulin, gastrin, glucagon, or other hormones. More commonly, PNETs are nonfunctional, without hormone secretion. Surgical resection is the mainstay of therapy, particularly for localized disease. Surgical therapy must be tailored to tumor and clinical characteristics. Resection may be particularly indicated in the setting of hormone hypersecretion. Small, incidental PNETs are increasingly managed nonoperatively. Surgery may also be indicated in some instances of metastatic disease, if all metastatic foci may be removed.
Development of a low-cost fast-timing microchannel plate photodetector

Abstract We report on the design, fabrication and characterization of a prototype 6 × 6 cm 2 microchannel plate photodetector with precise fast-timing measurement capability. The whole assembly is made of low cost glass materials with a bialkali photocathode top window. All components are hermetically sealed in vacuum. The prototype photodetector exhibits time resolution of 65 ps and 16 ps at single-photoelectron and multi-photoelectron levels, respectively. The spatial resolution reaches 0.54 mm for multi-photoelectron measurements. The bialkali photocathode exhibits a maximum quantum efficiency exceeding 20% with a uniformity of ± 40 % .
The effect of liquid smoke on Listeria monocytogenes

Although no documented outbreaks of listeriosis have been associated with the consumption of meat in the United States, Listeria monocytogenes is common to the environment of processing plants. In an effort to control the potential hazard of surface contamination of beef franks with L. monocytogenes , five different Red Arrow smoke products were evaluated for their antimicrobial activity in 0.5% and 0.25% smoke preparations against L. monocytogenes LCDC 81-861, a serotype 4b strain. In smoke preparations of 0.5%, CharSol-10, Aro-Smoke P-50, and CharDex Hickory were effective in reducing viable cell numbers below detection within 4 h and CharSol PN-9 and CharOil Hickory gave similar results within 24 h. In smoke preparations of 0.25%, CharSol-10 and Aro-Smoke P-50 again demonstrated their strong antimicrobial effects within 4 h, but the activity of CharDex Hickory, CharSol PN-9, and CharOil Hickory are reduced at this concentration requiring 24, 48, and 96 h, respectively, to reduce microbial numbers below detection. Since CharSol-10 demonstrated strong antimicrobial effects against L. monocytogenes in pure culture, it was selected as the liquid smoke to be used as a full strength dip treatment for beef franks surface inoculated with 6 strains of L. monocytogenes then vacuum packaged and stored at 4±l°C for 72 h. In untreated beef franks, L. monocytogenes numbers remained unchanged after 72 h, while beef franks dipped in CharSol-10 liquid smoke exhibited a greater than 99.9% reduction in L. monocytogenes numbers after 72 h of storage.
Abstract 124: Quantifying Intracranial Aneurysm Wall Permeability for Risk Assessment Using Dynamic Contrast Enhanced MRI: A Pilot Study

Introduction: Aneurysmal subarachnoid hemorrhage is the leading cause of non-traumatic hemorrhagic strokes. We propose a technique for assessing intracranial aneurysm (IA) rupture risk by quantifying wall permeability with dynamic contrast enhanced (DCE) MRI. We determine the correlation between IA wall permeability and established metrics of rupture risk. Methods: Twenty aneurysms in 19 patients were imaged with DCE-MRI and wall permeability parameters (kTrans and vL) were quantified adjacent to the aneurysm wall using Tofts’ permeability model (Figure 1). The DCE time course (1a), the AIF (red), and observed signal, S(t) (white) are measured. The permeability signal, P(t) (c) is modeled and fitted using Toft’s equation allowing quantitation of kTrans (d), shown superimposed on the DCE image. Three risk paradigms based on size indices (size, aspect ratio) and clinical criteria (progression to rupture, symptomatic presentation, dome irregularities) were used to split aneurysms into high and low-risk groups. Mean kTrans and vL were calculated in each risk group for each paradigm and compared using a student’s t-test. In addition, correlation analysis was used to compare kTrans and vL against size and aspect ratio. Results: In all IAs, there was pronounced increase in wall permeability compared to a paired healthy normal vessel (kTrans - 0.0922 vs. 0.0096 min-1, p Conclusions: Increased wall-permeability in intracranial aneurysms correlates with rupture risk and may indicate instability, growth, or remodeling. Further studies with histological correlation on harvested IA wall specimens are necessary.
Relativity: The Special and the General Theory, 100th Anniversary Edition, by Albert Einstein: Scope: general interest, edited book. Level: general readership, non-specialists, pre-university, undergraduate, advanced undergraduate, postgraduate, early career researcher, researcher, teacher, specialist, scientist

Albert Einstein’s Annus Mirabilis of 1905 saw the completion of his landmark seminal papers on the photoelectric effect law, Brownian motion, Special Relativity and the Mass–Energy Equivalence Prin...
MAIL SURVEY RESPONSE BY SMOKING STATUS

A detailed smoking history questionnaire was mailed to a series of 1987 white male veterans participating in the Normative Aging Study of the Veterans' Administration Outpatient Clinic in Boston, Mass. Response time from mailing date to return date was determined and then compared by various smoker categories. Although a total response rate of 96 percent was achieved after six months, the results showed that cigarette smoker response rates were considerably lower than the other smoker categories withing 30 days and within 60 days of the original mailing date. Cigarette smokers would therefore be under-represented if the data collection had ended within these spans of time; and even to some extent after six months had elapsed from time of original mailing. A relationship was also found between amounts of cigaretts smoked and rate of response with heavier smokers being slowest to respound. The implications of the findings with respect to cohort studies of smoking and heath are discussed.
Magnetic Resonance Imaging: Advanced Applications in Breast Cancer

Breast MRI is a highly sensitive imaging tool for breast cancer detection. In general clinical practice, breast MRI utilizes a limited dynamic contrast-enhanced (DCE) acquisition that provides morphologic and semi-quantitative kinetic information to allow characterization of breast findings. This approach provides sensitivities approaching 100 % for breast cancer detection; however, its specificity remains moderate due to limited ability to differentiate benign pathologic processes that enhance from malignancies. Several advanced MRI techniques, such as high-temporal resolution DCE that allows robust quantitative pharmacokinetic analysis, diffusion-weighted imaging that allows microstructural characterization, and MR spectroscopy that reflects chemical composition, hold promise to improve standard breast MRI specificity and to serve as imaging biomarkers that can guide treatment decisions. In this review article, we review recent updates in advanced breast MRI applications, including their potential clinical uses and challenges to implementation.
Product Innovation in a Model of Settlements of Drug Patent Litigation

A generic drug maker that has been sued for infringing a patent on a branded drug will sometimes promise, as part of an agreement settling the litigation, to delay selling its drug until as late as the expiration of the patent term. I adapt the standard optimal patent term model to determine whether the delay in competition caused by such agreements raises consumer welfare by increasing rewards for innovation. Calibrating the model with U.S. drug market data, I find that, for all but the patents with the greatest probability of surviving litigation, settlements that delay entry by more than fifteen months harm consumers. I find that generic drug makers are in some cases willing to agree to enough delay to harm consumers, even in the absence of a reverse payment, and that harm can reach $1.3 billion for the average drug.
What's in a Name? Interlocutors Dynamically Update Expectations about Shared Names

In order to refer using a name, speakers must know that their addressee knows about the link between the name and the intended referent. In cases where speakers and addressees learned names together, speakers are adept at using names only when their addressee knows them. But speakers do not always share such learning experience with their conversational partners. In these situations, what information guides speakers’ choice of referring expression? A speaker who is uncertain about a names’ common ground (CG) status often uses a name and description together. This N+D form allows speakers to demonstrate knowledge of a name, and could provide, even in the absence of miscommunication, useful evidence to the addressee regarding the speaker’s knowledge. In cases where knowledge of one name is associated with knowledge of other names, could provide indirect evidence regarding knowledge of other names that could support generalizations used to update beliefs about CG. Using data explanation approaches to language processing as a guiding framework, we predict that interlocutors can use their partner’s choice of referring expression, in particular their use of an N+D form, to generate more accurate beliefs regarding their partner’s knowledge of other names. In Experiment 1, we find that domain experts are able to use their partner’s referring expression choices to generate more accurate estimates of CG. In Experiment 2, we find that interlocutors are able to infer from a partner’s use of an N+D form which other names that partner is likely to know or not know. Our results suggest that interlocutors can use the information conveyed in their partner’s choice of referring expression to make generalizations that contribute to more accurate beliefs about what is shared with their partner, and further, that models of CG for reference need to account not just for the status of referents, but the status of means of referring to those referents.
Genetic Variability for Mineral Element Concentrations of Wild Jerusalem Artichoke Forage

One of the potential uses of Jerusalem artichoke (Helianthus tuberosus L.) is as a forage crop. Information on inherent differences in forage nutritional quality is essential if the quality of the forage is to be improved through breeding. The objectives of this study were to determine the genotypic variability among and within wild Jerusalem artichoke populations for the concentration of N, P, Ca, Mg, K, and the Ca/P ratio in the forage at flowering, estimate the magnitude of genotype x environment interaction, and examine relationships among mineral concentrations in the forage. Nine wild Jerusalem artichoke populations grown in an irrigated field nursery at Bushland, TX, were evaluated for N, P, Ca, Mg, K, and the Ca/P ratio in the forage at flowering over a 2-yr period. Population, year x population, and error variances were estimated to calculate the phenotypic variance. Estimates of the within-population variances were also determined. The adequacy of Jerusalem artichoke forage at flowering for maintenance of a ruminant animal was classified as follows: N, Ca, Mg, and K as adequate, P inadequate, and the Ca/P ratio as excessive. There were genotypic differences among the nine populations for N, K, P, Ca, Mg, and the Ca/P ratio for both years and averaged across years. The magnitude of the genotypic variance components indicated that a substantial proportion of the total variation for these elements was due to genotype, indicating the possibility of improvement through hybridization and selection. Within-population variation for N, Ca, and K was high, indicating potential for improvement with further selection within populations. Population variances for P and Mg were low, suggesting it will be difficult to improve these with selection. Unfortunately, P is inadequate in the forage to begin with, and our data indicated that selecting within populations for high P may not be very successful.
Glycogen in Pupal and Adult Stable Flies as Affected by a Juvenile Hormone Analogue

The juvenile hormone analogue, ( E )-4-[(6,7-epoxy-3-ethyl-7-methyl-2-nonenyl)oxy]benzene, applied topically to pupae and adults of Stomoxys calcitrans (L.) interfered with the utilization of glycogen. The glycogen content of treated pupae remained high and declined gradually for 6 days; that of untreated pupae declined sharply the 1st 24 hours after pupation. Treated adults demonstrated delayed toxicity and had a glycogen level different from that of untreated adults.
An Archaeological Survey of Power Line Distribution Routes Near Uvalde and Blewett For Rio Grande Electric Cooperative, Inc., Uvalde and Kinney Counties, Texas

An archaeological survey was conducted of power line routes near Uvalde and Blewett in Uvalde and Kinney Counties, Texas, for the Rio Grande Electric Cooperative, Inc. Four prehistoric sites were found; however, only two sites (41 KY 22 and 41 KY 24) are recommended for testing to determine eligibility for nomination to the National Register of Historic Places. The survey was conducted during January 1983, in accordance with the National Historic Preservation Act of 1966, as amended, and Executive Order 11593.
Surgical site infection rates in laparoscopic versus open colorectal surgery.

The purpose of this study was to use the American College of Surgeons National Surgical Quality Improvement Program (ACS-NSQIP) database to evaluate the incidence of postoperative surgical site inf...
Sex-Based Disparities in Incidence, Treatment, and Outcomes of Cardiac Arrest in the United States, 2003-2012.

Background Recent studies have shown improving survival after cardiac arrest. However, data regarding sex‐based disparities in treatment and outcomes after cardiac arrest are limited. Methods and Results We performed a retrospective analysis of all patients suffering cardiac arrest between 2003 and 2012 using the Nationwide Inpatient Sample database. Annual rates of cardiac arrest, rates of utilization of coronary angiography/percutaneous coronary interventions/targeted temperature management, and sex‐based outcomes after cardiac arrest were examined. Among a total of 1 436 052 discharge records analyzed for cardiac arrest patients, 45.4% (n=651 745) were females. Women were less likely to present with ventricular tachycardia/ventricular fibrillation arrests compared with men throughout the study period. The annual rates of cardiac arrests have increased from 2003 to 2012 by 14.0% ( P trend<0.001) and ventricular tachycardia/ventricular fibrillation arrests have increased by 25.9% ( P trend<0.001). Women were less likely to undergo coronary angiography, percutaneous coronary interventions, or targeted temperature management in both ventricular tachycardia/ventricular fibrillation and pulseless electrical activity/asystole arrests. Over a 10‐year study period, there was a significant decrease in in‐hospital mortality in women (from 69.1% to 60.9%, P trend<0.001) and men (from 67.2% to 58.6%, P trend<0.001) after cardiac arrest. In‐hospital mortality was significantly higher in women compared with men (64.0% versus 61.4%; adjusted odds ratio 1.02, P <0.001), particularly in the ventricular tachycardia/ventricular fibrillation arrest cohort (49.4% versus 45.6%; adjusted odds ratio 1.11, P <0.001). Conclusions Women presenting with cardiac arrests are less likely to undergo therapeutic procedures, including coronary angiography, percutaneous coronary interventions, and targeted temperature management. Despite trends in improving survival after cardiac arrest over 10 years, women continue to have higher in‐hospital mortality when compared with men.