cssi/SciSciGPT-SciSciNet huggingface dataset:
The ENU‐induced cetus mutation reveals an essential role of the DNA helicase DDX11 for mesoderm development during early mouse embryogenesis

Background: DDX11 is a DNA helicase of the conserved FANCJ/RAD3/XPD family involved in maintaining genome stability. Studies in yeast and humans have shown requirements for DDX11 in sister chromatid cohesion and DNA repair. In mouse, loss of Ddx11 results in embryonic lethality. However, the developmental defects of Ddx11 mutants are poorly understood. Results: We describe the characterization and positional cloning of cetus, a mouse ENU-induced mutation in Ddx11. We demonstrate that cetus causes a nonconservative amino acid change in DDX11 motif V and that this mutation is a null allele of Ddx11. cetus mutant embryos failed to thrive beyond embryonic day 8.5 and displayed placental defects similar to those described in Ddx11 null embryos. Additionally, our characterization of Ddx11cetus mutants identified embryonic phenotypes that had not been previously reported in Ddx11KO embryos, including loss of somitic mesoderm, an open kinked neural tube and abnormal heart looping. We show that loss of Ddx11 causes widespread apoptosis from early embryonic stages and that loss of Ddx11 disrupts somitic mesoderm more dramatically than other embryonic cells. Conclusions: Our results identify novel roles of Ddx11 during embryo morphogenesis and demonstrate that the activity of its motif V is essential for DDX11 function. Developmental Dynamics 241:1249–1259, 2012. © 2012 Wiley Periodicals, Inc.
STOPPING CROSS SECTION OF SOLIDS FOR PROTONS, 50-600 KEV

The stopping cross sections of Li, Cu, LiF, CaF2, Pb, and Au for protons have been measured over the energy range Ep=50-600 kev; the stopping cross section of Be for protons has been measured for Ep=50-2600 kev. An electrostatic analyzer and magnetic spectrometer were used to measure the energy loss of protons in a thin film of the stopping material. The density of the stopping film was determined by weighing, or by quantitative chemical analysis of, a known area. The ratio of the stopping cross section of Al, Cu, Mn, Ta, and Pb to that of Au was measured by observing the yield of elastically scattered protons from these targets for Ep=200-600 kev. The ratio of stopping cross section of Ca, V, Cr, Mn, Fe, Co, Ni, Cu, and Zn, to that of Mn was measured for Ep=200-600 kev by the same method. In the region Z=23-29, the stopping cross section decreases as the atomic number of the stopping material increases. The probable error of absolute stopping cross section measurements in this experiment is 3%.
The comprehensive assessment of community dwelling elderly: Why functional status is not enough

The present study attempts to determine empirically the relationship of measures of functional status to other domains common to geriatric assessment, and to ascertain whether functional status can substitute for other domains of clinical assessment. A comprehensive research survey was administered in the home to a randomly selected population of 4163 community residents aged 65 and over in the Duke EPESE, one of the four sites of the National Institute on Aging- funded Established Populations for Epidemiologic Studies of the Elderly. Sample members were predominantly black (55%), female (65%), between 65 and 74 years of age (61%), and lived in five contiguous counties within the state of North Carolina. Measurements included three measures of functional status ranging from basic activities of daily living (ADL) to strenuous mobility items, and summary measures of cognition, depression, and overall physical health. The three functional status measures were inter- correlated. However, with the exception of cognitive status and performance of instrumental ADL, the functional status measures failed to show a clinically significant relationship with the domains of cognition, depression, or overall physical health status. Furthermore, even among those sample members impaired in all three domains, 8% could still perform strenuous activities, and over 50% could still perform the basic activities of daily living. The data show that functional status measures are not necessarily indicative of an elder’s mental or physical health. Each domain of assessment contributes unique data, and no one area can fully substitute for another. (Aging Clin. Exp. Res. 6: 343–352, 1994)
The Spallation Products of Antimony Irradiated with High Energy Particles

The distribution and yields have been determined for a considerable number of spallation products resulting from the irradiation of antimony with particles in the 100-Mev range. The highest yields were found for nuclei about five mass numbers removed from the target material showing that compound nucleus formation is not an important mechanism in such high energy reactions. Products in lower yields were found which probably resulted from nuclei which had been excited to the full energy of the projectile. A more detailed discussion of the types of reactions responsible for the observed products is given.
Reassessment of riboflavin requirement for single comb White Leghorn pullets from 0 to 6 weeks of age fed on maize-soyabean meal diets and its subsequent effect on sexual maturity and egg production.

Abstract 1. Two experiments were conducted using a total of 228 Hyline W‐26 1‐d‐old pullets in each experiment. The purpose of the study was to reassess the riboflavin requirement from 0 to 6 weeks of age (WOA) and its subsequent effect on sexual maturity and egg production using a maize‐soyabean meal diet. 2. Approximately 10% incidence of curly toe paralysis was observed among birds fed on the diet with no added riboflavin (1.5 mg total riboflavin/kg diet). 3. Applying the non‐linear regression model to the body weight gain data at 3 and 6 WOA in both the experiments, it was found that the minimum total riboflavin required to acheive maximum body weight gain for the two age periods was 2.3 and 2.0 mg/kg of the total diet. This is equivalent to 5.0 and 5.7 μg riboflavin/g of body weight gain from 0 to 3 and 3 to 6 WOA respectively. 4. Birds fed on the diet containing no added (1.5 mg total/kg) riboflavin laid fewer eggs and had lower body weights at 24 weeks. 5. We conclude that, from 0 to 6 WOA, at leas...
Challenges Facing Community Colleges: Perceptions of Chief Academic Officers in Nine States

ABSTRACT Recent economic events and constantly-shifting priorities continue to challenge the traditional hallmarks of community colleges: responsiveness, adaptability, and flexibility. Institutional leaders are increasingly questioning whether the comprehensive community college model and, more importantly, open access, are still sustainable in today's austere funding environment. Drawing on research that predicted many of the unique issues and challenges currently plaguing community colleges, this study assessed the extent to which these items have come to fruition. A 9-state survey of community college chief academic officers provided insight regarding how their respective institutions have been impacted by these issues and challenges. The results indicated that fiscal matters remain the dominant challenge, as community colleges strive to “be all things to all people.” Without additional funding and/or new strategies, institutional leaders may face even greater challenges; most notably, dismantling the ...
Scattering of Protons by Hydrogen Near 18 Mev

The differential cross section for the scattering of 18.2\ifmmode\pm\else\textpm\fi{}0.2-Mev protons by hydrogen has been measured over the angular range 30\ifmmode^\circ\else\textdegree\fi{}-90\ifmmode^\circ\else\textdegree\fi{} in the center-of-mass system. In order to reduce the over-all errors to less than 1 percent a 60-in. scattering chamber was used. Polyethylene, polystyrene, and nylon foils were used as scatterers while the proton-proton events were detected by observing coincidences between the scattered and recoil protons in anthracene photomultiplier counters. The incident proton beam was collimated to \ifmmode\pm\else\textpm\fi{}14 minutes of arc. Probable relative errors varied from 0.5 percent at 90\ifmmode^\circ\else\textdegree\fi{} to about 1 percent at 30\ifmmode^\circ\else\textdegree\fi{}, while the probable error in the absolute differential cross section at 90\ifmmode^\circ\else\textdegree\fi{} is estimated to be 1 percent. The data show a significant deviation from pure $S$-wave scattering and are best fitted by taking $S$-, $P$-, and $D$-wave phase shifts to be ${k}_{0}=54.1\ifmmode^\circ\else\textdegree\fi{}$, ${k}_{1}=+1.0\ifmmode^\circ\else\textdegree\fi{}$, ${k}_{2}=+0.4\ifmmode^\circ\else\textdegree\fi{}$, respectively.
Characterization of flowering time and SSR marker analysis of spring and winter type Brassica napus L. germplasm

Flowering dates and life forms of all available Brassica napus accessions conserved at the North Central Regional Plant Introduction Station (NCRPIS) were characterized, and a survey of molecular variation was conducted by using simple sequence repeats (SSR) in order to support better management of accessions with diverse life forms. To characterize flowering phenology, 598 B. napus accessions from the NCRPIS collection were planted in Iowa and Kansas field sites together with a current commercial cultivar and observed for days to flowering (first, 50% and 100% flowering) in 2003. Days from planting to 50% flowering ranged from 34 to 83 in Iowa and from 53 to 89 in Kansas. The mean accumulated growing degree days (GDD) to 50% flowering were 1,997 in Iowa, and 2,106 in Kansas. Between locations, the correlation in flowering time (r = 0.42) and the correlation in computed GDD (r = 0.40) were both significant. Differences in flowering-time rank were observed for several accessions. Accessions that failed to flower in Iowa in a single growing season comprised 28.5% of the accessions; of the flowering accessions, 100% plant flowering was not always achieved. Accessions were grouped according to flowering time. A stratified sample of 50 accessions was selected from these groups, including 10 non-flowering and 40 flowering accessions of diverse geographic origins and phenological variation. The flowering time observed in the sampled accessions when grown in the greenhouse were found to be significantly correlated to the flowering time observed in the field locations in Iowa (r = 0.79) and Kansas (r = 0.49). Thirty SSR markers, selected across 18 Brassica linkage groups from BrassicaDB, and 3 derived from Brassica expressed sequence tags (ESTs) were scored in the stratified sample. An average of three bands per SSR primer pair was observed. Associations of SSR marker fragments with the life forms were determined. Analysis of molecular variation by using cluster analysis and ordination resulted in recognizable, distinct groups of annual and biennial life-form types, which may have direct applications for planning and management of future seed regenerations.
A Measure of Teacher Locus of Control

AbstractThis research was designed to construct an instrument, the Teacher Role Survey, to measure teachers* expectancies for internal or external control of important aspects of the work of teaching. Items were composed for initial trial based on 14 areas which past research has shown to be important satisfiers in teaching. The 75 items in the initial pool were administered to 321 teachers of varied teaching levels and years of experience who were enrolled in graduate courses in education. The Marlowe-Crowne Social Desirability Scale was administered as a measure of the influence of a generalized attitude of social desirability on item responding. Correlations of individual items with social desirability clustered around zero. Therefore, no items were eliminated because of susceptibility to the influence of social desirability . Based on the correlation with total score, 32 items were selected for inclusion in the final form of the Teacher Role Survey. Of the seven major logically construed categories or...
Effects of Phosphine–Carbene Substitutions on the Electrochemical and Thermodynamic Properties of Nickel Complexes

Nickel(II) complexes containing chelating N-heterocyclic carbene–phosphine ligands ([NiL2](BPh4)2, for which L = [MeIm(CH2)2PR2], MeIm = 1-methylimidizolylidene, and R = Ph or Et) have been synthesized for the purpose of studying how this class of ligand affects the electrochemical and thermodynamic properties compared to the nickel bis-diphosphine analogues. The nickel complexes were synthesized and then characterized by X-ray crystallography, electrochemical methods, and thermodynamic studies, including DFT calculations. On the basis of the reduction potentials (E°), substitution of an NHC for one of the phosphines in a diphoshine ligand resulted in negative shifts in potential by 0.6 to 1.2 V relative to the corresponding nickel bis-diphosphine complexes. From computational studies of the nickel hydride complex of the phenyl-substituted phosphine–carbene ligand, the hydride donor ability was determined to improve by 32 kcal/mol relative to the estimated hydride donor ability for the analogous nickel co...
The application of occupancy modeling to evaluate intraguild predation in a model carnivore system

Intraguild predation (IGP) is an extreme form of competition that involves a dominant predator (IG predator), a subordinate predator that is also a superior exploitative competitor (IG prey), and their shared prey. Theory predicts three possible equilibria, which parallel increasing resource enrichment: exclusion of the IG predator, stable coexistence, and exclusion of the IG prey. Here, we report on the existence of two concurrent states in a model carnivore system dominated by IGP. Using species occurrence data obtained from randomly distributed remote cameras, we modeled the probabilities of detection and occupancy of the kit fox (Vulpes macrotis) and its IG predator, the coyote (Canis latrans), at White Sands National Monument, New Mexico, USA, using a recently developed conditional two-species occupancy model. Kit foxes persisted in habitats of low resource abundance, which could not support coyotes. Coexistence occurred in adjacent habitats of higher resource enrichment, with coyote occupancy strong...
Clinical recognition of atrial myxoma

Abstract Those signs and symptoms sufficiently characteristic of atrial myxoma to alert physicians to their presence have been reviewed. They are the direct result of either inflow or outflow obstruction, tumor movement, presence of the tumor itself, or embolization of fragments of tumor or surrounding thrombus. Unless there is significant calcification of the tumor, the chest roentgenogram is of little diagnostic help. Electrocardiographic changes are nondiagnostic. The phonocardiogram, apex cardiogram, echocardiogram, cardiac radioisotope scan, and cardiac catheterization may provide data highly suggestive of the presence of an atrial tumor. Angiographic studies offer definitive diagnosis. The removal of the tumor generally results in amelioration of the signs and symptoms with the possible exception of atrioventricular valve incompetence and the rate tumor recurrence.
Coagulation factor levels in plasma frozen within 24 hours of phlebotomy over 5 days of storage at 1 to 6°C

BACKGROUND: The use of plasma frozen within 24 hours after phlebotomy (FP24) is likely to increase as male donors become the predominant source of plasma products. This study was performed to investigate the levels of clotting factors in thawed plasma (TP) prepared from FP24 during 5 days of storage at 1 to 6°C. STUDY DESIGN AND METHODS: Five units of A, B, and O and 3 units of AB FP24 were obtained from the local blood provider. They were thawed and maintained at 1 to 6°C for a total of 5 days. Within 6 hours of thawing and every 24 hours thereafter for 5 days, each unit was assayed for the following clotting factors: Factor (F)II, FV, FVII, FVIII, F IX, FXI, FXII, antithrombin (AT), protein C (PC), and protein S (PS). ADAMTS-13 was assayed on Days 2, 4, and 5. Time is expressed as mean hours or days (standard deviation). RESULTS: On average the units were frozen 21.3 (3.8) hours after phlebotomy and had been frozen for a mean of 30.1 (32.3) days before thawing. The activities of all procoagulant factors including FVIII, along with AT, PC, and ADAMTS-13, were well maintained in their normal range during the 5-day storage. The activity of PS was slightly below the normal range by Day 5. CONCLUSIONS: The activity of all factors assayed, except for PS, were within their normal range during the 5-day storage period. These results show comparable factor assay levels in TP prepared from fresh-frozen plasma and FP24.
Functional biochemical changes in bovine mammary cell cultures

Cell cultures up to 2 years in age and derived from bovine mammary glands were examined for some selected biochemical activities characteristic of normal secretory tissue. The ability to synthesize lactose decreased rapidly and disappeared from the cultures about 24 hr after their initiation, UDPGal-4-epimerase activity disappeared from the cultures between 7 and 10 days, but the ability to synthesize β-lactoglobulin was still present after 2 weeks. In general, there was a marked decrease within the first few days in the specific activities of a series of enzymes (alkaline and acid phosphatases, peroxidase, catalase, glucose-6-phosphate dehydrogenase, isocitric dehydrogenase, lactic dehydrogenase, DPN cytochrome c reductase, and hexokinase) when the activities in the cultures were compared with the original tissue. Smaller changes occurred after this time with no characteristic pattern. The results indicate that cell cultures derived from the bovine mammary gland, even though proliferating well and organizing into structures for several months, within a short time after being placed in culture begin to lose, but not simultaneously, specialized biochemical activities characteristic of normal secretory mammary tissue.
Magnetization creep in magnetic films

Magnetization reversal in planar magnetic films can occur for field amplitudes well below the static threshold. Repeated field transitions parallel to a film's hard axis in the presence of an easy-axis field can cause slow motion or creeping of the domain boundaries. Experimental observations of magnetization creep and proposed creep mechanisms are reviewed. Creep was studied in slow-rising sinewave and pulsed hard-axis fields. The effective creep thresholds obtained for these cases are compared. In an operating mode in which a bipolar easy-axis pulse and a unipolar word pulse are used, creep is reduced and the effective creep threshold is improved. Examples of domain growth in unipolar and bipolar hard-axis fields are shown in a series of Kerr optical photographs demonstrating the creep process.
Computer Literacy Requirements and Student Performance in Business Communications.

Abstract This study investigated whether completion of course prerequisites improves student performance in business communications. Regression analysis indicates that the freshman writing requirement improves course performance, whereas the computer literacy prerequisite has no effect. Students who complete the lower-division accounting course, though it is not a prerequisite, earn better grades in business communications. In addition, the study found that gender and class schedule have no effect on student outcomes.
Synthesis of nanoporous carbide-derived carbon by chlorination of titanium silicon carbide

Abstract Synthesis of nanoporous carbide-derived carbon, CDC, by extraction of titanium and silicon from Ti 3 SiC 2 by chlorine is discussed in this work. Thermodynamic simulations using a Gibbs free energy minimization program provided general guidelines to the experimental design. Raman spectroscopy, X-ray diffraction, and electron microscopy studies showed that the structure of CDC depends on the chlorination temperature. The low temperature synthesis resulted in an amorphous CDC structure. Noticeable graphite formation starts above 800 °C and well ordered graphite ribbons of 1–3 nm in thickness form at 1200 °C. The macroscopic volume and shape of Ti 3 SiC 2 preform were preserved during the transformation. However, the chlorination resulted in the formation of cracks between the former grains of the polycrystalline Ti 3 SiC 2 preform. These cracks are believed to be caused by a contraction in the direction perpendicular to the basal planes of Ti 3 SiC 2 . The synthesized nanoporous carbon demonstrated excellent sorption properties. Energy dispersive X-ray spectroscopy studies showed that Ti 3 SiC 2 material chlorinated at 400 °C is capable of trapping over 40 wt.% of Cl 2 .
Triple correlation of the 12C(p,p′γ)12C reaction

Abstract A triple correlation has been performed on the 12C(p,p′γ)12C reaction at the 3 2 + resonance (Ep = 5.37 MeV). Gamma-ray correlations for a set of angles between 0 and 150 degrees were taken for each of a set of proton angles from 40 to 150 degrees. The data were analysed according to the prescription of Kraus and indicate that the results may be explained assuming a resonant 3 2 − state interfering with a small mixture of 1 2 − state.
Fluorescence staining of living cells with fluorescamine.

The interaction of fluorescamine with living plant and animal cells was investigated to determine which subcellular structures and molecular species might react with the dye and to assess its effects on cell viability and function. Plasma and nuclear membranes ofXenopus erythrocytes, mitochondria of sea urchin sperm, growing apices of Timothy root hairs, and various organelles ofNitella andEuglena were labelled as judged by fluorescence microscopy. Cytoplasmic fluorescence was particulate inNitella and easily displaced by moderate centrifugal fields in sea urchin eggs. Chloroplasts and nuclei isolated from cells labelledin vivo exhibited fluorescamine dependent fluorescence. Reaction seemed to have little or no effect on cell viability (Euglena) photoautotrophic growth (Euglena), cell motility (sperm), fertilizability (sperm or egg), embryonic development (sea urchin), or cytoplasmic streaming (Nitella, Timothy). Quantitative fluorometric analysis of thein vivo reactants in sperm indicated a reaction preference for phospholipid over protein compared to control cells dissociated in SDS prior to labelling. The bulk of labelled lipid was phosphatidylethanolamine. These results suggest that fluorescamine is a true vital dye which can label the cell surface as well as penetrate deeply within cells to label a variety of organelles. The distribution of fluorescence and results of chemical analysis suggest thatin vivo the dye may preferentially react with membrane.
Western Blot Detection of PrPSc in Archived Paraffin-Embedded Brainstem from Scrapie-Affected Sheep:

Scrapie is a naturally occurring fatal neurodegenerative disease of adult sheep and goats, one of a group of mammalian diseases known as transmissible spongiform encephalopathies (TSE) or prion diseases. Immunoassays that identify disease-associated prion protein (PrP Sc) are integral to the diagnosis of scrapie and other prion diseases. Results obtained by either immunohistochemistry (IHC) or Western blot (WB) assay are generally adequate for the definitive diagnosis. Approved or accepted methods for WB diagnosis of TSEs requires the use of fresh or frozen nonfixed tissue samples, whereas formalin-fixed, paraffin-embedded tissue is required for the localization of PrP Sc by IHC. Because disparate processing methods are used for these accepted diagnostic techniques, separate tissue samples are collected from the same animal. Occasions arise in which there is either insufficient quantity of tissue available to complete analysis by both techniques or initial tissue processing is incompatible with one of the assays. Also, results between the assays may differ because of the vagaries of sampling, especially in case material that contains moderate-to-low levels of PrP Sc. The present article describes a method to conduct a WB assay from the same paraffin-embedded brainstem sample used for the IHC diagnosis of experimentally induced sheep scrapie.
Improving GPS Service via Social Collaboration

The popularity of GPS-enabled smartphones enables a wide variety of new location-based or location-aware services and applications. However, the GPS module in a smartphone produces inaccurate position estimates and incurs high energy consumption, which inhibits the wide use of location-aware applications. To address this, we propose a social-aided cooperative location optimization (Coloc) scheme, which is capable of improving positioning accuracy and achieving low energy consumption. Specifically, our scheme enhances positioning accuracy by fusing the GPS positions of multiple co-located smartphones in a social network, or by neighborhood-based weighted least-squares estimation when relative distances between smartphones are available. The energy efficiency is achieved by sharing location information among co-located users and lower the update rate of the GPS module without sacrificing the accuracy. To validate our proposed approach, we conduct experiments in stationary and moving scenarios. Experimental results show that our proposed cooperative localization scheme can achieve sufficient performance gains in both indoor and outdoor environments.
Differential serum protein binding of benzidine- and benzidine-congener based dyes and their derivatives.

Environmental dyes and their derivatives, some of which are genotoxic, must be transported within the body to the tissues which they affect. One mechanism for this can be observed directly by crossed immunoelectrophoresis (X-IEP). Binding of these chemicals to certain serum proteins changes electrophoretic and immunoprecipitation morphology in X-IEP patterns. This is demonstrated here for four azo dyes derived from benzidine, 3,3′-dimethylbenzidine, and 3,3′-dimethoxybenzidine, and their parent aromatic amines. Direct Red 2 (a 3,3′-dimethylbenzidine-based dye), Direct Blue 15 (a 3,3′-dimethoxybenzidine-based dye), Direct Black 38 (a benzidinebased dye), and Evans Blue (a 3,3′-dimethylbenzidine-based dye) all bound to albumin, α1-lipoprotein, β-lipoprotein, and hemopexin. Direct Red 2 only slightly affected the mobilities of these proteins. Direct Blue 15 bound also to prealbumin and α1-antichymotrypsin, and degraded C3 globulin. Direct Black 38 and Evans Blue bound to numerous additional proteins. Evans Blue bound variably to proteins of sera from different individuals, suggesting that there are individual differences in serum protein binding capabilities for these chemicals. Of the three derivatives of the benzidine dyes, only 3,3′-dimethylbenzidine caused changes in X-IEP patterns, indicating its binding to the serum proteins. This chemical differentially affected sub-populations of α1-lipoprotein, either by altering its electrophoretic mobility or inhibiting its recognition by antibodies. Autoradiographic analyses demonstrated the binding of benzidine and 3,3′-dimethylbenzidine to both α1- and β-lipoproteins.
What are the Contents of Experiences

I address three interrelated issues concerning the contents of experiences. First, I address the preliminary issue of what it means to say that experiences have contents. Then I address the issue of why we should believe that experiences have contents. Finally, I address the issue of what the contents of experiences are.
Resolving Toric Varieties with Nash Blowups

It is a long-standing question whether an arbitrary variety is desingularized by finitely many normalized Nash blowups. We consider this question in the case of a toric variety. We interpret the normalized Nash blowup in polyhedral terms, show how continued fractions can be used to give an affirmative answer for a toric surface, and report on a computer investigation in which over a thousand 3- and 4-dimensional toric varieties were successfully resolved.
An Improved 2-element Independently Center-Fed Dipole Array for Ultra-Wideband

This paper analyzed the efficiency of independently center-fed dipole array (ICDA) antenna. The best design was achieved with an array composed of two diamond antennas. It was demonstrated that the ICDA is capable of combining the bandwidths of both elements while maintaining linear phase throughout a broader bandwidth than the UWB requirements. Such characteristics make this antenna very appealing for ultra-short pulse and ultra-wideband applications
Helping Hispanic-America vote? Ballot technology, voter fatigue and HAVA 2002

Lott (2009) finds that nonvoted ballot rates for down-ballot races are greater than those for presidential races, and newer technologies that reduce nonvoted presidential ballots create even greater rates of nonvoting down-ballot than the same older voting technologies. The conclusion is momentous: adopting voting technologies that minimize under-voting in presidential races actually increases under-voting across all races on the same ballot. This study extends Lott's by examining the Congressional vote on the Help America Vote Act of 2002 (HAVA 2002), which established a program to provide funds to states in order to replace punch card voting systems with newer technologies. We focus on the racial component of Lott's finding, specifically that Hispanic-American voters exhibit greater rates of voter fatigue than do white voters. This study posits that, given the large Hispanic-American populations in California and Texas and their propensity to support Democrats in these states, House Democrats from these...
SIR and outage contours in 2-hop relaying cellular networks

The paper calculates intra-cell interference introduced by the addition of relays in a CDMA type cellular network. Signal-to-interference ratio (SIR) contours are plotted to show the spatial variation. Outage contours show the areas where signals fall below threshold due to the addition of relays. The study aims to give an optimum number of relays for a given SIR threshold.
Endogenous inhibin suppresses only basal follicle-stimulating hormone secretion but suppresses all parameters of pulsatile luteinizing hormone secretion in the diestrous female rat.

The purpose of these studies was to ascertain which parameters of pulsatile gonadotropin secretion are regulated by endogenous inhibin in the intact diestrous female rat. This was determined by examining the changes in the secretion parameters of FSH and LH that resulted from immunoneutralizing endogenous inhibin in diestrous I female rats. Passive immunoneutralization of endogenous inhibin was achieved using specific, high titer ovine antiserum generated against the alpha-subunit of the recently described inhibin molecule. The optimal times after inhibin immunoneutralization to observe the changes in FSH secretion were determined in initial experiments. Pulsatile secretion of both FSH and LH was observable in the diestrous female. Two hours after inhibin immunoneutralization, the mean trough level, mean peak level, and overall mean level of FSH began to increase. The maximal increase and plateau of these parameters were observed 5 h after antiserum injection. During the period of increase, mean FSH pulse amplitude was also increased, but returned to the level observed in control (normal sheep serum-injected) animals when the parameters of trough, peak, and overall mean FSH reached their plateau levels. FSH pulse frequency was not changed at any time. These results indicate that endogenous inhibin affects only the basal parameters of FSH secretion without affecting pulsatile FSH secretion. The transient increase in FSH pulse amplitude resulted from FSH pulses being superimposed on the increasing basal FSH secretion. In contrast, immunoneutralization of endogenous inhibin rapidly increased all parameters (i.e. pulse amplitude and frequency, mean trough and peak levels, and mean plasma levels) of LH secretion. In addition, pituitary sensitivity to an exogenous LHRH challenge was increased in inhibin-immunoneutralized females in terms of stimulated LH secretion. As a result of the already increased rate of basal secretion, the actual quantity of FSH released in response to the LHRH challenge was greatly increased in the inhibin-immunoneutralized rats compared with the normal sheep serum-injected controls; however, the increase in the rate of FSH secretion stimulated by the LHRH challenge was the same in both groups. The observations from these studies collectively demonstrate that inhibin acts endogenously to suppress those parameters of gonadotropin secretion that are regulated by LHRH.
Identifying important and difficult concepts in introductory computing courses using a delphi process

A Delphi process is a structured multi-step process that uses a group of experts to achieve a consensus opinion. We present the results of three Delphi processes to identify topics that are important and difficult in each of three introductory computing subjects: discrete math, programming fundamentals, and logic design. The topic rankings can be used to guide both the coverage of standardized tests of student learning (i.e., concept inventories) and can be used by instructors to identify what topics merit emphasis.
Aneurysm Formation After Laser-Assisted Microvascular Anastomosis: Etiology, Growth Rate, and Prevention

Aneurysm formation has been a major complication in laser-assisted micro vascular anastomosis (LAMA). The authors investigated the effect of increased laser energy on the formation and growth rate of aneurysms. In addition, possi ble methods of prevention were reviewed. End-to-end anastomoses were per formed on 89 rat femoral arteries with the placement of three stay sutures (120 degrees apart) followed by application of CO2 laser irradiation (power = 80 mW, pulse mode = 0.2 s, spot size = 0.275 m). In Group I (N=55), anasto moses were performed with 45 laser pulses, and in Group II (N = 34) 135 laser pulses were used. Each disruption of an anastomosis was repaired by use of 15 additional laser pulses. Six of 18 aneurysms in Group I were reevaluated at weeks 1, 3, and 8 to assess growth rate. All vessels were examined at week 3 for patency and aneurysm formation.Overall aneurysm rates in the two groups were similar, despite the increased laser energy used in Group II (p > 0.05). There was a higher inciden...
Frankia bacteria in Alnus rubra forests: genetic diversity and determinants of assemblage structure

To quantify the genetic diversity of Frankia bacteria associated with Alnus rubra in natural settings and to examine the relative importance of site age, management, and geographic location in structuring Frankia assemblages in A. rubra forests, root nodules from four A. rubra sites in the Pacific Northwest, USA were sampled. Frankia genetic diversity at each site was compared using sequence-based analyses of a 606 bp fragment of the nifH gene. At a 3% sequence similarity cutoff, a total of 5 Frankia genotypes were identified from 317 successfully sequenced nodules. Sites varied in the total number of genotypes present, but were typically dominated by only one or two genotypes. Phylogenetic analyses showed that all of the A. rubra-Frankia genotypes grouped with other Alnus-infective Frankia. Analysis of similarity (ANOSIM) and chi-square analyses indicated that Frankia assemblages were more strongly influenced by site age/management than geographic location. This study demonstrates that the Frankia assemblages in A. rubra forests have low genotype diversity, but that genotype abundance can differ significantly in forests of different age/management history.
Spatiotemporal dynamics of the postnatal developing primate brain transcriptome

Developmental changes in the temporal and spatial regulation of gene expression drive the emergence of normal mature brain function, while disruptions in these processes underlie many neurodevelopmental abnormalities. To solidify our foundational knowledge of such changes in a primate brain with an extended period of postnatal maturation like in human, we investigated the whole-genome transcriptional profiles of rhesus monkey brains from birth to adulthood. We found that gene expression dynamics are largest from birth through infancy, after which gene expression profiles transition to a relatively stable state by young adulthood. Biological pathway enrichment analysis revealed that genes more highly expressed at birth are associated with cell adhesion and neuron differentiation, while genes more highly expressed in juveniles and adults are associated with cell death. Neocortex showed significantly greater differential expression over time than subcortical structures, and this trend likely reflects the protracted postnatal development of the cortex. Using network analysis, we identified 27 co-expression modules containing genes with highly correlated expression patterns that are associated with specific brain regions, ages or both. In particular, one module with high expression in neonatal cortex and striatum that decreases during infancy and juvenile development was significantly enriched for autism spectrum disorder (ASD)-related genes. This network was enriched for genes associated with axon guidance and interneuron differentiation, consistent with a disruption in the formation of functional cortical circuitry in ASD.
What we Know About What we Know About Toxic Polluter Behavior from the TRI: Evidence from (almost) Twenty Years of TRI Data in The Petroleum Refining Industry.

Using the TRI to understand polluting behavior can pose challenges due to the limited number of chemicals that are reported, the potential confounding effect of several regulatory programs that affect TRI substances, the lack of output information, and judgments regarding appropriate measures of releases. In an effort both to help illustrate and clarify these issues, I study TRI data from the petroleum refining industry using a balanced panel of 199 refineries from 1988-2003. I find that (1) although both aggregate and toxicity-weighted releases exhibited large declines over the period of study, the pattern of releases were substantially different, strongly suggesting that any inference that is drawn from the data will be sensitive to the measure of releases; and (2) regulatory programs can affect TRI releases both directly and indirectly. The direct effect occurs because emissions of several TRI substances are simultaneously regulated under the CAA and CWA (and other environmental programs and policies. The indirect effect occurs when regulatory programs induce changes in the set of inputs or the production process, leading to changes in TRI releases of substances that are not directly regulated under these programs. Thus, simply “netting-out” CAA and CWA substances from the TRI will not necessarily remove the confounding effects of these regulatory programs.
Musicians and tone-language speakers share enhanced brainstem encoding but not perceptual benefits for musical pitch

Behavioral and neurophysiological transfer effects from music experience to language processing are well-established but it is currently unclear whether or not linguistic expertise (e.g., speaking a tone language) benefits music-related processing and its perception. Here, we compare brainstem responses of English-speaking musicians/non-musicians and native speakers of Mandarin Chinese elicited by tuned and detuned musical chords, to determine if enhancements in subcortical processing translate to improvements in the perceptual discrimination of musical pitch. Relative to non-musicians, both musicians and Chinese had stronger brainstem representation of the defining pitches of musical sequences. In contrast, two behavioral pitch discrimination tasks revealed that neither Chinese nor non-musicians were able to discriminate subtle changes in musical pitch with the same accuracy as musicians. Pooled across all listeners, brainstem magnitudes predicted behavioral pitch discrimination performance but considering each group individually, only musicians showed connections between neural and behavioral measures. No brain-behavior correlations were found for tone language speakers or non-musicians. These findings point to a dissociation between subcortical neurophysiological processing and behavioral measures of pitch perception in Chinese listeners. We infer that sensory-level enhancement of musical pitch information yields cognitive-level perceptual benefits only when that information is behaviorally relevant to the listener.
Ethical Issues in End-Stage Liver Disease: A Framework for Assessment and the Challenges

Complex ethical issues can arise in patients with end-stage liver disease (ESLD). Fortunately, frameworks such as the “four topics approach” exist to allow a practical and organized approach to the analysis of these ethical issues and should be routinely employed. The demographics of patients, the presence of hepatic encephalopathy, and the uncertainty of prognostic models present challenges to the evaluation of ethical issues in patients with ESLD. Specific ethical issues in these patients include a bias against patients with alcoholism and drug abuse, liver transplantation for alcoholic hepatitis, legal marijuana use, and organ allocation for liver transplantation.
Morphology and fine structure of Barbus barbus (Teleostei: Cyprinidae) spermatozoa

Summary Morphology and fine structure of Barbus barbus L 1758 spermatozoa were studied using scanning (SEM) and transmission (TEM) electron microscopy. The results confirm that spermatozoa exhibit morphological features typical to all teleost fishes. They are differentiated into a head, a midpiece and a flagellum with the typical ‘9 + 2’ pairs of microtubules. Both dynein arms are present in the flagellum. The spermatozoa have spherical nuclei, 4–6 mitochondria located in the postnuclear cytoplasmic region and centriolar complex (proximal and distal centrioles). Total length, head width, length of midpiece and length of flagellum were measured to be 56.35 ± 7.42, 1.80 ± 0.06, 0.48 ± 0.14 and 54.30 ± 6.97 μm, respectively. Highly significant linear correlation was observed between posterior and anterior width of midpiece (P < 0.01). Principal component analysis (PCA) was used to explore which parameters can explain the individual variation of sperm morphology. About 44% of the total accumulated variance was absorbed by the analysis of the two first components, distinguishing different groups of parameters related to head and midpiece. The lengths of flagellum and head are more isolated; indicating that the individual variation of sperm morphology depends on these two parameters. Comparing the results of this study with information on cyprinids spermatozoa reveals that the number of mitochondria and the length of the flagellum are good characters to characterize spermatozoa of the Cyprinidae in a phylogenetic arrangement.
An Age-Related Decrease in Creatinine Clearance Is Associated with an Increase in Number of Falls in Untreated Women But Not in Women Receiving Calcitriol Treatment

Context: Decreased calcitriol production due to impaired renal function may be a significant risk factor for falls in normal aging population. Objective: The objective of the study was to examine the association between creatinine clearance (CrCl) and the incidence of falls and fallers in groups treated with placebo, calcitriol, estrogen therapy (ET)/estrogen + progestin therapy (HT), and calcitriol + ET/HT. Design: This was a 3-yr, double-blind, placebo-controlled study designed to test the efficacy of calcitriol and ET/HT on bone loss and falls with analysis by intention to treat and post hoc. Setting: The study was conducted at an academic outpatient center. Participants: Four hundred eighty-nine normal elderly women aged 65–77 yr; 415 women completed the study. Intervention: Subjects were randomized to placebo, calcitriol 0.25 μg twice a day, ET daily (conjugated equine estrogens 0.625 mg), HT (conjugated equine estrogen 0.625 mg + medroxyprogesterone acetate 2.5 mg) and calcitriol + ET/HT. Main Outco...
Distributed control design for systems interconnected over an arbitrary graph

We consider the problem of synthesizing a distributed dynamic output feedback controller achieving H/sub /spl infin// performance for a system composed of different interconnected sub-units, when the topology of the underlying graph is arbitrary. First, using tools inspired by dissipativity theory, we derive sufficient conditions in the form of finite-dimensional linear matrix inequalities when the interconnections are assumed to be ideal. These inequalities are coupled in a way that reflects the spatial structure of the problem and can be exploited to design distributed synthesis algorithms. We then investigate the case of lossy interconnection links and derive similar results for systems whose interconnection relations can be captured by a class of integral quadratic constraints that includes constant delays.
Introduction: Cross-Racial and Cross-Ethnic Collaboration and Scholarship: Contexts, Criticism, Challenges

My interest in editing a special issue of MELUS devoted to cross-racial and cross-ethnic collaboration and scholarship evolved from my investigation of newspaper accounts by and about the nineteenth-century Northern Paiute author and activist Sarah Winnemucca Hopkins. These items present increased evidence regarding Winnemucca’s productive interracial collaboration with her editor Mary Peabody Mann, her manager and friend Elizabeth Palmer Peabody, and her husband Lewis H. Hopkins. Many nineteenth-century accounts of these relationships replicate their era’s racism, representing Winnemucca’s husband in language evoking a “squaw man” and calling Peabody’s relationship with Winnemucca “ ac urious idiosyncrasy” (“Current”). Even Mann, who, as Heidi M. Hanrahan’s essay in this issue demonstrates, had a positive relationship with Winnemucca, nonetheless called Winnemucca Peabody’s “pet Indian” (qtd. in Zanjani 280). Winnemucca, in turn, was at times accused of duping nao ¨ve non-Natives. There was something unsettling to many about the possibility that Winnemucca was working with non-Natives productively—that together they may have been enacting their versions of interracial friendship, love, or political and artistic collaboration. Critical accounts written in the past few decades replicate this suspicion, effectively stripping Winnemucca of agency in her life and work. 1 In American Indian literary studies, some scholars are reconsidering collaboration and revising assumptions about American Indian passivity or nao ¨vete ´. 2 Aware of these changes, I was curious about how new work in other areas of race and ethnic studies resulted in revised narratives of cross-racial and cross-ethnic collaboration. I had in mind neither exclusively commendatory nor condemnatory reconsiderations, wanting to avoid what Lorraine M. York describes in relation to women’s collaborative writing: scholarship that supplants “deplorably subversive” representations of collaborations with ones that are “admirably subversive” (9). I sought a diversity of scholarship urging us to consider the ethical and practical implications of the stories we tell about interracial or interethnic collaboration. The call for submissions sought new biographical information, new critical interpretations of previously studied cross-racial or cross-ethnic collaborations, reexaminations of the representation of cross-racial or ethnic collaboration within literary and cultural studies, and contemporary scholars’ reflections on their own experiences of interracial and interethnic collaboration. Because my experience with Winnemucca convinced me that in many cases, we lack or have not looked for the archival