cssi/SciSciGPT-SciSciNet huggingface dataset:
Evidence that physical dependence on morphine is mediated by the ventral midbrain

Rats were given daily injections of increasing doses of morphine sulfate (40-100 mg/kg, s.c.), for 4 days. Twenty hours after the last injection of morphine, the animals received bilateral injections of naloxone (1-10 micrograms) into the substantia nigra, ventral tegmental area or sites 2 mm rostral, caudal or dorsal to the site in the nigra. Withdrawal signs were monitored for 20 min after the intracerebral injection. Naloxone administered into the nigra in morphine-dependent rats produced dose-dependent significant increases in wet dog shakes, irritability to touch, teeth chattering, diarrhea and locomotion, compared to morphine-dependent animals that received injections of saline into the nigra. The injection of naloxone (3 micrograms) into the ventral tegmental area of morphine-dependent animals, produced irritability to touch and diarrhea, compared to morphine-dependent controls that received saline in this region of the brain. Significant differences in withdrawal signs were observed between morphine-dependent animals, that received injections of naloxone (3 micrograms) into the nigra and those that received naloxone (3 micrograms) into the ventral tegmental area or rostral or caudal sites. No differences between the substantia nigra and the dorsal sites were observed. However, withdrawal symptoms were produced by injections of naloxone into the substantia nigra and ventral tegmental area, even when the guide cannulae were angled to avoid penetration of sites dorsal to these regions of the brain. Naloxone, injected into the ventral midbrain of non-dependent animals, produced no signs of withdrawal. These studies suggest that the ventral midbrain mediates physical dependence on morphine.
Impact of Culture on Knowledge Management: A Meta-Analysis and Framework

Culture, both national and organizational, can have profound impacts on knowledge management. Yet the literature on exactly how culture impacts knowledge management is complex with no clear generalizable results. A meta-analysis was conducted on 52 articles from ten IS journals for the years 2000–2010 combining both quantitative and qualitative studies in a unique methodological approach. Key findings include a marked shift away from normative language towards more interpretive and critical discourse emphasizing the power issues inherent in the cultural context of knowledge management. Trust and openness are key organizational cultural dimensions that impact knowledge management processes, but these traits are achieved through effective business leadership, rather than a particular technological artifact. The most striking generalizable finding from the cross-case analysis is that organizational culture can overcome or mitigate differences in national culture. An overall framework is provided to illustrate the findings and to serve as an important guidepost for future research.
pH-Responsive Artemisinin Dimer in Lipid Nanoparticles Are Effective Against Human Breast Cancer in a Xenograft Model

Artemisinin (ART), a well-known antimalaria drug, also exhibits anticancer activities. We previously reported a group of novel dimeric artemisinin piperazine conjugates (ADPs) possessing pH-dependent aqueous solubility and a proof-of-concept lipid nanoparticle formulation based on natural egg phosphatidylcholine (EPC). EPC may induce allergic reactions in individuals sensitive to egg products. Therefore, the goal of this report is to develop ADP-synthetic lipid particles suitable for in vivo evaluation. We found that ADP binds to 1,2-dipalmitoyl-sn-glycero-3-phosphocholine (DPPC) with greater than 90% efficiency and forms drug-lipid particles (d ∼ 80 nm). Cryo-electron microscopy of the ADP drug-lipid particles revealed unilamellar vesicle-like structures. Detailed characterization studies show insertion of the ADP lead compound, ADP109, into the DPPC membrane and the presence of an aqueous core. Over 50% of the ADP109 was released in 48 hours at pH4 compared with less than 20% at neutral. ADP109-lipid particles exhibited high potency against human breast cancer, but was tolerated well by nontumorigenic cells. In MDA-MB-231 mouse xenograft model, lipid-bound ADP109 particles were more effective than paclitaxel in controlling tumor growth. Cellular uptake studies showed endocytosis of the nanoparticles and release of core-trapped marker throughout the cytosol at 37°C. These results demonstrate, for the first time, the in vivo feasibility of lipid-bound ART dimer for cancer chemotherapy.
Barriers to early pediatric cochlear implantation

Abstract Objectives Universal newborn hearing screening has significantly improved the ability to identify patients with congenital sensorineural hearing loss (SNHL), which results in earlier treatment and better hearing and development outcomes. It is recommended that patients born with SNHL who meet criteria receive cochlear implants (CIs) by a target age of 12 months, however many children are being implanted at an older age. This study aims to describe populations of pre-lingual patients with SNHL that are at risk for delayed implantation and to identify and analyze barriers that cause this delay. Methods Charts of patients receiving a CI between January 2008 and June 2012 at a tertiary care cochlear implant center were reviewed retrospectively. We looked at patient demographics, age at hearing loss diagnosis, age at implantation, and etiology of hearing loss. Barriers to implantation were identified through surveys completed by team members. Results Fifty-seven CI recipients were identified of which 42 were in patients with pre-lingual SNHL. SNHL etiology included: cochlear dysplasia (18%), GJB2/GJB6 (17%), acquired (10%) extreme prematurity (9%), and idiopathic (46%). The median age of SNHL diagnosis for pre-lingual patients was 15 months. Compared to private insurance, public insurance status was associated with SNHL diagnosis at a significantly later median age (20.0 vs. 4.0 months, p = 0.024), and with a significantly longer median interval from diagnosis to implantation (25.5 vs. 11.0 months, p = 0.029). While cochlear implant team members identified delayed insurance approval and medical comorbidities as reasons for delayed implantation, the most significant factor identified was parental, with delayed/missed appointments or reluctance for evaluations or surgery. Conclusion 52% of patients with pre-lingual SNHL that met criteria for CI were implanted more than 12 months after diagnosis. Having public or no insurance was significantly associated with delayed implantation. Parental barriers were most common factors cited for delays in implantation. Overcoming these delays necessitates appropriate identification of at risk patients and creating a system to educate families and chaperone them through the process.
Ecoregions of the Conterminous United States

Abstract A map of ecoregions of the conterminous United States has been compiled to assist managers of aquatic and terrestrial resources in understanding the regional patterns of the realistically attainable quality of these resources. The ecoregions are based on perceived patterns of a combination of causal and integrative factors including land use, land surface form, potential natural vegetation, and soils. A synoptic approach similar to that used to define these ecoregions is also useful for applications of the map. Initial efforts to use the framework are at the state level of resource management; they center on aquatic ecosystems — mainly attainable ranges in chemical quality, biotic assemblages, and lake trophic state.
Effects of randomness of grain boundary resistance on fatigue initiation life

In the framework of crack number density analysis, a theoretical investigation is carried out on the relationship between the statistical characteristics of fatigue initiation life and the stochastic growth of short fatigue cracks. The numerical results indicate that, compared with the influence of grain boundary resistance, the effect of the degree of randomness of crystallographic crack growth is only secondary.
Resource allocation during the rereading of scientific texts

Two experiments examined how cognitive resources are allocated to comprehension processes across two readings of the same scientific texts. In Experiment 1, readers read and later reread texts describing scientific topics. The results indicated that across readings, readers decreased resources allocated to proposition assembly, increased resources allocated to text-level integration, and expended a similar amount of resources to lexical access. Subjects who reread the texts after a week delay showed a similar pattern, except that they did not show the increase for text-level integration. Experiment 2 revealed a similar pattern of results with a moving window procedure, except that there was a significant decrease in resources allocated to lexical access across exposures. This experiment also indicated that the rereading speedup was greatest at sentence boundaries, suggesting that the prior exposure enabled readers to immediately process each word. Overall, the results are consistent with the claim that readers allocate proportionally more available resources to text-level integration during rereading because proposition assembly, which enables text-level integration, can be completed with fewer resources.
Two trajectories of democratic capitalism in the post-war Chicago school: Frank Knight versus Aaron Director.

The Chicago school of economics has long emphasised the efficiency of decision makers in a competitive economic order in comparison to those in a democratic political order. The purpose of our article is to show that this emphasis emerged from two different re-conceptualisations of liberal democracy by Chicago economists during the post-war period The first was Frank H. Knight’s enquiry into whether rational norms for intelligent democratic action provided the means to avoid the failures of liberalism that had become so apparent through the upheavals of the first several decades of the twentieth century. The second came from Aaron Director, who concluded instead that democratic action was inherently irrational and disputatious, and that the efficiency of actions undertaken with the context of the competitive order was to be preferred. Knight argued that an appreciation for competition must be accompanied by recognition of the equally fundamental roles of democratic discussion and ethics, whilst Director asserted the fundamental role of competition in the economic realm and its import for freedom.
Lovastatin enhances phenylbutyrate-induced MR-visible glycerophosphocholine but not apoptosis in DU145 prostate cells.

Abstract In this study the effects of lovastatin on DU145 prostate cancer cells treated with phenylbutyrate (PB) was investigated in order to determine the NMR-detectable metabolic changes resulting from the cooperative activity of these two agents. DU145 cells were perfused with PB in the presence or absence of 10 μM of the HMG-CoA reductase inhibitor lovastatin, and the results monitored by 31P and diffusion-weighted 1H NMR spectroscopy. Lovastatin had additive effects on the PB-induced NMR-visible total choline in 1H spectra, and glycerophosphocholine in 31P spectra but no significant effect on NMR-visible lipid. Moreover, lovastatin had no effect on the ability of PB to either promote the formation of oil red O-detectable lipid droplets or arrest the cell cycle. The most remarkable observations from these studies were that lovastatin enhanced the increase in glycerophosphocholine while reversing late markers of apoptosis and the loss of NTP caused by PB. These results identify a branch point separating the neutral lipid production and the apoptotic cell death caused by the actions of differentiating agents.
Evaluating ESL: Making sense of university professors’ responses to second language writing

Abstract This study addresses the response of social science and engineering science faculty to a naturally occurring sample of second language writing. Using a matched-guise protocol, faculty participants were led to believe that the one-page essay was produced by an international student whose first language was either Chinese or Spanish. The faculty evaluated the writing holistically (on a scale from 1 to 10) and were invited to “correct the five most troublesome errors.” Results indicate that the ethnic guise did not affect holistic scores; however, the social science and engineering science faculty did rate the composition differently. While qualitative analysis demonstrates that, not surprisingly, individual editing styles among faculty are quite variable, there was a tendency across faculty to edit semantic gaps as opposed to grammatical items. This indicates a preference by the faculty to clarify content, a finding that supports prior research.
An "Incomplete" Picture? Race, Latino Migration, and Urban Politics in Nashville, Tennessee

This article examines Latino migration's effects on understandings of race, structures of racial hierarchies, and terms of racial politics in Nashville, Tennessee, a metropolis that has experienced rapid Latino population growth since the mid-1990s. Drawing on an analysis of both a series of interviews with key actors across Nashville and a series of urban controversies in the late 1990s, it queries the contradictory place that Latino/as occupy in metropolitan Nashville's racial formations and practices. On the one hand, Latino/as, as a racially marked group, are ambiguously situated in Nashville's racial categories and hierarchy. On the other hand, key events and political conflicts at least temporarily crystallize Nashville's racial fault lines and alliances, placing Latino/as squarely within debates concerning social justice and racial solidarity. The article concludes by reflecting on the implications of the "incomplete" picture of Latino migration's effects on race and cultural belonging in Nashville...
Progression of coronary artery disease after percutaneous transluminal coronary angioplasty.

Abstract Thirty-nine patients underwent coronary arteriography 1 to 20 months (mean 7 months) after percutaneous transluminal coronary angioplasty (PTCA). At the time of the repeat study 65 patients (90%) had recurrent angina or myocardial infarction, and 4 patients (10%) were asymptomatic. Restenosis, defined as >50% loss of PTCA gained diameter, was found in 19 patients (49%). In addition, 20 patients had new lesions or marked progression of existing lesions (defined as >20% or increasing >20% obstruction in coronary ciameter) in the previously normal or mildly diseased coronary segments. The new or progressive lesions occurred both in patients with restenosis at the PTCA site (nine of 19) and in patients without restenosis (91 of 20). New or progressive lesions tended to occur more commonly in the artery on which PTCA was performed (13 of 40) than in the artery that did not have PTCA (10 of 77) ( p 2 ). In arteries that had PTCA, new or progressive lesions occurred more often in the segment proximal to the angioplasty site (seven to 13 or 54%) than in the peri-PTCA segment (two of 13 or 15%) and in the segments distal to it (four of 13 or 31%), but this observation did not reach statistical significance. No other clinical, angiographic, or PTCA procedure variables affected the occurrence of new or progressive lesions. In patients with recurrent angina or myocardial infarction after PTCA, both restenosis and new or progressive lesions are common. New lesions or marked progression of existing lesion tended to occur in the vessel subjected to PTCA. Arterial trauma during the PTCA procedure could be considered a possible mechanism for progression of coronary artery disease after coronary angioplasty.
Rickettsia tsutsugamushi in chiggers (Acari: Trombiculidae) associated with rodents in central Thailand.

Chiggers were collected from rodents trapped at two military bases located 10 km apart in central Thailand. One site was swampy and nearly treeless and the other site was well-drained and partially wooded. Although 13 species of chiggers were collected, only three species were found to be positive for Rickettsia tsutsugamushi (Hayashi) Ogata using a direct fluorescent antibody test: Blankaartia acuscutellaris Walch (7.3% infected), Leptotrombidium deliense Walch (3.1% infected), and an undescribed species of Ascoschoengastia near A. indica Hirst (1.2% infected). This was the first record of R. tsutsugamushi in B. acuscutellaris . The Ascoschoengastia species occurred with equal frequency at the two study sites, L. deliense occurred more frequently at the well-drained site, and B. acuscutellaris occurred more frequently at the swampy site. Results suggest that there are important foci of scrub typhus in central Thailand and that B. acuscutellaris may be a vector in this area.
Pulmonary physiologic changes of morbid obesity.

ABSTRACT Objective: Our objective was to study the effects of extreme obesity on pulmonary function tests and the effects of smoking on these variables in a population group larger than has previously been reported. Design: Retrospective data analysis. Setting: Academic medical center. Patients: Forty-three patients with extreme obesity [ratio of weight in kilograms to height in centimeters greater than 0.9 (W/H)] who underwent pulmonary function testing at Cedars-Sinai on an out-patient or in-patient basis during the period of 1979 to 1997. Measurements and Results: Patients underwent standard pulmonary function testing. The patients were divided into 2 groups based on the W/H ratio: group A (0.9-0.99) and group B (greater than 1.0). Chart review was performed to identify pertinent historyl co-morbidities. The independent effects of smoking between each group's patients were assessed. Forced vital capacity (FVC), forced expiratory volume in 1 second (FEV1), expiratory reserve volume (ERV), functional residual capacity (FRC), maximum voluntary ventilation (MVV), and forced expiratory flow during midexpiratory phase (FEF 25–75% ) were significantly reduced in both groups. Single-breath diffusing capacity for carbon monoxide (OLCO) and the volume of gas into which the single-breath of carbon monoxide and helium was diluted were not elevated. Smoking did not account for the results in group A but did seem to partially explain the decrease in FVC, FEV1, and FEF 25–75% in group B. Conclusions: Extreme obesity is associated with a reduction in ERV, FVC, FEV1, FRC, FEF 25–75% , and MVV. However, contrary to prior reports, OLCO is not elevated. These effects are only partially explained by smoking.
Phenomenon of color change in colored poly(vinyl chloride) compound

This paper addresses a phenomenon of color shift found during the development of a colored poly(vinyl chloride) (PVC) compound for exterior automotive application containing, among other pigments, red anthraquinone (C.I. Pigment Red 177) and titanium dioxide (TiO2). Color was found to shift about 2 points delta b* on a CIELAB scale from yellow to blue during the first one month and a half since the compound had been processed. The shift took place at the regular conditions: room temperature with no exposure to sunlight or heat.
Initial Treatment of Cystic Fibrosis Frequency of Transient Bulging Fontanel

Four infants with newly diagnosed cystic fibrosis developed a bulging anterior fontanel within days of starting enzyme replacement treatment. In the same time period, 41 hospitalized patients less than 1 year of age were diagnosed as having cystic fibrosis and treated, suggesting that increased intracranial pressure is common in this setting (9.7%). The clinical course of the four infants was similar: the bulging fontanel became apparent 1-6 days after initiation of pancreatic enzyme replacement and resolved within 1 week in three patients and within 4 months in the other patient. Two patients became mildly irritable. Computed cranial tomography and lumbar puncture were done in three patients, with completely normal findings except elevated cerebrospinal fluid pressure in two infants. There was no apparent difference in this treatment or clinical course before diagnosis between the four infants who developed a transient bulging fontanel compared with the overall group of cystic fibrosis patients.
A qualitative optimization technique for biophysical neuron models with many parameters

We present a novel computational technique that enables more efficient optimization of qualitative features in biophysical neural models. We extend the idea of multiple objective optimization for a single comparison modality (such as comparison of individual voltage traces) [1] into multiple modalities. For instance, features may be defined in terms of measurements from different experimental scenarios, and might include not only action potential spike shape characteristics (Cf. [1,2]) but also complex features such as the frequency response curve, and phase response curve (PRC). Multiple fuzzy feature modalities provide additional ways to distinguish solutions that might otherwise appear similarly fit in the restrictive view of a single modality and with crisp measures of fitness. An ill-posed optimization problem with many local minima typically arises from relative insensitivities of some parameters to features in a single modality, or parameter co-variation/modulation [2]. We use an implementation in the PyDSTool software [3] to demonstrate how the multi-modal approach can be prepared and embedded in conventional gradient-based or global optimization algorithms. Among other applications, we discuss the transformation over 25 model parameters of a Hodgkin-Huxley neuron model with a Type I PRC [4] to a Type II PRC, using a goal PRC shape and other periodic trajectory statistics as fuzzy objective modalities.
The student-run clinic: a new opportunity for psychiatric education.

Objective Student-run clinics are increasingly common in medical schools across the United States and may provide new opportunities for psychiatric education. This study investigates the educational impact of a novel behavioral health program focused on depressive disorders at a student-run clinic.
Evaluating hypermedia systems (panel)

Hypermedia systems provide online access to complex networks of information with the goal of making it easier to find and use information. To validate the utility of their systems, several researchers and system developers have attempted to collect evaluation data on the usability and effectiveness of their systems and the features in their systems. Because of the potential complexity of hypermedia systems and the information structures they may represent, a variety of evaluation measures and methods have been used. These trade off the need for timely feedback in the development of new technology, the difficulty of controlling one or two variables in systems with dozens or hundreds of components, and the goal of gaining an understanding of hypermedia systems.
The Inheritance of Egg Production and Hatchability in Turkeys

Abstract BREEDERS of turkeys are often disappointed in the small number of eggs laid by their hens and in the low hatchability of the eggs. The objectives of this study were to measure the degree of heritability of these two characters and to estimate the progress that breeders might expect to make by selecting for them in a breeding program. REVIEW OF LITERATURE There has been a limited amount of work to show that egg production is heritable in turkeys. Little or no work has been done, however, to show that hatchability is inherited. Breeders have long assumed that both characters are inherited since they are heritable in chickens. The investigations that have been made to date on egg production in turkeys have been concerned with measuring such factors as maturity, persistency, length of pauses, etc., which are known to affect egg production in chickens. Asmundson (1938) found that persistency, length . . .
Comparative Antiproliferative Activity in Vitro of Natural Interferons α and β for Diploid and Transformed Human Cells

Abstract The relative antiproliferative activity of natural interferons α and β was compared in 43 in vitro assays of 25 human cell lines or strains. After 120 hr of continuous exposure to 100 units/ml, interferon β produced >20% growth inhibition in 22 cells (88%), and interferon α produced 20% growth inhibition in 9 cells (36%). Only Daudi (Burkitt9s lymphoma) cells were consistently more inhibited by interferon α. In the other 24 human cells, the effect of interferon β was greater or equal to interferon α. Although no tissue specificity for interferon β was evident, interferon α generally had greater antiproliferative effects in cells of hematopoietic origin. The effect of interferon α was usually established by 72 hr with little further growth inhibition at 120 hr. Conversely, interferon β often had a greater antiproliferative effect at 120 than at 72 hr. These findings support the hypothesis that various interferons may differ in their biological, cell-regulatory, and clinical effects.
On reducing the rate of retransmission in time-varying channels

For data communications in time-varying channels such as wireless channels, the dynamic channel fluctuations often cause high frame-error rates. When the link layer detects that a frame is in error, conventionally, the frame is dropped and retransmission of the frame is requested. Based on the fact that the erroneous frames still contain useful information, several schemes have been proposed, such as packet combining and incremental redundancy, which retain and utilize the erroneous frames to improve retransmission performance. In this paper, we address two questions: 1) how much information is still useful in the erroneous frame; and 2) how to design a retransmission scheme to make efficient use of such information. We model this scenario (retransmission with an erroneous frame available at the receiver) as communication with side information at the receiver, and for a class of time-varying channels, the compound block interference channels, we derive with information-theoretic arguments the minimum information rate sufficient for retransmission to recover the erroneous frame. Motivated by the theoretical results, we propose an embedded channel coding/modulation structure together with a rate-adaptive retransmission scheme. Performance results indicate significant improvements over existing retransmission schemes in both additive white Gaussian noise and quasi-static Rayleigh fading channels.
Evidence for Orthologous Seed Weight Genes in Cowpea and Mung Bean Based on RFLP Mapping

A well saturated genomic map is a necessity for a breeding program based on marker assisted selection. To this end, we are developing genomic maps for cowpea (Vigna unguiculata 2N = 22) and mung bean (Vigna radiata 2N = 22) based on restriction fragment length polymorphism (RFLP) markers. Using these maps, we have located major quantitative trait loci (QTLs) for seed weight in both species. Two unlinked genomic regions in cowpea contained QTLs accounting for 52.7% of the variation for seed weight. In mung bean there were four unlinked genomic regions accounting for 49.7% of the variation for seed weight. In both cowpea and mung bean the genomic region with the greatest effect on seed weight spanned the same RFLP markers in the same linkage order. This suggests that the QTLs in this genomic region have remained conserved through evolution. This inference is supported by the observation that a significant interaction (i.e., epistasis) was detected between the QTL(s) in the conserved region and an unlinked RFLP marker locus in both species.
Volatile organic compounds as indicators of municipal solid waste leachate contamination

Abstract Due to their apparent mobility in many soil types and the analytical sensitivity of tests used for their detection, volatile organic compounds (VOC) may prove to be useful indicators of municipal solid waste (MSW) landfill leachate contamination. Data were collected from the analysis of leachates and from monitoring wells at sites where ground water was contaminated by MSW landfill leachates. Results of the leachate analyses show some volatiles to be ubiquitous in leachates. Commonly detected compounds include the priority pollutants toluene; methylene chloride; 1,1,2-trichloroethylene; 1,1-dichloroethane; ethylbenzene; benzene and trans-1,1-dichloroethylene. The non-priority pollutant parameters acetone, 2-propanol and xylene were also common in leachate.
Integration of Research and Practice: Innovations and Challenges in Social Work Programs

This paper presents results from an exploratory, mixed methods study on the integration of research and practice in the social work curriculum. A web-based survey was used to collect data from 184 social work research instructors. Seventy-eight percent of instructors reported that their programs integrated practice content in research courses, particularly at the BSW level. In contrast, about half of instructors reported that research content was infused in other courses, with less integration reported in MSW programs. Qualitative findings consistent with Siegel's typology for research and practice integration include the use of research activities as clinical interventions, as a way to shape interventions, and as a problem-solving process for practice. The implications for social work education are discussed.
Bribery or just desserts? Evidence on the influence of Congressional reproductive policy voting patterns on PAC contributions from exogenous variation in the sex mix of legislator offspring

Abstract Evidence on the relationship between political contributions and legislators’ voting behavior is marred by concerns about endogeneity in the estimation process. Using a legislator’s offspring sex mix as a truly exogenous variable, we employ an instrumental variable estimation procedure to predict the effect of voting behavior on political contributions. Following previous research, we find that a legislator’s proportion daughters has a significant effect on voting behavior for women’s issues, as measured by score in the “Congressional Record on Choice” issued by NARAL Pro-Choice America. In the second stage, we make a unique contribution by demonstrating a significant impact of exogenous voting behavior on PAC contributions, lending further credibility to the hypothesis that Political Action Committees respond to legislators’ voting patterns by “rewarding” political candidates that vote in line with the positions of the PAC, rather than affecting those same votes – at least in this high-profile policy domain.
Epileptiform propagation patterns mediated by NMDA and non-NMDA receptors in rat neocortex.

Summary: Purpose: The neocortex can generate various forms of epileptiform activity, including one that depends on N-methyl-D-aspartate (NMDA)-type glutamate receptors (NMDARs), and another dependent on non-NMDA-type (AMPA) glutamate receptors (AMPARs). Previous work in vitro suggests that both forms of activity are initiated by neurons of layer 5, but the spatial patterns of horizontal propagation have been studied only for the AMPAR form. We have tested the hypothesis that both types of epileptiform activity spread via common pathways in one cortical layer, suggesting that lamina-specific intervention might selectively interrupt both. Methods: Slices of rat somatosensory cortex were maintained in vitro and treated with the γ-aminobutyric acid type A (GABAA)-receptor antagonist picrotoxin. Single all-or-none epileptiform discharges were evoked with an electrical stimulus, and extracellular microelectrodes were used to track the vertical and lateral spread of the discharges. Results: In both high and low concentrations of picrotoxin, the non-NMDAR antagonist 6-cyano-7-nitroquinoxaline-2,3-dione (CNQX) completely blocked propagation, whereas the NMDAR antagonist D-2-amino-5-phosphonovaleric acid (DAPV) only shortened the duration of discharges. When extracellular [Mg2+] was reduced in the presence of picrotoxin and CNQX, NMDAR-dependent epileptiform discharges could be initiated. NMDAR-dependent discharges spread at about one fifth the conduction velocity of AMPAR-dependent events. Analysis of spatiotemporal field-potential patterns suggested that both NMDAR- and AMPAR-mediated propagation involved early activity in layers 5 and 6, followed by larger-amplitude activity in upper cortical layers along the path of propagation. Conclusions: Our results imply that a common pathway mediates the propagation of these two forms of epileptiform activity, and suggests that lamina-specific surgical intervention might maximize anticonvulsant effect while minimally disrupting cortical function.
Timing of ozone stress and resulting status of ribulose bisphosphate carboxylase/oxygenase and associated net photosynthesis

summary Experiments were conducted to determine how the timing of an exposure to ozone influenced the impact of the gas on ribulose- 1,5-bisphosphate carboxylase/oxygenase (Rubisco) throughout the life span of a designated leaf. Saplings of Populus maximowizii×trichocarpa NE 388 received 5-d exposures to O3 in growth chambers during and at the termination of presumed synthesis of Rubisco in a designated leaf. Ozone had no detectable impact on Rubisco activity or quantity when the exposure occurred during the time of increasing concentration of the protein in the leaf. When the concentration of Rubisco was near its peak, O3 induced a reduction in quantity and activity of Rubisco, but after cessation of the O3 stress, levels converged with those of the untreated tissue. When O3exposure occurred after full leaf expansion, minimal effects of the gas could be detected. When plants of hybrid popular or Raphanus sativus L. cv. Cherry Belle received chronic O3 treatment throughout the lifespan of the leaf, Rubisco activity and quantity declined more rapidly and never converged with values of untreated tissue. Studies of gas exchange revealed that changes in Rubisco were associated with a decline in net photosynthesis (A) and that these effects preceded the observed reduction in foliar conductance. CO2 response curves were measured periodically, and the initial slope (linear portion) of the curve, reflecting carboxylation capacity, declined more rapidly with leaf age in O3-treated than in untreated poplars. There was no effect of O3 on stomatal limitation to CO2, assimilation except for a slight increase during the last 2 wk of the 9-wk experiment. This supported the hypothesis that O3 effects on A were associated with CO2-fixing capability of the leaf.
Prognostic factors and preoperative radiation therapy associated with sphincter preservation in patients with resectable rectal cancer

Abstract Background This study evaluates the importance of patient and tumor factors, receipt of preoperative radiation therapy, and American Joint Committee on Cancer stage for sphincter preservation (SP) in patients with rectal cancer. Methods Age, sex, race, body mass index, tumor size, distance from the anal verge (DAV), differentiation, American Joint Committee on Cancer stage, and preoperative radiation were evaluated. The end point was continence versus colostomy. Comparison was done by logistic regression; data were presented as mean ± SEM; and significance was defined as P Results Factors independently associated with SP were greater DAV, body mass index (BMI) P Conclusions DAV remains the most important factor for prediction of SP in patients with rectal cancer. Preoperative tumor size and BMI were also independent factors. Preoperative radiation therapy may increase the chance of SP in patients with large tumors, increased BMI, or low rectal tumors.
Erythrocyte-bound immunoglobulin isotypes in dogs with immune-mediated hemolytic anemia: 54 cases (2001–2010)

Objective—To identify erythrocyte-bound immunoglobulin (Ig) isotypes in dogs with primary immune-mediated hemolytic anemia (IMHA). Design—Retrospective case series. Animals—54 dogs with IMHA. Procedures—Medical records of dogs with IMHA diagnosed between January 2001 and April 2010 were examined. Immunoglobulin isotype (tested via direct immunofluorescence by flow cytometry to identify erythrocyte-bound Ig), Hct, serum bilirubin concentration, presence of autoagglutination, degree of spherocytosis, duration of hospitalization, and 90-day outcome were recorded. Results—The Hct on admission was significantly lower in dogs with IgG and IgM isotypes bound to erythrocytes, compared with dogs with a single Ig isotype, and the degree of spherocytosis was greater in dogs with IgG and IgM bound to erythrocytes, compared with dogs that only had IgM. Dogs with only IgM were not more likely to have autoagglutination, compared with dogs that only had IgG on the erythrocyte surface. Although Ig isotype was not associat...
Tissue Injury from Exposure to Power Frequency Electrical Fields

The biological effects of electric fields is a topic that is gaining increasing attention. The spectrum of effects recognized in both the scientific and medical literature range from the subtle, such as altered gene expression, to the dramatic such as tissue destruction. In general, these effects are frequency-dependent. Ionizing fields with frequencies greater than 1021 Hz cause cellular damage by physicochemical processes very different from the damage resulting from power-frequency (50–60 Hz) electrical shock. Significant progress is being made in understanding these processes. The intent of this review is to focus on the problem of power-frequency electrical injury. Recent developments in understanding this important problem have led to the possibility of exciting new medical therapies.
Cognitive Assessment Trends in Home Health Care for Adults With Mild Stroke.

Objective This article describes current trends in cognitive assessment use for adults with mild stroke by home health practitioners in the United States. Method Participants were 56 home health occupational therapists and occupational therapy assistants. A self-administered survey about use of cognitive assessment tools in home health care and influences on their use was conducted. Results Ninety-six percent of participants assessed cognition in adults with mild stroke. Nonstandardized assessments were the most widely used method for evaluating cognition in the home health setting. Influences such as specialized training in specific assessments, confidence, and productivity requirements may have affected the practitioners' cognitive assessment decisions in home health care. Conclusion Although cognitive assessments are widely used in home health care, occupational therapy practitioners are selecting nonstandardized assessments most frequently to assess cognition.
Radiopharmaceuticals for Brain Imaging: The Technologist’s Perspective

This is the fourth article in a six-part series on new radiopharmaceuticals. Upon completion of this article, the nuclear medicine technologist will be able to describe the evolution of SPECT neuroimaging and discuss the current brain perfusion radiopharmaceutical characteristics.
Outbreak of Type C Botulism in Commercial Layer Chickens

SUMMARY This report describes an outbreak of type C botulism in two organic, free-range commercial layer farms in the Midwest. Hens affected were 64-wk-old Hy-Line brown hens and 34-wk-old Hy-Line brown hens owned by the same company, but housed on different premises, with approximately 20,000 birds per house. Mortality over the 2 wk of investigation was estimated to be up to 8% and 2.8%, respectively, with birds acting listless, lethargic, and depressed. Clinical signs consisted of progressive paralysis, and severely affected birds were moribund and laterally recumbent. Hens had ruffled feathers that easily epilated, with loss of muscular tone in the neck, tail, and wings. Hens had closed eyes and were reluctant to move. There were no significant gross or histopathologic lesions. Intestinal samples were submitted to the University of Pennsylvania Botulism Diagnostic Laboratory for real-time PCR and were positive for Clostridium botulinum organisms containing the Type C neurotoxin gene. Speculations on th...
What is the role of 3 T MRI in sports medicine? Revisiting the marriage after the honeymoon

The first 3 T MRI systems were introduced to clinical practice over a decade ago, and access to these systems has become increasingly available worldwide. Although they were first used for neurological imaging, several studies have demonstrated the abilities and potential advantages of 3 T systems over conventional 1.5 T systems for musculoskeletal disorders, including for their use in sports medicine.1 ,2 The introduction of 3 T MRI generated great expectations in the field, with hope for marked improvement in the diagnosis of musculoskeletal disorders.3 Tesla units are used to quantify the strength of a magnet field. In comparison to 1.5 T systems, 3 T MRI is characterised by increased MR signal with relatively less increase in background noise—thus having a higher signal-to-noise ratio (SNR).3 This advantage can be used to either decrease scanning time or improve spatial resolution. The increase in scan speed means increased patient comfort and throughput; increased resolution, especially in combination with surface coils, may prove advantageous for the visualisation of small structures such as the ligaments of the wrist or ankle.4 While several studies have shown similar or slightly increased diagnostic performance when using 3 T systems over 1.5 T in joint imaging using arthroscopy as a gold standard,1 ,5 ,6 there are no studies using the clinical gold standard of “How often has 3 T changed my treatment decision compared to 1.5 T MRI?” (figure 1). Figure 1 Direct …
Direct Evaluation of Polypeptide Partial Molar Volumes in Water Using Molecular Dynamics Simulations

Molecular simulations of a series of tri- and tetrapeptides with the sequences Gly-X-Gly and Gly-X-Y-Gly, where X and Y are neutral amino acid side chains, have been performed to characterize their volumetric properties in water at 300 K. The chains were terminated with both zwitterionic and neutral N-acetyl/amide functionalities to examine end group effects. The simulations accurately capture the experimental effects of side chain mutations and increasing peptide length, suggesting simulations can provide insight into the properties of unfolded oligopeptides and proteins. For the zwitterionic terminated chains, however, simulations exhibit a constant, lower volume than the experiment, suggesting that simulations over-predict electrostriction by the charged end groups. The simulation volumes are well-described by a group additivity based correlation, yielding excellent agreement between simulated side chain group volumes and the experiment. The accuracy of our simulations and fidelity of the group additiv...
Hybridization trends for main group elements and expanding the Bent's rule beyond carbon: more than electronegativity.

Trends in hybridization were systematically analyzed through the combination of DFT calculations with NBO analysis for the five elements X (X = B, C, N, O, and F) in 75 HnX–YHm compounds, where Y spans the groups 13–17 of the periods 2–4. This set of substrates probes the flexibility of the hybridization at five atoms X through variations in electronegativity, polarizability, and orbital size of Y. The results illustrate the scope and limitations of the Bent’s rule, the classic correlation between electronegativity and hybridization, commonly used in analyzing structural effects in carbon compounds. The rehybridization effects are larger for fluorine- and oxygen-bonds than they are in the similar bonds to carbon. For bonds with the larger elements Y of the lower periods, trends in orbital hybridization depend strongly on both electronegativity and orbital size. For charged species, the effects of substituent orbital size in the more polarizable bonds to heavier elements show a particularly strong response...
School Segregation and Its Discontents: Chaos and Community in Post–Civil Rights Memphis

Few policies have affected American society as deeply as those related to the landmark 1954 U.S. Supreme Court decision, Brown v. Board of Education. Now, 60 years later, segregation persists along race and class divisions. This case study analysis of a merger that took place between 2010 and 2013 in Memphis and Shelby County, Tennessee, one of the most politically contentious ones undertaken in the post–civil rights era, reveals a great deal about processes that sustain patterns of inequality. A new generation of Memphis leaders gives its perspective on education, social equality, and the future.
Genetic Testing and Health Insurance

This Article argues that our growing powers of genetic testing to identify individual health risks threaten to unravel the moral logic of health insurance. Some people are blessed with healthy genes and environments, while others are cursed with ill health. Spreading among groups the unknown risk that any particular individual or group will suffer disease and disability promotes values of social solidarity and mutual support by encouraging people, even if unwittingly, to share their fates with others.But increasingly reliable methods of genetic testing have private insurance providers clamoring for access to new types of predictive health information. The availability of more precise information about health risks that people did not choose and cannot control will make it possible for insurers to more finely disaggregate risk and premium levels among individuals. Smaller risk pools have serious costs: they diminish the incentive to participate; genetic risk classifications will put pressure on providers to deny coverage to those with the worst genetic luck; and fear of genetic discrimination will discourage individuals from reaping the health benefits of genetic testing. I argue that antidiscrimination legislation -- Congress's solution to these problems as of 2005 when this Article was written -- would cripple private insurance providers. I conclude that society should abandon the longstanding system of setting health insurance rates according to individual risk-factors, and, in its place, adopt a community rating system that balances free-market values with those of mutual trust and solidarity.