cssi/SciSciGPT-SciSciNet huggingface dataset:
Ribosomal ribonucleic acid-adenine (N 6 -) methylase of Escherichia coli strain B: ionic and substrate site requirements.

These investigations are concerned with the ionic and substrate-site requirements of ribosomal ribonucleic acid (rRNA)-adenine (N6-) methylase of Escherichia coli B. The methylase was essentially inactive in solutions of low ionic strength. The addition of MgCl2 (optimal at 5 mM) or; to a lesser degree, KCl (optimal at 45 mM) stimulated the rate of methylation; the combination of MgCl2 and KCl stimulated methylation to an extent equivalent to the sum of the stimulation of each acting alone. The extent of nonspecific binding of the methylase to rRNA decreased as the ionic strength of the solution increased. In the absence of ions, dimethylsulfoxide (DMSO), a nucleic acid denaturing agent, had little influence on the rate of methylation; however, DMSO plus KCl synergistically increased both the rate and the extent of methylation to a greater degree than the combination of Mg2+ plus K+. NH4+ was less effective than K+, and the divalent Mg2+ offered little stimulation. Monovalent anions (acetate, nitrate, and chloride) were equally effective, whereas divalent SO42− was decidedly inhibitory. The appropriate ionic milieu of mono- and divalent cations was required to provide the appropriate conformation of the rRNA and to facilitate specific interactions of the methylase and its recognition sites in the rRNA, while decreasing nonspecific ionic binding of the methylase to rRNA. DMSO may facilitate methylation by increasing the number of substrate sites exposed in single-stranded regions of the rRNA. Nonmethylatable rRNA species served as competitive inhibitors, whereas the polyanions deoxyribonucleic acid, transfer RNA, and polyadenylic acid were inactive. Micrococcus lysodeikticus and Bacillus subtilis rRNA, methylated by the methylase, each contained two distinct heptanucleotides containing newly synthesized 6-methyladenine moieties. The data are consistent with the view that E. coli strain B possesses two species of rRNA-adenine (N6-) methylases, each of which recognizes a specific adenine moiety in a unique pentapurine nucleotide sequence in a single-stranded region of rRNA.
Bacterial tolerances to metals and antibiotics in metal‐contaminated and reference streams

Anthropogenic-derived sources of selection are typically implicated as mechanisms for maintaining antibiotic resistance in the environment. Here we report an additional mechanism for maintaining antibiotic resistance in the environment through bacterial exposure to metals. Using a culture-independent approach, bacteria sampled along a gradient of metal contamination were more tolerant of antibiotics and metals compared to bacteria from a reference site. This evidence supports the hypothesis that metal contamination directly selects for metal tolerant bacteria while co-selecting for antibiotic tolerant bacteria. Additionally, to assess how antibiotic and metal tolerance may be transported through a stream network, we studied antibiotic and metal tolerance patterns over three months in bacteria collected from multiple stream microhabitats including the water column, biofilm, sediment and Corbicula fluminea (Asiatic clam) digestive tracts. Sediment bacteria were the most tolerant to antibiotics and metals, while bacteria from Corbicula were the least tolerant. Differences between microhabitats may be important for identifying reservoirs of resistance and for predicting how these genes are transferred and transported in metal-contaminated streams. Temporal dynamics were not directly correlated to a suite of physicochemical parameters, suggesting that tolerance patterns within microhabitats are linked to a complex interaction of the physicochemical characteristics of the stream.
The cyclin E promoter is activated by human cytomegalovirus 86-kDa immediate early protein.

Human cytomegalovirus (HCMV) activates cyclin E/Cdk2, which regulates cell cycle progression in G1and S phase of the cell cycle. HCMV activation of cyclin E/Cdk2 can be demonstrated in cells that are refractory to normal mitotic stimuli. This observation suggests that the virus has some means to overcome the stringent control on expression of cell cycle progression factors that is characteristic of cells in the G0 state. One of the mechanisms involved in activation of cyclin E/Cdk2 is the induction of cyclin E expression. We report here that HCMV induces cyclin E expression through a transcriptional mechanism. The cyclin E gene is activated by the HCMV 86-kDa immediate early gene product (IE86), which directly binds to nucleotide sequences within the cyclin E promoter. An IE86 DNA-binding mutant neither binds nor activates the cyclin E promoter. IE86-binding sites within the cyclin E promoter are required for IE86-mediated activation, and deletion of the IE86-binding site inhibits IE86 activation of the cyclin E promoter. We also demonstrate that mutation of the known E2F-binding sites in the cyclin E promoter does not block activation by HCMV or IE86. These data provide a molecular mechanism for HCMV induction of cyclin E and represent the first report of IE86 directly binding to a cellular promoter.
Biological guide to the eradication of communicable diseases: a realistic approach.

Abstract In a biological guide to the eradication of communicable diseases, the most effective available method is sanitary control. It must be coupled, however, with intensive health education, so that improved sanitary facilities will be acceptable to the population for which they are designed. It is mandatory that such methods not be contrary to the established cultural patterns. Physical and genetic means for the destruction of vectors of communicable diseases must urgently be developed. Continued application of the presently available chemical control should be subject to tightened surveillance on a global scale, to guard against the emergence of resistant mutants, to protect man from their toxic effects, and to prevent the destruction of flora and fauna. The application of presently available attenuated live viral vaccines should be expanded on a global scale. Means of development of comparable vaccines against diseases caused by nonviral agents should be explored. Antimicrobial drugs should be used against specific pathogens, never indiscriminately, and preferably under voluntary international control. International cooperation is mandatory in the studies of new pathogens, including those from outer space, and in the application against them of the above methods of control. Preservation of ecologic balance should be the primary concern of every eradication program.
A Note on Sonnet 2 of Brooks's the Children of the Poor

(2008). A Note on Sonnet 2 of Brooks's the Children of the Poor. The Explicator: Vol. 67, No. 1, pp. 51-53.
Polar body and pronucleus formation in the pig egg.

Pig eggs were recovered at known time intervals after insemination and ovulation. The number of sperm attached to the zona pellucida and the proportion of eggs fertilized increased continuously from two hours to 48 hours after insemination. Some eggs had cumulus cells until as late as 12 hours after ovulation. Sperm penetrated the eggs between six and 12 hours after ovulation and pronuclei persisted between eight and 12 hours after ovulation. The second meiotic division appeared to take place in a bulge from the cytoplasm. The second polar body was formed in this bulge and the female chromatin then migrated back into the cytoplasm.
Defining Family-Centered Rounds

Background: Physicians are required to provide safe, effective, and high-quality care that is patient-centered. Continuing to meet the educational needs of residents and medical students in the setting of patient-centered care will require developing new models for hospital “work rounds.” Family-centered rounds is a model of communicating and learning between the patient, family, medical professionals, and students on an academic, inpatient ward setting. Unfortunately, in the medical literature, there is no consensus on the definition of family-centered rounds. Summary: Despite the increased utilization of hospitalists and the recognition that bedside teaching has many benefits, bedside rounds are underutilized. In this article, we present a description of family-centered rounds that is supported by a review of the literature on bedside teaching, family-centered care, and interdisciplinary care. The key difference between family-centered rounds and traditional bedside teaching is the active participation ...
The Collective Identity of Marginal Peoples: The North Carolina Experience1

The conditions that make for the emergence and persistence of collective identity are examined on the basis of the history of two marginal groups in North Carolina. These are the Haliwa and the Sampson County Indians which constitute a total population of approximately 6000 persons. Historically their status has been ambiguous. The traditional focal points of group identity have been the churches and the schools. Today the churches remain but the schools are gone. A new emphasis presently is being placed on associations, coalitions, and pageants as structures and expressions of Indian identity.
Opposite effects of fear conditioning and extinction on dendritic spine remodelling

It is generally believed that fear extinction is a form of new learning that inhibits rather than erases previously acquired fear memories. Although this view has gained much support from behavioural and electrophysiological studies, the hypothesis that extinction causes the partial erasure of fear memories remains viable. Using transcranial two-photon microscopy, we investigated how neural circuits are modified by fear learning and extinction by examining the formation and elimination of postsynaptic dendritic spines of layer-V pyramidal neurons in the mouse frontal association cortex. Here we show that fear conditioning by pairing an auditory cue with a footshock increases the rate of spine elimination. By contrast, fear extinction by repeated presentation of the same auditory cue without a footshock increases the rate of spine formation. The degrees of spine remodelling induced by fear conditioning and extinction strongly correlate with the expression and extinction of conditioned fear responses, respectively. Notably, spine elimination and formation induced by fear conditioning and extinction occur on the same dendritic branches in a cue- and location-specific manner: cue-specific extinction causes formation of dendritic spines within a distance of two micrometres from spines that were eliminated after fear conditioning. Furthermore, reconditioning preferentially induces elimination of dendritic spines that were formed after extinction. Thus, within vastly complex neuronal networks, fear conditioning, extinction and reconditioning lead to opposing changes at the level of individual synapses. These findings also suggest that fear memory traces are partially erased after extinction.
Structural control of Fano resonances in semiconductor heterostructures

Abstract Structural control of quantum interference in the optical intrasubband absorption spectrum of GaAs/AlGaAs multi-quantum wells is investigated theoretically. Our study shows that pronounced Fano resonances are in general difficult to obtain in quantum well heterostructures, with a presence of distinct Fano resonance features being the exception rather than the rule. Guided by an analogy to Young’s double-slit experiment, we design increasingly improved structures to display Fano resonances. Best results are achieved in structures where there is strong overlap between the ground-state wavefunction and scattering states associated with the uncoupled continuum. Alternatively one may use ionization via two or more resonances. In this case, resonances should not be separated by more than 25 meV to give significant effects. Moreover, we show that resonance features may also be induced without potential barriers to a continuum merely via orthogonality between bound and excited states.
The Personality Assessment Inventory: Clinical Utility, Psychometric Properties, and Normative Data for Bariatric Surgery Candidates

The Personality Assessment Inventory (PAI), an overall measure of personality and psychopathology, features a number of dimensions that may be useful in the psychological assessment of bariatric surgery candidates. However, its clinical utility is limited because psychometric properties of the PAI with bariatric surgery candidates have never been evaluated, and normative data for this population have never been published. We examined the psychometric properties and clinical utility of the PAI with a large sample of bariatric surgery candidates (n = 546) presenting for evaluation in an urban medical center. Internal consistency reliability analyses were performed on the PAI full scales and subscales. Exploratory factor analysis using principal components analysis with oblique rotation was performed and the results compared with community, clinical, and medical samples. Normative data and scale elevation frequencies for the bariatric sample are presented. Alpha coefficients and mean interitem correlations were acceptable and similar to the test standardization samples. Factor analyses supported the consistency of the underlying factor structure with bariatric surgery candidates and also revealed a factor for warmth and social support. Normative data indicate that overall bariatric surgery candidates appear quite similar to the community standardization sample. Sixteen percent of candidates reported significant (T ≥ 70) somatic complaints, consistent with the greater health problems in this sample. Our findings support the clinical utility of the PAI in the psychological assessment of bariatric surgery candidates. The availability of PAI normative data and profile elevation statistics will help to facilitate clinical interpretation and inform treatment recommendations for candidates undergoing bariatric surgery.
TOTAL QUALITY MANAGEMENT: A LITERATURE REVIEW AND AN AGENDA FOR FUTURE RESEARCH

Total quality management (TQM) is a revolutionary approach to effective management. The research in TQM has emerged from practical needs of organizations embracing this philosophy, and the literature is mostly conceptual and practitioner-oriented. There is a lack of sound theoretical framework classifying past efforts and guiding future research. To fill the void, a study of the published TQM literature is undertaken. A review, classification, and analysis of the research in TQM spanning the last two decades is presented. A total of 226 TQM-related articles are identified from 44 refereed management journals published from 1970 to 1993. These articles are then classified and analyzed using the following two-dimensional scheme: (1) article orientation (conceptual, case study, empirical, analytical, simulation, and overview) and (2) article focus using the Malcolm Baldrige National Quality Award criteria. The analysis of the literature presents pertinent developments in each of the seven criteria. In addition, it provides future research directions as well as a ready reference of the TQM literature. The suggestions for research should guide future developments in the TQM field and help transform it into a formal discipline.
A report card on outcomes for surgically treated gastrointestinal cancers: are we improving?

Introduction. Longitudinal analyses of cancer registries provide an opportunity for population-based explanations of epidemiology and survival-related outcomes. This study used two population-based data sets to report on nine surgery-related cancers over the past three decades. Materials and methods. Using the SEER cancer database (1973-1999), all patients (>18 years old) with adenocarcinoma of esophagus, gastric, biliary system, pancreas, small bowel, colon, rectum; esophageal squamous cell carcinoma (ESC), or hepatocellular (HCC) carcinoma (n = 379,640) were analyzed. Changes in incidence rates, stage at diagnosis, and 5-year cancer and stage-specific survivals were determined. A separate database, the California inpatient database (1990-2000), was concurrently used to evaluate inpatient mortality after surgical resection (n = 34,057). Results. Incidence rates increased for three cancers (esophageal, HCC, small bowel); decreased for three (rectal, gastric, ESC); and stayed constant for three (biliary, pancreatic, colon). More patients presented with local/regional disease in the 1990s versus 1970s for eight tumors (except small bowel, P < 0.05). Five-year overall survival improved for all but small bowel (P < 0.05); and local stage survival was improved for all except small bowel and biliary (P < 0.05). Finally, inpatient mortality rates improved significantly for liver, esophageal, pancreatic, and gastric resections (P < 0.05) over the past decade. Conclusions. For these nine surgically treated cancers, we are detecting disease at earlier and therefore more treatable stages, and surgical care and outcomes also appear to have improved. Continued reexamination of longitudinal trends of surgically relevant outcomes is important for future improvement of surgical care.
Immunological responses to injury and grafting in the central nervous system of nonhuman primates.

Abstract Allogeneic transplantation for the therapy of human Parkinson’s disease is being considered as a viable approach at several clinical centers worldwide. As an attempt to understand the basic biology of central nervous system (CNS) transplantation, our laboratory has developed an experimental nonhuman primate model for human Parkinson’s disease and carried out preliminary studies directed at evaluating the potential pathology at the graft site. In addition, studies have been conducted to examine whether such transplantation procedures lead to specific and/or nonspecific immunologic sensitization of the host or results in generalized immunosuppression. Groups of rhesus macaques ( Macaca mulatta ) were either controls operated ( n = 6), autografted with adrenal medullary and peripheral nerve tissue ( n = 3), or allografted with fetal mesencephalic tissue ( n = 6). Immunohistological studies demonstrated the presence of mononuclear cell infiltrates as early as 1 wk and up to 1 yr postoperatively, although the frequency of the infiltrating cells declined with time. The infiltrates consisted of variable numbers of cells which express CD2+, CD3+, CD4+, CD8+, CD19+, CD22+, CD25+, and CD68+. There appeared to be no difference in the frequency, kinetics, or phenotype of the infiltrating cells in operative controls compared with recipients of auto- or allografts. Tissue sections obtained postoperatively showed low levels of major histocompatibility complex (MHC) Class I antigens and no detectable level of MHC-Class II antigens in neural tissue. A small aliquot of tissue from the operative site was placed in vitro with media containing interleukin-2 (IL-2), which led to the exudation and growth of mononuclear cells that were predominantly CD4+ cells. Phenotypic studies of peripheral blood mononuclear cells (PBMC) from operative controls, auto- and allograft recipient monkeys performed at varying time periods postoperatively failed to show differences in the frequencies of subsets of T-cells, B-cells, NK-cells, or monocytes. Studies on aliquots of the same PBMC failed to show major functional differences in NK-cells, LAK cells, or response to polyclonal mitogens. Finally, recipients of allogeneic mesencephalic grafts failed to show evidence of donor-specific humoral or cellular sensitization. These data indicate that transplantation of autograft adrenal or allograft fetal mesencephalic tissues in the CNS of nonhuman primate did not induce detectable donor-specific sensitization nor nonspecific immunosuppression.
Infectious Agents of Food- and Water-Borne Illnesses

Food- and water-borne infections have afflicted mankind since the earliest days of human development and preceded the emergence of civilization. Despite current knowledge of microbial pathogenicity, modern methods of food production and rigorous industrial hygiene, these infections are still commonplace and exact significant health and economic tolls on human populations in all parts of the globe. This review uses data derived from new surveillance networks to survey the current epidemiology of bacterial, protozoan and viral pathogens transmitted by food and water. In addition, we will discuss clinical features of human disease caused by pathogens of current and emerging relevance.
Papers: Local feedback stabilization of large interconnected power systems in emergencies

On-line stabilization of the large interconnected power system poses problems which are unusual among large systems. The system can lose stability in 2-3 s or sooner-yet, even a simplified model of it consists of hundreds or thousands of state variables. Hence, a full state identification or estimation and a dynamic control utilizing the complete system dynamics is computationally out of the question. In fact, of necessity, any centralized action must be quite limited. This leaves the challenging task of using local information to achieve system-wide stabilization. Control is also limited by practical considerations to short pulses of positive or negative power of fixed magnitude. A nonlinear transformation which maps the conventional state space of the power system into a new observation decoupled state space is introduced and shown to be a homeomorphism. This state space has the property that its components can be measured piecemeal in local groups and its origin is the unique stable equilibrium point of the power system when one exists. It is then shown that a feedback control, based on such local information, is capable of assuring system-wide approach to the stable equilibrium point. The existence of a stability region for this local feedback control is also shown.
Polytelluride compounds containing distorted nets of tellurium

The propensity of solid state polytelluride compounds to form structures with extended square nets of tellurium and the physicochemical properties of these nets is discussed in view of recent results showing that these square nets of tellurium are in fact average structures. The real structures are strongly modulated, giving rise to patterns within these nets that involve polytelluride oligomers. The patterns are dictated by the average electron-count on the tellurium atoms and often, sophisticated crystallographic techniques (electron diffraction, superstructure, and super spacegroup approaches) are required to elucidate them. In this account we discuss the structural peculiarities observed in KCuCeTe4, RbCuCeTe4, Na0.8Ag1.2CeTe4, K2.5Ag4.5Ce2Te9, K2.5Ag4.5La2Te9, Cu0.66EuTe2, KCu2EuTe4, Na0.2Ag2.8EuTe4, and K0.65Ag2Eu1.35Te4.
Environmental Intervention in Carryout Restaurants Increases Sales of Healthy Menu Items in a Low-Income Urban Setting

Abstract Purpose. To investigate how a pilot environmental intervention changed food sales patterns in carryout restaurants. Design. Quasi-experimental. Setting. Low-income neighborhoods of Baltimore, Maryland. Subjects. Seven carryouts (three intervention, four comparison). Intervention. Phase 1, menu board revision and healthy menu labeling; phase 2, increase of healthy sides and beverages; and phase 3, promotion of cheaper and healthier combination meals. Measures. Weekly handwritten menu orders collected to assess changes in the proportion of units sold and revenue of healthy items (entree, sides and beverages, and combined). Analysis. Logistic and Poisson regression models with generalized estimating equations. Results. In the intervention group, odds for healthy entree units and odds for healthy side and beverage units sold significantly increased in phases 2 and 3; odds for healthy entree revenue significantly increased in phase 1 (odds ratio [OR] 1.16, 95% confidence interval [CI] 1.08–1.26), phas...
Atlantoaxial fusion: a biomechanical analysis of two C1–C2 fusion techniques

Abstract Background context Different atlantoaxial fusion techniques are used for instability. Transarticular screws are biomechanically superior to wiring techniques and equivalent to C1 lateral mass to C2 pedicle (C1LM-C2P) fixation. Recently, C1 lateral mass to C2 laminar (C1LM-C2L) fixation has been shown to have flexibility similar to C1LM-C2P fixation in flexion, extension, lateral bending, and axial rotation. Purpose Compare the stiffness of C1LM-C2P with C1LM-C2L screw rod fixation. Study design In vitro biomechanical study. Outcome measures Stiffness in flexion/extension, lateral bending, axial rotation, and anterior-posterior (AP) translation. Methods Eight fresh-frozen human cadaveric cervical spines (C1–C3) were tested intact and, after a type II odontoid fracture, were instrumented and tested with two fixation constructs: C1LM-C2P screws and C1LM-C2L screws. The testing involved flexion, extension, lateral bending, AP translation, and axial rotation. Stiffness was measured and compared with a repeated-measures analysis. Results C1LM-C2P was significantly stiffer than the intact in AP translation (p Conclusion C1LM-C2P fixation is equivalent to C1LM-C2L fixation in flexion/extension and AP translation and superior in lateral bending and axial rotation.
Abstract 2356: Establishment of HPV-positive and HPV-negative head and neck cancer tumorgrafts directly from patient biopsies

Proceedings: AACR 103rd Annual Meeting 2012‐‐ Mar 31‐Apr 4, 2012; Chicago, IL PURPOSE: To develop a clinically relevant model system to study head and neck squamous cell carcinoma (HNSCC), we have established a direct from patient, tumorgraft model of both Human Papillomavirus (HPV)-positive and HPV-negative cancers and have performed initial therapeutic response characterization. METHODS: Following IRB approval, patients with newly diagnosed or recurrent HNSCC were consented for donation of tumor at the time of surgical procedure. Tissue from either the primary site or a lymph node metastasis was obtained, washed in antibiotic rich media, manually disaggregated, and subcutaneously implanted into mice (NOD.Cg-Prkdc scid Il2rgtm1Wjl/SzJ) for initial tumorgraft establishment. Subsequent mouse-to-mouse passages were performed and formalin-fixed/paraffin embedded as well as flash frozen tissue was harvested for subsequent molecular analyses. On the basis of hematoxaylin/eosin staining, patient tumor and primary tumorgraft were compared by a pathologist. To assess tumor growth rates and response to therapy (radiation, cisplatin, cetuximab) tumors were implanted into athymic nude mice and tumor growth curves monitored with twice-weekly tumor measurement. RESULTS: Patient demographics demonstrate a diverse group of donors with significant variations in tobacco and alcohol history, age, HPV status, and prior therapy. To date, tumorgraft establishment has been successful in 60% of cases (18/30). Primary tumor and tumorgraft showed high pathology correlation for differentiation status (well, moderately or poorly differentiated, Fisher Exact probability test p<0.0001). Significant variation in tumorgraft doubling time was observed with the most rapid of 4.9 days ranging up to 24.2 days. Increased tumor doubling time was noted following treatment with radiation (mean doubling time: 140% of control, range: 80% - 230%), cisplatin (mean: 150%, range: 91% - 180%), and cetuximab (mean: 240%, range: 81% - 390%). CONCLUSIONS: We have established a robust tumorgraft model system for investigating HPV-positive and HPV-negative HNSCC. Characterization to date shows significant heterogeneity of tumor types and therapeutic response paralleling that observed in clinical populations. These human tumorgrafts provide a powerful resource for investigating mechanisms of therapeutic response and preclinical testing of radiation and/or chemotherapy regimens. Citation Format: {Authors}. {Abstract title} [abstract]. In: Proceedings of the 103rd Annual Meeting of the American Association for Cancer Research; 2012 Mar 31-Apr 4; Chicago, IL. Philadelphia (PA): AACR; Cancer Res 2012;72(8 Suppl):Abstract nr 2356. doi:1538-7445.AM2012-2356
A spatially selective opposed-loop surface coil

Abstract We describe a variation of the conventional surface coil for use in large-sample NMR. It consists of two concentric and coplanar circular loops of wire with different diameters and possibly different numbers of turns, and with currents flowing in opposite directions. The ratio of currents may be chosen so that the field near the center of the coil is zero, resulting in a region at some distance from the coil in which the radiofrequency field intensity is uniform. A parallel winding scheme is described which allows operation at high frequencies. A 5 cm overall diameter opposed-loop coil was built to operate at 80 MHz and exhibited an axial maximum in sensitivity between 1.5 and 2 cm from the plane of the coil.
Writing, designing, and processing information in the Darwin information typing architecture (DITA)

The Darwin Information Typing Architecture is an XML architecture for producing and reusing technical information. This tutorial covers the basics of topic-oriented writing, and then proceeds to the specifics of topic structures in DITA, and the DITA information types.After covering how to create information in DITA, the tutorial will cover how to use the architecture to create specialized topic types and transforms.The tutorial assumes you have some familiarity with topic-oriented writing and information types. Familiarity with XML DTD syntax, and with XSLT, will be helpful but not essential.Bring laptops with an XML editor, parser, XSLT interpreter, and the DITA package installed. At minimum, have a simple text editor, plus the DITA package, plus Apache's Xalan and Xerces installed.You can get the DITA package from its developerWorks home: http://www.ibm.com/developerworks/xml/library/x-dita1
Bott periodicity and calculus of Euler classes on spheres

A variety of computations regarding the Euler class group E(An,An) and the Grothendieck group K0(An) of the algebraic sphere Spec(An) is done. The Euler class of the algebraic tangent bundle on Spec(An) is computed. It is also investigated whether every element in the Euler class group E(An,An) is the Euler class of a projective An module of rank n.
Concurrent reflectance imaging and microdialysis in the freely behaving cat

We present a method to perform simultaneous microdialysis with light reflectance imaging of neural activity in a discrete brain region of the freely behaving animal. We applied this method to the dorsal hippocampus of freely behaving cats to (1) measure extracellular glutamate and reflectance variations across a sleep-waking cycle, (2) assess spatially coherent neural activity changes accompanying local perfusion of cocaine and (3) measure local changes in cell volume induced by infusion of hyper- and hypo-osmotic solutions. Higher extracellular glutamate concentrations corresponded to higher imaged neural activity. Sequential images showed that cocaine perfusion elicited a propagating reflectance change as cocaine reached the tissue. Microperfusion of hypo-osmotic solution ( - 100 mOsm), which increases cell volume, decreased reflectance. Microperfusion of hyperosmotic sucrose solutions, which reduce cell volume, increased reflectance in a dose-dependent manner. The data indicate that reflectance imaging can measure changes in cell volume, and could, thus, measure neural activity through activity/cell volume corollaries. Combining microdialysis and optical imaging enables investigation of the neurochemical bases of spontaneous neural activity patterns within discrete brain nuclei.
STUDIES OF PROTEIN AND BOUND COENZYME FLUORESCENCE OF LACTATE DEHYDROGENASES.

Abstract 1. 1. The protein fluorescence polarization and the quantum yield of fluorescence per mole of tryptophan has been determined for the heart (H) and muscle (M) types of lactate dehydrogenases from beef and chicken. These quantum yields are among the highest yet reported for proteins. The M types have yields than the H forms. 2. 2. The qunatum yield of fluorescence and the fluorescence polarization on binding of NADH and the reduced 3-acetylpyridine analogue (AcPyADH) of NADH were determined for each of the enzymes and reveal an increase of quatum yield on binding of NADH of 1.3–2.6, and on binding of AcPyADH of 20–30-fold. 3. 3. The absolute quantum yield of fluorescence of free AcPyADH was determined and found to be 1.1%, as compared to 3% for NADH. 4. 4. The quenching of protein fluorescence on binding of coenzyme was found to be non-linear and could not be completely quenched by bound coenzyme. From these observations it has been concluded that the coenzymes may be found closely to each other and interact only with certain tryptophan residues in the enzyme. 5. 5. A method is presented for the combined fluoremetric determination of the number of coenzyme binding sites and the coenzyme dissociation constant. For all of the enzymes, the number of binding sites was 3–4 and the coenzyme dissociation constants approx. 10 −7 M.
Intrafamilial relations of cardiovascular disease risk factors in African-Americans: longitudinal results from DC SCAN.

Abstract Background. Few studies have examined intrafamilial patterns of cardiovascular disease (CVD) risk factors in African-American families or identified potential influences on these patterns. This study examines the effects of age and sex of child on correlations between siblings during childhood as well as between mothers and their offspring in African-American families at two points in time. Methods. CVD risk factors were assessed in a sample of 267 pairs of African-American siblings and their mothers. One hundred nine of these families were selected for a second assessment of CVD risk factors approximately 28 months later. Results. Older siblings had significantly greater correlations than younger siblings with mothers' low-density lipoproteins ( r = 0.61 versus r = 0.43 for older and younger siblings, respectively), apolipoprotein A-I ( r = 0.46 versus r = 0.16), and lipoprotein (a) ( r = 0.71 versus r = 0.34). Correlations between female siblings were significantly higher than between male siblings for total cholesterol ( r = 0.74 versus r = 0.18 for female versus male siblings), triglycerides ( r = 0.56 versus r = 0.05), and apolipoprotein B ( r = 0.72 versus r = 0.31); they were also higher between female siblings than between mixed-sex siblings for measures of adiposity ( r = 0.46 versus r = 0.19) and total cholesterol ( r = 0.74 versus r = 0.27). Conclusions. Significant intrafamilial correlations for African-American children were influenced by both age and sex of siblings, reflecting potential genetic and environmental influences. Assessing family patterns of CVD risk factors in high-risk populations may assist in the early identification of children who can benefit most from intervention.
Acidified Sodium Chlorite as an Alternative to Chlorine for Elimination of Salmonella on Alfalfa Seeds

The health and environmental hazard associated with the use of chlorine for food processing has been documented previously. This study was conducted to determine if acidified sodium chlorite (ASC) could be used to replace calcium hypochlorite (Ca[OCl](2)) for disinfection of alfalfa seeds. Contaminated seeds containing approximately 1.5 x 10(7) CFU/g of Salmonella were treated with ASC or Ca(OCl)(2) at different concentrations and for different periods of time. Results showed that the efficacy of ASC and Ca(OCl)(2) for elimination of Salmonella on contaminated seeds could be improved greatly by extending the treatment time from the traditional 15 to 45 min. Treatment of seeds with 800 ppm of ASC for 45 min reduced the number of Salmonella by 3.9 log units, approximately 1.2 log units higher than that treated with 20000 ppm of Ca(OCl)(2). Treatment of seeds with a lower concentration (100 to 400 ppm) of ASC for 45 min reduced the number of Salmonella by 1.3 to 2.2 log units. Soaking alfalfa seeds in 800 ppm of ASC for 45 min did not affect seed germination. However, soaking seeds in 20000 ppm of Ca(OCl)(2) for 45 min reduced seed germination by 20%. Unlike Ca(OCl)(2), antimicrobial efficiency of ASC was not affected by pre-exposure to alfalfa seeds. Data presented also showed that Salmonella on newly inoculated seeds that had been stored at 4 degrees C for less than 7 d were more sensitive to sanitizer treatment than those on seeds that had been stored for 4 wk or longer.
Characterization of alanine-rich peptides, Ac-(AAKAA)n-GY-NH2 (n = 1-4), using vibrational circular dichroism and Fourier transform infrared. Conformational determination and thermal unfolding.

Vibrational circular dichroism (VCD) and Fourier transform IR (FTIR) were measured for a series of short alanine-based peptides having the general formula Ac-(AAKAA)n-GY−NH2 (n = 1−4) from 5 to 50 ...
Revised ThO2‐Nb2O5 Phase Diagram

The phase equilibrium diagram of the system ThO2-Nb2O was redetermined near the composition Th2Nb2O9. This phase was found to melt incongruenlly at 1362°C, with a eutectic temperature at ∼1350°C. The peritectic and eutectic compositions must occur between 60 and ∼64 mol % ThO2. From single crystal and powder X-ray diffraction data, Th2 Nb2O9 was found to have a primitive monoclinic unit cell with a = 6.711(1), b = 25.254(5), c=7.757(1)×10−1nm, β=90.46 (1)°.
Algorithms for static stackelberg games with linear costs and polyhedra constraints

Three algorithms for solving the static Stackelberg game with two decision makers, linear costs and polyhedra constraints are presented. The nonconvexity of the Reaction set of the Follower is a major source of difficulty in solving such problems. The algorithms presented are able to bypass this difficulty and find the solution in a finite number of iterations.
Purification and biochemical characterization of a mouse submandibular sialomucin

Abstract A sialomucin from the mouse submandibular gland was isolated and purified by a protocol involving Sephacryl S-200 chromatography, acidic dialysis, and preparative, poly(acrylamide)-gel electrophoresis. The mucus glycoprotein was judged to be free from contaminants by analytical and sodium dodecyl sulfate-poly(acrylamide)-gel electrophoresis, isoelectric focusing, immunoelectrophoresis, an immunodiffusion when made visible by Stains-all, periodic acid-Schiff reagent, and Coomassie Blue. The carbohydrate portion constituted 81% of the weight of the mucus glycoprotein, and was composed of 2-acetamido-2-deoxy- d -glucose, 2-acetamido-2-deoxy d -galactose, sialic acid, d -galactose, and d -mannose. Neither l -fucose nor sulfate was detected. The aliphatic amino acids constituted 60% of the protein core. The sialomucin has an apparent mol. wt. of 140,000 by sodium dodecyl sulfate-gel electrophoresis, and a pl of 2.77–3.63 by isoelectric focusing.
BMPER regulates cardiomyocyte size and vessel density in vivo.

Abstract Background BMPER, an orthologue of Drosophila melanogaster Crossveinless-2, is a secreted factor that regulates bone morphogenetic protein activity in endothelial cell precursors and during early cardiomyocyte differentiation. Although previously described in the heart, the role of BMPER in cardiac development and function remain unknown. Methods BMPER-deficient hearts were phenotyped histologically and functionally using echocardiography and Doppler analysis. Since BMPER −/− mice die perinatally, adult BMPER +/− mice were challenged to pressure-overload-induced cardiac hypertrophy and hindlimb ischemia to determine changes in angiogenesis and regulation of cardiomyocyte size. Results We identify for the first time the cardiac phenotype associated with BMPER haploinsufficiency. BMPER messenger RNA and protein are present in the heart during cardiac development through at least E14.5 but is lost by E18.5. BMPER +/− ventricles are thinner and less compact than sibling wild-type hearts. In the adult, BMPER +/− hearts present with decreased anterior and posterior wall thickness, decreased cardiomyocyte size and an increase in cardiac vessel density. Despite these changes, BMPER +/− mice respond to pressure-overload-induced cardiac hypertrophy challenge largely to the same extent as wild-type mice. Conclusion BMPER appears to play a role in regulating both vessel density and cardiac development in vivo; however, BMPER haploinsufficiency does not result in marked effects on cardiac function or adaptation to pressure overload hypertrophy.
Error probabilities for Rician fading multichannel reception of binary and n -ary signals

Performance characteristics are derived for two different forms of multireceivers (the coherent and noncoherent) which are used with binary and N -ary signaling through the Rician fading multichannel. The coherent multireceiver is capable of perfectly measuring the channel amplitudes and phases whereas, at the other extreme, the noncoherent multireceiver implies a receiver which requires no channel measurement whatsoever. The multichannel model presumes that each transmission mode supports a specular or fixed component and a random or scatter component which fades according to the Rayleigh distribution. Heretofore, performance analyses of multichannel links have assumed that the fading obeys the Rayleigh law. This multichannel model is sufficiently general to include four practical types: the Rician and the Rayleigh fading multichannels, multichannels whose propagation modes do not fade, and those which simultaneously contain Rician and Rayleigh fading propagation paths or the so called mixed-mode multichannel. Error probabilities are graphically illustrated and compared for various multichannel models. It is found that the effectiveness of multichannel reception is highly dependent on the strength of the specular channel component relative to the mean squared value of the random channel component. In particular, multichannel reception is more effective when applied to the completely random multichannel. For special cases the error-rate expressions reduce to well-known results.
Cross-Over Trial of Treatment for Bradycardia Attributed to Gastroesophageal Reflux in Preterm Infants

Objective To determine whether anti-reflux medications reduce bradycardia episodes attributed to clinically suspected gastroesophageal reflux (GER). Study design We conducted a masked trial comparing metoclopramide, 0.2 mg/kg/dose q 6 hours, and ranitidine, 2 mg/kg/dose q 8 hours, with saline placebo. Each infant served as his own control. Preterm infants having >3 bradycardia episodes per 2 days were eligible if the clinician intended to begin anti-reflux medications for bradycardia attributed to GER. Results The mean (SD) birth weight was 1238 (394) g and gestational age was 29 (3) weeks. Eighteen infants were enrolled at 35 (22) days of age. There were 4.6 (3.1) and 3.6 (2.7) bradycardia episodes per day in the drug and placebo periods, respectively. The mean difference (drug minus placebo) was 0.94 (95% CI, 0.04 to 1.95) ( P = .04 by t test). There was a decrease in bradycardia episodes over time ( P Conclusions Anti-reflux medications did not reduce, and may have increased, bradycardia episodes in preterm infants with GER. Because there was an improvement of bradycardia episodes over time, unrelated to treatment, unmasked therapeutic trials of medications are likely to lead to misleading conclusions.
Urinary Bladder Herniation through a Vaginal Tear in a Rottweiller with Dystocia

Summary A four-year old female Rottweiler presented with a 34-hour history of dystocia. Physical examination revealed a purple-black, fluid-filled sac protruding from vulva and suspended by a similar colored stalk. Digital vaginal examination indicated that the stalk of tissue extended up into the cervix and beyond. Due to the grossly necrotic appearance, the stalk of tissue was ligated, and the sac was removed. Three puppies were delivered vaginally, but a subsequent caesarian section was required due to uterine inertia likely secondary to exhaustion. Three more live puppies were delivered via the c-section. Further abdominal exploration revealed a tear in the left vaginal wall, one ligated ureter, and the second ureter free at its distal end and leaking urine into the abdomen. The surgical findings indicated that the bladder, ureters, and urethra had herniated through the vaginal tear and prolapsed through the vulva.
Reactions of [14C]-3,4-Dichloroisocoumarin with Subunits of Pituitary and Spleen Multicatalytic Proteinase Complexes (Proteasomes)†

Exposure to [14C]-3,4-dichloroisocoumarin (DCI) of multicatalytic proteinase complexes (MPC) isolated from bovine pituitary and spleen leads to label incorporation into several beta-type subunits, to rapid inactivation of the chymotrypsin-like (ChT-L) activity, and to a slower inactivation of other activities of the MPC. The pituitary and spleen MPCs differ in that the first contains almost exclusively the X, Y, and Z subunits, whereas in the latter these subunits are largely replaced by LMP2, LMP7, and MECL1. Preincubation with two peptidyl aledhyde inhibitors of the ChT-L activity protected the X subunit in the pituitary MPC and unexpectedly the LMP2 subunit in the spleen MPC from label incorporation, despite the greater amino acid sequence homology of the LMP7 subunit to that of the X subunit. Losses in the yield of amino acids in both subunits, shown by amino acid sequencing, and lability of the DCI-protein bond indicated formation of an acyl derivative by reaction of DCI with the threonine OH group. Brief exposure to [14C]-DCI led to preferential incorporation of label into the LMP2 and X subunits, consistent with the high inactivation rate constants of the ChT-L activity. Z-LLF-CHO, an inhibitor of ChT-L activity, but not Z-GPFL-CHO, an inhibitor of the branched chain amino acid preferring component, prevented incorporation of radioactivity into the X subunits, whereas both inhibitors prevented label incorporation into LMP2, indicating differences in susceptibility to inhibition between the two components. These and other data are consistent with involvement of the X and LMP2 subunits in expression of the ChT-L activity in the pituitary and spleen MPC, respectively, and suggest the catalytic functions of two other beta-subunits.
Alineación entre las evaluaciones externas y los estándares académicos: El Caso de la Prueba Saber de Matemáticas en Colombia.

In this study the concept of alignment is analyzed by presenting the results of a study that examines the degree of alignment between a standardized mathematics assessment and a set of academic standards. The alignment was examined using the Webb model and the results suggest that the degree of alignment between standardized assessments and academic content standards is not the most appropriate and therefore the results should be interpreted with great caution and stakeholders must be very careful with the type of decisions that are made based on the results of these types of assessments.
Trapped-ion motion in ion cyclotron resonance spectroscopy

Abstract Equations are derived for ion motion in an ion cyclotron resonance (ICR) spectrometer in the absence of collisions and space charge. Both two- and three-dimensional quadrupolar electric field approximations are used. The three-dimensional approximation corresponds closely to fields which are present in the trapped-ion analyzer cell used in the pulsed ICR technique. A drift velocity is obtained for the two-dimensional case and compared to that found in the conventional ICR cell. Exact expressions for the potential and electric fields in the three-dimensional case are given, and values for these quantities at grid points within the cell are calculated. An analytical fit to the potential inside the cell is obtained, and from it equations of motion are derived for a trapped ion in the ICR cell. Various aspects of this three-dimensional ion motion and the qualitative effect of collisions upon ion loss from the cell are discussed. Several experimental considerations which arise from the analysis of ion motion are also presented.