cssi/SciSciGPT-SciSciNet huggingface dataset:
A critical current-margin design criterion for high performance magnet stability

Abstract A ‘critical-current-margin. (CCM) design criterion for superconducting magnet stability is presented. It is applicable to high-performance magnets that operate at high current densities; these magnets have cooled conductor surfaces, but their calculated heat fluxes are well beyond recovery values. For stability of a magnet based on this CCM design criterion, disturbances must be limited in size but need not be eliminated nor localized. The CCM criterion is compared with the MPZ/Cold-End Theory. It is shown that this criterion offers a much higher confidence level of stability than the MPZ/Cold-End Theory. Furthermore, and unique to this theory, stability is independent of current density in the stabilizer. The CCM criterion is based on two magnet winding elements: heat transfer and composite conductor. In this criterion heat transfer must always remain in the nucleate boiling region throughout the operation of a magnet. The design emphasis is on more superconductor and less stabilizer. It is also demonstrated that the CCM theory works particularly well with conductors such as cabled conductors that have high ratios of cooled perimeter to cross-section. Experimental results are presented supporting this CCM design criterion.
Induction of differentiation of human olfactory neuroblastoma cells into odorant-responsive cells

Olfactory neuroblastoma is a rare malignancy of the olfactory mucosa that may be derived from the olfactory epithelium. To characterize this tumor, we cultured olfactory neuroblastoma cells in the presence or absence of growth factors (transforming growth factor alpha and basic fibroblast growth factor) known to affect olfactory tissue and assessed their responsiveness to known odorants by measuring changes in intracellular calcium. Untreated cells did not respond to odorants. Basic fibroblast growth factor treatment had cytotoxic effects, and treated cells did not respond to odorants. Transforming growth factor alpha treatment resulted in the induction of odor responsiveness in these cells. Cells responded to odorants at 100 nM to 100 microM concentrations and responded with both increases and decreases in intracellular calcium. Increases in intracellular calcium were mediated by a calcium influx and were reversibly blocked by compounds known to inhibit second messenger pathways in olfactory receptor neurons. The calcium responses of the olfactory neuroblastoma cells were thus specific to the odorants and similar to those found in olfactory receptor neurons. The results support the notion that olfactory neuroblastoma cells may be of olfactory origin and thus they can be used as a model cell line to study human olfaction.
Research Methods for Studying Evolutionary and Ecological Processes in Organizational Communication

In a previous MCQ article, Monge et al. overviewed the fundamental concepts and processes of evolutionary theory and their applications to key issues in organizational communication. This article extends that work by providing an overview of research tools for studying organizational ecology and evolution, including (a) the variation-selection-retention sequence, (b) the likelihood of events occurring over a period of time (event history analysis), (c) transition sequence of populations from one state to another (sequence analysis), (d) relationships among nodes in networks over time (network analysis), (e) simulation of complex relationships and interactions (computational modeling), (f) changes in populations’ fitness for survival (NKC models), and (g) competitive interdependence among populations over time (predator—prey models). We conclude with a brief review of graphical and qualitative methods.
Chronology of labyrinthitis ossificans induced by Streptococcus pneumoniae meningitis.

Objective: Labyrinthitis ossificans consists of novel osteogenesis that fills the normally patent cochlear and vestibular lumen as an end-stage sequelae to various pathologies. This study was designed to establish the sequence of events and chronology of the osteoneogenesis and calcification. Study Design: A prospective randomized double-blind study. Methods: By using serial application of different colored fluorochromes, which deposit in newly forming bone, the timing of bone deposition and bone remodeling can be established. Labyrinthitis ossificans was induced in she groups (n = 5) of gerbils by an intrathecal injection of live Streptococcus pneumoniae. Group 1 received no fluorochrome labels, group 2 received one label, group 3 received three labels, and groups 4, 5, and 6 received four labels. The temporal bones were harvested after 2 weeks (group 1), 1 month (group 2), 3 months (group 3), 4 months (group 4), 6 months (group 5), and 12 months (group 6). Results: Sixteen of the 25 animals that received labels developed ossification, demonstrated with fluorescent microscopy. In the animals that developed labyrinthitis ossificans, newly formed disorganized bone began calcifying as early as 3 weeks (label 1) after S pneumoniae injection. Osteoneogenesis continued as evidenced by the presence of the other labels when first applied at 6 weeks (label 2), and 10 weeks (label 3). Ossification, calcification, and remodeling proceeded through a 12-month course, wherein a reduction of labels was present at 6 months and total disappearance by 12 months. Conclusions: The use of fluorescent stains in this animal model provides a means to establish a timeline of the ossification seen in labyrinthitis ossificans. Key Words: Ossified cochlea, labyrinthitis, deafness, cochlear implant, meningitis.
Complete Rupture of Both Heads of the Biceps Brachii Muscle Belly by Blunt Trauma

A young adult male pedestrian was struck by a car and sustained a closed complete rupture of both heads of the biceps brachii muscle belly, among other injuries. Rupture of the biceps brachii muscle belly is a rare injury, and complete muscle belly rupture of both long and short heads from direct blunt force trauma has not been reported outside of military parachutists. We describe the findings on magnetic resonance imaging (MRI) of this injury.
Structure of the Mtb CarD/RNAP β-lobes complex reveals the molecular basis of interaction and presents a distinct DNA-binding domain for Mtb CarD.

Summary CarD from Mycobacterium tuberculosis ( Mtb ) is an essential protein shown to be involved in stringent response through downregulation of rRNA and ribosomal protein genes. CarD interacts with the β-subunit of RNAP and this interaction is vital for Mtb 's survival during the persistent infection state. We have determined the crystal structure of CarD in complex with the RNAP β-subunit β1 and β2 domains at 2.1 A resolution. The structure reveals the molecular basis of CarD/RNAP interaction, providing a basis to further our understanding of RNAP regulation by CarD. The structural fold of the CarD N-terminal domain is conserved in RNAP interacting proteins such as TRCF-RID and CdnL, and displays similar interactions to the predicted homology model based on the TRCF/RNAP β1 structure. Interestingly, the structure of the C-terminal domain, which is required for complete CarD function in vivo, represents a distinct DNA-binding fold.
Mass balance and thermodynamic description of solid state fermentation of lignocellulosics by Pleurotus ostreatus for animal feed production

This study was focused primarily on the degradation of lignin in water hyacinth and barley straw for animal-feed production. The experiment was performed in a 1.5-L Applikon fermenter for 30 days, varying the air flow rate from 0.022 VVM/0.047 VMM to 0.048 VVM/0.102 VMM. A novel approach was introduced for prediction of a kinetic model by using instantaneous respiratory quotient (RQ) measurements and steady state elemental balances. Growth kinetics were determined for the fungus in a 30-day fermentation with a mixture of barley straw and water hyacinth as the substrate. The instantaneous heat-interaction profile was predicted from steady state balances. Fermentation data were checked for consistency using the entropy balance inequality, and thermodynamic efficiency was calculated to show that degradation of lignocellulosics byPleurotus ostreatus followed more than one metabolic pathway during the course of the fermentation. Growth ofP. ostreatus on lignocellulosics, such as water hyacinth and barley straw, was di-auxic or possibly tri-auxic during the 30 days of fermentation.
Phosphorylation of human CTP synthetase 1 by protein kinase A : Identification of Thr455 as a major site of phosphorylation

Phosphorylation of human CTP synthetase 1 by mammalian protein kinase C was examined. Using purified Escherichia coli-expressed CTP synthetase 1 as a substrate, protein kinase C activity was time- and dose-dependent and dependent on the concentrations of ATP and CTP synthetase 1. The protein kinase C phosphorylation of the recombinant enzyme was accompanied by a 95-fold increase in CTP synthetase 1 activity. Phosphopeptide mapping and phosphoamino acid analyses showed that CTP synthetase 1 was phosphorylated on multiple serine and threonine residues. The induction of PKC1(R398A)-encoded protein kinase C resulted in a 50% increase for human CTP synthetase 1 phosphorylation in the Saccharomyces cerevisiae ura7Delta ura8Delta mutant lacking yeast CTP synthetase activity. Synthetic peptides that contain the protein kinase C motif for Ser(462) and Thr(455) were substrates for mammalian protein kinase C, and S462A and T455A mutations resulted in decreases in the extent of CTP synthetase 1 phosphorylation that occurred in vivo. Phosphopeptide mapping analysis of S. cerevisiae-expressed CTP synthetase 1 mutant enzymes phosphorylated with mammalian protein kinase C confirmed that Ser(462) and Thr(455) were phosphorylation sites. The S. cerevisiae-expressed and purified S462A mutant enzyme exhibited a 2-fold reduction in CTP synthetase 1 activity, whereas the purified T455A mutant enzyme exhibited a 2-fold elevation in CTP synthetase 1 activity (Choi, M.-G., and Carman, G.M. (2006) J. Biol. Chem. 282, 5367-5377). These data indicated that protein kinase C phosphorylation at Ser(462) stimulates human CTP synthetase 1 activity, whereas phosphorylation at Thr(455) inhibits activity.
Energy- and Entropy-Based Stabilization for Lossless Dynamical Systems via Hybrid Controllers

A novel class of dynamic, energy-based hybrid controllers is proposed as a means for achieving enhanced energy dissipation in lossless dynamical systems. These dynamic controllers combine a logical switching architecture with continuous dynamics to guarantee that the system plant energy is strictly decreasing across switchings. The general framework leads to closed-loop systems described by impulsive differential equations. In addition, we construct hybrid dynamic controllers that guarantee that the closed-loop system is consistent with basic thermodynamic principles. In particular, the existence of an entropy function for the closed-loop system is established that satisfies a hybrid Clausius-type inequality. Special cases of energy-based and entropy-based hybrid controllers involving state-dependent switching are described.
Papillotomy Performance Scoring Scale – a pilot validation study focused on the cut axis

Summary Background No published Papillotomy Performance Scoring Scale exists. Aims To develop such a scale and to apply it to stratify the quality of performance of recorded papillotomies. Method Expert biliary endoscopists were polled regarding their opinion of a ‘perfect’ biliary papillotomy and experience with complications in relation to the cut axis. Based on these responses a scoring scale encompassing two components – wire alignment and cut orientation, was proposed. This scoring scale was presented to experienced and trainee endoscopists, who scored recording of five biliary papillotomies. The mean final combined score was used for stratification. Results The experts’ opinion of a ‘perfect’ biliary papillotomy is one cut along the axis of the distal bile duct and papilla. Their reported experience with complications occurring outside of the perfect axis validated their consensus. Application of the scoring scale stratified recorded papillotomies based on the mean final combined scores. Conclusions These pilot data support the hypothesis that a scoring scale focused on the cut axis can be constructed based on expert opinion, experience and consensus. The possibility of stratification of mean final combined scores that are significantly different validates application of the scoring scale for assessment of papillotomy performance.
A Delphi Study to Identify Personal Finance Core Concepts and Competencies of First‐Generation College Students

The purpose of this study was to gain consensus among researchers and college educators using the Delphi method about the personal finance knowledge, skills, and actions/behaviors that are important for all first-generation college students. A group of five experts who had knowledge of college students’ financial literacy needs participated as panelists. Three rounds of questionnaires elicited responses from the panelists to identify personal finance core concepts and competencies that are most crucial for first-generation college students. All 14 personal finance concepts and 234 competencies gained consensus. The mean rankings by importance of each personal finance concept and competency were identified.
A Temperature Scale for Tungsten

Temperature variation of the resistance of tungsten from 273\ifmmode^\circ\else\textdegree\fi{}K to 3655\ifmmode^\circ\else\textdegree\fi{}K.---In the range from 273\ifmmode^\circ\else\textdegree\fi{}K to 1500\ifmmode^\circ\else\textdegree\fi{}K measurements were made of the resistance of coils of pure, well-aged, tungsten filaments (diam. 2.61 mils) placed in the center of a constant temperature compartment of an alundum resistance furnace through which a stream of pure dry hydrogen was continuously passed. Temperatures were measured by a carefully standardized chromelalumel thermocouple. In the range 1200\ifmmode^\circ\else\textdegree\fi{}K to 3655\ifmmode^\circ\else\textdegree\fi{}K tungsten filaments (V shape, length 40-50 cm, diam. 2.61, 5.00 and 9.85 mils) were mounted in lamp bulbs and their resistances measured. Temperatures were determined by pyrometering against a standard lamp. The specific resistance of tungsten was found to vary from 5.00\ifmmode\times\else\texttimes\fi{}${10}^{\ensuremath{-}6}$ ohm cm at 273\ifmmode^\circ\else\textdegree\fi{}K to 117.1\ifmmode\times\else\texttimes\fi{}${10}^{\ensuremath{-}6}$ at 3655\ifmmode^\circ\else\textdegree\fi{}K.Temperature variation of the rate of radiation from tungsten filaments.---Lamps of the above type were also used to determine the variation with temperature of the energy radiated per ${\mathrm{cm}}^{2}$ of the tungsten filaments. Temperatures from 300\ifmmode^\circ\else\textdegree\fi{}K to 1500\ifmmode^\circ\else\textdegree\fi{}K were measured by the resistance method, from 1500\ifmmode^\circ\else\textdegree\fi{}K to 3655\ifmmode^\circ\else\textdegree\fi{}K by the optical pyrometer. The rate of radiation varied from.000016 watts/${\mathrm{cm}}^{2}$ at 300\ifmmode^\circ\else\textdegree\fi{}K to 399.4 at 3655\ifmmode^\circ\else\textdegree\fi{}K.
Maximizing Seed Production in Eastern Gamagrass

Use of eastern gamagrass (Tripsacum dactyloides L.) for grazing or cut forage has been partially limited because of indeterminate inflorescence development combined with low seed yields and high seed costs caused by high seed shattering. This study was conducted to observe the influence of N rate and defoliation on inflorescence appearance, seed loss, and viability of harvested seed in two cultivars of eastern gamagrass at Boone, IA, in 2000 and 2001. Treatments included application of N at 0, 56, 112, 224 kg ha - 1 and spring, fall, and no defoliation. Cultivar had the greatest influence on seed yield. 'Pete' produced greater total numbers of terminal and lateral inflorescences and cupules than 'Iuka' in both years. Reductions in seed production occurred with spring defoliation in Iuka for the first year of the study and Pete during both years. In 2000, seed on lateral inflorescences was decreased 20% during the peak seed load. In 2001, seed yield for spring-defoliated plants of Pete was less than that of fall-defoliated plants, but not significantly different from nondefoliated plants. Addition of 56 kg ha - 1 N increased seed load in the second year of the study. Optimal harvest time occurred approximately 2 wk after terminal cupules began shattering. Seed harvested 1 wk earlier than this had 5 to 15 percentage points more immature seed. Seed yield was 13 to 20% less if harvests were taken 1 wk later than the optimal date.
Transcatheter occlusion of patent ductus arteriosus with Gianturco coils.

BACKGROUNDTranscatheter occlusion with Gianturco coils has been attempted in a small number of patients with tiny (< or = 1.5-mm diameter) patent ductus arteriosus, and preliminary results have been encouraging. The present study extends this method to larger ductus sizes and makes recommendations for proper coil size selection.METHODS AND RESULTSCoil occlusion was attempted in 24 consecutive patients with patent ductus arteriosus who did not require other cardiac surgery. Median patient age was 4.2 years (8 months to 30 years), and mean ductus diameter was 1.7 +/- 0.8 mm. Two instances of coil embolization occurred in the first 4 patients, with successful coil retrieval. Based on this experience, we proposed that the coil helical diameter should be twice or more the minimum ductus diameter, with coil length sufficient for three or more loops. With these recommendations, coils were successfully implanted in the subsequent 20 consecutive patients. Of the 22 patients with successful coil implantation, 15 (6...
Anisotropy of surface composition in a NiAu alloy

Abstract The anisotropy of the equilibrium surface composition in a Ni-0.1 at%Au alloy has been studied in a polycrystalline alloy. Surface compositions of 38 (randomly oriented) grains have been obtained in a scanning Auger microprobe after equilibration of the alloy at four temperatures in the range 810 to 900°C, and corresponding surface orientations have been determined by selected area channelling patterns in a scanning electron microscope. Experimental heats and entropies of segregation obtained from different grains have been found to vary by a factor of three, indicating a high degree of anisotropy. The experimental results have been compared with the results of calculations based on a nearest neighbor bond model which incorporates solute strain energy effects. The predictions of this model do not properly account for either the observed degree of anisotropy or the experimentally determined pattern of surface segregation anisotropy.
The influence of a homologous protein impurity on lysozyme crystal growth

Abstract The effect of a structurally similar protein impurity, turkey (Meleagris gallopavo) egg-white lysozyme (TEWL) on crystallization of the host protein, hen-egg-white lysozyme (HEWL) from chicken (Gallus gallus) was studied under varying impurity and host solution concentrations. A change in morphology is observed when crystals of HEWL are grown in the presence of TEWL. As the relative amount of TEWL increases, HEWL crystals become more elongated in the [0 0 1] direction. Elongation is more pronounced in samples with lower initial concentrations of HEWL than in samples with higher initial concentrations. This behavior is consistent with that of impurities in small molecule crystal growth and with predictions based on the Kubota–Mullin model. The observed effect on the growth process can be attributed to the apparent inhibition in the [1 1 0] crystal growth direction of HEWL by TEWL since slowly growing faces become dominant faces in crystal growth. Incorporation of TEWL into HEWL crystals grown in a sitting drop batch method was measured using cation exchange chromatography. The results indicate that impurity incorporation is associated with increasing supersaturation. This conclusion is consistent with a kinetically controlled process of impurity incorporation. The observed impurity effects are most probably associated with the interchange of glutamine in position 41 of HEWL by histidine in TEWL.
Overt vs. Covert Movements

In a number of cases (involving, e.g., negation, only, reverse scope of some and every, ACD) where covert (LF) phrasal movement has been postulated, it is possible and advantageous to dispense with covert movement (including feature raising) and replace it with a combination of overt movements of phonetically realized phrases. The strongest interpretation of this conclusion is that the cases explicitly considered are typical. UG leaves no choice: Scope must be expressed hierarchically, there are no covert LF phrasal movements permitted by UG, and neither can the effect of covert phrasal movement be achieved by feature raising. Scope reflects the interaction of merger and overt movement.
Survival in esophageal high-grade dysplasia/adenocarcinoma post endoscopic resection.

Abstract Background Endoscopic resection followed by ablative therapy is frequently used to treat esophageal high-grade dysplasia or early esophageal adenocarcinoma. Aims To study outcomes in patients with high-grade dysplasia compared to those with esophageal adenocarcinoma after endoscopic resection. Methods Retrospective, observational, descriptive, single-centre study from a prospective database. We extracted data from 116 endoscopic resections. Survival was plotted using Kaplan–Meier curves multivariable Cox-proportional hazard assess for possible predictors of survival post-endoscopic resection was performed. Results 116 patients (64 esophageal adenocarcinoma, 52 high-grade dysplasia) underwent endoscopic resection from May 2003 to June 2010. Mean age was 71 ± 11 years for high-grade dysplasia and 72 ± 10 years for esophageal adenocarcinoma. Median follow-up was 17 months. Eighty-five patients had negative margins on endoscopic resection. Five-year survivals for high-grade dysplasia and esophageal adenocarcinoma were 86% (range 68–100%) and 78% (59–96%), respectively. Survival was not significantly different between groups (p = 0.20). Overall mortality rate was 10.6% (9/85). At multivariable Cox regression increased Barrett's oesophagus length was associated with worse survival (HR 1.18 [1.06–1.33], p = 0.0039). Survival was not affected by the pathology before resection: HR 2.4 [95%CI, 0.70–8.4], p = 0.16. Conclusions Survival in patients with high-grade dysplasia of the oesophagus is similar to those with esophageal adenocarcinoma. Longer Barrett's oesophagus segments are associated with decreased survival.
In the Hyphen: Perceptions, Benefits, and Challenges of Social Workers’ Dual Identity as Clinician–Client:

This study is the first to directly inquire into the experience of clinical social workers who live “in the hyphen,” having received psychiatric diagnoses and/or been in therapy themselves. Rather than inhabiting these roles sequentially as previous studies suggest, many inhabit them simultaneously. Social workers who took part in this qualitative thematic analysis describe the benefits of living in the hyphen, such as greater understanding of client resistance and opportunity to serve as a model of realistic hope, as well as its challenges, including countertransference, retraumatization, and fear of being “outed.” Overall, the experience of “sitting in the other chair” was more important to participants than having a skillful therapist as a role model or sharing a specific diagnostic history with a client, which they cautioned did not offer a shortcut to authentic understanding or formation of a therapeutic alliance.
Graphical Techniques for Aircraft Dynamic Model Development

The complexity and expense of modern aircraft development programs drives the need for mathematical models of aircraft dynamic behavior at all stages in a design cycle. The limitations of graphical tools have meant that many system engineers have continued to rely on the historical practice of developing models using FORTRAN or C, a tedious and errorprone approach. Often, the reuse of models from stage to stage is limited or difficult, creating the possibility that differences in the models could exist and leading to incorrect results. Today’s well established, commercial off-the-shelf (COTS) products free designers from the need to create, manage, and understand models written in textual programming languages. These products provide a unified environment in which designers can model all system dynamic characteristics accurately.
E-beam-Cure Fabrication of Polymer Fiber/Matrix Composites for Multifunctional Radiation Shielding

Aliphatic polymers were identified as optimum radiation polymeric shielding materials for building multifunctional structural elements. Conceptual damage-tolerant configurations of polyolefins have been proposed but many issues on the manufacture remain. In the present paper, we will investigate fabrication technologies with e-beam curing for inclusion of high-strength aliphatic polymer fibers into a highly cross-linked polyolefin matrix. A second stage of development is the fabrication methods for applying face sheets to aliphatic polymer closed-cell foams.
Inhibition of Antiapoptotic BCL-XL, BCL-2, and MCL-1 Proteins by Small Molecule Mimetics

Informatics and computational design methods were used to create new molecules that could potentially bind antiapoptotic proteins, thus promoting death of cancer cells. Apoptosis is a cellular process that leads to the death of damaged cells. Its malfunction can cause cancer and poor response to conventional chemotherapy. After being activated by cellular stress signals, proapoptotic proteins bind antiapoptotic proteins, thus allowing apoptosis to go forward. An excess of antiapoptotic proteins can prevent apoptosis. Designed molecules that mimic the roles of proapoptotic proteins can promote the death of cancer cells. The goal of our study was to create new putative mimetics that could simultaneously bind several antiapoptotic proteins. Five new small molecules were designed that formed stable complexes with BCL-2, BCL-XL, and MCL-1 antiapoptotic proteins. These results are novel because, to our knowledge, there are not many, if any, small molecules known to bind all three proteins. Drug-likeness studies performed on the designed molecules, as well as previous experimental and preclinical studies on similar agents, strongly suggest that the designed molecules may indeed be promising drug candidates. All five molecules showed “drug-like” properties and had overall drug-likeness scores between 81% and 96%. A single drug based on these mimetics should cost less and cause fewer side effects than a combination of drugs each aimed at a single protein. Computer-based molecular design promises to accelerate drug research by predicting potential effectiveness of designed molecules prior to laborious experiments and costly preclinical trials.
A Large Time-Bandwidth Product Pulse-Compression Technique

A pulse-compression radar system which utilizes a linear FM waveform has a theoretical upper limit to the magnitude of its compression ratio or time-bandwidth product. This limit is a function of the observed target's relative radial velocity, and the effect on the return signal is characterized by both a pulse stretching and amplitude reduction if the limit is exceeded. The use of a logarithmic phase-modulation signal waveform and a corresponding ``matched'' receiver possesses the desirable characteristics of the linear FM and in addition has no upper limit to the magnitude of the compression ratio. A single receive pulse-compression filter is matched for all target velocities. A linear FM signal can be thought of as a very good approximation to a logarithmic phase-modulation signal for compression ratios less than the maximum limit. A general method of implementing a variety of systems employing pulse-compression ratios up to 105 and utilizing logarithmic phase modulation is presented.
Nurses at the Edge of Chaos The Application of "New Science" Concepts to Organizational Systems

In recent years, "new science" concepts stemming from self-organizing systems theory, chaos theory, and complexity theory have captured the attention of both social scientific researchers and pract...
Silicon microfabricated column with microfabricated differential mobility spectrometer for GC analysis of volatile organic compounds.

A 3.0-m-long, 150-μm-wide, 240-μm-deep channel etched in a 3.2-cm-square silicon chip, covered with a Pyrex wafer, and coated with a dimethyl polysiloxane stationary phase is used for the GC separation of volatile organic compounds. The column, which generates ∼5500 theoretical plates, is temperature-programmed in a conventional convection oven. The column is connected through a heated transfer line to a microfabricated differential mobility spectrometer. The spectrometer incorporates a 63Ni source for atmospheric-pressure chemical ionization of the analytes. Nitrogen or air transport gas (flow 300 cm3/min) drives the analyte ions through the cell. The spectrometer operates with an asymmetric radio frequency (RF) electric field between a pair of electrodes in the detector cell. During each radio frequency cycle, the ion mobility alternates between a high-field and a low-field value (differential mobility). Ions oscillate between the electrodes, and only ions with an appropriate differential mobility reach...
Guanidine-dependent mutants of poliovirus: identification of three classes with different growth requirements

Four mutants resistant to high (2.0 mM) guanidine were derived from a mutant resistant to intermediate (0.53 mM) levels of this drug. One of these mutants was found to be resistant to high guanidine and was shown to contain a mutation within 2C seen previously in this class of mutants, while lacking the mutation seen in the intermediate parent. The other three mutants were dependent on guanidine for growth and contained the mutation in 2C seen in the parental virus as well as a mutation seen previously in another dependent mutant. Comparison of the newly isolated dependent mutants to two previously described dependent mutants revealed that three classes of dependent mutants which vary in their requirements for optimal growth can be observed. We present a model for the interaction of guanidine with 2C that explains the occurrence of the three classes of dependent mutants.
Enzymatic pathways in the pathogenesis of hereditary angioedema: The role of C1 inhibitor therapy

A functional abnormality of C1 inhibitor (C1INH) is present in types I and II hereditary angioedema (HAE), and normal C1INH may be rendered ineffective in the newly described type III HAE. C1INH inhibits factor XIIa, factor XII fragment (XIIf), kallikrein, and plasmin. Thus, in its absence, there is marked activation of the bradykinin-forming cascade resulting in severe angioedema. Factor XII may autoactivate on binding to endothelial cell surface gC1qR (receptor for the globular heads of C1q) thus initiating the cascade. Alternatively, stimuli that activate endothelial cells may liberate (or express at the cell surface) heat shock protein 90 or the enzyme prolylcarboxypeptidase, either of which can interact with the prekallikrein-high-molecular-weight kininogen complex to convert prekallikrein to kallikrein stoichiometrically. The kallikrein produced can cleave high-molecular-weight kininogen to produce bradykinin and also recruit factor XII by enzymatically activating it. Patients with type I or II HAE have mutant C1INH so that control of C1 activation is lost. Autoactivation of C1r in the absence of C1INH leads to C1s activation followed by C4 cleavage and depletion. An attack of swelling is accompanied by conversion of factor XIIa to factor XIIf and further enzymatic activation of C1r so that C4 levels drop further and C2 is depleted. New therapies for HAE focus on the bradykinin-forming cascade and include a kallikrein inhibitor and a bradykinin B-2 receptor antagonist in addition to administration of purified C1INH.
The evaluation of potato seedling varieties for field immunity from potato virus A

Procedures for the efficient and effective evaluation of potato seedling varieties for field immunity from potato virus A in the greenhouse were developed. Plants of seedling varieties selected from parents possessing field immunity are inarch-grafted with virus-A-infected plants of potato seedling 41956 to eliminate from further tests seedling varieties that show top necrosis and are, thus, field-immune from the virus. Subinoculations to plants ofSolanum demissum P. I. 175404 (local-lesion host) from mottled or symptomless plants about 35 days after grafting will detect, in 4 to 6 days, all seedling varieties susceptible to virus A. These susceptible seedling varieties are replanted, and when the plants are 1 to 2 inches tall they are infested with 25 to 50 virus-A-infective aphids for a 24-hour-period. After an incubation period of 30 to 35 days, diagnosis of infection is made by subinoculation from each plant to the indicator host. Seedling varieties not infected by aphid inoculation are considered field-immune from virus A.
Mater encodes a maternal protein in mice with a leucine-rich repeat domain homologous to porcine ribonuclease inhibitor.

MATER (Maternal Antigen That Embryos Require) is an ooplasm-specific protein first identified as an antigen (OP1) associated with ovarian autoimmunity in mice. Its primary structure has been deduced from full-length cDNA that encodes a 125-kDa protein required for progression of the mouse embryo beyond two cells. Expression of the gene encoding MATER is restricted to the oocyte, which makes it one of a growing, but still limited, number of maternal-effect genes in mammals. To further investigate the function of MATER during oogenesis and early development, we have characterized the gene and resultant protein. Mater is a single-copy gene in the genome of 129/Sv mice and is located at the proximal end of Chromosome (Chr) 7. The gene, spanning approximately 32 kbp, contains 15 exons ranging in size from 48 to 1576 bp, which together encode the 1111 amino acid MATER protein. The first five exons encode 26–27 amino acid hydrophilic repeats, and exons 8–14 encode 14 leucine-rich repeats. The three-dimensional structure of the latter domain can be closely modeled on the previously determined X-ray crystallographic coordinates of porcine ribonuclease inhibitor. These characterizations of the gene and protein provide the basis for genetic investigations of MATER function in early mammalian development.
Predictive Value of HLA Antibody Characteristics in Progression of Subclinical Antibody Mediated Rejection in Heart Transplant Recipients

Purpose Donor specific antibody (DSA) is a risk factor for antibody-mediated rejection (AMR). Concomitant detection of C4d & C3d in heart biopsies correlates with DSA and allograft dysfunction. Detection of C4d only in surveillance biopsies may not be associated with allograft dysfunction. However, conversion from C4d only to C4d + C3d is noted in ~20% of cases (C4d converters). We studied DSA patterns in clinical (C4d+C3d+ & C4d converters) & subclinical (C4d+) AMR. Methods and Materials Of 1589 transplants, 610 were screened for AMR (last 6 yr). We studied DSA patterns in C4d+ asymptomatic patients, C4d+C3d+ biopsies symptomatic patients & patients who started as C4d+ & converted to C4d+C3d+. We also compared cPRA & crossmatches. Results Significant differences in DSA incidence, mean cPRA, & DSA mean MFI were noted across all groups with C4d+ patients having the lowest values ( table 1 ). DSA mean MFI was significantly higher in patients with clinical AMR ( table 1 ). C4d converters had significantly higher mean cPRA & DSA, driven by higher DQ DSA but not class I DSA compared to patients who remained C4d+ ( Table 2 ). Having any DSA, DQ DSA or cPRA≥50% at time of biopsy was associated with C4d conversion with high -ve predictive value (NPV) but low +ve predictive value (PPV). Conclusions Our data suggest that HLA antibody characteristics may be relevant in determining which subclinical C4d+ may not progress to clinical AMR & warrants investigation in larger cohorts. Table 1 Any DSA DSA Cl I DSA Cl II DSA Cl I +II mean ± SE cPRA mean ± SE MFI C4d+: n=34 19, 56% 9, 26% 12, 35% 2, 6% 44.8 ± 5.1 7398.5 ± 1525.1 C4d+C3d+: n=30 28, 93% 20, 67% 26, 87% 18, 60% 87.4 ± 5.4 12633.0 ± 1222.8 C4d conv: n=11 11, 100% 4, 36% 10, 91% 3, 27% 81.1 ± 8.9 8378.2 ± 1950.9 p .0003 .005 .022 Table 2 Any DSA DSA Cl I DSA Cl II DR DSA DQ DSA cPRA≥50 C4d+: n=34 19, 56% 9, 26% 12, 35% 3, 9% 11, 32% 16, 47% C4d conv: n=11 11, 100% 4, 36% 10, 91% 6, 55% 9, 82% 10, 91% p .008 .70 .002 .003 .004 .014 PPV .38 .30 .46 .67 .45 .39 NPV 1 .78 .96 .86 .92 .95
Copying patient letters – making it work

Purpose – That patients should be able to receive a copy of any letter written about them is part of the British Government's policy to increase patients' involvement in their care and treatment. All National Health Service (NHS) organisations are expected to implement this by April 2005. This paper aims to describe how one acute Trust has used basic change management principles to implement the initiative.Design/methodology/approach – Examines the approach of the Salisbury Health Care NHS Trust, where initially a survey of all consultants, senior nurses and allied health professionals was carried out.Findings – Initial concerns that patients would not understand the letter were generally unfounded with 98.9 per cent of patients saying that they understood their letter. Of patients, 96.9 per cent said that they found receiving a copy letter useful.Originality/value – The research demonstrated a high percentage of patients wanting a copy letter, which has huge resource implications in terms of secretarial ...
Evolution of Emotional Symptoms Over Time Among Daughters of Patients With Breast Cancer

Objective This study longitudinally profiled anxiety and depressive symptoms of daughters of patients with breast cancer and examined the mother׳s survival status, the daughter׳s age at the time of mother׳s diagnosis, and the style of family communication about breast cancer as moderators of change in symptomatology across participants׳ first 3 appointments at the University of California, Los Angeles Revlon Breast Center High Risk Clinic. Methods We evaluated the effects of hypothesized predictors on change in anxiety and depressive symptoms, 3 (symptomatology at first, second, and third clinic visits) × 2 (mother survived or died) × 2 ( Results There was a main effect for time of diagnosis on state anxiety, demonstrating a significant reduction in anxiety across clinic visits overall ( p p = 0.001). For daughters whose mothers survived, anxiety was decreased for those with closed family communication styles ( p = 0.001). The time of diagnosis × mother׳s survival × age at diagnosis interaction was also significant for depressive symptoms ( p = 0.001). Among daughters whose mothers died, those who were younger showed decreases in symptoms ( p = 0.004). Conclusion These daughters appeared to benefit from the high-risk program as demonstrated by decreased symptomatology, particularly daughters whose mothers died who were younger at the time of diagnosis.
Abnormal gastric emptying response to pentagastrin in duodenal ulcer disease.

The effect of pentagastrin on gastric emptying in duodenal ulcer disease (DU) is unknown. The evaluation of this effect is complicated by the simultaneous action of the hormone on gastric secretion. We compared gastric emptying and net gastric output in 17 patients with active DU to that of 11 healthy controls. A dye-dilution technique was used to determine net acid output, net fluid output, fractional emptying rate, and acid emptying rate during a basal period and after pentagastrin (6 μg/kg/hr, intravenously). Net basal acid output observed in controls (54±10 μEq/min; mean±se) was used as the primary criterion for separating DU patients into 12 normosecretor (30±10 μEq/min) and 5 hypersecretor patient groups (163±40 μEq/min). The pentagastrin-stimulated net acid output was significantly greater in hypersecretor patients than in controls (P<0.01) but was normal in normosecretor patients. Basal fractional emptying and acid emptying rates were significantly greater in hypersecretors than in controls (P<0.05) but were normal in normosecretors. In contrast, both normo- and hypersecretor patients had significantly greater fractional emptying (P<0.01) and acid emptying rates than controls (P<0.05) during pentagastrin infusion. Thus, a greater load of acid transiently enters the duodenum in duodenal ulcer disease following pentagastrin stimulation, even in the absence of gastric hyperscretion.
Race and Ethnic Group Differences in Comorbid Major Depressive Disorder, Generalized Anxiety Disorder, and Chronic Medical Conditions

This study tested whether race and ethnic group differences exist for lifetime major depressive disorder and/or general anxiety disorder with one or more chronic medical conditions. Data from the National Survey of American Life, which included 3570 African American, 1438 Caribbean Black, and 891 non-Hispanic White adults were analyzed. Outcomes included at least one and multiple chronic medical conditions, from a list of 14 medical conditions (e.g., arthritis, cancer, diabetes, kidney disease, stroke, heart disease, etc.). Logistic regressions were fitted to data to determine how the association between major depressive disorder, general anxiety disorder, and one or more chronic medical conditions vary across race and ethnicity. Lifetime major depressive disorder (but not lifetime general anxiety disorder) was associated with at least one chronic medical condition among African Americans and Caribbean Blacks, but not non-Hispanic Whites. Lifetime major depressive disorder was similarly associated with multiple chronic medical conditions among African Americans, Caribbean Blacks, and non-Hispanic Whites. For Caribbean Blacks, stronger associations were found between major depressive disorder and general anxiety disorder with one or more chronic medical conditions compared to African Americans and non-Hispanic Whites. Findings suggest that race and ethnicity may shape the links between comorbid psychiatric disorders and chronic medical conditions. Mental health screening of individuals with chronic medical conditions in primary health-care settings may benefit from tailoring based on race and ethnicity. More research is needed to understand why associations between physical and mental health vary among race and ethnic groups.
Sclerosing variants of follicular center cell lymphomas presenting in the retroperitoneum

A study of 22 patients with sclerosing variants of follicular center cell lymphoma (FCCL) presenting as a retroperitoneal mass is reported. These FCCL variants comprise 74% of retroperitoneal non-Hodgkin's lymphoma presentations. A partial intranodal follicular growth pattern was present in each case, and marked sclerosis of a distinctive pattern was associated with extensive perinodal lymphomatous infiltration. Small cleaved cells (SCC) predominated in five cases, large cleaved cells (LCC) in 14, and large noncleaved cells (LNCC) in three. Eighty percent of patients with SCC predominance were Stage I-II, compared to 50% of those with LCC predominance; all three LNCC cases were Stage IV. High stage was attained primarily by renal invasion or infiltration out the mesenteric root into gut or omentum; only three patients had biopsy proven extraabdominal disease. Combined modality therapy achieved an 88% complete or partial remission rate in patients with SCC and LCC predominance; all three LNCC patients died.
Upstream flanking sequences and transcription of SINEs.

SINEs, short interspersed repeated DNA elements, undergo amplification through retroposition and subsequent integration into a new location in the genome. Each new SINE insertion will be located in a new chromosomal environment, with different flanking sequences. Modulation of transcription by different flanking sequences may play an important role in determining which SINE elements are preferentially active in a genome. We evaluated the ability of upstream flanking sequences to regulate the transcription of three different SINEs (Alu, B2 and ID) by constructing chimeric constructs with known 5′ flanking sequences of RNA polymerase III-transcribed genes. Upstream sequences from the 7SL RNA gene, U6 RNA gene, vault RNA gene, and BC1 gene increase transcription of Alu, B2 and BC1 in transient transfections of NIH3T3, HeLa, Neuro2a and C6 glioma cell lines. The 7SL sequence proved most efficient in increasing SINE transcription. The 7SL upstream fused to the BC1 RNA gene (an ID element) was used to create a transgenic mouse line. In contrast to the tissue-specific endogenous BC1 transcription, BC1 transgene transcripts were detected in all tissues tested. However, expression was much higher in those tissues that express the endogenous gene, demonstrating both transcriptional and post-transcriptional regulation. The BC1 RNA was detected in a similar ribonucleoprotein complex in the different tissues.
Multipressure Polytropes as Models for the Structure and Stability of Molecular Clouds. I. Theory

We present a theoretical formalism for determining the structure of molecular clouds and the precollapse conditions in star-forming regions. The model consists of a pressure-bounded, self-gravitating sphere of an ideal gas that is supported by several distinct pressures. Since each pressure component is assumed to obey a polytropic law Pi(r) ∝ ργpi, we refer to these models as "multipressure polytropes." We treat the case without rotation. The time evolution of one of these polytropes depends additionally on the adiabatic index γi of each component, which is modified to account for the effects of any thermal coupling to the environment of the cloud. We derive structure equations as well as perturbation equations for performing a linear stability analysis. Special attention is given to representing properly the significant pressure components in molecular clouds: thermal motions, static magnetic fields, and turbulence. The fundamental approximation in our treatment is that the effects of turbulent motions in supporting a cloud against gravity can be approximated by a polytropic pressure component. In particular, we approximate the turbulent motions as a superposition of Alfven waves. We generalize the standard treatment of the stability of polytropes to allow for the flow of entropy in response to a perturbation, as expected for the entropy associated with wave pressure. In contrast to the pressure components within stars, the pressure components within interstellar clouds are "soft," with polytropic indices γpi ≤ 4/3 and (except for Alfven waves) adiabatic indices γi ≤ 4/3. This paper focuses on the characteristics of adiabatic polytropes with a single pressure component that are near the brink of gravitational instability as a function of γpi and γi for γpi ≤ 4/3. The properties of such polytropes are generally governed by the conditions at the surface. We obtain upper limits for the mass and size of polytropes in terms of the density and sound speed at the surface. The mean-to-surface density and pressure drops are limited to less than a factor 4 for γp ≤ 1, regardless of the value of γ. The central-to-surface density and pressure drops in isentropic clouds (γi = γpi) are also limited, but they can become quite large (as observed) in nonisentropic clouds, which have γi > γpi. We find that the motions associated with Alfven waves are somewhat less effective in supporting clouds than are the kinetic motions in an isothermal gas.