cssi/SciSciGPT-SciSciNet huggingface dataset:
Mechanistic picture for conformational transition of a membrane transporter at atomic resolution

During their transport cycle, ATP-binding cassette (ABC) transporters undergo large-scale conformational changes between inward- and outward-facing states. Using an approach based on designing system-specific reaction coordinates and using nonequilibrium work relations, we have performed extensive all-atom molecular dynamics simulations in the presence of explicit membrane/solvent to sample a large number of mechanistically distinct pathways for the conformational transition of MsbA, a bacterial ABC exporter whose structure has been solved in multiple functional states. The computational approach developed here is based on (i) extensive exploration of system-specific biasing protocols (e.g., using collective variables designed based on available low-resolution crystal structures) and (ii) using nonequilibrium work relations for comparing the relevance of the transition pathways. The most relevant transition pathway identified using this approach involves several distinct stages reflecting the complex nature of the structural changes associated with the function of the protein. The opening of the cytoplasmic gate during the outward- to inward-facing transition of apo MsbA is found to be disfavored when the periplasmic gate is open and facilitated by a twisting motion of the nucleotide-binding domains that involves a dramatic change in their relative orientation. These results highlight the cooperativity between the transmembrane and the nucleotide-binding domains in the conformational transition of ABC exporters. The approach introduced here provides a framework to study large-scale conformational changes of other membrane transporters whose computational investigation at an atomic resolution may not be currently feasible using conventional methods.
Computing trends in small liberal arts colleges

This paper summarizes the information gathered by the author during visits to 40 small liberal arts colleges in the east and Midwest during the winter of 1987. It focuses on the following questions: What is happening with computer science programs as colleges are coping with declining computer science enrollments? What trends are noticeable in staffing levels of computing faculty and of administrative and academic computing center support staff? How should colleges balance mainframe and micro computing and how many public access microcomputers are enough? Should students be required or strongly urged to buy a microcomputer? Should colleges provide faculty and administrators with microcomputers? What about networking? The paper provides tables and graphs to help small colleges answer these questions.
The Renin Angiotensin System in Newborn Dogs: Developmental Patterns and Response to Acute Saline Loading

Summary: Plasma renin (PRC) and aldosterone concentrations are known to be high during early postnatal life. Whether this is related to the low rates of renal blood flow or to sodium homeostasis remains unknown. Measurements of PRC, renal blood flow, and its intrarenal distribution were performed in 1- to 3-wk-old puppies subjected to maneuvers known to stimulate or inhibit renin release. In the awake state, PRC was observed to be higher in 2-wk-old puppies than in older or younger dogs, (P < 0.0001). Significant differences in PRC were also found between litters (P < 0.0001), but they did not account for the age-related changes. Anesthesia resulted in a 3- to 5-fold rise in PRC, whereas saline expansion suppressed PRC at all ages, the fall tending to become progressively greater with age (P < 0.09). There was no significant correlation between the age-related changes in PRC and those in renal blood flow or its intrarenal distribution. The results of these experiments demonstrate that in the newborn from a qualitative point of view, PRC changes appropriately in response to various stimuli. However, quantitative age-related differences exist in this regard, reflecting an initial immaturity of the feedback system.
A Robust Discrete State Approximation to the Optimal Nonlinear Filter for a Diffusion.

A robust computable approximation to the nonlinear filtering problem for a diffusion model is treated, where the system and data models are given by . The approximation (with approximation parameter h) is robust in the sense that it is locally Lipschitz continuous in the data y( °) (sup norm) uniformly in h and, as h→0, it converges to the optimal filter for the diffusion.
Optical Heterodyning for Reduction of Chromatic Dispersion Sensitivity in 60 GHz Mode-Locked Laser Systems

In this paper, a method is proposed to reduce the sensitivity to chromatic dispersion over a fiber optic link based on mode-locked lasers for Millimeter Waves (MMW) generation and transmission. The simulation presented here gives an estimation of the length margin of fiber available for radio-over-fiber networks with minimal sensitivity and maximum received MMW power. The simulation results are verified experimentally by means of a 60 GHz mode-locked laser system combined with an unbalanced Mach Zehnder interferometer for the compensation of the impact of dispersion effects on transmitted MMW power and fiber length range.
Unsuspected osteomyelitis in diabetic foot ulcers. Diagnosis and monitoring by leukocyte scanning with indium in 111 oxyquinoline

Objective. —The prevalence of osteomyelitis in diabetic foot ulcers is unknown. Early diagnosis of this infection is critical, as prompt antibiotic treatment decreases the rate of amputation. We therefore assessed the prevalence of osteomyelitis in 35 diabetic patients with 41 foot ulcers. We compared results of roentgenograms, leukocyte scans with indium In 111 oxyquinoline, and bone scans with the diagnostic criterion standards of bone histologic and culture findings. Leukocyte scans were repeated at 2- to 3-week intervals during antibiotic treatment. Design. —Cohort study. Setting. —Institutional and private, ambulatory and hospitalized patients. Patients. —Consecutive sample of 54 diabetic patients. Thirty-five patients with 41 foot ulcers were included. Results. — As determined by bone biopsy and culture, osteomyelitis was found to underlie 28 (68%) of 41 diabetic foot ulcers. Only nine (32%) of the 28 cases were diagnosed clinically by the referring physician. Underscoring the clinically silent nature of osteomyelitis in these ulcers, 19 (68%) of 28 occurred in outpatients, 19 (68%) of 28 occurred in ulcers not exposing bone, and 18 (64%) of 28 had no evidence of inflammation on physical examination. All patients with ulcers that exposed bone had osteomyelitis. Of the imaging tests, the leukocyte scan had the highest sensitivity, 89%. In patients with osteomyelitis, the leukocyte scan image intensity decreased by 16 to 34 days of antibiotic treatment and normalized by 36 to 54 days. Conclusion. —The majority of diabetic foot ulcers have an underlying osteomyelitis that is clinically unsuspected. Leukocyte scans are highly sensitive for diagnosing osteomyelitis in diabetic foot ulcers and may be useful for monitoring the efficacy of antibiotic treatment. We recommend that diabetic patients with foot ulcers that expose bone should be treated for osteomyelitis. Diabetic patients with foot ulcers that do not expose bone should undergo leukocyte scanning, which eliminates the risk of bone biopsy in diagnosing osteomyelitis and allows for the diagnosis and treatment of this well-known but often silent precursor of lower extremity amputation. ( JAMA . 1991;266:1246-1251)
The Revised Behavior and Symptom Identification Scale (BASIS-R): reliability and validity.

Background:To assess outcomes of health services, providers need brief, responsive, reliable, and valid measures that can be implemented in clinical settings with minimal cost and burden. The Behavior and Symptom Identification Scale (BASIS-32®) is a self-report measure developed in 1984 to assess m
Thermal conductivities of Li, Na, K, and Ag β -alumina below 300 K

The thermal conductivities of single-crystal Li, Na, K, and Ag $\ensuremath{\beta}$-alumina have been measured in the temperature range of $\ensuremath{\approx}0.1\ensuremath{-}300$ K. The thermal conductivity is very sensitive to the cation present and is indicative of a broad band of excitations ($\ensuremath{\lesssim}{10}^{\ensuremath{-}21}$J, $\ensuremath{\lesssim}{10}^{12}$ Hz) which scatter thermal phonons. The results are compared with a tunneling-states theory of disordered materials and with published data from specific-heat and light-scattering measurements.
Estimates of average major ion concentrations in bulk precipitation at two high-altitude sites near the continental divide in southwestern colorado

Abstract The composition of bulk precipitation from two high-altitude sites, established in 1971 near the Continental Divide in southwestern Colorado, has been monitored by season during the past decade. Calcium ions are the predominant cationic species; sulfate is the major anionic consitituent. Bulk precipitation major ion concentrations exhibit log-normal distributions. Representative mean and standard deviation values for the major inorganic ionic species present in bulk precipitation have been calculated for three years of consecutive seasons. Standard deviations for all species, except nitrate, are similar. For two years of data grouped into quarters, deviations from mean values fall well within the plus or minus two standard deviation limit. There does not seem to be a systematic deviation from the mean concentration values, with respect to either ionic component or season.
The practice of archaeology in southern Mesoamerica

Joyce, Rosemary A. Cerro Palenque: Power and Identity on the Maya Periphery. Austin: University of Texas Press, 1991. x + 188 pp. including references and indices. $32.50 cloth. Hammond, Norman, ed. Cuello: An Early Maya Community in Belize. Cambridge: Cambridge University Press, 1991. xxi + 260 pp. including references and index. $90.00 cloth.
Intrusion detection based on quantum interference

We present a new method for intrusion detection which is based on the Mach-Zehnder interference effect. This device provides monitored surveillance by continuously measuring the intensity of light collected by a pair of photodetectors.
Die Polymerisation von Silicium-Stickstoffverbindungen

Es werden Methoden zur Darstellung von zwei verschiedenen Typen polymerer Silicium-Stickstoff-Verbindungen beschrieben: a) Ein vernetztes Polydimethylsilazan wird aus Methylcyclosilazanen durch Einwirkung von Ammoniumsalzen (Sauren im Ammonosystem) erhalten. b) Silylamin-Polymere werden durch Reaktion von Dimethyldichlorsilan mit Athylendiamin dargestellt. Die Eigenschaften der Polymeren werden zusammenfassend beschrieben, und der Strukturbeweis mittels ihrer Doppelresonanz-NMR-Spektren geliefert. Die physikalischen Eigenschaften beider Polymertypen werden durch Analyse und Interpretation ihrer Breitband-NMR-Spektren erklart und mit denen linearer Polydimethylsiloxane verglichen.
Do Attitudes and Personality Characteristics Affect Socioeconomic Outcomes? The Case of Welfare Use by Young Women

Objective. We estimate a model of social-psychological determinants of entry into Aid to Families with Dependent Children (AFDC), the primary cash welfare program in the United States until 1996. Methods. Using information from the youngest cohorts of the National Longitudinal Survey of Youth, we estimate logit models of the probability of ever participating in AFDC and hazard models of the timing until first use of AFDC. Results. We find strong associations between welfare use and several attitudes and personality characteristics, but with two exceptions, most of the associations are not robust to the inclusion of exogenous background characteristics. There is consistent, strong evidence that positive attitudes toward school lower the likelihood of using welfare and increase duration until first receipt. Family background and social environment characteristics show strong robust effects. Conclusions. Our results point to relatively weak evidence for the hypothesis that individual attitudes in adolescence have a significant impact on initial welfare receipt.
Introducing an arterial non-injectable connector into clinical practice

The standard arterial system for blood withdrawal provides no impediment to intra-arterial injection [1] and bacterial contamination. We assessed the probability of inadvertent intra-arterial injection, transmission of bacterial contamination and surveyed the nursing staff following introduction of a non-injectable connector (NIC).
Random walks in the space of conformations of toy proteins.

Monte Carlo dynamics of the lattice toy protein of 48 monomers is interpreted as a random walk in an abstract (discrete) space of conformations. To test the geometry of this space, we examine the return probability $P(T)$, which is the probability to find the polymer in the native state after $T$ Monte Carlo steps, provided that it starts from the native state at the initial moment. Comparing computational data with the theoretical expressions for $P(T)$ for random walks in a variety of different spaces, we show that conformation spaces of polymer loops may have nontrivial dimensions and exhibit negative curvature characteristics of Lobachevskii (hyperbolic) geometry.
Measurements of diurnal heat exchange on the Quelccaya Ice Cap, Peruvian Andes

Measurements of the surface heat budget were conducted on an ice cap in the Andes of Southern Peru at 5645 m during an expedition in July 1977. Because of the high surface albedo, net software radiative gain is nearly offset by the longwave loss in the average over the diurnal cycle. The diurnal temperature wave has at the surface an amplitude of about 5°C, and by 50 cm depth this is nearly dampened out. During the day, the shortwave radiative gain is in part used to balance the longwave loss, some heat is stored in the top snow layer and lost by sensible heat transfer to the overlying atmosphere, and the greater part fuels the sublimation. At night, the longwave radiative loss is not completely compensated by heat depletion and downward directed sensible heat transfer. This deficit is made up by the downward transfer of latent heat, resulting in heat release at the surface and deposition. Regarding the mass balance, the nighttime deposition approximately cancels the daytime sublimation. At lower elevations of the ice cap, albedo is much less, allowing larger absorption of solar radiation. As a consequence, more energy is available for ablation. Melting occurs during the day, so that re-freezing and concurrent latent heat release can help to compensate the longwave radiative loss at night.
Testing for association with a case-parents design in the presence of genotyping errors.

Genotyping errors can create a problem for the analysis of case-parents data because some families will exhibit genotypes that are inconsistent with Mendelian inheritance. The problem with correcting Mendelian inconsistent genotype errors by regenotyping or removing families in which they occur is that the remaining unidentified genotype errors can produce excess type I (false positive) error for some family-based tests for association. We address this problem by developing a likelihood ratio test (LRT) for association in a case-parents design that incorporates nuisance parameters for a general genotype error model. We extend the likelihood approach for a single SNP to include short haplotypes consisting of 2 or 3 SNPs. The extension to haplotypes is based on assumptions of random mating, multiplicative penetrances, and at most a single genotype error per family. For a single SNP, we found, using Monte Carlo simulation, that type I error rate can be controlled for a number of genotype error models at different error rates. Simulation results suggest the same is true for 2 and 3 SNPs. In all cases, power declined with increasing genotyping error rates. In the absence of genotyping errors, power was similar whether nuisance parameters for genotype error were included in the LRT or not. The LRT developed here does not require prior specification of a particular model for genotype errors and it can be readily computed using the EM algorithm. Consequently, this test may be generally useful as a test of association with case-parents data in which Mendelian inconsistent families are observed. Genet Epidemiol 26:142–154, 2004. Published 2004 Wiley-Liss, Inc.
Adjuvant chemotherapy in renal leiomyosarcoma

Our encounter with a patient with renal leiomyosarcoma prompted a survey of the world literature in which 84 cases were found. The use of chemotherapy after nephrectomy is advocated since our patient survived more than four years without metastases. The rationale for our chemotherapeutic protocol is discussed.
Evaluation of alternative sampling methods for Salmonella critical control point determination at broiler processing

Several sampling methods have been developed for the detection of Salmonella on broiler carcasses during commercial processing. The present study evaluated three sampling methodologies for sensitivity of Salmonella detection on processed broiler carcasses. Furthermore, the effect of crop removal or chill tank exposure on the frequency of Salmonella recovery was also examined. In two experiments, swab, skin, and carcass rinse samples were compared for sensitivity of Salmonella detection. The results indicated that culture of swabs was less effective (P 0.05) differences were observed in Salmonella recovery from culture of skin or carcass rinse. In two subsequent experiments, skin and carcass rinse samples were found to be equally sensitive in their ability to detect Salmonella. Additionally, the stages of processing between feather and crop removal were observed to cause significant (P < 0.05) increases in Salmonella recovery within an individual flock. Similar increases (P < 0.05) in Salmonella recovery were also observed following crop removal and immediately following immersion chilling in two separate flocks. These results suggest that culture of skin samples obtained from the thoracic inlet region may be a viable alternative to the traditional whole carcass rinse method for sensitivity of Salmonella detection. Furthermore, these experiments provided some evidence that the majority of Salmonella cross-contamination of carcasses prior to immersion chilling occurred following evisceration, with the chill tank potentially providing a major site for cross-contamination between Salmonella-negative and-positive flocks.
A solar energy pilot plant for northern chile

Abstract From the point of view of solar energy, the climatic conditions in the deserts of northern Chile are unusually good. Various industrial solar energy plants have been operated in this region. The historical development, present applications, and extensive research being undertaken in this field by various Chilean universities is described. As part of this research program the author also discusses his projected design for a self-supporting solar energy pilot plant which would produce 4,500 gallons of distilled water per day and generate 50 kw of electricity. Such a plant would have many applications in the arid deserts of northern Chile where the river and well water is too salty for irrigation purposes. Finally, the pilot project is compared with a much larger coastal thermal energy plant designed by A. E. Snyder.
The first step in comprehensively evaluating implementation of an integrated estuarine management plan: Developing evaluation criteria

Abstract This paper defines and develops evaluation criteria for selected portions of the Buzzards Bay Comprehensive Conservation and Management Plan (BBCMP). This evaluative analysis identifies the types of guidance needed for implementing the BBCMP and evaluating the outcomes of that implementation. Thus the paper demonstrates the initial steps in a comprehensive evaluation of the development and implementation of a comprehensive coastal management plan. A central conclusion of this analysis is that the BBCMP's goals, objectives and recommended actions lack the specificity needed to guide its implementation and structure useful evaluations.
The aggregate behavior of branch points: the use of branch point pairing to generate a hidden phase for closed-loop AO

ABSTRACT Recent research has shown that branch points, as they appear in astronomical applications, have a rich collectivebehavior, showing, in particular, that branch point pairs have a well-dened, non-stoichastic velocity, and thatonce a branch point pairs location is measured, it can be tracked in open-loop adaptive optics operation. Theresearch presented here uses this new information as a priori knowledge in closed-loop AO. Specically, analgorithm was developed that measures branch point location and velocity at time t k and then uses this toestimate the phase contribution at time t k + n , giving it an eective memory of where branch points appear andallowing it to determine more accurately between real branch points and noise. The output of the new algorithmis used as a second input to the DM control law. Results of initial closed-loop AO tests will be presented.Keywords: branch point, branch cut, hidden phase, adaptive optics 1. INTRODUCTION The astronomical community relies heavily on images of astronomical objects to conduct science; however, anyimaging done through the atmosphere is degraded due to atmospheric turbulence. As light from a point sourceoutside the atmosphere propagates through the atmosphere, the wave interacts with the density uctuationsin the atmosphere, and the phase of the wave becomes imprinted with the index variations of the atmosphericturbulence. This eect can be corrected through the use of adaptive optics (AO), where the distortion of thewavefront  a single, transverse slice of the incoming wave taken in the pupil plane of the optical system  ismeasured, and the inverse is applied to a deformable mirror (DM). By reecting the incoming wavefront o amirror shaped with the inverse, we can create a at wavefront with no atmospheric distortions [Ref. 1].To measure the distortions in the wavefronts phase, we use a wavefront sensor (WFS), which consists ofboth a device used to measure the phase and an algorithm used to estimate the phase from the raw device data.Although there are many types of wavefront sensors, we use a self-referencing interferometer (SRI) WFS [Ref. 2]in this research to measure the phase and a least mean squares reconstructor (LMS RTR) to estimate the phase.Research has shown that, when observations are taken near-zenith, the LMS RTR is the optimal reconstructor;however, when observations are taken farther o-zenith, an additional component is introduced in the wavefrontphase. This component is composed of circulations and 2 discontinuities  branch points and branch cuts,respectively  that are not sensed by the LMS RTR. The performance of the AO system decreases as a result ofthis additional component because it is not included in the inverse of the phase and, therefore, not corrected bythe DM. To facilitate o-zenith observing, we need a method for accurately detecting, measuring, calculating,and compensating for branch points and branch point phase.
Externalization of the endogenous intracellular lectin of a cellular slime mold

Abstract Intracellular purpurin, the endogenous lectin of Dictyostelium purpureum , has previously been shown to be externalized upon exposure of the cells to anti-purpurin IgG. Externalization of additional purpurin was presumably the consequence of cross-linking of the purpurin molecules already on the cell surface by the IgG, since binding univalent anti-purpurin Fab to the cell surface did not have this effect. In the present report we show that multivalent glycoconjugates that interact with purpurin—including asialo-bovine submaxillary mucin, a bacterial galactan, and bovine albumin derivatized with multiple chains of either lactose or lacto- N -neotetraose—all elicit the externalization of intracellular purpurin. Some of the externalized lectin is bound to the cell surface and some is found in the medium, presumably bound to the glycoconjugates. A similar effect is produced by exposure of the cells to high concentrations of purified purpurin. Several plant lectins, including conA, also have some effect, whereas others are inactive. Since cells in late stages of aggregation have about three times as much cell surface purpurin as those in early stages, this externalization reaction may have significance late in development. The results suggest that intracellular purpurin may be released in response to cross-linking of the endogenous cell surface glycoconjugates that are: (1) already bound to endogenous purpurin; (2) capable of binding purpurin; (3) capable of binding certain other lectins. The intracellular lectin may be a reserve pool, that functions only upon externalization.
Standardized evaluation of simultaneous integrated boost plans on volumetric modulated arc therapy.

The purpose of this paper is to quantify the capability of the RapidArc (RA) planning system to deliver highly heterogeneous doses for simultaneous integrated boost (SIB) in both a phantom and patients. A cylindrical planning target volume (PTV) with a diameter of 6 cm was created in a cylindrical phantom. A smaller boost tumor volume (BTV) in the PTV with varying diameters (0.625?2.5 cm), positions and shapes was also created. Five previously treated patients with brain tumors were included in the study. Original gross tumor volumes (average 41.8 cm3) and PTVs (average 316 cm3) were adopted as the BTV and the PTV in the new plans. 30 Gy was prescribed to the PTV. Doses varying from 35 to 90 Gy were prescribed to the BTV. Both SIB and sequential boost (SEQ) plans were created on RA to meet the prescription. A set of reference plans was also created on the helical tomotherapy (HT) platform. Normalized dose contrast (NDC) and the integral dose were used to evaluate the quality of plans. NDC was defined as the dose contrast between BTV and PTV?BTV, normalizing to the ideal scenario where the contrast is the ratio between prescribed doses to the BTV and PTV. NDC above 90% was observed with BTV dose less than 60 Gy. NDC was minimally affected by the size of BTV but adversely affected by the complexity of the shape of the BTV. In the phantom plans, a peak of NDC was observed with 45 Gy (150% of PTV dose) to the BTV; for BTVs at the center of the PTV, the increase in the integral dose was less than 2% and remained constant for all dose levels in the phantom plans but a linear increase in the integral dose was observed with the HT plans. In the patient plans, an 11% average increase in the integral dose was observed with SIB plans and 60 Gy to the BTV, lower than the 30% average increase in the SEQ plans by RA and 25% by HT. The study showed not only that SIB by RA can achieve superior plans compared with SEQ plans on the same platform and SIB plans on HT, but also the feasibility to optimize prescription dose in a SIB plan. A maximal therapeutic ratio can be achieved with BTV dose 50?100% higher than the PTV dose, depending on the shape and position of the tumor.
Future Caregivers: Projected Family Structures of Older Persons

Elderly persons depend upon spouses and children for emotional, physical, and financial support. In particular, the use of institutional long-term care has been shown to vary by family status. Changes in past and future levels of mortality, fertility, marriage, and divorce will influence the probability that elderly persons of the future have surviving spouses and children. This research uses multiple decrement life tables and component projection methods to project the future family status of elderly persons until the year 2020. The high level of fertility among women during the 1950s will result in greater proportions of future elderly persons having surviving children. Declines in mortality, coupled with increases in rates of marriage, increase the probability that both men and women will have spouses surviving in their old age.
Fiber optic modal domain sensors for monitoring impact-related acoustic shock waves

The applicability of optical fiber modal domain sensors to impact monitoring in aircraft components is studied. This work pulls together a number of scattered ideas from previous research programs onto one working platform, and includes the incorporation of lead-in and lead-out fibers, integrated spatial filtering, a novel fiber termination technique, and an inertial microbender to enhance mode coupling effects. Impacts to both graphite/epoxy composite and metallic specimens were carried out using a unique test apparatus constructed to accommodate a wide variety of measurement conditions. Test results suggest that modal domain sensors can offer quantitative information about the energy associated with a particular impact, as well as its location. Various sensor configurations and signal processing options are discussed, and recommendations for optimized sensing given.© (1994) COPYRIGHT SPIE--The International Society for Optical Engineering. Downloading of the abstract is permitted for personal use only.
Endogenous serotonin release from the dopamine-deficient striatum of the weaver mutant mouse.

In addition to an altered dopaminergic input, the striatum of the weaver mutant mouse (wv/wv) has increased serotonin tissue content and uptake compared to the wild-type mouse (+/+). To gain information regarding the functional status of serotonergic inputs to thewv/wv striatum, endogenous serotonin release fromwv/wv and +/+ striatum was measured under basal conditions as well as in the presence of fenfluramine or elevated concentrations of potassium (K+). Fractional basal release of serotonin from the +/+ striatum was significantly greater than that from thewv/wv striatum. In the presence of K+, evoked release (stimulated release minus basal release) was greater from the +/+ striatum than from thewv/wv striatum. In the presence of fenfluramine, evoked serotonin release was greater from thewv/wv striatum compared to the +/+ striatum. These data are consistent with the involvement of an additional transmitter(s) in modulating serotonin release to a greater extent in thewv/wv than the +/+ striatum. The data on fenfluramine-stimulated serotonin release suggest that the additional serotonin content found in thewv/wv striatum is in a releasable pool but that striatal serotonin release might be attenuated more inwv/wv than in +/+ mice.
Hourly Employee Retention Factors in the Quick Service Restaurant Industry

Abstract Hourly employee retention in the quick service restaurant industry has long been a major area of concern for both operators and multi-unit restaurant decision makers. While numerous studies concentrated on managers' perceptions on why employees leave, few have explored the employees' perceptions on employment characteristics that kept them from changing jobs. The study employed a self-administered questionnaire and asked 233 quick service restaurant employees in the Midwestern region of the United States to rate the importance of and their experience with 20 employment characteristics of their job. The findings revealed that the most important employment characteristics were nice people to work with, humane approach to employees, and hourly wages. In addition, the study showed statistically significant differences between the level of importance and the level of experience attached to 18 out of 20 employment characteristics, which could explain the high turnover and low retention of employees in ...
The stress-strain relation of the plasma membrane of isolated plant protoplasts

Abstract Over periods of up to a few seconds the plasma membrane of isolated rye protoplasts behaves elastically with an area modulus of 230 mN · m −1 . Over longer periods, the area increases with time under large tension and decreases under sufficiently small tension, suggesting that material is incorporated into or depleted from the plane of the membrane.
Genomic Reprogramming and Skin-Like Maturation of Engineered Human Skin Substitutes.

Background: Cultured skin substitutes (CSS) have been evaluated in clinical trials as an adjunctive treatment for large full-thickness burn wounds. Prepared with autologous fibroblasts, keratinocytes, and biopolymers, CSS can provide permanent wound closure upon engraftment to excised burns. The Problem: CSS containing only two cell types are limited in anatomy and physiology compared with normal uninjured skin. Identifying deficiencies in CSS can instruct further tissue engineering advances. Basic/Clinical Science Advances: Expression profiling of CSS during in vitro maturation and after transplantation in vivo with Affymetrix GeneChip® Arrays was used to characterize pathways that are abnormal or deficient in CSS compared with normal human skin. Examination of the large data set generated from microarray expression analysis revealed similarities between healed CSS and normal skin, particularly in expression of genes involved in epidermal differentiation and barrier function. However, deficiencies in sev...
Sex differences in plasma corticosterone release in undisturbed chickens (Gallus gallus) in response to arginine vasotocin and corticotropin releasing hormone.

In birds, two neuropeptides, corticotropin releasing hormone (CRH) and arginine vasotocin (AVT), are major regulators of the hypothalamo-pituitary-adrenal axis (HPA) during the stress response. In birds, however, the relative efficacy of CRH and AVT to stimulate the HPA axis in males and females remains unknown. The purpose of this study was to determine the time course of CORT release following central CRH and AVT administration to male and female chickens. Chickens were fitted with a stainless steel cannula surgically implanted in the lateral ventricle and a catheter chronically inserted in the jugular vein. Birds were housed individually in cages behind a one-way glass partition and unnecessary noise was avoided during the sampling period. Each bird received a single 5.0 μl intracerebroventricular (ICV) injection of either saline (SAL), AVT (10 and 100 pmol), or CRH (10 and 100 pmol). Blood was sampled remotely every 15 min for 2 h and plasma CORT was determined by radioimmunoassay. There was a significant increase in plasma CORT concentration in males injected with 100 pmol AVT beginning at 15 min post-injection through 2 h compared with SAL injected birds. In males, injection of 100 pmol CRH was significantly more effective in releasing CORT compared to an equal molar concentration of AVT or SAL. In females, ICV injection of 100 pmol AVT induced moderate increase in CORT levels. In contrast, 100 pmol CRH significantly increased plasma CORT compared to SAL injected controls but the CORT response was nearly 50% less than that obtained in males.
REPRESENTATION FORMULAS FOR L ∞ NORMS OF WEAKLY CONVERGENT SEQUENCES OF GRADIENT FIELDS IN HOMOGENIZATION

We examine the composition of the L ∞ norm with weakly convergent sequences of gradient fields associated with the homogenization of second order divergence form partial differential equations with measurable coefficients. Here the sequences of coefficients are chosen to model heterogeneous media and are piecewise constant and highly oscillatory. We identify local representation formulas that in the fine phase limit provide upper bounds on the limit superior of the L ∞ norms of gradient fields. The local representation formulas are expressed in terms of the weak limit of the gradient fields and local corrector problems. The upper bounds may diverge according to the presence of rough interfaces. We also consider the fine phase limits for layered microstructures and for sufficiently smooth periodic microstructures. For these cases we are able to provide explicit local formulas for the limit of the L ∞ norms of the associated sequence of gradient fields. Local representation formulas for lower bounds are obtained for fields corresponding to continuously graded periodic microstructures as well as for general sequences of oscillatory coefficients. The representation formulas are applied to problems of optimal material design.
A 26 GHz coplanar stripline-based current sharing CMOS oscillator

A coplanar stripline (CPS) based oscillator topology is introduced that is capable of achieving a low phase noise at extremely high frequencies. This oscillator uses a symmetric current sharing active topology and a high quality factor CPS design in a standard CMOS process without relying on any advanced process features such as the thick analog metal layer option. A 26 GHz prototype oscillator, fabricated in a 0.18 /spl mu/m CMOS process, achieves a phase noise of -110 dBc/Hz at 1 MHz offset frequency, while drawing a current of 3.36 mA from a 1.8 V supply.
Induction of Cyclin-Dependent Kinase 5 in the Hippocampus by Chronic Electroconvulsive Seizures: Role of ΔFosB

The transcription factor DeltaFosB is induced in the hippocampus and other brain regions by repeated electroconvulsive seizures (ECS), an effective antidepressant treatment. The unusually high stability of this protein makes it an attractive candidate to mediate some of the long-lasting changes in the brain caused by ECS treatment. To understand how DeltaFosB might alter brain function, we examined the gene expression profiles in the hippocampus of inducible transgenic mice that express DeltaFosB in this brain region by the use of cDNA expression arrays that contain 588 genes. Of the 430 genes detected, 20 genes were consistently upregulated, and 14 genes were downregulated, by >50%. One of the upregulated genes is cyclin-dependent kinase 5 (cdk5). On the basis of its purported role in regulating neuronal structure, we studied directly whether cdk5 is a true target for DeltaFosB. Upregulation of cdk5 immunoreactivity in the hippocampus was confirmed by Western blotting in the DeltaFosB-expressing transgenic mice as well as in rats treated chronically with ECS. Chronic ECS treatment also increased, in the hippocampus, the phosphorylation state of tau, a microtubule-associated protein that is a known substrate for cdk5. A 1.6 kb fragment of the cdk5 promoter was cloned, and activity of the promoter was found to be increased after overexpression of DeltaFosB in cell culture. Moreover, mutation of the single consensus activator protein-1 site contained within the cdk5 promoter fragment completely abolished activation of the promoter by DeltaFosB. Together, these results suggest that cdk5 is one target by which DeltaFosB produces some of its physiological effects in the hippocampus and thereby mediates certain long-term consequences of chronic ECS treatment.
Decoding spherical codes for the Gaussian channel

A decoding algorithm for permutation codes that is equivalent to maximum-likelihood decoding, but less complex than the correlation decoder, is presented. A general construction for iteratively maximum-likelihood decodable (IMLD) codes is proved and used to construct IMLD codes for every dimension n. D. Slepian (1965) defined permutation modulation codes and presented an efficient algorithm for their decoding. Slepian's decoding scheme is one of the principal components of the permutation code decoding algorithm presented. >
A Proposal for the Next Generation Low-Cost, High QoS and Capacity, Fair, and Adaptable Group Division Multiple Optical Access Networks (GDMOAN)

Present-day optical networks suffer from high-cost, low-QoS, low-capacity, low-scalability, unfairness, inflexibility, and short-distance. Group division multiple optical access (GDMOA) is the next-generation optical-access-network technology that diminishes these drawbacks with feedback-and prediction-based bandwidth allocation.
Global climate change and its impact on disease embedded in ecological communities

We present the techniques of qualitative analysis of complex communities and discuss the impact of climate change as a press perturbation. In particular, we focus on the difficult problem of disease and parasites embedded in animal communities, notably zoonotic diseases. Climate change can potentially affect population densities of hosts and vectors, as well as their life expectancy. Recent advances may provide insight in predicting change in risk of zoonotic disease following climate shifts. We conclude that the impact of change on ecological communities can be profound but subtle, complex, and ambiguous, even under basic mathematical assumptions about the structure of a community when in equilibrium.
Neglected ethical issues in biobank management: Results from a U.S. study

The empirical literature on the ethical, legal, and social implications (ELSI) of biobanking has almost entirely relied on the perspectives of those outside of biobanks, such as the general public, researchers, and specimen contributors. Little attention has been paid to the perspectives and practices of those who operate biobanks. We conducted a study of U.S. biobanks consisting of six in-depth case studies and a large online survey (N = 456), which was developed from the case study results. The case studies included qualitative interviews with a total of 24 personnel. Both interview and survey questions focused on how biobanks operate, and what policies and practices govern their relationships with specimen contributors and the researchers who use the specimens. Analysis revealed unexpected ethical dilemmas embedded in those policies and practices that highlight a need for practical planning. In this paper, we review three issues seldom explored in the ELSI literature: 1. the discrepancy between biobankers’ hope that the bank will exist “permanently” and the fact that funding is limited; 2. the lack of planning for what will happen to the specimens if the bank closes; and 3. the concern that once collected, specimens may be underutilized. These dilemmas are missing from current public representations of biobanks, which instead focus on the intrinsic value in storing specimens as essential to the advancement of translational research. We argue that attention to these issues is important for biobanking, and that greater transparency of these policies and practices will contribute to promoting public trust in biobanks.
The evolution of polyandry II: post–copulatory defenses against genetic incompatibility

Fundamental to the recentlyproposed hypothesis that females mate with more than one male as a hedge against genetic incompatibility is the premise that mechanisms are available to polyandrous femal...
Biologically active ester derivatives as potent inhibitors of the soluble epoxide hydrolase

Substituted ureas with a carboxylic acid ester as a secondary pharmacophore are potent soluble epoxide hydrolase (sEH) inhibitors. Although the ester substituent imparts better physical properties, such compounds are quickly metabolized to the corresponding less potent acids. Toward producing biologically active ester compounds, a series of esters were prepared and evaluated for potency on the human enzyme, stability in human liver microsomes, and physical properties. Modifications around the ester function enhanced in vitro metabolic stability of the ester inhibitors up to 32-fold without a decrease in inhibition potency. Further, several compounds had improved physical properties.
Spin-polarized quasiparticle transport in cuprate superconductors

The effects of spin-polarized quasiparticle transport in superconducting YBa 2 Cu 3 O 7 - Φ (YBCO) epitaxial films are investigated by means of current injection into perovskite ferromagnet-insulator-superconductor (F-l-S) heterostructures. These effects are compared with the injection of simple quasiparticles into control samples of perovskite nonmagnetic metal-insulator-superconductor (N-I-S). Systematic studies of the critical current density (J c ) as a function of the injection current density (J i n j ), temperature (T), and the thickness (d) of the superconductor reveal drastic differences between the F-I-S and N-I-S heterostructures. with strong suppression of J c and a rapidly increasing characteristic transport length near the superconducting transition temperature T c only in the F-I-S samples The temperature dependence of the efficiency (η≡ΔJ c /J i n j ; ΔJ c : the suppression of critical current due to finite J i n j ) in the F-I-S samples is also in sharp contrast to that in the N-I-S samples, suggesting significant redistribution of quasiparticles in F-I-S due to the longer lifetime of spin-polarized quasiparticles. Application of conventional theory for nonequilibrium superconductivity to these data further reveal that a substantial chemical potential shift μ* in F-I-S samples must be invoked to account for the experimental observation, whereas no discernible chemical potential shift exists in the N-I-S samples, suggesting strong effects of spin-polarized quasiparticles on cuprate superconductivity. The characteristic times estimated from our studies are suggestive of anisotropic spin relaxation processes, possibly with spin-orbit interaction dominating the c-axis spin transport and exchange interaction prevailing within the CuO 2 planes. Several alternative scenarios attempted to account for the suppression of critical currents in F-I-S samples are also critically examined, and are found to be neither compatible with experimental data nor with the established theory of nonequilibrium superconductivity.
Management of perioperative nutrition support.

Purpose of review Perioperative nutrition has been extensively studied, but numerous questions remain unanswered. This review focuses on new developments in nutrient delivery in the immediate perioperative period. Issues specifically addressed include which patients are most likely to benefit from perioperative nutritional supplementation, and the optimal route, timing, and quantity of nutrient delivery. Recent findings Visceral proteins, particularly albumin, play an important role in nutritional and perioperative risk assessment. Although the recommendation to use the enteral route for delivery of nutrition whenever possible is clear, the cautious introduction of enteral feeds in the labile group of patients with circulatory failure is essential. Preoperative use of immune-modulating enteral formulas, preoperative carbohydrate loading, and the concept of early enteral feeding are important developments. Supplementary arginine, glutamine, and omega-3 fats play a potential role in nutritional management, as does 'permissive' hypocaloric feeding. Summary The particulars of nutritional support for perioperative and critically ill patients remain controversial. Recent studies addressing specific issues in this diverse discipline perhaps raise more questions than are answered. However, each new contribution to the literature brings us closer to an understanding of optimal nutritional management in the metabolically stressed patient.
High-resolution measurements with a spaceborne pencil-beam scatterometer using combined range/Doppler discrimination techniques

Conically scanning pencil-beam scatterometer systems, such as the SeaWinds radar, constitute an important class of instruments for spaceborne climate observation. In addition to ocean winds, scatterometer data are being applied to a wide range of land and cryospheric applications. A key issue for future scatterometer missions is improved spatial resolution. Pencil-beam scatterometers to date have been real-aperture systems where only range discrimination is used, resulting in a relatively coarse resolution of approximately 25 km. In this paper, the addition of Doppler discrimination techniques is proposed to meet the need for higher resolution. The unique issues associated with the simultaneous application of range and Doppler processing to a conically scanning radar are addressed, and expressions for the theoretical measurement performance of such a system are derived. Important differences with side-looking imaging radars, which also may employ Doppler techniques, are highlighted. Conceptual design examples based on scatterometer missions of current interest are provided to illustrate this new high-resolution scatterometer approach. It is shown that spatial resolution of pencil-beam scatterometer systems can be improved by an order of magnitude by utilizing combined range/Doppler discrimination techniques, while maintaining the wide-swath and constant incidence angle needed for many geophysical measurements.