cssi/SciSciGPT-SciSciNet huggingface dataset:
The interplay between Bag-1, Hsp70, and Hsp90 reveals that inhibiting Hsp70 rebinding is essential for Glucocorticoid Receptor activity

Abstract The glucocorticoid receptor (GR), like many signaling proteins requires Hsp90 for sustained activity. Previous biochemical studies revealed that the requirement for Hsp90 is explained by its ability to reverse Hsp70-mediated inactivation of GR through a complex process requiring both cochaperones and Hsp90 ATP hydrolysis. How ATP hydrolysis on Hsp90 enables GR reactivation is unknown. The canonical mechanism of client release from Hsp70 requires ADP:ATP exchange, which is normally rate limiting. Here we show that independent of ATP hydrolysis, Hsp90 acts as an Hsp70 nucleotide exchange factor (NEF) to accelerate ADP dissociation, likely coordinating GR transfer from Hsp70 to Hsp90. As Bag-1 is a canonical Hsp70 NEF that can also reactivate Hsp70:GR, the impact of these two NEFs was compared. Simple acceleration of Hsp70:GR release was insufficient for GR reactivation as Hsp70 rapidly re-binds and re-inactivates GR. Instead, inhibition of GR re-inactivation by Hsp70 is critical. This can be accomplished by high non-physiological Bag-1 concentrations, which also inhibit Hsp70:ATP binding. In contrast, in an ATP-hydrolysis dependent process, Hsp90 plays a unique role by kinetically partitioning GR into a state that can bind ligand, but is protected from Hsp70 inactivation, thus allowing GR to be activated by its ligand but still able to re-enter the chaperone cycle. At physiologic concentrations, Bag-1 works synergistically with Hsp90 to accelerate the first rate-limiting step in GR reactivation. The net effect is that the chaperone machinery cyclically dictates the on and off rates for GR ligand, providing a timer controlling the persistence of activated GR. Significance Statement The glucocorticoid receptor (GR) is an essential transcription regulatory factor. Like many signaling proteins, GR activity is regulated by two essential molecular chaperones: Hsp90 and Hsp70. Functioning like a toggle switch, Hsp70 first inactivates GR, and then Hsp90 reactivates GR in an Hsp90 ATP hydrolysis dependent manner. Here, an intricate set of biochemistry experiments uncover fundamental principles governing how these chaperone systems collaboratively regulate GR activity. While Hsp90 promotes GR release from Hsp70 by modulating Hsp70’s nucleotide state, this occurs independently of Hsp90 ATP hydrolysis. Instead, ATP hydrolysis on Hsp90 facilitates a second essential reactivation step resulting in an Hsp90-bound GR state that protects GR from Hsp70 re-inactivation. A kinetic partitioning model best describes chaperone modulation of GR’s activity.
Research on Neutral Voltage Offset and Its Influencing Factors of 20kV Small Resistance Grounding System

With the continuous development of urban power grids, the application of 20 kV all-cable distribution networks is becoming more and more common. The adoption of cables ensure the reliability of the power supply, but also cause the single-phase grounding capacitor current to easily exceed hundreds of amps, which seriously endangers the safe operation of power distribution equipment. Existing researches are mostly based on theoretical analysis, it is believed that low resistance at the neutral point can reduce the system overvoltage level, however, during actual operation, it is found that the abnormal transient voltage and current of some distribution networks cause frequent tripping of the line, and even the phenomenon that the transient voltage and current of the fault phase increases simultaneously during the transient process is observe. Based on the actual failure of a 20kV distribution network, this paper analyzes the single-phase grounding fault of a large-capacity current system. The simulation method is used to reproduce the transient voltage and current waveforms during the fault, extract the characteristic quantities of the simulated waveforms and compare them with the recorded waveforms. It is found that arc grounding is the cause of the failure of the system. By theoretically calculating the voltage offset of the stable grounding process, it is considered that the offset level and recovery speed of the neutral point voltage during the arc grounding flashover are the decisive factors for the arc grounding overvoltage level. Based on this, the influence of factors such as system scale, neutral resistance and grounding resistance on the transient overvoltage of a small resistance grounding system is studied.
A Key to Transforming a Nursing Curriculum: Integrating a Continuous Improvement Simulation Expansion Strategy

IntroductionChanges in nursing, health care, and education warrant continued pedagogical innovations. Faculty are challenged to develop many innovative strategies in the clinical and simulation lab...
Social Network Analysis of the Effects of a Social Media-Based Weight Loss Intervention Targeting Adults of Low Socioeconomic Status: Single-Arm Intervention Trial.

Background Obesity is a known risk factor for cardiovascular disease risk factors, including hypertension and type II diabetes. Although numerous weight loss interventions have demonstrated efficacy, there is considerably less evidence about the theoretical mechanisms through which they work. Delivering lifestyle behavior change interventions via social media provides unique opportunities for understanding mechanisms of intervention effects. Server data collected directly from web-based platforms can provide detailed, real-time behavioral information over the course of intervention programs that can be used to understand how interventions work. Objective The objective of this study was to demonstrate how social network analysis can facilitate our understanding of the mechanisms underlying a social media-based weight loss intervention. Methods We performed secondary analysis by using data from a pilot study that delivered a dietary and physical activity intervention to a group of participants via Facebook. We mapped out participants' interaction networks over the 12-week intervention period and linked participants' network characteristics (eg, in-degree, out-degree, network constraint) to participants' changes in theoretical mediators (ie, dietary knowledge, perceived social support, self-efficacy) and weight loss by using regression analysis. We also performed mediation analyses to explore how the effects of social network measures on weight loss could be mediated by the aforementioned theoretical mediators. Results In this analysis, 47 participants from 2 waves completed the study and were included. We found that increases in the number of posts, comments, and reactions significantly predicted weight loss (β=-.94, P=.04); receiving comments positively predicted changes in self-efficacy (β=7.81, P=.009), and the degree to which one's network neighbors are tightly connected with each other weakly predicted changes in perceived social support (β=7.70, P=.08). In addition, change in self-efficacy mediated the relationship between receiving comments and weight loss (β=-.89, P=.02). Conclusions Our analyses using data from this pilot study linked participants' network characteristics with changes in several important study outcomes of interest such as self-efficacy, social support, and weight. Our results point to the potential of using social network analysis to understand the social processes and mechanisms through which web-based behavioral interventions affect participants' psychological and behavioral outcomes. Future studies are warranted to validate our results and to further explore the relationship between network dynamics and study outcomes in similar and larger trials.
Perceived impacts of a Medicaid rebalancing initiative to increase home- and community-based services.

Objective To assess governmental and nongovernmental stakeholders' perceived impacts of a Medicaid home- and community-based services (HCBS) rebalancing initiative, the Balancing Incentive Program (BIP). Data sources Governmental stakeholders (Medicaid administrators) and nongovernmental stakeholders (service providers and consumer advocates) (n = 30) from eight states that participated in BIP. Study design We conducted key informant interviews. Data collection Interviews followed a semi-structured guide and were professionally transcribed. We thematically coded transcripts using an iterative codebook with a priori and emergent codes. Principal findings Stakeholders reported that BIP participation had a range of impacts on the HCBS ecosystem, often beyond the mandated structural reforms. BIP activities were believed to have changed the culture of HCBS in some states, for example, at the level of state administration or in the provision of HCBS to consumers. Stakeholders also described significant improvements in cross-stakeholder relationships and communication, for example, in the context of troubleshooting consumers' unmet needs or improvements in the states' responsiveness to providers' inquiries. Stakeholders believed that within-state data harmonization undertaken through Core Standardized Assessment (CSA) was a positive impact of BIP, particularly with regard to its utility for administrative data, care planning, and patient-centeredness. Two stakeholders also voiced concerns regarding the validity of spending-based rebalancing metrics. The impacts that stakeholders attributed to BIP may help create a more sustained rebalancing environment through their changes to the ecosystem, including infrastructure upgrades, data harmonization, collaboration across stakeholders and agencies, more patient-centeredness, and greater recognition of HCBS. Conclusions Our findings highlight additional BIP impacts to monitor over the longer term and to consider in evaluations of future rebalancing efforts. Some potential impacts of BIP are more readily quantified (e.g., HCBS spending), while others are less likely to be formally assessed (e.g., improved stakeholder cooperation). These latter impacts are likely instrumental to future rebalancing efforts.
Full-Time Cardiac Intensive Care Unit Staffing by Heart Failure Specialists and its Association with Mortality Rates.

Background Cardiac intensive care units (CICUs) serve medically complex patients with multi-organ dysfunction. Whether a CICU staffed full time by heart failure (HF) specialists is associated with decreased mortality is unclear. Methods and results Retrospective review of consecutive CICU admissions from January 1, 2012 to Dec 31, 2016 was performed. In January 2014, the CICU changed from an open unit staffed by any cardiologist to a closed unit managed by HF specialists. Patients' baseline characteristics were determined, and a multivariate regression analysis was performed to ascertain CICU mortality. Baseline severity of illness was higher in the closed/HF specialist CICU model (p Conclusion Transition to a closed unit model staffed with a dedicated HF specialist is associated with lower CICU mortality.
Critical Race Feminism and Afrocentricity

This chapter provides a detailed discussion on the theoretical framework and background for the book and the study on Ethiopian immigrants in the U.S. This chapter develops critical race feminism (CRF) and Afrocentricity as theoretical lens for our discussion. Additionally, using CRF and Afrocentricity, the chapters provide cultural context for Ethiopia and Ethiopians as immigrants’ experiences. It also discusses racial and ethnic relations, identity development, and cultural conflicts in the U.S.
Evidence for rectus extraocular muscle pulleys in rodents.

Purpose Extraocular rectus muscle (EOM) pulleys are important determinants of orbital biomechanics in humans. In this study, the authors evaluated orbital connective tissue morphology, specifically characterizing rectus muscle pulleys, in the rat, a species with laterally placed eyes, afoveate vision, and a less complex visuomotor repertoire than primates. Methods Adult rat orbits were paraffin processed and serially sectioned for histochemical and immunohistochemical staining. Frozen sections of enucleated globes with intact EOMs and associated connective tissue were also studied with myosin immunohistochemistry and histochemistry for the mitochondrial enzyme, nicotinamide adenine dinucleotide (NADH)-tetrazolium reductase, to delineate the orbital layer relationship with the pulley tissue. Results Focal condensations of collagenous connective tissue were found in relationship to the rectus muscles in the equatorial Tenon's fascia, similar to those described as human recti muscle pulleys. The fibroelastic pulley rings were coupled to adjacent EOM pulleys by bands containing collagen and elastin. The coupling of pulleys to the orbital walls was significantly less than that previously described in humans. As in humans, there was a dual insertion of rodent rectus muscles, with the orbital layer inserting on the muscle pulley and the global layer attaching to the sclera. Conclusions The data support the presence of structures in the rat orbit that are the morphologic equivalent of the human rectus pulley system. Although rodent and human pulleys were similar in many respects, there were species-specific properties that may relate to established differences in orbital anatomy and/or visuomotor behavior. These data extend the rectus muscle pulley concept to rodents and may provide insight into pulley structure-function relationships.
Rethinking the ethics of incentives

Incentives are typically conceived as a form of trade, and so voluntariness appears to be the only ethical concern. As a consequence, incentives are often considered ethically superior to regulations because they are voluntary rather than coercive. But incentives can also be viewed as one way to get others to do what they otherwise would not; that is, as a form of power. When incentives are viewed in this light, many ethical questions arise in addition to voluntariness: What are the responsibilities of the powerful in using incentives? Can incentives be manipulative or exploitative, even if people are free to refuse them? Like all other forms of power, incentives can be abused. This paper develops criteria for distinguishing their legitimate from their illegitimate uses, viz. legitimacy of purpose, voluntariness, and effect on character. The criteria are then applied to three cases: plea bargaining, recruiting medical research subjects, and motivating children to learn. Thinking of incentives in terms of ...
Spatial analysis of gastroschisis in the national birth defects prevention study

Background Gastroschisis is a birth defect where loops of bowel are protruding from the abdominal wall at birth. Previous research has suggested that gastroschisis cases can occur in clusters. The objective of this study was to identify if there were areas of elevated gastroschisis risk using data from the National Birth Defects Prevention Study (NBDPS), 1997 through 2007.
Hageman Trait (Factor XII Deficiency): A Probable Second Genotype Inherited as an Autosomal Dominant Characteristic

A family is described in which Hageman trait appeared to be inherited in an autosomal dominant manner in contrast to previously reported families in which the disorder behaves as an autosomal recessive characteristic. Immunologic studies suggested that the molecular defect was similar to that of the autosomal recessive form and consisted of deficiency of antigens related to Hageman factor.
Ecology of a tidal marsh corixid, Trichocorixa verticalis (Insecta, Hemiptera)

The high marsh panne ecosystem at Adam's Point, N. H. provides a particular opportunity for holistic, yet autecological approach to the natural history of Trichocorixa verticalis var. sellaris (Corixidae). This area was dominated by physical and chemical factors associated with highly variable salinities (1 to 160‰) and temperatures (−1 to 40°C) caused by irregular tidal flooding and neap tidal dry periods. Trichocorixa verticalis reach a maximum density of 26,914/m2 (x = 3,909.6/m2) in open shallow pannes, where eggs hatch in staggered sequence, allowing population replenishment after drought and reflooding. Winter eggs hatched between salinities of 0 to 30‰ at 20°C and 0 to 20‰ at 10°C. Summer eggs hatched between salinities of 0 to 55‰ at variable temperatures (20 to 36°C). All instars showed a similar higher summer and lower fall tolerance; immatures were more tolerant than adults. Body molt measurements of the 6 instars are given here. Aside from being herbivores and detritivores, T, verticalis feed on chironomid larvae and oligochaetes. They are food for invertebrates and vertebrates, and provide substantial food for migratory shorebirds.
Inbreeding Depression in the Red-Legged Partridge

Abstract Inbred lines were established in 1967 (Experiment 1) and 1978 (Experiment 2). They were continued for one and two additional generations of full-sib matings in the first and second experiments, respectively. In both experiments, alternating periods of stimulatory and nonstimulatory light were used to induce egg production in two 15-week production periods. In Experiment 1, 10 of 22 full-sib lines were lost after only one generation of full-sib mating. Of the 29 initial full-sib lines established in Experiment 2, only 6 survived two generations of full-sib inbred matings (F = .375). Egg weight, sexual maturity, and body weight were depressed significantly (P The results indicate that establishment and maintenance of highly inbred lines of partridge will require selection of matings from families having superior reproductive traits as well as alternating cycles of inbreeding such as by full-sib mating with crosses of unrelated inbred lines.
Microcomputer-Based Nonlinear Structural Analysis Of Transmission Line Systems

Until recently, calculations needed for the structural design of transmission lines required access to large computers. Advances in both microcomputer capabilities and in nonlinear structural analysis techniques indicate that it is no longer necessary, nor often desirable, to use mainframe or mini computers. The facts are demonstrated by several examples of complex systems (guyed lattice tower, interaction between structures of a flexible system, H-frame, sagtension behavior, etc.). Many transmission line structures or subsystems exhibit pronounced nonlinear behavior. Four sources of nonlinearities are common: 1) geometric nonlinearity of the relationship between cable sag and tension (even if the cable remains elastic), 2) geometric nonlinearity, or so called P - ?? effect, caused by support displacement (common in poles, H-frames or guyed lattice structures), 3) nonlinear stress-strain relationship of a cable (especially for a conductor where creep and permanent stretching occur), and 4) local nonlinear behavior of a component (plastic deformation of a beam element, buckling of a compression member in a lattice ``tension only'' bracing system, etc.). Because of these effects, nonlinear analysis techniques should be available to the transmission line designer. The paper demonstrates that: 1) the right combination of structural element and solution strategy permits the solution of virtually any structural transmission line problem and 2) the solution can be obtained efficiently on the current generation of microcomputers. The first part of the paper discusses how a microcomputer should be used in typical analysis-design applications.
Comparisons of the Hückel and Pariser-Parr-Pople-type MO methods: Closed forms for SCF charge distributions and bond orders

Analysis of the similarities and differences among the Huckel and Pariser-Parr-Pople-type methods is extended mainly through development for special molecular cases of closed form expressions for the self-consistent wavefunctions. By means of these expressions the various contributions of terms in the Hamiltonian to charge densities, bond orders and other related quantities may be compared term-by-term among the methods. Results on several direct observables, e.g. ionization potentials, electron affinities, bond lengths are similarly dissected. Simplified procedures for generation of the self-consistent charge densities and bond orders from their zeroth-order counterparts in the PPP method are detailed.
Incidence, predictors, and outcomes of post-percutaneous coronary intervention nephropathy in patients with diabetes mellitus and normal baseline serum creatinine levels.

Diabetes mellitus is an independent predictor of nephropathy after percutaneous coronary intervention (PCI). The outcomes of patients with diabetes with normal baseline serum creatinine who undergo PCI remain underevaluated. The aim of the present study was to assess the incidence, outcomes, and correlates of post-PCI nephropathy in this subset. The study cohort consisted of 570 patients with diabetes with normal serum creatinine (≤1.3 mg/dl) who underwent PCI from August 2004 to December 2006. Patients aged >75 years and those presenting with either acute myocardial infarctions or cardiogenic shock were excluded. Post-PCI nephropathy was defined as a ≥25% increase in baseline creatinine. The study end points were post-PCI nephropathy and major adverse cardiac events at 6 months. Logistic regression was performed to identify independent predictors. Post-PCI nephropathy occurred in 70 patients (incidence 12.3%). These patients were more likely to be women (55.7% vs 35.5%, p = 0.001) and to have histories of congestive heart failure (24.2% vs 14.7%, p = 0.048). Entry-site complications (hematoma, pseudoaneurysm) and the need for blood transfusion (16.7% vs 1.7%, p <0.001) were more common in this group. In-hospital mortality (8.6% vs 0.2%, p <0.001) and length of stay (4.51 ± 5.2 vs 2.23 ± 2.9 days, p <0.001) were significantly higher in the group with post-PCI nephropathy. No study patient required dialysis. At 6 months, major adverse cardiac events were markedly higher in patients with post-PCI nephropathy (21.4% vs 6.0%, p <0.001), driven by death and revascularization. Independent predictors of post-PCI nephropathy were lower body mass index and blood transfusion. Post-PCI nephropathy independently predicted major adverse cardiac events (hazard ratio 4.3, 95% confidence interval 2.1 to 8.6, p <0.001). In conclusion, post-PCI nephropathy occurred in 12.3% of patients with diabetes with normal baseline serum creatinine and carried a significant detrimental impact on prognosis. The requirement for blood transfusions was the strongest correlate identified.
Cortical reinstatement and the confidence and accuracy of source memory.

Cortical reinstatement refers to the overlap between neural activity elicited during the encoding and the subsequent retrieval of an episode, and is held to reflect retrieved mnemonic content. Previous findings have demonstrated that reinstatement effects reflect the quality of retrieved episodic information as this is operationalized by the accuracy of source memory judgments. The present functional magnetic resonance imaging (fMRI) study investigated whether reinstatement-related activity also co-varies with the confidence of accurate source judgments. Participants studied pictures of objects along with their visual or spoken names. At test, they first discriminated between studied and unstudied pictures and then, for each picture judged as studied, they also judged whether it had been paired with a visual or auditory name, using a three-point confidence scale. Accuracy of source memory judgments – and hence the quality of the source-specifying information – was greater for high than for low confidence judgments. Modality-selective retrieval-related activity (reinstatement effects) also co-varied with the confidence of the corresponding source memory judgment. The findings indicate that the quality of the information supporting accurate judgments of source memory is indexed by the relative magnitude of content-selective, retrieval-related neural activity.
An information ‐ expectation framework for decisions under uncertainty

Despite being in existence for many decades, normative decision theory has not become a commonly used tool for real-world decisions. This paper considers the reasons for this situation and suggestions for circumventing them. The main suggestion involves a two-stage framework in terms of the information available to the decision maker and his/her expectations under the available acts. This framework is well suited for decisions with incomplete structure, which is typical of real decision situations. Within this framework a specific multiplicative model is also discussed.
The conditions of municipal employment in Chicago

In this article Professor White summarizes the results of a careful study of hte municipal employment conditions in Chicago.
Entanglement spectrum classification of C n -invariant noninteracting topological insulators in two dimensions

We study the single-particle entanglement spectrum in 2D topological insulators which possess $n$-fold rotation symmetry. By defining a series of special choices of subsystems on which the entanglement is calculated, or real space cuts, we find that the number of protected in-gap states for each type of these real space cuts is a quantum number indexing (if any) nontrivial topology in these insulators. We explicitly show that the number of protected in-gap states is determined by a ${Z}^{n}$ index $({z}_{1},...,{z}_{n})$, where ${z}_{m}$ is the number of occupied states that transform according to $m$th one-dimensional representation of the ${C}_{n}$ point group. We find that for a space cut separating $1/p$th of the system, the entanglement spectrum contains in-gap states pinned in an interval of entanglement eigenvalues $[1/p,1\ensuremath{-}1/p]$. We determine the number of such in-gap states for an exhaustive variety of cuts, in terms of the ${Z}^{n}$ index. Furthermore, we show that in a homogeneous system, the ${Z}^{n}$ index can be determined through an evaluation of the eigenvalues of point-group symmetry operators at all high-symmetry points in the Brillouin zone. When disordered $n$-fold rotationally symmetric systems are considered, we find that the number of protected in-gap states is identical to that in the clean limit as long as the disorder preserves the underlying point-group symmetry and does not close the bulk insulating gap.
A half plane and a strip with an arbitrarily located crack

A technique is presented for dealing with the problem of an elastic domain containing an arbitrarily oriented internal crack. The problem is formulated as a system of integral equations for a fictitious layer of body forces imbedded in the plane along a closed smooth curve encircling the original domain. The problems of a half plane with a crack in the neighborhood of its free boundary and of an infinite strip containing a symmetrically located internal crack with an arbitrary orientation are considered as examples. In each case the stress intensity factors are computed and are given as functions of the crack angle.
Statistical and analytical models for roof components in existing light-framed wood structures

Residential wood-framed construction failures account for the majority of economic losses following hurricanes. A common failure in these constructions during high wind events is loss of roof sheathing, especially in corner areas. Less common perhaps, but usually catastrophic, is the failure of the roof-to-wall connections in these structures. The main objective of the current research project is to evaluate the in-situ capacity of roof-to-wall connections and sheathing to rafter fasteners in light-framed wood constructions. The unique opportunity provided by Clemson University to access four residential structures located within a residential complex enabled the collection of perishable yet statistically significant data on the strengths of existing residential structures. The uplift capacities of 100 roof-to-wall toenail connections and 34 plank sheathing units were evaluated from field and laboratory tests. Realizing the key role of probability distributions in developing fragility estimates and loss prediction models, distribution fits and parameters for these structural components are postulated. One conclusion drawn is that the uplift capacities of two and three nail connections are best described by a lognormal distribution. The initial stiffness and the vertical displacement at peak load of both two nail and three nail connections follow a normal and Weibull distribution respectively. The uplift capacity of plank sheathing follows a lognormal distribution. An analytical model designed to approximate the uplift behavior of toenail connections is developed to facilitate modeling of roof systems. These probabilistic and analytical models developed by this study allow for the performance of detailed reliability based studies on light-framed wood roof structures.
Terrible Triad Fracture-Dislocations of the Elbow

Management of terrible triad injuries of the elbow has improved in the last 2 decades based on an understanding of injury patterns, fracture morphology, and management pitfalls. But some intimidation with these injuries remains, in part because some of the surgical techniques are challenging and because there is still debate about certain steps in surgery and choices in management. This article highlights important aspects of the care of terrible triad injuries to clarify the anatomy and patho-physiology, to highlight pitfalls of treatment, and to point out areas that might benefit from innovation.
Office Dilation of the Female Urethra: A Quality of Care Problem in the Field of Urology

Purpose: Historically dilation of the female urethra was thought to be of value in the treatment of a variety of lower urinary tract symptoms. Subsequent work has more accurately classified these complaints as parts of various diseases or syndromes in which scant data exist to support the use of dilation. Yet Medicare reimbursement for urethral dilation remains generous and we describe practice patterns regarding female urethral dilation to characterize a potential quality of care issue.Materials and Methods: Health care use by females treated with urethral dilation was compiled using a complementary set of databases. Data sets were examined for relevant inpatient, outpatient and emergency room services for women of all ages.Results: Female urethral dilation is common (929 per 100,000 patients) and is performed almost as much as treatment for male urethral stricture disease. Approximately 12% of these patients are subjected to costly studies such as retrograde urethrography. The overall national costs for...
Sprint training improves contractility in postinfarction rat myocytes: role of Na+/Ca2+ exchange

Previous studies in adult myocytes isolated from rat hearts 3–9 wk after myocardial infarction (MI) demonstrated abnormal contractility and decreased Na+/Ca2+ exchanger (NCX1) activity. In addition...
Application of simultaneous purging and solvent extraction technique for flavour monitoring of natural products

Abstract A newly developed simultaneous purging and solvent-extraction apparatus was used to investigate variations of volatiles formed from natural bananas during ripening periods. Five alkylacetates and five alkylbutyrates, which give characteristic flavours to banana, were chosen for flavour monitoring during banana ripening. Their formation increased during the ripening period. After 10 days, ester formation reached a maximum at the onset of the fruit's senescence period. Three alkyl alcohols increased steadily in concentration for 5 days and plateaued until the late senescence stages. Fresh celery volatiles were also collected using the same apparatus in order to investigate its possible application for collecting headspace volatiles of fresh vegetables. The compounds isolated and identified in the headspace sample from celery were 14 terpenes and two aromatic compounds.
Promoting reading comprehension with the use of technology

Abstract The research presented here explores the impact of two web-based applications (an interactive, multimedia literacy software and a digital process portfolio) on early elementary students' reading comprehension. Two studies were conducted during the 2010–2011 and the 2011–2012 school years, targeting 26 teachers from elementary schools (grades 1–2), and their students ( N = 517) from six English school boards in Quebec, Canada. Analyses of covariance showed that students using both tools performed significantly better ( p
Comparison of Day and Evening Crop Rescue Strategies to Control Black Cutworm (Lepidoptera: Noctuidae) Larvae in Corn

Three experiments were conducted during the 1978 and 1979 growing seasons to compare the efficacy of crop rescue applications made during the day and evening. We used both natural and induced infestations, and we used two insecticides, toxaphene and chlorpyrifos. Evening crop rescue applications that coincided with a thermal inversion were consistently better than corresponding diurnal applications; evening and day applications were equally good in the absence of a thermal inversion. Additional information obtained from this study dealt with the relationships between Agrotis ipsilon (Hufnagel) damage, plant stand, yield, and larval captures. Significant curvilinear relationships were found for plant stand with yield and yield with A. ipsilon larval captures. These data suggested that an average of 11.5 trapped larvae per 2.6 m2 area could completely destroy corn stands in small plots surrounded by metal barriers.
Initiation, promotion and complete carcinogenesis by N-methyl-N′-nitro-N-nitrosoguanidine or ethylnitrosourea in the Sencar mouse skin tumorigenesis model

Abstract Five doses of either N -methyl- N′ -nitro- N -nitrosoguanidine (MNNG) or ethylnitrosourea (ENU) were tested as complete carcinogens, tumor initiators and tumor promoters in the SENCAR skin tumorigenesis model. As tumor initiators, MNNG-induced papillomas at all doses tested, while ENU was active from 10–40 μmol. As complete carcinogens, MNNG from doses of 0.5–5.0 μmol and ENU from doses of 10 μmol–40 μmol were potent inducers of both papillomas and carcinomas indicating that these agents are active as both tumor initiators and tumor promoters.
Demonstration of PDGF B-chain mRNA in glomeruli in mesangial proliferative nephritis by in situ hybridization.

Demonstration of PDGF B-chain mRNA in glomeruli in mesangial proliferative nephritis by in situ hybridization. We used the technique of in situ hybridization to determine if cells expressing PDGF B-chain mRNA can be detected in a model of mesangial proliferative nephritis in the rat induced with antibody directed against the Thy 1 antigen present on the mesangial cell membrane. The method involved hybridization with a digoxigenin-labeled cRNA probe for the murine PDGF B-chain followed by detection with an anti-digoxigenin-alkaline phosphatase conjugate and subsequent colorimetric reaction. In normal rats (N = 4), the majority of glomeruli (74%) were negative for PDGF B-chain mRNA, whereas 65% of glomeruli from rats with mesangial proliferative nephritis (N = 4) had segmental or diffuse staining for PDGF B-chain mRNA in a mesangial pattern. The difference, as measured using a semiquantitative scale, was significant (mean scores 0.4 ± 0.2 vs. 1.9 ± 0.2; scale 0 to 3+ ; P
Enhancement of DNA tumor vaccine efficacy by gene gun-mediated codelivery of threshold amounts of plasmid-encoded helper antigen.

Nucleic acid–based vaccines are effective in infectious disease models but have yielded disappointing results in tumor models when tumor-associated self-antigens are used. Incorporation of helper epitopes from foreign antigens into tumor vaccines might enhance the immunogenicity of DNA vaccines without increasing toxicity. However, generation of fusion constructs encoding both tumor and helper antigens may be difficult, and resulting proteins have unpredictable physical and immunologic properties. Furthermore, simultaneous production of equal amounts of highly immunogenic helper and weakly immunogenic tumor antigens in situ could favor development of responses against the helper antigen rather than the antigen of interest. We assessed the ability of 2 helper antigens (β-galactosidase or fragment C of tetanus toxin) encoded by one plasmid to augment responses to a self-antigen (lymphoma-associated T-cell receptor) encoded by a separate plasmid after codelivery into skin by gene gun. This approach allowed adjustment of the relative ratios of helper and tumor antigen plasmids to optimize helper effects. Incorporation of threshold (minimally immunogenic) amounts of helper antigen plasmid into a DNA vaccine regimen dramatically increased T cell–dependent protective immunity initiated by plasmid-encoded tumor-associated T-cell receptor antigen. This simple strategy can easily be incorporated into future vaccine trials in experimental animals and possibly in humans.
Gender and carotid endarterectomy: does it matter?

Abstract Objective: Multiple large series have retrospectively identified female gender as a risk factor for perioperative stroke and death after carotid endarterectomy (CEA). Methods: Data for all patients who underwent CEA at a single institution from January 1990 to December 1998 were entered into a computerized vascular registry and form the basis of this report. Results: A total of 1298 CEA procedures were performed, of which 520 (40%) were in women and 778 (60%) in men. The mean age was 69.8 ± 8.7 years for men and 71.2 ± 8.5 years for women ( P P P =.022). Postoperative myocardial infarction occurred in eight patients (0.6%) with no differences between men (0.4%) and women (1.0%) ( P = not significant). For all adverse postoperative cardiac events (myocardial infarction, congestive heart failure, or arrhythmia), the incidence was 1.9% (25 patients), again with no differences between men (1.5%) and women (2.5%) ( P = not significant). There were 25 postoperative neurologic events (19 strokes, six transient ischemic attacks) among the entire cohort (1.9%), of which 16 were in men (2.1%) and nine in women (1.6%; P = not significant). The overall postoperative stroke rate was 1.5% (13 [1.7%] of 778 men; 6 [1.2%;] of 520 women; P = not significant). Total operative mortality was 0.3% (3 [0.4%] of 778 men; 1 [0.2%] of 778 women; P = not significant). Late recurrent stenosis requiring operation developed in 14 patients (1.1%) during follow-up (6 [0.8%] of 778 men; 8 [1.5%] of 520 women; P =.19). Conclusions: Although there is significant variability in cardiac risk factors and presentation, female gender is not a risk factor for stroke, death, or cardiac morbidity after CEA. Women are not at higher risk for reoperation for recurrent stenosis. (J Vasc Surg 2000;31:1103-9.)
Activities of ornithine aminotransferase and ornithine decarboxylase in chronically uremic rats

Abstract The activities of two enzymes mediating different pathways of ornithine catabolism were measured in liver and kidney of chronically uremic rats and their pair-fed controls. Two months following partial nephrectomy hepatic ornithine aminotransferase (OAT) activity tended to be lower in uremic rats and was correlated with urea clearance and with carbamoyl phosphate synthetase activity. Renal OAT activity in uremic rats was also correlated with urea clearance. When uremic rats were maintained for five months, OAT activity was significantly decreased in liver but not in kidney and the activity of ornithine decarboxylase (ODC), the enzyme regulating polyamine biosynthesis, was reduced in both liver and kidney. In cross-over experiments, evidence was obtained for a factor in uremic kidney cytosol which inhibited renal ODC activity.
Construction of an alkaline phosphatase fusion-generating transposon, mTn10phoA

Abstract We constructed a derivative of the mini-transposon mTn10 that generates translational fusions to the phoA gene from Escherichia coli and carries the Km R determinant from Tn5. This new transposon, mTn 10phoA , is carried on a mobilizable plasmid with both selectable and counterselectable markers. The plasmid carrying mTn 10phoA was introduced into Legionella pneumophila. Southern hybridization analysis indicated that the mTn 10phoA insertions were randomly distributed
Short-Term Loan

We find ourselves expending all our effort in gaining technical skills to make the objects or design the systems that benefit society, with little time to broaden our intellectual basis. The Web extra at http://youtu.be/_3hELfdp0-c is a video segment in which author David Alan Grier expands on his Errant Hashtag column, discussing career arcs in technical fields from design to management to leadership and the value of having an engineering degree.
Differences between methamphetamine users and cocaine users in treatment

To better understand the distinguishing characteristics of methamphetamine users versus cocaine users, we conducted a retrospective chart review of the 345 patients admitted to an outpatient stimulant treatment program during 1995--1997. Analyses revealed an increase in methamphetamine patients over the 3-year period, and that these patients were more likely than cocaine patients to be male, Caucasian, and gay or bisexual. Methamphetamine patients were also more likely to be HIV-positive, engage in behaviors such as using and sharing needles that place them at high risk for HIV transmission, have a psychiatric diagnosis, and be on psychiatric medications. The two populations did not differ in treatment adherence, as measured by clinic attendance, drug-free urines, and successful completion of treatment. These findings suggest that highly specialized substance abuse treatments for methamphetamine patients may not be needed. Resources may be directed toward addressing their medical and psychiatric diagnostic issues by providing ancillary services to stimulant treatment programs.
Quantitative determination of the oxidation state of iron in biotite using x-ray photoelectron spectroscopy: II. In situ analyses

Abstract X-ray photoelectron spectroscopy (XPS) was used to determine Fe(III)/ΣFe in individual biotite crystals in thin sections of ten metapelites and one syenite. The in situ XPS analyses of Fe(III)/∑Fe in biotite crystals in the metapelites were compared with published Fe(III)/IFe values determined by Mossbauer spectroscopy (MS) for mineral separates from the same hand samples. The difference between Fe(HI)/ΣFe by the two techniques was greatest for samples with the lowest Fe(III)/ΣFe (by MS). For eight metamorphic biotites with Fe(III)/ΣFe = 9–27% comparison of the two techniques yielded a linear correlation of r = 0.94 and a statistically acceptable fit of [Fe(III)/ΣFe]xps = [Fe(IIl)/ ΣFe]ms. The difference between Fe(III)/1Fe by the two techniques was greater for two samples with Fe(III)/ΣFe ≤ 6% (by MS). For biotite in the syenite sample, Fe(III)/ΣFe determined by both in situ XPS and bulk wet chemistry/electron probe microanalysis were similar. This contribution demonstrates that XPS can be used to analyze bulk Fe(III)/ΣFe in minerals in thin sections when appropriate precautions are taken to avoid oxidation of the near-surface during preparation of samples.
Niobium nitride: Stability and integrity of the “NbO phase”

Abstract The ordered vacancy Pm3m (“NbO”) structure was identified by Treece et al. as the phase of their pulsed laser deposited thin film samples of niobium nitride. However, the stoichiometric Pm3m phase of NbN is not easily reconciled with published local density functional results, which predict a 5% smaller lattice constant than measured and a high energy compared with the competing rocksalt phase (which is common and therefore expected to be the stable phase). Here we investigate a possible tetragonal instability of the Pm3m structure that might complicate the interpretation of xray data on the thin films. We also consider the consequences of incorporation of hydrogen into the films. Neither of these aspects is able to resolve the apparent discrepancy.
Atomic Physics Of Shocked Plasma In Winds Of Massive Stars

High resolution diffraction grating spectra of X-ray emission from massive stars obtained with Chandra and XMM-Newton have revolutionized our understanding of their powerful, radiation-driven winds. Emission line shapes and line ratios provide diagnostics on a number of key wind parameters. Modeling of resolved emission line velocity profiles allows us to derive independent constraints on stellar mass-loss rates, leading to downward revisions of a factor of a few from previous measurements. Line ratios in He-like ions strongly constrain the spatial distribution of Xray emitting plasma, confirming the expectations of radiation hydrodynamic simulations that X-ray emission begins moderately close to the stellar surface and extends throughout the wind. Some outstanding questions remain, including the possibility of large optical depths in resonance lines, which is hinted at by differences in line shapes of resonance and intercombination lines from the same ion. Resonance scattering leads to nontrivial radiative transfer effects, and modeling it allows us to place constraints on shock size, density, and velocity structure.
Specificity, stereochemistry, and mechanism of the color reaction between p-dimethylaminocinnamalhyde and biotin analogs.

Abstract Biotin and other cyclic ureido compounds monoalkylated on each nitrogen have been shown to react with p-dimethylaminocinamaldehyde in anhydrous solution or on dry chromatograms in a classic way for formation of the conjugate imine. The reaction is quite stereospecific and, though occurring at either nitrogen in simple 2-imidazolidones without bulky substituents, proceeds only at that nitrogen (N1) in biotin and closely related analogs that is farthest from the side chain. The d-sulfoxides and sulfones of biotin and analogs produce less color, because the oxygen on the exo-side of the sulfur prevents the necessary conformation of the product imine. Over-all, the color reaction is very useful for quantitating and even identifying microgram amounts of the vitamin and many related forms, both natural and synthetic, and is not interfered with by usual biochemicals.
Microcalorimetric measurement of aerobic cell metabolism in unstirred cell cultures

Abstract Studies of cell metabolism in small-volume, unstirred calorimeters has been limited by the problem of oxygen diffusion to the cells. Many cell types settle to the bottom of the sample container and become essentially anaerobic. Cells subjected to these conditions generally die, or when capable, alter metabolism to anaerobic pathways. Metabolic heat measurements in such conditions do not reflect normal metabolism and provide little information about normal metabolic rates. To avert this problem, the densities of the media supporting growth of animal and plant cells were increased by addition of sterile solutions of Percoll, causing cells to float at the surface of the media where they could readily absorb oxygen. Under these conditions, a wide range of cell types were studied. Plant, microbial, and animal cells could be analyzed for responses to metabolic effectors or environmental factors which influence growth.