cssi/SciSciGPT-SciSciNet huggingface dataset:
Global value chains and international development policy: Bringing firms, networks and policy-engaged scholarship back in

This article argues that the global value chains (GVC) perspective bridges the firm-specific, private-sector and country-level, societal divide that has separated the international business and international economics literatures. A key mechanism that explains the policy impact of the GVC approach are the networks created between the policy entrepreneurs inside the international organizations (IOs) dealing with economic development and the idea entrepreneurs in the research community. The policy engagement of various segments of the GVC research community with development-oriented IOs has increased the scope and visibility of the GVC literature, and improved the quality and relevance of the findings from selected GVC research programs. However, one of the drawbacks of this collaboration has been the multiple meanings attached to the GVC concept and its policy usages within the IOs and national policy communities. The GVC framework remains centrally involved in contemporary research frontiers, including the impact of tariffs on national competitiveness and innovation systems, the digital economy, the future of manufacturing, the co-evolution between local economic clusters and global production networks, and the role of foreign direct investment in establishing complete value chains as a catch-up strategy in developing economies.
CCL21/CCR7 signaling in macrophages promotes joint inflammation and Th17-mediated osteoclast formation in rheumatoid arthritis.

In rheumatoid arthritis (RA), synovial tissue abundantly expresses CCL21, a chemokine strongly associated with RA susceptibility. In this study, we aimed to characterize the functional significance of CCL21/CCR7 signaling in different phases of RA pathogenesis. We determined that CCR7 is a hallmark of RA M1 synovial fluid (SF) macrophages, and its expression in RA monocytes and in vitro differentiated macrophages is closely associated with disease activity score (DAS28). In early stages of RA, monocytes infiltrate the synovial tissue. However, blockade of SF CCL21 or CCR7 prevents RA SF-mediated monocyte migration. CCR7 expression in the newly migrated macrophages can be accentuated by LPS and IFNγ and suppressed by IL-4 treatment. We also uncovered that CCL21 stimulation increases the number of M1-polarized macrophages (CD14+CD86+), resulting in elevated transcription of IL-6 and IL-23. These CCL21-induced M1 cytokines differentiate naive T cells to Th17 cells, without affecting Th1 cell polarization. In the erosive stages of disease, CCL21 potentiates RA osteoclastogenesis through M1-driven Th17 polarization. Disruption of this intricate crosstalk, by blocking IL-6, IL-23, or IL-17 function, impairs the osteoclastogenic capacity of CCL21. Consistent with our in vitro findings, we establish that arthritis mediated by CCL21 expands the joint inflammation to bone erosion by connecting the differentiation of M1 macrophages with Th17 cells. Disease progression is further exacerbated by CCL21-induced neovascularization. We conclude that CCL21 is an attractive novel target for RA therapy, as blockade of its function may abrogate erosive arthritis modulated by M1 macrophages and Th17 cell crosstalk.
Making Geometry a Personal and Inventive Experience.

A major goal of mathematics teaching is the involvement of our students in the personal process of discovering mathe matical ideas and formulating problems. Students who use educated guesses to solve a problem or to judge whether an other student's hunch is correct are com mitting themselves to an exhilarating process. This process of an inductive leap followed by a deductive argument has been used during the centuries in the growth of mathematics. Geometry is a perfect subject for the application of these principles. It is quick ly apparent to students beginning a geom etry course that the subject is much differ ent from previous mathematics courses. There are no elaborate arithmetic prob lems, no polynomials to factor, and few equations to solve. And most different of all is geometric proof, where the solution is not a neat number or algebraic expres sion that can be underlined and labeled "answer." It takes time for students to adjust to these differences, but there is another reason why proof is difficult for many. To illustrate, consider a standard original proof (table 1). Here the student must invent a chain of deductions to ar
Epigenetic predictors of all-cause mortality are associated with objective measures of neighborhood disadvantage in an urban population

Neighborhood characteristics are robust predictors of overall health and mortality risk for residents. Though there has been some investigation of the role that molecular indicators may play in mediating neighborhood exposures, there has been little effort to incorporate newly developed epigenetic biomarkers into our understanding of neighborhood characteristics and health outcomes. Using 157 participants of the Detroit Neighborhood Health Study with detailed assessments of neighborhood characteristics and genome-wide DNA methylation profiling via the Illumina 450K methylation array, we assessed the relationship between objective neighborhood characteristics and a validated DNA methylation-based epigenetic mortality risk score (eMRS). Associations were adjusted for age, race, sex, ever smoking, ever alcohol usage, education, years spent in neighborhood, and employment. A secondary model additionally adjusted for personal neighborhood perception. We summarized 19 neighborhood quality indicators assessed for participants into 9 principal components which explained over 90% of the variance in the data and served as metrics of objective neighborhood quality exposures. Of the nine principal components utilized for this study, one was strongly associated with the eMRS (β = 0.15; 95% confidence interval = 0.06–0.24; P = 0.002). This principal component (PC7) was most strongly driven by the presence of abandoned cars, poor streets, and non-art graffiti. Models including both PC7 and individual indicators of neighborhood perception indicated that only PC7 and not neighborhood perception impacted the eMRS. When stratified on neighborhood indicators of greenspace, we observed a potentially protective effect of large mature trees as this feature substantially attenuated the observed association. Objective measures of neighborhood disadvantage are significantly associated with an epigenetic predictor of mortality risk, presenting a potential novel avenue by which neighborhood-level exposures may impact health. Associations were independent of an individual’s perception of their neighborhood and attenuated by neighborhood greenspace features. More work should be done to determine molecular risk factors associated with neighborhoods, and potentially protective neighborhood features against adverse molecular effects.
Skin cancer risk in CHEK2 mutation carriers

CHEK2 mutations have been linked with an increased risk of breast cancer. A unique challenge for oncodermatologists and oncologists is in the monitoring and counselling of patients regarding skin cancer risk due to CHEK2 mutation carrier status. In this review, we highlight current information in the literature on the risk of melanoma and non-melanoma skin cancers in CHEK2 mutation carriers. On the molecular level, CHEK2 is a cell cycle regulator that has been linked to cancer pathogenesis, though evidence from clinical studies regarding skin cancer risk has been inconsistent and conflicting. For melanoma, one study has demonstrated a statistically significant twofold risk of melanoma in individuals with CHEK2 mutations, particularly the CHEK2*1100delC variant. Five other studies did not show an association. For non-melanoma skin cancer, fewer data exist, with one prevalence study of CHEK2 mutations in a cohort of patients with basal cell carcinomas. Although there are currently no known studies of CHEK2 and cutaneous squamous cell carcinoma (SCC), data from other disciplines associating CHEK2 with head and neck SCCs are emerging. Overall, while there is currently not enough evidence to make conclusive statements regarding increased risk of melanoma and non-melanoma skin cancers in CHEK2 carriers, a molecular mechanism associating the mutation with cutaneous malignancy pathogenesis is evident, and further work is needed. Patient with CHEK2 mutations may benefit from screening dermatologic examinations with particular attention to skin cancers.
Genetic Analysis in Kidney Disease: Advancing Clinical Diagnosis and Research Discovery

Nephrologists are increasingly including genetic diagnosis into clinical practice as sequencing costs come down, availability improves, and the list of kidney disease genes becomes more complete. Multiple studies suggest that around 10% of the adult ESKD population and 30% of pediatric cohorts have an identifiable genetic kidney disease (1⇓–3). One study found that genetic diagnosis provided new clinical insight in nearly 75% of solved cases by identifying, reclassifying, or specifying disease etiology or informing prognostication, treatment, or transplant decisions (1). Many nephrologists have little experience with genetic testing, and thus, they may have uncertainty about whom to test, what test to select, and what to expect from the genetic results. Kidney disease phenotypes can be caused by mutations in any of hundreds of genes. The exons, which are protein-encoding regions of genes that make up only 1% of the whole genome known as the “exome,” are estimated to carry at least 85% of disease-causing variants (4). Next generation sequencing (NGS), also known as massively parallel sequencing, can evaluate all >18,000 genes or a targeted list of genes. NGS can be done on the whole genome, whole exome, or a selection of genes within the exome; these are known as whole-genome sequencing (WGS), whole-exome sequencing (WES), or targeted NGS, respectively (Figure 1A). Because of their efficient multiplexing, these methods provide a clear advantage over Sanger sequencing individual PCR amplicons for all but a small number of indications. Sequencing of individual variants, such as a known familial variant or specific risk allele, or a short list of genes specified by the phenotype does not require NGS, but the list of genes to evaluate does not need to be long before NGS becomes more cost effective. Large deletions or duplications also known as copy number variations are not detected by …
Spatial Configurations of Land Cover Influence Flood Regulation Ecosystem Services

AbstractUrbanization is one of the most aggressive forms of land transformation, leading to negative impacts on surrounding aquatic and terrestrial ecosystems. In terms of hydrology, urbanization c...
The Impact of Merit Aid on College Choice and Degree Attainment: Reexamining Florida’s Bright Futures Program

We replicate and extend prior work on Florida’s Bright Futures merit aid scholarship to consider its effect on college enrollment and degree completion. We estimate causal impacts using a regressio...
Wissenschaft schätzen lernen

Wenn das Konzept, das ich in den vorhergehenden Kapiteln erarbeitet habe, stimmig ist, sind wir damit in der Lage, den Erfolg der Wissenschaft 1) zu erklaren, 2) ihn zu verteidigen, wo er bereits erkennbar ist, und 3) ihn auf andere Bereiche zu ubertragen. Wenn Fachgebiete wie die Sozialwissenschaften mehr wissenschaftliche Sorgfalt anstreben, mussen sie dabei den Weg gehen, den auch andere Gebiete wie die Medizin beschritten haben: Sie mussen eine wissenschaftliche Grundhaltung umsetzen.
Arthroscopic Diagnosis of Occult Posterolateral Meniscocapsular Separations: Another Hidden Lesion.

Purpose The purpose of this study was to describe the surgical findings and clinical outcomes in a series of patients with occult posterolateral meniscocapsular separations diagnosed arthroscopically after a negative magnetic resonance imaging (MRI) scan. Methods A retrospective analysis of prospectively collected data of consecutive patients who underwent surgical arthroscopy with repair of an occult posterolateral meniscocapsular separation by 2 fellowship-trained orthopaedic sports medicine surgeons at a single institution was performed. All lesions were identified arthroscopically in the posterolateral aspect of the lateral compartment as a distinct pathologic separation between the posterolateral capsule and adjacent meniscal tissue with increased excursion on probing. Clinical examination notes, MRI scans, and operative reports were reviewed. Patient-reported outcome measures were assessed via patient questionnaire. Results A total of 6 patients were included for analysis. MRI evaluation of the lateral meniscus was unrevealing in 4 patients, suggesting a possible tear of the body of the lateral meniscus in one patient and demonstrating a parameniscal cyst abutting the anterior root of the lateral meniscus in another patient. Arthroscopic examination revealed meniscocapsular separations of the posterolateral meniscus in all 6 knees, with 2 knees demonstrating concomitant bucket-handle meniscus tears. Patient-reported outcomes were determined for 67% of study patients. The average reported International Knee Documentation Committee score was 63.8, the average Knee Outcome Survey Activities of Daily Living Scale score was reported as 63, the 12-Item Short Form Survey (SF-12) Physical score averaged 46.8 with an average SF-12 Mental score of 59.9. Conclusions The diagnosis of occult posterolateral meniscocapsular separations (MCS) could be missed on advanced imaging, such as MRI, so arthroscopic diagnosis may be required. This study indicates that arthroscopic diagnosis and repair of occult posterolateral MCS results in good functional and clinical outcomes. Level of Evidence IV, therapeutic case series.
Mechanical Shock Environment Synthesis for Structural Failure Elicitation

Shock Response Spectra (SRS) are commonly used in dynamic testing to describe the mechanical environment in high-energy, non-stationary events, such as impacts or pyrotechnic shocks. Oftentimes, the service environment to which a structure will be exposed is difficult to reproduce in the laboratory, but design engineers desire a laboratory screening test to determine whether the structure will survive an anticipated shock environment. Herein, a combined experimental and numerical study is pursued to evaluate the efficacy of different methods to elicit failure modes of a service shock through destructive shaker tests of a custom-designed test article fabricated using commercially available 3-D printers. Design of the test article is explored through use of finite element modeling, which is found to correlate well to experimentally-obtained natural frequencies. Four techniques to synthesize a service shock are compared: least favorable response, sum of decaying sinusoids, wavelet, and matching temporal moments. Destructive shaker tests of the shock responses are performed using 25 nominally identical test articles to assess the ability of each method to impose similar damage states as those obtained when using the service shock. We find that the method of matching temporal moments best replicates failure modes of the service shock; however, further testing is needed to validate our observations.
Some thoughts on the role of robust control theory in climate-related decision support

Climate change is sure to surprise us, both in its impacts and in the technological and behavioral changes that will affect society’s ability to respond (NRC 2009). Any successful response to climate change—both the challenges of limiting the magnitude of future climate change and adapting to its impacts—will clearly involve policies that evolve over time in response to new information and that are robust over a wide range of difficult-to-predict future conditions. Recent years have seen expanding interest in decision frameworks and approaches to help identify and evaluate such policies. Funke and Paetz (2011) offer robust control theory as one means to evaluate such robust and adaptive policies for reducing greenhouse gas emissions.
Vapor-liquid equilibrium behavior of the ethane—n-butane—n-hexane system

A high pressure visual cell was designed and constructed for the study of vapor-liquid equilibria of rnulticomponmt systems at elevated temperatures and pressures. One of the unique features of this vapor-liquid equilibrium cell facility resides in the ability to measule pressures using a transducer connectcd directly to the equilibrium chamber of this cell. In addition, the design of this cell, incorporated the capability to permit the withdrawal of vapor and liquid microsamples from the respective phases in equilibrium. The composition of these microsamples was established with a gas chromatographic facility provided with a thermal conductivity detector. The overall performance of this vapor-liquid equilibriiini facility was tested on the system ethane-n-butane for which reliable vapor-liquid equilibrium data are already available in the literature. Five different charges of the ethane-n-butane-n-hexane system were investigated with this facility for temperatures ranging from 48.3 up to 143.5°C and pressures up to 7619 kPa (75.19 atm). For these conditions, K-values were established from the experimental measurements on this ternary system. K-values calculated using the BWR-method for conditions corresponding to the experimental measurements produced K-constants that were in good agreement with the measured values. For these calculations, the original BWR-equation, constants and mixing rules were employed.
The Alphavirus E3 Glycoprotein Functions in a Clade-Specific Manner

ABSTRACT The 80 trimeric, glycoprotein spikes that cover the surface of alphavirus particles are required for mediating viral entry into a host cell. Spike assembly is a regulated process that requires interactions between five structural proteins, E3, E2, 6K and its translational frameshift product TF, and E1. E3 is a small, ∼65-amino-acid glycoprotein that has two known functions: E3 serves as the signal sequence for translocation of the E3-E2-6K-E1 polyprotein into the endoplasmic reticulum (ER), and cleavage of E3 from E2 is essential for virus maturation. Nonetheless, when E3 is replaced with an ER signal sequence, spikes do not form and infectious particles are not assembled, suggesting an additional role(s) for E3 in the viral life cycle. To further investigate the role of E3 in spike assembly, we made chimeric viruses in which E3 from one alphavirus species is replaced with E3 from another species. Our results demonstrate that when E3 is interchanged between alphavirus species that belong to the same virus clade, viral titers and particle morphologies and compositions are similar to what are observed for the parental virus. In contrast, for chimeras in which E3 is derived from a different clade than the parental virus, we observed reduced titers and the formation of particles with atypical morphologies and protein compositions. We further characterized the E3 chimeras using a combination of structure-function and revertant analyses. This work revealed two specific interactions between E3 and its cognate E2 glycoprotein that are important for regulating spike assembly.
Diagnostic and Value-Added Assessment of Business Writing.

To assess students’ business writing abilities upon entry into the business program and exit from the capstone course, a multitiered assessment package was developed that measures students’ achieve...
Management of infected arterial grafts.

Summary Infection involving an arterial graft remains a challenging complication of vascular surgery. The mortality and morbidity remain exceedingly high. Five of our cases have prompted a re-evaluation of our management and a review of the literature. It is apparent there are many ideas about the fate of grafts in the presence of infection. It has become clear to us that: (1) not all prosthetic grafts placed in a contaminated area are destined to failure; (2) sepsis does affect a nonthrombosed arterial graft occasionally; (3) exposed segments of graft that are not near suture lines heal when covered with healthy tissue; (4) vein grafts are not capable of healing and functioning in the presence of sepsis. Infection around arterial grafts must be considered hospital-acquired. Therefore, strict attention must be paid to the prevention of this complication. Pre-, intra-, and postoperative preventive measures are presented. Particular attention should be given to the use of preoperative antibiotics, including bowel preparation. Inguinal incisions should be avoided whenever possible. There are many ways that this complication may be managed, depending on the site and extent of the infection. A guideline to principles of management is proposed.
Transport and biodegradation of perchlorate in soils.

Perchlorate (ClO - 4 ) contamination of ground water and surface water is a widespread problem, particularly in the western United States. This study examined the effect of biodegradation on perchlorate fate and transport in soils. Solute transport experiments were conducted on two surface soils. Pulses of solution containing perchlorate and Br - were applied to saturated soil columns at steady state water flow. Perchlorate behaved like a nonreactive tracer in Columbia loam (coarse-loamy, mixed, superactive, nonacid, thermic Oxyaquic Xerofluvent) but was degraded in Yolo loam (fine-silty, mixed, super-active, nonacid, thermic Mollic Xerofluvent). Batch experiments demonstrated that perchlorate removal from solution in Yolo loam was caused by biodegradation. Other batch experiments with Yolo loam surface and subsurface soils, Columbia loam surface soil, and dredge tailings demonstrated that perchlorate biodegradation required anaerobic conditions, an adequate carbon source, and an active perchlorate-degrading microbial population. The sequential reduction of perchlorate and NO - 3 by an indigenous soil microbial community in Yolo loam batch systems was also studied. Nitrate reduction occurred much sooner than perchlorate reduction in soils that had not been previously exposed to perchlorate, but NO - 3 and perchlorate were simultaneously reduced in soils previously exposed to perchlorate. The results of this study have implications for in situ remediation schemes and for agricultural soils that have been contaminated by perchlorate-tainted irrigation water.
Ovarian suppression with a gonadotropin-releasing hormone agonist does not alter insulin-stimulated glucose disposal.

Objective Aging is associated with reduced tissue sensitivity to insulin. In women, these age-related changes may be accelerated by menopause. The effect of ovarian hormone deficiency on tissue insulin sensitivity in humans, however, has not been defined clearly. Thus, the goal of this study was to evaluate the effect of suppression of endogenous ovarian hormone production on insulin-stimulated glucose disposal. Design Randomized, single-blind, placebo-controlled trial. Setting General clinical research center. Patients Thirteen healthy, nonobese premenopausal women. Intervention(s) Insulin-stimulated glucose disposal was determined by hyperinsulinemic (40 mU/m 2 /min) clamp during the early to midfollicular and midluteal phase of the menstrual cycle. Volunteers then received 2 months of treatment with the GnRH agonist (GnRHa) leuprolide acetate (n = 6) or placebo (n = 7) and were retested. Main Outcome Measure(s) Total, oxidative, and nonoxidative insulin-stimulated glucose disposal. Result(s) Because no effect of cycle phase was found on total, oxidative, or nonoxidative glucose disposal, pretreatment follicular and luteal phase values were averaged. Treatment with GnRHa had no effect on total glucose disposal (GnRHa: 10.6 ± 0.9 to 10.8 ± 0.9 vs. placebo: 10.2 ± 0.7 to 10.4 ± 1.0 mg/kg fat-free mass/min, P = .99). Similarly, there was no effect of GnRHa administration on oxidative (GnRHa: 2.77 ± 0.58 to 3.89 ± 0.58 vs. placebo: 2.74 ± 0.42 to 3.33 ± 0.62 mg/kg fat-free mass/min, P = .52; n=6 and 6, respectively) or nonoxidative (GnRHa: 7.82 ± 0.68 to 6.91 ± 0.66 vs. placebo: 7.94 ± 0.72 to 7.79 ± 0.99 mg/kg fat-free mass/min, P = .59; n=6 and 6, respectively) components of glucose disposal. Conclusion(s) Our results suggest that endogenous ovarian hormones do not regulate tissue responsiveness to insulin or intracellular pathways of glucose disposal.
Conduct disorder and mania: what does it mean in adults

Objective: Because of the relationship between childhood behavior disorders and adult substance abuse, we hypothesized that substance abusing adult bipolars were more likely to have had behavior disorders as children than nonabusing bipolar adults. Methods: Conduct disorder (CD) symptoms in 132 bipolar adults were compared by age and presence of comorbid substance use problems using data from the Epidemiologic Catchment Area study. Results: Rates of CD were higher in bipolar subjects under age 30 (32.6%) versus those over (16.3% P<0.05). Young BPs with substance use problems (SUBST) had CD rates three times those without SUBST (52% vs. 14.8%) (P<0.01). Young subjects without mania or SUBST had CD rates of 7.75%. Conclusion: Substance abuse in bipolar adults may be more related to childhood conduct disorder than uncomplicated bipolar disorder.
Temporal depression of the soleus H-reflex during passive stretch

Synaptic efficacy associated with muscle spindle feedback is regulated via depression at the Ia-motoneurone synapse. The inhibitory effects of repetitive Ia afferent discharge on target motoneurones of different sizes were investigated during a passive stretch of ankle extensors in humans. H-reflex recruitment curves were collected from the soleus muscle for two conditions in ten subjects. H-reflexes were elicited during passive stretch at latencies of 50, 100, 300, and 500 ms after a slow (20°/s) dorsiflexion about the right ankle (from 100 to 90°). Control H-reflexes were recorded at corresponding static (without movement) ankle angles of 99, 98, 94, and 90° of flexion. The slope of the H-reflex recruitment curves (Hslp) was then calculated for both conditions. H-reflex values were similar for the static and passive stretch conditions prior to 50–100 ms, not showing the early facilitation typical of increased muscle spindle discharge rates. However, the H-reflex was significantly depressed by 300 ms and persisted through 500 ms. Furthermore, less than 300 ms into the stretch, there was significantly greater H-reflex depression with a lower stimulus intensity (20 % Mmax) versus a higher stimulus intensity (Hmax), though the effects begin to converge at later latencies (>300 ms). This suggests there is a distinct two-stage temporal process in the depression observed in the Ia afferent pathway for all motoneurones during a passive stretch. Additionally, there is not a single mechanism responsible for the depression, but rather both heterosynaptic presynaptic inhibition and homosynaptic post-activation depression are independently influencing the Ia-motoneurone pathway temporally during movement.
Purinergic P2X7 Receptors Mediate ATP-induced Saliva Secretion by the Mouse Submandibular Gland

Salivary glands express multiple isoforms of P2X and P2Y nucleotide receptors, but their in vivo physiological roles are unclear. P2 receptor agonists induced salivation in an ex vivo submandibular gland preparation. The nucleotide selectivity sequence of the secretion response was BzATP ≫ ATP > ADP ≫ UTP, and removal of external Ca2+ dramatically suppressed the initial ATP-induced fluid secretion (∼85%). Together, these results suggested that P2X receptors are the major purinergic receptor subfamily involved in the fluid secretion process. Mice with targeted disruption of the P2X7 gene were used to evaluate the role of the P2X7 receptor in nucleotide-evoked fluid secretion. P2X7 receptor protein and BzATP-activated inward cation currents were absent, and importantly, purinergic receptor agonist-stimulated salivation was suppressed by more than 70% in submandibular glands from P2X7-null mice. Consistent with these observations, the ATP-induced increases in [Ca2+]i were nearly abolished in P2X7–/– submandibular acinar and duct cells. ATP appeared to also act through the P2X7 receptor to inhibit muscarinic-induced fluid secretion. These results demonstrate that the ATP-sensitive P2X7 receptor regulates fluid secretion in the mouse submandibular gland.
Stimulated amplification of a broad-band optical signal through a benzene-core fiber system pumped by ultra-short laser pulses

Abstract This paper presents a novel approach to amplify a broad-band optical signal by using stimulated Rayleigh-Kerr scattering in a hollow core fiber system filled with liquid benzene. Using 4 ps dye laser pulses as the pump source, stimulated amplification of the accompanying ≈ 550 cm-1 broad spontaneous emission is achieved with an amplification factor reaching 2.3 × 104.
The potential dependence of reaction product composition on copper-nickel alloys

Abstract The potential dependence of reaction product composition has been studied on high purity binary Cu-Ni alloys (10–40%Ni) in 0·5M sodium chloride solution at 25°C. The results show that the reaction products contain Ni concentrations in excess of those in the alloys at 0·00 V and below. The composition of solid reaction product films is more potential dependent than that of the overall reaction products. Controlling mechanisms are discussed.
Theoretical studies on extended solid solubility and nonequilibrium phase diagram for Nb-Al alloy formed during laser cladding

A model for extended solid solution during laser cladding was recently presented and the predicted values for the nonequilibrium compositions of Ni-Hf and Ni-Al systems were shown to be in good agreement with the experimental results. The model is used in this study to construct a non-equilibrium phase diagram for Nb-Al system. The model is also used to study the effect of various process parameters on the composition of solid solution in the laser clad of Nb-Al binary alloys. The results compare well with experimental data.
Thymocyte selection: chemokine signaling is not only about the destination.

Summary The development and function of lymphocytes depend upon their precise migration in response to chemoattractant cytokines, or chemokines. Two recent reports suggest that, during thymic β-selection, the binding of the chemokine CXCL12 to the receptor CXCR4 on thymocytes provides not only directional but also developmental cues.
Effect of intermittent hypoxia on long-term potentiation in rat hippocampal slices

Intermittent hypoxia (IH) during sleep has been shown to induce apoptosis in a time-dependent manner and spatial learning deficits in adult rats. Recently, we have demonstrated that IH induced significant decreases in Ser-133-phosphorylated cAMP-response element-binding protein (pCREB) without changes in total CREB. The expression of cleaved caspase 3 in the hippocampal CA1, a marker of apoptosis, peaked at 3 days of IH and returned to normoxic values at 14 days of IH. In addition, biphasic changes in spatial task learning were correlated with the CREB phosphorylation time course. In the present study, the rat hippocampal slice preparation was used to evaluate the ability to induce and maintain a CA1 population spike long-term potentiation (PS-LTP) in room air (RA)-maintained and IH-exposed rats. A significant decrease in the ability to sustain PS-LTP for 15 min in slices prepared from IH-exposed rats for either 3 days (34% of total) or 7 days (51% of total) as compared to slices prepared from RA-maintained rats (76% of total) was observed. These results suggest that the diminishment in the ability of neuronal tissue to express and sustain PS-LTP is correlated with previously reported biphasic changes in CREB phosphorylation and programmed cell death.
Chicken MHC class I and II gene effects on antibody response kinetics in adult chickens

The major histocompatibility complex (MHC) plays an important role in regulation of the immune response. The MHC class I and II genes were selected as candidates to investigate associations with vaccine response to Salmonella enteritidis and kinetics of antibody response to sheep red blood cell (SRBC) and Brucella abortus. Primary antibody response after S. enteritidis vaccination at day 10, and antibody response to SRBC and killed B. abortus after immunization at 19 and 22 weeks were measured in an F2 population. The resource population was derived from males of two highly inbred MHC-congenic Fayoumi chicken lines (M5.1 and M15.2) mated with highly inbred G-B1 Leghorn line hens. Secondary phase parameters of minimum titers ( Y(min)), maximum titers ( Y(max)), and time needed to achieve Y(min) ( t(min)) and Y(max) ( t(max)) were estimated from post-secondary titers by using a non-linear regression model. Associations of single nucleotide polymorphisms (SNPs) in MHC class I and II genes with antibody response parameters were determined by a general linear model. Significant associations were found primarily in the M15.2 grandsire haplotype. There were significant associations between MHC class I alpha(1) and alpha(2) SNPs and antibody response to S. enteritidis, primary antibody response to B. abortus, Y(min) to SRBC, and Y(max) to both SRBC and B. abortus. There were significant effects of the MHC class II beta(1) domain SNP on S. enteritidis antibody and Y(max) to SRBC. The results suggest that the characterized SNPs might be used in future applications by marker-assisted selection to improve vaccine response and immunocompetence in chickens.
Pharmacologic characterization of nicotine-induced conditioned place preference.

Abstract Rats received subcutaneous injections of either nicotine (0.1 to 1.2 mg/kg) or saline (1.0 ml/kg) immediately prior to conditioning sessions in a conditioned place preference (CPP) paradigm. The drug was paired for 3 conditioning sessions with the non-preferred environment of a 3 compartment place preference apparatus; saline was paired with the preferred environment. The animals were then tested for place preference by determining the proportion of time spent in the preferred compartments during a 15 min test session. Using a statistical method developed for the CPP paradigm, dose-response curves were obtained for the obtained from the control animals. Nicotine's rewarding and aversive effects were linearly correlated with respect to dosage within the range of 0.1–0.8 mg/kg (reward increased and aversion decreased). A decrease in reward and an increase in aversion was measured at the 1.2 mg/kg treatment level. Mecamylamine hydrochloride and hexamethonium bromide (at 1.0 mg/kg of the base or ion, respectively) were also tested using the CPP paradigm. While neither compound produced place preferences when administered alone, mecamylamine did block the rewarding effects of 0.8 mg/kg of nicotine when administered 30 minutes prior to the nicotine conditioning sessions. Hexamethonium did not alter nicotine-induced reinforcement. The data suggest that nicotine and its rewarding effects as measured by CPP are primarily mediated by central rather than peripheral events.
A Comparison of Measurement Standard Methods for the Sound Insulation of Building Façades

This paper focuses on the limits of measurement of the sound insulation of building facades at low frequencies. Three standard methods are compared mainly for the position of the equipment. In particular, the positions proposed by the international standard ISO 140-5 and the national standards ASTM E 966 (USA) and JIS A 1430 (Japan) are considered. The limits of measurement of the sound pressure level in front of the facade are investigated. Different placements of the external source and receiver are considered. Moreover, different placements of the receiver inside small rooms are compared by focusing on corner vs. center room positions. The uncertainties of room averaged sound pressure levels measured according to different standards are discussed. The problems of measurement of the reverberation time in small rooms and of sound insulation in irregular shaped rooms are introduced because these measurements present several critical challenges. Finally, suggestions to improve the future version of the ISO...
General strategy for biosensor design and construction employing multifunctional surface-tethered components.

Biosensors function by reversibly linking bioreceptor−target analyte binding with closely integrated signal generation and can either continuously monitor analyte concentrations or be returned to baseline readout values by removal of analyte. We present an approach for producing fully reversible, reagentless, self-assembling biosensors on surfaces. In the prototype biosensor, quencher−dye-labeled biotin-linked E. coli maltose binding protein (MBP) bound in a specific orientation to a NeutrAvidin-coated surface is employed as a bioreceptor. To complete sensor formation, a modular tether arm consisting of a flexible biotinylated DNA oligonucleotide, a fluorescence resonance energy-transfer (FRET) donor dye, and a distal β-cyclodextrin (β-CD) analyte analogue is bound in an equimolar amount to the same surface by means of DNA-directed immobilization. After self-assembly, a baseline level of FRET quenching is observed due to specific interaction between the β-CD of the flexible tether arm and the sugar bindin...
Monitoring ceramic hydroxyapatite media degradation using dynamic image analysis and uniaxial confined bulk compression

Ceramic hydroxyapatite (CHT) is a multimodal chromatographic medium widely used in the pharmaceutical industry for the purification of biomolecules. CHT is a sintered form of hydroxyapatite crystals with moderate stability at acidic conditions. This moderate stability may lead to underperformance of CHT packed bed lifetime, especially under acidic conditions, which should be monitored by diagnostic tools to design optimal buffer systems for the step. This study presents the application of dynamic image analysis (DIA) and uniaxial confined bulk compression (UCBC) to monitor CHT particle degradation as a function of buffer composition. DIA was used to evaluate changes in solidity and morphology, while UCBC was used to evaluate changes in resistance to uniaxial compression. All properties were studied as a function of bed position and operational parameters. Results show that when CHT is exposed to acidic pH, adding phosphate and/or calcium at concentrations of 1 mM minimizes changes in particle solidity and mechanical strength. Changes in CHT morphological properties (i.e., convexity, aspect ratio) are also affected by the presence of calcium and/or phosphate in the inlet buffers. Furthermore, calcium and phosphate have a positive effect on the mechanical behavior of CHT, which is related to changes in the CHT particle solidity.
Sensory Odor Evaluation of Trap Grease and Trap Grease Biodiesel

Waste oils and greases from commercial restaurants, also known as trap grease, are potential feedstocks for sustainable biodiesel production. A significant challenge in producing biodiesel from trap grease is the very strong and offensive odor it can possess. The odor can be attributed to several factors including the volatile chemical compounds created during fermentation and biodegradation of oils and fats. Sensory assessment evaluations were performed on several samples of trap grease, trap grease biodiesel, and reference materials to illustrate different aspects of their odor profile and to gain a better understanding of the odor sources so odor mitigation strategies can be developed and evaluated. Short-chain free fatty acids have been identified as a significant component in trap grease and the odor descriptors commonly associated with short-chain free fatty acids were identified in the trap grease samples evaluated. Biodiesel was prepared from trap grease and found to have a similar odor profile as petrodiesel and other commercially available biodiesels blends. The results from this study show that the odor from trap grease can be mitigated during pretreatment and biodiesel conversion steps and does not represent a significant obstacle to commercialization.
Diabetes and vascular disease: Common links in the emerging epidemic of coronary artery disease

Although diabetes mellitus (DM) is primarily a metabolic disorder, it is also a vascular disease. Most patients with diabetes die from cardiovascular disease (CVD). Several lines of available evidence suggest that cardiovascular complications account for most of the morbidity and mortality associated with diabetes. 1–5 Recent data suggest that diabetes at a younger age (45 years) is associated with increased risk of CVD, and the presence of DM takes away the natural protection from coronary heart disease (CHD) in premenopausal women. 2–3 Perhaps the best evidence regarding the impact of DM on CVD is illustrated by data from a recent prospective study that demonstrated that the risk of developing a myocardial infarction in diabetic patients with no prior history of CHD was equivalent to the risk observed in nondiabetic survivors with a prior myocardial infarction who participated in the same study and were followed for a similar duration of 7 years. 5 These data suggest that diabetic patients may already have developed vascular disease by the time a clinical diagnosis of DM is made. Ravikumar et al’s Chennai Urban Population Study (CUPS) provides strong evidence in support of this concept. 6 THE CHENNAI URBAN POPULATION STUDY (CUPS) The results of CUPS 6 evaluated atherosclerotic markers by noninvasive means and showed evidence of vascular disease by revealing endothelial dysfunction and increased carotid intima-media thickness in diabetic patients with no history of coronary artery disease. 6 The investigators utilized standard methods for the evaluation of endothelial function and carotid intima-media thickness. They carefully selected their patients with diabetes, who were not only free of CHD but who also did not have a history of hypertension or smoking. The clinical characteristics of the nondiabetic control subjects enrolled in the study were well matched with those of the diabetic patients. 6
Black/white differences in the relationship of maternal age to birthweight : a population-based test of the weathering hypothesis

This study seeks to explore if early health deterioration ('weathering') among young adult African American women contributes to observed increases with maternal age in the black/white disparity in birth outcome. Theoretically, 'weathering' is constructed as being a physical consequence of social inequality. Thus, we also examine whether African American mothers vary in their age trajectories of poor birth outcome with respect to social class. Black or white singleton first births to Michigan residents aged 15-34 in 1989 (N = 54,888 births) are analyzed, using data drawn from linked birth and infant death certificates augmented with census-based economic information. We find among blacks, but not whites, advancing maternal age above 15 years is associated with increased odds of LBW and VLBW. Among blacks in low-income areas, the odds of LBW increase 3-fold, and of VLBW 4-fold, between maternal ages 15 and 34. The findings suggest that African American women, on average, and those residing in low-income areas, in particular, experience worsening health profiles between their teens and young adulthood, contributing to their increasing risk of LBW or VLBW with advancing maternal age and to the black-white gap in this risk. The findings suggest the importance of comprehensive prevention strategies to improve the health of socioeconomically disadvantaged African American women prior to pregnancy and the reduction of social inequalities that impact health.
Artifacts associated with the measurement of particulate mercury in an urban environment: The influence of elevated ozone concentrations

Abstract The potential for ozone to cause an artifact during sampling of fine particulate mercury was investigated in southwest Detroit in July 2001 and July 2002. During the July 2001 sampling period, the use of KI and KCl denuders placed upstream to remove ozone and reactive gaseous mercury, Hg 2+ (g) , resulted in more particulate mercury (maximum 33 pg m −3 ) on a denuded filter when compared to an undenuded one. Additionally, a KCl denuded quartz filter also showed more particulate mercury (maximum 12 pg m −3 ) compared to an undenuded filter when ozone concentrations were most elevated. Further sampling in July 2002 used a repeated sampling design and resulted in more particulate mercury on undenuded filters when compared to denuded ones. Conditions in July 2001 were characterized by elevated concentrations of ozone during which there were three ozone action days declared by the State of Michigan whereas ozone concentrations in July 2002 were 22% lower. One possible explanation for the observations may be that elemental mercury, Hg 0 (g) , is oxidized to reactive gaseous mercury, Hg 2+ (g) , during sampling leading to an artifact. The potential for this type of artifact may be greater during periods of high photochemical activity and this must be considered when sampling during the warmer seasons when high levels of oxidants are likely to be present in an urban atmosphere.
Periodic trends in gas phase MH and MC bond energies

Abstract Thermochemistry of simple transition metal species as determined by guided ion beam mass spectrometry is reviewed. Compounds which are discussed include metal hydrides (both ionic and neutral), metal methyls (ionic and neutral), ionic metal methylidenes and metal methylidynes, and bis-methyl metal ions. The periodic trends in this thermochemistry are discussed with an eye on developing ways of applying the data to condensed phase species. The measurement of gas phase BDEs of transition metal species is just emerging from its infancy. The technological and theoretical tools necessary to obtain both accurate and precise values using beam techniques have only recently been developed, as have competing methods (such as photodisso ciation 28 and proton affinity measurements 43,44 ). In combination with values from more established techniques (such as high temperature mass spectrometry 45 and spectroscopy), this gas phase thermochemistry provides a wealth of data which can be analysed for its periodic trends. As outlined above, these analyses can provide intrinsic bond energies for ionic and neutral metal hydrides (57–60 kcal mol −1 ), ionic and neutral metal methyls [2–8 kcal mol −1 higher than D 0 (MH + ) for cationic species, and ∼ 2 kcal mol −1 less than D 0 (MH) for neutral species], ionic metal methylidenes ( ∼ 94 kcal mol −1 ) and ionic metal methylidynes (∼ 130 kcal mol −1 ). Further, the periodic trends can help to identify influential factors in determining the strength or weakness of a bond. These include electronic (essentially hybridization) and polarization effects. Continued studies on even more complex transition metal species should enable even closer relationships between gas and condensed phase thermochemistry to be forged.
On using C++ and object-orientation in CS1: the message is still more important than the medium

Most current approaches to modernizing CS1 revolve around the use of C++ and/or object-orientation. Although the two are not exclusively tied to one another, it is important to pause and consider the potential pitfalls of current approaches. Having identified those pitfalls, this paper presents an approach to CS1 that avoids those pitfalls while focusing students' attention on the real message: software reusability.