cssi/SciSciGPT-SciSciNet huggingface dataset:
The psychology of HPA axis activation: Examining subjective emotional distress and control in a phobic fear exposure model

The HPA axis plays a key role in mediating the effects of "stress" on health, but clarifying mechanisms requires an understanding of psycho-biological linkages. There has long been an implicit assumption that subjective emotional distress (e.g., fear) should activate the HPA axis. Although this assumption was challenged 25 years ago (Curtis, 1976), laboratory studies in humans are limited. In this study we sought to replicate Curtis' findings and extend it by investigating if presence or absence of stressor control shapes HPA axis reactivity in a phobic fear exposure model. We recruited 19-45-year-old specific phobia participants (n=32 spider/snake phobia; n=14 claustrophobia) and gradually exposed them to their feared object or situation while measuring hormonal (ACTH and cortisol) and subjective (emotional distress, perceived control) responses. Utilizing a dyadic yoked design, we compared HPA reactivity when the pace of exposure was controlled by participants to identical exposure given to matched participants in the absence of control. Results showed that phobic fear exposure generated intense emotional distress without a corresponding increase in HPA axis activity. Although our actual manipulation of control failed to impact HPA responses, perceived control during exposure was associated with lower cortisol, an effect that was moderated by actual availability of stressor control. Our findings replicate Curtis' findings and challenge the still common but unsupported assumption that HPA axis activity reflects subjective distress. These results also highlight the importance of both perceived and actual aspects of stressor control in understanding what is truly "stressful" to the HPA axis system.
Implementation and Outcomes of a Community-Based Pulmonary Rehabilitation Program in Rural Appalachia.

PURPOSE To report on the implementation and clinical outcomes of a community-based pulmonary rehabilitation program in rural Appalachia. METHODS Three rural health centers and a large referral hospital worked together to establish pulmonary rehabilitation services based on AACVPR guidelines. Each site hired at least 1 respiratory therapist. To measure clinical outcomes, a retrospective medical record study compared pre- and post-program values for the modified Medical Research Council dyspnea level, 6-minute walk test (6MWT), negative inspiratory force (NIF), respiratory disease knowledge, St George Respiratory Questionnaire (SGRQ), BODE index (body mass index, airflow obstruction, dyspnea and exercise capacity), and smoking status. The percentages of persons completing the program and participating in maintenance exercise after the program were recorded. RESULTS During the first 20 months of the program, 195 unduplicated persons with qualifying chronic lung diseases started the program. Of these, 111 (57%) completed the program. Mean improvements for all 6 measures were highly significant (P < .001) and compared favorably with published results from hospital-based programs: dyspnea level, -1.2; 6MWT, +259 ft; NIF, +11.3 cm H2O; knowledge test, +1.9; SGRQ, -6.2; BODE index, -1.1. Of the 23 smokers, 5 quit by the end of the program. CONCLUSIONS Community-based pulmonary rehabilitation in rural health centers is feasible and achieves clinical outcomes similar to programs in large hospitals and academic centers. Furthermore, the addition of respiratory therapists to these primary care teams provides important collateral benefits for the evidence-based care of patients with chronic lung diseases.
Geriatric Hip Fractures

Hip fractures in the elderly are a significant public health concern, especially in the setting of the aging population. The term hip fracture encompasses multiple different fracture patterns, including femoral neck fractures, intertrochanteric hip fractures, and subtrochanteric hip fractures. This chapter delineates the key factors in management of hip fractures in the elderly, including fracture classification, medical and surgical management, as well as postoperative management and preventative measures.
Ideas of Race in Twentieth Century American and Continental Philosophy

After World War II, American and continental philosophers addressed race in progressive ways that avoided modern science. W.E.B. Du Bois pioneered a methodology of looking for social causes of social circumstances, such as conditions of African Americans living in slums. Alain Locke and William T. Fontaine followed a more theoretical pragmatic tradition. Cornel West, whose idea of prophecy is not prediction, but criticism, has furthered Du Bois’s sense of black destiny. The analysis of experience in Husserl’s phenomenology was developed as existentialism in Franz Fanon’s focus on white supremacy and Jean-Paul Sartre’s analysis of French anti-Semites. Hegel’s master-slave dialectic continues to motivate analyses of racism. Black theological existentialism is egalitarian in a spiritual dimension.
Regulation of the Adenylate Cyclase Signalling Pathway: Potential Role for the Phosphorylation of the Catalytic Unit by Protein Kinase A and Protein Kinase C

We have investigated the phosphorylation of the pure catalytic unit of adenylate cyclase by cyclic AMP-dependent protein kinase (PKA) and Ca2+/phospholipid-dependent protein kinase (PKC). The catalytic unit of adenylate cyclase from bovine striatum was purified to apparent homogeneity by sequential affinity chromatography on forskolin-Sepharose and wheat germ aggulutinin-agarose to a specific activity of 1.5 μmol.mg-1.min-1. The enzyme migrates as a single band of M ~160,000 on sodium dodecyl sulfate-polyacrylamide electrophoresis gels and co-elutes with adenylate cyclase activity on steric-exclusion HPLC. The purified catalytic unit can be co-reconstituted with purified β2-adrenergic receptor and stimulatory guanine nucleotide regulatory protein (GS) resulting in their functional coupling. The enzyme can be phosphorylated by both PKA and PKC up to 0.9 mol of phosphate/mol of enzyme. Phosphorylation of the catalytic unit by PKA reduces the Gpp(NH)p-stimulated activity of the enzyme by 30% when co-reconstituted with GS, whereas PKC-phosphorylation of the enzyme enhances this activity by 25%. These results suggest that hormone-sensitive adenylate cyclase systems may be regulated in vivo by PKA- and PKC-dependent phosphorylation of their catalytic units.
Advanced Techniques of Vasoepididymostomy

With advances in surgical technique and the development of microsurgical techniques, modern vasoepididymostomy allows us to accurately approximate the mucosa of a single epididymal tubule to the mucosa of the vasal lumen. With this increased precision, we have been able to achieve even higher patency and pregnancy rates. Microsurgical vasoepididymostomy, however, is the most technically demanding procedure in all of microsurgery. In virtually no other operation are results so dependent upon technical perfection. Thus, microsurgical vasoepididymostomy should only be attempted by an experienced microsurgeon who performs a sufficient volume of microsurgery. Modern IVF–ICSI has opened up reproductive options for those couples desiring fertility. This has caused some to question the need for advanced reconstructive reproductive tract surgery. However, in the hands of experienced microsurgeons, vasoepididymostomy is a safe, effective method of reconstruction for patients who do not want to undergo IVF or desire multiple children.
Refugees’ Rights: Capital, Óscar Martínez’s The Beast, Gianfranco Rosi’s Fuocoammare, and the “Problem” of the Surplus Population

In this chapter, I examine the inchoate articulation of rights in two recent texts about refugees: Martinez’s The Beast, a work of investigative journalism and a compelling account of the journey of Central American refugees across Mexico, and Rosi’s film, Fuocoammare, a record of those who, seeking refuge, attempt to make the treacherous crossing from North Africa to the island of Lampedusa. I suggest that though these narratives are deeply moving they place insufficient emphasis on a radical analysis of the conditions that lead to migration in the first place: for instance, they fail to explore how refugees’ rights can be negotiated within a larger imperial global narrative that is inextricably linked to the production and regulation of surplus populations. I conclude that the two texts relegate human rights issues to a mode of storytelling that leaves little room for the sort of understanding and analysis necessary for effecting structural change.
Development of a periodontitis risk assessment model for primary care providers in an interdisciplinary setting

Background Periodontitis (PD), a form of gum disease, is a major public health concern as it is globally prevalent and harms both individual quality of life and economic productivity. Global cost in lost productivity is estimated at US$54 billion annually. Moreover, current PD assessment applies only after the damage has already occurred. Objective This study proposes and tests a new PD risk assessment model applicable at point-of-care, using supervised machine learning methods. Methods We compare the performance of five algorithms using retrospective clinical data: Naive Bayes (NB), Logistic Regression (LR), Support Vector Machine (SVM), Artificial Neural Network (ANN), and Decision Tree (DT). Results DT and ANN demonstrated higher accuracy in classifying the patients with high or low PD risk as compared to NB, LR and SVM. The resultant model with DT showed a sensitivity of 87.08% (95% CI 84.12% to 89.76%) and specificity of 93.5% (95% CI 91% to 95.49%). Conclusions A predictive model with high sensitivity and specificity to stratify individuals into low and high PD risk tiers was developed. Validation in other populations will inform translational value of this approach and its potential applicability as clinical decision support tool.
Taiwanese Water and Korean Ink: Contemporary Ink Painting in Taiwan and Korea

AbstractContemporary art in Korea and Taiwan is influenced by two historical contexts: the acceptance of Western modernization and the progress of nationalism. These trends contradicted each other ...
Aspartic proteinases in gastric mucosa of the rat: Absence of pepsinogen I, genetic polymorphism of pepsinogen II, and presence of slow-moving proteinase

We have examined relationships among the aspartic proteinases in rat and human gastric mucosa by electrophoretic analysis in polyacrylamide gel and by immunoblotting and immunohistochemical staining using rabbit antisera to human pepsinogen I (PG I), pepsinogen II (PG II), and slow-moving proteinase. By electrophoretic analysis, the major proteolytic bands in mucosal extracts from each of three strains of rats had rates of anodal migration that were similar to the fastest migrating isozymogens of human PG I. However, immunoblots revealed that these bands and several minor proteolytic bands with slower rates of anodal migration reacted with antiserum to PG II. Two proteolytic bands in rat gastric mucosa that migrated concurrently with human slow-moving proteinase reacted with antihuman slow-moving proteinase reacted with antihuman slow-moving proteinase. None of the proteolytic bands in rat gastric mucosa reacted with anti-PG I. By immunohistochemical staining, anti-PG I failed to stain any cells in rat fundic gland or antral mucosa. By contrast, anti-PG II stained mucus neck and chief cells in fundic gland mucosa and pyloric gland cells in antral mucosa, and anti-slow-moving proteinase stained surface and foveolar epithelial cells throughout the stomach. The results indicate that the gastric mucosa of the rat does not contain PG I.
Experimental thermodynamics, surface and transport properties of liquid Ag-Ge alloys

Abstract The aim of this study is to correlate the thermodynamics of liquid Ag-Ge alloys with their thermophysical properties such as the surface tension, viscosity, electrical resistivity and microscopic functions. For this purpose the Quasi-Chemical Approximation (QCA) for the regular solution and Faber-Ziman theory have been applied to describe the mixing behaviour of Ag-Ge melts in terms of the energetics and structure. Concerning the Ag-Ge system, the most important is Ag-24.5Ge (in at %) eutectic alloy, widely used as a brazing filler material. The melting temperature and the heat of melting of Ag-Ge eutectic alloy were measured by Differential Scanning Calorimetry (DSC). From a technological point of view, particular attention should be paid to the surface tension, a key property of the joining processes. Accordingly, the QCA and Butler’s model calculations have been done and subsequently, the model predicted values were compared to available literature data.
A single amino acid enzyme

Enzymes require many, often hundreds, of amino acid residues arranged in a protein fold to promote catalysis. Now, self-assembly of a single amino acid — phenylalanine — in the presence of zinc is shown to form supramolecular structures that promote hydrolysis better than natural enzymes on a weight basis.
A review of dolomite catalyst for biomass gasification tar removal

Abstract Biomass gasification derived syngas could be used for different important industrial applications such as running internal combustion engine, generating electricity, and producing liquid hydrocarbon by Fisher-Tropsch method. The major drawback of syngas production through biomass gasification is the presence of contaminants such as hydrogen sulfide, hydrogen chloride, particulate matter, tar, and other undesired compounds in syngas. Tar is the most difficult to remove from syngas among all of the contaminants and causes severe problems in the downstream syngas applications. Researchers have been investigating different catalysts for removing tars for the last several decades. Dolomite is one of the widely studied catalysts for removing tar from syngas. Numerous research works have been conducted on the effectiveness of dolomite, calcined dolomite and combination of dolomite with other catalysts for removing tar from syngas. In this review, a detailed study on the dolomite catalyst has been conducted. Different aspects of dolomite catalyst such as calcination, mechanism of catalysis, in-situ vs ex-situ use, major problems (attrition, elutriation and coke formation), comparative strength, and the effectiveness of dolomite when used in combination with other catalysts have been studied and presented.
Chapter 10 – Exergy Analysis Applied toGeothermal Power Systems

Publisher Summary This chapter offers an introduction to the fundamental principles of exergy analysis, which is based on the Second Law of thermodynamics. It presents open systems operating in steady state. These are the applications encountered in all types of power plants, including geothermal power plants, once they reach their design operating conditions. These principles also may be used to assess refrigeration plants, air-conditioning systems, and many other common engineering process plants. After the basic working equations are derived, it examines some of the components usually found in geothermal plants to illustrate the use of these principles. Exergy analysis is the best tool for finding those elements within a plant that are most in need of redesign from an efficiency point of view. Exergy analysis relies strongly on the Second Law of thermodynamics. The study derives equations that express how closely a system comes to meeting thermodynamic ideality. The technique involves isolating the system (as a “free-body” in the language of mechanics) and performing an exergy accounting analysis. The system is assumed to operate in steady state with several mass flows into and out of the system.
Intraspecific Variation in Growth and Reproduction of the Marine Leech, Heptacyclus buthi.

Heptacyclus buthi was harvested from fish hosts in rocky intertidal zones of Sonoma and Marin Counties, California, in October 2008 (n = 162) and October 2010 (n = 51). The size of the leeches was quantified using a method that approximated the sagittal cross-section of each specimen. Size-frequency curves were modeled to estimate the number of size-class cohorts in each year. If H. buthi is an annual species like many of its relatives, the single cohort modeled for in 2010 and the comparable "older" cohort in 2008, both with a broad range of sizes, may represent 1 component of its reproductive life history. A second, younger, more-numerous, less-variable cohort modeled from the 2008 sample may represent a second reproductive bout during that year that was prevented in the subsequent La Nina period of 2010-2011.
Ultra-sensitive RDT performance and antigen dynamics in a high-transmission Plasmodium falciparum setting in Mali

The recent expansion of tools designed to accurately quantify malaria parasite-produced antigens has enabled us to evaluate the performance of rapid diagnostic tests (RDTs) as a function of the antigens they detect—typically histidine rich protein 2 (HRP2) or lactate dehydrogenase (LDH). For this analysis, whole blood specimens from a longitudinal study in Bancoumana, Mali were used to evaluate the performance of the ultra-sensitive HRP2-based Alere™ Malaria Ag P.f RDT (uRDT). The samples were collected as part of a transmission-blocking vaccine trial in a high transmission region for Plasmodium falciparum malaria. Furthermore, antigen dynamics after successful anti-malarial drug treatment were evaluated in these samples using the Q-Plex Human Malaria Array (4-Plex) to quantify antigen concentrations. The uRDT had a 50% probability of a positive result at 207 pg/mL HRP2 [95% credible interval (CrI) 160–268]. Individuals with symptomatic infection remained positive by uRDT for a median of 33 days [95% confidence interval (CI) 28–47] post anti-malarial drug treatment. Biphasic exponential decay models accurately captured the population level post-treatment dynamics of both HRP2 and Plasmodium LDH (pLDH), with the latter decaying more rapidly. Motivated by these differences in rates of decay, a novel algorithm that used HRP2:pLDH ratios to predict if an individual had active versus recently cleared P. falciparum infection was developed. The algorithm had 77.5% accuracy in correctly classifying antigen-positive individuals as those with and without active infection. These results characterize the performance of the ultra-sensitive RDT and demonstrate the potential for emerging antigen-quantifying technologies in the field of malaria diagnostics to be helpful tools in distinguishing between active versus recently cleared malaria infections.
A Multi-Scale Approach to Modeling E. coli Chemotaxis

The degree to which we can understand the multi-scale organization of cellular life is tied to how well our models can represent this organization and the processes that drive its evolution. This paper uses Vivarium-an engine for composing heterogeneous computational biology models into integrated, multi-scale simulations. Vivarium's approach is demonstrated by combining several sub-models of biophysical processes into a model of chemotactic E. coli that exchange molecules with their environment, express the genes required for chemotaxis, swim, grow, and divide. This model is developed incrementally, highlighting cross-compartment mechanisms that link E. coli to its environment, with models for: (1) metabolism and transport, with transport moving nutrients across the membrane boundary and metabolism converting them to useful metabolites, (2) transcription, translation, complexation, and degradation, with stochastic mechanisms that read real gene sequence data and consume base pairs and ATP to make proteins and complexes, and (3) the activity of flagella and chemoreceptors, which together support navigation in the environment.
Association of Chronic Myelogenous (Basophilic) Leukemia and the BCR/ABL Mutation in a Yucatan Barrow ( Sus scrofa domestica ).

Background: Chronic myelogenous leukemia (CML) is a clonal proliferative disorder of the myeloid, megakaryocyte, and erythroid lineages. The onset and subsequent progression of CML is well-described in humans. There is comparably little information surrounding CML progression in veterinary species, including Yucatan miniature swine that are common for preclinical pharmaceutical and device testing. In humans, more than 90% of CML cases are associated with a chromosomal translocation that results in the Philadelphia gene (BCR/ABL mutation). In this report, the presence of the Philadelphia gene in a Yucatan burrow was confirmed in white blood cells collected prior to onset of clinical signs with primers designed from the human BCR/ABL sequence. Case Presentation: A 24 month old, 70 kg, Yucatan barrow received a prefabricated bovine cortical bone xenograft following a unilateral zygomatic ostectomy for a preclinical study. Complete blood count and serum chemistries were performed prior to and 28, 53, 106, and 129 days after facial surgery. Fifty three days after surgery, a bone marrow biopsy was performed due to anorexia, severe basophilia, and mild anemia. A finding of a moderate increase in basophilic precursors in bone marrow cytology was followed by lymphocyte immunophenotyping via flow cytometry and RT-PCR amplification of the Philadelphia gene in white blood cell samples from the affected barrow and an unaffected barrow in the same treatment group. Bone marrow, lymph node, liver, spleen, lung, kidney, and adrenal gland lesions of mostly myeloblasts were identified after the affected barrow died 146 days after surgery. Flow cytometry confirmed lymphopenia and suggested basophilia, and RT-PCR established the presence of the BCR/ABL gene. Conclusions: The information in this report confirms the presence of the BCR/ABL mutation and documents progression of chronic myelogenous (basophilic) leukemia from a chronic phase to a terminal blast crisis in an adult Yucatan barrow. The natural occurrence and progression of CML associated with the BCR/ABL mutation in miniature swine establishes potential for future porcine models of human CML. The information also establishes a genetic test to confirm porcine CML to prevent inadvertent attribution of clinical signs to treatment complications during preclinical testing.
Identifying different phenotypes in takotsubo cardiomyopathy by latent class analysis

Aims This study sought to determine whether clinical clusters exist in takotsubo cardiomyopathy. Takotsubo cardiomyopathy (TCM) is a heterogeneous disorder with a complex, poorly understood pathogenesis. To better understand the heterogeneity of TCM, we identified different clinical phenotypes in a large sample of TCM patients by using latent class analysis (LCA). Methods and results Using the National Inpatient Sample (NIS) database, we identified 3139 patients admitted to hospitals in 2016-2017 with a primary diagnosis of TCM. We performed LCA based on several patient demographics and comorbidities: age, sex, hypertension, hyperlipidaemia, diabetes mellitus, obesity, current smoking, asthma, chronic obstructive pulmonary disease (COPD), and anxiety and depressive disorders. We then repeated LCA separately with the NIS 2016 and 2017 data sets and performed a robust test to validate our results. We also compared in-hospital outcomes among the different clusters identified by LCA. Four patient clusters were identified. C1 (n = 1228, 39.4%) had the highest prevalence of hyperlipidaemia (93.4%), hypertension (61.6%), and diabetes (34.3%). In C2 (n = 440, 14.0%), all patients had COPD, and many were smokers (45.8%). C3 (n = 376, 11.8%) largely comprised patients with anxiety disorders (98.4%) and depressive disorders (80.1%). C4 (n = 1097, 34.8%) comprised patients with isolated TCM and few comorbidities. Among all clusters, C1 had the lowest in-hospital mortality (1.0%) and the shortest length of stay (3.2 ± 3.1 days), whereas C2 had the highest in-hospital mortality (3.4%). Conclusions Using LCA, we identified four clinical phenotypes of TCM. These may reflect different pathophysiological processes in TCM. Our findings may help identify treatment targets and select patients for future clinical trials.
HOPE AND DESPAIR

A psychology of hope and despair is offered, integrating findings from recent psychological research in application to the interpretation of unrest among youth in the 1960s, of present socially problematic behavior, and of response to life under threat of nuclear holocaust. Survey data suggest a complex pattern: the majority of youth are hopeful about their own immediate future, but far fewer are optimistic about their nation and the world. Implications for individual action and social policy are offered.
Securing the Physical Layer in the OFDM-Based Internet of Things (IoT) by Using Frequency Hopping Technique

The physical layer security in the context of the internet of things is still one of the challenges due to the resource constraints of the end terminals and the IoT network heterogeneity. Although it has been adopted by different wireless applications due to its high spectral efficiency, the OFDM physical layer remains a challenge. The frequency hopping technique is used to protect the nodes from jamming and eavesdropping attacks. The cyclic prefix manipulation has been simulated against different time-delayed paths and the simulated results compared to the theoretical ones. The comparison shows a close match and the guard width encryption mechanism worked as desired.
Critically ill COVID-19 patients exhibit peripheral immune profiles predictive of mortality and reflective of SARS-COV-2 viral burden in the lung

Summary Despite extensive analyses, there remains an urgent need to delineate immune cell states that contribute to mortality in critically ill Coronavirus disease 2019 (COVID-19) patients. Here, we present high-dimensional profiling of blood and respiratory samples in severe COVID-19 patients to examine the association between cell-linked molecular features and mortality outcomes. Peripheral transcriptional profiles by single-cell RNAseq based deconvolution of immune states are associated with COVID-19 mortality. Further, persistently high levels of an interferon signaling module in monocytes over time leads to subsequent concerted upregulation of inflammatory cytokines. SARS-CoV-2 infected myeloid cells in the lower respiratory tract upregulate CXCL10, leading to a higher risk of death. Our analysis suggests a pivotal role for viral infected myeloid cells and protracted interferon signaling in severe COVID-19.
Medical expulsive therapy for pediatric urolithiasis: Systematic review and meta-analysis

Summary Objective Kidney stone disease has become more common among children and young adults. Despite its well-documented success in adults, published success rates of medical expulsive therapy (MET) for pediatric urolithiasis vary widely. Our objective was to determine whether the aggregated evidence supports the use of MET in children. Methods We searched the Cochrane Controlled Trials Register, clinicaltrials.gov , MEDLINE, and EMBASE databases, and recently presented meeting abstracts for reports in any language. In addition, the bibliographies of included studies were then hand-searched. The protocol was prospectively registered at PROSPERO (CRD42013005960). Inclusion criteria were children (aged ≤ 18 years) with urolithiasis treated with medications with the specific goal of increasing spontaneous stone passage rate, including but not limited to alpha-adrenergic blockers (e.g., tamsulosin or doxazosin), calcium channel blockers (e.g., nifedipine), or other adjuvant medications (e.g., steroids or tolterodine). Manuscripts were then assessed and data abstracted in duplicate, with differences resolved by the senior author. Risk of bias was assessed using standardized instruments. Descriptive statistical analyses were performed as appropriate. Results We identified 11,197 studies, five of which (3 randomized controlled trials, 2 retrospective cohorts) were included in the pooled meta-analysis. Although we found little evidence of significant publication bias, we were unable to assess the likelihood of other forms of bias (allocation, selection) for most included studies due to reporting limitations. The pooled results demonstrate that MET significantly increased the odds of spontaneous stone passage (OR 2.21, 95% CI 1.40–3.49). Between-study heterogeneity was not statistically significant (I2 = 14%, p = 0.36). Bivariate meta-regression models revealed no significant association between the likelihood of stone passage and study COI (p = 0.9), study country (p = 0.7), patient age (p = 0.4), patient gender (p = 0.4), duration of follow-up (p = 0.3), or stone size (p = 0.7). Side effects of MET were reported to be minimal. Relatively few patients reported any adverse effects at all; the most commonly reported issue was somnolence. Concerns about biases affecting the published outcomes of the included studies exist due to the low quality of the randomized controlled trials reviewed for analysis. However, there was little visual evidence of publication bias noted on the funnel plot, as confirmed by the Begg test (p = 0.5). Conclusions Consistent with the adult literature, pediatric studies demonstrate that treatment with MET results in increased odds of spontaneous ureteral stone passage and a low rate of adverse events. Although the accumulated literature is limited by inconsistent and/or incomplete reporting, there is nonetheless a clear, cumulative positive effect of MET on stone passage among children. The available evidence thus supports a prominent role for MET in treatment algorithms for pediatric urolithiasis.
Active avoidance conditioning with dorsal central gray stimulation in a place preference paradigm

Avoidance conditioning in response to aversive dorsal central gray stimulation was examined in a simple place preference task that minimized response demands and provided highly salient environmental cues. In contrast to shuttlebox avoidance learning with central gray stimulation, a high incidence of active avoidance learning was observed. The results suggest that poor avoidance in a shuttlebox task with central gray stimulation reflects task complexity rather than a fundamental inability to associate environmental cues with the consequences of central gray stimulation.
Metabolic dependence of photoreceptors on the choroid in the normal and detached retina.

Purpose This article assesses the hypothesis that the high blood flow rate and low O(2) extraction associated with the choroidal circulation are metabolically necessary and explores the implications of the spatial relationship between the choroid and the photoreceptors for metabolism in the normal and detached retina. Methods The O(2) distribution across the retinal layers was previously measured with O(2)-sensitive microelectrodes in cat. Profiles were fitted to a diffusion model to obtain parameters characterizing photoreceptor O(2) demand. This was a study of simulations based on those parameters. Results Photoreceptor inner segments have a high O(2) demand (QO(2)), and they are far (20 to 30 microm) from the choroid. These unusual conditions require a large O(2) flux to the inner segments, which in turn requires high choroidal oxygen tension (PO(2)), high choroidal venous saturation (ScvO(2)), low choroidal O(2) oxygen extraction per unit volume of blood, and a choroidal blood flow (ChBF) of at least 500 ml/100 g-min. Movement of the inner segments further from the choroid, which occurs in a retinal detachment, severely reduces the ability of the inner segments to obtain O(2), even for detachment heights as small as 100 microm. Depending on detachment height and assumptions about choroidal and inner retinal PO(2) during elevation of inspired O(2) (hyperoxia), hyperoxia is predicted to partially or fully restore photoreceptor QO(2) during a detachment. Conclusions The choroid is not overperfused, but requires a high flow rate to satisfy the normal metabolic demand of the retina. Because the oxygenation of the photoreceptors is barely adequate under normal conditions, detachment has serious metabolic consequences. Hyperoxia is predicted to have clinical benefit during detachment.
Quality-aware service delegation in automated web service composition: an automata-theoretic approach

Automated Web Service Composition has gained a significant momentum in facilitating fast and efficient formation of business-to-business collaborations where an important objective is the utilization of existing services to respond to new business requirements in a timely manner. In this context, the service delegation problem can be formulated as follows: When a user poses a sequence of requests to a "service community", how to delegate the requests to the available services registered in the community so that the user requests are satisfied via a collaboration of these services. Here, we present a formal analysis of the constrained service delegation problem where users also provides a set of quality constraints about the delegation of their requests. We follow the "Roman" service composition framework and extend it with a QoS model. We use the Presburger arithmetic to specify constraints. We show that there exists a linear time algorithm for the service delegation problem. In fact, this algorithm is a finite memory algorithm that solves two variations of the service delegation problem by reading the activity sequence in two or multiple passes. We also show that these results are tight in the sense that the number of passes can't be further reduced. We also prove that the constrained service delegation problem can be solved in polynomial time in the number of service requests and delegation constraints.
Pathway and surface mechanism studies of 1,3-butadiene selective oxidation over vanadium- molybdenum-oxygen catalysts

The partial oxidation of 1,3-butadiene has been investigated over VMoO catalysts synthesized by sol-gel techniques. Surface areas were 9-14 m{sup 2}/g, and compositions were within the solid solution regime, i.e. below 15.0 mol % MoO{sub 3}/(MoO{sub 3} + V{sub 2}O{sub 5}). Laser Raman Spectroscopy and XRD data indicated that solid solutions were formed, and pre- and post-reaction XPS data indicated that catalyst surfaces contained some V{sup +4} and were further reduced in 1,3-butadiene oxidation. A reaction pathway for 1,3-butadiene partial oxidation to maleic anhydride was shown to involve intermediates such as 3,4-epoxy-1-butene, crotonaldehyde, furan, and 2-butene-1,4-dial. The addition of water to the reaction stream substantially increased catalyst activity and improved selectivity to crotonaldehyde and furan at specific reaction temperatures. At higher water addition concentrations, furan selectivity increased from 12% to over 25%. The catalytic effects of water addition were related to competitive adsorption with various V{sub 2}O{sub 5}-based surface sites, including the vanadyl V=O, corner sharing V-O-V and edge sharing V-O oxygen. Higher levels of water addition were proposed to impose acidic character by dissociative adsorption. In addition, a novel combinatorial synthesis technique for VMoO was used to investigate the phase transitions of V{sub 2}O{sub 5}, solid solutions of Mo in V{sub 2}O{sub 5}, V{sub 9}Mo{sub 6}O{sub 40}, and other reduced VMoO compounds, characterized by laser Raman spectroscopy. The natural composition gradient imposed by the sputter deposition apparatus was used to create VMoO arrays containing 225 samples ranging from 7.0-42 mol% MoO{sub 3}/(V{sub 2}O{sub 5} + MoO{sub 3}), determined by EDS analysis.
Diet and Blood Pressure--The Paradigm Shift

We all know that we shouldn9t put too much salt on our food because it might cause our blood pressure to go up. In his Perspective, McCarron argues that the scientific evidence actually tells us something different: Salt has little effect on blood pressure, and the most effective diet-induced changes in blood pressure can be achieved with a menu low in fat but high in calcium, fruits, and vegetables.
Organo‐Phosph(on/in)ate‐Bridged Dimers of Vanadium(IV) Complexes with the Kläui Ligand: Synthesis and Characterization

A series of dinuclear organophosphorus-bridged vanadium(IV) complexes with the Klaui ligand, [CpPOMeCo]–, have been synthesized to model the catalytic activity of industrially used vanadium phosphate oxidation catalysts. Dimeric species of the general formula [(CpPOMeCo)V(O)(μ-O2PR′R″)]2 (R′,R″ = H, OH, Me, Ph, or 4-OPh-NO2), [(CpPOMeCo)V(O)]2(μ-oxalate), and [(CpPOMeCo)V(Cl)]2(μ-oxalate) are reported. These complexes have been characterized via spectral and magnetic analyses. The synthesis, characterization, and X-ray structures of the mononuclear vanadium(IV) complexes (CpPOMeCo)V(O)Cl(OH2) and(CpPOMeCo)V(O)(acac) are also presented here. [CpPOMeCo]–= η5-cyclopentadienyltris(dimethylphosphito-κ1P)cobaltate(III); acac = acetylacetonate.
Alignment of high rydberg states in hydrogen

We have measured the light yields and polarizations of the light emitted from several Balmer transitions in atomic hydrogen following beam foil excitation of protons at energies of 50 to 150 kev. The polarizations have been measured as a function of distance downbeam from the exciter foil for several transitions. The measurements indicate a very strong initial alignment which is then perturbed by surface fields out to several mm from the surface.
Seasonal and Diel Variability in Dissolved DNA and in Microbial Biomass and Activity in a Subtropical Estuary.

Dissolved DNA and microbial biomass and activity parameters were measured over a 15-month period at three stations along a salinity gradient in Tampa Bay, Fla. Dissolved DNA showed seasonal variation, with minimal values in December and January and maximal values in summer months (July and August). This pattern of seasonal variation followed that of particulate DNA and water temperature and did not correlate with bacterioplankton (direct counts and [3H]thymidine incorporation) or phytoplankton (chlorophyll a and 14CO2 fixation) biomass and activity. Microautotrophic populations showed maxima in the spring and fall, whereas microheterotrophic activity was greatest in late summer (September). Both autotrophic and heterotrophic microbial activity was greatest at the high estuarine (low salinity) station and lowest at the mouth of the bay (high salinity station), irrespective of season. Dissolved DNA carbon and phosphorus constituted 0.11 ± 0.05% of the dissolved organic carbon and 6.6 ± 6.5% of the dissolved organic phosphorus, respectively. Strong diel periodicity was noted in dissolved DNA and in microbial activity in Bayboro Harbor during the dry season. A noon maximum in primary productivity was followed by an 8 p.m. maximum in heterotrophic activity and a midnight maximum in dissolved DNA. This diel periodicity was less pronounced in the wet season, when microbial parameters were strongly influenced by episodic inputs of freshwater. These results suggest that seasonal and diel production of dissolved DNA is driven by primary production, either through direct DNA release by phytoplankton, or more likely, through growth of bacterioplankton on phytoplankton exudates, followed by excretion and lysis.
Computational Methods for Bone Mechanics Studies

The use of computational methods in the study of bone mechanics is described, with emphasis on the finite element method. In addition to the use of stan dard finite element methods for calcuiation of the dis placement, stress-and-strain environment in refined models of bone, the use of a "remodeling finite ele ment" is described to simulate the time course of changes in bone architecture that are induced by me chanical loading. The algorithm, which involves re peated finite element analyses over time, is shown to be feasible for use on supercomputing platforms.
Aircraft Design Markup Language for Multidisciplinary Aircraft Design and Analysis

The process of conceptual aircraft design has advanced tremendously in the past few decades due to rapidly developing computer technology. Today’s modern aerospace systems exhibit strong interdisci...
Genetic aspects of quantitative variation in the carbonic anhydrases of the pig-tailed macaque, Macaca nemestrina. I. Response to thyroxine.

Effects of thyroxine on incorporation of l-serine-C14 into four carbonic anhydrase isozymes (CA II, CA Ia, CA Ib, CA Ic) and hemoglobin were quantified in reticulocytes of Macaca nemestrina in vitro. Response to thyroxine differed significantly between CA Ia and two allelic variants (CA Ib and CA Ic) and the nonallelic isozyme (CA II). The effects of thyroxine on serine incorporation into hemoglobin and three of the carbonic anhydrase isozymes were shown to be nonlinear with thyroxine concentration.
Challenges facing academic dermatology: survey data on the faculty workforce.

Background There is a perception among many academic dermatologists that departments of dermatology face severe challenges with recruitment and retention of faculty. In an era when evidence points to a shortage of dermatologists and residency graduates have plentiful private practice offers in almost every geographic area, some fear that academic programs will face even steeper challenges attracting and keeping enough dermatologists on staff. Methods To compare the practice patterns of academic dermatologists with those of the dermatology workforce in other settings, data from the American Academy of Dermatology 2002 Practice Profile Survey were analyzed (1425 respondents, 35% response rate). Results The mean age of academic dermatologists (45.6 years) was younger than that of those in other practice settings (51.9 years solo practice, 49.0 years multispecialty group), and older age cohorts were significantly less likely to be working in academics (P Limitations Academic dermatologists reflected a relatively small proportion of survey respondents, and may not be representative of the nation's dermatology faculty (although the percentage of academics in the survey was similar to that in the overall workforce). Possible response biases could also have affected the survey results. Conclusions The survey results identify a number of differences between the practice patterns of academic dermatologists and their colleagues in other settings, and suggest that academic departments of dermatology may be facing unique workforce challenges.
Imaging in the era of molecular oncology

New technologies for imaging molecules, particularly optical technologies, are increasingly being used to understand the complexity, diversity and in vivo behaviour of cancers. 'Omic' approaches are providing comprehensive 'snapshots' of biological indicators, or biomarkers, of cancer, but imaging can take this information a step further, showing the activity of these markers in vivo and how their location changes over time. Advances in experimental and clinical imaging are likely to improve how cancer is understood at a systems level and, ultimately, should enable doctors not only to locate tumours but also to assess the activity of the biological processes within these tumours and to provide 'on the spot' treatment.
Expression and functional characterization of Metabotropic Glutamate Receptor Type 6 (mGluR6) in detergent micelles

Metabotropic glutamate receptors (mGluRs) are G protein coupled receptors which are implicated in different brain functions and dysfunctions including learning, memory, pain perception, neurodegeneration, schizophrenia and addiction. Metabotropic glutamate receptor type 6 (mGluR6) is a subtype of mGluRs which is exclusively expressed in ON-bipolar cells and is involved in night vision. Recent genome-wide association studies have discovered involvement of mGluR6 in heroin addiction. mGluR6 is emerging as a new drug target but structure-function relationships of this receptor and in general of mGluRs are poorly understood. These receptors have very low expression levels in their native cells and are only active in a membrane environment. The major problem in studying these receptors with biophysical approaches is in obtaining sufficient quantities of functional protein. To overcome this, we have constructed a tetracycline inducible mammalian stable cell line expressing full length human mGluR6. We optimized the detergent and buffer conditions required for mGluR6 purification. We are developing a reliable, quantitative in vitro assay for verifying the function of purified mGluR6 in different detergents. We have been successful in developing a medium scale expression and purification system of mGluR6. Preliminary data suggests that this receptor responds to a number of ligands relevant to its implicated role in vision and addiction with changes in activity and structure as evidenced by G protein binding and cysteine accessibility measurements, respectively.
Trade and Environment After Seattle: A Negotiation Agenda for the South

Developing countries have legitimate and significant apprehensions about the imposition of Northern environmental concerns on the international trade agenda. However, it is also becoming clear that even if it is possible to delay the induction of a stronger environmental focus within the global trade regime, it cannot be postponed indefinitely. The events at the Third Ministerial Meeting of the World Trade Organization suggest that the issue will have to be dealt with sooner rather than later. The relevant question for the South is no longer whether environmental concerns should influence trade rules, or even when, but how. This article argues that the developing countries cannot afford to dis-engage themselves from the discussion. It proposes a proactive and positive strategy for the South for future international negotiations: one that seeks the achievement of sustainable development through an active engagement of the developing countries in the trade and environment discourse.
Estimation of a linear transformation

Abstract : A problem arising in the earth sciences can be formulated as follows: Pairs (X(i), y(i)) of independent p-dimensional normal random vectors having common covariance matrix Sigma squared are observed, i=1,2,...,n. It is assumed that x(i) and y(i) have respective mean vectors Xi(i) and B Xi(i), i=1,2,...,n, where the p x 1 vectors Xi(1), Xi(2),...,Xi(n), the p x p matrix B, and Sigma squared are unknown, and the p x p matrix sigma is assumed known. Maximum likelihood estimators of the unknown parameters are obtained when n or = 2p, and their behavior is studied both theoretically and in simulations. Some other approaches to the estimation of functional relationships are also studied, and are shown to yield the same estimators as maximum likelihood. (Author)
Electronic states near the band gap for the GaAs(110) surface

Abstract The recent theoretical controversy regarding empty surface states at the GaAs cleavage plane is examined by the exact solution of several tight binding models applied to a semi-infinite crystal. We correlate the existence of an empty surface gap state with the anion p/cation p character of this state. This work isolates the specific properties of a Hamiltonian for GaAs which yield band gap states on a relaxed surface and clarifies the essential differences among current theoretical treatments.
Dielectric relaxation in ferroelectrics

Abstract Ferroelectrics are important multifunctional materials with applications ranging from high Er capacitors to non-volatile memory devices. Dielectric relaxation studies of ferroelectrics help elucidate the various mechanisms responsible for polarization. These insights are beneficial for materials engineering and tailoring of specific properties. In the present review, a comparison among the paraelectric, ferroelectric and physical states of the material are made. Compositional and dopant effects are also addressed. In ferroelectrics, the domain structure is shown to play a crucial role in determining both the nature and mechanism of the dielectric relaxation in the microwave region. At lower frequencies interfacial polarization dominates, especially for polycrystalline samples.