cssi/SciSciGPT-SciSciNet huggingface dataset:
Gloucester Fishery: insights from a group modeling intervention

System dynamics provides a powerful support mechanism for resolving problems in highly complex and dynamic contexts. Effectively building a system dynamics model in a client-group environment is a challenging task, particularly with a heterogeneous clientele and a variety of stakeholders inﬂuencing the boundaries of the model. In such environments, understanding and formulating central concerns is as important as it is challenging. This article describes a group model building initiative designed to study the implications of various policies aimed at revitalizing the ﬁshing industry in Gloucester, Massachusetts. While the iterative and interactive methods in this group modeling intervention helped ﬁshermen and community members to communicate effectively with one another, deﬁne problems and improve their understanding of the critical interactions in the system, the resulting model was used to help the Gloucester Community Development Cooperation to communicate potential impacts of a prospective ﬁsh factory to a wider audience. Copyright © 2004 John Wiley & Sons, Ltd.
Electrical coupling between cultured glomus cells of the rat carotid body: observations with current and voltage clamping

Electrically coupled pairs of cultured rat glomus cells were used. In one group of experiments, both cells were current-clamped. Delivery of positive or negative pulses to Cell 1 elicited appreciable voltage noise in this cell and large action potentials (probably Ca2+ spikes) in about 10% of them. Both passive and active electrical events spread to Cell 2, presumably through the gap junctions between them. The coupling coefficient (Kc) was larger for the spikes than for non-regenerative voltage noise. In another group of experiments, Cell 1 was current-clamped and Cell 2 was voltage-clamped at Cell 1 EM. Pulses of either polarity, delivered to Cell 1, produced current flow through the intercellular junction and allowed direct measurements of junctional currents (Ij) and total conductances (Gj). Ij had a mean value of about 12.5 pA and Gj of 391 pS. Unitary (presumably single channel) conductance (gj) was about 78 pS.
Infrared photodissociation spectroscopy of Agn(C6H6)m and Agn(C6D6)m clusters: evidence of adsorption-induced symmetry reduction in benzene

Abstract The infrared photodissociation spectra of Ag n (C 6 H 6 ) m and Ag n (C 6 D 6 ) m have been recorded near 10 μm for n = 3–7. For Ag n (C 6 H 6 ) m , we observe a feature around 1032 cm −1 , which is assigned to the allowed e lu fundamental of benzene. In addition, features are observed near 986 cm −1 in Ag n (C 6 H 6 ) m and 938 cm −1 in Ag n (C 6 D 6 ) m . These bands are assigned to the a 1g CC breathing mode - a transition which, while forbiddenfor a gas-phase benzene, is dipole allowed for benzene whose symmetry is reduced (to C 6v or lower) by adsorption.
Visualization of exception handling constructs to support program understanding

This paper presents a new visualization technique for supporting the understanding of exception-handling constructs in Java programs. To understand the requirements for such a visualization, we surveyed a group of software developers, and used the results of that survey to guide the creation of the visualizations. The technique presents the exception-handling information using three views: the quantitative view, the flow view, and the contextual view. The quantitative view provides a high-level view that shows the throw-catch interactions in the program, along with relative numbers of these interactions, at the package level, the class level, and the method level. The flow view shows the type-throw-catch interactions, illustrating information such as which exception types reach particular throw statements, which catch statements handle particular throw statements, and which throw statements are not caught in the program. The contextual view shows, for particular type-throw-catch interactions, the packages, classes, and methods that contribute to that exception-handling construct. The paper also presents a case study in which we evaluated a prototype of the visualization system on a small set of developers.
Nucleation and growth of fibres and gel formation in sickle cell haemoglobin

DEOXYGENATED sickle haemoglobin polymerizes into long 210-A diameter fibres that distort and decrease the deformability of red blood cells, and cause sickle cell disease. The fibres consist of seven intertwined double strands1–3. They can form birefringent nematic liquid crystals (tactoids)4 and spherulites5,6. Rheologiealiy, the system behaves as a gel7,8. The equilibria show a phase separation and a solubility9–14. The reaction kinetics show a delay time, are then roughly exponential and are highly dependent on concentration and temperature9,10,15–18, and accord with the double nucleation model5,19. But these conclusions are derived from macroscopic data, without direct observation of individual fibres. We have now used non-invasive video-enhanced differential interference contrast (DIC) and dark-field microscopy to observe nucleation, growth and interaction of sickle deoxyhaemoglobin fibres in real time. The fibres originate both from centres that produce many radially distributed fibres and on the surface of pre-existing fibres, from which they then branch. The resulting network is cross-linked and dynamic in that it is flexible and continues to grow and cross-link. Our results support most aspects of the double nucleation model.
Photoaffinity labeling of benzodiazepine receptors in rat brain with flunitrazepam alters the affinity of benzodiazepine receptor agonist but not antagonist binding.

: Recently, it was proposed that β-carbolines interact with a subset of benzodiazepine (BZD) binding sites in mouse brain. This postulate was based upon evidence showing changes in binding properties of the BZD receptor following photoaffinity labeling of membranes with flunitrazepam (FLU). Under conditions in which 80% of specific [3H]diazepam binding was lost in photolabeled membranes, specific [3H]propyl β-carboline-3-carboxylate ([3H]PCC) binding was spared. In this study, the binding of the BZD antagonists [3H]PCC, [3H]Ro15 1788 and [3H]CGS 8216 was examined in rat brain membranes following photoaffinity labeling with FLU. No significant changes in the apparent KD and small reductions in the Bmax of 3H antagonist binding were observed. However, in the same membranes, up to 89% of specific [3H]FLU binding was lost. When [3H]PCC (0.05 nM) was used to label the receptors in control and photolabeled membranes, the ability of BZD receptor agonists to inhibit [3H]PCC binding was greatly diminished in the photolabeled membranes. In contrast, the potency of BZD antagonists remained the same in both control and treated membranes. Based upon PCC/[3H]Ro15 1788 competition experiments, the ability of PCC to discriminate between BZD receptor subtypes was unaffected by photoaffinity labeling of cortical membranes. Overall, these findings suggest that β-carbolines do not interact with a subset of BZD binding sites per se, but may be a consequence of the differential interaction of BZD agonists and antagonists with BZD binding sites that have been photoaffinity labeled with FLU. A possible mechanism underlying this phenomenon is discussed. The ability of photolabeled membranes to differentiate between BZD agonists and antagonists provides a potential screen for agonist and antagonist activity in compounds that interact with the BZD receptor.
Membrane mucin Muc4 induces density dependent changes in Erk activation in mammary epithelial and tumor cells: Role in reversal of contact inhibition

The membrane mucin Muc4 has been shown to alter cellular behavior through both anti-adhesive effects on cell-cell and cell-extracellular matrix interactions and its ability to act as an intramembrane ligand for the receptor tyrosine kinase ErbB2. The ERK pathway is regulated by both cell-matrix and cell-cell adhesion. An analysis of the effects of Muc4 expression on ERK phosphorylation in mammary tumor and epithelial cells, which exhibit both adhesion-dependent growth and contact inhibition of growth, showed that the effects are density dependent, with opposing effects on proliferating cells and contact-inhibited cells. In these cells, cell-matrix interactions through integrins are required for activation of the ERK mitogenesis pathway. However, cell-cell interactions via cadherins inhibit the ERK pathway. Expression of Muc4 reverses both of these effects. In contact-inhibited cells, Muc4 appears to activate the ERK pathway at the level of Raf-1; this activation does not depend on Ras activation. The increase in ERK activity correlates with an increase in cyclin D(1) expression in these cells. This abrogation of contact inhibition is dependent on the number of mucin repeats in the mucin subunit of Muc4, indicative of an anti-adhesive effect. The mechanism by which Muc4 disrupts contact inhibition involves a Muc4-induced relocalization of E-cadherin from adherens junctions at the lateral membrane of the cells to the apical membrane. Muc4-induced abrogation of contact inhibition may be an important mechanism by which tumors progress from an early, more benign state to invasiveness.
LivingPlessey in the context ofBrown: Cultural politics and the rituals of separation

This article examines the rituals of exclusion present in some public schools in southern Georgia. While ostensibly desegregated nearly twenty years afterBrown, many of these schools still articulate the concept of “separate but equal” through ritualized curricular practices. Such acts fly in the face of the stated purposes of integrated public schools. The writer analyzes this phenomenon relative to ritual theory and poststructural conceptions of power. Working from the analytics of Foucault and the work of McLaren, the writer argues that regardless of the rationales of the stated discourse of inclusion, the discourse of exclusion and separation is clearly the dominant form of social practice. The writer then discusses the impact of these discursive practices relative to the continuing problem of self-imposed segregation in schools and posits some possible courses of action. Extended implications of these practices are illustrated through interviews concerning the symbolic inequalities extant throughout the region.
PIT-Tag Detection System for Large-Diameter Juvenile Fish Bypass Pipes at Columbia River Basin Hydroelectric Dams

Abstract We developed a prototype detection system with increased reading range for passive integrated transponder (PIT) tags. The system eliminates the need to route juvenile salmonids to sampling and collection facilities for detection and allows fisheries management greater flexibility in safely bypassing juvenile salmonids at dams. This technology can be applied to PIT-tag studies elsewhere, especially those directed at recovery of threatened and endangered salmonid populations. The system exceeded the intended goal of 95% tag-reading efficiency and yielded reading efficiencies near 100% for the four antennas combined. In tests using juvenile steelhead Oncorhynchus mykiss and subyearling Chinook salmon O. tshawytscha, the system worked as designed under a variety of release times and densities. Both direct and indirect methods were used to evaluate the system. The direct method used a known number of tagged fish released at a specific location and compared that number to the number of unique tag codes...
Essential biochemical design features of the fuel-sensing system in pancreatic β-cells

Abstract The β-cells of the pancreas control the blood levels of glucose and other nutrients by secreting insulin. They sense blood nutrient levels not by using a classical receptor-signaling system, but by detecting the products of nutrient metabolism. Mutations in this pathway can cause diabetes or hypoglycemia.
Electronic Transitions in Slow Collisions of Atoms and Molecules. II. Calculations of Wave Functions and Green's Functions in the Eikonal Approximation

Practical techniques are developed for evaluating wave functions and Green's functions using the eikonal approximation. It is assumed that the scattering angle is small. This provides a great simplification in analysis of the trajectory curves, radii of curvature, etc. A sequence of approximations and the use of variational principles are described. Numerical illustrations, particularly for proton-hydrogen-atom scattering, are given for several of the approximations.
A study of procedures for isolation and fractionation of plant cell walls

Abstract Three procedures have been developed and tested for quantitative isolation and fractionation of plant cell walls in tracer experiments using relatively small amounts of plant material. Avena seedlings photosynthetically labeled with C 14 were used as the test material. A cold water extraction at 0°C with an isolation based on a sucrose density gradient centrifugation was found to give well-defined fractions but appeared to allow slight hydrolysis of some components during isolation. Extraction in anhydrous glycerol at 0–5°C with differential centrifuging also gave rise to well-defined cell wall fractions but was subject to many technical difficulties arising from the high viscosity of the isolating medium. Isolation carried out in a solution of glycerol in ethylene glycol (1:4) at −20°C with differential centrifuging allowed excellent fractionation without apparent hydrolysis. Isolations and fractionations of the cell wall materials were carried out entirely by centrifugation techniques in the original homogenizing tubes, thereby avoiding transfer losses. Thus the procedures are well adapted for use in tracer experiments where limited amounts of plant material are used.
Parent-Child Interaction Therapy With a Spanish-Speaking Family

Abstract There is relatively little information on the treatment effectiveness of child behavior-management programs with Spanish-speaking populations. Though there are several empirically supported treatments available in English, research on the applicability of these programs in Spanish is virtually nonexistent. This single-case study discusses the application of Parent-Child Interaction Therapy (PCIT) with a Spanish-speaking mother-child dyad to address the child’'s externalizing behavior problems. Both observational and parent self-report data are presented. Results suggest that PCIT was effective in increasing positive parent behaviors, decreasing child behavior problems, and reducing parental stress level. Implications for future clinical and research work with Spanish-speaking families are discussed.
Computable trees, prime models, and relative decidability

We show that for every computable tree T with no dead ends and all paths computable, and every D >T 0, there is a D-computable listing of the isolated paths of T. It follows that for every complete decidable theory T such that all the types of T are computable and every D > T O, there is a D-decidable prime model of T. This result extends a theorem of Csima and yields a stronger version of the theorem, due independently to Slaman and Wehner, that there is a structure with presentations of every nonzero degree but no computable presentation.
Effects of cyclophosphamide alone and scheduled methotrexate-5-fluorouracil combination chemotherapy on transplantable R-3327 prostatic adenocarcinoma in F1 hybrid male rat.

Male F1 hybrid rats bearing the R-3327 transplantable adenocarcinoma demonstrating similar growth patterns within the original sample of animals were carefully separated into control and treatment groups for each growth pattern. This assured treatment of tumors with similar cell kinetics within each group. In one group, cyclophosphamide (100 mg/kg) was injected intraperitoneally once every four weeks for eight weeks (total of two doses). In the second group, methotrexate (7.5 mg/kg) followed in ninety minutes by 5 fluorouracil (50 mg/kg) were injected intraperitoneally once each week for eight weeks (total of eight doses). These drug dosages did not depress the white cell count of the animals, and they tolerated the medicines well. Excellent suppression of tumor growth was obtained in each group with the cyclophosphamide treatment group being significant at the 0.01 level and the methotrexate-5 fluorouracil treatment group being significant at the 0.05 level.
Social skills: A review of cognitive-behavioral training procedures with children

Abstract Thirty-one studies utilizing cognitive-behavioral procedures to train social skills were reviewed. The review was organized around six methodological issues: (a) age of subjects; (b) training procedures; (c) outcome measures; (d) research design; (e) evidence for generalization; and (f) social validation. Suggestions for future applied research are discussed, such as investigations regarding developmental changes in socially skilled behavior, increased use of multiple dependent measures, more intensive programming for generalization, and the establishment of the social importance of the effects of social skills training programs.
Effects of meridional variation on steady-state visual evoked potentials

Abstract Two experiments were carried out to assess the influence of meridional variations on the visually evoked potentials (VEPs) elicited by pattern alternation. The first experiment involved a comparison of the oblique effect obtained with grating and checkerboard stimuli. Greater amplitudes resulted using stimuli which contained vertically, as opposed to obliquely, oriented fundamental Fourier components. The second experiment revealed that the peak delay * of the VEP was markedly shorter when subjects wore cylindrical lenses oriented such that they emphasized a fundamental Fourier component of the checkerboard stimulus. These results underline the importance of describing complex patterned stimuli in terms of Fourier analysis when evaluating meridional aspects of visual function.
Toxicity studies and environmental impact assessment

There is abundant evidence that many factors can influence the toxicity of a particular pollutant including environmental fluctuations, season of the year, stage in life cycle, size, and sex. All of these factors should be assessed before making a judgment of the effect on natural populations. Such an assessment can be conceptualized using a simple population model through which“control gates” operate as functions of 1). the direct self-maintainance feedback from existing adult population biomass and 2). the recruitment of new individuals due to the maturation of larvae. By extracting general principles of organismic response to pollutants it is possible to incorporate the information into large-scale ecosystem models which would serve as working tools for answering environmental decision-making problems.
Identifying the origin of new gauge bosons at the Superconducting Super Collider.

We examine the ability of the detector of the Solenoidal Detector Collaboration (SDC) to identify the origin of a new neutral gauge boson {ital Z}{sub 2} in the TeV mass range at the Superconducting Super Collider. Specifically, given the measurements of the {ital Z}{sub 2} production cross section, width, and leptonic forward-backward asymmetry, together with their associated statistical and systematic errors, we address two related questions: (i) For two different extended electroweak models, up to what mass can their corresponding {ital Z}{sub 2} bosons be distinguished, and (ii) how well can the {ital Z}{sub 2} couplings be determined Our calculations include {ital O}({alpha}{sub {ital s}}{sup 2}) QCD, as well as oblique electroweak radiative corrections to the above quantities, and allow for uncertainties due to structure functions, detector efficiencies, lepton identification, luminosity measurement errors, and finite lepton-pair mass resolution, using the specifications of the SDC detector. Nine distinct classes of extended electroweak models are investigated and results are obtained for integrated luminosities of 10{sup 4} and 10{sup 5} pb{sup {minus}1}.
Formation Quotients of Aluminum Sulfate Complexes in NaCF3SO3 Media at 10, 25, and 50 °C from Potentiometric Titrations Using a Mercury/Mercurous Sulfate Electrode Concentration Cell

Mercury/mercurous sulfate electrode concentration cells (with liquid junction) are employed in this study to determine the formation constants of aluminum sulfate complexes, with the principal advantage that the change in the free sulfate concentration is measured directly without the need to know the standard potential of the electrode. Potentiometric titrations were conducted at temperatures of 10, 25, and 50 °C and ionic strengths of approximately 0.3, 0.5, and 1.0 molal in aqueous solutions of the inert 1:1 electrolyte sodium trifluoromethanesulfonate (NaTr). Stoichiometric molal formation quotients Q1 and Q2, respectively, for the reactions Al3+(aq) + SO42-(aq) ⇌ AlSO4+(aq) and Al3+(aq) + 2SO42-(aq) ⇌ Al(SO4)2-(aq) were determined. The values of log Q1 obtained from this work in NaTr media at ionic strengths of 0.3 and 1.0 mol·kg-1 and 50 °C (1.72 ± 0.08 and 1.35 ± 0.06, respectively) are in excellent agreement with the values (1.71 ± 0.2 and 1.32 ± 0.1) determined in NaCl media from the recent poten...
Elementary students' responses to questions about plant identification: Response strategies in children

Nine sixth-grade students were asked to identify plants seen in a set of slides and examined in two outdoor field trips. When the students did not know the correct common name for a plant (e.g., oak, dandelion), they relied on a variety of response strategies to deal with their lack of knowledge. Three patterns of response emerged when students lacked knowledge of names for plants. Student responses may represent avoidance strategies: avoidance of admission of ignorance, avoidance of being wrong, or avoidance of giving a name more abstract than the common name (e.g., tree, wildflower). These strategies did not result in names that would be acceptable to a science teacher, but the strategies had the effect of hiding the students' lack of knowledge or preventing a “wrong” answer. The study demonstrated that students prefer to identify plants at the generic level (e.g., calling a plant oak rather than tree), which suggests that elementary students should be introduced to the concept of genus (e.g., oak, lily) before being introduced to the more abstract levels of the botanical classification scheme (e.g., class monocot, dicot). © 1994 John Wiley & Sons, Inc.
Blood content of asymmetric dimethylarginine: new insights into its dysregulation in renal disease

Background. Plasma asymmetric dimethylarginine (ADMA), an endogenous inhibitor of nitric oxide synthase, is significantly elevated in patients with kidney disease and is a potential risk factor for cardiovascular disease. Here, we tested whether human whole blood (WB), as in rodent blood, can accumulate free ADMA and whether this accumulation is a function of disease burden. Methods. In 16 healthy control subjects (CO), 18 patients with ESRD and 18 matched hypertensive patients with normal renal function (HTN), we compared using highpressure liquid chromatography baseline plasma and WB supernatant (WBSUP) ADMA and symmetrical dimethylarginine (SDMA) concentrations and accumulation during a 5-h incubation. We measured protein turnover in incubated WBSUP to determine if proteolytic processes drive ADMA accumulation. Results. Elevated plasma ADMA was confirmed in ESRD andHTNpopulationswhilebasalWBSUPADMAwassignificantly higher in ESRD subjects than controls (P = 0.05 versus CO;P =0.02versusHTN).PlasmaSDMAfollowed a similar pattern. Incubation of WBSUP resulted in ADMA release from protein-incorporated stores while SDMA was unaffected. ADMA accumulation in ESRD samples was significantly greater than that in HTN (P = 0.03). CO and HTN men showed significantly greater ADMA accumulation than women (P = 0.01 and P = 0.003, respectively) but no gender difference was observed in the ESRD group (P = 0.26). ADMA accumulation correlated with ex vivo protein turnover (R = 0.76, P < 0.0001). Conclusions. Human blood is capable of releasing physiologically significant quantities of ADMA via proteolytic pathways. Dysregulated ADMA release from WB reservoirs may contribute to the distinctly high plasma ADMA levels in ESRD populations.
Too big and too interconnected to fail: historical and ethical analysis of sustainability risk to the US financial system

The financial crisis which manifested in the USA in 2008, revealed the extent to which the largest and most interconnected financial institutions in the USA had become ‘too big to fail’, i.e., so systematically and significantly interwoven with each other and the entire US and global financial and economic system that their very survival was seen as essential to the sustainability of the entire financial system and to public welfare. We argue that it is essential to understand the financial crisis that began in 2008 from a historical and ethical perspective. We conclude that, in light of individual and collective moral hazards, the overall governance framework that protects the sustainability of the financial system should explicitly adopt as a moral imperative the principle that any financial institution should be able to fail without such failure threatening the entire financial system.
Statistical computer-aided design for microwave circuits

A useful methodology for microwave circuit design is presented. A statistical technique known as Design of Experiments is used in conjunction with computer-aided design (CAD) tools to obtain simple mathematical expressions for circuit responses. The response models can then be used to quantify response trade-offs, optimize designs, and minimize circuit variations. The use of this methodology puts the designer's intelligence back into design optimization while making "designing for circuit manufacturability" a more systematic and straightforward process. The method improves the design process, circuit performance, and manufacturability. Two design examples are presented in context to the new design methodology.
Cultural considerations in adolescent suicide prevention and psychosocial treatment

Ethnic groups differ in rates of suicidal behaviors among youths, the context within which suicidal behavior occurs (e.g., different precipitants, vulnerability and protective factors, and reactions to suicidal behaviors), and patterns of help-seeking. In this article, the authors discuss the cultural context of suicidal behavior among African American, American Indian and Alaska Native, Asian American and Pacific Islander, and Latino adolescents, and the implications of these contexts for suicide prevention and treatment. Several cross-cutting issues are discussed, including acculturative stress and protective factors within cultures; the roles of religion and spirituality and the family in culturally sensitive interventions; different manifestations and interpretations of distress in different cultures; and the impact of stigma and cultural distrust on help-seeking. The needs for culturally sensitive and community-based interventions are discussed, along with future opportunities for research in intervention development and evaluation.
Bottlenecks and multiple introductions: population genetics of the vector of avian malaria in Hawaii.

Avian malaria has had a profound impact on the demographics and behaviour of Hawaiian forest birds since its vector, CuZex quinquefasciatus the southern house mosquito, was first introduced to Hawaii around 1830. In order to understand the dynamics of the disease in Hawaii and gain insights into the evolution of vector-mediated parasite-host interactions in general we studied the population genetics of Cx. quinquefasciatus in the Hawaiian Islands. We used both microsatellite and mitochondrial loci. Not surprisingly we found that mosquitoes in Midway, a small island in the Western group, are quite distinct from the populations in the main Hawaiian Islands. Howevel; we also found that in general mosquito populations are relatively isolated even among the main islands, in particular between Hawaii (the Big Island) and the remaining Hawaiian Islands. We found evidence of bottlenecks among populations within the Big Island and an excess of alleles in Maui, the site of the original introduction. The mitochondrial diversity was typically low but higher than expected. The current distribution of mitochondrial haplotypes combined with the microsatellite information lead us to conclude that there have been several introductions and to speculate on some processes that may be responsible for the current population genetics of vectors of avian malaria in Hawaii.
Mechanistic insights into reducing the weight of breast cancer.

Perspective on Jiang et al.,[p. 338][1] The prevalence of obesity, an established epidemiologic risk factor for many cancers including breast cancer in postmenopausal women ([1][2]), has increased dramatically over the past 30 years ([2][3]). Particularly alarming are the increasing rates of
Synthesis and Characterization of Rare Earth (Tb 3+ and Yb 3+ ) Doped CdS/ZnS Core/Shell Nanocrystals for Enhanced Photovoltaic Efficiency

CdS host nanocrystals with 4.2-5.5 nm in diameter have been synthesized from air stable precursors via a synthetic chemical route and doped with rare earth (RE) terbium (Tb 3+ ) and ytterbium (Yb 3+ ) ions. RE 3+ -doped CdS cores were shelled by ZnS layers of different thicknesses. The resulting core/shell nanocrystals show a complete broadband absorption below 400-460 nm to the deep UV region depending on the size of the cores. RE 3+ -doped CdS nanocrystals showed a red shift in the emission as observed under irradiation of 302 nm UV light and was confirmed by room temperature photoluminescence (PL) measurements. The nanocrystals were further characterized by x-ray diffraction (XRD), transmission electron microscopy (TEM), and energy dispersive x-ray (EDX) analysis. The results show that these RE 3+ -doped nanocrystals can be used as solar spectral matching downconversion material to enhance photovoltaic efficiency of existing solar cells.
Calcium Niobate Semiconductor Nanosheets as Catalysts for Photochemical Hydrogen Evolution from Water

We have studied the photochemical water splitting activity of individually dispersed, semiconductor nanosheets derived from the Dion−Jacobsen phase HCa2Nb3O10 by exfoliation with tetrabutylammonium hydroxide. The dimensions of the nanosheets are 0.001 × 1.2 × 1.2 μm3 based on TEM measurements and crystallographic data, and their band gap is determined as 3.53 eV based on the absorption band edge at 350 nm. When an aqueous suspension of the nanosheets is irradiated with light from a Hg lamp, hydrogen is produced at rates of up to 2.28 μmol/h with a quantum efficiency (QE) of 0.22%. No oxygen is evolved. Derivatization of the nanosheets with Pt nanoparticles increases the hydrogen production rate to 78.37 μmol (QE = 7.5%). Restacking of the nanosheets at low pH does not significantly affect the catalytic activity. Transient absorption measurements of the nanosheets reveal charge separation on a nanosecond time scale.
Body image dissatisfaction and disordered eating in black and white women.

Objective This study predicted and found that body image dissatisfaction and bulimic symptoms have a curvilinear relationship among undergraduate women. Results For the women in this sample, regardless of race, body image dissatisfaction correlated with bulimic symptoms, such that women who perceived themselves as bigger or smaller than the ideal body size for their ethnic group endorsed bulimic symptoms. Black and white women differed regarding their ethnic group's ideal body image and their self-perceptions of how they compared with the ideal image. Black women tended to report being underweight, whereas white women tended to report being overweight. Discussion The findings in this study suggest that some black women are not buffered against eating disorders as suggested in previous research. © 2003 by Wiley Periodicals, Inc. Int J Eat Disord 33: 342–350, 2003.
Mass Spectrometry Goes With the Flow: Mass Cytometry and Its Potentials in Regenerative Medicine

### Study Aim Numerous technical advances have characterized the proteomic field since it was first named in 1994.1 Some of the techniques that have driven the field, such as mass spectrometry, have undergone considerable technical development over the years. For instance, time-of-flight (TOF) mass analyzers date back to the first half of the 20th century.2 In the study described by Newell and colleagues3 a newly developed hybrid instrument, which combines a flow-cytometer with a TOF analyzer (cyTOF), was employed to characterize CD8+ T lymphocytes in humans. Notably, contrary to traditional flow-cytometry, where multiplexing (monitoring multiple analytes at the same time) is limited by the partial overlap of excitation/emission spectra of the different fluorophores, in this case the reporters that can be measured are many and more selective (little to no cross-talk). Finally, although, to my knowledge, this cutting-edge technique has not been applied yet in the cardiovascular research field, perhaps 1 application can be anticipated, in the field of cardiac regeneration. ### How Was the Aim Achieved? Newell and colleagues went about describing the heterogeneity of CD8+ T lymphocytes by enriching them from the peripheral blood of platelet aphaeresis donors. Two different approaches were employed to characterize the CD8+ population. One used mass cytometry, also referred to as cyTOF, due to the mass analyzer employed. In proteomics, TOF analyzers are associated most commonly to matrix assisted laser …
Time‐dependent three dimensional compressible convection with depth‐dependent properties

Using a spectral code, we have studied the time-dependent regime of three-dimensional anelastic compressible convection with depth-dependent thermal expansivity, viscosity and thermal conductivity in a wide box of size 5 x 5 x 1. Surface Rayleigh numbers up to 5 x 10 exp 6 have been considered. Very few cylindrical plumes are developed at the bottom but they join up collectively to form strong upwellings, which pulsate chaotically. Major descending flows occur in sheets which form rectangular planform at the top. The thermal and flow fields are dominated by large-scale features. The bottom 20 percent of the convecting layer is found to be superadiabatic.
Test Length in a Self-Testing Environment

Two ideas are Coupled to help determine the Pseudorandom test length in a self-testing environment. The first is that yield, defect level after test, and test coverage are related. Tbe second is that Fault Coverage as ta function of the number of pseudorandom test patterns can be approximated on semilogarithmic paper an exponential curve, with statistical confidence intervals. Merging these two concepts allows one to relate the shipped defect level as a function of the number of radomp pattterns and yield, With this knowledge, the test length of pseudorandom patterns Can be Predicted in a self-test environment.
The Rationale, Efficacy and Safety of Androgen Therapy in Older Men: Future Research and Current Practice Recommendations

Epidemiological studies indicate that normal male aging is associated with a gradual and variable decline in blood testosterone concentrations and unfavorable changes in muscle, bone, and fat that mimic those of androgen deficiency in young men. These age-related reductions in muscle and bone mass and increased fat mass may be responsible for other age-related changes, including decreased muscle strength and physical function, changes in metabolic function, and increased falls, fractures, and disability. Whether age-related relative androgen deficiency truly causes any of these features requires interventional studies specifically in older men, because aged tissues may not remain androgen sensitive nor is such treatment necessarily safe. A Medline search (years 1966 through January 2004, using search terms random and androgen), supplemented by subsequent reference searches of retrieved articles, identified randomized placebo-controlled studies of androgen therapy. These studies show that androgen replacement in older men increases muscle and reduces fat mass to a small degree, but to date has not improved muscle strength, physical function, or insulin sensitivity, nor does it convincingly improve bone density, although the latter effect is particularly dose responsive. However, idiosyncratic adverse effects, such as disordered sleep and breathing as well as polycythemia, are also dose responsive, suggesting that dose escalation to increase efficacy may create or aggravate undesirable side effects. Furthermore, the clinical safety of androgen therapy for cardiovascular and prostatic disease is uncertain. Under these circumstances, androgen supplementation is not recommended in healthy older men. However, interim recommendations are available to help guide appropriate and curb unnecessary androgen prescription for symptomatic older men with low serum testosterone levels.
Using tablet computers to teach evidence-based medicine to pediatrics residents: a prospective study.

Abstract Objective We sought to determine if tablet computers—supported by a laboratory experience focused upon skill-development—would improve not only evidence-based medicine (EBM) knowledge but also skills and behavior. Methods We conducted a prospective cohort study where we provided tablet computers to our pediatric residents and then held a series of laboratory sessions focused on speed and efficiency in performing EBM at the bedside. We evaluated the intervention with pre- and postintervention tests and surveys based on a validated tool available for use on MedEdPORTAL. The attending pediatric hospitalists also completed surveys regarding their observations of the residents' behavior. Results All 38 pediatric residents completed the preintervention test and the pre- and postintervention surveys. All but one completed the posttest. All 7 attending pediatric hospitalists completed their surveys. The testing, targeted to assess EBM knowledge, revealed a median increase of 16 points out of a possible 60 points ( P Conclusions This novel approach for teaching EBM to pediatric residents improved knowledge, skills, and behavior through the introduction of a tablet computer and laboratory sessions designed to teach the quick and efficient application of EBM at the bedside.
Anomalous behavior of l = 0 transitions in 98Mo(d,p) and 100Mo(d,t) reactions☆

Abstract The states of 99 Mo dominantly populated by l = 0 transitions in 98 Mo(d,p) and in 100 Mo(d,t) are not the same. The ratio S( d,t ) S( d,p ) for these states differs by a factor of 21 which is an order of magnitude larger than in any other known case. This represents a breakdown of the quasi-particle model.
Leptin deficiency suppresses MMTV-Wnt-1 mammary tumor growth in obese mice and abrogates tumor initiating cell survival

Obesity increases both the risk and mortality associated with many types of cancer including that of the breast. In mice, obesity increases both incidence of spontaneous tumors and burden of transplanted tumors. Our findings identify leptin, an adipose secreted cytokine, in promoting increased mammary tumor burden in obese mice and provide a link between this adipokine and cancer. Using a transplantable tumor that develops spontaneously in the murine mammary tumor virus-Wnt-1 transgenic mice, we show that tumors transplanted into obese leptin receptor (LepRb)-deficient (db/db) mice grow to eight times the volume of tumors transplanted into lean wild-type (WT) mice. However, tumor outgrowth and overall tumor burden is reduced in obese, leptin-deficient (ob/ob) mice. The residual tumors in ob/ob mice contain fewer undifferentiated tumor cells (keratin 6 immunopositive) compared with WT or db/db mice. Furthermore, tumors in ob/ob mice contain fewer cells expressing phosphorylated Akt, a growth promoting kinase activated by the LepRb, compared with WT and db/db mice. In vivo limiting dilution analysis of residual tumors from ob/ob mice indicated reduced tumor initiating activity suggesting fewer cancer stem cells (CSCs). The tumor cell populations reduced by leptin deficiency were identified by fluorescence-activated cell sorting and found to express LepRb. Finally, LepRb expressing tumor cells exhibit stem cell characteristics based on the ability to form tumorspheres in vitro and leptin promotes their survival. These studies provide critical new insight on the role of leptin in tumor growth and implicate LepRb as a CSC target.
The (mis)estimation of neighborhood effects: causal inference for a practicable social epidemiology.

The resurgence of interest in the effect of neighborhood contexts on health outcomes, motivated by advances in social epidemiology, multilevel theories and sophisticated statistical models, too often fails to confront the enormous methodological problems associated with causal inference. This paper employs the counterfactual causal framework to illuminate fundamental obstacles in the identification, explanation, and usefulness of multilevel neighborhood effect studies. We show that identifying useful independent neighborhood effect parameters, as currently conceptualized with observational data, to be impossible. Along with the development of a dependency-based methodology and theories of social interaction, randomized community trials are advocated as a superior research strategy, one that may help social epidemiology answer the causal questions necessary for remediating disparities and otherwise improving the public’s health.
Seismically imaged relict slab from the 55 Ma Siletzia accretion to the northwest United States

Teleseismic tomography images a large high-velocity “curtain” extending vertically beneath the ca. 50 Ma Challis magmatic trend to maximum depths of 230–600 km. We interpret this structure as subducted Farallon ocean lithosphere that stalled with the ca. 55 Ma accretion of the Siletzia microplate to North America within the Columbia Embayment, and we consider the regional tectonic implications. The abrupt switch ca. 53 Ma from Laramide thrusting and magmatic quiescence to extension and vigorous magmatism in the northwestern United States is evidence for foundering of the fl at-subducting Farallon slab. To account for the imaged curtain, foundering apparently occurred by rollback after Siletzia accretion terminated subduction within the Columbia Embayment. The magnitude of the high seismic velocity curtain is approximately that expected for 20–50 m.y. old ocean lithosphere that stalled in the upper mantle ca. 50 Ma. We suggest that the stalled slab became nearly neutrally buoyant as a result of removal of its basaltic crust, the melting of which likely contributed to the short-lived vigor of Challis magmatism. After Siletzia accretion, normal dip Cascadia subduction initiated west of Siletzia, evidenced by arc volcanism in Oregon and Washington beginning ca. 45–40 Ma, while continued quiescence of the Sierra Nevada arc suggests persistence of flsubduction to the south. Kinematically, this requires a tear in the subducted Farallon slab near the latitude of southern Oregon. We propose that north to south propagation of this torn slab edge propagated the ignimbrite fl are-up across what now is the northern Basin and Range and ended the Laramide orogeny.
PC BEEPOP, an ecotoxicological simulation model for honey bee populations

PC BEEPOP is a computer model that simulates honey bee (Apis mellifera L.) colony population dynamics. The model consists of a feedback system of interdependent elements, including colony condition (e.g., initial size, reproductive potential of the queen and forager longevity), environmental variability (e.g., weather) and contaminant exposures. It includes a mortality module (BEEKILL) and a chemical-toxicity data base and probit analysis program (BEETOX). PC BEEPOP is a modified version of an cxisting colony dynamics model, BEEPOP, and can be used as a tool for environmental risk assessments. Results of sensitivity analysis and simulations of various climatic and toxic scenarios are discussed and compared to observed changes in the size and composition of honey bee colony populations.
Dynamic registration correction in augmented-reality systems

This paper addresses the problem of correcting visual registration errors in video-based augmented-reality systems. Accurate visual registration between real and computer-generated objects in combined images is critically important for conveying the perception that both types of object occupy the same 3-dimensional (3D) space. To date, augmented-reality systems have concentrated on simply improving 3D coordinate system registration in order to improve apparent (image) registration error. This paper introduces the idea of dynamically measuring registration error in combined images (2D error) and using that information to correct 3D coordinate system registration error which in turn improves registration in the combined images. Registration can be made exact in every combined image if a small video delay can be tolerated. Our experimental augmented-reality system achieves improved image registration, stability, and error tolerance from tracking system drift and jitter over current augmented-reality systems. No additional tracking hardware or other devices are needed on the user's head-mounted display. Computer-generated objects can be "nailed" to real-world reference points in every image the user sees with an easily-implemented algorithm. Dynamic error correction as demonstrated here will likely be a key component of future augmented-reality systems.
Root and stem xylem embolism, stomatal conductance, and leaf turgor in Acer grandidentatum populations along a soil moisture gradient

The objective of this study was to determine how adjustment in stomatal conductance (g s) and turgor loss point (Ψtlp) between riparian (wet) and neighboring slope (dry) populations of Acer grandidentum Nutt. was associated with the susceptibility of root versus stem xylem to embolism. Over two summers of study (1993-1994), the slope site had substantially lower xylem pressures (Ψpx) and g s than the riparian site, particularly during the drought year of 1994. The Ψtlp was also lower at the slope (-2.9±0.1 MPa; all errors 95% confidence limits) than at riparian sites (-1.9±0.2 MPa); but it did not drop in response to the 1994 drought. Stem xylem did not differ in vulnerability to embolism between sites. Although slope-site stems lost a greater percentage of hydraulic conductance to embolism than riparian stems during the 1994 drought (46±11% versus 27±3%), they still maintained a safety margin of at least 1.7 MPa between midday Ψpx and the critical pressure triggering catastrophic xylem embolism (ΨpxCT). Root xylem was more susceptible to embolism than stem xylem, and there were significant differences between sites: riparian roots were completely cavitated at -1.75 MPa, compared with -2.75 MPa for slope roots. Vulnerability to embolism was related to pore sizes in intervessel pit membranes and bore no simple relationship to vessel diameter. Safety margins from ΨpxCT averaged less than 0.6 MPa in roots at both the riparian and slope sites. Minimal safety margins at the slope site during the drought of 1994 may have led to the almost complete closure of stomata (g s=9±2 versus 79±15 mmol m-2 s-1 at riparian site) and made any further osmotic adjustment of Ψtlp non-adaptive. Embolism in roots was at least partially reversed after fall rains. Although catastrophic embolism in roots may limit the minimum Ψ for gas exchange, partial (and reversible) root embolism may be adaptive in limiting water use as soil water is exhausted.