cssi/SciSciGPT-SciSciNet huggingface dataset:
Modeling of volatile contamination transport for surface operations of the Mars Science Laboratory

ABSTRACT Gas-phase contamination modeling for space systems typically looks at the free molecular flow regime, Knudsen number >> 1, wherein transport is characterized by collisionless motion of contaminant molecules and deposition proportional to grey- or black-body view factors. Such an approach, however, was not applicable to the contamination transport environment [to be] encountered by the NASA Mars Science Laboratory (MSL) during surface operations on the Red Planet. For MSL, we required an understanding of contaminant transport under the Mars-ambient conditions of an approximately 8 Torr CO 2 atmosphere in order to provide traceability between hardware outgassing limits and the allowable vapor-phase contaminant concentrations in the vicinity of atmospheric sampling sensors and deposition to prospective solid sample sites on the Martian surface. In setting outgassing requirements for the MSL surface system, an engineering upper-bound estimaterather than a precise result based on an all-inclusive simulation of the dynamic flow fieldof the local contamination density was needed. Here we describe a 3-D, low-speed computational fluid dynamics approach, including molecular diffusion, to determine mixing ratios of contaminants at the atmospheric sample inlets and solid sample inlet deposition rates. Turbulence enhances the effective diffusion, leading to the dilution of the volatile contaminants, which reduces contamination concentration at a distance far from the source in comparison to inviscid or laminar flow fields: Therefore, the approach employed here results in a conservative upper bound compared to one in which turbulence is explicitly addressed. Because contaminant transport in this environment (Peclet number in the range of 50-1000) is advection dominated, spatial contamination concentration is a strongly-peaked function of the wind direction. Results of sample calculations for expected Mar wind speeds ( u = 1-20 m/s) and several wind directions are presented.
Polymeric Materials for Theranostic Applications

Nanotechnology has continuously contributed to the fast development of diagnostic and therapeutic agents. Theranostic nanomedicine has encompassed the ongoing efforts on concurrent molecular imaging of biomarkers, delivery of therapeutic agents, and monitoring of therapy response. Among these formulations, polymer-based theranostic agents hold great promise for the construction of multifunctional agents for translational medicine. In this article, we reviewed the state-of-the-art polymeric nanoparticles, from preparation to application, as potential theranostic agents for diagnosis and therapy. We summarized several major polymer formulas, including polymeric conjugate complexes, nanospheres, micelles, and dendrimers for integrated molecular imaging and therapeutic applications.
Quel paradigme pour l'entrepreneuriat international ?

Resume L'entrepreneuriat international partage avec les autres sous-champs de l'entrepreneuriat la meme heterogeneite des sujets d'etude et des approches epistemologiques des chercheurs. Ces approches ne sont que rarement clarifiees ou analysees. Est-il possible a l'heure actuelle d'identifier clairement les principales positions epistemologiques et les courants paradigmatiques en entrepreneurial international? Le premier objectif de cette etude est d'apporter des elements de reponse a cette question en analysant l'heritage epistemologique de ce domaine d'etude ainsi que les courants paradigmatiques dans les deux champs dont est issu ce domaine, l'entrepreneuriat et la gestion internationale. Une meilleure connaissance des positions adoptees par les chercheurs peut contribuer a mieux definir l'entrepreneuriat international, et ce malgre la diversite des sujets d'etude. Le deuxieme objectif est d'etudier la question de la specialisation versus l'integration des paradigmes dans la recherche en entrepreneurial international. Doit-on, comme le proposent certains chercheurs, reduire le nombre et la diversite des sujets d'etude et des methodes employees de facon a favoriser l'emergence d'un paradigme unique, ou au contraire tenter d'integrer differents paradigmes? Abstract International entrepreneurship, like the other subfields of entrepreneurship, covers many different topics. Research in this area is based on different epistemological assumptions that are rarely clarified or analyzed. Is it possible to identify the main epistemological positions and the paradigmatic trends in international entrepreneurship? The first objective of this paper is to analyze the epistemological background of the area and to identify the main paradigmatic trends in the two fields from which international entrepreneurship is derived: entrepreneurship and international business. A better understanding of these positions and trends may make the area easier to define, even if the topics are varied. The second objective is to study the question of specialization versus integration of paradigms in this area. Should researchers reduce the number and diversity of topics and methods, so that a unique paradigm may emerge, or should they rather try to integrate different paradigms?
Culture change and integration: Thesis, antithesis, synthesis

(1963). Culture change and integration: Thesis, antithesis, synthesis. Anthropological Forum: Vol. 1, No. 1, pp. 122-134.
A mouse model for the study of in vivo mutational spectra: sequence specificity of ethylene oxide at the hprt locus.

We have developed an approach for determining mutational spectra in exon 3 of the hypoxanthine-guanine phosphoribosyl transferase (hprt) gene in splenic T-lymphocytes of B6C3F1 mice. Hprt- mutants from treated animals were isolated by culturing splenic T-cells in microtiter dishes containing medium supplemented with IL-2, concanavalin A, and 6-thioguanine. DNA was extracted from 6-thioguanine-resistant colonies and amplified by the polymerase chain reaction (PCR) using primers flanking the exon 3 region of hprt. Identification of samples containing mutant exon 3 sequences and purification of mutant DNA from contaminating wild-type hprt DNA was accomplished using denaturing gradient gel electrophoresis. Purified mutant sequences were then sequenced. This approach is being used to study the sequence specificity of ethylene oxide (ETO). 12-day-old mice were given single i.p. injections of 100 mg ETO/kg every other day or 30, 60, 90 or 120 mg ETO/kg daily for 5 days to achieve different cumulative doses of this compound. In mice exposed every other day, cumulative doses of 200, 600 and 900 mg ETO/kg produced average mutant frequencies of 15 +/- 12.8, 45 +/- 13.2, and 73 (70, 75) x 10(-6), respectively, 8 weeks after the first treatment. In mice exposed daily, cumulative doses of 150, 300, 450 and 600 mg ETO/kg produced average mutation frequencies of 4.2 +/- 10.4, 8.2 +/- 10.4, 11.1 +/- 1.0 and 15.5 +/- 10.7 x 10(-6), respectively, 20 weeks after the first treatment. The mutant fraction in control mice was less than 3 x 10(-6). 123 hprt- mutants from mice exposed to 600 or 900 mg ETO/kg were isolated and analyzed for mutations in exon 3. 18 were located in exon 3 (14.6%). DNA sequencing revealed that 11/18 mutations were base-pair substitutions at 8 different sites in exon 3. Four AT transversions, three AT transitions, two GC transversions, and two GC transitions were observed. Three of the substitutions (2 AT-->CG, 1 AT-->GC) occurred at one base (203) in a single animal. The remaining 7 mutations, isolated from 4 different animals, were the same +1 frameshift mutation in a run of 6 consecutive guanine bases (207-212) in exon 3. These results suggest the involvement of both modified guanine and adenine bases in ETO mutagenesis. The mouse T-cell cloning/sequencing assay for hprt described here represents a useful system for studying the molecular mechanism of chemically-induced mutation occurring in vivo at an endogenous gene.
Added challenges to gene therapy—immune responses in the setting of myeloablation

The genetic modification of hematopoietic stem cells (HSCs) holds promise as a therapeutic modality for a variety of disorders, including inherited metabolic disorders, malignancies, and HIV. The recent description of leukemia in children treated with HSC gene therapy[1][1] is a reminder that
Men grow old

Purpose – This sermon argues that artistry and understanding are the offspring of whole people: thoughtful, resolute, and passionate. It then considers some illiberal fashions in higher education that stifle passion. Design/methodology/approach – This is an opinion piece. Findings – Current threats to liberal education include metaphors demeaning to professors, incomprehensible or inconsequential learning objectives, and schemes that increase “intentionality” by limiting students' opportunities for exploration and discovery. Originality/value – This sermon makes vivid to educational leaders and would-be reformers some of the negative consequences of their actions and proposals.
R-modes of accreting hyperon stars as persistent sources of gravitational waves

The $r$-modes of accreting neutron stars could be a detectable source of persistent gravitational waves if the bulk viscosity of the stellar matter can prevent a thermal runaway. This is possible if exotic particles such as hyperons are present in the core of the star. We compute bulk viscous damping rates and critical frequencies for $r$-modes of neutron stars containing hyperons in the framework of relativistic mean field theory. We combine the results of several previous calculations of the microphysics, include for the first time the effect of rotation, and explore the effects of various parameters on the viability of persistent gravitational wave emission. We find that persistent emission is quite robust, although it is disfavored in stars below 1.3--1.5 ${M}_{\ensuremath{\bigodot}}$ depending on the equation of state. In some cases persistent emission is compatible with temperatures as low as ${10}^{7}\text{ }\text{ }\mathrm{K}$, observed in some accreting neutron stars in quiescence.
Tobacco smoke biomarkers and cancer risk among male smokers in the Shanghai cohort study.

Metabolites of tobacco smoke constituents can be quantified in urine and other body fluids providing a realistic measure of carcinogen and toxicant dose in a smoker. Many previous studies have demonstrated that these metabolites – referred to as biomarkers in this paper – are related to tobacco smoke exposure. The studies reviewed here were designed to answer another question: are these substances also biomarkers of cancer risk? Using a prospective study design comparing biomarker levels in cancer cases and controls, all of whom were smokers, the results demonstrate that several of these biomarkers – total cotinine, total 4-(methylnitrosamino)-1-(3-pyridyl)-1-butanol (NNAL), r-1-,t-2,3,c-4-tetrahydroxy-1,2,3,4-tetrahydrophenanthrene (PheT), and total N′-nitrosonornicotine (NNN) – are biomarkers of cancer risk. Therefore, these biomarkers have the potential to become part of a cancer risk prediction algorithm for smokers.
Multiagent System for Construction Dispute Resolution (MAS-COR)

This paper develops theoretical foundation and implements technologies for generation of legal arguments based on precedent construction disputes. First, the authors simulated the process of legal discourse in construction disputes using a formal logic algorithm that is based on adversarial precedent law. In this regard: (1) facts associated with construction change order cases were factorized into binary, dimensional, and abstract factors; (2) relevance of the developed factors was associated with the disputing parties; (3) logical predicates and rules were generated based on the said factors; (4) factors were logically analyzed into distinct classifications; and (5) an 11 stage logical induction algorithm was used to show similarities, differences, strengths, and weaknesses between current and precedent construction disputes. Second, the authors created a multiagent system for construction dispute resolution (MAS-COR) that automates the developed algorithm. In this connection: (1) an agent-based role model was developed to represent the developed algorithms; (2) an agent-based role model was built to represent the developed algorithm; and (3) system implementation was carried using object-oriented programming on NetBean's integrated development environment. Using 30 previously arbitrated construction disputes, testing and validation steps were rigorously applied to assess the developed formal logic algorithm as well as the associated created agents and their integration into the MAS-COR system through syntactical debugging using theorem proving, model checking, and system testing. The results of this validation process illustrated that the system was capable of deriving significant legal arguments that help save time and effort of construction claim and dispute professionals while preparing the defense for their respective positions.
Disinhibition in metacontrast masking of vernier acuity targets: Sustained channels inhibit transient channels

Abstract Foveal vernier resolution is impaired when a briefly presented target (T) is followed at varying stimulus onset asynchronies (SOA's) by a spatially adjacent set of metacontrast (M) bars. Impairment of resolution is optimal at intermediate SOA's (50–60 msec). When two flanking (F) bars are in turn placed adjacent to M and are presented either continuously throughout the T-M display sequence or else synchronously with T, a reduction of metacontrast effects at the previously optimal SOA′s occurs. Such a reduction does not occur when F is presented synchronously with M. In the framework of current neurophysiological interpretations of metacontrast. these results indicate that sustained channels inhibit transient channels.
A neural basis for category and modality specificity of semantic knowledge.

Prevalent theories hold that semantic memory is organized by sensorimotor modality (e.g., visual knowledge, motor knowledge). While some neuroimaging studies support this idea, it cannot account for the category specific (e.g., living things) knowledge impairments seen in some brain damaged patients that cut across modalities. In this article we test an alternative model of how damage to interactive, modality-specific neural regions might give rise to these categorical impairments. Functional MRI was used to examine a cortical area with a known modality-specific function during the retrieval of visual and non-visual knowledge about living and non-living things. The specific predictions of our model regarding the signal observed in this area were confirmed, supporting the notion that semantic memory is functionally segregated into anatomically discrete, but highly interactive, modality-specific regions.
Accelerated CD8 + T-cell memory and prime-boost response after dendritic-cell vaccination

Efficient boosting of memory T-cell numbers to protective levels generally requires a relatively long interval between immunizations. Decreasing this interval could be crucial in biodefense and cancer immunotherapy, in which rapid protective responses are essential. Here, we show that vaccination with peptide-coated dendritic cells (DCs) generated CD8+ T cells with the phenotype and function of memory cells within 4-6 d. These early memory CD8+ T cells underwent vigorous secondary expansion in response to a variety of booster immunizations, leading to elevated numbers of effector and memory T cells and enhanced protective immunity. Coinjection of CpG oligodeoxynucleotides, potent inducers of inflammation that did not alter the duration of DC antigen display, prevented the rapid generation of memory T cells in wild-type mice but not in mice lacking the interferon (IFN)-gamma receptor. These data show that DC vaccination stimulates a pathway of accelerated generation of memory T cells, and suggest that events of inflammation, including the action of IFN-gamma on the responding T cells, control the rate of development of memory CD8+ T cells.
AIBS Story: Genesis

In relation to the excellent article on "The AIBS Story: Genesis" here are some background remarks which you may find interesting. So far as I am-aware, discussions on the formation of such an organization began under the auspices of the Union of American Biological Societies of which I was recording secretary for some years. This was a loose and ineffectual union, and its officers realized that a more effective organization was needed to give biology the same voice and advantage as physics and chemistry with draft boards and in governmental and industrial laboratories. The UABS meetings, always poorly attended in my experience, were held in conjunction with the AAAS meetings at Christmas time, as I recall from my minutes, and one of the subjects on the agenda of these meetings was the formation of an effective organization of all biologists that could speak with a united voice. These discussions went on and on at several meetings without any concrete decisions, and I recall that after endless talk at a Boston meeting Anton Carlson, always a blunt and outspoken Swede, stood up and said "Vy de hdon't ve do sumting besides yust sitting on our damn aand yust talking." Besides such meetings of the UABS informal ones were held in Robert Chambers'
Regional mobility of economists

We find that nearly two- thirds of economists move to a different region of the U.S. or to a foreign country to accept their first job after receiving the Ph.D., that the South is the only net importer of economists among regions of the U.S., that the Midwest is the major net exporter, and that the proportion of graduates accepting foreign employment doubled during the 1980s. Gender and field of specialization do not affect mobility; however, doctorates from the top graduate schools and those accepting academic and government jobs are more likely to change regions than are graduates of lower ranked schools or those who are employed in the private sector.
Proper Choice of Final-State Wave Function for Dissociation and Its Effect on the Angular Distribution of Dissociation Fragments

The collisional dissociation of a homopolar diatomic molecule has been heretofore described in terms of a transition to the vibrational continuum of a single Born-Oppenheimer electronic state. This choice of final state, which is shown to be incorrect, yields dissociation-fragment angular distributions which are symmetric about an angle of 90 deg with respect to the beam. The proper final state yields angular distributions which need not possess this symmetry.
Compatibility of Rhenium in Garnet During Mantle Melting and Magma Genesis

Measurements of the partitioning of rhenium (Re) between garnet and silicate liquid from 1.5 to 2.0 gigapascals and 1250° to 1350°C show that Re is compatible in garnet. Oceanic island basalts (OIBs) have lower Re contents than mid-ocean ridge basalt, because garnet-bearing residues of deeper OIB melting will retain Re. Deep-mantle garnetite or eclogite may harbor the missing Re identified in crust-mantle mass balance calculations. Oceanic crust recycled into the upper mantle at subduction zones will retain high Re/Os (osmium) ratios and become enriched in radiogenic 187Os. Recycled eclogite in a mantle source should be easily traced using Re abundances and Os isotopes.
An assessment of the effectiveness of Full Option Science System training for third-through sixth-grade teachers

Twenty-nine third- and fourth-grade teachers and twenty-five fifth- and sixth-grade teachers from the Texarkana (Arkansas and Texas) area public schools were trained using the Full Option Science System (FOSS). Participants were given pretests and posttests to measure their: confidence toward teaching science, science content knowledge, attitude toward teaching science, and attitude toward science. Pretest and posttest results were compared using a paired t-test. The results revealed significant gains for both groups in teacher confidence toward teaching science, science content knowledge, and attitude toward teaching science. No significant increase in attitude toward science was detected in the third-and fourth-grade teachers. However, the fifth- and sixth-grade teachers did show a significant increase in their attitude toward science. Overall, it appears that Full Option Science System training is effective for third- through sixth-grade teachers.
Francisella-like endosymbionts of ticks.

Ticks affect human and animal health both directly by their blood feeding and indirectly by transmission of many disease-causing bacteria, such as Rickettsia, Ehrlichia, Borrelia, Coxiella, Cowdria, Anaplasma, Aegyptionella, and Tularemia, as well as many viruses (Piesman and Gage, 1996). In addition to these infectious agents, ticks harbor bacterial endosymbionts, such as Wolbachia persica, which was first isolated from the soft tick now classified as Argus arboreus (Suitor and Weiss, 1961).
Is there a probenecid sensitive transport system for monoamine catabolites at the level of the brain capillary plexus

Probenecid inhibits the transport of the small monocarboxylic acids lactate and propionate from blood to brain but does not affect the transport of 5HIAA or HVA. Neither lactate, 5HIAA, HVA, nor probenecid itself inhibits probenecid uptake into brain from blood and neither lactate nor 5HIAA itself inhibits 5HIAA uptake. These results indicate first that probenecid inhibits the lactate carrier but is itself not transported by that carrier and second that 5HIAA and probenecid are independently transported from blood to brain by a low affinity system, probably by diffusion. Preloading animals with both tryptophan and probenecid increased the apparent transport of lactate, probenecid and 5HIAA but not the transport of glucose. This indicates that the transport of 5HIAA, lactate and probenecid from brain to blood involves a common, saturable carrier. These two sets of data indicate that either the brain capillary transport system is asymmetric or that probenecid-inhibited transport of monoamine catabolites from brain occurs at sites other than the capillary transport system of the blood-brain barrier.
The effect of CNS metastases on the survival of patients with small cell cancer of the lung

The records of 227 patients with small cell lung cancer (SMCLC) treated between January 1974 and July 1978 in a series of randomized trials were reviewed to determine the influence of central nervous system (CNS) metastases on survival. Sixteen patients were excluded because of single agent chemotherapy (11), lack of CNS irradiation despite proven metastases (2), prior chemotherapy (2), and concomitant metastatic second primary (1). Of 211 evaluable patients, 100 presented with limited disease and 111 with extensive disease, 25 of whom had CNS metastases at presentation, 21 ("CNS-limited") as the only site of metastases. Treatment of limited patients consisted of chemotherapy and thoracic radiation, while chemotherapy alone was used for extensive patients. No prophylactic brain irradiation was used, but CNS radiation was given to almost all patients when CNS metastases developed. Median survivals were: limited, 13.8 months; CNS-limited, 15.1 months; and extensive 8.6 months (P less than 0.0001). There was no significant difference in the survival experience of limited and CNS-limited patients, although none of the CNS-limited patients experienced long-term remissions. Thirty-five of the limited patients and 21 of the extensive patients subsequently developed CNS metastases. Their median survivals following CNS metastases were 3.7 months and 1.6 months, respectively. In conclusion, CNS metastases as the sole site of metastatic disease at diagnosis of SMCLC is not necessarily a bad prognostic sign, while the subsequent development of CNS metastases may be.
Cytoskeletal structure of diseased and normal hemocytes of Mya arenaria

Abstract Molluscan hemocytes function in the overall defense of the animal by phagocytosing foreign material. When this phagocytic ability is impaired the animal becomes increasingly vulnerable to physiological disruption by foreign agents. As in other bivalves, hemocytes of Mya arenaria have been shown to phagocytose a variety of foreign materials and to possess the hydrolytic enzymes necessary to degrade incorporate substances. However, hemocytes from diseased animals demonstrate almost no phagocytic capabilities. When allowed to settle on glass, diseased (abnormal) hemocytes remain rounded and generally unattached, with only a few short membrane extensions; they do not clump. Whole cell transmission electron microscopy preparations demonstrate an altered cytoskeletal architecture in diseased hemocytes as compared to that found in nondiseased (normal) cells. Hemocyte preparations incubated in rhodamine-conjugated phalloidin and observed with fluorescence microscopy show altered actin filament patterns in diseased hemocytes. The disrupted cytoskeletal structure observed in diseased hemocytes likely accounts for the inability of cells to clump, adhere to glass, and phagocytose foreign materials.
Otolaryngologic manifestations of Multiple Pterygium Syndrome

Escobar Syndrome, or Multiple Pterygium Syndrome (MPS), is a rare syndrome with multiple congenital anomalies involving the head and neck area and limbs. Affected individuals have multiple pterygia, camptodactyly and/or syndactyly as the main features of this syndrome. Patients with MPS have a characteristic facies, including ptosis, antimongoloid slant of the palpebral fissures, hypertelorism, micrognathia, neck pterygia, and a sad flat, emotionless look to the face. We present a case of MPS recently treated at our institution for the purpose of further describing the clinical features of this syndrome, emphasizing the otolaryngologic manifestations. Increased awareness of MPS will facilitate appropriate management of this syndrome.
Macromolecular organometallic catalysis: II. Epoxidation using a polymeric quaternary ammonium hydrogen tungstate catalyst☆

Abstract The concept of heterogeneous catalysis by Organometallic polymers is presented. These macromolecules are insoluble and contain as an integral part moieties normally recognized as soluble catalysts. The utility of such systems is discussed and demonstrated by a comparison of the efficiency of an insoluble and soluble tungsten catalyst in the epoxidation of maleic acid with hydrogen peroxide. A pseudohomogeneous rate equation is proposed for this new type of catalysis and the reaction rate constants and the kinetics are established in terms of a diffusion-controlled catalystlined pore model.
Photodissociation of M+(benzene)x complexes (M = Ti, V, Ni) at 355 nm

Abstract Transition metal cation–benzene complexes of the form M + (C 6 H 6 ) 1–7 (M = Ti, V, Ni) are produced in a laser vaporization pulsed nozzle cluster source. The clusters are mass selected and photodissociated using the third harmonic of a Nd:YAG laser (355 nm). Ti + (C 6 H 6 ) fragments via ligand decomposition to produce Ti + C 4 H 2 , Ti + C 2 H 2 , and Ti + . V + (C 6 H 6 ) fragments by ligand elimination of neutral benzene to give V + as the primary fragment. Ni + (C 6 H 6 ) fragments via both ligand elimination and a photoinduced charge transfer pathway to give benzene cation. Complexes with two benzene ligands fragment by the loss of a single neutral benzene to leave M + (C 6 H 6 ) as the fragment. Clusters with more than two benzenes fragment directly down to M + (C 6 H 6 ) 2 with a small amount of M + (C 6 H 6 ) for M = Ti and Ni. This indicates that a stable sandwich core is established at M + (C 6 H 6 ) 2 that is solvated by subsequent benzenes. There is no evidence for three-fold coordination in any of these complexes.
Copolymerization kinetics of styrene/vinyl-ester systms: Low temperature reactions

Vinyl-ester (VE), synthesized by the addition reaction of methacrylic acid and diglycidyl ether of bis-phenol A (DGEBA) epoxy, and styrene react via bulk free radical chain growth copolymerization to form a crosslinked network polymer. Vital clues regarding the development and the structure of the network were obtained from the study of copolymerization kinetics of styrene/VE systems. Fourier transform infrared (FTIR) spectroscopy was used to obtain the individual fractional conversion rates of both the monomers. The conversion versus time data for both styrene and VE was fit to an autocatalytic kinetic model. The autocatalytic model was found to adequately replicate the kinetic data over the entire life of cure. In this investigation, the effects of styrene concentration, temperature, catalyst concentration, and initiator concentration on cure kinetics of styrene/VE systems were studied. The conversion profiles of both styrene and VE were used to obtain the reactivity ratios of the two monomers. The reactivity ratios were evaluated to be close to zero, suggesting that initially alternating copolymerization is favored over homopolymerization. The cure behavior of vinyl-ester resins is affected not only by the chemical reactivity of the monomers toward the free radicals, but also by diffusion effects, phase separation, and microgel formation. The interplay of these factors controls the kinetics of cure, thereby affecting the physical and chemical properties of the resulting polymer.
Population genetic structure of the toad Bufo woodhousii: an empirical assessment of the effects of haplotype extinction on nested cladistic analysis

Nested cladistic analysis (NCA) is increasingly being used to infer historical population-level processes, including population fragmentation, range expansion and long-distance colonization. However, the effects on interpretation of NCA inferences of stochastic extinction of haplotypes due to genetic drift (lineage sorting), or of haplotype loss via localized biotic or climatic influences, have not been thoroughly explored. We provide empirical evidence suggesting that NCA may misinterpret population history when haplotypes or haplotype groups from one clade are replaced by those of another clade. We do so by using NCA to analyse mitochondrial sequences from the toad Bufo woodhousii from 45 locations spanning the Great Plains and southwestern USA. Portions of this region were glaciated and/or desertified in the late Pleistocene and early Holocene, and hence uninhabitable for plains-dwelling organisms. Although NCA inferences of isolation-by-distance and gradual range expansion in B. woodhousii are compatible with expectations based on climatic data and toad biology, NCA also detected several instances of long-distance movement. Such movement seems unlikely, given the low vagility of this species. We conclude that inferences of long-distance colonization likely result from extinction of haplotypes in intervening areas. We suggest using additional methods to look for congruent inferences, and amending the NCA inference key, to help avoid misinterpretations resulting from haplotype extinction.
A brief history of Alzheimer's disease gene discovery

The rich and colorful history of gene discovery in Alzheimer's disease (AD) over the past three decades is as complex and heterogeneous as the disease, itself. Twin and family studies indicate that genetic factors are estimated to play a role in at least 80% of AD cases. The inheritance of AD exhibits a dichotomous pattern. On one hand, rare mutations inAPP, PSEN1, and PSEN2 are fully penetrant for early-onset ( 95%) late-onset AD. These four genes account for 30-50% of the inheritability of AD. Genome-wide association studies have recently led to the identification of additional highly confirmed AD candidate genes. Here, I review the past, present, and future of attempts to elucidate the complex and heterogeneous genetic underpinnings of AD along with some of the unique events that made these discoveries possible.
Boundary walking test: an accelerated scan method for greater system reliability

Printed circuit board (PCB) interconnect test and reliability is addressed. The boundary scan test methodology proposed in the IEEE standard 1149.1 is reviewed, and its limitation is critically analyzed. Based on this, a technique is proposed to automate the interconnect wiring test, which is performed as part of the power-on self-test. Essential to the idea is the use of a walking sequence for test stimulus, and response compression by the multiple input signature registers (MISRs). The salient feature is its simplicity of operation. Unlike the existing boundary-scan methodology, interconnects are tested via on-site test generation; faults are detected by comparing the content of the MISR with the anticipated response. Formal analysis shows that the technique has a high test-coverage for the most common defects. As a result, PCB interconnect testing can be accomplished as part of the power-on self-test without external test fixtures. >
Femtosecond-laser-based synthesis of ultrastable microwave signals from optical frequency references.

We use femtosecond laser frequency combs to convert optical frequency references to the microwave domain, where we demonstrate the synthesis of 10-GHz signals having a fractional frequency instability of ??3.5×10?15 at a 1-s averaging time, limited by the optical reference. The residual instability and phase noise of the femtosecond-laser-based frequency synthesizers are 6.5×10?16 at 1s and ?98dBc?Hz at a 1-Hz offset from the 10-GHz carrier, respectively. The timing jitter of the microwave signals is 3.3fs.
Fear of walking outdoors. A multilevel ecologic analysis of crime and disorder.

Background Although a number of studies have tested ecologic models that postulate relationships among social networks, the built environment, and active living, few neighborhood-based studies have considered the role of crime and violence. This study investigates the degree to which individual-level demographic characteristics and neighborhood-level physical and social characteristics are associated with increased fear of crime. Methods Data were analyzed in 2007 from a 2005 survey of 901 randomly selected individuals living in 55 neighborhoods in Washington DC. Multilevel ordered logit regression was used to examine associations between individual-level and neighborhood-level characteristics and how often fear of crime prevents a respondent from walking outdoors. Results Age and female gender were associated with an increase in fear; the percentage of a resident's life spent in the same neighborhood was associated with a decrease in fear. Results of cross-level interactions showed that at the neighborhood level, women were more fearful than men in neighborhoods without violence, but that the difference in fear between men and women shrinks as neighborhood violence increases. Collective efficacy was found to increase fear among black respondents and had no effect on fear among nonblack respondents. Conclusions If the study of neighborhoods and active living is to progress and contribute to both etiologic understanding and policy formation, it is essential that theoretical and empirical models consider the impact of violence and fear on walking. Efforts to increase active living in urban neighborhoods that do not account for the impact of crime and fear may fall short of their intended outcomes.
Zero-Order Release Kinetics from a Self-Correcting Floatable Asymmetric Configuration Drug Delivery System

A new approach based on the three-layer matrix technology to control drug release for oral administration is presented. Polyethylene oxide polymers of various molecular weight together with theophylline as drug model and other excipients have been directly compressed into a three-layer asymmetric floatable system. The core layer contains the active drug while external layers with different thickness, composition, and erosion rates are designed to delay the hydration of the middle layer, restrict the early drug diffusion only through cylindrical side surfaces of the tablet, and provide controlled drug release. Results show that during a 16 h dissolution study drug is completely released following the zero-order kinetics with no burst effect. The release rate remains around 0.1 mg min–1 throughout the dissolution study. The release kinetics is independent of changes in pH and compression force but dependent on layer thickness and formulation components. It appears that the operating release mechanism is based on the existence of a balance between the velocities of advancing glassy/rubbery front and erosion at the swollen polymer/dissolution front.
Using the international classification of functioning, disability and health to expand understanding of paralysis in the United States through improved surveillance.

Background Surveillance on paralysis prevalence has been conceptually and methodologically challenging. Numerous methods have been used to approximate population-level paralysis prevalence estimates leading to widely divergent prevalence estimates.
Likelihood ratios in the diagnosis of renal artery stenosis by magnetic resonance angiography compared with renal angiography.

Background Renal angiography (RA) is considered to be the gold standard for the diagnosis of renal artery stenosis (RAS). However, it is invasive and potentially harmful; hence there is a need for an optimal noninvasive test. Magnetic resonance angiography (MRA) is currently accepted as the optimal noninvasive test by many. However, its major drawback is its inability to grade quantitatively the degree of stenosis. In this study, likelihood ratios (LR) were used to compare the diagnostic accuracy of MRA with that of RA. Methods To test the hypothesis that semiquantitatively graded MRA would correlate with RA, a retrospective analysis was performed to determine the LR of MRA to diagnose RAS compared with RA. It was believed that LR ≥10.0 or ≤0.1 might generate conclusive changes from pretest to post-test probabilities. In this study a total of 94 renal arteries from 48 patients were analyzed for RAS by MRA and RA. Stenoses were graded by MRA as mild ( 75%); and by RA as <75% or ≥75% stenosis. Results The LR was 0.13 (95% CI = 0.09 to 0.19) for mild stenosis, 0.11 (95% CI = 0.08 to 0.15) for moderate stenosis, and 2.2 (95% CI = 1.9 to 3.1) for severe stenosis by MRA. Conclusions Nonsevere stenosis can be sufficiently diagnosed by MRA and may not warrant RA. However, it may be insufficiently precise to establish severe RAS based on LR results. Therefore, for severe RAS by MRA, the decision to obtain RA can be made with the help of post-test probability, which is determined using pretest probability and LR.
Comparison of musculoskeletal anatomic relationships, determined by magnetic resonance imaging, in postpubertal female patients with and without classic bladder exstrophy

What's known on the subject? and What does the study add? Several studies in the paediatric literature have characterized the pelvic musculoskeletal anatomy of infants and children with bladder exstrophy using MRI and three-dimensional CT. The pelvic floor anatomy of female patients with bladder exstrophy who have undergone somatic growth and puberty is less well described. This study uses MRI to characterize comprehensively the pelvic anatomy of postpubertal females with classic bladder exstrophy by measuring 15 pelvic floor variables previously described in younger children with bladder exstrophy. Objective To characterize pelvic musculoskeletal anatomy in postpubertal females with classic bladder exstrophy, and to compare this with females without bladder exstrophy. Patients and Methods The authors reviewed the medical records of all females in our institutional review board-approved bladder exstrophy database of 1078 patients and identified those with classic bladder exstrophy who underwent pelvic magnetic resonance imaging (MRI) after the age of 12 years. Indications for MRI included haematuria, adnexal lesion, perineal fistula, non-pelvic cancer staging, abdominal wall hernia and vaginal stenosis. Age- and race-matched female patients without exstrophy who underwent MRI evaluation for similar indications were included for comparison. The MRI protocol included axial, sagittal and coronal T1- and/or T2-weighted imaging. Results The study included 30 patients with a median (range) age of 22.5 (12–55) years at time of MRI. Ten patients had bladder exstrophy while 20 control patients did not. A smaller percentage of levator ani was located in the anterior compartment of the pelvis in patients with bladder exstrophy compared with controls. The iliac wing angle, puborectalis angle, ileococcygeous angle, levator ani width, symphyseal diastasis, erectile body diastasis, posterior bladder neck distance and posterior anal distance was greater in patients with bladder exstrophy than in those without. The ischial angle and obturator internus angle were narrower in patients with bladder exstrophy than in those without, and there was no significant difference between levator ani surface area, sacral anal angle, sacral bladder neck angle and bladder neck erectile body distance between the two patient groups. Conclusions In postpubertal females with bladder exstrophy, significant deviations from normal pelvimetry exist, including posterior location of the majority of the levator ani muscle, a wider ileococcygeous angle and a wider symphyseal diastasis. These differences are similar to those described in previous comparisons of younger children with bladder exstrophy and control children.
Design and analysis of a secure two-phase locking protocol

In addition to maintaining consistency of the database, secure concurrency control algorithms must be free from covert channels arising due to data conflicts between transactions. The existing secure concurrency control approaches are unfair to transactions at higher access classes. A secure two-phase locking protocol is presented, which is correct and free from covert channels. The protocol uses three different types of locks to support non-interference property and to provide reasonably fair execution of all transactions, regardless of their access class. The results of a performance evaluation of the protocol are provided, comparing it with secure optimistic concurrency control and secure multiversion timestamp ordering. >
Temperamental and Joint Attentional Predictors of Language Development

Individual differences in child temperament have been associated with individual differences in language development. Similarly, relationships have been reported between early nonverbal social communication (joint attention) and both temperament and language. The present study examined whether individual differences in joint attention might mediate temperament-language relationships. Temperament, language, and joint attention were assessed in 51 21-month-olds. Results indicated an inverse relationship between aspects of temperamental difficulty, including low executive control and high negative affect, and language development. Temperamental aspects of negative affect were also inversely predictive of joint attention. However, the utility of a model in which joint attention mediates the relationship between temperament and language during the second year was not supported.
Correlation Between Morphology and Function in Isolated Islets of the Zucker Rat

Obesity in the Zucker rat is accompanied by hyperlipemia, hyperinsulinism, insulin resistance, pancreatic hyperplasia, and islet hypertrophy. This study correlates the morphologic heterogeneity of isolated pancreatic islets with secretion of insulin and glucagon in the perifusion system. Islet size was arbitrarily defined as large (greater than 0.45 mm) or small (smaller than 0.12 mm). Protein content and volume (V = 4/3pir3) were calculated for groups and individual islets, respectively. Islets from obese rats secreted more insulin in response to glucose and aminophylline than islets from lean rats (peak 7.8 +/- 2.4 vs. 1.5 +/- 0.37 microU/islet/min, P less than 0.005). Insulin release was related directly to islet size and protein content. Small islets from lean and obese animals produced less insulin per islet than large islets (P less than 0.005). In terms of islet volume, however, large islets were inefficient insulin releasers as compared to small islets (P less than 0.005). Stimulation with Br-cAMP released glucagon from islets of lean but not from large islets of obese animals (peak 11 +/- 3.3 vs. 4.1 +/- 0.3 pg/microgram protein per minute, P less than 0.05). Arginine produced the same effect on glucagon release (P less than 0.05) as stimulation with Br-cAMP. The observed increased insulin release rates and the blunted glucagon response are related to islet size in the pancreas of the Zucker rat.
Examining the Impact of Moral Imagination on Organizational Decision Making

Emerging research suggests that an organization’s ability to sustain a competitive advantage is increasingly linked to its successful pursuit of a business strategy that generates mutual benefit wh...
Observer-rated rapport in interactions between medical students and standardized patients.

Objective: To measure rapport between medical students and standardized patients using observer ratings; to relate these ratings to students’ emotional awareness and to behavior within the medical interaction; and to assess the relative validity of using excerpts of different lengths for the measurement of rapport. Methods: Third-year medical students (N = 141) were videotaped during a 15-min interaction with a standardized patient, and rapport as well as other communication variables were measured using trained coders. Rapport was measured with good interrater reliability by trained coders who viewed three 1-min excerpts. Emotional awareness was measured by a test of recognizing facial expressions of emotion, self-ratings of emotional self-awareness, and peer ratings of interpersonal sensitivity. Finally, participants who viewed the videotapes while imagining themselves to be the patient (analogue patients) provided impressions of the students, including satisfaction. Results: Rapport based on all three minutes was positively correlated with accuracy in decoding facial expressions of emotion, self-reported attention to one’s own emotions, peer ratings of sensitivity, communication behaviors of the medical student and standardized patient, and analogue patients’ positive impressions and satisfaction. Rapport based on just the first minute of the interaction was significantly related to many of these variables. Conclusion: Rating short excerpts of behavior is a valid and efficient methodology for capturing the concept of rapport. Practice implications: Clinicians, researchers, and educators should focus on rapport building, even very early in the medical visit.
A Set Associative Cache Model with Energy Saving

This paper proposes a method to save energy in set associative cache. The method gathers the time of access of each memory address by profiling. Additional information about next access to a way is maintained in the cache ways. All the ways of the cache are put in either disable mode or low energy mode as supported by the cache. At each time unit, the cache ways are searched enabling the way that is going to be accessed next. If no way is going to be accessed in the next time unit, the generated address is placed respecting the replacement algorithm in the cache using the address mapping function. During this mapping all the ways of the mapped set are enabled as in a traditional set associative cache. The model was simulated on SPEC2 000 benchmarks with average energy savings of 19% and performance degradation of about 10%.