cssi/SciSciGPT-SciSciNet huggingface dataset:
Large area visible arrays: performance of hybrid and monolithic alternatives

CMOS-based imaging system-on-chip (i-SoC) technology is successfully producing large monolithic and hybrid FPAs that are superior in many respects to competing CCD-based imaging sensors. The hybrid approach produces visible 2048 by 2048 FPAs with <6 e- read noise and quantum efficiency above 80% from 400 nm to 920 nm; 4096 by 4096 mosaics are now being developed. The monolithic approach produces visible 12-bit imaging system-on-chips such as a 1936 by 1088 with higher quantum efficiency than mainstream CCDs, <25 e- read noise, <0.02% fixed pattern noise, automatic identification and replacement of defective pixels, black-level clamping, total power dissipation of only 180 mW, and various programmable features. Several successors having ≥12 Mpixels are in development. In both cases low-light-level performance is boosted by coupling the sensors to image intensifiers.
Woltjer's variational principle, II: The case of unbounded domains

Abstract We show for a wide class of unbounded domains, that minimizing the magnetic energy subject to prescribed helicity or relative helicity, does not lead to non-trivial force-free fields. Instead, we show by an explicit construction that all minimizing sequences satisfying the helicity constraint, converge to a vacuum field.
Student Perceived Value of Anatomy Pedagogy, Part I: Prosection or Dissection?

A series of three annual surveys of David Geffen School of Medicine (DGSOM) at UCLA students and UCR/UCLA Thomas Haider Program in Biomedical Sciences students were administered from 2010 to 2012 to ascertain student perceptions of which anatomy pedagogy—prosection or dissection—was most valuable to them during the first year of preclinical medical education and for the entire medical school experience in general. Students were asked, “What value does gross anatomy education have in preclinical medical education?” We further asked the students who participated in both prosection and dissection pedagogies, “Would you have preferred an anatomy curriculum like the Summer Anatomy Dissection during your first year in medical school instead of prosection?” All students who responded to the survey viewed anatomy as a highly valued part of the medical curriculum, specifically referring to four major themes: Anatomy is (1) the basis for medical understanding, (2) part of the overall medical school experience, (3) a bridge to understanding pathology and physiology, and (4) the foundation for clinical skills. Students who participated in both prosection and dissection pedagogies surprisingly and overwhelmingly advocated for a prosection curriculum for the first year of medical school, not a dissection curriculum. Time efficiency was the dominant theme in survey responses from students who learned anatomy through prosection and then dissection. Students, regardless of whether interested in surgery/radiology or not, appreciated both pedagogies but commented that prosection was sufficient for learning basic anatomy, while dissection was a necessary experience in preparation for the anatomical medical specialties. This suggests that anatomy instruction should be integrated into the clinical years of medical education.
Oxidation of biphenyl in supercritical water: Reaction kinetics, key pathways, and main products

We have shown that biphenyl, the central structural block in polychlorinated biphenyl (PCB) molecules, is also a key component of PCB reaction networks in supercritical water (SCW). This study provides information on biphenyl thermolysis (SCWT) and oxidation (SCWO) in SCW, proves the high chemical stability of biphenyl to SCWT/SCWO conditions, and exposes the complexity of the opening-ring reactions involved in overall PCB reaction networks. The decomposition reactions of biphenyl are investigated at 25 MPa and 673-823 K in SCW in the presence of methanol, with and without oxygen (from H 2 O 2 /H 2 O solutions). The experiments with biphenyl, delivered to a tubular reactor both as solutions in methanol (2-6 g/L and 5 wt %) and neat (melted) reactant, are conducted isothermally at plug flow conditions. GC-FID/ TCD/MSD chromatographic methods are employed for product analysis. Global conversions for biphenyl disappearance under SCWO conditions vary from 3% (673 K and 3.8 s) to 97% (823 K and 14.2 s) when delivered at 2-6 g/L and follow overall second-order kinetics with Arrhenius parameters A = 10 24±0.3 (mol/L) -1 s -1 and E a = 294 ± 5 kJ/mol. The global kinetic model developed from these data is also valid for the SCWO of biphenyl/MeOH at 5 wt %, but it fails in the case of neat biphenyl. These findings suggest an important contribution of methanol in the reaction mechanisms, products, and pathways. The main primary reaction products are all three hydroxybiphenyl isomers. However, more than 50 other minor reaction intermediates (yields less than a few tenths of a percent) have been identified under different SCWO conditions. No significant reactions are observed under SCWT conditions.
Hartree Calculations for the Ground State of Solid He and other Noble Gas Crystals

A single-particle model in which the wave functions are spherically symmetric about each lattice site was used to calculate the ground-state energy ${E}_{0}$ of solid He. The self-consistent Hartree equations (which yielded the best such wave functions) were solved numerically to an accuracy of better than 1%. The results were worse than could have been expected a priori: At the observed densities, the calculated values of ${E}_{0}$ were approximately +34 and +14 cal/mole for ${\mathrm{He}}^{3}$ and ${\mathrm{He}}^{4}$, respectively, as compared with experimental values of -4.5 and -12 cal/mole. Previous calculations are discussed in the light of our results. In addition, we calculated ${E}_{0}$ for the crystals of the other noble gas elements. The results for Ar, Kr, and Xe are within experimental error whereas ${\mathrm{E}}_{0}$ for Ne is definitely outside this error (being about 5% higher than experiment).
Showered calcific emboli to the brain, the 'salted pretzel'sign, originating from the ipsilateral internal carotid artery causing acute cerebral infarction

Background and Purpose— Unenhanced head CT has become the first line imaging study in the evaluation of suspected acute cerebral ischemia. It is important to identify subtle findings of acute ischemia on this exam to direct appropriate patient management. Summary of Case— We report the first case of multiple pial surface distal internal carotid artery territory calcified emboli causing multifocal cerebral infarctions, likely from a carotid bifurcation source. Conclusions— Visualization of multiple pial surface calcifications on unenhanced head CT, the ‘salted pretzel sign’, should raise suspicion for acute infarction from showered calcific emboli.
Secondary Patterning of UV Imprint Features by Photolithography

An acid-cleavable cross-linker (2,5-dimethyl-2,5-hexanediol dimethacrylate or DHDMA) was prepared and patterned with UV imprint lithography (UV-IL) to create cross-linked films that could be second...
Just-in-time databases and the World-Wide Web

1. ABSTRACT It is not always possible or practical to store very large data sets in a relational database. For example, in a rapidly changing large-scale environment with distributed control, such as the World-Wide Web, a strict relational approach is not feasible. Nevertheless, it is desirable for a user to be able to make SQL queries on the entire data set, because SQL is well known, supported, and understood. We introduce “just-in-time databases”, which allow the user to query the entire data set as though it were in a relational database. The underlying engine brings data into the relational database only when it is required by user queries. We describe how “just-in-time databases” are implemented, using the WorldWide Web as an example. 1.1
Transport of messenger RNA from the nucleus to the cytoplasm

All movement of molecules and macromolecules between the cytoplasm and the nucleus takes place through nuclear pore complexes (NPCs), very large macromolecular complexes that are the only channels connecting these compartments. mRNA export is mediated by multiple, highly conserved protein factors that couple steps of nuclear pre-mRNA biogenesis to mRNA transport. Mature messenger ribonucleoproteins (mRNPs) diffuse from sites of transcription to NPCs, although some active genes are positioned at the nuclear periphery where they interact physically with components of NPCs. As properly processed mRNPs translocate through the pore, certain mRNP proteins are removed, probably through the enzymatic action of the DEAD-box helicase Dbp5, which binds to Nup159 and Gle1, components of the cytoplasmic filaments of the NPC. Gle1 and the phosphoinositide IP6 activate Dbp5's ATPase activity in vitro and this could provide critical spatial regulation of Dbp5 activity in vivo.
International Rice Genome Sequencing Project: the effort to completely sequence the rice genome

The International Rice Genome Sequencing Project (IRGSP) involves researchers from ten countries who are working to completely and accurately sequence the rice genome within a short period. Sequencing uses a map-based clone-by-clone shotgun strategy; shared bacterial artificial chromosome/P1-derived artificial chromosome libraries have been constructed from Oryza sativa ssp. japonica variety 'Nipponbare'. End-sequencing, fingerprinting and marker-aided PCR screening are being used to make sequence-ready contigs. Annotated sequences are immediately released for public use and are made available with supplemental information at each IRGSP member's website. The IRGSP works to promote the development of rice and cereal genomics in addition to producing genome sequence data.
Recovering nonlinearly distributed knowledge: Computing discourse structure in factual reports

This paper presents a new type of nonlinear discourse structure found to be very common in free English texts. This structure reflects nonlinear presentation of the information and knowledge conveyed by the texts. It is argued that such nonlinearity is representationally and informationally advantageous because it allows one to create smaller, more compact texts. The paper presents a heuristics-based, relatively domain-independent algorithm for computing this new text structure. The paper discusses good quantitative and qualitative performance of the algorithm, and presents the results of the extensive tests on a large volume of free English texts.
Asymmetric B Cell Division in the Germinal Center Reaction

Lifelong antibody responses to vaccination require reorganization of lymphoid tissue and dynamic intercellular communication called the germinal center reaction. B lymphocytes undergo cellular polarization during antigen stimulation, acquisition, and presentation, which are critical steps for initiating humoral immunity. Here, we show that germinal center B lymphocytes asymmetrically segregate the transcriptional regulator Bcl6, the receptor for interleukin-21, and the ancestral polarity protein atypical protein kinase C to one side of the plane of division, generating unequal inheritance of fate-altering molecules by daughter cells. Germinal center B lymphocytes from mice with a defect in leukocyte adhesion fail to divide asymmetrically. These results suggest that motile cells lacking constitutive attachment can receive provisional polarity cues from the microenvironment to generate daughter cell diversity and self-renewal.
Resolution in elastography

The limits of the spatial resolution in elastography were investigated using a controlled simulation study. The results show that the axial resolution in elastography is limited by the bandwidth of the ultrasound system used to acquire the data and the lateral resolution is determined by the beamwidth of the ultrasound transducer.
Post-translational Processing of Membrane-associated neu Differentiation Factor Proisoforms Expressed in Mammalian Cells (∗)

Expression vectors constructed from human and rat pro-neu differentiation factor (NDF) cDNAs were transfected in Chinese hamster ovary cells for expression of recombinant NDF molecules. Soluble NDF forms were released into culture medium after post-translational processing of the membrane-bound pro-NDF forms. Different human and rat NDF isoforms, after being purified from the culture medium, were subjected to structural and biochemical characterizations. The isolated human and rat NDF isoforms have been proteolytically processed at a specific site at the N terminus, which is different from that observed for the processing of rat or human NDF molecule prepared from natural origins. The processing of each recombinant NDF isoform at its C terminus was heterogeneous but consistently occurred at nearby peptide bonds. Specific N- and C-terminal processing by Chinese hamster ovary cells has resulted in the production of two types (α and β) of recombinant NDFs containing 222-225 amino acid residues. Both human and rat NDF molecules are heavily glycosylated at two of the three potential Asn-linked glycosylation sites and contain O-linked sugars at 11 of the Thr/Ser sites. Glycosylation occurs at a short, Ser/Thr-rich spacer region that connects the N-terminal immunoglobulin homology unit to the epidermal growth factor domain. Cellular phosphorylation assay indicated that these secreted forms contain similar biological activity in receptor tyrosine autophosphorylation of mammary tumor cells.
PolyBot: a modular reconfigurable robot

Modular, self-reconfigurable robots show the promise of great versatility, robustness and low cost. The paper presents examples and issues in realizing those promises. PolyBot is a modular, self-reconfigurable system that is being used to explore the hardware reality of a robot with a large number of interchangeable modules. PolyBot has demonstrated the versatility promise, by implementing locomotion over a variety of terrain and manipulation versatility with a variety of objects. PolyBot is the first robot to demonstrate sequentially two topologically distinct locomotion modes by self-reconfiguration. PolyBot has raised issues regarding software scalability and hardware dependency and as the design evolves the issues of low cost and robustness will be resolved while exploring the potential of modular, self-reconfigurable robots.
Goal-directed decision making in prefrontal cortex: a computational framework

Research in animal learning and behavioral neuroscience has distinguished between two forms of action control: a habit-based form, which relies on stored action values, and a goal-directed form, which forecasts and compares action outcomes based on a model of the environment. While habit-based control has been the subject of extensive computational research, the computational principles underlying goal-directed control in animals have so far received less attention. In the present paper, we advance a computational framework for goal-directed control in animals and humans. We take three empirically motivated points as founding premises: (1) Neurons in dorsolateral prefrontal cortex represent action policies, (2) Neurons in orbitofrontal cortex represent rewards, and (3) Neural computation, across domains, can be appropriately understood as performing structured probabilistic inference. On a purely computational level, the resulting account relates closely to previous work using Bayesian inference to solve Markov decision problems, but extends this work by introducing a new algorithm, which provably converges on optimal plans. On a cognitive and neuroscientific level, the theory provides a unifying framework for several different forms of goal-directed action selection, placing emphasis on a novel form, within which orbitofrontal reward representations directly drive policy selection.
Brief report: Chromosomal analysis of perinatal death in Macaca mulatta and Macaca radiata.

Peripheral blood samples from 53 macaque perinatal deaths at the California Primate Research Center (CPRC) were cultured to produce chromosomes for analysis. Karyotypes were constructed for 26 successful cultures and revealed no apparent chromosomal anomalies. A genetic screening program at primate breeding facilities is important for estimating the frequency of chromosomal anomalies in macaques and for understanding the contribution of chromosomal anomalies to reproductive loss and congenital malformations in macaques.
Security-driven scheduling for data-intensive applications on grids

Security-sensitive applications that access and generate large data sets are emerging in various areas including bioinformatics and high energy physics. Data grids provide such data-intensive applications with a large virtual storage framework with unlimited power. However, conventional scheduling algorithms for data grids are unable to meet the security needs of data-intensive applications. In this paper we address the problem of scheduling data-intensive jobs on data grids subject to security constraints. Using a security- and data-aware technique, a dynamic scheduling strategy is proposed to improve quality of security for data-intensive applications running on data grids. To incorporate security into job scheduling, we introduce a new performance metric, degree of security deficiency, to quantitatively measure quality of security provided by a data grid. Results based on a real-world trace confirm that the proposed scheduling strategy significantly improves security and performance over four existing scheduling algorithms by up to 810% and 1478%, respectively.
Triptycene-containing bis(phenylethynyl)benzene nematic liquid crystals

We report the synthesis of a new class of nematic liquid crystals with triptycenes built into a p-dialkoxy-bis(phenylethynyl)benzene mesomorphic core. Triptycenes are appended on the center or terminal ring of the mesogen, leading to symmetric liquid crystals and reduced symmetry liquid crystals, respectively. Both types displayed monotropic behavior, with the asymmetric compounds having unusual phase behavior, lacking distinct crystallization transitions, and forming a glassy mesophase. A chiral analogue was found to be non-mesomorphic, but induced chiral nematic phases when doped into achiral triptycene-containing analogues. Rotation is physically hindered normal to the director and, hence, this new liquid crystal architecture may allow for the synthesis of a single component liquid crystal that displays a biaxial nematic phase.
Risk factors associated with longitudinal change in pulmonary function.

In a longitudinal study of pulmonary function, we investigated the relationship between loss of forced expiration over time and a series of potential risk factors, as well as 4 other measures of pulmonary function at initial visit. Data on 1,912 adults tested twice, with an average of 4.7 yr between visits, were used. Of the potential risk factors examined, only age and smoking were consistently associated with increased loss of forced expiratory function in both men and women. Statistically significant differences among ABO blood types and among Pi types were also seen in women, although the direction of these differences was unexpected in that non-Z Pi variant phenotypes showed less decline in pulmonary function than did the most common Pi M phenotypes. Similar patterns of differences were seen in men, although these were not statistically significant. Of 4 initial-visit pulmonary function measures examined, only closing capacity at initial visit was consistently associated with subsequent loss of force...
I/O Limitations in Parallel Molecular Dynamics

We discuss data production rates and their impact on the performance of scientific applications using parallel computers. On one hand, too high rates of data production can be overwhelming, exceeding logistical capacities for transfer, storage and analysis. On the other hand, the rate limiting step in a computationally-based study should be the human-guided analysis, not the calculation. We present performance data for a biomolecular simulation of the enzyme, acetylcholinesterase, which uses the parallel molecular dynamics program EulerGROMOS. The actual production rates are compared against a typical time frame for results analysis where we show that the rate limiting step is the simulation, and that to overcome this will require improved output rates.
Problem Representation and Conflict Dynamics in the Middle East and Northern Ireland

In an effort to explain conflictual and cooperative actions in the Middle East and Northern Ireland at a time (1995–1999) when international structural factors were relatively constant, this article focuses on cognitive factors. Specifically, statements of leaders representing multiple actors in the Israeli–Palestinian and Northern Ireland relationship are examined. Texts from these leaders serve as data for the independent variable, problem representation. Hypotheses argue that the existence and centrality of actor problem representations can help explain behavior, in a manner that adds to more widely used scholarly explanations. More specifically, the article explores the relationship among leaders' “problem representations” and conflict between the entities they lead. Problem representation is measured in three dimensions using Foreign Broadcast Information Service (World News Connection) texts: (1) centrality of enemy image, (2) how inclusive/exclusive the leader is in describing the in-group and principal outgroup, and (3) the key definition of the problem (coded in terms of three strategies: justice, governance, or threat). Conflict, the dependent variable, is measured in terms of KEDS-TABARI event data on deeds (not words) in the Israeli–Palestinian and Northern Ireland conflicts. Strikingly, the analysis finds that Israeli actions are strongly related to prior and current Palestinian leaders' problem representations, much more than they are to Israeli leaders' problem representations. Similarly, Palestinian actions are found to have a clear relationship with prior and current Israeli leaders' problem representations, much more than they are with Palestinian leaders' problem representations. These results are particularly strong when the problem representation is one of the overall political leadership on the “other” side. Additionally, in-group and out-group inclusivity are the most significant predictors of actions. For Northern Ireland, the same two themes prevail, although not as strongly: there is a clear statistical relationship between each side's problem representations and the other side's actions, stronger in fact than the relationship between their own side's representations and actions. Also, in-group and out-group inclusivity produce a strong statistical relationship with conflict and cooperation. Finally, results are compared with a “tit-for-tat” hypothesis, and found to embellish that hypothesis.
Multiple methionine sulfoxide reductase genes in Staphylococcus aureus: expression of activity and roles in tolerance of oxidative stress.

Staphylococcus aureus contains three genes encoding MsrA-specific methionine sulfoxide reductase (Msr) activity (msrA1, msrA2 and msrA3) and an additional gene that encodes MsrB-specific Msr activity. Data presented here suggest that MsrA1 is the major contributor of the MsrA activity in S. aureus. In mutational analysis, while the total Msr activity in msrA2 mutant was comparable to that of the parent, Msr activity was significantly up-regulated in the msrA1 or msrA1 msrA2 double mutant. Assessment of substrate specificity together with increased reactivity of the cell-free protein extracts of the msrA1 mutants to anti-MsrB polyclonal antibodies in Western analysis provided evidence that increased Msr activity was due to elevated synthesis of MsrB in the MsrA1 mutants. Previously, it was reported that oxacillin treatment of S. aureus cells led to induced synthesis of MsrA1 and a mutation in msrA1 increased the susceptibility of the organism to H2O2. A mutation in the msrA2 gene, however, was not significant for the bacterial oxidative stress response. In complementation assays, while the msrA2 gene was unable to complement the msrA1 msrA2 double mutant for H2O2 resistance, the same gene restored H2O2 tolerance in the double mutant when placed under the control of the msrA1 promoter. However, msrA1 which was able to complement the oxidative stress response in msrA1 mutants could not restore the tolerance of the msrA1 msrA2 mutants to H2O2 when placed under the control of the msrA2 promoter. Additionally, although the oxacillin minimum inhibitory concentration of the msrA1 mutant was comparable to that of the wild-type parent, in shaking liquid culture, the msrA1 mutant responded more efficiently to sublethal doses of oxacillin. The data suggest complex regulation of Msr proteins and a more significant physiological role for msrA1/msrB in S. aureus.
Platelet-activating factor in surfactant preparations

Abstract Surfactant administration is used for treatment of neonatal respiratory distress syndrome. We studied whether currently used surfactant preparations contain platelet-activating factor (PAF), a potent lipid mediator produced by fetal lungs. Three surfactant preparations from animal sources contained between 36 and 218 pmol of PAF per mL, whereas PAF was undetectable in an artificial surfactant. Based on current recommendations, about 144-654 pmol PAF would be administered per dose of natural surfactant, sufficient to exert possible physiological effects on the lung. The action of PAF may be exacerbated by low activity of PAF-acetylhydrolase, which inactivates PAF, in tracheal fluid from infants with respiratory distress syndrome.
Young intragenic miRNAs are less coexpressed with host genes than old ones: implications of miRNA–host gene coevolution

MicroRNAs (miRNAs) have emerged as key regulators of gene expression. Intragenic miRNAs account for ∼50% of mammalian miRNAs. Classic studies reported that they are usually coexpressed with host genes. Here, using genome-wide miRNA and gene expression profiles from five sample sets, we show that evolutionarily conserved (‘old’) intragenic miRNAs tend to be coexpressed with host genes, but non-conserved (‘young’) ones rarely do so. This result is robust: in all sample sets, the coexpression rate of young miRNAs is significantly lower than that of conserved ones even after controlling for abundance. As a result, although young miRNAs dominate in human genome, the majority of intragenic miRNAs that show coexpression with host genes are phylogenetically old ones. For younger miRNAs, extrapolation of their expression profiles from those of their host genes should be treated with caution. We propose a model to explain this phenomenon in which the majority of young miRNAs are unlikely to be coexpressed with host genes; however, for some fraction of young miRNAs coexpression with their host genes, initially imbued by chromatin level effects, is advantageous and these are the ones likely to embed into the system and evolve ever higher levels of coexpression, possibly by evolving piggybacking mechanisms.
Minority Chairs and Congressional Attention to Minority Issues: The Effect of Descriptive Representation in Positions of Institutional Power

Objectives Marginalization of minority issues from the congressional agenda is widely recognized as a hurdle to the functional representation of African Americans and Latinos. This article examines whether the descriptive representation of minorities in positions of influence helps to address this marginalization. Methods Logistic regression analysis of over 27,000 hearings held in the U.S. House of Representatives between 1979 and 2008 examines whether congressional hearings addressing minority interest issues were more likely to occur under Latino and African-American committee and subcommittee chairs. Results Findings reveal hearings chaired by Latinos and African Americans were more likely to address civil rights, social welfare, and housing issues. Conclusion These findings confirm that descriptive representation in positions with influence over committee agendas facilitates institutional attention to minority issues, and suggests that the acquisition of institutional power by black and Latino representatives is critical to the functional representation of minority interests.
Predicting Network Response Times Using Social Information

Social networks and discussion boards have become a significant outlet where people communicate and express their opinion freely. Although the social networks themselves are usually well-provisioned, the participating users frequently point to external links to substantiate their discussions. Unfortunately, the sudden heavy traffic load imposed on the external, linked web sites causes them to become unresponsive leading to the âFlash Crowdsâ effect. In this paper, we quantify the prevalence of flash crowd events for a popular social discussion board (Digg). We measured the response times of 1289 unique popular websites. We were able to verify that 89% of the popular URLs suffered variations in their response times. By analyzing the content and structure of the social discussions, we were able to forecast accurately for 86% of the popular web sites within 5 minutes of their submission and 95% of the sites when more (5 hours) of social content became available. Our work indicates that we can effectively leverage social activity to forecast network events that will be otherwise infeasible to anticipate.
Scale-invariant registration of monocular stereo images to 3D surface models

We present an approach for scale recovery from monocular stereo images of an endoscopic camera with simultaneous registration to dense 3D surface models. We assume the camera motion to be unknown or at least uncertain. An example application is the registration of endoscope images to pre-operative CT scans that allows instrument navigation during surgical procedures. The application field is not restricted to the medical field. It can be extended to registration of monocular video images to laser-based surface reconstructions in, e.g., mobile navigation area or to autonomous aircraft navigation from topological surveys. A novel way for depth estimation from arbitrary camera motion is presented. In this paper, we focus on the robust initialization of the system and on the scale recovery for the reconstructed 3D point clouds with accurate registration to the candidate surfaces extracted from the CT data. We provide experimental validation of the algorithm with data obtained from our experiments with a phantom skull.
A compact time‐of‐flight mass spectrometer for the structural analysis of biological molecules using laser desorption

A compact laser-desorption time-of-flight mass spectrometer using a 600 ps nitrogen laser and 1 Gsample/s transient recorder is described. The instrument incorporates two electrically-isolatable, reflecting flight tubes designed for subsequent configuration of the mass spectrometer as a tandem instrument. In this first report, we compare mass resolution in the laser-desorption mass spectra of an organic dye, sinapinic and caffeic acid matrices, and several small peptides. For directly desorbed ions, peak widths are generally of the order of 11 to 13 ns, so that mass resolution increases with increasing mass. For peptide ions in the range of 500 to 1000 u, formed by matrix-assisted desorption, peak widths range from 9.5 to 17.6 ns and increase with mass. However, better than unit mass resolution (1600 to 2400) is maintained throughout this mass range. Mass measurement accuracy is better than 0.1 u using a single calibration peak and a prompt start trigger pulse. Prospects for extending mass range and resolution are discussed.
Overlap perturbation methods for computing alchemical free energy changes: variants, generalizations and evaluations

The efficient and reliable computation of relative free energy changes for alchemical mutation is very important in biomolecular simulations. In this study we examine the utility of computing alchemical free energy changes using overlap perturbation techniques. These techniques include both the overlap histogram method and the overlap sampling method (a fully optimized version of the overlap sampling technique is equivalent to Bennett's method), and commonly combine sets of perturbations from both alchemical states of interest to improve a free energy calculation. In addition, we propose new variants, present generalized formulas for overlap perturbation techniques and demonstrate differences from the prevailing direct averaging approach used in alchemical free energy calculations. These overlap perturbation methods can be applied to either equilibrium or non-equilibrium free energy simulations. The alchemical transformation of an adenosine molecule in aqueous solution is used as an example for evaluating...
Sequence of Plasmodium falciparum chromosome 12

The human malaria parasite Plasmodium falciparum is responsible for the death of more than a million people every year. To stimulate basic research on the disease, and to promote the development of effective drugs and vaccines against the parasite, the complete genome of P. falciparum clone 3D7 has been sequenced, using a chromosome-by-chromosome shotgun strategy. Here we report the nucleotide sequence of the third largest of the parasite's 14 chromosomes, chromosome 12, which comprises about 10% of the 23-megabase genome. As the most (A + T)-rich (80.6%) genome sequenced to date, the P. falciparum genome presented severe problems during the assembly of primary sequence reads. We discuss the methodology that yielded a finished and fully contiguous sequence for chromosome 12. The biological implications of the sequence data are more thoroughly discussed in an accompanying Article (ref. 3).
Nerve growth factor dependent changes in electrophysiology measured in a neurotrophic electrode

We describe here a neurotrophic electrode designed to improve long-term reliability and signal-to-noise in a brain-device interface. Our electrode consists of a fine microwire inside a polyimide tube. The polyimide tube is filled with nerve growth factor (NGF) incorporated into a fibrin matrix. Our goal is to have a neurite grow into the tube. The close apposition between neurite and the recording wire should enhance signal-to-noise. The physical connection between device and tissue should improve reliability. We have implanted complete devices in 4 rats. Each rat gets a four-electrode device implanted in the barrel cortex of each hemisphere. Each electrode is filled with a different test substance. One control tube contains only saline, and another contains only the fibrin matrix. The other two electrodes in each array are filled with different concentrations of NGF. Once weekly following the implant, each rat is sedated, and electrical activity in each of the electrodes recorded. Electrodes in 5 of the 8 implants exhibited multi-unit spindling activity. A direct comparison of the amplitude of action potentials over time in each of the types of implants shows that the presence of NGF within the polyimide tube leads to an increase in action potential amplitude.
TREASURY INVESTMENT FUNDS AND OPEN‐MARKET OPERATIONS*

TREASURY INVESTMENT FUNDS now amount to about $39 billion, compared with less than $7 billion in I940. Securities held for these funds account for I 5 to 20 per cent of the total federal debt. Holdings for such funds are more than twice as great as the combined holdings of the Federal Reserve Banks. For purposes of this paper it is not necessary to estimate precisely the future rate of increase in these funds. It will suffice to point out tliat, barring statutory changes, further increases may be anticipated.' Although there is a large number of trust funds handled by the Treasury, a few of them account for the bulk of the total. Among the larger of the funds are the Federal Old Age and Survivors Insurance Trust Fund, the Unemployment Trust Fund, the National Service Life Insurance Fund, and the Railroad Retirement Account. The purpose of this paper is to indicate the powers and the limits on the powers of the Treasury to invest trust account funds in marketable government securities, to indicate the way in which these powers have been used, and to raise the question about future policy with respect to Treasury use of investment funds for open market operations. Efforts by the Secretary of the Treasury to influence the market for government securities are not new. As far back as I 790 a special board was established to buy in the open market any federal debt issues that fell below par.2 Although the purpose of such operations has varied from time to time, Treasury efforts to support the government credit and the government security market have been a more or less continuous part of our financial machinery.'
ESTIMATING DETECTION PROBABILITY PARAMETERS FOR PLETHODON SALAMANDERS USING THE ROBUST CAPTURE–RECAPTURE DESIGN

Abstract Recent concern over global amphibian population declines has highlighted a need for more extensive, rigorous monitoring programs. Two sources of variation, spatial variation and variation in detection probability, make the design and implementation of effective monitoring programs difficult. We used Pollock's robust design in a 3-year capture–recapture study to estimate detection probability and temporary emigration for Plethodon salamanders in Great Smoky Mountains National Park (Tennessee/North Carolina), USA. We used 12 competing models to determine the importance of temporary emigration, and we explored temporal and behavioral effects on conditional capture probabilities. The top 4 models all included random temporary emigration, and Akaike model weights indicated that this parameter was the most important. Models that contained behavioral effects in capture probabilities were selected more often than models with equal capture probabilities for marked and previously unmarked individuals. The ...
Structural vibration for robotic communication and sensing on one-dimensional structures

In this paper, structure-borne vibrations in a one-dimensional structure are examined as a means of communication and sensing for networks of robots. The concept is inspired by the observation that insects may use structural vibrations to communicate and to detect features of their environment. A 12 × 5 × 6 cm mobile robot capable of traversing an acoustically favorable structure is presented. A technique for measuring distance between robots and communicating commands to robots using vibrations generated on a common one-dimensional substrate are presented, and demonstrated through preliminary experimental results. Design considerations for this type of system are also discussed.
Independent Jamaica Faces the Outside WorldAttitudes of Elites After, Twelve Years of Nationhood

A re-study of attitudes toward global alignments among 83 leaders in 1974, 12 years after political independence, is compared with a study completed just before independence in 1961–1962 in the new Caribbean state of Jamaica. A striking decline in favorable attitudes toward Jamaica's alignment with Western nations occurred, from 71% of the leaders in 1962 to 36% in 1974. New and volunteered preferences were for alignment with Third World countries or with any country as long as Jamaica's self-interest was served. The social characteristics and differential roles of leaders affected their attitudes toward foreign affairs at both times. Older, middling educated, white and Chinese, relatively wealthy, and economic or religious leaders as opposed to political, labor, or other leaders were most likely to prefer the West in 1974. Also, the values of leaders affected their foreign-policy attitudes; Reactionaries and Conservatives, Nonegalitarians, non-Nationalists, to some extent Anglo-European identified leaders, and Authoritarians as opposed to Full Democrats were most likely to prefer the West. A path model containing six causal variables explains 54% of the variance in foreign policy attitudes in 1962 and 43% in 1974.
Diversity in Terrestrial Cave Communities

Local species diversity of terrestrial arthropods was determined from a combination of trapping and census in an area of variable passage type in Flint Ridge Cave System in Mammoth Cave National Park, Kentucky. We measured evaporative rate, substrate moisture, substrate organic content, predictability and stability of food and microclimate, substrate diversity, and intensity of flooding. We found significant correlations of species diversity with substrate diversity, substrate organic content, and intensity of flooding.
Professional Autonomy Reconsidered: The Case of Czech Medicine under State Socialism

The opening of the formerly closed, state socialist societies of East Central Europe has provided the opportunity to bring new empirical evidence to bear upon models of profession-state relations developed in pluralist western societies. The classic view of Tocqueville and Durkheim has been that professions are an intermediary group linking individuals and the state. Although not always explicitly stated, this model served as the basis for scholarly work on the professions in the post-World War II period, where it (more or less) fit the image of a differentiated pluralist society. Most work on the professions was based on the Anglo-American case.But even in the United States, state support was more central to maintaining professional authority than was originally thought. Without explicitly discarding the model, Freidson (1970) introduced a distinction between corporate and technical (clinical) autonomy that provided a way out of the paradox he identified, that both aspects of professional autonomy are protected by the state. Corporate autonomy refers to the political power of the organized profession to define the social and economic context of professional work, and clinical autonomy, to the control of decision making in the workplace. Testing his hypothesis on the United States, the United Kingdom, and the Soviet Union, Freidson argued that despite differing degrees of corporate autonomy, the medical profession retained clinical control of decision making, the core of professional autonomy, even in the extreme case of the former Soviet Union.
Flooding hydrology and peak discharge attenuation along the middle Araguaia River in central Brazil

Abstract The Araguaia River in central Brazil is the largest river draining the Brazilian savanna. Located in a tropical wet-dry climate, the middle Araguaia River has an extensive and complex alluvial floodplain composed of a mosaic of geomorphologic units, dense alluvial forest, and many floodplain lakes. The Araguaia River is not currently dammed, and thus it provides an opportunity to analyze flooding hydrology in a relatively un-altered tropical system. Using average daily discharge measurements from 1975 to 2011, we analyze patterns of peak discharge attenuation (defined as the reduction in absolute peak discharge in m 3 s − 1 ). We link peak discharge attenuation to bankfull discharge, explore whether peak discharge attenuation results in increased base level flows in the dry season following peak discharge, and use a simplified short-term water budget to determine whether peak discharge attenuation results in the loss of discharge from the channel over the flooding season (November to May). In addition, we explore other potential factors causing peak discharge attenuation, including surface water connectivity between the channel and floodplain lakes and floodplain lake area change between the dry season and the wet season. Although fluvial connectivity between the main channel and the floodplains starts before bankfull stage, we find that large peak discharge attenuation (up to 30% reduction in peak discharge) in the middle Araguaia usually occurs when the river rises above bankfull discharge. The river flow that is lost to the floodplain and floodplain lakes when peak discharge attenuation occurs usually returns to the channel by the end of the flooding season. However, the odds of increased baseflows in the dry season after flooding seasons with peak discharge attenuation are higher compared to flooding seasons without peak discharge attenuation for one of the studied reaches. Some types of floodplain lakes greatly increase in area from the dry season to the wet season, and many floodplain lakes become connected via surface water in the wet season. We have not found similar examples of peak attenuation in this type of tropical wet-dry floodplain system, indicating that the middle Araguaia River may be a unique system or that further research is needed.
Pairing Investigation on Iodine Intake of Lactating Women and Breast Feeding Infants

Objective To survey iodine intake of breast feeding infants and lactating women.Methods Urinary iodine determination was paired between breast feeding infants and their lactating mothers,and iodine intake was calculated by urinary iodine multiplying urinary output.Results There was obvious correlation of iodine intake between breast feeding infants and their lactating mothers.Correlation coefficient was respectively 0.338(P0.01) in 155-pair infants(1year) and their lactating mothers and 0.437 (P0.01) in 128-pair infants(9 month) and their lactating mothers. The regression equation was =103.3+0.19x and =83.98+0.26x,respectively.Conclusions Computative iodine intake between breast feeding infants and their lactating mothers can evaluate their iodine nutrition.
Nonsurgical treatment of ectopic pregnancy.

"Never allow the sun to set on a patient with a suspected ectopic pregnancy without taking her to surgery."
The infected mediastinum. Successful treatment in the presence of external cardiac prosthetic material.

An infection of the mediastinum in the presence of external cardiac prosthetic material may be successfully managed with wound debridement, local antibiotic irrigation, and systemic antibiotic therapy without removal of that prosthetic material. This approach should be undertaken before the more radical treatment, removal of the foreign material, is considered.
A framework for analysis of research risks and benefits to participants in standard of care pragmatic clinical trials.

Background/Aims:Standard of care pragmatic clinical trials that compare treatments already in use could improve care and reduce costs, but there is considerable debate about the research risks of standard of care pragmatic clinical trials and how to apply informed consent regulations to such trials. We sought to develop a framework integrating the insights from opposing sides of the debate.Methods:We developed a formal risk–benefit analysis framework for standard of care pragmatic clinical trials and then applied it to key provisions of the US federal regulations.Results:Our formal framework for standard of care pragmatic clinical trial risk–benefit analysis takes into account three key considerations: the ex ante estimates of risks and benefits of the treatments to be compared in a standard of care pragmatic clinical trial, the allocation ratios of treatments inside and outside such a trial, and the significance of some participants receiving a different treatment inside a trial than outside the trial. T...
Citizen perceptions of general-purpose and special district governments: A comparative analysis

Special districts comprise over 40% of local governments, prompting debate on the merits of general versus special entities. Previous research focused on relative cost-efficiency and tended to ignore how special districts impact government accountability. This study fills a critical need by testing how type of government (general versus special) impacts citizen awareness of and familiarity with government, a precondition for accountability. Drawing from two theoretical perspectives (institutional reform and public choice), we used survey research to assess familiarity with the goals and performance and financial practices of local governments in Indiana. Our study participants were more aware of and familiar with general than special governments, which supports the institutional reform perspective more than public choice. We conclude that efforts to improve accountability should be expanded to include special districts.