cssi/SciSciGPT-SciSciNet huggingface dataset:
Noisy data-rate limited estimation: renewal codes

We consider the problem of estimating the state of a system whose observations are transmitted from the sensor to the estimator over a binary symmetric channel (BSC). A coder at the sensor encodes its data into channel inputs. The estimator receives the channel output and estimates the state. There is a perfect 'reverse' channel from the estimator back to the coder, so the coder has full knowledge of the decoder. Such a system model is appropriate when the coder is power limited, but the decoder is not. The existence of a stable estimator (i.e. one with bounded estimation error) depends on two parameters: the degree of instability of the system, and the channel error probability. We present estimators for a subset of these parameters. It is difficult to design of a coder-decoder pair for a stable estimator. Classical codes for the BSC cannot be used, because they introduce large coding delays, hence large errors in the state estimate. We need codes that simultaneously impose very small delays and reduce decoding errors. These considerations point to a rich class of design problems that lie in the intersection of real-time control and communication. Previous work addressed this problem using a non-constructive random coding argument. The estimator presented here is constructive and has very low complexity. Surprisingly, too, our estimator works for parameter values not covered by the random coding argument.
Acute Pulmonary Lipopolysaccharide Tolerance Decreases TNF-α without Reducing Neutrophil Recruitment

Pulmonary LPS exposure plays a key role in exacerbation of lung diseases such as chronic obstructive pulmonary disease and asthma. However, little is known about the effects of repeated LPS exposure in the lung microenvironment. We have developed a novel murine model of pulmonary LPS tolerance induced by intratracheal (i.t.) administration of LPS. First, we show that pulmonary LPS exposure does not induce whole-body refractoriness to systemic LPS, because i.t. administration followed by i.p. administration did not decrease plasma TNF-alpha. However, a local refractory state can be induced with two i.t. LPS exposures. Pulmonary LPS tolerance was induced by i.t. administration of 100 ng LPS at time 0 and 48 h. Nontolerant mice received PBS at time 0 and LPS at 48 h. Bronchoalveolar lavage levels of TNF-alpha were significantly attenuated in tolerant mice vs nontolerant mice (1597 pg/ml vs 7261 pg/ml). TNF-alpha mRNA was significantly reduced in bronchoalveolar lavage cells (5-fold) and lung tissue (10-fold). No reduction was seen in neutrophil numbers in the bronchoalveolar lavage fluid, myeloperoxidase activity, or expression of neutrophil chemoattractants CXCL1 and CXCL2, reflecting the specificity of the response. The reduction in TNF-alpha was accompanied by a significant increase in soluble receptors, TNF-SRI (159 pg/ml vs 206 pg/ml) and TNF-SRII (1366 pg/m vs 2695 pg/ml). In conclusion, pulmonary LPS tolerance results in a specific reduction in TNF-alpha expression, while the neutrophilic response is unaffected. This response may be a mechanism to limit tissue damage by reducing TNF-alpha levels, while still maintaining the antimicrobial capacity of the lung.
The Soviet study of the Barefooted Flight of the Kazakhs

The defeat, devastation and exile of the Kazakhs in the early eighteenth century, commonly known as the Barefooted Flight, was the nation's most distressing pre-Soviet calamity. Kazakh nation-building and official remembrance projects – commemorated in state ceremonies, public education and popular culture – portray an uninterrupted, centuries-old practice of tribute to local heroes who challenged the foreign aggressors. Twentieth-century Kazakh and Russian intellectuals in the Soviet and post-Soviet eras studied and enshrined these events based on published, secondary sources, rarely giving attention to the thin trail of documents preserved in state archives. The historiography of the Barefooted Flight exposed a trend in how politically convenient historical lessons shaped the interpretation of events. By the end of the Soviet Union, some archival material was introduced, it was but misquoted so as not to challenge the current interpretation.
Michael Mustill: a reminiscence

The arbitration world lost a giant when Michael Mustill departed in April of this year, just a few days short of his 84th birthday. A man of enormous intellect and wit, with a fine capacity for sincere friendship, this generous Yorkshireman enriched us through contributions as counsel, judge, scholar, and mentor. Lord Mustill sat as judge successively in the High Court of London, the English Court of Appeal and the UK House of Lords, the last of which morphed into the Supreme Court of the United Kingdom. After retirement from the bench, his service as arbitrator touched a wide spectrum of disputes, implicating expertise in both private and public law. His treatise on commercial arbitration shines for a robust analysis of arbitration law,1 as does the innovative and seriously brilliant exploration of what the ‘new lex mercatoria’ might (or might not) comprise.2 He served his alma mater, Cambridge, as Arthur Goodhart Professor, Fellow of St. John’s College, and Honorary President of the Cambridge University Law Society. Among his judicial pronouncements in the field of international arbitration, several will be ‘worth a detour’ as the Michelin Guide says of an exceptionally good gourmet restaurant. In this connection, we might stop to consider the House of Lords decision in the Channel Tunnel case,3 for which Lord Mustill delivered a majority speech addressing the vexing question of when and how courts in one country should play a part …
Cellulase from Ruminococcus albus and Mixed Rumen Microorganisms

Cellulase in the cultural filtrates of Ruminococcus albus and cellulase extracted from mixed rumen microorganisms were investigated with acid-swollen cellulose and carboxymethylcellulose as substrates. Maximal activity occurred at approximately pH 5.8 and 47 C. Apparent Michaelis constants (Km) varied between 0.53 and 0.02% carboxymethylcellulose, depending on the level of activity and the method of assay. R. albus cellulase has a lower Km value than the enzyme extracted from mixed rumen microorganisms. Antisera from rabbits immunized with a cellulase preparation from R. albus inhibited the cellulolytic activity of both systems. Based on the relative degree of inhibition, approximately 20% of the cellulase of the mixed rumen microorganisms was immunologically similar to R. albus cellulase. Ratios of activity in different assay techniques showed the two sources of activity to be similar in the mechanisms of degradation. However, glucose is the main product of cellulose degradation by mixed rumen microorganisms, and cellobiose is the product of degradation by R. albus.
Tuning fork MEMS gyroscope for precision northfinding

We report northfinding results using an out-of-plane tuning-fork MEMS gyroscope with performance approaching navigation grade. Angle random walk is less than 0.003 °/√hr, and in-run bias instability is less than 0.02 °/hr at an Allan variance sampling time of one hour. A compact (< 20 cm3) prototype northfinder containing 3 gyros and 3 accelerometers is indexed to compensate for gyro and accelerometer bias drift and non-repeatability, providing northfinding precision of ±4 milliradians in 4 minutes averaging time. Gyro magnetic sensitivity is less than 0.004 °/hr/Gauss.
Helping Hands: Race, Neighborhood Context, and Reluctance in Providing Job-Finding Assistance

In order to explain persistent racial inequality, researchers have posited that black Americans receive fewer job benefits from their social networks because of their reluctance to provide assistance to others who are looking for work. We test this idea on a national scale using geo-coded data from the General Social Survey. Our results show that, on average, blacks offer more frequent job-finding assistance to their friends than do whites. However, additional analyses reveal that race-based job-finding assistance is context dependent, as blacks living in areas characterized by concentrated black poverty have lower odds of helping others search for jobs than members of other races and in other community contexts.
Ultraviolet observations of M1-2 (= VV 8)

First IUE spectrograms of the peculiar emission-line object M1-2 (= VV 8) are presented. In the wavelength region 1150-3200 A this object is characterized by emission lines superposed on a moderately strong continuum. Some ultraviolet and optical properties of M1-2 are discussed in the context of symbiotic stars and protoplanetary and planetary nebulae. An E(B-V) extinction of 0.37 mag is obtained from the ratio of the He II flux at 1640 and 4686 A and is compared with values derived from other parameters. The ultraviolet observations suggest that M1-2 is a young, high-density planetary nebula of excitation class 5 or 6 with characteristics similar to IC 4997.
Fourth Graders' Heuristic Problem-Solving Behavior.

In the fourth grade, students may be asked to solve challenging mathematical problems that require a careful analysis of the conditions of the problem and finally a synthesis to arrive at a correct solution. Research (e.g., Kantowski, 1977; Lucas, 1974; Stern & Keislar, 1967) has shown that teaching a set of strategies to students can improve problem-solving abilities. Polya discussed methods that help in solving problems in How to Solve It (1957). These methods are not in an appropriate form for young children. Since most fourth graders are at the concrete operational stage of Piaget's cognitive development classification, Polya's methods have to be adapted in language, number, and complexity. The questions of this study were (a) can fourth graders who are concrete operational acquire specific heuristics and use them appropriately and effectively to become better problem solvers and (b) are there differences in the use of specific heuristics by children at the early and late substages of the concrete operational stage? A clinical methodology was used to identify variables, relations, and hypotheses for future research. Anecdotes serve to support and clarify generalizations.
Study on the lipid composition of aging Fischer-344 rat lymphoid cells: effect of long-term calorie restriction.

Long-term calorie restriction (LCR) is widely known to increase the survival rate of laboratory rodents and appears to retard the aging and senescence process. The present study was undertaken in Fischer-344 male rats maintained onad libitum (AL) or LCR (40% less food intake than AL starting at 6 weeks of age). Age-associated changes in the proliferative response of lymphoid cells to mitogenic stimuli were studied in relation to alterations in the fatty acid composition of adherent and nonadherent-enriched subpopulations of spleen cells. Increases in spleen cell long-chain highly unsaturated fatty acids (20∶4, 22∶4 and 22∶5) were accompanied by decreases in linoleic acid (18∶2) in aging AL-fed rats. However, LCR stabilized levels of 18∶2 and prevented the rise in highly unsaturated fatty acids. In addition, LCR markedly modulated the fatty acid profiles of thymocytes and bone marrow cells. A 70% decline in concanavalin A (Con A) stimulated [3H]thymidine uptake of spleen cells from AL animals was normalized by LCR. Splenic reduced glutathione (GSH), a potential modulator of the mitogenic response, was unaffected by age and nutritional regimen. Thus, normalization of lymphoid cell fatty acid composition by LCR parallels the preservation of mitogenic responsiveness to Con A.
Measuring program outcomes in Tucson.

“The data available are never what you need; the data you need are never available.” This familiar attempt at humor that students in graduate-level statistics courses have heard for decades takes on serious meaning in this era of cornputerized record keeping. Today, instead of small quantities of data to test this variant of Murphy’s Law, we often create massive data bases that answer all kinds of questions-except the ones that are most relevant for program planning. Nowhere is this more apparent than in research on program outcomes for chronic mental patients. Elaborate studies of patients’ hospitalization and rehospitalization rates, employment histories, symptomatology, and levels of functioning answer many administratively relevant questions but frequently fail to probe the more human dimensions of what happens to patients after they have been placed in specific programs (1,2). In my visits to many programs for the chronic mentally ill throughout the United States, I have often observed major disparities between what the numbers tell and what the programs actually do. Sometimes the numbers are unduly optimistic, to say the least; mea-
The Antecedents and Implications of Interracial Anxiety

Drawing on previous theorizing from both the prejudice and social anxiety literatures, a model of the antecedents and implications of intergroup anxiety is offered. It is argued that a lack of positive previous experiences with outgroup members creates negative expectancies about interracial interactions, which result in intergroup anxiety. This anxiety is posited to result in heightened hostility toward outgroup members and a desire to avoid interacting with outgroup members. Study 1 examined White participants' responses to interacting with Black people using a range of self-report measures; the associations between these responses supported the relationships outlined in the model. Study 2 explored White participants' responses to an anticipated interaction with a Black person or a White person. The findings revealed that high levels of anxiety about an interaction with a Black person, but not a White person, were associated with a lower likelihood of returning for the interaction.
Diastematomyelia in children: treatment outcome and natural history of associated syringomyelia.

To quantify the long-term outcome of children with diastematomyelia and the implication of syringomyelia in the natural history. Retrospective study of 17 children (nine girls and eight boys) with diastematomyelia operated during 1989–2004. Mean age at diagnosis was 3.4 years (range 5 days–12 years), mean follow-up was 5 years; 14 had excision of spur and cord untethering, 3 had excision of spur alone. The bony spur was in the lumbar region in 12 and thoracic in 5 patients. Syringomyelia was present in eight (47%), associated with bony spur between L1 and 4 (p=0.088), spina bifida occulta in ten (58.8%), and spinal lipoma in one (6%). Preoperative Necker Enfants Malades (NEM) scores were 17 in eight patients, 16 in four, 15 in three, 13 in one, and 12 in one patient. Presenting neurological deficits were motor in eight, sensory deficits in three, and anal incontinence in one patient. There was improvement of NEM scores postoperatively in five patients only, but still with residual deficit. Repeat spur excision and cord untethering was performed in three patients for neurological deterioration 1–4 years after first operation. On postoperative MRI scans syringomyelia remained unchanged in all eight patients. There were one skin infection, one transient motor deterioration, and one patient with sensory deficit after surgery. Prophylactic operations were associated with the best clinical outcome. Despite improvement, all patients with established preoperative deficit still had residual neurological deficits at their last follow-up. The associated syringomyelia remained unchanged after surgery, indicating that it does not contribute to the neurological syndrome.
Tonotopic representation of auditory responses using self-organizing maps

A self-organizing neural network model called CORMAP has been developed to represent the tonotopic organization of the auditory cortex of an FM bat. The map self-organizes purely based on external input stimulus parameters. The weights in the competitive layer self-organizes into a topological map of the input space. This process in turn allows the representation of the similarity of inputs into the proximity of excited neurons. An additional output layer interconnected with the self-organized layer in the CORMAP model provides a mechanism to observe the functional characteristics of individual neurons. The CORMAP model is biologically motivated and the functional characteristics of the neuron used in the self-organizing layer were obtained directly from neurophysiological experiments. CORMAP demonstrates a plausible model for representing cortical activities in response to external stimulus inputs.
Infinite inflations of crumpled cubes

Abstract Based upon recent results characterizing Q -manifolds, this paper sets forth an explicit method for retooling certain pathology arising in finite dimensional manifolds as comparable pathology in the Hilbert cube Q . In particular, with reference to an example constructed by the author and J.J. Walsh, it presents an upper semicontinuous decomposition G of Q into points and a null sequence of cellular arcs such that the associated decomposition space is not a Q -manifold, and it also provides a new procedure for embedding finite dimensional compacta as wild subsets of Q .
Does Environmental Protection Lead to Slower Productivity Growth in the Chemical Industry

Efficiency and productivity growth is measured at the three-digit SIC level for six chemical industries for 1988–1993. The directional distance function is used to measure the lost chemical manufacturing output and the overproduction of toxic chemical releases. Total factor productivity growth is decomposed into a product of efficiency change and technical change. Accounting for toxic chemical releases, productivity grows at anannual rate of between 2.4% and 6.9%. We find no evidence that environmental protection measures reduce productivity growth.
A Mouse Model of Uterine Leiomyosarcoma

We are using an approach that is based on the cre/loxP recombination process and involves a binary system of Cre-producing and Cre-responding transgenic mice to achieve ubiquitous or tissue-specific expression of oncoproteins. To develop mouse models of tumorigenesis, Cre-producers are mated with responder animals carrying a dormant oncogene targeted into the 3′ untranslated region of the locus encoding cytoplasmic β-actin (actin cassette). Production of oncoprotein from a bicistronic message is accomplished in bitransgenic progeny by Cre-mediated excision of a segment flanked by loxP sites that is located upstream from the oncogenic sequence. Widespread Cre-dependent activation and expression of an actin-cassette transgene encoding the T antigens of the SV40 early region (SVER) commencing in embryos was compatible with normal development and did not impair viability. However, at ∼3 months of age, all female animals developed massive uterine leiomyosarcomas, whereas practically all males exhibited enormously enlarged seminal vesicles because of pronounced hyperplasia of the smooth muscle layers. In addition, because of smooth muscle hyperproliferation, marked dilation of the gallbladder was observed in mice of both sexes. To begin exploring aberrant signaling events in the SVER-triggered tumorigenic pathways, we analyzed the expression profile of leiomyosarcomas by DNA microarray analysis.
Sample size determination for lower confidence limits for estimating process capability indices

Abstract Until recently, estimates of process indices have been point estimates. However, a more appropriate estimate would be provided by a confidence interval. In this case, a one sided interval is necessary, since the real interest is in how small the process index can be, and is called a lower confidence limit. Recent work by Chou et al. (Lower confidence limits on process capability indices. Journal of Quality Technology 1990;22(3):223–29), Kushler and Hurley (Confidence bounds for capability indices. Journal of Quality Technology 1992;24(4):188–95), and Franklin and Wasserman (A note on the conservative nature of the tables of lower confidence limits for Cpk with a suggested correction. Communications in Statistics: Simulation and Computation 1992;21(4):1165–69) have provided exact and approximate formulas to determine these lower confidence limits for Cp and Cpk. In addition, recent work by Boyles (The Taguchi capability index. Journal of Quality Technology 1991;23(1):17–26) has provided approximate formulas to determine the lower confidence limits for Cpm. This paper provides equations to estimate the approximate sample size necessary to achieve a desired confidence limit with specified confidence level. These equations are based on these formulas and are presented for Cp, Cpk, and Cpm. In addition, some observations and recommendations are made.
On the convex case in the positone problem for elliptic systems

On etudie l'existence et la dependance par rapport au parametre α des solutions du systeme: Lμuμ=αfμ(x,u) dans Ω, uμ=o sur ∂Ω, uμ≥o dans Ω, μ=1,...,k, u=(u 1 ,...,u k ), Ω≤Rμ est un domaine borne lisse et Lμ est un operateur differentiel uniformement elliptique a coefficients continus de Holder
Understanding and Efficiency: Habermas’s Concept of Communication Relief

This commentary calls attention to a topic neglected in the scholarly reception of Habermas’s work—the concept of communication relief. In his recent public sphere theory, he classifies different media forms that are necessary for coordinating different types of social action. He identifies three such media forms: linguistic agreement, steering media, and generalized communication. Although communication scholars acknowledge his ideas on linguistic agreement, they have overlooked those on steering media and generalized communication. Accordingly, this analysis focuses more on the latter two media forms, which fall under the broader concept of relief mechanisms. Extending the media theories of Talcott Parsons, Habermas identifies four types of relief mechanisms: money, power, influence, and value commitment. Money and power perform steering media functions that promote efficiency. Influence and value commitment perform generalized communication functions that promote not only efficiency but also understanding. Implications for normative theories of mass-mediated democratic communication are discussed.
Patient satisfaction and rehabilitation services

Abstract Objective: Despite the widespread use of patient satisfaction measures, there has been only a small amount of research and writing on the topic in rehabilitation. This article reviews selectively the large amount of literature on satisfaction in health care, examines work in rehabilitation settings, and highlights issues in patient satisfaction, given the unique circumstances of rehabilitation services. Data Sources: A Medline search was made of the past 10 years using descriptors related to patient satisfaction, rehabilitation, and selected diagnostic categories. Additional sources came from references on satisfaction accumulated by the author over the past 20 years. Study Selection: Because of the voluminous literature, findings from existing reviews were emphasized, particularly those using meta-analytic methods. All articles that involved satisfaction in rehabilitation settings were included. Data Synthesis: Research in health care generally shows high levels of satisfaction. Personal aspects of care, including full communication, are the most important predictors, whereas age, education, and social status show weak relationships with rating levels. Dissatisfied patients tend to seek other providers. Higher satisfaction is associated with patient compliance and better outcomes. Levels of satisfaction are especially high in rehabilitation. Conclusions: Measures of patient satisfaction with rehabilitation should include items regarding progress and degree of return to independent living. Responses of proxies answering in place of patients should not be regarded as equivalent to patients' opinions. The field is in need of standard, validated measures appropriate for various settings.
The invasion window for warmwater fish in clearwater lakes: the role of ultraviolet radiation and temperature

Aim In clear, cold-water lakes, ultraviolet radiation (UV) and temperature are two important stressors that may prevent the establishment of aquatic invasive species by inhibiting the survival of sensitive early life history stages. In this study, we develop a UV–temperature response model to predict the establishment potential of a warmwater fish, largemouth bass (Micropterus salmoides), in a large subalpine lake based on the ability of bass larvae to tolerate UV and temperature stress along a UV–temperature stress gradient. Location Lake Tahoe (California/Nevada, USA). Methods We compared the UV tolerance of largemouth bass larvae to that of the native redside minnow (Richardsonius egregius) in outdoor UV exposure–response experiments. A UV–temperature response model for larval bass was developed that combined the experimentally derived UV exposure response from our outdoor experiments with a temperature response curve derived from the literature. We used the UV–temperature response model to predict reproductive success (i.e. larval survival) over the range of UV exposure and temperature conditions in nearshore Lake Tahoe. The model predictions were validated with in situ incubation experiments at nearshore locations. Results Non-native bass were significantly less UV tolerant than native redside minnows. The UV–temperature response model predicted that larval bass survival varies seasonally, spatially and over depth gradients in nearshore Lake Tahoe and is constrained by UV and temperature conditions. In situ incubation experiments confirmed model predictions. Main conclusions Our findings provide important insights into the potential for species invasion in clear, cold-water lakes that are experiencing significant changes in both temperature and transparency. The conceptual model and approach that we employ is a potentially powerful tool for exploring unanswered questions in invasion biology, including the role of alternate stable states in facilitating invasion and the potential for invasive species to promote ‘invasional meltdown’ through their impacts on water clarity and temperature.
Biochemical and Mass Spectrometric Characterization of Human N-Acylethanolamine-Hydrolyzing Acid Amidase Inhibition

The mechanism of inactivation of human enzyme N-acylethanolamine-hydrolyzing acid amidase (hNAAA), with selected inhibitors identified in a novel fluorescent based assay developed for characterization of both reversible and irreversible inhibitors, was investigated kinetically and using matrix-assisted laser desorption/ionization time-of-flight mass spectrometry (MALDI-TOF MS). 1-Isothiocyanatopentadecane (AM9023) was found to be a potent, selective and reversible hNAAA inhibitor, while two others, 5-((biphenyl-4-yl)methyl)-N,N-dimethyl-2H-tetrazole-2-carboxamide (AM6701) and N-Benzyloxycarbonyl-L-serine β-lactone (N-Cbz-serine β-lactone), inhibited hNAAA in a covalent and irreversible manner. MS analysis of the hNAAA/covalent inhibitor complexes identified modification only of the N-terminal cysteine (Cys126) of the β-subunit, confirming a suggested mechanism of hNAAA inactivation by the β-lactone containing inhibitors. These experiments provide direct evidence of the key role of Cys126 in hNAAA inactivation by different classes of covalent inhibitors, confirming the essential role of cysteine for catalysis and inhibition in this cysteine N-terminal nucleophile hydrolase enzyme. They also provide a methodology for the rapid screening and characterization of large libraries of compounds as potential inhibitors of NAAA, and subsequent characterization or their mechanism through MALDI-TOF MS based bottom up-proteomics.
Morphological integration and the evolution of knuckle-walking

The evolution of knuckle-walking has profound implications for our understanding of the emergence of bipedalism. The modern debate surrounding its evolution is concerned with whether or not it is homologous in chimpanzees and gorillas. Here, this problem is approached using the methods of morphological integration to test hypotheses of patterns and magnitudes of integration in the third manual ray and capitate. If knuckle-walking morphologies are highly integrated and evolve in a correlated bundle (i.e., comprising a functional complex), it seems reasonable that they could have been recruited independently relatively easily in gorillas and chimpanzees, thus increasing the likelihood of homoplasy. If, however, there is no evidence for a knuckle-walking complex, then it seems less likely that chimpanzees and gorillas would have evolved knuckle-walking independently. Results indicate that chimpanzees and gorillas are not characterized by high magnitudes of integration or unique patterns of integration that distinguish them from non-knuckle-walking taxa. This does not support the hypothesis of a knuckle-walking complex, nor does it support the contention that knuckle-walking could have been easily evolved independently in chimpanzees and gorillas. Implications for trait analysis and the evolution of bipedalism are discussed, as are recent analyses supporting the independent origins of knuckle-walking.
Validating image-processing algorithms

This paper describes how to validate image processing algorithms when the algorithm has been designed to produce a numerical output that optimizes a given scalar criterion function having all first and second partial derivatives. The validation technique analyzes the statistical behavior of the algorithm under small random perturbations of its input. This paper gives the theory for the computation of the covariance matrix of the output when the input is perturbed by small random input perturbations. A statistical test is done examining the algorithm output under multiple instances of simulated perturbations and comparing these outputs with the ideal output and the analytically derived covariance matrix. A second level of simulations can be done that examines the test statistics of the hypothesis of the statistical test to determine whether in fact it is distributed in accordance with statistical theory. If the hypothesis is rejected that the output perturbations do not have the analytically predicted covariance matrix, then the image analysis software fails validation.
Elevated levels of endothelin-1 in hepatic venous blood are associated with intrapulmonary vasodilatation in humans

Background Hepatopulmonary syndrome is a pulmonary vascular complication of cirrhosis in which intrapulmonary vasodilatation (IPV) results in hypoxemia. Endothelin-1 (ET-1), produced by proliferating cholangiocytes, has been identified as a mediator of IPV in an animal model of HPS, but the pathophysiology of IPV in humans has not been defined.
Mechanisms of Beat-to-Beat Regulation of Cardiac Pacemaker Cell Function by Ca2+ Cycling Dynamics

Whether intracellular Ca2+ cycling dynamics regulate cardiac pacemaker cell function on a beat-to-beat basis remains unknown. Here we show that under physiological conditions, application of low concentrations of caffeine (2–4 mM) to isolated single rabbit sinoatrial node cells acutely reduces their spontaneous action potential cycle length (CL) and increases Ca2+ transient amplitude for several cycles. Numerical simulations, using a modified Maltsev-Lakatta coupled-clock model, faithfully reproduced these effects, and also the effects of CL prolongation and dysrhythmic spontaneous beating (produced by cytosolic Ca2+ buffering) and an acute CL reduction (produced by flash-induced Ca2+ release from a caged Ca2+ buffer), which we had reported previously. Three contemporary numerical models (including the original Maltsev-Lakatta model) failed to reproduce the experimental results. In our proposed new model, Ca2+ releases acutely change the CL via activation of the Na+/Ca2+ exchanger current. Time-dependent CL reductions after flash-induced Ca2+ releases (the memory effect) are linked to changes in Ca2+ available for pumping into sarcoplasmic reticulum which, in turn, changes the sarcoplasmic reticulum Ca2+ load, diastolic Ca2+ releases, and Na+/Ca2+ exchanger current. These results support the idea that Ca2+ regulates CL in cardiac pacemaker cells on a beat-to-beat basis, and suggest a more realistic numerical mechanism of this regulation.
Optical Pumping of Helium in the S 1 3 Metastable State

The alignment of ${\mathrm{He}}^{4}$ atoms in the ($n=2$, metastable) $^{3}S_{1}$ state is described. Metastable atoms are produced by an rf discharge in a glass tube containing a few mm of pure helium, and the one micron pumping light ($2^{3}P\ensuremath{-}2^{3}S$) is provided by a helium lamp. A resonance signal is obtained from radio frequency disorientation by monitoring the transmitted pumping light. The double maximum line shape of this signal for strong rf magnetic fields is discussed. Included also is a discussion of the angular dependence of the signal when unpolarized light is used and an explanation of the inversion of the resonance signal for certain densities of the metastable helium atoms.The measured relaxation time of the oriented metastable atoms in the discharge is about 2.5\ifmmode\times\else\texttimes\fi{}${10}^{\ensuremath{-}4}$ second and the pumping time is about a millisecond. A method is proposed and initial measurements are given for the cross section for destruction of metastable helium atoms by collision with foreign gas atoms. The application of optical pumping in helium to the measurement of weak magnetic fields is also discussed.
Mapping GFP structure evolution during proton transfer with femtosecond Raman spectroscopy

GFP, the green fluorescent protein from the jellyfish Aequorea victoria, is widely used in the life sciences as a gene expression marker because of its efficient bioluminescence. The atomistic details of the excited-state proton transfer that generates this bioluminescence are still not fully understood. Fang et al. have used femtosecond stimulated Raman spectroscopy of the GFP chromophore to obtain detailed time-resolved vibrational spectra that reveal how a low-frequency skeletal vibration poises the protein for the critical proton transfer process. As well as throwing light on a reaction central to countless biological studies, this method of making real-time observations of the structural changes of a molecule during a multidimensional chemical reaction should have broad application in the determination of reaction mechanisms. Tracing the transient atomic motions that lie at the heart of chemical reactions requires high-resolution structural information on the timescale of molecular vibrations. Femtosecond stimulated Raman spectroscopy is now shown to provide sufficiently detailed and time-resolved vibrational spectra of the electronically excited chromophore of green fluorescent protein to reveal skeletal motions involved in the proton transfer that produces the fluorescent form of the protein. Tracing the transient atomic motions that lie at the heart of chemical reactions requires high-resolution multidimensional structural information on the timescale of molecular vibrations, which commonly range from 10 fs to 1 ps. For simple chemical systems, it has been possible to map out in considerable detail the reactive potential-energy surfaces describing atomic motions and resultant reaction dynamics1, but such studies remain challenging for complex chemical and biological transformations2. A case in point is the green fluorescent protein (GFP)3,4,5 from the jellyfish Aequorea victoria, which is a widely used gene expression marker owing to its efficient bioluminescence. This feature is known to arise from excited-state proton transfer (ESPT)6,7,8, yet the atomistic details of the process are still not fully understood. Here we show that femtosecond stimulated Raman spectroscopy9,10 provides sufficiently detailed and time-resolved vibrational spectra of the electronically excited chromophore of GFP to reveal skeletal motions involved in the proton transfer that produces the fluorescent form of the protein. In particular, we observe that the frequencies and intensities of two marker bands, the C–O and C = N stretching modes at opposite ends of the conjugated chromophore, oscillate out of phase with a period of 280 fs; we attribute these oscillations to impulsively excited low-frequency phenoxyl-ring motions, which optimize the geometry of the chromophore for ESPT. Our findings illustrate that femtosecond simulated Raman spectroscopy is a powerful approach to revealing the real-time nuclear dynamics that make up a multidimensional polyatomic reaction coordinate.
Intracardiac lead endocarditis due to Staphylococcus lugdunensis

Staphylococcus Lugdunensis is a rare but potentially aggressive pathogen in the family of coagulase negative staphylococcus (CoNS). It can cause a wide variety of infections ranging from superficial skin to fulminant infections like endocarditis. Both native and prosthetic valve endocarditis due to S. lugdunensis have been documented in the English literature. Eight cases of pacemaker lead endocarditis due to S. lugdunensis have been described so far. We present the ninth case of pacemaker lead and first case of automatic implantable cardioverter defibrillator (AICD) lead endocarditis due to S. lugdunensis.
Controls on diel metal cycles in a biologically productive carbonate-dominated river

Abstract The 24-hour cycle in solar radiation and subsequent primary productivity by submerged vegetation controls the diel cycles of trace metal concentrations in streams directly, via photochemical reactions and autotrophic assimilation, and indirectly through changes in mineral saturation states, redox conditions, and adsorption reactions. Most prior studies have focused on streams with elevated metal concentrations and thus cycling is not as well understood in pristine streams where the effects of submerged plant metabolism may be critical in controlling the availability and diel cycling of metals. To assess controls on diel metal cycling in an alkaline river with naturally low metal concentrations, water samples were collected every 1–2 h for > 24 hours in three seasons between March 2009 and May 2010 in the Ichetucknee River, north-central Florida (USA), a large (Q > 6 m 3 /s), spring-fed river flowing over a carbonate karst terrain. Ca 2 + , Ba, Fe, and U concentrations exhibit statistically significant diel cycles regardless of season, while Mn, and possibly Sr, cycles were present only in the spring. Mn, Ba and Ca 2 + concentrations increased at night, out of phase with the cycles in pH and carbonate saturation state. Daytime precipitation of calcium carbonate could partially control Mn, and to a lesser extent Ba, cycles through co-precipitation. Fe and U concentrations cycled in phase with solar radiation, pH, and DO concentrations, reaching maxima in late afternoon. Adsorption of cationic Mn and Ba species and anionic U and Fe species could explain the opposing cycles of these two sets of metals as could the photo-reduction of Fe, enhanced by the high water clarity. The diel cycles of Mn, Fe and Ba also appear to be directly controlled by autotrophic assimilation based on estimates of net carbon fixation by submerged vegetation and the metal stoichiometry of the dominant submerged macrophyte and algae in the river. These results demonstrate how multiple biogeochemical processes resulting from solar radiation and associated aquatic plant metabolism likely control diel and seasonal cycles of metals and illustrate the importance of these linked processes in mediating the water quality and environmental availability of metals in pristine streams with naturally low metal concentrations.
English learners left behind: standardized testing as language policy

English learners left behind: standardized testing as language policy, by K. Menken, Clevedon, Multilingual Matters, 2008, v + 207 pp., US$99.85 (hardback), ISBN 978-1-85359-998-9; US$39.95 (paperb...
Interaction of Diabetes and Hypertension on Determinants of Endothelial Adhesiveness

Abstract—Epidemiological studies have established that diabetes mellitus and hypertension are independent risk factors for atherosclerosis. One of the earliest abnormalities seen in atherogenesis is enhanced monocyte adherence to the endothelium. The mechanisms by which diabetes mellitus or hypertension enhances monocyte–endothelial cell interactions are incompletely characterized. It is not known whether there are additive interactions between these risk factors on endothelial adhesiveness for monocytes. Male Wistar-Kyoto (WKY) and spontaneously hypertensive (SHR) rats were fed a normal or fructose-enriched diet. In some cases, animals were injected with streptozotocin (35 mg/kg body weight) to induce diabetes. After 2 weeks, plasma was drawn for biochemical measurements, and thoracic aortas were harvested, opened longitudinally, and exposed to fluorescently labeled mouse monocytoid cells (WEHI 78/24, 2×106/mL) for 30 minutes on a rocking platform. Adherent cells were counted by epifluorescence microscop...
Leucémies à tricholeucocytes révélées par des manifestations articulaires

Resume La leucemie a tricholeucocytes est un syndrome lymphoproliferatif B chronique rare de l’adulte evoque devant une splenomegalie, une pancytopenie et une diminution caracteristique des monocytes. Le diagnostic est confirme devant la presence dans le sang ou la moelle de cellules a « cheveux » CD19+ CD20+ CD25+ CD11c+. La leucemie a tricholeucocytes est dans de rares cas revelee par des arthrites. Ces atteintes articulaires sont rapportees soit a la leucemie a tricholeucocytes, soit a des pathologies dysimmunitaire. C’est ainsi que la polyarthrite rhumatoide realise parfois des tableaux polymorphes susceptibles d’egarer le diagnostic. La monocytopenie est un element fondamental d’orientation. La decouverte de cellules tricholeucocytaires dans le liquide articulaire confirme l’arthrite leucemique. Le traitement repose sur les analogues des purines. L’un des principaux diagnostics differentiels est le syndrome de Felty associant polyarthrite rhumatoide, neutropenie et splenomegalie et correspondant le plus souvent a un syndrome lymphoproliferatif T. Nous rapportons sur une serie de 27 cas, un cas de leucemie a tricholeucocytes revele par des manifestations articulaires.
Study of τ Decays to Four-Hadron Final States with Kaons

The rare τ lepton decays to four explicitly identified hadrons have been studied with the CLEO detector at the Cornell Electron Storage Ring (CESR) using ( 7.56 ± 0.15 ) fb −1 of data collected near s = 10.58 GeV . The first statistically significant measurements of B ( τ − → K − π + π − π 0 ν τ , excluding K 0 ) = ( 7.4 ± 0.8 ± 1.1 ) × 10 −4 and B ( τ − → K − K + π − π 0 ν τ ) = ( 5.5 ± 1.4 ± 1.2 ) × 10 −5 are presented, including the first observation of the decay τ −1 → K − ω ν τ with branching fraction, ( 4.1 ± 0.6 ± 0.7 ) × 10 −4 . We also publish the first upper limit for B ( τ − → K − K + K − π 0 ν τ ) 4.8 ( 6.1 ) × 10 −6 at 90% (95%) confidence level (C.L.). We also measure for the first time the invariant mass distributions of the decays.
The Knee Nook

AbstractAlthough the effects of a stroke vary, survivors often have limited use of one side of their body. Stroke survivors may wear an ankle-foot orthosis (AFO) to prevent their weak foot from dragging and hindering ambulation. Because of the added bulk of an AFO, donning a shoe becomes difficult. The design team, composed of freshman engineering students in the Engineering Design and Communication course at Northwestern University, interviewed stroke survivors to understand the problem and then constructed several prototypes as possible solutions. After stroke survivors tested and critiqued each prototype, the Knee Nook emerged as the most promising. Stroke survivors often place their weak foot on top of their strong knee, similar to the position of crossing one’s legs, to allow them to easily reach their foot. Keeping the weak leg in place on the strong thigh while donning the AFO is often difficult. The Knee Nook is a hands-free device that holds the user’s leg in this position. The device is placed o...
A study and model of the role of the Renshaw cell in regulating the transient firing rate of the motoneuron

This study sought to investigate the role of the Renshaw cell with respect to transient motoneuron firing. By studying the cat motoneuron and Renshaw cell, several low-order lumped parameter models were developed that simulate the known characteristics of the injected input current vs. firing rate. The neuron models in the Renshaw cell inhibition configuration were tuned to fit experimental data from cat motoneurons. Models included both linear versions and those with sigmoidal nonlinearities. Results of the simulation indicate that the motoneuron itself provides the adaptation seen in its firing rate and that the Renshaw cell's role is primarily to fine-tune the motoneuron's adaptation process.
Properties of the bound states of super Yang-Mills-Chern-Simons theory

We apply supersymmetric discrete light-cone quantization (SDLCQ) to the study of supersymmetric Yang-Mills\char21{}Chern-Simons (SYM-CS) theory on $\mathbf{R}\ifmmode\times\else\texttimes\fi{}{S}^{1}\ifmmode\times\else\texttimes\fi{}{S}^{1}.$ One of the compact directions is chosen to be lightlike and the other to be spacelike. Since the SDLCQ regularization explicitly preserves supersymmetry, this theory is totally finite, and thus we can solve for bound-state wave functions and masses numerically without renormalizing. The Chern-Simons term is introduced here to provide masses for the particles while remaining totally within a supersymmetric context. We examine the free, weak and strong-coupling spectrum. The transverse direction is discussed as a model for universal extra dimensions in the gauge sector. The wave functions are used to calculate the structure functions of the lowest mass states. We discuss the properties of Kaluza-Klein states and focus on how they appear at strong coupling. We also discuss a set of anomalously light states which are reflections of the exact Bogomol'nyi-Prasad-Sommerfield states of the underlying SYM theory.
Bacterial histone-like proteins: roles in stress resistance

Histone-like proteins (HLPs) are small and basic bacterial proteins that are associated with a nucleoid and play roles in maintaining DNA architecture and regulating DNA transactions such as replication, recombination/repair and transcription. The studies on HLPs from a variety of bacterial species in recent years are summarized in this mini-review. A recent study reported a novel DNA-binding protein (HP119) in Helicobacter pylori that shows some HLP features. It plays a large role in aiding bacterial stress resistance. We provide herein additional evidence that HP119 is a nucleoid-associated protein, and present some perspectives for future study.
Options for Prevention of HIV Transmission from Mother to Child, with a Focus on Developing Countries

Use of antiretroviral drugs among HIV-infected pregnant women in many developed countries has significantly reduced rates of mother-to-child HIV transmission, demonstrating that this route of transmission is amenable to intervention. Prevention of transmission in developing countries has proved to be more difficult, although recent advances in short-course antiretroviral drug interventions have made it an immediate possibility, rather than a distant hope as it was seen to be in the recent past. Non-antiretroviral drug interventions, including washing of the birth canal with antiseptic solution and micronutrient supplementation, have not been found to be effective at interrupting mother-to-child HIV transmission, but may have other benefits for maternal and child health. An important issue for developing countries is prevention of postnatal HIV transmission through breast feeding. In most developing countries, formula feeding is not a reasonable option, given the higher rates of mortality from diarrheal and respiratory disease associated with avoidance of all breast feeding. A promising new line of research has recently been broached with the findings from a study in South Africa, which demonstrated that exclusive breast feeding is associated with a significant reduction in postnatal transmission of HIV.