cssi/SciSciGPT-SciSciNet huggingface dataset:
Philosophy of Ecology

Although philosophy of ecology was slow to become established as an area of formal philosophical interest, there is a rich history of developing and debating conceptual frameworks in ecological and environmental science. A key challenge in conceptualising ecological complexity is to allow simultaneously for particularity, contingency and structure – structure, moreover, that changes, is internally differentiated, and has problematic boundaries. In contrast to ambitions of earlier decades for identifying general principles about systems and communities, ecologists now widely assert historical contingency, nonequilibrium formulations, local context and individual detail. Given that all organisms – humans included – live in dynamic ecological contexts, philosophy of ecology raises more general questions about conceptualising the positionality of humans and other organisms in the dynamic flux of their intersecting worlds. Key Concepts: Although philosophy of ecology was slow to become established as an area of formal philosophical interest, there is a rich history of developing and debating conceptual frameworks in ecological and environmental science. A challenge faced by all ecologists is to deal with ongoing change in the structure of situations that have built up over time from heterogeneous components and are embedded or situated within wider dynamics. All organisms live in an ecological context that has structure and dynamics, so all philosophy of biology depends on some implicit conceptualization of ecological relations. Ecologists of a particularistic bent question many of community ecology's models, rejecting them when their fit to data was no better than alternative ‘null’ hypotheses or ‘random’ models. Observation and experiment can contribute to the generation of theory in many ways other than through crucial hypothesis tests. Models need not be seen simply as representations intended to capture the necessary and sufficient conditions to explain observed phenomena – exploration of models can produce new concepts, questions and hypotheses. In contrast to ambitions of earlier decades for identifying general principles about systems and communities, ecologists now widely assert historical contingency, nonequilibrium formulations, local context and individual details. Under the label ‘political ecology’, environmental problems can be analysed in terms of intersecting economic, social and ecological processes, which operate across various spatial and temporal scales and are mutually implicated in the production of any outcome and in their own ongoing transformation. Self-consciousness about the social interactions involved in producing ecological knowledge extends a post-modernist critique of unified science that argues that people's reasonings can only be rooted in historically specific life practices. Keywords: complexity; models; history; scale; boundaries
Persistent human immunodeficiency virus type 1 infection of monoblastoid cells leads to accumulation of self-integrated viral DNA and to production of defective virions.

Abstract Cell-free virus preparations from persistently infected monoblastoid cells (HU937) become progressively less infectious during long-term passage. This effect is specific for cell lines derived from U937 and is not observed in persistently infected T-cell lines. Reduced infectivity is correlated with accumulation of unusual, high-molecular-weight, extrachromosomal forms of the human immunodeficiency virus type 1 (HIV-1) DNA. These DNA molecules contain multiple copies of the viral genome, and their structures are highly variable. Of 17 subclones of the HU937 cell line, 15 unique restriction fragment patterns were observed for the HIV-1 viral DNA. Structural analysis of these viral DNA species indicated that they were formed by sequential rounds of long terminal repeat-mediated integration of one circular DNA form into preexisting monomeric or multimeric structures. These viral DNA structures are termed nested self-integrates. Once formed, self-integrates prove to be stable and can be maintained for several months in culture. The unusual structures of HIV-1 DNA in persistently infected monoblastoid cells attest to an alternative to the accepted retrovirus life cycle. The self-integrated viral DNA species reported here may explain some aspects of the mechanism controlling establishment and maintenance of persistent HIV-1 infection in cells of the monocyte/macrophage lineage.
The Role of Vaccines for HPV-Related Head and Neck Cancers

Several lines of evidence highlight the importance of a functioning immune system in controlling human papillomavirus (HPV) infection and its associated neoplasms. Harnessing the immune system to both prevent and treat HPV infections has therefore been an area of significant research effort, innovation and progress over the past decades. Although much of the research performed thus far has been on genital HPV infections, the interaction between oral HPV infection and the immune system are beginning to be explored.
CVs in Globular Clusters: Clues to Compact Binary Production

Cataclysmic variables (CVs) ought to be the most numerous compact binaries in globular clusters, given standard theories for their formation by capture or exchange and the large excess of white dwarfs over neutron stars expected in globulars. Yet their numbers thus far detected are vastly surpassed by the numbers of either Low Mass X-ray Binaries (LMXBs) or their possible successors, millisecond pulsars (MSPs). Where are the cluster CVs? Here we briefly describe both the previous detections and limits, the ongoing searches and several observations of LMXBs which may relate to the cluster CV enigma.
“Pinning” of Transition-Metal Impurity Levels

This summary abstract reviews the conclusions of recent work by Tersoff and Harrison,1 using the defect-molecule approach of Picoli, Chomette and Lannoo.2 For a more detailed presentation, the reader is referred to Ref. 1, and to references therein.
Global Capital Markets: Global Capital Markets: Overview and Origins

At the turn of the twenty-first century, the merits of international financial integration are under more forceful attack than at any time since the 1940s. Even mainstream academic proponents of free multilateral commodity trade, such as Jagdish Bhagwati, argue that the risks of global financial integration outweigh the benefits. Critics from the left such as Lord Eatwell, more wary even of the case for free trade on current account, claim that since the 1960s “free international capital flows” have been “associated with a deterioration in economic efficiency (as measured by growth and unemployment).” Such a resurgence of concerns about international financial integration is understandable in light of the multiple crises seen since the early 1990s in Western Europe, Latin America, East Asia, Russia, and elsewhere. Supporters of free trade in tangible goods have long recognized that its net benefits to countries typically are distributed unevenly, creating domestic winners and losers. Recent international financial crises, however, have submerged entire economies and threatened their trading partners, inflicting losses all around. International financial transactions rely inherently on the expectation that counterparties will fulfill future contractual commitments; they therefore place confidence and possibly volatile expectations at center stage. These same factors are present in purely intranational financial trades, of course, but the relatively higher costs of trading goods and assets internationally make the adjustments to market shocks more costly. Furthermore, problems of oversight, adjudication, and enforcement all are orders of magnitude more difficult among sovereign nations with distinct national currencies than within a single national jurisdiction. And because there exists no natural world lender of last resort, international crises are intrinsically harder to head off and contain than are purely domestic ones.
A double-mimetic peptide efficiently neutralizes HIV-1 by bridging the CD4- and coreceptor-binding sites of gp120

ABSTRACT The HIV-1 envelope glycoprotein binds cooperatively to its cellular receptor CD4 and a coreceptor, principally CXCR4 or CCR5. We have previously improved a natural amino-acid form of a scorpion toxin-derived CD4-mimetic peptide and in parallel generated sulfopeptide mimetics of the CCR5 amino terminus. Here we show that some fusions of these CCR5- and CD4-mimetic peptides, expressed as immunoadhesins, neutralize HIV-1 more efficiently than CD4-Fc or equimolar mixtures of immunoadhesin forms of each peptide. Specifically, double-mimetic peptides with linkers of 11 amino acids or greater, and with the CCR5-mimetic component preceding the CD4-mimetic component, were more efficient than constructs with shorter linkers or in a reverse orientation. The potency of these constructs derives from (i) their ability to simultaneously and cooperatively bind the CD4- and CCR5-binding sites of a single gp120 monomer of the HIV-1 envelope glycoprotein trimer and (ii) the ability of the CCR5-mimetic component to prevent the CD4-mimetic peptide from promoting infection when cellular CD4 is limiting. Thus, there is a significant advantage to simultaneously targeting both conserved regions of the HIV-1 envelope glycoprotein. IMPORTANCE This report describes a novel class of peptides that potently inhibit HIV-1 entry. These peptides simultaneously target the receptor- and coreceptor-binding sites of the HIV-1 envelope glycoprotein gp120. Peptides of this class overcome key limitations of inhibitors that target only one gp120 binding region and illustrate the utility of binding the sulfotyrosine-binding pockets of gp120.
Healthy worker survivor bias: implications of truncating follow-up at employment termination.

Objectives The healthy worker survivor effect is a bias that occurs in occupational studies when less healthy workers are more likely to reduce their workplace exposures. When variables on the pathway from health status to exposure are measured, g-methods can avoid this bias. However, studies in which follow-up ends at employment termination have additional potential for selection bias. This paper examines the structure of the healthy worker survivor effect, compares results with and without censoring at employment termination, and addresses how to prevent bias when such censoring occurs. Methods G-estimation of structural accelerated failure time models was applied in the United Autoworkers— General Motors cohort study to examine relationships between metalworking fluid exposure and cause-specific mortality. Subjects were followed from hire through 1994, regardless of employment status. To answer the central question, g-estimation analysis was repeated after truncating at employment termination and censoring outcomes that occurred thereafter, with adjustment for censoring by inverse probability weighting. Results Using full follow-up time, HRs were estimated for all-cause mortality (1.09), ischaemic heart disease death (1.19), and death from any cancer (1.09), comparing 5 years of metalworking fluid exposure to no exposure. For all three outcomes, the HR estimates based on data censored at termination of employment were below 1 (respectively, 0.92, 0.97, 0.79). Conclusions In this application, g-estimation together with weighting did not prevent selection bias due to employment termination. However, the bias might be avoided in studies with measured health-related variables on the pathway from health status to employment termination.
Evaluation of Tobramycin in Severe Urinary Tract Infection

Tobramycin sulfate is a bactericidal aminoglycoside antibiotic which in animal studies has been shown to have lower acute toxicity and lower nephrotoxicity than gentamicin (1,2). Tobramycin has been shown to have more activity in vitro against Pseudomonas sp. than other aminoglycoside antibiotics (3,4). Tobramycin is excreted unchanged in the urine and assayable blood levels are present for at least eight hours. Studies in patients with renal failure showed that the serum half-life was directly related to the degree of renal impairment and that reduced doses were necessary. This antibiotic was found to be effective against infections due to susceptible organisms in the genitourinary system- Pseudomonas sp., Esch. coli, the Klebsiella-Enterobacter-Serratia group, indole-positive and indole-negative Proteus sp., staphylococci and group D streptococci. Early clinical studies showed that Tobramycin was successful in eradicating infections with Pseudomonas sp. which had prior unsuccessful therapy with gentamicin and/or carbenicillin.
Evaluation of the Accuracy and Precision of Volunteered Size Data from Tagged Red Drum Returns

Abstract The accuracy and precision of total lengths and weights from recaptured tagged red drum (Sciaenops ocellatus) reported by Texas Parks and Wildlife Department (TPWD) biologists, anglers, and commercial fishermen were compared. No differences were found in the total length-weight regressions of data reported by sport and commercial fishermen, but there were significant differences found between data reported by fishermen and data collected by TPWD biologists (F, = 6.312; P < 0.05). Fish lengths reported by fishermen were not biased but they were more variable than lengths reported by TPWD due to rounding to the nearest whole or partial English unit. Weights reported by fishermen were more variable than weights reported by TPWD biologists. A significant difference between regression coefficients was found and a comparison of confidence limits of the regression lines showed that fishermen overestimated the weight of small fish; therefore, growth estimates calculated from red drum weights provided by ...
Do the risks of predation and intermale competition affect courtship behavior in the salamander Desmognathus ochrophaeus

Natural populations of mountain dusky salamanders, Desmognathus ochrophaeus (Amphibia: Caudata: Plethodontidae), may experience two types of risk during courtship encounters: interspecific predation, affecting both sexes, and intraspecific competition for mates, affecting males. We conducted two experiments in the laboratory to determine whether and how these two risks influence the outcome of male-female encounters. In experiment 1, courtship interactions resulting in spermatophore deposition were inhibited in the presence of a restrained species of salamander (Gyrinophilus porphyriticus) known to prey on D. ochrophaeus. Probability of successful courtship was not affected by the presence of a restrained species that is not predatory (Plethodon teyahalee). In experiment 2, courtship interactions resulting in spermatophore deposition were inhibited in the presence of two restrained conspecific males, but were unaffected in the presence of a single restrained male. We conclude that the dual risks of predation and intrasexual competition for mates have been significant selective factors in shaping the evolution of courtship decisions in Desmognathus ochrophaeus.
Implementation of a Si/SiC hybrid optically controlled high-power switching device

The ever-increasing performance and economic requirements placed on commercial and military aircraft are resulting in the need for very complex avionic systems. To help alleviate some of the design complexity, fiber optic components have been suggested as an enabling technology that could allow the creation of an optical communications network routed throughout the avionic systems of an aircraft. Based on the often-cited benefits of high data throughput, immunity to EMI, reduced maintenance costs and reduced weight, the use of fiber optic links to communicate control signals and sensor information throughout the aircraft could lead to significant performance improvements for next generation aircraft. Fly-by-Light systems that use optical control signals to actuate the flight surfaces of an aircraft have been suggested as an important technology for avionic systems where degradation of signal integrity due to EMI can have catastrophic consequences. Current fly-by-light systems are limited by the lack of optically activated high-power switching devices. The challenge has been the development of an optoelectronic switching technology that can withstand the high power and harsh environmental conditions common in a flight surface actuation system. Wide bandgap semiconductors such as Silicon Carbide offer the potential to overcome both the temperature and voltage blocking limitations that inhibit the use of Silicon. Unfortunately, SiC is not optically active at the near IR wavelengths where communications grade light sources are readily available. Thus, we have proposed a hybrid device that combines a silicon based photoreceiver module with a SiC power transistor. When illuminated with a 5mW optical control signal the silicon chip produces a 15 mA drive current for a SiC Darlington pair. The SiC Darlington pair then produces a 150 A current that is suitable for driving an electric motor with sufficient horsepower to actuate the control surfaces on an aircraft. Further, when the optical signal is turned off, the SiC is capable of holding off a 270 V potential to insure that the motor drive current is completely off. We present in this paper the design and initial test results from a prototype device that has recently been fabricated.
Synthesis of 1,2-Diethyl-4-(2-hydroxyethyl)pyrazolidine

The reaction of 1,2-diethythydrazine with monomethyl itaconate has been investigated and found to give a mixture of 1,2-diethyl-4-carbomethoxymethyl-3-pyrazol-idinone and its hydrolysis product, the corresponding acid. Reduction of either the ester or the acid affords 1,2-diethyI-4-(2-hydroxyethyl)pyratolidine.
Modeling an electronic throttle controller using the timed abstract state machine language and toolset

In this paper, we present an integrated toolset that implements the features of the Timed Abstract State Machine (TASM) language, a novel specification language for embedded real-time systems. The toolset enables the creation of executable specifications with well-defined execution semantics, abstraction mechanisms, and composition semantics. The features of the toolset are demonstrated using an Electronic Throttle Controller (ETC) from a major automotive vendor. The TASM toolset is used to analyze the resource consumption resulting from the mode switching logic of the ETC, and to verify the completeness and consistency of the specification.
Conduction of the effects of noxious stimulation by short-fiber multisynaptic systems of the spinal cord in the rat.

Abstract To evaluate the contribution of spinal cord, short-fiber, multisynaptic systems in the mediation of pain, rats underwent two-stage, spaced hemisections on both sides of the cord. The surgery was intended to section all long-fiber tracts and to isolate a short-fiber system. Prior to operation, the rats were trained to perform a head-turning response in order to terminate noxious electric shock applied to one hind-limb. The rats then underwent a high, thoracic hemisection, contralateral to the shocked foot. On retesting, only slight increased latency changes were evident. A second hemisection, contralateral and caudal to the first lesion, produced a marked increase in threshold and latency, but the escape response was never abolished. Vocalization to the shock disappeared permanently, provided that all of the ventral funiculus was cut. In order to transfer the direction of the head-turning response, shock intensities had to be further increased and latencies rose again. One rat underwent both hemisections prior to learning the escape response. Prolonged training at high shock intensities established the response postoperatively. Spinal transection caudal to both hemisections abolished the escape response, thus eliminating extraspinal systems or current spread as an explanation for maintained responding in the absence of long-fiber tracts of the cord. It was concluded that a short-fiber multisynaptic system is sufficient for conveying the effects of noxious stimulation. Section of the crossed spinothalamic or “pain” tract produces only minor changes; however, the marked differences between normal and double-hemisected rats suggests that other long-fiber tracts interact with short-fiber systems in the mediation of pain in the intact rat.
Nonuniformly Communicating Noncontiguous Data: A Case Study with PETSc and MPI

Due to the complexity associated with developing parallel applications, scientists and engineers rely on high-level software libraries such as PETSc, ScaLAPACK and PESSL to ease this task. Such libraries assist developers by providing abstractions for mathematical operations, data representation and management of parallel layouts of the data, while internally using communication libraries such as MPI and PVM. With high-level libraries managing data layout and communication internally, it can be expected that they organize application data suitably for performing the library operations optimally. However, this places additional overhead on the underlying communication library by making the data layout noncontiguous in memory and communication volumes (data transferred by a process to each of the other processes) nonuniform. In this paper, we analyze the overheads associated with these two aspects (noncontiguous data layouts and nonuniform communication volumes) in the context of the PETSc software toolkit over the MPI communication library. We describe the issues with the current approaches used by MPICH2 (an implementation of MPI), propose different approaches to handle these issues and evaluate these approaches with micro-benchmarks as well as an application over the PETSc software library. Our experimental results demonstrate close to an order of magnitude improvement in the performance of a 3-D Laplacian multi-grid solver application when evaluated on a 128 processor cluster.
Utilization of chopped and long alfalfa by dairy heifers.

Two physical forms of alfalfa hay, chopped and long, were fed at maintenance and for ad libitum consumption to dairy heifers to determine effects upon digestibility and energy utilization. Ad libitum intake was associated with lower digestibility of dry matter (56 versus 58%), neutral detergent fiber (45 versus 58%), and acid detergent fiber (45 versus 52%). Energy balance was 1.77 Mcal/day at ad libitum versus .08 Mcal/day at maintenance. Dry matter intake was similar for chopped (5.4 kg/day) versus long alfalfa (5.5 kg/day). Digestibilities of dry matter, neutral detergent fiber, acid detergent fiber, and cellulose were 7 to 10 percentage units lower when heifers were fed the chopped alfalfa. Metabolizable energy intake generally reflected digestible energy intake, which was about 2 Mcal/day less for heifers consuming chopped alfalfa. Heat production was similar for the two physical forms. Consequently, heifers consuming chopped alfalfa had lower energy balance. Reducing particle size of the alfalfa resulted in lower dry matter and energy digestibility, presumably because of increased rate of passage. Increased intake to compensate for depressed energy utilization of the chopped alfalfa did not occur; effects upon animal gain could not be assessed.
Self-referenced Erbium fiber laser frequency comb at a GHz repetition rate

An Erbium fiber laser frequency comb operating at a GHz repetition rate is reported. The f ceo and f rep stabilized all-fiber system produces 2nJ sub-100fs pulses to seed octave-spanning supercontinuum generation spanning 1μm-2.4μm.
Role of spatial correlation in photon-counting integral imaging

The method of photon-counting integral imaging (PCII) has been introduced recently for three-dimensional object sensing, visualization, recognition and classification of scenes under photon-starved conditions. This paper presents an information-theoretic model for the PCII method, thereby providing a rigorous foundation for our understanding of its demonstrated success in compressive imaging and classification.
Localization of β-glycerophosphatase activity in cotton fiber during differentiation

The distribution of β-glycerophosphatase activity in the outer integument of cotton (Gossypium hirsutum L.) ovules was determined histochemically at the electron microscope level. Both a linted cultivar and a lintless mutant line were examined from 1 day preanthesis to 3 days postanthesis. No enzyme activity was observed in the lintless line at any stage. In the linted cultivar there was no enzyme activity before anthesis, but as fibers were initiated on the day of anthesis, activity was observed in the expanding fiber cell wall and nucleus. As the fibers started elongating, enzyme activity was particularly concentrated in the cytoplasm and wall where directional growth towards the micropyle occurs. By 2 days postanthesis, β-glycerophosphatase activity was decreasing in the cell wall and nucleus, but was increasing in the nucleolus. Enzyme activity in the nucleolus was highest at 3 days post-anthesis, but nuclear β-glycerophosphatase activity was not observed then. These results indicate that β-glycerophosphatase activity was associated with differentiating fiber cells, specifically with those sites where distinct anatomical, and perhaps catabolic, changes were occurring. The significance of the results is discussed in relation to possible mechanisms of cotton fiber differentiation.
The joint action of nitrogen and nematicides on Pratylenchus penetrans and potato yield

The joint action of nitrogen fertilizer and nematicides onPratylenchus penetrons and yield was investigated using three potato varieties (Superior, Onaway and Russet Burbank), three rates of nitrogen (84, 168 and 336 kg/ha), five edaphic pesticides (disulfoton, aldicarb, 1,3-D + MIC, carbofuran and thiofanox), and an insecticide spray to minimize the role of foliar feeding insects
The Role of Nitric Oxide in Coronary Vascular Effects of Estrogen in Postmenopausal Women

Background At physiological concentrations, 17β-estradiol selectively enhances endothelium-dependent coronary vasodilation by an unknown mechanism in postmenopausal women. Methods and Results To assess the contribution of nitric oxide (NO) to the vascular effects of estradiol, we measured coronary epicardial and microvascular responses to intracoronary acetylcholine (range, 3 to 300 μg/min for 2 minutes) before and after intracoronary estradiol 75 ng/min for 15 minutes in 20 estrogen-deficient women, 16 of whom had angiographic evidence of atherosclerosis or risk factors for atherosclerosis. This testing was repeated after inhibition of NO synthesis with intracoronary N G-monomethyl-l-arginine (L-NMMA) 64 μmol/min for 5 minutes. Estradiol increased acetylcholine-stimulated coronary flow from 54±48% (mean±SD) above baseline values before estradiol infusion to 100±63% above baseline values ( P =.007) and decreased coronary resistance from 32±21% to 46±15% below baseline values ( P =.007) at a coronary sinus estradiol concentration of 1725±705 pmol/L (470±192 pg/mL). Estradiol also tended to lessen the severity of acetylcholine-induced epicardial coronary artery vasoconstriction from 8±11% to 3±11% below baseline values ( P =.123). However, during L-NMMA infusion, estradiol no longer potentiated the effects of acetylcholine on coronary flow dynamics; coronary flow increased 39±46% above baseline values and coronary resistance decreased 19±30% below baseline values (both P <.001 versus pre–L-NMMA responses). The epicardial diameter decreased 8±11% below baseline values ( P =.06 versus pre–L-NMMA response). Conclusions The effects of estradiol at physiological concentrations on endothelium-dependent coronary vasodilator responsiveness in postmenopausal women are mediated by enhanced bioavailability of NO, which may be responsible in part for the cardioprotective effects of estrogen.
Influence of Biomacromolecules and Humic Acid on the Aggregation Kinetics of Single-Walled Carbon Nanotubes

The initial aggregation kinetics of single-walled carbon nanotubes (SWNTs) were studied using time-resolved dynamic light scattering. Aggregation of SWNTs was evaluated in the presence of natural organic matter [Suwannee River humic acid (SRHA)], polysaccharide (alginate), protein [bovine serum albumin (BSA)], and cell culture medium [Luria-Bertani (LB) broth] with varying solution concentrations of monovalent (NaCl) and divalent (CaCl(2)) salts. Increasing salt concentration and adding divalent calcium ions induced SWNT aggregation by screening electrostatic charge and thereby suppressing electrostatic repulsion, similar to observations with aquatic colloidal particles. The presence of biomacromolecules significantly retarded the SWNT aggregation rate. BSA protein molecules were most effective in reducing the rate of aggregation followed by SRHA, LB, and alginate. The slowing of the SWNT aggregation rate in the presence of the biomacromolecules and SRHA can be attributed to steric repulsion originating from the adsorbed macromolecular layer. The remarkably enhanced SWNT stability in the presence of BSA, compared to that with the other biomacromolecules and SRHA, is ascribed to the BSA globular molecular structure that enhances steric repulsion. The results have direct implications for the fate and behavior of SWNTs in aquatic environments and biological media.
Limiting factors in plant residues of low biodegradability

Abstract The resistances of low quality plant residues to anaerobic digestion are related to the high content of total structural matter and its intrinsic physicochemical characteristics. Natural factors include lignin, tannins and biogenic silica, while processing and storing further reduce quality through non-enzymatic browning reactions, and changes in particle size and physical surface properties. Delignified materials may exhibit greater lag and lower rates of digestion. Exchange capacity is much reduced in treated materials. Individually plant residues vary in the nature of their principal limiting factors. Silica is the primary factor in rice straw and lignin in most other crop residues. The effect of lignin depends on covalent linkage with structural carbohydrate and lignin obligately protects 1.4 times its own weight of carbohydrate in untreated materials. Lignin cleaved by alkali treatment is soluble in neutral detergent as evidence by ultraviolet absorption of neutral detergent extracts. It may lower digestibility of solubles through dilution and tanning reactions. The efficiency of alkali treatment of graminaceous straws can be assayed by the measurement of saponifiable groups within the residual structural matter.
Nutrition in elderly hemodialysis patients

The elderly dialysis population is increasing. Current nutritional recommendations for this group of patients are based on extrapolations of the recommendations for the general well elderly and adult hemodialysis populations. More than 60% of patients receiving renal replacement therapy in the US will be over the age of 65 by the year 2000. This mandates the need for the development of age-specific nutrient recommendations for elderly dialysis patients. This article presents methods for assessing nutritional status and identifying and treating malnutrition in elderly hemodialysis patients, and psychosocial issues affecting their food intake. Protein, energy and vitamin recommendations for the general elderly and adult hemodialysis populations are also reviewed, and questions raised as to their appropriateness in elderly hemodialysis patients.
Flexible reference trace reduction for VM simulations

The unmanageably large size of reference traces has spurred the development of sophisticated trace reduction techniques. In this article we present two new algorithms for trace reduction: Safely Allowed Drop (SAD) and Optimal LRU Reduction (OLR). Both achieve high reduction factors and guarantee exact simulations for common replacement policies and for memories larger than a user-defined threshold. In particular, simulation on OLR-reduced traces is accurate for the LRU replacement algorithm, while simulation on SAD-reduced traces is accurate for the LRU and OPT algorithms. Both policies can easily be modified and extended to maintain timing information, thus allowing for exact simulation of the Working Set and VMIN policies. OLR also satisfies an optimality property: for a given original trace and chosen memory size, it produces the shortest possible reduced trace that has the same LRU behavior as the original for a memory of at least the chosen size. We present a proof of this optimality of OLR, and show that SAD, while not optimal, yields nearly optimal performance in practice.Our approach has multiple applications, especially in simulating virtual memory systems; many page replacement algorithms are similar to LRU in that more recently referenced pages are likely to be resident. For several replacement algorithms in the literature, SAD- and OLR-reduced traces yield exact simulations. For many other algorithms, our trace reduction eliminates information that matters little: we present extensive measurements to show that the error for simulations of the clock and segq (segmented queue) replacement policies (the most common LRU approximations) is under 3p for the vast majority of memory sizes. In nearly all cases, the error is much smaller than that incurred by the well-known stack deletion technique.SAD and OLR have many desirable properties. In practice, they achieve reduction factors up to several orders of magnitude. The reduction translates to both storage savings and simulation speedups. Both techniques require little memory and perform a single forward traversal of the original trace, making them suitable for online trace reduction. Neither requires that the simulator be modified to accept the reduced trace.
An explanation of the anomalous backward enhancement of elastic α-scattering cross sections near A = 40 in terms of an extended optical model

Abstract Elastic α-scattering cross sections for the target nuclei 36Ar, 40Ar, 39K, 41K, 40Ca, 42Ca and 44Ca have been calculated and compared with the data at 24.2 MeV using an extended optical model with an l-dependent absorption. It is shown that the large differences in the experimental cross sections at backward angles for the above nuclei result from different angular momentum mismatches between the elastic and the reaction channels, which in turn are due to the different (α,n) Q-values.
Modeling of zeolite L crystallization using continuum time Monte Carlo simulations

A model to investigate a gel-to-zeolite transformation as a possible growth mechanism through association and rearrangements of extended precursor structures is developed and solved via continuum time lattice Monte Carlo simulations. The model is used to study the morphology of zeolite L nanocrystals grown from an initial amorphous microporous precursor gel. The model considers gel dissolution to release growth precursor extended structures, precursor migration, precursor–precursor association, precursor incorporation into zeolite nanoparticles, and zeolite dissolution. It is shown that the gel-to-zeolite transformation can occur when dissolved precursor migration is slow compared to precursor incorporation and zeolite dissolution. Under these conditions, the initial gel microstructure (intraparticle porosity) has a significant effect on the zeolite morphology and on the crystallization kinetics. This transformation proceeds in two stages: A zeolitic framework forms initially without long-range order, fol...
Lanthanide-anion complexation of a new polyaminopolycarboxylate, DTTAP

Abstract The protonation constants (α's) and the stability constants (K's) of diethylenetriamine-N,N,N′,N″-tetraacetic acid-N″-propionic acid (DTTAP) and its anion-lanthanide complexes, respectively, have been determined experimentally, providing information about the nature of chelation across the lanthanide series. The stability constants indicate that DTTAP can participate in a successful separation of Am from the lanthanides.
Enzyme Assay by Repetitive Flow Injection Analysis. Application to the Assay of Hog Kidney Aminoacylase

Abstract The initial rate of hydrolysis of N-acetylmethionine by hog kidney aminoacylase (EC 3.5.1.14) was determined by repetitive flow injection analysis. The reaction mixture was slowly pumped through an injection valve from which portions were injected into a reagent stream consisting of o-phthaldialdehyde and mercaptoethanol in a borate buffer. This reagent converted the product methionine into a spectrophotometrically-detected isoindole. In a typical assay 15 data points were obtained within the first 22 min of reaction. Initial rates obtained by the method were equal to those obtained by ninhydrin assay.
Formability of sandwich sheet materials in plane strain compression and rolling

The stress states developed during room temperature, plane strain compression modes of deformation of stainless steel clad aluminum and aluminum clad strainless steel sheets have been investigated in order to gain insight into the formability of bonded ductile sandwich sheet materials in primary metalworking processes. Assuming uniform, isostrain deformation in the component layers, sandwich compression stress-strain curves were predicted to be rule of mixtures averages of component compression stress-strain curves. These predictions showed good agreement with experimental data when friction and in-homogeneous deformation were taken into account. Since the through-thickness applied pressure can be assumed to be the same in both components of thin sandwich sheet materials, in-plane stresses which are tensile in the harder component and compressive in the softer component of a clad sheet are developed in order to satisfy the yield conditions. The nature of these in-plane stresses was confirmed by measurements of residual stress distributions in rolled clad sheet specimens, and it was shown how the tensile stress in the harder component may lead to unstable flow and failure of this component during forming. The observed failures were similar in both plane-strain indentation and rolling tests. Although the initiation of instability in symmetric clad sheet metals appears to be independent of the arrangement of the component layers, the process of final localization leading to fracture was observed to depend heavily on the layer arrangement.
The Strategic Use of Decentralized Institutions: Exploring Certification with the Iso 14001 Management Standard

In this article, we respond to calls by previous researchers to clarify the function of decentralized institutions by analyzing the strategic motives of individual actors. We investigated an important type of decentralized institution, certified management standards, and theorized that firms use these institutions to reduce problems that might arise with exchange partners that lack information or fear opportunism. We tested this theory using the pattern of certification with the ISO 14001 management standard.
"Scar sign" on computed tomography and sonography in fibrolamellar hepatocellular carcinoma.

Demonstration by computed tomography of a central linear or stellate low-attenuation region within a focal liver mass has been reported to be suggestive of focal nodular hyperplasia in appropriate clinical settings. We present a case of a focal liver mass with typical central scarring in which the ultimate diagnosis was fibrolamellar hepatocellular carcinoma.
Somali Nationalism: Its Origins and Future

The Somalis, who almost exclusively inhabit the Horn of Africa, form one of the most uniformly homogeneous populations of the continent. They speak one language, adhere to a single faith, and share a common cultural heritage which is an integral part of their nomadic way of life. The very name So maal, when spoken in the imperative, means ‘Go and milk a beast for yourself’, welcome words of hospitality in a wandering stranger's ears. The Somali's self-conception is inseparable from his flocks and his historical grazing lands. Yet, the Somalis have watched helplessly for the past generation or two as their pasturelands were dismembered by colonising European powers and neighbouring potentates.
Incorporating Spirituality and the Strengths Perspective into Social Work Practice with Addicted Individuals

Abstract In the last two decades, the social work profession began to confront the professional avoidance of alcoholics and other drug addicts, and discussions of spirituality. While acknowledging the importance of 12-Step Programs of Alcoholics/Narcotics Anonymous, we also acknowledge that spirituality is a major aspect of addiction and recovery from an addiction. The authors present the Strengths Perspective and apply key concepts to Steps 1-3 of the 12-Steps to increase our understanding of addiction and recovery from alcoholism and other drug addiction. The article concludes that social workers must continue to increase their understanding of the recovery and spiritual issues of alcoholics and other drug addicts.
Probing the metal ion selectivity in methionine aminopeptidase via changes in the luminescence properties of the enzyme bound europium ion.

Abstract We report herein, for the first time, that Europium ion (Eu3+) binds to the “apo” form of Escherichia coli methionine aminopeptidase (EcMetAP), and such binding results in the activation of the enzyme as well as enhancement in the luminescence intensity of the metal ion. Due to competitive displacement of the enzyme-bound Eu3+ by different metal ions, we could determine the binding affinities of both “activating” and “non-activating” metal ions for the enzyme via fluorescence spectroscopy. The experimental data revealed that among all metal ions, Fe2+ exhibited the highest binding affinity for the enzyme, supporting the notion that it serves as the physiological metal ion for the enzyme. However, the enzyme–metal binding data did not adhere to the Irving–William series. On accounting for the binding affinity vis a vis the catalytic efficiency of the enzyme for different metal ions, it appears evident that that the “coordination states” and the relative softness” of metal ions are the major determinants in facilitating the EcMetAP catalyzed reaction.
Overexpression of the Thiostrepton‐resistance Gene from Streptomyces azureus in Escherichia coli and Characterization of Recognition sites of the 23S rRNA A1067 2′‐methyltransferase in the Guanosine Triphosphatase Center of 23S Ribosomal RNA

The thiostrepton-resistance gene encoding the 23S rRNA A1067 methyltransferase from Streptomyces azureus has been overexpressed in Escherichia coli using a T7-RNA-polymerase-dependent expression vector. The protein was efficiently expressed at levels up to 20% of total soluble protein and purified to near homogeneity. Kinetic parameters for S-adenosyl-l-methionine (Km= 0.1 mM) and an RNA fragment containing nucleotides 1029–1122 of the 23s ribosomal RNA from E. coli (Km= 0.001 mM) were determined. S-Adenosyl-l-homocysteine showed competitive product inhibition (Ki= 0.013 mM). Binding of either thiostrepton or protein L11 inhibited methylation. RNA sequence variants of the RNA fragment with mutations in nucleotides 1051–1108 were tested as substrates for the methylase. The experimental data indicate that methylation is dependent on the secondary structure of the hairpin including nucleotide A1067 and the exact sequence U(1066)-A(1067)-G(1068)-A(1069)-A(1070) of the single strand.
“Nonparametric Local Smoothing” is not image registration

Background Image registration is one of the most important and universally useful computational tasks in biomedical image analysis. A recent article by Xing & Qiu (IEEE Transactions on Pattern Analysis and Machine Intelligence, 33(10):2081–2092, 2011) is based on an inappropriately narrow conceptualization of the image registration problem as the task of making two images look alike, which disregards whether the established spatial correspondence is plausible. The authors propose a new algorithm, Nonparametric Local Smoothing (NLS) for image registration, but use image similarities alone as a measure of registration performance, although these measures do not relate reliably to the realism of the correspondence map.
THE ISOLATION AND BIOLOGICAL ACTIVITIES OF RABBIT GAMMA M- AND GAMMA G-ANTI-SALMONELLA TYPHIMURIUM ANTIBODIES.

Rabbit γM- and γG-anti-S. typhimurium antibodies were isolated by combined immune specific and physical methods and some of their properties in immunological systems were measured. γM-Antibody was detectable at lower concentrations and revealed a higher specific activity than the γG-globulins. Indirect studies indicated that the γG-globulin was the more "avid" immunoglobulin. Treatment of the γM-globulin with the reducing agent 2-ME decreased but did not destroy the immune activity of the subunits. The results confirm the necessity of analysis of purified immunoglobulin antibodies to evaluate the significance of their biological properties secondary to their interaction with antigens.
Creating and using domain-specific language features

The value that domain-specific languages provide to their users is the domain-specific language features they contain. These features provide notations from the domain of interest, as well as domain-specific analysis and optimizations. But domain-specific languages are sometimes a poor means of delivering these valuable features to their users. A challenge arises when a problem crosses multiple domains and whose programming or modeling solution could benefit from language features from all domains of interest. Using multiple domain-specific languages can become cumbersome, perhaps outweighing their benefits in the first place.An alternative approach, advocated by this position paper, is to provide domain-specific language features to programmers and modelers as composable language extensions that they can import into their general-purpose programming or modeling language. In our view, there are three requirements for a language extension framework to be widely usable. First, language extensions should be developed independently, by domain-experts, as libraries or domain-specific languages are now. Second, extensions should be automatically composable so that programmers and modelers can pick the language extensions they want, and direct tools to compose them, without the need for writing "glue-code." Third, this composition process should not fail to yield a working compiler (or other tools) for the custom extended language. Thus, the programmer has some assurance that the extensions that they pick will work together.We briefly describe how this vision of extensible language frameworks is supported by the Silver and Copper metaprogramming tools.
Role of endogenous sulfur-containing nucleophiles in an in vitro model of cis-diamminedichloroplatinum(II)-induced nephrotoxicity

Quiescent LLC-PK1 cells have been shown to be a good model of cis-diamminedichloroplatinum(II) (DDP)-induced nephrotoxicity. In these nonproliferating porcine kidney epithelial cells, DDP inhibition of protein synthesis rate is the major correlate of cytotoxicity. We report here the use of this cell line to investigate the role of endogenous sulfur-containing nucleophiles in DDP-induced nephrotoxicity. Reaction of DDP with glutathione (GSH), cysteine, or methionine for up to 24 hr led to concentration- and time-dependent loss of its toxic effects, whereas dissolution of DDP alone did not alter its reduction of viability or protein synthesis rate in LLC-PK1 cells. Treatment of these cells with differing cytotoxic concentration of DDP produced an identical transient increase in intracellular GSH, whereas compounds known to bind GSH, trans-diamminedichloroplatinum(II) (t-DDP) and diethyl maleate (DEM), rapidly depleted LLC-PK1 intracellular GSH levels. Buthionine sulfoximine (BSO) treatment decreased intracellular GSH to 10% of control without altering cell viability or protein synthesis rate. However, BSO-pretreated LLC-PK1 cells exhibited enhanced DDP-induced toxicity. CdCl2 treatment produced a 30-fold induction of metallothionein-like, cadmium-binding proteins and a 10-fold increase in metallothionein isoform I (MT-I) mRNA, but this induction had no effect on DDP-induced reduction of viability or protein synthesis rate. Protracted DDP exposure did not induce MT-I mRNA levels in LLC-PK1 cells.