cssi/SciSciGPT-SciSciNet huggingface dataset:
Crystallization and preliminary X-ray studies of human erythrocyte acylpeptide hydrolase.

Crystals of acylpeptide hydrolase suitable for structure determination have been obtained. This enzyme removes the N-terminal formyl or acetyl group together with the first amino acid residue from N-terminal blocked peptides including bioactive peptides. One set of crystals, which diffract to 2·2 A, are in space group P2 with cell dimensions a = 118·6 A, b = 82·3 A, c = 182·1 A, β = 91·6°. The search for suitable heavy-atom derivatives is underway.
Immune Responses to Exercising in a Cold Environment

Cold temperature and exercise independently impose stress on the human body that can lead to circulatory and metabolic changes, and depress the immune system. Multiple stressors applied together may amplify this immunodepression, causing greater immune impairment and heightened infection risk than with either stressor alone. As such, winter athletes and other persons who work or physically exert themselves in cold temperatures may have greater levels of stress-induced immune impairment than would be expected under mild temperatures. This review examines the literature regarding changes to physiological and immunological parameters arising from exposure to cold temperatures and to exercise. Even brief exposure to cold leads to increased levels of norepinephrine and cortisol, lymphocytosis, decreased lymphoproliferative responses, decreased levels of TH1 cytokines and salivary IgA, and increased lactate levels during exercise. Whether these changes lead to increased susceptibility to infection, as suggested by some epidemiological reports, remains to be determined. Although there is some evidence that exercising in temperatures near 5°C leads to greater immune impairment compared to exercising in milder temperatures, there is a need to explore the effects of exercise on immunity in the subfreezing conditions typically encountered by winter athletes. This is required to fully determine the extent to which performing vigorous exercise in subfreezing temperatures amplifies exercise-induced immune impairment and infection risk.
IRE1 couples endoplasmic reticulum load to secretory capacity by processing the XBP-1 mRNA

The unfolded protein response (UPR), caused by stress, matches the folding capacity of endoplasmic reticulum (ER) to the load of client proteins in the organelle. In yeast, processing of HAC1 mRNA by activated Ire1 leads to synthesis of the transcription factor Hac1 and activation of the UPR. The responses to activated IRE1 in metazoans are less well understood. Here we demonstrate that mutations in either ire-1 or the transcription-factor-encoding xbp-1 gene abolished the UPR in Caenorhabditis elegans. Mammalian XBP-1 is essential for immunoglobulin secretion and development of plasma cells, and high levels of XBP-1 messenger RNA are found in specialized secretory cells. Activation of the UPR causes IRE1-dependent splicing of a small intron from the XBP-1 mRNA both in C. elegans and mice. The protein encoded by the processed murine XBP-1 mRNA accumulated during the UPR, whereas the protein encoded by unprocessed mRNA did not. Purified mouse IRE1 accurately cleaved XBP-1 mRNA in vitro, indicating that XBP-1 mRNA is a direct target of IRE1 endonucleolytic activity. Our findings suggest that physiological ER load regulates a developmental decision in higher eukaryotes.
An analysis of modulated molecular beam mass spectrometry applied to nonlinear systems

Abstract We have extended a formalism, developed previously to describe linear systems [H.-C. Chang and W.H. Weinberg, J. Chem. Phys. 66 (1977) 4176; Surface Sci. 65 (1977) 153], to the case of nonlinear reaction models in an analysis of modulated molecular beam mass spectrometry. The formalism is derived explicitly for the case of nonlinear surface reactions, adsorption with a coverage dependent sticking probability, and coupled bulk diffusion and nonlinear reaction. Specific examples illustrating how the formalism may be applied include the catalytic decomposition of formic acid on platinum and the reaction of fluorine with tantalum.
Role of phosphorylation in conformational adaptability of bovine myelin basic protein

Controlled thrombic diges- tion of a preparation of components 2 + 3 iso- lated from the 18.5 kDa bovine myelin basic protein (MBP) yielded a polypeptide that was monophosphorylated on threonine 97 (compo- nent 3pT97). This is the first posttranslationally phosphorylated MBP isolated in pure form. We studied the effect of this single phosphate on the conformational adaptability of 18.5 kDa bo- vine MBP by comparing the circular dichroism (CD) spectrum of component 3pT97 with the spectra of highly purified nonphosphorylated components 1 and 2. The CD spectra of non- phosphorylated component 1 and component 2 (monodeamidated form(s) of component 11 were indistinguishable, while component 3pt97 ex- hibited a different spectrum. The singly phos- phorylated MBP component exhibited 13% more ordered conformations than that adopted by nonphosphorylated MBP in dilute aqueous solutions. This was estimated from the CD spec- tra, and apparently involved about 17 addi- tional amino acid residues in p-structure(s).
Fracture at the Margins of Amalgam as Predicted by Creep, Zinc Content, and Gamma-2 Content

Regression equations and correlations were used to evaluate the in vitro and in vivo relationship of marginal breakdown of amalgam alloys. Interpretation of the results indicates that gamma-2 and non-gamma-2 alloys comprise two distinct groups. Equations based upon in vitro data predicting marginal breakdown for gamma-2 alloys should not be used for non-gamma-2 alloys.
New developments and directions in the area of elastomers and rubberlike elasticity

There are number of important developments in the area of elastomeric polymers, including (i) network chains of controlled stiffness, (ii) model elastomers (including dangling-chain networks), (iii) fluorosiloxane elastomers, (iv) new thermoplastic elastomers, (v) other new elastomers, (v) bimodal network chain-length distributions, (vi) cross linking in solution or in a state of deformation, and (vii) gel collapse. Interesting elastomeric composites include those with (i) in-situ generated ceramic-like particles, (ii) ellipsoidal fillers, (iii) clay-like layered fillers, (iv) polyhedral oligomeric silsesquioxane (POSS) particles, (v) porous fillers, (vi) elastomeric domains modifying ceramics, and (vii) controlled interfaces. New characterization techniques are being developed for elastomers, and there have been new developments in elasticity theory and in elastomer processing. Some examples of societal aspects of relevance are (i) synthesis of elastomers in environmentally-friendly solvents, (ii) biosynthesis, (iii), recyclability, (iv) improved adhesion to tire cords, and (v) better barrier properties in anti-terrorism clothing. Educational topics include curriculum development, and mobile laboratories for elastomer experiments and demonstrations.
Helix-Coil, Liquid Crystal, and Spin Glass Transitions of a Collapsed Heteropolymer

Using simple statistical mechanical models, we investigate secondary structure formation in the molten globule state of a helix-forming heteropolymer. The theory based on the helix-coil model of Bragg and Zimm correctly treats the one-dimensional aspect of the helix-coil transition but has been modified to include the randomness effects of the tertiary interactions in a heteropolymer. Rough approximations to the effects of confinement, excluded volume, and packing order of the helices are used to give the resulting generalization of the random energy model. In this model the packing effects give rise to a liquid crystalline order in the molten globule state. For reasonable values of parameters at the spin glass transition, we estimate that the heteropolymer is about 80% helical with helix lengths of order 20. Analysis of this simple model allows an estimate of the effective Levinthal entropy and determines that about 10" configurations would have to be searched at the glass transition for a 100-mer.
Flow injection for continuous sample introduction in solid-substrate room-temperature phosphorescence

Abstract The feasibility of using flow injection as a continuous sample introduction method for solid-surface room-temperature phosphorescence (SSRTP) is studied. A two-nebulizer system is used to spray the heavy-atom and analyte solutions separately onto the moving filter-paper strip. The analytical figures of merit obtained for three well known phosphorescent compounds show that flow injection can be successfully employed in SSRTP methods.
Awakening to the Behavioral Analysis of Sleep in Drosophila

Perhaps the most observable of the many circadian oscillations that have been described in both vertebrate and invertebrate animals is the daily alterations in periods of rest and activity. Recent studies in the fruit fly Drosophila melanogaster suggest that these periods of inactivity are not simply rest but share many of the fundamental components that define mammalian sleep. Thus, quiescent episodes are characterized by reduced awareness of the environment and are homeostatically regulated. Although this field is in its infancy, recent studies have focused on the interaction between circadian and homeostatic processes. These results indicate that components of the circadian clock may play a substantial role in mechanisms underlying sleep homeostasis at the molecular level. In this article, the author reviews recent advances obtained using Drosophila as a model system to elucidate fundamental components of sleep regulation.
Groupware: a strategic analysis and implementation

The term groupware is widely used but not clearly defined. Owing to ongoing rapid developments, a consistent definition of the term has proved elusive. However, there is a good reason to view groupware as a technology that addresses the vast areas of collaboration, human‐computer interaction, and human‐human interaction through digital media to bring substantial improvement and transformation to organizations. This paper analyzes the definitions, implementation, and management of groupware. The focus is on the strategic considerations rather than technical solutions. Factors that contribute to the future development of groupware are also discussed.
Epidemiologic Characteristics of Prostate Cancer

Both genetic and exogenous factors are probably important in prostate cancer development, but the specific causes remain poorly understood. An increasing body of evidence now suggests that high animal fat or red meat intake appears to increase risk for this cancer. Some studies indicate that high intake of retinol may be deleterious, but β-carotene may lower risk, although these data are inconsistent. Carotenoids other than β-carotene are only now being examined in relation to prostate cancer risk. Ongoing epidemiologic studies may help clarify the relation between diet and prostate cancer. Most studies indicate that men who have had a vasectomy have an increased risk for prostate cancer to develop, although whether this association is causal is unknown. Familial factors are important, particularly at younger ages. Overall, about 9% of cases may be attributed directly to a family history of prostate cancer, although this may be as high as 43% among men younger than 55 years. No occupational factor has been confirmed as a risk factor. Some evidence suggests that occupational exposure to cadmium and some aspect of farming may increase risk moderately, but these would account for a small proportion of the total cases. Dietary factors appear to hold the most promise for primary prevention, but the precise factors and mechanisms need to be better understood. Cancer 1995 ;75 :1766-77.
Genetic disruption of the scaffolding protein, Kinase Suppressor of Ras 1 (KSR1), differentially regulates GM-CSF-stimulated hyperproliferation in hematopoietic progenitors expressing activating PTPN11 mutants D61Y and E76K.

Activating PTPN11 mutants promote hematopoietic progenitor hyperactivation of Erk and hypersensitivity to GM-CSF. We hypothesized that Kinase Suppressor of Ras 1 (KSR1) contributes to activating PTPN11-induced GM-CSF hypersensitivity. Bone marrow progenitors from WT and KSR1−/− mice expressing WT Shp2, Shp2E76K, or Shp2D61Y were evaluated functionally and biochemically. KSR1 activation and interaction with phospho-Erk was enhanced in Shp2D61Y- and ShpE76K-expressing cells. Genetic disruption of KSR1 partially normalized Shp2E76K-induced GM-CSF hypersensitivity, but failed to correct Shp2D61Y-induced GM-CSF hypersensitivity. Collectively, these studies suggest that cells expressing Shp2E76K have a greater dependence on KSR1 for GM-CSF hypersensitivity than cells expressing Shp2D61Y.
Enhancing visuospatial performance through video game training to increase learning in visuospatial science domains

Although previous research has demonstrated that performance on visuospatial assessments can be enhanced through relevant experience, an unaddressed question is whether such experience also produces a similar increase in target domains (such as science learning) where visuospatial abilities are directly relevant for performance. In the present study, participants completed either spatial or nonspatial training via interaction with video games and were then asked to read and learn about the geologic topic of plate tectonics. Results replicate the benefit of playing appropriate video games in enhancing visuospatial performance and demonstrate that this facilitation also manifests itself in learning science topics that are visuospatial in nature. This novel result suggests that visuospatial training not only can impact performance on measures of spatial functioning, but also can affect performance in content areas in which these abilities are utilized.
Pathophysiology of Dental Disease in the Rabbit, Guinea Pig, and Chinchilla

Abstract This article presents a review of differences in physioanatomy of the masticatory apparatus and pathophysiology of dental disease in rabbits, guinea pigs, and chinchillas. The entire dentition of these commonly kept pets is aradicular hypsodont, with teeth that continue to grow throughout life. This peculiarity of nature is present in animals with marked chewing behavior and allows replacement of tooth substance that is lost because of constant abrasive wear. Evidence is emerging that inappropriate physical form and composition of the diet may be responsible for tooth elongation and associated conditions in captive lagomorphs and rodents.
Evaluating Policy Interventions with General Equilibrium Externalities

Abstract We report on the results of analytical and numerical models that describe the effects of non-separable externalities (or public goods) on public policies with important general equilibrium consequences. In the numerical exercise, we calibrate a general equilibrium model with non-separable air quality benefits in order to measure the excess burden and total net benefits of transportation and energy taxes in the 1995 U.S. economy. The change in the physical level and the economic value in air quality associated with a given policy is a function of the substitution patterns between air quality and market goods that we assume. The size of the deadweight loss due to pre-existing distortions such as a tax on labor income is substantially affected by these substitution patterns.
Cyclooxygenase-2 inhibitor blocks expression of mediators of renal injury in a model of diabetes and hypertension1

Cyclooxygenase-2 inhibitor blocks expression of mediators of renal injury in a model of diabetes and hypertension. Background We previously reported that renal cortical cyclooxygenase (COX-2) expression increased following subtotal nephrectomy, and chronic treatment with a selective COX-2 inhibitor, SC58236, reduced proteinuria and retarded the development of glomerulosclerosis. The present studies were designed to examine the effects of COX-2 inhibition in a model of diabetic nephropathy. Methods Rats were divided into three groups: control, diabetic (streptozotocin-induced diabetic animals with superimposed DOCA/salt hypertension; right nephrectomy and DOCA treatment), and treated (administration of the selective COX-2 inhibitor, SC58236, to a subset of diabetic/DOCA/salt rats). Insulin was administered to maintain blood glucose in the 200 to 300 mg/dL range. Results Systolic blood pressure in the two diabetic groups was elevated within one week and remained elevated until sacrifice at six weeks (control, 108 ± 2 mm Hg; diabetic, 158 ± 4 mm Hg; treated, 156 ± 7 mm Hg). When measured at six weeks, immunoreactive COX-2 expression in the renal cortex of the diabetic rats was 2.5 ± 0.3-fold of control animals ( N = 7). Immunohistochemical localization indicated increased expression in macula densa and surrounding cortical thick ascending limb of Henle (cTALH). The COX-2 inhibitor decreased COX-2 expression in diabetic rats to 1.3 ± 0.1-fold control. In addition, SC58236 decreased expression of PAI-1 (diabetic vs. treated, 3.2 ± 0.5 vs. 1.7 ± 0.2-fold control, N = 7, P N = 7, P N = 7, P N = 7, P N = 7, P P Conclusions These results suggest that in an experimental model of diabetes and hypertension, inhibition of COX-2 expression decreases potential mediators of glomerular and tubulointerstitial injury and also decreases biochemical, functional and structural markers of renal injury.
Bats of Vieques National Wildlife Refuge, Puerto Rico, Greater Antilles

Herein, we present captures of bats from Vieques, a small subtropical island located southeast of Puerto Rico. We captured 82 individuals representing 4 species, including 59 Noctilio leporinus , 9 Artibeus jamaicensis , 9 Molossus molossus , and 5 Stenoderma rufum . All S. rufum and M. molossus were captured in subtropical moist forests, whereas both N. leporinus and A. jamaicensis were captured in both subtropical moist and dry forests. Sternoderma rufum is an endemic species of concern in the region. Vieques represents only the 5th island where this relatively rare species has been captured in the past 30 years. Conservation of subtropical moist forests on Vieques likely is important for the conservation and management of S. rufum and additional information about the natural history of all bats is warranted on Vieques.
Irreversible optic neuropathy in wernicke encephalopathy and leber hereditary optic neuropathy.

Abstract:A 52-year-old woman with alcohol abuse presented with recent worsening of vision, imbalance, and confusion. Examination revealed counting fingers acuity in both eyes with central scotomas, color vision loss, horizontal nystagmus, and gait ataxia. Thiamine was initiated as treatment for a pr
Massive degloving injury of the trunk

A case of massive degloving injury of the perineum, thigh, and buttocks is presented. Hemostasis was achieved with a pneumatic anti-shock garment (PASG), followed by direct suturing of bleeding areas. A colostomy was performed. Initial conservative debridement was followed in ten days by multiple skin grafts. The patient was treated with sodium bicarbonate and mannitol to preclude myoglobinuric renal failure. Intravenous hyperalimentation was also utilized.
Expression of a testis β-tubulin gene in Heliothis virescens during spermatogenesis

Abstract A cDNA library has been constructed from Heliothis virescens testes poly(A) + RNA, and a Heliothis cDNA clone isolated using a testis-specific β-tubulin sequence from Drosophila . The Heliothis cDNA was identified as corresponding to a β-tubulin sequence by hybrid-selected translation. A transcript from the Heliothis β-tubulin gene was abundant in testes, but undetectable in 0–48 h embryos, larval fat body, adult ovaries or ovarian derived cultured cells. The testis β-tubulin gene was expressed throughout all stages of spermatogenesis examined. The data suggest that the encoded testis-specific polypeptide may be involved in the assembly of multiple rather than single microtubular structures formed during sperm cell differentiation. Although the β-tubulin transcript was present throughout all stages of spermatogenesis, the steady-state level of the transcript varied during different stages of spermatogenesis, indicating some degree of temporal regulation of either rate of transcription or RNA stability.
High frequency Faraday rotation in FR-5 glass.

The frequency dependence of the Faraday effect is studied in FR-5, a Tb-doped borosilicate glass. Data were obtained between 5 and 30 K. (AIP)
The microcomputer performance of uniform variate random number generators expressed in FORTRAN

Abstract The microcomputer performance of random number generators is an important component of uncertainty analysis in environmental modeling. The results of a performance study of 110 uniform variate pseudo-random number generators expressed in FORTRAN are presented. The algorithms tested include multiplicative, mixed, additive and quadratic congruential generators plus example combined and generalized feedback shift register generators. Results are presented for generator speed, period, and 17 statistical measures of number randomness quality. These results indicate that, based on both speed and number quality, the multiplicative linear congruential generator can yield superior performance. Specific moduli and multipliers are recommended for this generator. For relatively low period generators, explicit use of the integer modulus function provides superior performance. When high period generators are implemented, they should be based on the Schrage (1979) or Bongiovanni (1987) computational procedure for accomplishing the modulus operation with arithmetic that avoids explicit use of the modulus function.
Modification of Growth and Development of Muscles of Poultry

Growth curves of selected and unselected lines of broilers and Japanese quail show that chicks respond to selection for 8-week or 4-week body mass, respectively, by increasing the exponential growth rate during the first 2 weeks after hatching. Comparative studies indicate that growth rate varies among species of birds according to adult body mass, developmental maturity of the chick at hatching, and the postnatal growth increments of the skeletal muscles of the legs. Differentiation of tissues leading to mature function apparently precludes embryonic function and decreases proliferation and growth. Precocial species, such as the domestic fowl, grow only one-quarter as fast, on average, as altricial species of the same size, whose chicks are less mature at hatching and depend more on parental care for food, warmth, and protection. Among precocial species, those whose legs have the smallest postnatal growth increments grow most rapidly overall. The domestic fowl is among the slowest growing of precocial species. Although diet quality may limit growth rate, this should not be a factor in selection programs, because high quality diets can be provided. Rate of food assimilation apparently also is limiting, but it can be increased experimentally by force feeding and presumably is sufficiently selectable so as not to limit breeding programs designed to increase growth rate. The response of broilers and quail to selection of body mass apparently affects the rate of proliferation of skeletal muscles during the early posthatching period. Muscle quality is not affected. There is inconclusive evidence of a shift in muscle cell nuclei from differentiated to proliferative pools in selected lines. Furthermore, selected broilers apparently are less capable than unselected chicks of generating body heat, which requires functional skeletal muscle during the first week posthatching. Growth performance of broilers might be increased beyond present levels by selecting directly for reduced or delayed maturity (e.g., thermogenesis, flight) of chicks during the first 2 weeks and by selecting smaller legs in adult birds. Any attempt to formulate a selection program on these ideas would require additional basic research and might be thwarted by economic considerations or by offsetting selection caused by phenotypic responses that strain certain functional relationships in the growing chick.
Alpha Interferon, Leucovorin, and 5-Fluorouracil (ALF) in Advanced Cancer: Results of a Dose-Finding Study and Evidence of Activity in Non-Small Cell Lung Cancer

In a phase I trial, 17 patients were treated with 5-fluorouracil (5-FU) 500 mg/m2 and leucovorin (LV) 500 mg/m2 intravenously weekly for 6 weeks followed by 2 weeks’ rest and interferon alfa-2b 1, 3, 5, 8, or 10 million units (MU) subcutaneously tiw with no rest period. The most common toxicities were fatigue (12), diarrhea (10), nausealvomiting (7), and fever (7). The maximum tolerated interferon dose was 8 MU tiw. Fatigue and increased incidence of other toxicities rather than a single dose-limiting toxicity occurred at the next highest interferon level. ECOG grade III/IV toxicity occurred in 5 patients and included transient supraventricular tachycardia and brief seizure episode (1), dyspnea (1), decreased performance status (1), anemia requiring transfusion (1), and deep vein thrombosis (1). No toxic deaths occurred. Two patients with non-small cell lung cancer (NSCLC) had partial responses lasting 5 and 4 months. Two other patients with NSCLC had either minor response or stable disease, and 1 patient...
Differential contributions of dorsal hippocampal subregions to memory acquisition and retrieval in contextual fear-conditioning.

The hippocampus is an essential neural structure in developing contextual memory in a situation in which rapid development of associative learning should occur. We tested a subregion-specific contribution in the hippocampus to memory acquisition and retrieval, using the contextual fear-conditioning paradigm. The current results suggest that all three subregions (i.e., CA3, CA1, and dentate gyrus) of the hippocampus contribute to rapid acquisition of contextual memory in the initial phase of acquisition. The involvement of CA3 seems to be important at the earliest stage of acquisition, presumably for developing instant representation of a context. The role of CA3, however, was minimal in retrieving contextual memory after a long time period (i.e., 24 h), whereas the other subregions (i.e., CA1 and dentate gyrus) were critically involved. The results indicate time-dependent differential contributions of the hippocampal subregions to memory acquisition and retrieval in contextual fear-conditioning. © 2004 Wiley-Liss, Inc.
Microbiologic Determination of Drug Partitioning I: Gelatin—Acacia Complex Coacervate System

An experimental method was developed for the determination of the extent of the partitioning of phenylmercuric nitrate in coacervate systems, as measured by the effect of the antimicrobial drug on the growth of Escherichia coli. Bacterial growth is utilized to investigate changes in the coacervate partition coefficient as a function of drug concentration. The method is sensitive for microgram quantities of this antimicrobial agent and is useful in drug partitioning at levels found in physiologic systems.
Micropower generation using combustion: Issues and approaches

The push toward the miniaturization of electro-mechanical devices and the resulting need for micro-power generation (milli-watts to watts) with low-weight, long-life devices has led to the recent development of the field of micro-scale combustion. The concept behind this new field is that since batteries have low specific energy, and liquid hydrocarbon fuels have a very high specific energy, a miniaturized power generating device, even with a relatively inefficient conversion of hydrocarbon fuels to power would result in increased lifetime and/or reduced weight of an electronic or mechanical system that currently requires batteries for power. In addition to the interest in miniaturization, the field is also driven by the potential fabrication of the devices using Micro Electro Mechanical Systems (MEMS) or rapid prototyping techniques, with their favorable characteristics for mass production and low cost. The micro-power generation field is very young, and still is in most cases in the feasibility stage. However, considering that it is a new frontier of technological development, and that only a few projects have been funded, it can be said that significant progress has been made to date. Currently there is consensus, at least among those working in the field, that combustion in the micro-scale is possible with proper thermal and chemical management. Several meso-scale and micro-scale combustors have been developed that appear to operate with good combustion efficiency. Some of these combustors have been applied to energize thermoelectric systems to produce electrical power, although with low overall efficiency. Several turbines/engines have also been, or are being, developed, some of them currently producing positive power, also with low efficiency to date. Micro-rockets using solid or liquid fuels have been built and shown to produce thrust. Hydrogen-based micro size fuel cells have been successfully developed, and there is a need to develop reliable reformers (or direct-conversion fuel cells) for liquid hydrocarbons so that the fuel cells become competitive with batteries. In this work, some of the technological issues related to meso and micro-scale combustion and the operation of thermochemical devices for power generation will be discussed. Some of the systems currently being developed will be presented and described.
Photosynthetic and growth responses of cattail (Typha domingensis) and sawgrass (Cladium jamaicense) to soil redox conditions

Abstract Under controlled laboratory conditions, cattail ( Typha domingensis Pers.) and sawgrass ( Cladium jamaicense Crantz) were subjected to a range of soil redox potential (Eh) including +500, +250, 0 and −200 mV and plant photosynthetic activity and growth responses were measured. In both species, light saturation was not achieved at the highest photon irradiance of 1100 μmol m −2 s −1 . Sawgrass showed greater photosynthetic capacity per unit area of leaf at higher irradiances than cattail. However, light compensation points were estimated at 25 and 60 μmol m −2 s −1 for cattail and sawgrass, respectively. In both species, stomatal conductance was reduced significantly in response to the lowest Eh condition (−200 mV). Net photosynthesis decreased significantly in both species in response to the reduced Eh conditions, but there were differences. The reductions were proportionally greater in sawgrass than in cattail. Thus, at −200 mV Eh, net photosynthesis was reduced by 71% for cattail; while in sawgrass there was no net photosynthesis, only respiration. Cattail showed significantly greater net photosynthetic rates as compared with sawgrass at the lowest Eh treatment (−200 mV). Although total biomass was reduced in both species in response to low Eh conditions, it nevertheless was significantly greater in cattail than sawgrass under 0 and −200 mV soil Eh treatments. However, the biomass allocation pattern did not differ between the two species across treatments. Results of the present study support the hypothesis that in both species differences in pattern of site occupancy and competition under low soil oxygen conditions may be partially explained by differences in their photosynthetic characteristics and photosynthetic acclimation to oxygen-deficient environments.
Transcriptional dysregulation in a transgenic model of Parkinson disease

Alpha-synuclein has been implicated in Parkinson disease, yet the mechanism by which alpha-synuclein causes cell injury is not understood. Using a transgenic mouse model, we evaluated the effect of alpha-synuclein overexpression on gene expression in the substantia nigra. Nigral mRNA from wild type and alpha-synuclein transgenic mice was analyzed using Affymetrix gene arrays. At 3 months, before pathological changes are apparent, we observed modest alterations in gene expression. However, nearly 200 genes were altered in expression at 9 months, when degenerative changes are more apparent. Functional genomic analysis revealed that the genes altered at 9 months were predominantly involved in gene transcription. As in human Parkinson disease, gene expression changes in the transgenic model were also modulated by gender. These data demonstrate that alterations of gene expression are widespread in this animal model, and suggest that transcriptional dysregulation may be a disease mechanism that can be targeted therapeutically.
Reference Service Policies

It is the implicit policy of most reference departments to serve the public as fully as time and money permit. Yet, since libraries vary in the quality and number of reference services they provide, patrons and new employees welcome formal statements of departmental priorities and procedures. Janet Easley presents five reasons for developing a reference service policy.
N-Glycan Moieties in Neonatal Fc Receptor Determine Steady-state Membrane Distribution and Directional Transport of IgG

The neonatal Fc receptor (FcRn) is a major histocompatibility complex class I-related molecule known to protect IgG and albumin from catabolism and transport IgG across polarized epithelial cells in a bidirectional manner. Previous studies have shown species-specific differences in ligand binding, IgG transport direction, and steady-state membrane distribution when expressed in polarized epithelial cells. We hypothesized that these differences may be due to the additional N-glycans expressed on the rat FcRn, because N-glycans have been proposed to function as apical targeting signals, and that two of the N-glycan moieties have been shown to contribute to the IgG binding of rat FcRn. A panel of mutant human FcRn variants was generated to resemble the N-glycan expression of rat FcRn in various combinations and subsequently transfected into Madin-Darby canine kidney II cells together with human β2-microglobulin. Mutant human FcRn clones that contained additional N-glycan side-chain modifications, including that which was fully rodentized, still exhibited specificity for human IgG and failed to bind to mouse IgG. At steady state, the mutant human FcRn with additional N-glycans redistributed to the apical cell surface similar to that of rat FcRn. Furthermore, the rodentized human FcRn exhibited a reversal of IgG transport with predominant transcytosis from an apical-to-basolateral direction, which resembled that of the rat FcRn isoform. These studies show that the N-glycans in FcRn contribute significantly to the steady-state membrane distribution and direction of IgG transport in polarized epithelia.
Viability of Sarcocystis neurona sporocysts after long-term storage.

Abstract The effect of long-term storage on the viability and infectivity of Sarcocystis neurona sporocysts was investigated. S. neurona sporocysts were harvested from the small intestine of Virginia opossums from 1996 to 2002 and stored at 4 °C. Viability of sporocysts was assessed by propidium iodide (PI) exclusion assay, in vitro excystation and development in tissue cultures, and bioassay in gamma-interferon gene knockout (γ-IFN-KO) mice. The rate of excystation was apparently unaffected by long-term storage; sporocysts retained their ability to excyst after 7 years of storage at 4 °C. However, the ability of sporocysts to exclude PI stain, to invade and proliferate in cells in vitro, and to cause disease and lesions in γ-IFN-KO mice appeared to decline as sporocysts age. The results demonstrated that sporocysts of S. neurona were able to survive and maintain moderate to high viability for up to 7 years when stored in phosphate buffered saline and Hank’s balanced salt solution containing antibiotic–antimycotic mixture at 4 °C.
Electromechanical properties and molecular conformation in P(VDF-TrFE)-based terpolymer

The recent discovery of high electromechanical performance in high-energy electron irradiated P(VDF-TrFE) copolymers opens a new avenue for developing high performance electroactive polymers. From basic materials consideration, it is expected that one can achieve high electromechanical performance by means of nonirradiation approach, such as introducing ter-monomer to form PVDF based terpolymer. The basic requirement for the ter-monomer is discussed in order to achieve a high electromechanical performance in P(VDF-TrFE) based terpolymer. Based on the conclusion, P(VDF-TrFE-CFE) terpolymer has been synthesized and the experimental results indicate that the terpolymer exhibits better electromechanical performance compared with irradiated copolymers. For example, both the electric induced strain and Young's modulus in P(VDF-TrFE-CFE) terpolymer could be higher than that in irradiated copolymers. X-ray diffraction, DSC and FTIR were employed to determine the structure and molecule conformation. Furthermore, a serious theoretical simulation was carried out for P(VDF-TrFE) based terpolymers with different ter-monomers. The results show that indeed the terpolymer with CFE favors gauche conformation, consistent with the experimental results.© (2002) COPYRIGHT SPIE--The International Society for Optical Engineering. Downloading of the abstract is permitted for personal use only.
Thick smectic shells

Abstract The known ground state of ultrathin smectic films confined to the surface of a sphere is described by four +1/2 defects assembled on a great circle and a director which follows geodesic lines. Using a simple perturbative approach we show that for thick smectic films on a sphere with planar anchoring this solution breaks down, distorting the smectic layers. The instability happens when the bend elastic constant exceeds the anchoring strength times the radius of the inner sphere. Above this threshold, the formation of a periodic chevron-like structure, observed experimentally as well, relieves geometric frustration. We quantify the effect of thickness and curvature of smectic shells and provide insight into the wavelength of the observed texture.
Parkinsonism due to a basal ganglia lacunar state: Clinicopathologic correlation

We report a patient with a clinical syndrome indistinguishable from Parkinson's disease in which postmortem examination revealed extensive lacunar infarction of the basal ganglia without evidence of coexistent Parkinson's disease. This case provides pathologic confirmation of the concept of vascular parkinsonism.
Thermal Transients in Electronic Packages

The use of a transient analysis to accurately characterize the operating temperature of electronic modules should result in lower temperature estimates. This will reflect increases in both the reliability estimates and the performance specifications. An accurate cooling analysis would also enhance the projected product life or reduce the system cooling requirements. Simplified expressions have been obtained for the calculation of chip and module thermal transients which, when superimposed, characterize the total package time/temperature response. Empirical data demonstrate the validity of the assumptions used to obtain these expressions. The thermal time constants are also presented in graphical form using parameters easily obtainable by the design engineer (e.g., cooling air velocity, steadystate temperature differences, and module location) so that order of magnitude assessments can be made.
Development of rheumatoid factor research through 50 years.

The discovery of Waaler in 1937 initiated fruitful research on RFs. It was not until the early 1960s that investigators in the field agreed that RFs are antibodies to Fc fragment of IgG. Separate factors combining with human and rabbit IgG and a factor combining with both these IgGs were at first demonstrated by mixed agglutination and then by separation through IgG-conjugated columns. Only RF combining with native autologous IgG should be considered an autoantibody. Other RFs are allo- or heteroantibodies. Cross-reacting RFs that combine with IgG of various species or with IgG and antigens of cell nuclei are of considerable interest. This cross-reactivity may be due to a combining site interacting with shared epitopes or otherwise to multispeuticity of the RF molecule in that it has separate or partially overlapping combining sites acting on different epitopes. Experimental studies conducted since the mid-1950s showed that formation of RFs may be elicited by altered autologous IgG. Under natural conditio...
Exponential error bounds for random codes on Gaussian arbitrarily varying channels

The main objective is to develop exponential bounds to the best error probability achievable with random coding on the Gaussian arbitrarily varying channel (GAVC) in the one case where a (strong) capacity exists (i.e., with peak time-averaged power constraints on both the transmitter and interference). The GAVC models a channel corrupted by thermal noise and by an unknown interfering signal of bounded power. The upper and lower bounds to the best error probability achievable on this channel with random coding are presented. The asymptotic exponents of these bounds agree in a range of rates near capacity. The exponents are universally larger than the corresponding exponents for the discrete-time Gaussian channel with the same capacity. It is further shown that the decoder can be taken to be the minimum Euclidean distance rule at all rates less than capacity. >
Effects of exercise training and amino-acid supplementation on body composition and physical performance in untrained women.

Abstract The purpose of this study was to determine the effects of 6 wk of essential amino acid (EAA) supplementation on body composition and exercise performance in untrained women ( n = 21). Subjects were randomly assigned to a placebo (cellulose) or an EAA (average daily dose of 18.3 g of EAAs in pill form) group. Each subject participated in aerobic and heavy-resistance training three times per week. Body composition was assessed via dual x-ray absorptiometry analysis. Muscular endurance was determined via treadmill time to exhaustion, and strength was assessed by the total amount of weight lifted for one set to exhaustion at an estimated 12 repetitions maximum. No changes occurred in either group for body weight, lean body mass, fat mass, or bone mineral content. Treadmill time to exhaustion (TTE) improved significantly ( P
THE ANALYSIS OF LINKAGES IN DEMOGRAPHIC THEORY

Many seemingly different questions that arise in the analysis of population change can be phrased as the same technical question: How, within a given demographic model, would variable y change if the age- or time-specific function f were to change arbitrarily in shape and intensity? At present demography lacks the machinery to answer this question in analytical and general form. This paper suggests a method based on modern functional calculus for deriving closed-form expressions for the sensitivity of demographic variables to changes in input functions or schedules. It uses this "linkage method" to obtain closed-form expressions for the response of the intrinsic growth rate, birth rate, and age composition of a stable population to arbitrary marginal changes in its age patterns of fertility and mortality. It uses it also to obtain expressions for the transient response of the age composition of a nonstable population to time-varying changes in the birth sequence, and to age-specific fertility and mortality patterns that change over time. The problem of "bias" in period vital rates is also looked at.
The Strategic Triangle: An Elementary Game-Theoretical Analysis

The concept of a“strategic triangle” is useful in an analysis of the internal logic of the relationship between the United States, the Soviet Union, and China. The preconditions for a triangular relationship are that each player recognize the strategic salience of the three principals, and the relationship between any two will be affected by each player's relationship to the third. Within the triangle, there are three distinct pattern dynamics: the menage a trots, consisting of mutually positive relationships among all three; the stable marriage, consisting of a bilateral relationship excluding the third, and the romantic triangle, consisting of one pivot player playing off two suitors. Each of these pattern dynamics has specific rules of rational play. The shift from one pattern dynamic to another is a function of the attempts of the players to freeze a given configuration through commitment to a treaty or a common ideology, interacting with periodic crises that test their commitments.
The Effects of Hermit Crabs on Hydractiniid Hydroids The effects of hermit crabs on hydractiniid hydroids

. Hermit crab shells are often encrusted with diverse communities of epibionts. To explore the effects of hermit crabs on the interactions of these encrusting species, two species of hydractiniid hydroids, Hydractinia symbiolongicarpus and Podocoryna carnea, were examined in the presence and absence of Pagurus longicarpus hermit crabs. Colonies growing on Littorina littorea snail shells with hermit crab hosts were compared to those growing on shells without crabs. These experiments suggest that hermit crabs variably affect colony polyp number, colony morphology and the outcome of interspecific competition, according to the size and number of crabs; other factors include water temperature, food availability and hydroid clonal genotype. In order to allow image analysis of perturbations of colony morphology, hydroids were grown on glass surfaces both exposed and unexposed to hermit crabs. Relative to colonies growing on unexposed surfaces, colonies growing on exposed surfaces exhibited larger within-colony patches, thus decreasing the total encrusted surface area and polyp number of colonies. Further, on glass surfaces, hermit crabs accelerated the time to the resolution of interspecific competition (i.e., the overgrowth of one colony by the other). While a number of factors may contribute to the relative abundance of these encrusting species, under most circumstances P. longicarpus have large effects on hydractiniid hydroids. Mechanisms underlying these effects likely include hydrodynamics and mechanical disturbance.
Investigating the effects of visual saliency on deictic gesture production by a humanoid robot

In many collocated human-robot interaction scenarios, robots are required to accurately and unambiguously indicate an object or point of interest in the environment. Realistic, cluttered environments containing many visually salient targets can present a challenge for the observer of such pointing behavior. In this paper, we describe an experiment and results detailing the effects of visual saliency and pointing modality on human perceptual accuracy of a robot's deictic gestures (head and arm pointing) and compare the results to the perception of human pointing.