cssi/SciSciGPT-SciSciNet huggingface dataset:
Effect of specific siRNA targeting uPAR and MMP-9 in medulloblastoma

Proc Amer Assoc Cancer Res, Volume 47, 2006 4363 The molecular mechanisms underlying the spread of cancer are complex and have only recently begun to be elucidated. In particular, the cellular mechanisms leading to metastatic disease in medulloblastoma (MB), the most common malignant brain tumor in childhood, are mainly unknown. The initial stage of intraspinal spread is characterized by both seeding of tumor cells on the arachnoid or pia mater and the lysis of collagenous barriers to enhance angiogenesis and local invasion, especially extracellular matrix (ECM) degradation. The cooperative expression of a family of adhesion receptors called integrins and cell surface proteinases ( e.g. , uPA, uPAR and MMPs) mediates these angiogenic and invasive processes. A significant association of urokinase plasminogen activator (uPA) and matrix metalloprotease-9 (MMP-9) expression with survival and M-stage indicates that these proteases may modulate the survival of medulloblastoma patients. RNA interference (RNAi) is a conserved mechanism in which double-stranded, small, interfering RNAs (siRNAs) trigger a sequence-specific, gene-silencing process. In this study, we describe the inhibition of urokinase plasminogen activator receptor (uPAR) and MMP-9 using siRNA expression vectors targeted to sequences specific to the coding regions of uPAR (pU) and MMP-9 (pM). We also compare these effects to an expression vector carrying siRNA against both these proteases (pUM). Here, we have targeted uPAR and MMP-9 singly and in combination in vitro to evaluate the anti-invasive and anti-proliferative effects of uPAR and MMP-9 downregulation. We also evaluated these constructs for in vivo anti-tumor activity. MMP-9 and uPAR expression was determined using zymography, western blot, and semiquantitative polymerase chain reaction. Cellular invasion was evaluated using matrigel and spheroid invasion assays. Cell proliferation was determined by MTT assay. Our results demonstrate that the siRNA constructs for uPAR and MMP-9 are capable of specific and functional silencing of gene expression and invasion in vitro in medulloblastoma cells. Moreover, treatment of DAOY meduloblastoma cells implanted orthotopically in mice with the siRNA constructs resulted in significant decreases in tumor size, which translated to increases in survival time. Further analysis of tumors showed that the reduced sizes correlated with a decrease in mean vessel density and an increase in tumor cell apoptosis. Statistical analysis indicates that targeting both uPAR and MMP-9 genes with a single vector demonstrated a clear synergistic effect as compared to targeting either uPAR or MMP-9 alone.
Keeping it Legal: Transboundary Challenges Facing Brazil & the Guarani

This paper examines the legal and ecological problems facing the Guarani Aquifer System. Because the majority of the Guarani Aquifer System underlies Brazil, the Brazilian legal regime forms the paper’s principal focus. The importance of the region makes the need for accurate information crucial. Yet relying on such information to manage a complex resource presents risks. Too often, the role of uncertainty in regulating is underplayed. Increasing knowledge over the resource demands categorizing “hard” and “soft” uncertainties, especially those presented by climate change. In addition, regulators must acknowledge the unitary nature of the aquifer while remaining sensitive to differing national priorities.
The surface potential of and double-layer interaction force between surfaces characterized by multiple ionizable groups.

By considering that the electrostatic charge on biological surfaces arises from the presence of multiple ionizable groups, the surface potential of and double-layer force between two plane surfaces, separated by an electrolyte solution, were evaluated by numerically solving the non-linear Poisson-Boltzmann equation. Boundary conditions were formulated by assuming the groups of the surfaces are always in ionic equilibrium with the solution. Comparisons are made between the force numerically calculated as above and analytical expressions obtained by (a) linearly superimposing the non-interactive electrostatic potential profiles of each surface, or by solving the linearized Poisson-Boltzmann equation with (b) fixed surface potential or with (c) fixed surface charge density. Surface characteristics used for the comparisons were deduced from electrophoretic data on erythrocyte or leucocyte surfaces.
Screening for glucose intolerance in a pediatric multiphasic program.

Venous serum glucose concentrations were obtained 1 hr after ingestion of 37.5 g of carbohydrate during multiphasic screening of 2396 children. Data were analyzed by age group (5–7 yr, 8–10 yr, and 11–13 yr), time of blood sampling (9–11 a.m., 12-2 p.m., and 3–5 p.m.), and duration of fast prior to glucose ingestion (0–3 hr, 4–6 hr, and 7+ hr). As expected with the use of a fixed glucose load, mean serum glucose levels decreased significantly with increasing age—at the <0.05 level between the younger age groups and at the <0.001 level between the early adolescent and the two younger groups. These variations in significance correspond to the more marked ponderal difference between the two preadolescent groups. Time of day of testing was also a significant variable (p <0.001), independent of duration of fast prior to testing. There was no difference between the mean serum glucose following a short (0–3 hr) or a long (7+ hr) fast, but higher mean levels were attained with an intermediate (4–6 hr) fast (p <0.001). The latter corresponds to the growth hormone phase of the postabsorptive period, known to be associated with glucose intolerance. Screening for glucose intolerance as part of a multiphasic program is of little or no value unless the testing variables are controlled or multiple criteria specific for varying testing conditions are applied.
Stress Distribution in an Infinite Shape Memory Alloy Plate with a Circular Hole Subjected to Biaxial Tension

This paper presents an exact solution for the stresses in an infinite shape memory alloy plate with a circular hole subjected to biaxial tensile stresses applied at infinity. The solution obtained by assumption of plane stress is based on the 2D version of the Tanaka constitutive law for shape memory materials. The plate is in the austenitic phase, prior to the application of external stresses. However, as a result of tensile loading, stress-induced martensite forms, beginning from the boundary of the hole and extending into the interior, as the load continues to increase. Therefore, in general case, the plate consists of there annular regions: the inner region of pure martensite, the intermediate region where martensite and austenite coexist, and the outer region of pure austenite. The boundaries between these annular regions can be found as functions of the external stress. Two methods of solution are presented. The first is a closed-form approach based on a replacement of the actual distribution of the martensitic fraction by a piece-wise constant function of the radial coordinate. The second method results in an exact solution obtained by assumption that the ratio between the radial and circumferential stresses in the region where austenite and martensite coexist is governed by the same relationship as that in the encompassing regions of pure austenite and pure martensite.© (1997) COPYRIGHT SPIE--The International Society for Optical Engineering. Downloading of the abstract is permitted for personal use only.
Circumcision as a primary HIV preventive: Extrapolating from the available data

Billions of dollars to circumcise millions of African males as an HIV infection prevention have been sought, yet the effectiveness of circumcision has not been demonstrated. Data from 109 populations comparing HIV prevalence and incidence in men based on circumcision status were evaluated using meta-regression. The impact on the association between circumcision and HIV incidence/prevalence of the HIV risk profile of the population, the circumcision rates within the population and whether the population was in Africa were assessed. No significant difference in the risk of HIV infection based on the circumcision status was seen in general populations. Studies of high-risk populations and populations with a higher prevalence of male circumcision reported significantly greater odds ratios (odds of intact man having HIV) (p < .0001). When adjusted for the impact of a high-risk population and the circumcision rate of the population, the baseline odds ratio was 0.78 (95% CI = 0.56-1.09). No consistent association between presence of HIV infection and circumcision status of adult males in general populations was found. When adjusted for other factors, having a foreskin was not a significant risk factor. This undermines the justification for using circumcision as a primary preventive for HIV infection.
Fast S-inversion In the Time Domain: Method of Interpretation Using the Thin Sheet Approach

Fast S-inversion in the time domain is a method of interpretation of time domain electromagnetic sounding data, using the thin sheet approach. This approach was originally developed in Russia by Sidorov and Tickshaev (1969) and later was introduced independently by Liu and Asten (1993) for conductance-depth imaging of transient EM data. It is based on calculation of the effective conductance S of the equivalent thin sheet, which can be used to determine vertical conductivity profiles of the geoelectrical cross section. In this paper we study two methods of conductancedepth profiles calculation. In the first method, we examine the differential S-transformation of the observed time derivatives of the vertical component of the magnetic field into apparent conductivity. The second method employs a full regularized S-inversion to determine the thin sheet parameters. These two approaches are tested and compared for resolution and reliability on synthetic 3-D models numerically simulated using 3-D EM modeling code SYSEM.
Temporal Dietary Patterns Using Kernel k-Means Clustering

Chronic diseases, such as heart disease, diabetes, and obesity, have been linked with diet. Nutrient intake is also associated with diet. However, much of the research completed to elucidate these associations has not incorporated the concept of time. This paper introduces the concept of temporal dietary patterns and demonstrates a novel construct of 24-hour temporal dietary patterns for energy intake, present in a sample of the adult U.S. population 20 years and older (NHANES 1999-2004 dataset). An appropriate distance metric is proposed for comparing 24-hour diet records and is used with kernel k-means clustering to identify the temporal dietary patterns.
Neglected Parasitic Infections and Poverty in the United States

The neglected tropical diseases (NTDs) are a group of chronic and disabling infections that occur primarily in settings of extreme poverty and affect over 1,000,000,000 people globally [1]. A selected group of neglected parasitic infections, including some which overlap with the World Health Organization's new list of recognized NTDs [2], are also common in the United States, where they disproportionately affect the poor. The major neglected parasitic infections in the US include Chagas disease, cysticercosis, toxocariasis, toxoplasmosis, and trichomoniasis. These five parasitic infections are considered “neglected” based on their high prevalence, chronic and disabling features, and their strong links with poverty [1], [2]. In contrast, the major intestinal parasitic infections found in the US—cryptosporidiosis, cyclosporiasis, and giardiasis—are mostly acute diarrheal illnesses without significant links to poverty or neglected populations. This review highlights new information (mostly from the last five years) on the major neglected parasitic infections affecting impoverished Americans, with respect to their distribution and unique clinical presentations as well as their surprising links to cardiovascular, respiratory, and neuropsychiatric conditions ordinarily thought of as noncommunicable diseases. Key diagnostic and therapeutic challenges and urgent needs for active surveillance and prevention are also presented.
SCF-Xα-SW calculations for small molecules using the optimization technique of atomic-sphere radii

Abstract SCF-Xα-SW calculations of structure parameters, normal-stretching-vibration frequencies and ionization energies of the small molecules N 2 , O 2 , F 2 , CO, CH 2 and NH 3 have been performed using the atomic-sphere radii determined by a technique previously proposed on the basis of optimization of the virial theorem and minimization of total energy. The effectiveness of this optimization technique in the SCF-Xα-SW method has been confirmed by the improved agreement between the calculations and experimental data for all the cases. An extension of this technique to more complicated molecules is discussed using the H 2 CO molecule as a test example.
Chronic Myeloid Leukemia: Current Application of Cytogenetics and Molecular Testing for Diagnosis and Treatment

Chronic myeloid leukemia provides an illustrative disease model for both molecular pathogenesis of cancer and rational drug therapy. Chronic myeloid leukemia is a clonal stem cell disease caused by an acquired somatic mutation that fuses, through chromosomal translocation, the abl and bcr genes on chromosomes 9 and 22, respectively. The bcr/abl gene product is an oncogenic protein that localizes to the cytoskeleton and displays an up-regulated tyrosine kinase activity that leads to the recruitment of downstream effectors of cell proliferation and cell survival and consequently cell transformation. Such molecular information on pathogenesis has facilitated accurate diagnosis, the development of pathogenesis-targeted drug therapy, and most recently the application of molecular techniques for monitoring minimal residual disease after successful therapy. These issues are discussed within the context of clinical practice.
A Right to Benefit from International Research: A New Approach to Capacity Building in Less-Developed Countries

This article proposes a means by which benefits provided in international research collaborations might be employed to strengthen health care, research, and other capacities in less-developed countries. The Declaration of Helsinki and CIOMS Guidelines define certain expectations of benefits, but these requirements are ambiguous, logistically problematic, and studies suggest they are inconsistently upheld. Drawing on the principle of respect for persons, a right to benefit from hosting externally-sponsored research is proposed. This right guarantees host communities benefits of a certain value, the nature and use of which is controlled by indigenous personnel. Suggestions are made as to how implementation of this right, using structured incentives, may systematically promote capacity building in host communities.
Response of Human Oligodendrocytes to Interleukin-2

Interleukin 2 (IL-2) directly affects the function of both neurons and glia in the nervous system. It can induce proliferation and differentiation or cause cell death in oligodendrocytes. We have previously cloned the cDNAs for the alpha (alpha), beta (beta), and gamma (gamma) chains of the IL-2 receptor (IL-2R) complex from a human oligodendroglioma cell line TC620. In an effort to characterize the IL-2 receptor (IL-2R) on oligodendrocytes, experiments were performed using recombinant human IL-2 on normal human oligodendrocytes from adult brain tissue and the IL-2-responsive subclone TC620.6A2 of the oligodendroglioma line. The TC620 subclone has the phenotype of an immature oligodendrocyte. At 5 nM IL-2, there was a 2.5-fold increase in proliferation of both normal and malignant human oligodendrocytes. This response was receptor-mediated in that binding of 125I-IL-2 to TC620.6A2 cells detected a single receptor class for IL-2 with an affinity of 3.6 nM. Immunohistochemical staining of TC620.6A2 cells with a panel of monoclonal antibodies to different epitopes of the human IL-2R alpha chain demonstrated the presence of IL-2R alpha on the surface of these cells, in staining patterns which did not always coincide with those found on T cells. Neither the beta nor the gamma chain of the IL-2R complex was detected on human oligodendrocytes by immunohistochemistry. Those antibodies which recognized cell surface IL-2R alpha epitopes on TC620.6A2 blocked IL-2-induced proliferation, while those which did not detect cell surface IL-2R alpha epitopes were not inhibitory. This same panel of monoclonal antibodies, when used to probe membrane preparations of TC620.6A2 cells on a Western blot, detected three proteins of 100, 83, and 47 kDa, in contrast to the 55-kDa IL-2R alpha observed on T cells.
Microbial diversity and activity of disturbed soil in the northern Chihuahuan Desert

The effects of intense grazing, seasonal drought, and fire on soil microbial diversity (substrate utilization) and activity in a northern Chihuahuan Desert grassland were measured in summer 1997, winter 1998, and spring 1998. Intense livestock grazing was initiated in winter 1995, burning occurred in August 1994, and drought stresses were imposed from October 1994 to June 1997. Microbial diversity was inferred from the carbon substrate utilization patterns in both gram (+) and gram (–) Biolog plates. Microbial activity was estimated by the activity of selected enzymes. Neither microbial diversity nor activity was affected by grazing. The interaction of intense grazing and stress sub-treatments only occurred in spring for one set of diversity measurements. The maximum microbial diversity and activity occurred in the winter-drought-stress sub-plots in summer and spring. Burning reduced microbial diversity and most enzyme activities as compared to the control in summer and spring. Microbial diversity was also lower in summer-drought-stress sub-plots than in the control in summer and spring. Microbial diversity was highest in summer, intermediate in winter, and lowest in spring. Microbial activity was generally higher in summer and lower in winter. It was concluded that substrate availability was the most important factor affecting the diversity and activity of soil microorganisms within a season. Soil moisture was not the factor causing differences in microbial diversity and activity among the stress treatments, but it was a predictor for some microbial responses under a particular stress.
Cochlear and middle ear effects on metabolism in the central auditory pathway during silence: A 2-deoxyglucose study

Abstract The [14C]2-deoxy- d -glucose (2-DG) autoradiographic technique was used to investigate metabolic activity in the central auditory pathways during silence. Relative 2-DG uptake was assessed in silence for three groups of Mongolian gerbils: control animals; those with unilateral cochlear ablations, and those with unilateral conductive hearing losses. Control subjects showed no differences between the two sides of their central auditory pathways. Subjects with unilateral cochlear ablations showed markedly lower 2-DG uptake in the major afferent projection pathway from the ablated cochlea compared with 2-DG uptake in contralateral structures. That is, relative 2-DG uptake was significantly lower ipsilateral to the ablation in the anteroventral and dorsal cochlear nuclei, and contralateral to the ablation in the ventral nucleus of the lateral lemniscus, the dorsal nucleus of the lateral lemniscus, and the inferior colliculus. No effect of ablation was seen in the superior olivary complex, the medial geniculate nucleus or the auditory cortex. Subjects with a unilateral conductive hearing loss, unexpectedly, showed significantly higher 2-DG incorporation in the major afferent projection from the impaired side. That is, relative 2-DG uptake was higher in the anteroventral cochlear nucleus, the dorsal cochlear nucleus and the lateral superior olivary nucleus ipsilateral to the hearing loss, and in the dorsal nucleus of the lateral lemniscus contralateral to the hearing loss. These increases in 2-DG uptake following conductive hearing loss represent a mechanism which may account for clinical hearing disorders such as tinnitus. It is concluded that, even under conditions of silence, the intact cochlea and middle ear conductive apparatus significantly influence metabolic activity in the central auditory pathway up through the level of the inferior colliculus.
Economic Knowledge and High School Student Attitudes toward the American Economic System, Business, and Labor Unions

(1983). Economic Knowledge and High School Student Attitudes toward the American Economic System, Business, and Labor Unions. Theory & Research in Social Education: Vol. 11, No. 3, pp. 1-15.
Role of nitric oxide synthase in collagen-platelet interaction: involvement of platelet nonintegrin collagen receptor nitrotyrosylation.

Abstract Platelets possess the endothelial isoform of nitric oxide synthase (eNOS), which plays an important role in platelet function. Other laboratories, including ours, have reported that nitric oxide (NO) is released upon exposure of platelets to collagen, but the mechanism of the interaction is not yet established. The objective of this study is to examine the possible role of nonintegrin receptor nitrotyrosylation on collagen-induced platelet aggregation. Results of the study show that two platelet proteins with M r of 65- and 23-kDa proteins are nitrotyrosylated in a time-dependent manner after the addition of type I collagen. The M r 65-kDa protein is identified as the platelet receptor for type I collagen. The recombinant protein of the platelet receptor for type I collagen can also be nitrotyrosylated. The nitrotyrosylated recombinant protein loses its ability to inhibit type I collagen-induced platelet aggregation. In addition, the polyclonal anti-65 kDa immunoprecipitates eNOS suggesting that the platelet nonintegrin receptor for type I collagen is closely linked to the eNOS. These results demonstrate that the inhibitory effect of NO on collagen-induced platelet aggregation may be mediated by the nitrotyrosylation of the 65-kDa receptor.
Alcohol Policies and Free to Be Foolish: An Analysis of College Students

A convenience sample of 472 undergraduate students from a large public university in the Midwest was surveyed with regard to their views on consumption of alcohol as a personal privilege and related policies on alcohol use. The sample of predominantly white students was divided between 239 libertarians and 192 supporters of collective responsibility. Compared with their collective peers, the libertarian students were younger, heavier consumers of alcohol, and more likely to be male. The libertarian students were opposed to external sanctions on drinking behavior regardless of source of authority. Intervention programs such as server training implemented by the students themselves were, however, supported by both groups. The potential for achieving wider low risk alcohol use through server training programs is considered in the context of campus and campus town life. Although promotion of such programs has potential for positive change, administrators must recognize the potency of the world view of "free to be foolish" and broader external forces when seeking a comprehensive needs-based approach to program planning.
Use of Individual Flight Corridors to Avoid Vortex Wakes

Vortex wakes of aircraft pose a hazard to following aircraft until the energetic parts of their flow fields have decayed to a harmless level. It is suggested here that in-trail spacings between aircraft can be significantly and safely reduced by designing an individual, vortex-free flight corridor for each aircraft. Because each aircraft will then have its own flight corridor, which is free of vortex wakes while in use by the assigned aircraft, the time intervals between aircraft operations can be safely reduced to the order of seconds. The productivity of airports can then be substantially increased. How large the offset distances between operational corridors need to be to have them vortex free, and how airports need to be changed to accommodate an individual flight-corridor process for landing and takeoff operations, are explored. Estimates are then made of the productivity of an individual flight-corridor system as a function of the in-trail time interval between operations for various values of wake decay time, runway width, and the velocity of a sidewind. The results confirm the need for short time intervals between aircraft operations if smaller offset distances and increased productivity are to be achieved.
A heuristic solution procedure for multicommodity integer flows

This paper presents a heuristic method to determine integer-valued solutions for the multicommodity maximal flow and minimum cost flow problems. It is well known that for single commodity flow problems the optimal solutions are integer-valued provided the necessary data (capacities, supplies, demands) are integers. However, the presence of mutual arc capacity restrictions that limit the total flow of all commodities along each arc destroy the integrality property for multicommodity flow problems. The proposed heuristic first determines an initial integer-valued solution by dividing the common capacity on each arc among the commodities and decomposing the problem into single commodity flow problems one for each commodity. The heuristic then attempts to reallocate the capacity, one arc at a time, using parametric analysis and the corresponding dual variable information to search for better solutions. An application of the multicommodity minimum cost integer flow problem to the equipment replacement problem and computational experience for the proposed heuristic are also discussed.
Coherence effects on the phase accuracy of an optical Fourier processor

Interference techniques can be used to measure both the amplitude and phase of optically generated Fourier transforms. Because phase information is recovered by observing an interference pattern, source coherence can significantly influence phase accuracy. System performance is analyzed using simple test functions and the phase error is estimated in terms of the source transverse coherence length and space-bandwidth product of the input function.
A quantification of policy reform: an application to the Uruguay Round Negotiations on Agriculture

Abstract We employ an empirical general equilibrium model to quantify the welfare effects of trade policy reformation in the Uruguay Round Negotiations on Agriculture. Our approach is two-fold: first we focus on the primary players in the agricultural negotiations: the Cairns Group, the European Union, Japan, and the United States, where the players are defined as benevolent governments whose primary objective is to maximize total welfare, measured in terms of the equivalent variation (EV). Second, we take into account the divergent objectives of different interest groups within the targeted regions, namely from the agricultural and non-agricultural sectors, where different weights given to these sectors depending on their political influence. Here the decision making authorities, or governments, are no longer assumed to focus solely on the maximization of the region’s EV welfare; instead they are assumed to maximize a payoff that is defined by the utilities of the agricultural and non-agricultural interest groups. This is modeled with a Political Preference Function that has a CES functional form. The results lead to several conclusions. The greater the reduction in protection, the greater the increase in welfare for most of the regions of the world. We contend that comparatively moderate reductions were enacted however, because of the relative political power that the domestic agricultural interests possessed in each region. Though the goal of the WTO/GATT is obviously to liberalize trade, only modest gains may be expected in the area of agriculture due to the internal conditions that have been advanced in this paper.
M-Current suppression in PC 12 cells by bradykinin is mediated by a pertussis toxin-insensitive G-protein and modulated by intracellular calcium

Inhibition of the M-current in PC12 cells by bradykinin has been studied under whole-cell recording conditions. In cells dialyzed with GTP-gamma-S, bradykinin produced a total and irreversible M-current suppression, while the inhibition was attenuated in cells dialyzed with GDP-beta-S. Inhibition occurred in cells pretreated with pertussis toxin, while this treatment prevented the modulation of Ca2+ currents by muscarine. The rate and extent of inhibition increased with the level of intracellular Ca2+ from 0 to 70 nM. These results indicate that a pertussis toxin insensitive G-protein mediates the action of bradykinin on the M-current, and some steps in the second messenger cascade are modulated by Ca2+.
Comparing the Health Locus of Control among Caucasian and Hmong College Students

The fourth largest population of Hmong in the United States resides in western North Carolina. Before their exposure to western medicine, the Hmong relied solely on shamans (ua neeb saib), or spiritual healers, and herbal medicine for health needs. This study compares the health locus of control among Hmong and Caucasian students using the Multi-Dimensional Health Locus of Control Scale. College students participated anonymously by email and social media utilizing a web-based survey. Based on rapid acculturation of Hmong families and social pressure to adopt a “college lifestyle,” we predict differences between subscales of Hmong and Caucasian College students.
Radion dynamics and electroweak physics

The dynamics of a stabilized radion in the Randall-Sundrum model with two branes is investigated, and the effects of the radion on electroweak precision observables are evaluated. The radius is assumed to be stabilized using a bulk scalar field as suggested by Goldberger and Wise. First the mass and the wave function of the radion is determined including the back reaction of the bulk stabilization field on the metric, giving a typical radion mass of the order of the weak scale. This is demonstrated by a perturbative computation of the radion wave function. A consequence of the background configuration for the scalar field is that after including the back reaction the Kaluza-Klein states of the bulk scalars couple directly to the standard model fields on the TeV brane. Some cosmological implications are discussed, and in particular it is found that the shift in the radion at late times is in agreement with the four-dimensional effective theory result. The effect of the radion on the oblique parameters is evaluated using an effective theory approach. In the absence of a curvature-scalar Higgs mixing operator, these corrections are small and give a negative contribution to S. In the presence of such a mixingmore » operator, however, the corrections can be sizable due to the modified Higgs and radion couplings.« less
Inhibition of free radical induced chromosomal aberrations in vitro by alpha-tocopherol

Abstract The antioxidant, alpha-tocopherol (Vitamin E), inhibited chemically induced chromosomal aberrations in Chinese hamster (DON) cells in vitro. Addition of alpha-tocopherol to cell cultures 48 hours prior to induction of chromosomal abnormalities by 2,2,6,6-tetramethyl-4-oxo-piperidin-1-oxyl (TEMPONE) produced inhibition of induced chromosomal alterations. TEMPONE is a free radical that has been demonstrated to induce chromosomal damage in vitro. These data suggest that Vitamin E molecules already present in the cell cultures may react immediately with the free radicals, resulting in less free radical damage to macromolecules in the cells.
Critical configurations of systems subjected to wide-band input

Abstract It is well known that the response of harmonically loaded structures can be sensitive to small variations in the structure's parameters. For instance, if a change in a parameter causes a natural frequency to become tuned to the input frequency, the response will exhibit a resonance peak. This paper explores the possibility of sensitive response patterns when the input is wide-band. It was found that large increases or reductions in the mean-square response can occur when two or more natural frequencies are closely spaced. Closed form expressions are derived to characterize these response fluctuations. The results show that sensitive response patterns are associated with significant correlation between model responses, as well as veerings and crossings of natural frequencies.
A singular perturbation-finite element procedure for the analysis of structures with a small bending rigidity

Abstract A finite element formulation for structural problems chaacterized by small bending rigidities is proposed. In this formulation physically appropriate shape functions are developed using singular perturbation methods. These shape functions account for the effects of applied element pressure. The developed shape functions can be used to solve structural problems involving cables, plates, and shells. Numerical results are presented. These numerical results demonstrate the improved behavior of the new shape functions compared to the Hermitian shape functions.
Preliminary evaluation of energy consumption in China's agriculture — Analysis of two specific cases

Abstract The present status and the perspective of the energy consumption in China's agriculture, with emphasis on crop production, was discussed based on nation-wide statistics as well as two specifically investigated production units. It was estimated that about 17.2% of China's commercial energy was consumed in the rural area in 1978. Commercial energy used in crop production was estimated as 7.3% of the energy input of the whole country. Chemical fertilizer has been and will still be, in the near future, the major energy expenditure in China's crop production. In the two investigated units, the energy input level for crop production has reached that of the industrialized countries. The average level of the whole country, however, is still at a relatively low level of about 1.2 × 10 7 kJ/ha. As a first step to modernize China's agriculture, it appears that an additional commercial energy input of 8.7 × 10 14 kJ would be needed. Approaches to solving the energy problems in China's rural area are discussed briefly.
Viruses and microRNAs: RISCy interactions with serious consequences

Analyses of small RNA expression profiles have revealed that several DNA viruses—including particularly, herpesviruses—express high levels of multiple viral microRNAs (miRNAs) in infected cells. Here, I review our current understanding of how viral miRNAs influence viral replication and pathogenesis and discuss how viruses reshape the pattern of cellular miRNA expression. Indeed, viruses are now known to both activate and repress the expression of specific cellular miRNAs, and disrupting this process can perturb the ability of viruses to replicate normally. In addition, it is now clear that virally encoded miRNAs play a key role in inhibiting antiviral innate immune responses and can also promote cell transformation in culture. While our understanding of how viruses interact with miRNAs remains somewhat rudimentary, it is nevertheless already clear that these interactions can play a critical role in mediating viral pathogenesis and therefore may represent novel and highly specific targets for therapeutic intervention.
Secondary transmission of nuclear polyhedrosis virus by Pseudoplusia includens and Anticarsia gemmatalis Larvae on semisynthetic diet

Abstract Secondary transmission of nuclear polyhedrosis viruses of the soybean looper, Pseudoplusia includens (SLNPV), and velvetbean caterpillar, Anticarsia gemmatalis, in their respective hosts on semisynthetic diet was examined. Mortality of test P. includens larvae (untreated), reared together on diet with SLNPV-treated (primary infected) P. includens larvae (at all sizes), was higher than in test A. gemmatalis larvae reared with primary infected A. gemmatalis larvae. Removal of primary infected larvae from rearing containers within 24 hr of death resulted only in low mortality levels in the test larvae of both species. Larval mortality of both species increased with the length of time that larvae were exposed to cadavers of primary infected larvae. In both species mortality differed with size of untreated larvae, size at death of primary infected larvae, and stage of disease in primary infected larvae when they were placed with the untreated larvae. However, the effect of each factor on secondary transmission differed somewhat with insect species.
Numerical p-version refinement studies for the regularized stress-BEM

In the development of the boundary element method (BEM) and the finite element method (FEM) researchers have typically selected similar basis functions. That is, both methods typically employ low-order interpolations such as piece-wise linear or piece-wise quadratic and rely on h-version refinement to increase accuracy as required. In the case of the FEM, the decision to use low-order elements is made for computational efficiency as an attractive compromise between local modeling accuracy and sparseness of the resulting linear system. However, in many BEM formulations, low-order elements may be the only practical choice given the complexity of using analytic integration formulae in conjunction with special integral interpretations. Unlike their efficient use in the FEM, fine meshes of low-order elements in the BEM are highly inefficient from a computational standpoint given the dense nature of BEM systems. Moreover, owing to singularities in the kernel functions, the BEM should be expected to benefit more so than the FEM from very high levels of local accuracy. Through the use of regularized algorithms which only require numerical integration, p-version refinement in the BEM is easily extended to include any set of basis functions with no significant increase in programming complexity. Numerical results show that by using interpolations as high as 12th and 16th order, one can expect reductions in error by as many as five orders of magnitude over comparable algorithms based on similar system size. For two-dimensional problems, it is also shown that, for a given level of error, one can expect reductions in system size by an order of magnitude, thus leading to a reduction in computational expense for conventional algorithms by three orders of magnitude. Copyright © 2003 John Wiley & Sons, Ltd.
“Dreadful thoughts”: The tenth anniversary of the Levin petition

I n 1988, Richard Levin, Professor of English at the State University of New York at Stony Brook, wrote an essay for the Publications of the Modem Language Association (PMI-4) explaining his objections to feminist literary criticism. The react ion f rom feminist literary critics that ensued revealed how politicized literary scholarship had become dur ing the 1970s and 1980s and how literary theory was transforming into political activism. It has been ten years since the feminist literary critics launched their assault on Professor Levin, and it would be enl ightening to revisit the tactics in tended to int imidate literary scholars who failed to acknowledge the political goals of radical academics. It is hard to measure what success, if any, feminist literary critics were able to realize f rom their attack on Professor Levin, but it surely must have been more than apparent ten years ago to n o n t e n u r e d literature teachers, graduate students, and depar tment cha i rmen that scholars risked the oppor tuni ty to publish if they dared, like Professor Levin, to find fault with feminist literary criticism. In his essay, titled "Feminist Thematics and Shakespearian Tragedy," Levin argued that feminist literary criticism, since it emerged dur ing the mid-1970s, suffered from an overreliance on thematics, the reduct ion of complex works of literature to a handful of simple and persistent themes.1 (Such an objection was consistent with Professor Levin's similar complaints in his 1979 New Readings vs. Old Plays that thematic studies deprive Shakespeare's plays of their complexity and originality. For the thematic critic, Professor Levin argued, the significance of Shakespeare's plays always resides e lsewhere-in contemporary documents , religious controversies, or topical events -but no t in the words that Shakespeare wrote.) In his PMIA essay, Professor Levin similarly observed that "the themes employed in [feminist] interpretat ions are basically the same. Although the terminology may vary, these criticisms all f ind that [Shakespeare's] plays are about the role of gender in the individual and society" (125). Insisting that Shakespeare's plays are really about gender themes not only obscures o ther and richer interpretations, Professor Levin argued, but feminist literary critics too often ignore the facts of the plays. For example, Professor Levin cited one feminist literary critic who wrote that King Lear's rejection of his daughter in the first act of King Lear is a social n o r m for the patriarchal father-daughter relationship. Yet, observed Levin, "the witnesses to this relat ionship--Kent, Gloucester, Burgundy, France, even Goneril and
Rare-earth-rich tellurides: Gd4NiTe2 and Er5M2Te2 (M=Co, Ni)

Abstract Three new rare earth metal-rich compounds, Gd4NiTe2, and Er5M2Te2 (M=Ni, Co), were synthesized in direct reactions using R, R3M, and R2Te3 (R=Gd, Er; M=Co, Ni) and single-crystal structures were determined. Gd4NiTe2 is orthorhombic and crystallizes in space group Pnma with four formula units per cell. Lattice parameters at 110(2) K are a = 15.548 ( 9 ) , b = 4.113 ( 2 ) , c = 11.7521 ( 15 ) A . Er5Ni2Te2 and Er5Co2Te2 are isostructural and crystallize in the orthorhombic space group Cmcm with two formula units per cell. Lattice parameters at 110(2) K are a = 3.934 ( 1 ) , b = 14.811 ( 4 ) , c = 14.709 ( 4 ) A , and a = 3.898 ( 1 ) , b = 14.920 ( 3 ) , c = 14.889 ( 3 ) A , respectively. Metal–metal bonding correlations were analyzed using the empirical Pauling bond order concept.
Effect of Compositional Short Range Order on Glass Formation in Binary Metallic System

Abstract : Molecular Dynamics simulation was carried out to study the glass transition and crystallization in the metal-metalloid binary system with pair-wise potentials. The results show that a repulsive potential between metalloid (small) atoms increases the glass forming ability. The observation is consistent with the recent theory of bulk metallic glass formation through local glass transition and nano-glass formation. The theory predicted that the compositional short-range order (CSRO) prevents the small atom pairing so as to increase the glass forming ability (GFA). The present results demonstrate the important role of CSRO in bulk metallic glass formation.
Effects on optical systems from interactions with oxygen atoms in low earth orbits

Modifications of material surface properties due to interactions with ambient atomic oxygen have been observed on surfaces facing the orbital direction in low earth orbits. Some effects are very damaging to surface optical properties while some are more subtle and even beneficial. Most combustible materials are heavily etched, and some coatings, such as silver and osmium, are seriously degraded or removed as volatile oxides. The growth of oxide films on metals and semiconductors considered stable in dry air was measured. Material removal, surface roughness, reflectance, and optical densities are reported. Effects of temperature, contamination, and overcoatings are noted.
Coevolution of self-fertilization and inbreeding depression. III. Homozygous lethal mutations at multiple loci.

Abstract We study the evolution of the rate of self-fertilization in response to deleterious mutations at multiple loci. Although partial selfing induces associations among loci even in the absence of linkage, associations among mutations at different loci are of a smaller order of magnitude than the mutation rate. Genotypes that carry homozygous lethal mutations in heterozygous form at i loci occur in frequencies of the order ( T i ) μ i , in which T denotes the number of viability loci and μ the mutation rate. While associations between mutations at different loci remain small even under inbreeding, each viability locus develops an association with the modifier of the rate of self-fertilization that substantially affects the evolution of the breeding system. Positive associations between enhancers of selfing and haplotypes carrying multiple wild-type alleles and positive associations in heterozygosity between the modifier locus and the viability loci promote evolutionary increases in the rate of self-fertilization.
3-Oxotetrahydrothiophen-1,1-dioxide A Versatile Synthetic Intermediate

Abstract An improved preparation and valuable new reactions of 3-oxotetra-hydrothiophen-1,1-dioxide are described.
Public support for punishing white-collar crime: Blaming the victim revisited?

Abstract It is commonly asserted that white-collar crime flourishes because the public is unaware of its costs and indifferent to its control. Survey data collected in Illinois indicate, however, that the public perceives white-collar offenses to have greater economic and moral costs than conventional street crimes, though not to be as violent. More notably, our sample displayed strong support for the criminal sanctioning of white-collar offenders. Public attitudes thus do not appear to be either a major obstacle to attacking upper-world criminality, or its source. It is suggested that attempts to blame the public for its immense victimization serve only to divert attention from the real structural conditions that underlie both high rates of white-collar crime and the reluctance of the state to bring the lawlessness of the advantaged within the reach of the criminal law.
Studies on Morinda citrifolia L. II

The results of a study of the anatomy of the stem of Morinda citrifolia L. are described. A preliminary report of the pharmacodynamic study of a 95 per cent alcoholic extract of the root on the isolated uterine horn of an albino rat showed some measure of sedation using doses of 1 to 5,000 to 1 to 36,000. A water decoction of the crude whole root, injected intravenously in the anesthetized dog, in a dose representing 4 Gm. produced a marked lowering of blood pressure which lasted approximately twenty-six minutes. It appears that the hypotensor activity resides in the water-soluble fraction of the root of Morinda citrifolia . The results of in vivo experiments gave evidence of a low order of toxicity of Morinda citrifolia root.
Clinical Applications Of A Quantitative Analysis Of Regional Left Ventricular Wall Motion

Observations were summarized which may have clinical application. These were obtained from a quantitative analysis of wall motion that was used to detect both hypokinesis and tardokinesis in left ventricular cineangiograms. The method was based on statistical comparisons with normal values for regional wall motion derived from the cineangiograms of patients who were found not to have heart disease.
A finite-element model for the analysis of thick, Anisotropic, Bimodular, Fibrous-composite plates

Abstract A finite-element model is developed to analyze the behavior of a shear-deformable, bimodular, anisotropic plate with a uniform rectangular cross-section. The effect of shear-deformation is taken into account by assuming a linear variation for normal strains through the thickness of the plate. Results for transverse deflection and position of neutral surface are presented for a simply-supported plate under uniformly distributed load. The bending behavior is studied for different angles of fiber orientation, plate aspect ratios, and bimodularity ratios.