cssi/SciSciGPT-SciSciNet huggingface dataset:
Metabolism of Methionine and Methionine Hydroxy Analogue by Porcine Kidney Fibroblasts

Porcine kidney fibroblasts in culture are able to utilize the 2-hydroxy analog of methionine (MHA) as the sole methionine source, but higher concentrations of MHA than methionine are required. The optimal concentration for growth with L-methionine ranges from 0.02 to 1.0 mM, whereas that for DL-MHA is 7.5 mM. At concentrations above 1.0 mM, L-methionine exhibits a toxic effect. Supplementing 1.0 mM L-methionine with DL-MHA allows greater growth than that provided by an equimolar concentration of L-methionine alone, and no toxic effect is seen at methionine source (DL-MHA) concentrations up to 7.5 mM. Early in the growth phase of cells where DL-MHA is the sole source of methionine, a 48-h lag period is observed over that seen in cells grown in the presence of 1.0 mM L-methionine. After the lag period, the MHA-supplemented cells double at the same rate as the methionine-supplemented cells. Studies with the purified isomers of D- and L-MHA indicate that only the D-isomer is utilized by these fibroblasts.
Tracheal mucociliary transport in patients with cystic fibrosis and its stimulation by terbutaline.

Tracheal mucous velocity was measured by observing the motion of teflon discs across the tracheal mucosa through a fiberoptic bronchoscope. The average rate of movement in 14 adult patients with cy...
The exomer cargo adaptor structure reveals a novel GTPase-binding domain

Cargo adaptors control intracellular trafficking of transmembrane proteins by sorting them into membrane transport carriers. The COPI, COPII, and clathrin cargo adaptors are structurally well characterized, but other cargo adaptors remain poorly understood. Exomer is a specialized cargo adaptor that sorts specific proteins into trans-Golgi network (TGN)-derived vesicles in response to cellular signals. Exomer is recruited to the TGN by the Arf1 GTPase, a universally conserved trafficking regulator. Here, we report the crystal structure of a tetrameric exomer complex composed of two copies each of the Chs5 and Chs6 subunits. The structure reveals the FN3 and BRCT domains of Chs5, which together we refer to as the FBE domain (FN3–BRCT of exomer), project from the exomer core complex. The overall architecture of the FBE domain is reminiscent of the appendage domains of other cargo adaptors, although it exhibits a distinct topology. In contrast to appendage domains, which bind accessory factors, we show that the primary role of the FBE domain is to bind Arf1 for recruitment of exomer to membranes.
Object-oriented neural networks in C++

Introduction. Object-Oriented Programming Review. Neural-Network Base Classes. ADALINE Network. Backpropagation Neural Network. Self-Organizing Neural Network. Bidirectional Associative Memory. Appendixes. Subject Index.
ASYMPTOTIC NORMALITY OF A NONPARAMETRIC INSTRUMENTAL VARIABLES ESTIMATOR

This article gives conditions under which the nonparametric instrumental variables estimator of Hall and Horowitz (Annals of Statistics 33 (December 2005), 2904–2929) is asymptotically normally distributed. With sufficiently large samples, the asymptotic normality result can be used to form confidence intervals for the unknown function that is estimated by the Hall–Horowitz procedure. The article reports the results of a Monte Carlo investigation of the finite-sample coverage probabilities of the confidence intervals.
Refactoring for Asynchronous Execution on Mobile Devices

To improve responsiveness, developers often use asynchronous programming. In the post-PC era, asynchronous programming is even more in demand because mobile and wearable devices have limited resources and access the network excessively. One current development task is refactoring long-running, blocking synchronous code (for example, accessing the Web, a cloud, a database, or a file system) into nonblocking asynchronous code. This article describes the refactorings that improve responsiveness, along with the obstacles of using asynchrony. It also discusses the challenges of retrofitting asynchrony and presents program analyses and transformations and a growing, practical toolset and resources for retrofitting asynchrony. This article is part of a special issue on Refactoring.
Possible magnetic-field-induced voltage and thermopower in diluted magnetic semiconductors

In diluted magnetic semiconductors, the carrier concentration and the magnetization of local moments are strongly coupled, since the magnetic interaction is mediated by the carriers. It is predicted that this coupling leads to an electric polarization due to an applied magnetic-field gradient and to the appearance of a magnetic-field-dependent voltage. An expression for this voltage is derived within Landau theory and its magnitude is estimated for $(\mathrm{Ga},\mathrm{Mn})\mathrm{As}$. Furthermore, a large contribution to the thermopower based on the same mechanism is predicted. The role of fluctuations is also discussed. These predictions hold both if the magnetization is uniform and if it shows stripelike modulations, which are possible at lower temperatures.
Examining the facilitators and barriers faced by adoptive professionals delivering post-placement services

Abstract Most studies focusing on the delivery of post-adoption services and resources have focused on adoptive parents' perceptions and feelings. However, the experiences of adoption professionals have been largely left out of this discussion. This pilot study attempted to close this gap by asking a sample of adoption professionals to describe the barriers that hinder adoptive families from accessing post-placement treatment and support services, and how these can be overcome. Participants rated the responses to each question on its importance, and how well they thought adoption professionals had addressed it. Concept mapping, a mixed-method approach, was used to analyze participants' responses. Scaled data were analyzed to test for statistically significant differences between the importance of each statement and how well adoption professional had addressed them. The differences between all aggregate ratings were statistically significant, illustrating the great need for adoption professionals to better work with adoptive families to improve service accessibility. Thematic analyses indicated that most barriers were at the macro-level, and that macro level barriers were worse addressed than micro-level barriers. The study identified new barriers such as “appearance of perfection” and new dimensions of worker discontinuity and service inequity barriers. Implications for the field and further research are discussed.
Polyhedral convex feasible regions in stochastic programming with recourse

Multistage stochastic programming with recourse is formulated in terms of a recursive sequence of mathematical programming problems--P0,..., PK--with stochastic data. A polyhedral property of their feasible regions is used to derive a Lipschitz property of their objective functions. A slightly stronger property is used to conclude that any measurable decision rule satisfying the explicit and Implicit constraints of Pk(0 ? k ? K) almost surely can be redefined on a set of measure 0 so it satisfies the constraints for every possible realization of the random variables. Sufficient conditions for each of the two polyhedral convexity properties are given.
Latent Heat-of-Fusion Energy Storage: Experiments on Heat Transfer from Cylinders During Melting

Melting from an array of three staggered, electrically heated cylinders imbedded in a paraffin (n-octadecane) has been studied. The shape of the melting front has been determined photographically, and the local heat transfer coefficients were measured using a shadowgraph technique. The experiments provide conclusive evidence of the important role played by natural convection on the timewise variation of the melt shape, the surface temperature and the instantaneous local as well as circumferentially averaged heat transfer coefficients around the imbedded heat sources. After a common solid-liquid interface is formed around the cylinders, natural convection circulation around each cylinder interacts strongly with the other two cylinders. The arrangement of heat sources affects significantly the melt shape but the circumferentially averaged instantaneous heat transfer coefficients differ only by about 10 percent for the two arrangements studied. The experimental findings indicate that natural convection effects are important and should be considered in analysis and design of systems involving phase change.
The synthesis of fluorescent penicilloyl haptens and their use in investigating ‘penicillin’ antibodies by fluorescence polarization

Abstract Methods for the synthesis and purification of fluorescent penicilloyl haptens are presented. These haptens combine specifically with anti-penicilloyl antibodies from rabbits or humans and can be used to determine antibody concentration and binding affinity by fluorescence polarization. Large differences in binding affinity have been found in the antibodies from different human sera. These results suggest a detailed study of antibody parameters in the various immunoglobulin fractions as related to clinical symptoms of penicillin allergy.
A summer course for gifted high school students

This paper describes a project conducted during the summer of 1981 at the University of Central Florida. Through the Governor's Office of the State of Florida, funds were identified for several state universities to support gifted high school students in summer programs. Such Governor's Programs for gifted students have been done in a number of other states before, most notably Virginia (see [1] and [2]), but this was only the second such program in the State of Florida, and the first at the University of Central Florida. High school students were selected from the surrounding geographic area on the basis of high school grades, preliminary SAT scores, and teacher recommendations. The thirty or so students chosen all had excellent credentials. Students were rising seniors or juniors in high school, and the program lasted six weeks with the students housed in dormitories on campus.
Current and Future Clinical Applications for Optical Imaging of Cancer: From Intraoperative Surgical Guidance to Cancer Screening

Optical imaging is an inexpensive, fast, and sensitive imaging approach for the noninvasive detection of human cancers in locations that are accessible by an optical imaging device. Light is used to probe cellular and molecular function in the context of cancer in the living body. Recent advances in the development of optical instrumentation make it possible to detect optical signals produced at a tissue depth of several centimeters. The optical signals can be endogenous contrasts that capture the heterogeneity and biological status of different tissues, including tumors, or extrinsic optical contrasts that selectively accumulate in tumors to be imaged after local or systemic delivery. The use of optical imaging is now being applied in the clinic and operating room for the localization and resection of malignant tumors in addition to screening for cancer.
ON DYNAMIC THEORIES OF FIBER-REINFORCED COMPOSITES.

Abstract : The well-known effective modulus theory of fiber-reinforced composites is generally suitable for static analysis. For dynamic problems, however, its applicability is less certain. The dispersion of free harmonic waves, for example, to be expected in an extended composite, cannot be accounted for by the effective modulus theory. In this paper a theory is proposed for the dynamic analysis of layered and fiber-reinforced composites, in which the identity of reinforcing elements is preserved. The elastic and geometric properties of the sheets or fibers are combined into effective stiffnesses. With the aid of certain supplementary kinematical assumptions describing the deformations of the reinforcing elements a single set of field equations is derived. The equations of motion presented are analogous to those of the theory of linear elasticity with microstructure. To test the viability of the proposed theory the dispersion characteristics of free harmonic waves propagating in the direction of the reinforcing elements are analyzed. For a periodic structure consisting of alternating layers the 'exact' dispersion curves for the lowest mode were obtained by solving the appropriate elasticity problem. The approximate and exact dispersion curves are compared. (Author)
Voice-controlled trarinable manipulators with visual feedback

A hierarchically intelligent control algorithm, accepting discrete voice input commands and feed-back visual information from a television camera has been developed to control the MIT Scheinman electric arm in real time. The project developed to assist immobilized people, confined in limited environments, employs a task-oriented hierarchically intelligent control approach. The motion of the arm, though considered to be composed of motion of the wrist and orientation of the hand, results from the simultaneous execution of these two distinct motions. A task-directed linguistic command or voice command is recognized, interpreted, and decoded into sequences of subtasks. The first sub-task corresponds to the motion of the wrist which is controlled by the suboptimal feedback controller. The remaining four subtasks are further broken down into combinations of six primitive movements which govern the position/orientation of the hand. The objective of the visual recognition algorithm is to identify objects and their locations surrounding the arm from its environmental library. The library is then updated to initiate the arm to complete its execution of task. The real-time implementation of the algorithm on the MIT arm of the Advanced Automation Research Laboratory (AARL) of Purdue University has demonstrated the feasibility of the algorithm and its advantages in terms of time execution and efficiency of implementation.
Evaluation of normal yellow dent corn and high available phosphorus corn in combination with reduced dietary phosphorus and phytase supplementation for broilers grown to market weights in litter pens.

Abstract A study was conducted to determine the extent fecal P levels could be reduced while maintaining performance. Various strategies were employed including the use of a high available phosphorus hybrid of corn (HAPC), supplementation with phytase enzyme, and reduced dietary P levels. The use of HAPC resulted in a 50% reduction in phytate-bound dietary P as compared with a normal yellow dent corn (YDC) diet. Dietary nonphytate P was maintained at either NRC (1994) recommendations for appropriate age periods or reduced by 0.075 or 0.15%. Portions of the diets were supplemented with 1,000 units of phytase/kg. Male chicks of a commercial strain were grown to 56 d on the test diets. Broilers fed diets with HAPC had BW, feed conversion, livability, and tibia ash that were equal to or superior to those fed diets with YDC with considerably reduced fecal P content at any dietary level of nonphytate P. Phytase supplementation enabled birds to maintain live performance at lower levels of nonphytate P, further reducing the fecal P output. One of the greatest contributions of phytase was a reduction in mortality at the lower levels of nonphytate P. Dietary P levels could be reduced by 0.075% under NRC (1994) recommendations without adversely affecting live performance; a reduction of 0.15% in conjunction with phytase supplementation maintained BW, feed conversion, and livability but reduced tibia ash. The extent to which dietary P levels can be reduced over the entire feeding program is subject to further research.
USE OF THE IN VITRO BACTERICIDAL ASSAY TO MEASURE FUNCTIONAL OPSONINS IN CONTROL (C) AND WISKOTT-ALDRICH PATIENTS (WA)

USE OF THE IN VITRO BACTERICIDAL ASSAY TO MEASURE FUNCTIONAL OPSONINS IN CONTROL (C) AND WISKOTT-ALDRICH PATIENTS (WA)
An efficient single-mode Nd3+ fiber laser prepared by the sol-gel method

High quality Nd-doped single-mode fibers have been prepared by using a sol-gel process. The longest fluorescence lifetime measured was 520 μs in an Al: SiO2 glass fiber containing 0.47 wt.% neodymium oxide. An efficient neodymium fiber laser with a slope above threshold of 42% was successfully demonstrated with the sol-gel prepared Nd-doped single-mode fibers as a fiber laser oscillator.
NO1: An HLA-DQw1-associated determinant present on loss mutants not expressing DQw1☆

Abstract We have used two monoclonal antibodies, FA and Tu39, and cloned cytotoxic T lymphocytes to study the immunogenetic control of an HLA-D region-encoded determinant(s) recognized by the Tc other than class I or DR or DQ. The Tc recognize a determinant associated with one (the A2) haplotype of LCL721 and are lytic to mutants of LCL 721 that have lost expression of all class I as well as the serologically defined DR and DQw specificities associated with the A2 haplotype. Those cloned Tc blocked by FA recognized a determinant associated with, and presumably identical to, DPw2, the specificity encoded by the sensitizing (A2-B51) haplotype; these data provide the first evidence that FA recognizes the protein dimer presumably expressing the DPw determinant. Those Tc blocked by Tu39 recognized a determinant, referred to as NO1, that is not associated in the population with DPw2, but is found on some, but not all, DQw1-positive cells. We propose three possible explanations for these results. (i) There may be a class II product other than DP or those expressing the DR or DQ serologically defined specificities carrying NO1; such a product could be either as yet underscribed (E. Long has obtained information for an expressed and as yet undefined class II β gene, personal communication) or a second expressed dimer of the DQ or DP families. (We assume that no DR genes of the A2 haplotype are expressed in these mutants. (ii) NO1 and DPw2 may be on the same molecule; to account for the lack of association of NO1 and DPw2 in the population, one might propose a mechanism such as gene conversion leading to expression of NO1. (iii) The fact that NO1, in our small panel, is found only on a subset of DQw1 + cells, suggests that NO1 may be a determinant on a molecule encoded by genes in linkage disequilibrium with DQ or may involve a dimer that consists of both a DQ chain and some other chain. NO1 is probably on a different molecule from that carrying DQw1, since two separately derived loss mutants that no longer express DQw1 still express NO1.
Solution of the mild-slope wave problem by iteration

Iterative solution procedures for solving the complete mild-slope wave (combined refractiondiffraction) equation are developed. Existing models for investigating wave refraction-diffraction in coastal areas have one of two main problems: (i) Some of the physics is lost as they resort to approximate solutions (e.g. parabolic approximations). Thus they are inappropriate in many situations. (ii) If all of the physics is to be incorporated, the problem defies computer solution except for extremely small domains (approximately 10 wavelengths), chiefly because the matrix equation associated with numerical discretization of the complete problem does not normally lend itself to solution by iteration. This paper describes the construction of iterative models that overcome both problems. First, a modified equation with an identical solution but which lends itself to iterative procedures is formulated, and the conjugate gradient method is used. A second, more rapidly converging algorithm is obtained by preconditioning. It is shown that the algorithms can be conveniently implemented on regions much larger than those handled by conventional models, without compromising the physics of the equation. Further, they can be efficiently run in either the linear or nonlinear mode. Comparisons of model results with laboratory data and other numerical and analytical solutions are found to be excellent for several cases. The procedures thus enable the engineer to expand the scope of the mild-slope equation. As an example, an experiment is performed to demonstrate the sensitivity of the wavefield to the location of a breakwater in a region with complex bathymetry.
Between Games and Failure: A Micro-Ethnographic Study of Navajo Students and Testing.

Students and teachers live together in classrooms where testing is a frequent and often traumatic occurrence. Studies (Coleman, 1966; Levine, 1976; Rohwer, 1971) show that minority students consistently score lower on tests than students from the dominant socio-cultural group in American society. This study was an ethnographic investigation of tests and testtaking among Navajo students in a Bureau of Indian Affairs (BIA) day school. Its purpose was to examine the perceptions and attitudes of Navajo students toward test-taking. The method most frequently used to examine the depressed achievement of minority students has been a psychometric or statistical analysis of tests and test scores (Coleman, 1966). Mercer (1972) goes one step further in a psychometric study which attempts to rectify the disparity of test scores by developing a socio-cultural index, creating pluralistic norms, which are then interpreted along with standardized norms of the test as published in the test manuals. Another method has been to examine the cultural differences of the students, relying on anthropological data to support differences of learning styles, attitudes, and values (Cohen, 1969; Gay and Abrahams, 1973; Harris, 1976; Hernandez, 1973; Maehr, 1974; Piersel, 1977; Rohwer, 1971). Within this method attempts have been made to develop "culture-free" tests, to adapt present tests for cross-cultural applications, and to develop distinct tests for particular socio-cultural groups. Both of these approaches have been valuable, but, ultimately, they do not address the basic processes involved in the actual event of testing. How does the idea and/or importance of a test develop among students? Research which starts with the test scores themselves obscures or neglects the processes the student is involved in up until he or she actually puts
Silicon and Silicon-Germanium Raman Laser

We report the demonstration of lasing and amplification using the Raman effect in Si/SiGe waveguides. Electronic switching of the laser and tailoring of Raman spectrum via phonon engineering in SiGe alloys are also presented.
Similar reductions in the risk of human colon cancer by selective and nonselective cyclooxygenase-2 (COX-2) inhibitors

Background Epidemiologic and laboratory investigations suggest that aspirin and other nonsteroidal anti-inflammatory drugs (NSAIDs) have chemopreventive effects against colon cancer perhaps due at least in part to their activity against cyclooxygenase-2 (COX-2), the rate-limiting enzyme of the prostaglandin cascade.
The effects of low and high levels of vigilance on subsequent visual exploratory behavior in humans

Theoretical accounts of visual exploration have emphasized two classes of variables as important determinants of visual investigations: (1) the state of the organism and (2) the characteristics of the stimulus. While the latter class of variables has been investigated extensively, there is little, if any, literature concerning effects of organismic states on visual exploration. The present two experiments manipulated organismic states by having Ss perform repetitive vigilance tasks. The first study indicated that Ss who engaged in a highly repetitive vigilance task viewed complexity stimuli nearly twice as long as Ss engaged in a task requiring very little vigilance. The second study discounted the possibility that this effect was due to “time-off” behavior. The two studies open a new avenue for research in visual exploration.
Electrocardiographic diagnosis of myocardial infarction in the presence of complete left bundle branch block

Whether myocardial infarction (MI) can be diagnosed electrocardiographically in the presence of left bundle branch block (LBBB) is controversial. Our study sought to test the reliability of ECG criteria for diagnosing MI in patients with LBBB. Among 985 patients presenting within 18 hours of the onset of ischemic chest pain, 35 had complete LBBB. Acute MI was identified by serial MB-creatine kinase (CK) elevations and prior MI was determined by previously documented ECG and/or enzyme changes. Among those with LBBB, 24 patients had acute and/or prior MI, while 11 had neither. Eleven ECG criteria previously proposed for detecting MI in the presence of LBBB were evaluated. In patients presenting with ischemic chest pain and complete LBBB, presence of any one of the following ECG criteria was highly specific (90% to 100%) and predictive (85% to 100%) for acute or prior MI: Q waves in at least two of leads I, aVL, V5, or V6; R wave regression from V1 to V4; notching of the upstroke of the S wave in at least two of leads V3, V4, or V5, and primary ST-T wave changes in two or more adjacent leads.
A comparison between peritoneal sheathing of the ureters (Ohkawa technique) and retroperitoneal pelvic suction drainage in the prevention of ureteral damage during radical abdominal hysterectomy

Sixty patients had a radical abdominal hysterectomy with or without a bilateral salpingo-oophorectomy. The Ohkawa procedure was utilized in 26 (43.3%) of the patients and retroperitoneal ureteral placement with suction drainage in 34 (56.7%) of the patients. These two operative procedures were evaluated for complications such as fistula, obstruction, and hydronephrosis by comparing preoperative and postoperative intravenous pyelograms. Five of the 60 patients (8.3%) had surgical complications within one postoperative month. A ureteral obstruction occurred in two patients, and a uretrovaginal fistula occurred in two patients. Hydronephrosis was found in both sets of patients. All of these complications occurred in an additional two patients, both of whom had an Ohkawa procedure. The study led us to conclude that retroperitoneal ureteral placement is not only quicker to perform but also leads to fewer complications than the Ohkawa technique.
Excess protein O-GlcNAcylation and the progression of diabetic cardiomyopathy

We examined the role that enzymatic protein O-GlcNAcylation plays in the development of diabetic cardiomyopathy in a mouse model of Type 2 diabetes mellitus (DM2). Mice injected with low-dose streptozotocin and fed a high-fat diet developed mild hyperglycemia and obesity consistent with DM2. Studies were performed from 1 to 6 mo after initiating the DM2 protocol. After 1 mo, DM2 mice showed increased body weight, impaired fasting blood glucose, and hyperinsulinemia. Echocardiographic evaluation revealed left ventricular diastolic dysfunction by 2 mo and O-GlcNAcylation of several cardiac proteins and of nuclear transcription factor Sp1. By 4 mo, systolic dysfunction was observed and sarcoplasmic reticulum Ca2+ ATPase expression decreased by 50%. Fibrosis was not observed at any timepoint in DM2 mice. Levels of the rate-limiting enzyme of the hexosamine biosynthetic pathway, glutamine:fructose-6-phosphate amidotransferase (GFAT) were increased as early as 2 mo. Fatty acids, which are elevated in DM2 mice, can possibly be linked to excessive protein O-GlcNAcylation levels, as cultured cardiac myocytes in normal glucose treated with oleic acid showed increased O-GlcNAcylation and GFAT levels. These data indicate that the early onset of diastolic dysfunction followed by the loss of systolic function, in the absence of cardiac hypertrophy or fibrosis, is associated with increased cardiac protein O-GlcNAcylation and increased O-GlcNAcylation levels of key calcium-handling proteins. A link between excessive protein O-GlcNAcylation and cardiac dysfunction is further supported by results showing that reducing O-GlcNAcylation by O-GlcNAcase overexpression improved cardiac function in the diabetic mouse. In addition, fatty acids play a role in stimulating excess O-GlcNAcylation. The nature and time course of changes observed in cardiac function suggest that protein O-GlcNAcylation plays a mechanistic role in the triggering of diabetic cardiomyopathy in DM2.
A spheroplast rate assay for determination of cell wall integrity in yeast

The rate of formation of spheroplasts of yeast can be used as an assay to study the structural integrity of cell walls. Lysis can be measured spectrophotometrically in hypotonic solution in the presence of Zymolyase, a mixture of cell wall-digesting enzymes. The optical density of the cell suspension decreases as the cells lyse. We optimized this assay with respect to enzyme concentration, temperature, pH, and growth conditions for several strains of Saccharomyces cerevisiae. The level of variability (standard deviation) was 1–5% between trials where the replications were performed on the same culture using enzyme prepared from the same lot, and 5–15% for different cultures of the same strain. This assay can quantitate differences in cell wall structure (1) between exponentially growing and stationary phase cells, (2) among different S. cerevisiae strains, (3) between S. cerevisiae and Candida albicans, (4) between parental and mutated lines, and (5) between drug- or chemically-treated cells and controls. © 1998 John Wiley & Sons, Ltd.
Aging properties of Kodak type 101 emulsions.

Aging tests for several batches of Kodak type 101 emulsion show that storage conditions significantly influence how well the film will maintain its sensitometric properties, with sensitivity and density increasing to a maximum during this period. Any further aging may result in higher fog levels and sensitivity loss. It is noted that storage in an environment free of photographically active compounds allows film property optimization, and that film batches with different sensitivities age differently. Emulsions with maximum 1700-A sensitivity are 2.5 times faster than those at the low end of the sensitivity scale. These sensitive emulsions exhibit significantly accelerated changes in aging properties. Their use in space applications requires careful consideration of time and temperature profiles, encouraging the use of less sensitive emulsions when the controllability of these factors is limited.
Mixed function oxidase activities in lactating rats and their offspring following dietary exposure to polybrominated biphenyls

Abstract Exposure of pregnant rats to diet containing 50 ppm polybrominated biphenyls (PBBs) from day 8 of gestation to day 15 postpartum caused significant increases in hepatic and extrahepatic microsomal mixed function oxidase activity. Hepatic arylhydrocarbon hydroxylase (AHH), epoxide hydratase (EH), hexobarbital hydroxylase (hex-OH), and the 2- and 4-hydroxylation of biphenyl (2-OHBP, 4-OHBP) were increased 10, 3, 3, 23, and 6-fold respectively in animals fed diet containing PBBs. The hex-OH, 2-OHBP, and 4-OHBP activities were not detectable in the S9 fraction from maternal mammary glands of control or PBB-fed rats; however, exposure to PBBs increased mammary AHH 2.5-fold and decreased EH activity 45%. Renal AHH activity was increased 7-fold but renal EH activity was unaltered by feeding PBBs. Pups from control and PBB-exposed mothers were crossfostered at birth to give offspring which received PBB exposure prenatally, postnatally (via mothers milk), or both pre- and postnatally. Each type of exposure produced increases in hepatic AHH and EH activities over those found in pups born to and raised by mothers which received no PBBs. The results demonstrate that PBBs induce hepatic and extrahepatic mixed function oxidase activity in nursing rats and that the extrahepatic effects of the mixture are different from the hepatic effects. Furthermore, PBBs were effective stimulators of hepatic enzymes in 15-day-old rats when the neonates were exposed transplacentally and/or via the mothers' milk. The results suggest potential toxic interaction between PBBs and other agents which are of importance to both mother and young.
Artifactual averaged 'twitch tension' waveforms resulting from synchronized activity: recording from feline diaphragmatic motor units.

Averaging techniques have been used to measure contractile properties of spontaneously active motor units (MUs). This study examined the potential for artifactual results due to synchronization between the triggering, single-MU action potentials, and activity of other MUs within the muscle. A muscle strip was formed in situ from feline diaphragm. Single MUs were recorded from the strip and from the contralateral diaphragm. The diaphragm including the muscle strip continue to contract rhythmically in this preparation and a high-gain, AC-coupled recording of force was averaged using MUs recorded in either hemidiaphragm to trigger the averager. Twitch-tension waveforms occurred in 42 of 49 cases triggering from spikes of MUs contained within the strip and in 13 of 19 averages triggered from contralateral MUs. The waveforms generated using contralateral MUs as triggers could only arise from synchronization with MUs contained within the diaphragmatic strip. Although twitch waveforms that were generated from external and internal triggers could appear similar qualitatively, contraction times were significantly (P < 0.05) longer for averages using contralateral MUs. This study demonstrates that synchronization of triggering events is a major source for error in determining mechanical properties of MUs.
Geochemistry of Flooded Underground Mine Workings Influenced by Bacterial Sulfate Reduction

Unlike the majority of the water in the flooded mine complex of Butte Montana, which includes the highly acidic Berkeley pit lake, groundwater in the flooded West Camp underground mine workings has a circum-neutral pH and contains at least 8 μM aqueous sulfide. This article examines the geochemistry and stable isotope composition of this unusual H2S-rich mine water, and also discusses problems related to the colorimetric analysis of sulfide in waters that contain FeS(aq) cluster compounds. The West Camp mine pool is maintained at a constant elevation by continuous pumping, with discharge water that contains elevated Mn (90 μM), Fe (16 μM), and As (1.3 μM) but otherwise low metal concentrations. Dissolved inorganic carbon in the mine water is in chemical and isotopic equilibrium with rhodochrosite in the mineralized veins. The mine water is under-saturated with mackinawite and amorphous FeS, but is supersaturated with Cu- and Zn-sulfides. However, voltammetry studies show that much of the dissolved sulfide and ferrous iron are present as FeS(aq) cluster molecules: as a result, the free $$ {\hbox{H}}_{\hbox{2}} {\hbox{S}}\,{\hbox{ + }}\,{\hbox{HS}}^{\hbox{ - }} $$ concentration of the West Camp water is poorly constrained. Concentrations of dissolved sulfide determined by colorimetry were lower than gravimetric assays obtained by AgNO3 addition, implying that the FeS(aq) clusters are not completely extracted by the Methylene Blue reagent. In contrast, the clusters are quantitatively extracted as Ag2S after addition of AgNO3. Isotopic analysis of co-existing aqueous sulfide and sulfate confirms that the sulfide was produced by sulfate-reducing bacteria (SRB). The H2S-rich mine water is not confined to the immediate vicinity of the extraction well, but is also present in flooded mine shafts up to 3 km away, and in samples bailed from mine shafts at depths up to 300 m below static water level. This illustrates that SRB are well established throughout the southwestern portion of the extensive (>15 km3) Butte flooded mine complex.
Delayed Onset Postvaccinal Mucosal Disease as a Result of Genetic Recombination between Genotype 1 and Genotype 2 BVDV

Bovine viral diarrhea viruses (BVDV) are segregated into two genotypes, BVDV 1 and BVDV 2. Viruses within both genotypes may exist as one of two biotypes, cytopathic or noncytopathic. A highly fatal form of BVDV termed mucosal disease (MD) occurs when an animal persistently infected with noncytopathic BVDV becomes superinfected with cytopathic BVDV. In this study, we characterized a noncytopathic (BVDV2-125nc)/cytopathic (BVDV2-125c) viral pair isolated from an animal that died of MD 3 months after vaccination with modified-live BVDV1-NADL. In comparison to BVDV2-125nc, BVDV2-125c contained a 366-nucleotide insertion. The insertion was in the correct reading frame for the large open reading frame of the BVDV genome and occurred in the portion of the genome that codes for the p125 viral polypeptide. There was a 99% identity between the inserted sequences found in BVDV2-125c and sequences from the vaccine virus BVDV1-NADL. These data suggest that MD was induced after a recombination between noncytopathic BVD2-125nc and cytopathic vaccine virus BVDV1-NADL created the cytopathic virus BVDV2-125c.
Turbo FISH: A Method for Rapid Single Molecule RNA FISH

Advances in RNA fluorescence in situ hybridization (RNA FISH) have allowed practitioners to detect individual RNA molecules in single cells via fluorescence microscopy, enabling highly accurate and sensitive quantification of gene expression. However, current methods typically employ hybridization times on the order of 2–16 hours, limiting its potential in applications like rapid diagnostics. We present here a set of conditions for RNA FISH (dubbed Turbo RNA FISH) that allow us to make accurate measurements with no more than 5 minutes of hybridization time and 3 minutes of washing, and show that hybridization times can go as low as 30 seconds while still producing quantifiable images. We further show that rapid hybridization is compatible with our recently developed iceFISH and SNP FISH variants of RNA FISH that enable chromosome and single base discrimination, respectively. Our method is simple and cost effective, and has the potential to dramatically increase the throughput and realm of applicability of RNA FISH.
Kappa-bungarotoxin: a probe for the neuronal nicotinic acetylcholine receptor

Abstract Snake venom α-neurotoxins are excellent ligands for identifying and characterizing nicotinic acetylcholine receptors from skeletal muscle and muscle derived tissues. An α-neurotoxin referred to as Kappa-bungarotoxin (KBgT) has recently been isolated. KBgT is among a class of α-neurotoxins which are unusual in that they block nicotinic transmission in a number of neuronal preparations where most other α-neurotoxins are ineffective. KBgT appears to be a specific probe for the neuronal nicotinic receptor.
Alternative Things Considered: A Political Economic Analysis of Labour Processes and Relations at a Honolulu Alternative Newspaper:

The `alternative' media realm, formed as a result of the social and civil rights movements of the 1960s and recommended by some critical media analyses, aims to provide a counterbalance to more mainstream media. Drawing on the work of Herman and Chomsky, and Giddens, this article maps out the parameters of one alternative newspaper organization located in Honolulu, Hawai'i from the perspective of those who work there. Using a political-economic lens, the article focuses on the enabling and constraining conditions of employment at the Honolulu Weekly and, in turn, helps us to understand more fully the dilemma of `alternative' news work, news organizations, their institutional arrangements and dominant societal arrangements.
A general MPCC model and its solution algorithm for continuous network design problem

This paper formulates the continuous network design problem as a mathematical program with complementarity constraints (MPCC), with the upper level a nonlinear programming problem and the lower level a nonlinear complementarity problem. Unlike in most previous studies, the proposed framework is more general, in which both symmetric and asymmetric user equilibria can be captured. By applying the complementarity slackness condition of the lower-level problem, the original bilevel formulation can be converted into a single-level and smooth nonlinear programming problem. In order to solve the problem, a relaxation scheme is applied by progressively restricting the complementarity condition, which has been proven to be a rigorous approach under certain conditions. The model and solution algorithm are tested for well-known network design problems and promising results are shown.
ELECTRONIC SPECTRAL EFFECTS ON CHIRAL SURFACE SECOND HARMONIC GENERATION

Abstract A molecular level interpretation of the chiroptical effects observed in surface second harmonic generation from a chiral surface is presented. A Pariser, Parr and Pople molecular orbital treatment is used to calculate the hyperpolarizability of R-2,2'-dihydroxy-1,1'-binaphthyl (R-BN). The chiroptical spectra from monolayers of R-BN are calculated using various assumed molecular orientational distributions, and the model spectra compare favorably with experimental data.
Is there a constitutional right to preconception sex selection

(2001). Is There a Constitutional Right to Preconception Sex Selection? The American Journal of Bioethics: Vol. 1, No. 1, pp. 27-28.
307 Disturbed Cardiac Functional Parameters and Blood Flow Parameters of Peripheral Arteries in Premature Sga Neonates

Top of pageAbstract Problem: Small for gestational age preterm neonates (SGA) are at higher risk for early postnatal morbidity and cardiovascular and metabolic diseases in later childhood. The aim of the prospective study was to determine the cardiac adaptation and the organ blood flow in growth retarded neonates after intrauterine hemodynamic disturbances in comparison to appropriate for gestational age preterm infants (AGA). Patients and methods: 25 AGA neonates (29.1 ± 1.4 wks, 1420 ± 243 g) and 25 small for gestational age neonates (30.1 ± 1.2 wks, 985 ± 167 g) were examined during the first five days. By Doppler sonographic measurements the cardiac left ventricular systolic time intervals, peak systolic velocities, end diastolic velocities and pulsatility indices of anterior cerebral artery (ACA), superior mesenteric artery (SMA) and renal artery (RA) were investigated. Results: Significantly increased left ventricular pre ejection period was observed in SGA neonates. Systolic peak velocities and end diastolic velocities of ACA, SMA and RA were significantly decreased in SGA neonates in relationship to AGA neonates. The pulsatility indices were significantly increased in SGA neonates during the first five days. Conclusions: Disturbed left ventricular time intervals were observed as a sign of myocardial dysfunction in SGA neonates. In relationship to the diminished myocardial contractility there were demonstrated pathologically diminished blood flow parameters of peripheral vessels and an increased pulsatility caused by a vasoconstriction in the regional vascular bed. For that reason it seems possible, that the disturbed intrauterine perfusion persists into the postnatal life and could cause later cardiac and metabolic problems.
A Diagnostic for the Condition of Dielectrics

It is pointed out that the determination of a key parameter that enters into a recent, widely applicable theory of the dynamics of low frequency phenomena, may be a sensitive means to monitor the status of a dielectric. It is shown how, in principle, measurements of dielectric susceptibility and/or thermal voltage noise provide the means to determine that parameter.
Guyed tower optimization

Abstract A unique procedure for the optimum design of a guyed tower structure is presented. The method depends on a carefully established design hierarchy which is based on the observed independence of the design variables in certain portions of the design space. Powell Search and Branch-and-Bound sub-optimization routines are used to generate locally optimum designs in terms of cable area, initial cable tension, mast area and anchor to tie locations. A design example is presented and computer program capabilities are discussed.
Reincarnation of the One Room Schoolhouse - The American Middle School

(1975). Reincarnation of the One Room Schoolhouse - The American Middle School. The Clearing House: A Journal of Educational Strategies, Issues and Ideas: Vol. 49, No. 3, pp. 103-105.
Cell interaction with a synthetic polynucleotide and interferon production in vitro.

Abstract The first step in interferon production by double-stranded polyribocytidylate: polyriboinosinate (poly C:I) is the binding of poly C:I to the cell surface. It can be demonstrated either at 4° or at 37°. Using radiolabeled poly C:I, cell binding of poly C:I was shown to be greatly enhanced by DEAE-dextran. A second, temperature-dependent step occurs rapidly after cell binding of poly C:I and is followed by cellular resistance to virus infection and interferon production. Study of this temperature-dependent step showed that the bulk of cell-associated poly C:I persists at the cell surface and that very little poly C:I is taken into cells during this time. Autoradiography of human fibroblasts incubated for various intervals with tritiated poly C:I at 37° showed that poly C:I is degraded in cells and that the fragments are utilized for cellular RNA synthesis. Such utilization could be blocked by treatment of cells with actinomycin D and cytidine while interferon production was not decreased. Study of the interaction of poly C:I with L cells indicated that these cells take up similar amounts of poly C:I as human fibroblasts under the same conditions but do not produce interferon in the absence of DEAE-dextran. Our findings suggest that the amount of cell-associated poly C:I required for initiation of interferon production is not the same in different cell systems and further suggest that much of the cellular uptake of poly C:I is not essential for interferon production.
Characteristics of successful directors of for‐profit child care centers

The need for quality child care is a national concern of increasing interest to parents, child care providers, employers, and policy‐makers in the United States. One of the newest entries in child care options available for consumers is for‐profit daycare chains. As for‐profit chains increase in both number and size, they will receive increased research attention. Few studies have examined for‐profit centers in general or the background characteristics of their directors specifically. The purpose of this research was to develop a profile of directors of for‐profit child care centers and to investigate whether certain background variables, such as level of education, differentiated “successful” from “unsuccessful” directors. Data were collected on 362 child care directors employed during a three‐year period with a nation‐wide daycare chain in the United States.
The US effort to dispose of high-level radioactive waste

This paper reviews the history of the US effort to dispose of high-level radioactive waste created by operating nuclear fission reactors for military and commercial purposes. The history is considered here in three parts: the period beginning in 1957 and ending with passage of the Nuclear Waste Policy Act in 1982; implementation of that Act over the period 1982 to 2005; and recent plans to promote a nuclear power "renaissance", including the initiation of the Global Nuclear Energy Partnership in 2006. To date, disposal has not been accomplished, and many observers doubt that disposal will occur during the next several decades. The history of the disposal effort features a series of decision-action cycles in which objectives were formulated, decisions were taken, actions were implemented, and outcomes occurred. The decision-action process is examined here with attention to the roles and objectives of major stakeholders, the relation of those objectives to governmental decisions, and the extent to which the...