cssi/SciSciGPT-SciSciNet huggingface dataset:
Effects of postnatal trimethyltin or triethyltin treatment on CNS catecholamine, GABA, and acetylcholine systems in the rat.

The effects on brain neurochemistry of two neurotoxic tin compounds, trimethyltin (TMT) hydroxide and triethyltin (TET) sulfate, were examined. Long-Evans rats were treated with TMT hydroxide (1 mg/kg, i.p.) on alternate days from day 2 to 29 of life. These treatments caused a weight deficit of 10-20% by the time the animals were killed on day 55 by head-focused microwave irradiation. These TMT treatments are known to cause severe neuronal loss in the hippocampus and lesser damage in other brain regions. Accordingly, the concentration of gamma-aminobutyric acid (GABA) was decreased in the hippocampus; however, acetylcholine and choline concentrations were unaffected. These data suggest that TMT-induced effects on GABA systems are greater than that due simply to generalized neuronal loss. The TMT treatments also caused a significant decrease in dopamine concentrations in the striatum, but did not alter the concentrations of dihydroxyphenylacetic acid or homovanillic acid, the acidic metabolites of dopamine. Conversely, concentrations of dopamine and norepinephrine in the brain stem and norepinephrine in the cerebellum were not altered. Despite reports in the literature of TMT-induced neuronal damage in areas of the cortex, no effects on GABA, acetylcholine, or choline levels were found in the cortical areas examined, or in the hypothalamus. TET sulfate (0.3 mg/kg/day) was administered for 6 consecutive days of every week during days 2-29 of life. This dose is lower than that needed to cause intramyelin edema, yet it does result in long-term behavioral changes. Despite this, no changes in the concentration of any of the measured neurotransmitters or their metabolites were detected. In concert, these data demonstrate that neurochemical methods should not be used as neurological "screens," but rather to define specific mechanisms suggested by detailed behavior, pharmacological, and/or physiological studies.
ON THE REGULATION OF THE MORPHOGENESIS OF BACTERIOPHAGE T4.

Two steps in the morphogenesis of bacteriophage T4 were studied; the formation of the “early” proteins and of phage structural elements. The synthesis of the “late” phage proteins was prevented if the “early” proteins were defective (containing 7-azatryptophan or p -fluorophenylalanine). Inhibition of protein synthesis by 5-methyltryptophan similarly affects the normal morphogenesis of phage. These results suggest that a “clock” or timing mechanism is inhibited in the absence of normal “early” proteins. In contrast, 5-fluorodeoxyuridine which inhibits the synthesis of normal phage permits the appearance of phage structural proteins.
Changes in atmospheric carbon-14 attributed to a variable sun.

The (14)C production rate in the upper atmosphere changes with time because the galactic cosmic-ray flux responsible for (14)C production is modulated by the changes in solar wind magnetic properties. The resulting changes in the atmospheric (14)C level are recorded in tree rings and are used to calculate past (14)C production rates from a carbon reservoir model that describes terrestrial carbon exchange between the atmosphere, ocean, and biosphere. These past (14)C production rate changes are compared with (14)C production rates determined from 20th-century neutron flux measurements, and a theory relating (14)C production and solar variability, as given by geomagnetic Aa indices and sunspot numbers, is developed. This theory takes into account long-term solar changes that were previously neglected. The 860-year (14)C record indicates three episodes when sunspots apparently were absent: A.D. 1654 to 1714 (Maunder minimum), 1416 to 1534 (Sporer minimum), and 1282 to 1342 (Wolf minimum). A less precisely defined minimum occurred near A.D. 1040. The part of this record after A.D. 1645 correlates well with the basic features of the historical record of sunspot numbers. The magnitude of the calculated (14)C production rates points to a further increase in cosmic-ray flux when sunspots are absent. This flux was greatest during the Sporer minimum. A record of approximate sunspot numbers and Aa indices for the current millennium is also presented.
Observations of school library impact at two rural Ugandan schools

Purpose – The purpose of this research is to explore connections between the presence of a library at two schools in rural Uganda and certain student academic engagement indicators, such as scholastic performance, reading habits, study habits, and library use patterns. The study is not intended to demonstrate strong correlations between these items, rather, it is a limited exploration of certain questions meant to inform further enquiry in the area. Five specific questions guided the research: Do students with a school library read more? Do students make good use of the library? Do students recognize the importance of having the library? Do students use the library materials for other than class‐related work? Are there any noticeable differences between the grades of students with the library at their school, and those without?Design/methodology/approach – Researchers gathered both quantitative and qualitative data from two different schools in the Masaka District, one school with a library, the Kitengesa...
Health and Safety Practices in the Nanomaterials Workplace: Results from an International Survey

This article reports the findings of an international survey of nanomaterials firms and laboratories regarding their environmental health and safety (EHS) programs, engineering controls, personal protective equipment (PPE), exposure monitoring, waste disposal, product stewardship, and risk beliefs. While many participants reported not believing that nanomaterials pose special risks, nanospecific EHS programs were still widely reported. Most nanospecific EHS programs appeared to build from general EHS programs but included nanospecific workplace engineering controls and recommendations for clothing, gloves, eye protection, and respirators. Organizations with nanospecific EHS programs also reported providing product (safe use) guidance to consumers. However, workplace monitoring and nanospecific waste disposal were uneven and were only associated with the subset of organizations believing in special risks. A majority of organizations expressed a need for more toxicological information and EHS guidance. Overall, this study suggests that nanomaterials firms and laboratories are already attentive to nanospecific EHS and product stewardship issues. However, improved risk communication is needed to further the implementation of related programs. Organizations that are wholly inattentive to EHS would likely engage in nanospecific EHS upon implementing a staffed, general EHS program.
Involvement of lipid peroxidation-derived aldehyde-protein adducts in autoimmunity mediated by trichloroethene.

Lipid peroxidation, a major contributor to cellular damage, is also implicated in the pathogenesis of autoimmune diseases (AD). The focus of this study was to elucidate the role of lipid peroxidation-derived aldehydes in autoimmunity induced and/or exacerbated by chemical exposure. Previous studies showed that trichloroethene (TCE) is capable of inducing/accelerating autoimmunity. To test whether TCE-induced lipid peroxidation might be involved in the induction/exacerbation of autoimmune responses, groups of autoimmune-prone female MRL +/+ mice were treated with TCE (10 mmol/kg, i.p., every 4th day) for 6 or 12 wk. Significant increases of the formation of malondialdehyde (MDA)- and 4-hydroxynonenal (HNE)–protein adducts were found in the livers of TCE-treated mice at both 6 and 12 wk, but the response was greater at 12 wk. Further characterization of these adducts in liver microsomes showed increased formation of MDA–protein adducts with molecular masses of 86, 65, 56, 44, and 32 kD, and of HNE–protein a...
Characterization of a TM-4 type tropomyosin that is essential for myofibrillogenesis and contractile activity in embryonic hearts of the Mexican axolotl

A striated muscle isoform of a Tropomyosin (TM-4) gene was characterized and found to be necessary for contractile function in embryonic heart. The full-length clone of this isoform was isolated from the Mexican axolotl (Ambystoma mexicanum) and named Axolotl Tropomyosin Cardiac-3 (ATmC-3). The gene encoded a cardiac-specific tropomyosin protein with 284 amino acid residues that demonstrated high homology to the Xenopus cardiac TM-4 type tropomyosin. Northern blot analysis indicates a transcript of ∼1.25 kb in size. RT-PCR and in situ hybridization demonstrated that this isoform is predominantly in cardiac tissue. Our laboratory uses an animal model that carries a cardiac lethal mutation (gene c), this mutation results in a greatly diminished level of tropomyosin protein in the ventricle. Transfection of ATmC-3 DNA into mutant hearts increased tropomyosin levels and promoted myofibrillogenesis. ATmC-3 expression was blocked in normal hearts by transfection of exon-specific anti-sense oligonucleotide (AS-ODN). RT-PCR confirmed lower transcript expression of ATmC-3 and in vitro analysis confirmed the specificity of the ATmC-3 exon 2 anti-sense oligonucleotide. These AS-ODN treated hearts also had a disruption of myofibril organization and disruption of synchronous contractions. These results demonstrated that a striated muscle isoform of the TM-4 gene was expressed embryonically and was necessary for normal structure and function of the ventricle. J. Cell. Biochem. 85: 747–761, 2002. © 2002 Wiley-Liss, Inc.
Spectroscopic studies of carbons. XVII. Pyrolysis of polyvinylidene fluoride

Abstract Fourier transform photothermal beam deflection spectroscopy was used to examine chars produced by heating pure polyvinylidene fluoride (PVDF) in a N2 stream at temperatures ranging from 300 to 700°C. The infrared spectra obtained provide direct information about the destruction of the original polymer structure as well as its carbonization. PVDF exhibits a high thermal stability, characteristic of polyvinyl fluorides and spectroscopic evidence of the onset of degradation occurs near 300°C. Increasing the pyrolysis temperature results in a complex degradation process and a pyrolytic residue made up of largely aliphatic and fluoro-aromatic structures. The loss of most of the hydrogen-containing groups at temperatures in excess of 400°C results in a spectrum showing no vibrational features at wavenumbers >2000 cm−1 and a high temperature profile quite different from those previously observed for the polyvinyl chloride, bromide and fluoride chars. The possible mechanisms for the degradation of PVDF as suggested by the spectroscopic evidence is discussed in detail.
The Paranormal: A Selected Bibliography of Serials and Reference Works, with Commentary.

Despite the fact that paranormal subjects hold interest for a very large number of people, there apparently have been no related analyses of users' needs. I suggest that a well-intended library collection of works on the paranormal should seek a balance of perspectives, and feature a good selection of reference materials that will help patrons come to their own conclusions. A twelve-section bibliography of classic and current reference works and serials is provided both for selection purposes and to help librarians become better acquainted with the scope and range of preternatural studies.
Low-temperature impurity pairing in the frustrated 2D Ising model

We present exact results on the low-temperature behavior of the square lattice ±J Ising model, with a concentration c of ferromagnetic bonds and a concentration 1−c of antiferromagnetic bonds. We find that for T below a characteristic temperature T0, the system is “frozen” in the sense that its ground state properties coincide with measured quantities for systems of macroscopic size. We find that T0 is remarkably large, being roughly room temperature if J/kB ∼ 1000 K. We also study the effect on the free energy of various spatial arrangements of the ferromagnetic bonds.
Ab initio calculations on Pro-Ala and Pro-Gly dipeptides

Abstract The geometries of the dipeptides l -Pro- l -Ala, l -Pro- d -Ala and l -Pro-Gly were investigated by a grid scan ab initio calculation. The 6-31G basis set was used to estimate the effect of the alanyl side-chain on the conformation of the peptide backbone and to provide a computational basis for the interpretation of known physical-chemical properties of larger peptides that contain these dipeptides. These calculations furnish a direct quantum mechanical assessment of the energetic consequences of a methyl side-chain in the i + 2 position of a turn. The results of the calculation support the current view that the presence of a d -Ala residue in the i + 2 position favors a type II β-turn over a type I β-turn conformation, while l -Ala has the opposite effect. Total and relative energies for all the optimized conformations identified by the grid search are given and geometric parameters (bond lengths, bond angles and dihedral angles) and net atomic charges have been calculated.
The Infrared Spectra of Dichloroacetic Acid Derivatives: Characteristic Absorption Frequencies of the -CHCl2 Group

The infrared spectra of seven compounds containing the -CHCl2 group attached to various carbonyl functionalities have been carefully recorded under a variety of conditions. Group frequency ranges for the CH, CC, and CCl (two) stretching modes and two CH bending modes have been developed. With the exception of the CC stretching mode, these vibrations fall in rather narrow regions of the spectrum. The conformational equilibria present in chlorine-substituted acetic acid derivatives are reflected by their infrared spectra in various ways. The situation with regard to the observed carbonyl stretching frequencies as related to conformational equilibria is reviewed.
Cost analysis of the strengthening families program in reducing time to family reunification among substance-affected families

Abstract Decision makers typically face uncertainty in determining whether the outcomes of promising child welfare interventions justify the investment. Despite repeated calls for cost analysis in child welfare, original studies that evaluate the costs and effects of child welfare programs have been limited. Moreover, no cost analyses have focused on family reunification programs that address the needs of substance-affected families. The purpose of this study was to evaluate the costs and effects of a federally funded implementation of the Strengthening Families Program (SFP), a 14-week family training curriculum, on time to reunification with a substance-involved child welfare population. Based on event history analysis, we find the typical child participating in SFP spends 190 fewer days in out of home care when compared to a propensity score matched comparison group of children in out-of home care receiving treatment as usual. Re-entry rates between the two groups were not significantly different at follow-up. At an average out-of-home care rate of $86 per child per day in this state, SFP saves approximately $16,340 per participating child in out-of-home care costs. From a cost–benefit perspective, every $1 invested in SFP yields an average savings of $9.83 in this Midwestern demonstration.
Biomedical Applications of Proteomics. Jean-Charles Sanchez, Garry L. Corthals, and Denis F. Hochstrasser, editors. Weinheim: Wiley-VCH Verlag GmbH & Co., 2004, 462 pp., $165.00, hardcover. ISBN 3-527-30807-5.

Considering the rapid pace at which new applications of proteomics are appearing in the literature, this is a timely publication and would be a good resource for someone trying to get an overview of the field. There are 21 chapters, divided into seven parts, or sections: aspects in biomedical research; blood vessels; cancer; pharmaco-toxicology; infectious diseases; central nervous system; and mass spectrometry and bioinformatics. These sections fall into three larger groups: an introduction (part I), applications (parts II through VI), and a closing section with background information on technology and informatics (part VII). The introduction (part I) does an excellent job of presenting …
Bonding Preferences of C2X4-Bridged Bimetallic Transition Metal Complexes of Ti, Cu, and Ag

The bonding preference of transition metal species of general formula [(PH3)2M]2(mu-C2X4), where M = Cu or Ag and X = O, S, Se, or Te, and (Cp2Ti)2(mu-C2X4), where X = S or Se, are explored using density functional theory. The relative energies of metal binding to the bridging ligand in a dithiolene-like vs dithiocarbamate-like manner are evaluated. In all cases, the most stable structure corresponds to dithiolene-like (or side-side) bonding, consistent with the vast majority of these compounds which have been experimentally characterized. However, for M = Ag and X = S, Se, or Te, the two isomers are nearly degenerate.
Gene mapping and gene enrichment by the avidin-biotin interaction: use of cytochrome-c as a polyamine bridge

A modification of previously described methods of electron microscopic gene mapping and of gene enrichment based on the avidin-biotin interaction is presented. The modification consists of coupling cytochrome-c instead of pentane diamine to the oxidized 2', 3' terminus of an RNA by Schiff base formation and BH-4 reduction. The RNA-cytochrome-c conjugate is purified by a simple chromatographic procedure; several biotins are attached to the cytochrome moiety by acylation. The extended arm between biotin and RNA gives efficient electron microscopic gene mapping of DNA:RNA-biotin hybrids with avidin-ferritin and avidin-polymethacylate sphere labels and efficient gene enrichment by buoyant banding of DNA:RNA-biotin:avidin-spheres in CsCl. A 1400 fold enrichment (thus, 25% pure) and a 90% yield of long Drosophila DNA strands with 5S RNA genes is achieved.
Decreased adhesiveness of Alzheimer's disease fibroblasts: is amyloid β-protein precursor involved?

The adhesiveness of fibroblasts derived from Alzheimer's disease (AD) patients to a plastic substratum was assessed as the proportion of cells attached to a plastic dish bottom after a 30-minute incubation in culture medium of cells dissociated in ethylenediaminetetraacetic acid and was compared with the adhesiveness of normal fibroblasts from non-AD controls. It was found that the normal fibroblasts adhered better to plastic than did AD cells. This reduced adhesiveness was observed in fibroblasts derived from both sporadic and familial AD patients. Because of the possible involvement of amyloid beta-protein precursor (ABPP) in the process of cellular adhesion, the amount of ABPP messenger RNA was measured in these fibroblasts and was found to be decreased in the familial AD fibroblasts, although not in cells from sporadic AD patients. Furthermore, there were fewer molecules detected by an anti-ABPP antibody in conditioned media from familial AD fibroblasts as compared with media from control fibroblasts. Therefore, although it is possible that the reduced adhesiveness of familial AD fibroblasts may result from genetic deficits in ABPP gene expression, the reduced adhesiveness of sporadic AD fibroblasts most likely results from certain deficits in molecules other than the ABPP.
Studies on the Influence of the VP7 Gene on Rotavirus Replication

In a previous study using reassortant viruses, bovine rotavirus B223 VP7 protein enhanced the neutralization titers of some VP4 specific cross-reactive monoclonal antibodies (MAbs) (Xu and Woode, Virology, 1993). In this report, the influence of the B223 VP7 gene on the growth of reassortants was studied. The growth curves of three B223/69M reassortants with or without the B223 VP7 gene were compared. Reassortant M8, which has B223 VP7 on the genetic background of 69M, replicated as fast and to a similar titer as B223 and better than 69M. In contrast, the growth of reassortants B9, which has 69M VP7 on the B223 background, and of M46, which has B223 VP4 and VP6 on the 69M background, were poorer than B223. As B223 VP7 appeared to provide replication advantages, B223 was cultured as co-infections with each of the following viruses: Wa, 69M, H-2, SA11-4F, and NCDV followed by 20 subpassages. For co-infections with Wa, 69M, H-2, and SA11-4F, B223 VP7 gene was selected, in contrast to the B223/NCDV co-infection, when NCDV VP7 gene was selected. Other genes were also selected non-randomly, but varied among the five co-infection pairs. These data suggest in particular that B223 or NCDV VP7 protein can provide replication advantages to reassortant viruses, possibly by modifying VP4 to make it adsorb more efficiently to the cell receptors.
Progress in Disaster Planning and Preparedness Since 2001

THE SEPTEMBER 11, 2001, TERRORIST ATTACKS AND THE anthrax letters of 2001 were followed by a decade of major domestic and international disasters. Whether wrought by terrorist attacks, nuclear or chemical incidents, rapidly moving pandemics, record-breaking hurricanes, massive earthquakes, or other natural catastrophes, deadly disasters will continue to occur, and prompt and effective response will be required when lives are at stake. The good news is that disaster preparedness has improved during the past 10 years. For the health care community, 3 important developments are worth noting: (1) medical and public health professionals have joined the ranks of the disaster preparedness community; (2) the US federal government has increased its investment in preparedness, resulting in major improvements at the state and local levels; and (3) to an increasing extent, community participants who should be involved in disaster preparedness are getting involved.
The value of a writing center at a medical university.

Background: Students often enter graduate healthcare/biomedical schools with insufficient undergraduate instruction in effective writing, yet the ability to write well affects their career opportunities in health care and in scientific research. Purpose: The present study was conducted to determine the value and effectiveness of instruction by faculty with expertise in teaching writing at a writing center at an academic health science center. Methods: Two separate sources of data were collected and analyzed. First, an anonymous campus-wide survey assessed students’ satisfaction and utilization of the university's Writing Center. Second, a nonexperimental objective study was conducted comparing a subsample of students who used versus those who did not receive instruction at the Writing Center on quality of writing, as determined by an evaluator who was blind to students’ utilization status. Results: From the campus-wide survey, more than 90% of respondents who used the center (which was 26% of the student ...
Tumor markers CA 19-9 and CA 195 are also useful as markers for cystic fibrosis.

When monoclonal kits are used we can no longer detect highly elevated serum concentrations of carcinoembryonic antigen in cystic fibrosis (CF) patients as we could earlier (Pediatr Res 10:235–236, 1975). Instead, we find increased concentrations of CA 19-9 or CA 195 in the CF sera. The serum levels of CA 19-9 not only reflect the pulmonary condition of CF patients but also respond well to antibiotic therapy. Several lines of evidence suggest that the elevated serum concentration of CA 19-9 is derived from sputum and corresponds with the amount of sputum in the lung. Correlations between CA 19-9 and CA 195 in random and serial specimens from both patients with CF and patients with pancreatic carcinoma suggest that all sera contain heterogeneous, Lewis blood group-related epitopes and the proportions of various epitopes are different among individual patients. When monitored on multiple tumor markers, the pattern of CF is different from that of pancreatic carcinoma although both usually show elevated CA 19-9. Our study indicates that both CA 19-9 and CA 195 can be used as sensitive markers for the early detection of exacerbation in CF patients. © 1992 Wiley-Liss, Inc.
Castration affects territorial and sexual behaviour of free-living male lizards, Sceloporus jarrovi

Most of our knowledge of the importance of hormones in regulating behaviour comes from experiments conducted under laboratory conditions where the effects of non-hormonal cues in the social and physical environment have been intentionally minimized. The present study examined the effects of castration in free-living male mountain spiny lizards, Sceloporus jarrovi, that remained on their natural territories where full complement of non-hormonal cues from the social and physical environment was present. Castration reduced dramatically, but did not abolish, territorial and sexual behaviour of experimental males when compared to sham-operated controls. These results emphasize the importance of hormonal cues in regulating the behaviour of experienced adult animals subjected to the entire spectrum of cues from their natural social and physical environment. Certain behaviours, however, such as occupation of territories, were relatively unaffected by castration. This suggests that, in some cases, non-hormonal cues can either override or substitute for hormonal cues when the latter are removed.
Immune anaemias in patients with chronic lymphocytic leukaemia treated with fludarabine, cyclophosphamide and rituximab - Incidence and predictors

Immune anaemias (IA) [auto-immune haemolytic anaemia (AIHA) and pure red cell aplasia (PRCA)] are complications of chronic lymphocytic leukaemia (CLL). Fludarabine has been associated with AIHA, whereas both rituximab and cyclophosphamide have been used to treat this condition. Combining these agents with fludarabine may reduce the likelihood of AIHA. We report on the incidence, outcome and pretreatment predictors of IA in 300 patients treated with fludarabine, cyclophosphamide and rituximab (FCR). Nineteen patients (6·5%) developed IA [AIHA (5·8%), PRCA (0·7%)] on or after treatment with FCR. Most patients (82·4%) with AIHA had a negative direct antiglobulin test (DAT). Additional markers of haemolysis (indirect hyperbilirubinaemia, reticulocytosis, low haptoglobin and elevated lactate dehydrogenase levels) confirmed the presence of AIHA in these patients. The majority of patients responded to therapies including steroids, ciclosporin, i.v. immunoglobulin, etc. High pretreatment levels of beta-2 microglobulin predicted for development of IA. No haemolytic crisis was observed during FCR therapy in eight patients with AIHA prior to FCR. Thus, the incidence of IA among CLL patients treated with FCR was comparable with historical rates. The diagnosis of AIHA can be considered even if the DAT is negative. Pre-existing AIHA need not preclude front-line FCR therapy.
Viewpoint-popularity-driven uplink scheduling of multi-camera sensor arrays

A decentralized camera array records a 3D scene of interest simultaneously, from different perspectives. The captured video signals need to be transmitted over a shared wireless channel to a central station. The gathered data is then streamed to a collection of clients interested in experiencing the scene interactively. I design an optimization framework that allows for sharing the transmission resources of the wireless medium such that the average video quality over the client population is maximized. I consider scheduling the uplink resources either at the view or packet level. That is, in the first case, the central station partitions the channel capacity across a select subset of views that are transmitted in their entirety. In the second case, the station coordinates the packet transmissions of every sensor such that the aggregate data rate over the wireless channel does not exceed its capacity. I formulate algorithms that solve the optimization either exactly or approximatively, at lower complexity. I examine their transmission efficiency via simulation experiments that show a considerable improvement over reference methods. I also study the impact of viewpoint popularity, as governed by the clients that interact with the scene, on the operation of the optimization.
Immunological evidence that anemone repair proteins include replacement linkages

Abstract In response to damage to hair bundles caused by exposure to calcium free buffers, sea anemones secrete large protein complexes named ‘repair proteins’ that rapidly restore structural integrity and function to hair bundles. A specific chromatographic fraction of the repair protein mixture, named ‘fraction β’, has biological activity comparable to the complete repair protein mixture (Watson et al., 1998, Hear. Res. 115, 119–128). In this study, we find that polyclonal antibodies raised against deglycosylated fraction β specifically bind fraction β on Western blots. Anti-fraction β delays the normal recovery of vibration sensitivity in experimental animals (i.e., those with hair bundles damaged by calcium free buffers). Moreover, anti-fraction β disrupts vibration sensitivity in control animals (i.e., those with healthy hair bundles). Experimentally damaged hair bundles subsequently exposed to repair protein and then processed for immunoelectron microscopy show labeled linkages interconnecting stereocilia of the hair bundle. Immunofluorescence microscopy confirms strong labeling of hair bundles treated with repair proteins and only weak labeling of tips of hair bundles from control animals. Immunofluorescence microscopy indicates stores of repair proteins in gland cells of the body column in control animals and in gland cells of the mouth in experimental animals. Repair biological activity is confirmed in column purified homogenates of these tissues. Apparently repair proteins are delivered to damaged hair bundles in mucus carried by beating cilia.
The updating of object-position binding in visual short-term memory

Introduction The object file framework of Kahneman et al. (1992) holds that the representation of an object’s surface features (e.g., color or shape) is bound to a spatial index marking the location of that object. When an object moves, the spatial index is updated to reflect the changed position, and the surface feature information comes to be associated with the new location. Such a mechanism could enable the visual system to establish object correspondence across changes such as object motion or across disruptions such as eye movements.
Long-time properties of random walks with a single trap

For both Brownian and enhanced random walks, we can distinguish between systems where the random walker returns to the origin with certainty, and where the random walker may escape from the trapping origin with a probability strictly larger than zero. Examples for the first case are Brownian walks in one and two dimensions, where it is known that the asymptotic probability $f(t)$ to be trapped at time $\stackrel{\ensuremath{\rightarrow}}{t}\ensuremath{\infty}$ behaves differently from the asymptotic probability $p(t)$ to pass through the origin in the same system without trap. We also find this result for L\'evy flights in one dimension with the exponent of the characteristic function \ensuremath{\geqslant}1. On the other hand, we compute $p(t)$ and $f(t)$ for various systems with a nonzero escape probability. In particular, we consider an anisotropic walk, which behaves Brownian in one direction and executes L\'evy flights along the second direction. For these cases we are able to prove that $f(t)$ and $p(t)$ follow the same inverse power law asymptotically, the ratio given by the squared escape probability.
Input-output relations of finite memory systems

Finite memory finite-state machines have received considerable attention recently for at least two reasons—all linear finite-state machines have been shown to have finite memory and finite memory machines find useful applications in encoders and decoders used in communication. In this paper the input-output relations of finite memory machines are studied and tight bounds on the order of the set of input-output sequences of a finite length l generated by a binary finite memory machine are obtained. An important class of finite memory machines called complete finite memory machines is enumerated. The “sequential relations” of finite memory machines are examined and it is shown that a finite set of input-output sequences characterizes a nondegenerate finite memory machine uniquely up to equivalence.
Design unbiased estimation in line intersect sampling using segmented transects

In many applications of line intersect sampling, transects consist of multiple, connected segments in a prescribed configuration. The relationship between the transect configuration and the selection probability of a population element is illustrated and a consistent sampling protocol, applicable to populations composed of arbitrarily shaped elements, is proposed. It is shown that this protocol obviates the arbitrary practice of treating multiple intersections of a single particle as independent probabilistic events and preserves the design-unbiasedness of Kaiser’s (1983, Biometrics 39, 965–976) conditional and unconditional estimators, suitably generalized to segmented transect designs. The relative efficiency and utility of segmented transect designs are also discussed from a fixed population perspective.
Inhibition of transcription factor NF-κB signaling proteins IKKβ and p65 through specific cysteine residues by epoxyquinone A monomer: Correlation with its anti-cancer cell growth activity

Transcription factor NF-kappaB is constitutively active in many human chronic inflammatory diseases and cancers. Epoxyquinone A monomer (EqM), a synthetic derivative of the natural product epoxyquinol A, has previously been shown to be a potent inhibitor of tumor necrosis factor-alpha (TNF-alpha)-induced activation of NF-kappaB, but the mechanism by which EqM inhibits NF-kappaB activation was not known. In this report, we show that EqM blocks activation of NF-kappaB by inhibiting two molecular targets: IkappaB kinase IKKbeta and NF-kappaB subunit p65. EqM inhibits TNF-alpha-induced IkappaBalpha phosphorylation and degradation by targeting IKKbeta, and an alanine substitution for Cys179 in the activation loop of IKKbeta makes it resistant to EqM-mediated inhibition. EqM also directly inhibits DNA binding by p65, but not p50; moreover, replacement of Cys38 in p65 with Ser abolishes EqM-mediated inhibition of DNA binding. Pretreatment of cells with reducing agent dithiothreitol dose-dependently reduces EqM-mediated inhibition of NF-kappaB, further suggesting that EqM directly modifies the thiol group of Cys residues in protein targets. Modifications of the exocyclic alkene of EqM substantially reduce EqM's ability to inhibit NF-kappaB activation. In the human SUDHL-4 lymphoma cell line, EqM inhibits both proliferation and NF-kappaB DNA binding, and activates caspase-3 activity. EqM also effectively inhibits the growth of human leukemia, kidney, and colon cancer cell lines in the NCI's tumor cell panel. Among six colon cancer cell lines, those with low amounts of constitutive NF-kappaB DNA-binding activity are generally more sensitive to growth inhibition by EqM. Taken together, these results suggest that EqM inhibits growth and induces cell death in tumor cells through a mechanism that involves inhibition of NF-kappaB activity at multiple steps in the signaling pathway.
Direct Monte Carlo computation of time-resolved fluorescence in heterogeneous turbid media

We show that a multiexponential model for time-resolved fluorescence allows the use of an absorption-perturbation Monte Carlo (MC) approach based on stored photon path histories. This enables the rapid fitting of fluorescence yield, lifetimes, and background tissue absorptions in complex heterogeneous media within a few seconds, without the need for temporal convolutions or MC recalculation of photon path lengths. We validate this method using simulations with both a slab and a heterogeneous model of the mouse head.
Explaining synchrony in feed-forward networks

In any scientific theory, the conceptual framework already determines the nature and possible scope of the results. Oversimplification prevents an adequate description of the system, whereas too detailed a description obscures the fundamental principles behind the observed phenomena in addition to misspending time and resources. In theoretical neuroscience, this is an important issue because the description level varies widely from detailed biophysical descriptions to abstract computational models. We discuss the question of the appropriate modeling level in the context of a recent report on synchrony in iteratively constructed feed-forward networks of rat cortex pyramidal neuron somata (Reyes, 2003).
Radioisotope Technique for Estimating Lady Beetle Consumption of Tobacco Budworm Eggs and Larvae

Females of the tobacco budworm, Heliothis virescens (F.), were fed Phosphorus-32 (in NaH232PO4)in a 10% sucrose solution. Eggs and larvae of the moths were assayed for radioactivity before feeding them to the adult lady beetles, Coleomegilla maculata DeGeer. The adults were assayed for radioactivity each day for 10 days after consumption of the eggs or larvae. Radioactivity levels in the lady beetles showed a gradual decline each day after consumption of egg or larvae. Prediction equations from regression analysis indicate that the number of eggs or larvae eaten by adult C. maculata can be predicted in laboratory or field studies after determining radioactivity of H. virescens eggs or larvae prior to lady beetle consumption.
Immature type-1 astrocytes suppress glial scar formation, are motile and interact with blood vessels

Previous studies have shown that immature but not mature astrocytes have the capacity to suppress glial scar formation and enhance axon outgrowth when transplanted into the adult mouse brain. We report here that glial scar formation is suppressed following transplantation of purified immature but not mature cultured type-1 rat cortical astrocytes into the adult rat brain. To examine the fate of transplanted cells, cultured astrocytes were labeled with either fluorescent beads or BSA-conjugated colloidal gold and traced after transplantation using both light and electron microscopy. While both immature and mature astrocytes survived transplantation, mature astrocytes appeared more susceptible to phagocytosis by cells of the immune system than immature astrocytes. Furthermore, while mature astrocytes were restricted to the region of the implant, immature astrocytes migrated into the surrounding CNS and became closely associated with host blood vessels. Such blood vessels were impermeable to the diffusion of systematically applied Evans blue dye. To determine whether immature astrocytes were intrinsically more motile than mature astrocytes, their rate of translocation was compared in vitro. Immature astrocytes translocated more than twice as fast as mature astrocytes. This ability of immature astrocytes to translocate throughout the host CNS and become associated with blood vessels may be a major factor in their ability to suppress glial scar formation in the adult animal.
On the structure and chromosome location of the 72- and 92-kDa human type IV collagenase genes.

Abstract The 72- and 92-kDa type IV collagenases are members of a group of secreted zinc metalloproteases. Two members of this family, collagenase and stromelysin, have previously been localized to the long arm of chromosome 11. Here we assign both of the two type IV collagenase genes to human chromosome 16. By sequencing, the 72-kDa gene is shown to consist of 13 exons, 3 more than have been reported for the other members of this gene family. The extra exons encode the amino acids of the fibronectin-like domain which has so far been found in only the 72- and 92-kDa type IV collagenases. The evolutionary relationship among the members of this gene family is discussed.
Epidural steroid injections: An update on mechanisms of injury and safety

Epidural steroid injections (ESIs) are the most commonly performed intervention in the United States to manage chronic and subacute low back and neck pain with radiculopathy. ESIs have been used for decades for the treatment of discogenic and osteoarthritic radicular conditions originating from the cervical, thoracic, and lumbar spine, as well as spondylosis, nonspecific radiculitis, and spinal stenosis. With the ever-increasing use of epidural steroids, there has been a disproportionate increase in popularity of transforaminal ESIs in particular. Since 2002, there has been a growing body of largely transforaminal epidural steroid case report literature that describes paralysis, stroke, and death that immediately follows the performance of these procedures. These complications are thought to be related to a combination of factors, which may include the technique used, underlying pathophysiology that is being treated, anatomical variations in the blood supply, as well as the specific injectate used. This article discusses the pathogenesis of these complications and puts the role of steroids in their causation into perspective.
Genetic, antigenic and biological differences between strains of hepatitis A virus.

Abstract Recent studies have documented a considerable degree of genetic divergence among wild-type hepatitis A virus (HAV) strains recovered from different geographical locations. Human HAV strains can be grouped into four genotypes (I, II, III and VII) and unique simian strains belong to three additional genotypes (IV, V and VI). Between each of these genotypes, the nucleotide sequence varies at 15–25% of base positions in the P1 region. Despite this, there is good evidence that most, if not all, human strains of HAV are closely related antigenically. In contrast, although simian strains recovered from Old World monkeys are cross-reactive in immunoassays employing polyclonal antibodies, these strains have significant antigenic differences from human HAV strains. Nonetheless, because biological differences in the host range of these strains apparently preclude significant human infection, this is unlikely to pose a problem in controlling HAV infections with active immunization. Inactivated and attenuated vaccines produced from genotype I human strains (HM175 or CR326) are likely to provide protection against all relevant human HAV strains.
Glucocorticosteroid regulation of prostaglandin biosynthesis in human myometrial smooth muscle cells in monolayer culture.

In the present investigation, we evaluated the production of prostaglandins by human myometrial smooth muscle cells maintained in monolayer culture in the absence or presence of glucocorticosteroids. In the presence of cortisol (10−7M) or dexamethasone (10−8M), the rate of production of prostacyclin (PGI2) by these cells was decreased significantly. The glucocorticosteroid-mediated inhibition of prostaglandin production was attenuated when cortisol-21-mesylate (10−6M), a glucocorticosteroid antagonist, was present in the culture medium. The rate of conversion of radiolabeled arachidonic acid to radiolabeled prostaglandins as determined by use of sonicates of myometrial cells and optimal assay conditions, however, was not affected significantly by treatment with cortisol or dexamethasone in concentrations sufficient to inhibit prostaglandin formation by more than 80%. These findings are suggestive that glucocorticosteroids act in human myometrial smooth muscle cells in culture to inhibit prostaglandin formation by way of a receptor-mediated process that does not involve inhibition of enzyme activities that are involved in the biosynthesis of prostaglandins, i.e. the conversion of arachidonic acid to prostaglandin.
The steady part of the secular variation of the Earth's magnetic field

The secular variation of the Earth's magnetic field results from the effects of magnetic induction in the fluid outer core and from the effects of magnetic diffusion in the core and the mantle. Adequate observations to map the magnetic field at the core-mantle boundary extend back over three centuries, providing a model of the secular variation at the core-mantle boundary. Here we consider how best to analyze this time-dependent part of the field. To calculate steady core flow over long time periods, we introduce an adaptation of our earlier method of calculating the flow in order to achieve greater numerical stability. We perform this procedure for the periods 1840-1990 and 1690-1840 and find that well over 90 percent of the variance of the time-dependent field can be explained by simple steady core flow. The core flows obtained for the two intervals are broadly similar to each other and to flows determined over much shorter recent intervals.
The rate of energy loss due to ionization and range-energy relation in CsI

Abstract The rate of energy loss due to ionization in CsI has been calculated for muon, pion, kaon and proton in the energy interval 10 1 −10 5 MeV, taking into consideration both the shell correction and density effect terms. The ranges of muon, pion, kaon, proton, deuteron, triton, 3 He and 4 He have also been calculated upto 10 4 MeV. The fwhm and most probable energy loss in thin absorbers have been calculated for four different thicknesses of CsI (0.2, 0.5, 1.0 and 2.54 cm) covering the range of interest in both high energy physics and cosmic rays.
Contextualizing Parent Education Programs in Urban Schools The Impact on Minority Parents and Students

This article describes a collaborative effort among a university college of education, its graduate school of social work and a community school to develop a culturally responsive parent education/involvement program. Educators and social workers worked cooperatively to provide a model for involvement and education that validated the cultural frame of reference, values, and heritage of the participants. As a result of participating in this type of program, the participants indicated they had more knowledge and confidence, which enabled them to interact more effectively with their children at home, as well as with teachers and others at the school.