cssi/SciSciGPT-SciSciNet huggingface dataset:
Threshold photoperiods for the induction of short day traits in collared lemmings (Dicrostonyx groenlandicus).

When exposed to short photoperiod collared lemmings undergo a number of physiological and morphological changes including an increase in body weight, a change in body composition, development and enlargement of the bifid “digging” claw, and a molt to a white winter pelage. We investigated the threshold photoperiods for the induction of these traits in male and female lemmings born and raised under a 22L:2D photoperiod and transferred at weaning (19 days of age) to various other photoperiods. Male lemmings showed the characteristic increase in body weight when exposed to 16 hr of light or less per day whereas females required a photoperiod of 14 hr of light or less per day to elict an increase in body weight. The thresold photoperiods for the increase in bifid claw size were 16 and 18 hr of light per day in male and female lemmings, respectively. The molt to the white winter pelage began under a longer photoperiod in females (16L:8D) than in males (14L:10D). Testes and seminal vesicles were significantly inhibited by photoperiods of 22L:2D and 20L:4D. Likewise, uterine weights were inhibited by maintenance on a photoperiod of 22L:2D. Taken together, these data show that the threshold photoperiods for the induction of the short day traits in collared lemmings are both trait- and sex-dependent. These observations also suggest that under some conditions, exposure to long photoperiods can inhibit sexual maturation. © 1993 Wiley-Liss, Inc. © 1993 Wiley-Liss, Inc.
Analysis of recombinant cytokines in human body fluids by immunoaffinity capillary electrophoresis

An immunoaffinity capillary electrophoresis (ICE) system for rapidly quantifying recombinant cytokines in human body fluids has been developed. Cytokines within biological fluids were labeled with a red light emitting fluorochrome and injected into the capillary. Selected cytokines were captured by immobilized antibodies on the internal surface of the capillary, and held while unbound materials were purged. The cytokines were then eluted electrophoretically in acidic buffer. Individual cytokine peaks were detected by on-line laser-induced fluorescence detection coupled to a computerized fiber-optic spectrometer, and analyzed by integration of the eluted peaks. The comparison of the results of ICE to routine assays used for these cytokines demonstrates that ICE provides a fast and accurate procedure for defining these cytokines in complex biological samples. Immunoaffinity separations can be used for any material to which a specific antibody can be raised, making this procedure applicable to a wide range of molecules of biomedical interest.
WATERSHED SCALE INVENTORY OF EXISTING RIPARIAN BUFFERS IN NORTHEAST MISSOURI USING GIS

An observational study was conducted at the watershed scale using land cover (vegetation) data to assess the absence or presence of riparian buffers in three northeastern Missouri watersheds. Forests and grasslands lying within a 61 m (200 ft) parallel band directly adjacent to streams were considered "buffers" for improving or protecting water quality and were characterized according to their length, width, and vegetation type. Results indicated that riparian buffers were abundant throughout the watersheds but were typically narrow along first-order and second-order streams; in many cases they may not have been wide enough to provide adequate stream protection. At least 90 percent of all streams had buffer vegetation immediately adjacent to the streambanks, but as few as 31 percent of first-order streams had buffers extending to 61 m from the stream on at least one side. On-site evaluations are needed to determine the condition of these forests and grasslands and their ability to process nonpoint source pollutants. The results will be useful for providing natural resource managers with knowledge of current watershed conditions as well as in identifying specific locations for future conservation efforts within each watershed.
Is there a Role for Radical Surgery in Advanced Gallbladder Carcinoma

Forty-four patients with advanced gallbladder carcinoma (18 with stage pT3 and 26 with stage pT4 of the Union Internacional Contra la Cancrum classification) were aggressively managed by extended heptatic resection in 33 patients, bile duct resection in 28, pancreaticoduodenectomy in seven, gastrointestinal resection in eleven and portal vein resection and reconstruction in seven. Adjacent organ involvement was classified as follows: type I, hepatic involvement with or without gastrointestinal invasion (Ia, Ib); type II, bile duct involvement with or without gastrointestinal invasion (IIa, IIb); type III, hepatic and bile duct involvement with or without gastrointestinal invasion (IIIa, IIIb); type IV, gastrointestinal involvement without hepatic or bile duct invasion. Fourteen of 15 patients with type I tumours had a curative resection compared with seven of 26 with type III lesions (P< 0.0001). The surgical mortality rate was two of 15 patients with type I tumours, seven of 26 with type III tumours and nine of 44 for the whole group. The long-term survival rate after curative resection was four and two of 23 at 3 and 5 years respectively, significantly better than two and none of 21 at I and 2 years after non-curative resection (P<0.01). The survival rate after curative resection for patients with type I tumours was four and two of 14 at 3 and 5 years respectively, significantly better than for other types (P<0.05). This classification of advanced gallbladder carcinoma according to involvement of adjacent organs might be helpful in planning surgery for this condition; in particular, type I tumours should be treated by a radical surgical procedure to achieve a favourable outcome.
On certain morphisms of sequential dynamical systems

We study a class of discrete dynamical systems that consist of the following data: (a) a finite (labeled) graph Y with vertex set {1,...,n}, where each vertex has a binary state, (b) a vertex labeled multi-set of functions (F"i","Y:F"2^n->F"2^n)"i and (c) a permutation @p@?S"n. The function F"i","Y updates the binary state of vertex i as a function of the states of vertex i and its Y-neighbors and leaves the states of all other vertices fixed. The permutation @p represents a Y-vertex ordering according to which the functions F"i","Y are applied. By composing the functions F"i","Y in the order given by @p we obtain the sequential dynamical system (SDS)[F"Y,@p]=@?i=1nF"@p"("i")","Y:F"2^n@?F"2^n.Let G[F"Y,@p] be the graph with vertex set F"2^n and edge set {(x,[F"Y,@p](x))|x@?F"2^n}. An SDS-morphism between [F"Y,@p] and [F"Z,@s] is a triple (@f,@h,@F), where @f:Y@?Z is a graph-morphism, @h:S"|"Z"|@?S"|"Y"| is a map such that @h(@s)=@p and @F is a digraph-morphism @F:G[F"Z,@s]@?G[F"Y,@p]. Our main result is that locally bijective graph-morphisms (coverings) between dependency graphs of SDS naturally induce SDS-morphisms. We show how these SDS-morphisms allow for a new proof for the upper bound on the number of inequivalent SDS obtained by only varying their underlying permutations. Here, two SDS are called inequivalent if they are inequivalent as dynamical systems. Furthermore, we apply our result in order to obtain phase space properties of SDS.
Hormonal regulation of hippocampal spine synapse density involves subcortical mediation.

Abstract It is well established that estrogen has positive effects on the density of pyramidal cell spines in the hippocampal CA1 subfield. This study explored whether afferent connections of the hippocampus that come from estrogen-sensitive subcortical structures, including the septal complex, median raphe and supramammillary area, play a role in this estrogen-induced hippocampal synaptic plasticity. These particular subcortical structures have major influences on hippocampal activity, including theta rhythm and long-term potentiation. The latter also promotes the formation of new synapses. All of the rats were ovariectomized; the fimbria/fornix, which contains the majority of subcortical efferents to the hippocampus, was transected unilaterally in each, and half of the animals received estrogen replacement. Using unbiased electron microscopic stereological methods, the CA1 pyramidal cell spine synapse density was calculated. In the estrogen-treated rats, contralateral to the fimbria/fornix transection, the spine density of CA1 pyramidal cells increased dramatically, compared to the spine density values of both the ipsilateral and contralateral hippocampi of non-estrogen-treated animals and to that of the ipsilateral hippocampus of the estrogen replaced rats. These observations indicate that fimbria/fornix transection itself does not considerably influence CA1 area pyramidal cell spine density and, most importantly, that the estrogenic effect on hippocampal morphology, in addition to directly affecting the hippocampus, involves subcortical mediation.
Construction of centrosomes and spindle poles by molecular motor-driven assembly of protein particles

Centrosomes and other microtubule organizing centers are the largest non-membranous organelles in most cells. This morphologically diverse class of organelles shares a common ability to nucleate and organize microtubules in interphase and participates in the formation of mitotic spindles during cell division. This review summarizes recent evidence suggesting that assembly of centrosomes and mitotic spindle poles require transport of large protein particles along microtubules by the molecular motor cytoplasmic dynein.
The role of T cells in cutaneous autoimmune disease

T cells assume a fundamental function in immunosurveillance and maintenance of the cutaneous immune barrier, yet derangement of their requisite role effects a range of cutaneous autoimmune diseases with significant associated morbidity. While blistering skin diseases, such as pemphigus vulgaris (PV), pemphigus foliaceus (PF) and bullous pemphigoid (BP) are mediated by antibodies directed against autoantigens found in the skin, recent evidence has shown that T cell activation is crucial for the initiation and coordination of this humoral response. Non-blistering skin diseases, such as alopecia areata (AA), vitiligo (VL) and psoriasis (PS) are increasingly believed to be directly mediated by the activities of autoreactive T cells. Here, we examine T lymphocyte control of antibody-mediated and cell-mediated processes involved in the pathoimmunology of the above mentioned skin diseases.
Formation of yeast mitochondria III: Biochemical properties of mitochondria isolated from a cytoplasmic petite mutant

A number of biochemical properties of mitochondria from a cytoplasmic petite mutant ofSaccharomyces cerevisiae with an extremely high adenine plus thymine content have been studied. When such particles are isolated by means of standard procedures developed for use with wild-type yeasts they are grossly contaminated by non-mitochondrial membrane fragments. Further enrichment of mitochondria is achieved by non-equilibrium centrifugation in sucrose gradients. Throughout this purification procedure the particles can be shown to retain an outer limiting, as well as a non-cristate inner membrane. In many of their morphological and physical features (size, shape, buoyant density) they resemble mitochondria isolated from the wild type. Although enzymes of the respiratory chain are absent from the mutant particles, their content ofl-malate dehydrogenase, NADP-dependent isocitrate dehydrogenase, and ATPase is comparable to that found in the wild type. The mitochondrial ATPase in this mutant strain is cold stable, oligomycin insensitive, Dio-9 sensitive, and susceptible to inhibition by the F1 inhibitor of beef heart. The enzyme can be rendered cold labile by its detachment from the membrane, followed by fractionation with protamine sulfate and ammonium sulfate. The existence of mutant particles that are incapable of function in oxidation and phosphorylation but resemble their functional homologues in many other ways raises the possibility that mitochondria are required in the cellular economy for purposes not directly linked to oxidative phosphorylation and electron transport. This hypothesis has led us to suggest that, contrary to models currently under discussion, mitochondria did not evolve as a consequence of endosymbiosis. We propose as an alternative that the mitochondrial organelle evolved as a means of improvement of existing subcellular structures in the primordial (perhaps eukaryotic) cell. Partial autonomy may thus constitute a relatively recent modification; the present-day mitochondrial genome had its origin in nuclear DNA and may have been amplified in a manner not unlike the amplification of ribosomal RNA cistrons in developing oocytes ofXenopus.
Characterization of Polycrystalline Silicon-Germanium Film Deposition for Modularly Integrated MEMS Applications

The deposition of in situ boron-doped polycrystalline silicon-germanium (poly-SiGe) films in a conventional low-pressure chemical-vapor deposition reactor has been characterized using the design of experiments method. The dependencies of deposition rate, resistivity, average residual stress, strain gradient, and wet etch rate in hydrogen peroxide solution are presented. Structural layer requirements for general microelectromechanical system applications can be met within the process temperature constraint imposed by complementary metal-oxide-semiconductor (CMOS) electronics. However, residual stress and strain gradient requirements for inertial sensor applications will be difficult to meet with a single homogeneous layer of poly-SiGe that is about 2 mum thick. By correlating stress depth profile measurements with cross-sectional transmission electron microscopy images, we conclude that the large strain gradient is due to highly compressive stress in the lower (initially deposited) region of the film. For films deposited at very low temperature (near the range of amorphous film deposition), in situ boron doping enhances film crystallinity and reduces the strain gradient
EFFECT OF EPSILON-AMINOCAPROIC ACID ON DEPOSITION OF RADIOIODINATED FIBRINOGEN AND ANTIBODIES TO FIBRINOGEN IN TURPENTINE-INDUCED ABSCESSES ON THE RAT.

SummaryAn investigation of the effect of orally administered 5% e-aminocaproic acid (EACA) in drinking water on the behavior of intravenously injected I131-fibrinogen and I131-antibody to fibrinogen was carried out in both normal rats and rats with abscesses produced by subcutaneous injection of turpentine. Treatment with EACA had no demonstrable effect on either whole-body retention or blood half-life of either I131-nbrinogen or I131-antibody in normal rats. The most striking effect of EACA was to decrease greatly the rate of removal of I131 from the abscess area. Six days after injection of I131-nbrinogen, 11% of the injected I131 was still present in single abscesses of EACA treated rats while in non-EACA treated rats the I131 retained was less than 1% of the injected dose. Similarly, 6 days after injection of I131-antibody 20% of the injected I131 was present in abscesses of EACA treated animals and only 4% in abscesses of rats not receiving EACA. In animals with 2 abscesses, the amount of I131 deposi...
How Poverty and Segregation Impact Child Development: Evidence from the Chicago Longitudinal Study

ABSTRACT Living in poor and segregated neighborhoods has detrimental effects on children's life chances. In an attempt to improve poor children's outcomes, the Chicago Child-Parent Center (CPC) program engages parents and their children in kindergarten and the primary grades to enhance academic achievement. This study looks further at the children's social and emotional development. In particular, it examines the moderating effect of poverty and segregation and the program's ability to enhance developmental outcomes for youth in early adolescence. Using a quasi-experimental research design, findings show that, above and beyond the main CPC impacts, those children living in high poverty and highly segregated areas fare additionally well through their CPC program participation. Effect sizes range from about 0.15 to about 0.40, depending on the outcome
Multielement Operation of the Cathode Ray Oscillograph

With the aid of specially designed auxiliary devices, the cathode ray oscillograph may be operated as a multielement instrument, in circuits that permit of the repeated application of the wave to be observed. The number of waves that may be traced with apparent simulataneity on the oscillograph screen is limited only by the complexity of the control circuit and the crowding of the various curves on the relatively small screen.
Flicker noise due to grain boundaries in n-type Hg1−xCdxTe☆

Abstract Flicker noise was measured between adjacent contacts a−b and b−c of n-type Hg0.61Cd0.39Te photoconducting samples. The region between contacts a and b had no grain boundary, whereas the region between contacts b and c had a grain boundary. When the data were corrected for the differences in the resistances between the contacts a−b and b−c, it was found that the grain-boundary section had four times as much noise as the no-grain-boundary section for the particular geometry involved.
Study of natural photonic crystals in beetle scales and their conversion into inorganic structures via a sol–gel bio-templating route

The origin of the structural colors from several different examples of the weevil and longhorn families (Curculionidae and Cerambycidae, respectively) was investigated by structural and optical characterization techniques. A range of interesting three-dimensional photonic crystal structures operating at visible wavelengths was discovered, including both disordered and ordered non-close-packed lattices of cuticular spheres and bicontinuous diamond-based architectures. The discovered photonic structures display a large variation in lattice constants and dielectric filling fractions and thereby create optical reflectance colors spanning the entire visible range. To transform these bio-polymeric photonic crystals into heat and photo-stable inorganic structures, a low-temperature bio-templating method was developed. Using organic–inorganic hybrid silica sol–gel infiltration–templation chemistry combined with acid-etching template removal, stable inverse photonic structures were fabricated. The inverse structures display good structural quality and vivid reflection properties.
Radiobiological significance of beamline dependent proton energy distributions in a spread-out Bragg peak

Similar target doses can be achieved with different mixed radiation fields, i.e., particle energy distributions, produced by a practical proton beam and a range modulator. The dose delivered in particle therapy can be described as the integral of fluence times the total mass stopping power over the particle energy distributions. We employed Monte Carlo simulations to explore the influence on the relative biological effectiveness (RBE) of the energy and the energy spread of the proton beam incident on a range modulator system. Using different beams, the conditions of beam delivery were adjusted so that similar spread out Bragg peak (SOBP) doses were delivered to a simulated water phantom. We calculated the RBE for inactivation of three different cell lines using the track structure model. The RBE depends on the details of the dose deposition and the biological characteristics of the irradiated tissue. Our calculations show that, for differing beam conditions, the corresponding differences in the total mass stopping power distributions are reflected in differences in the RBE. However, these differences are remarkable only at the very distal edge of the SOBP, for low doses, and/or for large differences in beam setup.
AIDS research and policy decisions

Abstract The pressures on policy makers to do something about AIDS (Acquired Immunodeficiency Syndrome) is powerful. The problem is that the scientific information available may not be sufficient or of sufficiently good quality to justify any particular action, and the risk of doing something that might in the long run be harmful is not trivial. Scientists need to develop criteria for assessing the quality and sufficiency of the information available and that they might provide.
Sequence analysis and phylogenetic reconstruction of the genes encoding the large and small subunits of ribulose-1,5-bisphosphate carboxylase/oxygenase from the chlorophyll b-containing prokaryote Prochlorothrix hollandica.

Prochlorophytes similar toProchloron sp. andProchlorothrix hollandica have been suggested as possible progenitors of the plastids of green algae and land plants because they are prokaryotic organisms that possess chlorophyllb (chlb). We have sequenced theProchlorothrix genes encoding the large and small subunits of ribulose-1,5-bisphosphate carboxylase/oxygenase (rubisco),rbcL andrbcS, for comparison with those of other taxa to assess the phylogenetic relationship of this species. Length differences in the large subunit polypeptide among all sequences compared occur primarily at the amino terminus, where numerous short gaps are present, and at the carboxy terminus, where sequences ofAlcaligenes eutrophus and non-chlorophyllb algae are several amino acids longer. Some domains in the small subunit polypeptide are conserved among all sequences analyzed, yet in other domains the sequences of different phylogenetic groups exhibit specific structural characteristics. Phylogenetic analyses ofrbcL andrbcS using Wagner parsimony analysis of deduced amino acid sequences indicate thatProchlorothrix is more closely related to cyanobacteria than to the green plastid lineage. The molecular phylogenies suggest that plastids originated by at least three separate primary endosymbiotic events, i.e., once each leading to green algae and land plants, to red algae, and toCyanophora paradoxa. TheProchlorothrix rubisco genes show a strong GC bias, with 68% of the third codon positions being G or C. Factors that may affect the GC content of different genomes are discussed.
The surface atomic oxyradical mechanism for Ag-catalyzed olefin epoxidation☆

Abstract We report comprehensive, quantitative, ab initio theoretical estimates for the energetics involved in the Ag-catalyzed epoxidation of olefins. From these estimates, a detailed mechanism is proposed. This mechanism (based on theoretical quantum chemical studies of the interaction of atomic and molecular adsorbates with clusters of Ag atoms) proposes that a surface atomic oxyradical anion is the active oxygen species for forming epoxide. This mechanism explains the role of electronegative (Cl − ) and electropositive (Cs + ) promoters and explains why selectivity (toward epoxide) is far higher for ethylene than for propene and other higher olefins. Recent experiments which suggested O 2(ad) as the active species are reinterpreted within the context of this new atomic oxygen radical mechanism.
Increased Release of Amino Acids from Hat Thymus After Cortisol Administration

Adrenalectomized male rats were given 1 mg of cortisol subcutaneously; then, after a period of time, usually 2 hr, the animals were killed and slices were prepared from their thymus glands. When these slices were incubated in a buffered salt solution, there was an apparent release of amino acids and nucleotidelike materials from the tissue, a release that proceeded at a greater rate with slices from cortisoltreated rats than with slices from control animals.animals. The response of amino acids to cortisol appeared to be specific for the glucocorticoids; it was seen consistently at 120 min but not at 60 min following injection of cortisol. Two hr after cortisol treatment, there was no significant elevation of amino acids in the thymic tissue; there was slight or no depression of incorporation amino acids into proteins of the slices, and the loss of protein from the slices was not enhanced. (Endocrinology 80: 288, 1967)
‘Intimate’ Talk in Russian: Human Relationships and Folk Psychotherapy

The paper explores and describes communicative aspects of ‘intimate’ relations in Russian. Using data from the Russian National Corpus, it illuminates the meanings of the social category terms drug ‘close friend’, rodnye ‘dear/kin’ and blizkie ‘close (ones)’ and demonstrates their relationship to the culturally salient terms dusa ‘soul, heart’ and sokrovennyj ‘innermost, dear, hidden’. The paper contributes to understanding of Russian relationships and social cognition and establishes connections between the meanings of these terms and selected Russian ways of talking. The Natural Semantic Metalanguage (NSM) is used to formulate semantic explications of the terms and cultural scripts.
Dielectric Properties of BaTi O 3 Single Crystals in the Paraelectric State from 1 kc/sec to 2000 Mc/sec

The dielectric constant of BaTi${\mathrm{O}}_{3}$ single crystals in the region above the 120\ifmmode^\circ\else\textdegree\fi{}C Curie point has been measured at several frequencies in the range from 1 kc/sec to 2000 Mc/sec. In addition, the $B$ coefficient in Devonshire's equation for the free energy has been studied at 500 Mc/sec. It is shown that the crystal is completely clamped with respect to the measuring field at 500 Mc/sec so that the coefficient of the ${P}^{4}$ term in Devonshire's equation is positive and agrees with the expected theoretical result of ${{B}_{F}}^{C}=2.23\ifmmode\times\else\texttimes\fi{}{10}^{\ensuremath{-}13}$ cgs unit.
Analysis of the Kinetic Mechanism of Haloalkane Conjugation by Mammalian θ-Class Glutathione Transferases

Glutathione (GSH) transferases (GSTs) catalyze the conjugation of small haloalkanes with GSH. In the case of dihalomethanes and vic-1,2-dihaloalkanes, the reaction leads to the formation of genotoxic GSH conjugates. A generally established feature of the reaction of the mammalian theta-class GSTs, which preferentially catalyze these reactions, is the lack of saturability of the rate with regard to the substrate concentration. However, the bacterial GST DM11 catalyzes the same reactions with a relatively low K(m). Recently, DM11 has been shown to exhibit burst kinetics, with a rate-determining k(off) rate for product (Stourman et al. (2003) Biochemistry 42, 11048-11056). We examined rat GST 5-5 and human GST T1-1 and did not detect any burst kinetics in the conjugation of C(2)H(5)Cl, CH(2)Br(2), or CH(2)Cl(2), distinguishing these enzymes from GST DM11. The kinetic results were fit to a minimal mechanism in which the rate-limiting step is halide displacement. The differences in the steady state kinetics of conjugations catalyzed by bacterial GST DM11 and the mammalian GSTs 5-5 and T1-1 are concluded to be the result of differences in the rate-limiting steps and not to inherent enzyme affinity for the haloalkanes. The results may be interpreted in the context of a model in which the halide order affects the rate of carbon-halogen bond cleavage of all such reactions catalyzed by the GSTs. With GST DM11, the halide order is manifested in the K(m) parameter but not k(cat). With mammalian GSTs, the high K(m) is difficult to estimate. With all of the GSTs, the halide order is seen in the enzyme efficiency, k(cat)/K(m), with C-Br cleavage approximately 10-fold faster than C-Cl cleavage. The ratio k(cat)/K(m) is the most relevant parameter for issues of risk assessment.
Welfare reform and high school dropout patterns for children

Abstract This study examines the impact of parental work and continuity of welfare receipt on the drop out rates of high school students in families in poverty. The risk of dropping out from school is examined in light of potential effects on subsequent social and economic well-being. The data indicate that drop out rates have increased over the past decade for children on public assistance, but that consistency in parental employment and transitions off welfare are associated with lower rates of dropping out of high school. The results are discussed in terms of their implications for preventative strategies that might be employed by child welfare and school social workers.
Exactly solvable unitary matrix models: Multicritical potentials and correlations

Abstract Multicritical potentials are given for exactly solvable unitary matrix models. These correspond to equations for the square root of the specific heat that are related to the conserved densities of the modified Korteweg-de Vries equation. Correlations are studied, and expressions are obtained for correlations including the torus contribution. These correlations agree in the planar limit with those in hermitian matrix models. Analytical and numerical arguments are given for the positivity of the fixed area partition function coefficients, for k = 1, 2 and 3.
Issues of practical realization of a quantum dot register for quantum computing

We present a quantum dot structure fabricated by the lithographic positioning, which can be used as a prototype of the quantum dot register for quantum computing. Using simple model calculations we show that parameters of our quantum dot structure are very close to the ones required for two possible embodiments of a quantum computer. Results of numerical simulation of the quantum dot register, as well as discussion of materials and technological issues of fabrication of quantum logic gates are also presented.
Towards a Model of Fault Tolerance Technique Selection in Static and Dynamic Agent-Based Inter-Organizational Workflow Management Systems

Research in workflow management systems design references the mobile agent computing paradigm where agents have been shown to increase the total capacity of a workflow system through the decoupling of execution management from a statically designated workflow engine, although coordinating fault tolerance mechanisms has been shown to be a downside due to increased overall execution times. To address this issue, we develop a model for comparing the effects of two fault tolerance techniques: local and remote checkpointing. The model enables an examination of fault tolerance coordination impacts on execution time while concomitantly taking into account the dynamic nature of a workflow environment. A proposed use for the model includes providing for selecting and configuring agent-based fault tolerance approaches based on changes in environmental variables - an approach that allows the owners of a workflow management system to reap the scaling efficiency benefits of the mobile agent paradigm without being forced to make trade-offs in execution performance.
Somatotopy of the motor cortex after long-term spinal cord injury or amputation

Certain brain-computer interface (BCI) methods use intrinsic signals from the motor cortex to control neuroprosthetic devices. The organization of the motor pathways in those populations likely to use neuroprosthetic devices, therefore, needs to be determined; there is evidence that following disease or injury the representation of the body in the motor cortex may change. In this study, functional MRI measures of somatotopy following spinal cord injury (SCI) showed evidence of changes in limb representations in the motor cortex. Subjects with chronic SCI had unusual cortical patterns of activity when attempting to move limbs below their injury; amputees showed a more normal somatotopy. The functional reorganization may affect optimal implanted electrode placements for invasive BCI methods for these different populations.
Trichoderma species form endophytic associations within Theobroma cacao trichomes.

Trichoderma species are usually considered soil organisms that colonize plant roots, sometimes forming a symbiotic relationship. Recent studies demonstrate that Trichoderma species are also capable of colonizing the above ground tissues of Theobroma cacao (cacao) in what has been characterized as an endophytic relationship. Trichoderma species can be re-isolated from surface sterilized cacao stem tissue, including the bark and xylem, the apical meristem, and to a lesser degree from leaves. SEM analysis of cacao stems colonized by strains of four Trichoderma species (Trichoderma ovalisporum-DIS 70a, Trichoderma hamatum-DIS 219b, Trichoderma koningiopsis-DIS 172ai, or Trichoderma harzianum-DIS 219f) showed a preference for surface colonization of glandular trichomes versus non-glandular trichomes. The Trichoderma strains colonized the glandular trichome tips and formed swellings resembling appresoria. Hyphae were observed emerging from the glandular trichomes on surface sterilized stems from cacao seedlings that had been inoculated with each of the four Trichoderma strains. Fungal hyphae were observed under the microscope emerging from the trichomes as soon as 6 h after their isolation from surface sterilized cacao seedling stems. Hyphae were also observed, in some cases, emerging from stalk cells opposite the trichome head. Repeated single trichome/hyphae isolations verified that the emerging hyphae were the Trichoderma strains with which the cacao seedlings had been inoculated. Strains of four Trichoderma species were able to enter glandular trichomes during the colonization of cacao stems where they survived surface sterilization and could be re-isolated. The penetration of cacao trichomes may provide the entry point for Trichoderma species into the cacao stem allowing systemic colonization of this tissue.
Increasing Adherence to Substance Abuse Aftercare Group Therapy

Abstract Adherence to aftercare therapy in substance abuse treatment is associated with improved outcomes. Although previous research has established that adherence contracts and orientation to aftercare are an effective method of increasing aftercare attendance, participation levels are often low. We examined whether feedback and prompts are an effective means of further increasing adherence to substance abuse aftercare group therapy beyond that found when orientation and adherence contracts are completed. We randomly assigned 41 substance dependent individuals completing inpatient or intensive outpatient treatment to receive either attendance feedback and prompts to attend aftercare, or no feedback and no prompts. Participants who received the feedback and prompts were more likely to begin aftercare, and to attended more weekly aftercare groups, and they were less likely to be readmitted to the hospital. The clinical utility of prompts and feedback are discussed.
Semi-Automatic Prediction of Landmarks on Human Models in Varying Poses

We present an algorithm to predict landmarks on 3D human scans in varying poses. Our method is based on learning bending-invariant landmark properties. We also learn the spatial relationships between pairs of landmarks using canonical forms. The information is modeled by a Markov network, where each node of the network corresponds to a landmark position and where each edge of the network represents the spatial relationship between a pair of landmarks. We perform probabilistic inference over the Markov network to predict the landmark locations on human body scans in varying poses. We evaluated the algorithm on 200 models with different shapes and poses. The results show that most landmarks are predicted well.
Storage Management in Virtualized Cloud Environment

With Cloud Computing gaining tremendous importance in the recent past, understanding low-level implications of the cloud infrastructure becomes necessary. One of the key technologies deployed in large Cloud infrastructures namely the Amazon EC2 for providing isolation and separate protection domains for multiple clients is virtualization. Therefore, identifying the performance bottlenecks in a virtualized setup and understanding the implications of workload combinations and resource configurations on the overall I/O performance helps both the cloud providers in managing their infrastructure efficiently and also their customers by means of better performance. In this paper we present the measurement results of detailed experiments conducted on a virtualized setup focusing on the storage I/O performance. We categorize our experimental evaluation into four components, each of which presenting some significant factors that affect storage I/O performance. Our experimental results can be useful for cloud application developers to tune their applications for better I/O performance and for the cloud service providers to make more effective decisions on resource provisioning and workload scheduling.
Pro-inflammatory Cytokines Increase Reactive Oxygen Species through Mitochondria and NADPH Oxidase in Cultured RPE Cells

Reactive oxygen species (ROS) generated during inflammation are believed to play critical roles in various ocular diseases. However, the underlying mechanisms remain poorly understood. We investigated if pro-inflammatory cytokines, tumor necrosis factor (TNF)-alpha, interleukin-1 beta (IL-1 beta), and interferon-gamma (IFN-gamma), induce ROS in human retinal pigment epithelial (RPE) cells. TNF-alpha, IL-1 beta and IFN-gamma increased both intracellular and extracellular ROS production in a time- and dose-dependent manner. Thenoyltrifluoroacetone (TTFA), an inhibitor of mitochondrial respiratory chain, blocked TNF-alpha- and IFN-gamma-, but not IL-1 beta-induced ROS, whereas other two mitochondrial respiratory chain inhibitors, rotenone and antimycin A, had no effect. NADPH oxidase inhibitor (diphenylene iodinium) abolished the ROS production induced by IL-1 beta or IFN-gamma, but not by TNF-alpha, whereas 6-aminonicotinamide (6AN), an inhibitor of the hexose monophosphate shunt (HMS), had no significant effects on the ROS induced by all three cytokines. ROS scavengers, pyrrolidinedithiocarbamate (PDTC) and N-acetyl-cysteine (NAC), reduced the levels of ROS induced by TNF-alpha, IL-1 beta and IFN-gamma (P<0.05). Collectively, these results demonstrate that TNF-alpha, IL-1 beta and IFN-gamma increase mitochondrial- and NADPH oxidase-generated ROS in human RPE cells.
Performance analysis of multilevel bus networks for hierarchical multiprocessors

A multiple bus system provides more bandwidth and a high degree of fault tolerance than a single bus system. But such a system becomes very expensive for a large number of processors and memory modules, due to the requirement of too many connections (switches). Lang (1983) proposed a different bus-based system, known as the partial multiple bus system, which requires a lower number of connections than a multiple bus system, but with a slight degradation in system performance. This paper presents a new type of bus-based system, called the multilevel bus system. Such a bus architecture can be used to design hierarchical multiprocessors. This bus-based system requires significantly less connections than multiple and partial multiple bus systems. This system is very cost-effective, as compared to multiple and partial multiple bus systems, when there exists some locality in the computations. Analytical and simulation models have been developed to determine the performance of both synchronous and asynchronous multilevel bus systems. The results obtained from the analysis show that a multilevel bus system performs fairly close to other bus-based systems for the hierarchical reference (HR) model. In the HR model, a processor accesses its nearest memory modules more frequently than other memory modules. >
Cumulating Knowledge on Crisis Escalation

A Study of Crisis, Michael Brecher, Jonathan Wilkenfeld (Ann Arbor: University of Michigan Press, 1997). 1,064 pp., cloth (ISBN: 0-472-10806-9), $115.00. Book reviewed: A Study of Crisis , Michael Brecher and Jonathan Wilkenfeld
Design of semi-degradable hydrogels based on poly(vinyl alcohol) and poly(lactic-co-glycolic acid) for cartilage tissue engineering

Articular cartilage damage is a persistent challenge in biomaterials and tissue engineering. Poly(vinyl alcohol) (PVA) hydrogels have shown promise as implants, but their lack of integration with surrounding cartilage prevents their utility. We sought to combine the advantages of PVA hydrogels with poly(lactic-co-glycolic acid) (PLGA) scaffolds, which have been successful in facilitating the integration of neocartilage with surrounding tissue. Through a novel double-emulsion technique, PLGA microparticles and a high level of porosity were simultaneously incorporated into PVA hydrogels. The porosity, average pore size and swelling properties of the hydrogels were controlled by varying initial processing parameters, such as the relative amounts of PLGA and solvent. Average pore sizes were in the ranged 50-100 µm. The PLGA microparticles degraded within the hydrogels over time in aqueous conditions, resulting in increases in porosity and pore size. After 4 weeks in cell culture, immature cartilage tissue filled many of the pores of the hydrogels that initially contained PLGA, and proteoglycan production was proportional to the amount of PLGA. In contrast, there was little cell attachment and no proteoglycan production in control hydrogels without PLGA. The compressive moduli of the hydrogels were similar to that of healthy cartilage and increased over time from 0.05-0.1 to 0.3-0.7 MPa. The generation of a hybrid cartilage-hydrogel construct using this technique may finally allow the integration of PVA hydrogels with surrounding cartilage.
Approximation methods and spatial interpolation in distributed control systems

We propose an approximation method to solve large-scale optimal control problems for spatially distributed systems. The finite-section method is employed to construct finite-dimensional approximations to the large-scale optimal control problem. Then, we study the limit behavior of the approximation method and show that the solution of the approximate problems converge strongly to the solution of the large-scale problem. These techniques are applied to design finite-dimensional local optimal controllers. Finally, a spatial interpolation method is proposed that can patch all locally designed controllers to construct a parameterized family of stabilizing controller for the spatially distributed system. Furthermore, we characterize the class of stabilizing controllers which have finite supports.
Leveraging COUNT Information in Sampling Hidden Databases

A large number of online databases are hidden behind form-like interfaces which allow users to execute search queries by specifying selection conditions in the interface. Most of these interfaces return restricted answers (e.g., only top-k of the selected tuples), while many of them also accompany each answer with the COUNT of the selected tuples. In this paper, we propose techniques which leverage the COUNT information to ef?ciently acquire unbiased samples of the hidden database. We also discuss variants for interfaces which do not provide COUNTinformation. We conduct extensive experiments to illustrate the ef?ciency and accuracy of our techniques.
Assessing the efficiencies of low and high volume methods of applying pesticides to tobacco.

Low volume carbendazim sprays (25–100 litre/ha) applied with a knapsack mistblower fitted with twin nozzles or a mesh diffuser were compared with high volume sprays (760 litre/ha) from three pairs of ‘Spraying Systems’ Y6 nozzles on the vertical boom of a knapsack pressure sprayer. The carbendazim concentration and total amount deposited were measured by thin-layer chromatography and bioassay. The twin nozzles, which directed two spray streams 50° apart, deposited most fungicide on the plants using 100 litre/ha, and in two experiments 76 and 80% of theoretical amounts applied per plant were detected in or on the leaves. At 25 litre/ha, the distribution was less uniform and the deposit efficiency was 74%. The mesh diffuser at 100 litre/ha was less efficient; where the spray was directed between and parallel to the rows of tobacco the deposits were 26 and 42% of the total carbendazim applied, whereas directing the spray at an angle of about 45° towards the rows of tobacco increased the deposit to 57%. Sprays applied at a pressure of 410 kPa (4.1 bar) from Y6 nozzles deposited only 16% of the active ingredient onto the leaves. Better control of powdery mildew caused by Erysiphe cichoracearum was obtained with dinocap using the mesh diffuser than with either the Y6 nozzles or with dusts from a motorised duster.
Neutron Stimulated Emission Computed Tomography (NSECT) for Early Detection of Breast Cancer

Neutron stimulated emission computed tomography (NSECT) is being developed as a non-invasive spectroscopic technique to determine element concentrations in the human body. We have implemented an NSECT system that uses a beam of high-energy neutrons to identify element concentrations in tissue and create 2-dimensional maps of elemental distribution through a single non-invasive tomographic scan. Neutrons scatter inelastically with atomic nuclei in tissue, causing them to emit characteristic gamma photons. These gamma photons are detected and identified using an energy-sensitive gamma detector. By measuring the energy and number of emitted gamma photons, the system can determine the elemental composition of the target tissue. NSECT has the advantage of being able to detect breast cancer at very early stages compared to anatomic screening techniques, as it detects changes in trace element concentrations in the breast, which usually occur before anatomical features such as tumors and micro-calcifications appear. The tomographic scanning system eliminates the need for breast compression and patient disrobing. The system design can be made portable by using a commercially available portable neutron source with a gamma detector. From our preliminary results, NSECT shows significant promise in early diagnosis of breast cancer. It has the potential to evolve into an easily accessible screening modality and diagnostic technique for breast cancer, which can detect and identify malignant tissue in the breast and generate a two-dimensional image through a single non-invasive tomographic scan. Patient dose levels from NSECT are comparable to those of screening mammography. Efforts are under way to achieve the micro-gram sensitivity required for in-vivo trace element detection in the breast at the lowest possible patient dose levels. Our final goal is to implement a portable, low-dose tomographic screening system for breast cancer which does not require breast compression or invasive biopsies.
A software framework for integrated sensor network applications

Sensor networks have received wide attention in recent years for their revolutionary impact in numerous fields. To harness their full potential, researchers are beginning to build end-to-end solutions that integrate heterogeneous sensor deployments with traditional networks. While such efforts will bring true value to the use of sensor networks, there are several challenges that need to be kept in perspective. This paper highlights some of the key challenges, and presents a system software methodology to meet the difficult demands of development, deployment and long term management of sensor network systems.
What Can the Spinal Cord Teach Us about Learning and Memory

The work of recent decades has shown that the nervous system changes continually throughout life. Activity-dependent central nervous system (CNS) plasticity has many different mechanisms and involves essentially every region, from the cortex to the spinal cord. This new knowledge radically changes the challenge of explaining learning and memory and greatly increases the relevance of the spinal cord. The challenge is now to explain how continual and ubiquitous plasticity accounts for the initial acquisition and subsequent stability of many different learned behaviors. The spinal cord has a key role because it is the final common pathway for all behavior and is a site of substantial plasticity. Furthermore, because it is simple, accessible, distant from the rest of the CNS, and directly connected to behavior, the spinal cord is uniquely suited for identifying sites and mechanisms of plasticity and for determining how they account for behavioral change. Experimental models based on spinal cord reflexes facilitate study of the gradual plasticity that makes possible most rapid learning phenomena. These models reveal principles and generate concepts that are likely to apply to learning and memory throughout the CNS. In addition, they offer new approaches to guiding activity-dependent plasticity so as to restore functions lost to injury or disease.