cssi/SciSciGPT-SciSciNet huggingface dataset:
Repeated nicotine exposure during adolescence alters reward-related learning in male and female rats.

Abstract Rationale Repeated nicotine exposure causes neuroadaptations in limbic cortico-striatal circuits involved in learning and motivation. Such alterations are relevant to addiction because they are suggested to mediate the ability of smoking-associated stimuli to control behavior and to enhance nicotine-seeking and -taking behaviors. Female smokers report higher cue reactivity relative to their male counter parts, yet little is known about putative gender-specific effects of adolescent nicotine exposure on reward-related learning. Prior repeated nicotine exposure in adult male rats enhances Pavlovian approach behavior and conditioned reinforcement. Objective Given that smoking is typically initiated during adolescence, here we assessed the extent to which adolescent nicotine exposure impacts Pavlovian approach and conditioned reinforcement in male and female rats. Methods Rats were injected with nicotine on postnatal days 31–45 prior to training on Pavlovian approach behavior starting on day 51. They were trained to associate a conditioned stimulus (CS), illumination of a magazine light, and tone, with an unconditioned stimulus (US), the delivery of water, for 10-daily sessions, and then were tested on the acquisition of responding with conditioned reinforcement. Results Adolescent nicotine exposure selectively increased approach to the magazine during the CS in males but decreased approach to the magazine during the CS in female rats. Vehicle-exposed female rats, however, showed greater magazine approach during the CS than did male control rats. Prior nicotine exposure also enhanced conditioned reinforcement in both male and female rats. Conclusions Repeated exposure to nicotine during adolescence had opposite effects on Pavlovian approach behavior in male and female rats but enhanced acquisition of a new response with conditioned reinforcement. Novel information on how nicotine exposure influences reward-related learning during adolescence may increase our understanding of neurobiological mechanisms involved in the initiation of smoking behavior.
Modified Equivalent Gain Analysis of Non-linear Systems with Gaussian Noise

In this paper a modified equivalent gain expression is determined for a class of non-linear transfer characteristics subjected to Gaussian random disturbances. The non-linearites considered are of the non-memory saturating piecewise-linear type, which are important both in their own right and because they can be used to approximate, to any desired degree of accuracy, many other non-linear transfer characteristics. This equivalent gain expression is then used in a frequency domain analysis to predict the amplitude and frequency of self-sustained oscillations in systems containing these non-linearities. In an example, a system containing a quantizer subjected to Gaussian noise is analysed by this technique. The results are found to agree closely with those of a digital computer simulation of the system.
Modeling suspended sediment distribution patterns of the Amazon River using MODIS data

Abstract Patterns of surface sediment concentration distribution in rivers are significant for understanding fluvial morphodynamics and environmental characteristics of the rivers and their floodplains. In the case of the Amazon Basin, complexity in sediment pattern distribution is affected by the anabranching channel pattern of the Amazon River, inputs from tributaries (some of which are among the largest rivers on Earth) and the existence of huge and complex floodplains. In this paper, patterns of surface sediment distribution are modeled based on Moderate Resolution Imaging Spectroradiometer (MODIS) data over the Amazon River by estimating surface sediment concentrations. Specifically, we aim to 1) detect the regional and seasonal variability of surface sediment in the main channel, 2) observe the influence of tributaries into the main system, 3) identify channel-floodplain interactions, and 4) investigate the internal variability of surface sediment along the main channel system. Field surface sediment concentration data from three gauging stations representing the upstream, midstream, and downstream sections of the Amazon River between 2000 and 2010 were used to calibrate 1328 MODIS daily surface reflectance images. Robust empirical models were derived between field surface sediment concentration and surface reflectance data from each station (0.79
Well Completion Audits to Evaluate Gravel Packing Procedures

Data collected during gravel packed completions may be analyzed to evaluate the impact of specific completion practices on well performance. Operations where gathering data is critical are: (1) during the initial flow and perforation cleanup after underbalanced perforating, (2) during prescribed injection tests prior to gravel packing, (3) during periods in which fluid is being injected into the formation (pre-packing perforations, fluid loss after perforating, fluid loss after gravel packing), and (4) during stabilized flow after the well is brought on line. This data can be used to calculate an approximate value for kh (md.ft.) and an instantaneous completion efficiency at different stages of the completion. By comparing these instantaneous completion efficiencies, the damage contribution of certain operations and the damage prevention aspects of other operations may be quantified. This methodology should provide a valuable resource to those pursuing continuous improvement in well completion operations, particularly those involved in sand control.
Purification and properties of a factor from insect hemolymph that promotes multicellular vesicle formation in vitro

A vesicle promoting factor (VPF) in an insect cell line IAL-TND1 was partially purified from larval hemolymph of the cabbage looper, Trichoplusia ni Hubner. The polypeptide had a molecular weight estimated to be between 20.5 kD and 37.5 kD by gel permeation, 22.5 kD by the Ferguson plot on nondenaturing polyacrylamide gel electrophoresis, and 16.88 kD on sodium dodecyl sulfate PAGE. VPF fractions were isolated from hemolymph by gel permeation on Fractogel® and were either subjected to chromatofocusing or preparative isoelectric focusing. After the gel permeation step, the VPF polypeptide was highly unstable during the separation and storage. The two active fractions from the isoelectric separations had isoelectric points of 6.21 and 6.36 and had specific activities of 34 and 32 vesicles/μg protein per test culture chamber. The percentage of total larval equivalent hemolymph proteins found in these fractions was less than 1%. Chromatofocusing technique also yielded an active fraction containing a single band on nondissociating electrophoresis that had VPF activity. This band had an isoelectric point of 6.60 but had a lower specific activity of three vesicles/μg protein in the VPF cell bioassay.
The Departure Status of Youth from Residential Group Care: Implications for Aftercare

Youth departing from out-of-home care settings face numerous challenges as they adapt to new settings or return to placements that have been unsuccessful in the past. Although several thousand youth face this transition annually, little is known about their specific needs and risks at departure. To better identify needs and risks, we evaluated the discharge data of 640 youth served in a residential group care setting by addressing the following questions: (a) to what settings do youth depart following a stay in residential group care, (b) what are the demographic, family, educational, behavioral, and departure characteristics of youth at departure, and (c) do these characteristics differ for youth departing to different levels of restrictiveness? Results indicate significant differences on youth characteristics based on levels of restrictiveness at departure placement. As one might expect, youth departing to more restrictive placements presented a broad host of challenges across domains, while those departing to less restrictive settings demonstrated fewer needs and departed with greater educational and behavioral gains. Results provide support for the development and planning of targeted aftercare programs designed to promote the short and long term functioning of youth served in out-of-home care.
Absence of direct repeats flanking transposons resulting from intramolecular transposition

Tn2660 is an ampicillin-resistance-conferring transposon with a high degree of homology for the transposon Tn3. The nucleotide sequences flanking the termini of Tn2660 have been determined on plasmids inferred to have resulted from both inter- and intramolecular transposition of Tn2660. In all cases, transposition of Tn2660, as of Tn3, creates 5-bp flanking direct repeats, except following intramolecular transposition resulting from trans ligation. In this case, in R6K replicons, the nucleotide sequence between the two Tn2660 elements is stably inverted from the normal orientation, and 5-bp direct repeats do not flank each transposon, but instead flank opposite ends of the two transposon copies.
Pseudonondiffracting slitlike beam and its analogy to the pseudonondispersing pulse

A new nonspreading beam is proposed for the case in which diffraction occurs only in one transverse coordinate. The beam has the shape of a pulse in one dimension and is constant in the other (slitlike shape). The intensity of the pulse’s peak remains almost constant along a finite interval on the propagation axis. The proposed beam is analyzed and demonstrated experimentally. The analogy between this beam and the temporal pulse in a dispersive medium is discussed.
Introduction to the IBM optimization subroutine library

This essay introduces the IBM Optimization Subroutine Library (OSL) and seven OSL-related papers that appear in this issue. Developed as a result of a partnership between several IBM research and development groups, OSL provides a suite of tools for manipulating the models and solving the resulting minimization and maximization problems of mathematical optimization. The problems that OSL addresses include: linear, quadratic, mixed-integer, and pure network programming problems. OSL includes solvers based on the classical simplex method and on newer interior point methods. Because a user-supplied driver program coordinates the problem solution, and because of the “mix and match” philosophy of OSL, a user may, within rather wide limits, individually tailor a technique to solve a particular problem. We conclude that OSL is something new in optimization software.
Preparation, molecular structure and electronic structure of the rhombic, six-coordinate niobium(IV) complex NbCl2(ButC(O)CHC(O)But)2

Abstract The compound trans-NbCl2(dpm)2, Hdpm = 2,2,6,6-tetramethylheptane-3,5-dione, has been prepared and the molecular structure determined in each of two crystalline polymorphs by X-ray diffraction. The visible spectrum and the EPR spectrum have been measured and a Fenske—Hall calculation performed. The combined results give a reasonable and internally consistent picture of the electronic structure of the molecule. The HOMO is a b3g-orbital (predominantly dyz), while the two lowest-lying unoccupied orbitals (ca 16,000 cm−1 higher) are b2g(sim; dxz) and ag(sim; dx2−y2) orbitals, all in the D2h-symmetry. The b3g → b2g and b3g → ag transitions are observed at 588.4 and 626.7 nm. The EPR spectrum in solution is a decet; the measured value of is 1.930 and is 149 G. For the crystalline polymorph 1 the crystal data are: orthorhombic (P212121), a = 13.649(3) A, b = 18.166(4) A, c = 11.425(4) A, V = 2833(2) A3 and Z = 4. Polymorph 2 is monoclinic (P21/n) with a = 12.288(5) A, b = 9.226(4) A, c = 12.545(4) A, β = 94.24(3)°, V = 1418(2) A3 and Z = 2. The molecule in 2 is centrosymmetric with virtual D2h-symmetry. In 1 there are distortions in the chelate plane postulated to be due to packing forces. The two forms have comparable averaged values of interatomic dimensions.
Model Minority Demystified -- Emotional Costs of Multiple Victimizations in the Lives of Women of Japanese Descent

Summary This population-based study investigated the prevalence of domestic violence and other types of interpersonal victimization among a random sample of women of Japanese descent (immigrants from Japan and Japanese Americans) in Los Angeles. This study found a high prevalence of domestic violence, as well as other types of violence, perpetrated by non-intimates. Differences by country of birth were found in some, but not all, types of victimization; a larger proportion of Japan-born respondents reported experiencing contact and no-contact sexual violence perpetrated by non-intimates and witnessing their fathers' violence against their mothers. The severity of domestic violence experienced during the respondents' lifetimes was significantly associated with a higher degree of psychological distress. Findings question the commonly presumed image of the model minority and call for increased efforts to assess the history of domestic violence and other types of interpersonal victimization when working with ...
Fabrication and Cyclic Behavior of Highly Ductile Superelastic Shape Memory Composites

AbstractTo address the problem of steel corrosion, fiber-reinforced polymer (FRP) bars are often used as reinforcement in concrete structures. However, conventional FRP bars are characterized by linear elastic behavior that limits their efficacy in seismic structural applications. This paper investigates the fabrication and cyclic behavior of a relatively new class of composite material known as SMA-FRP that could be used as seismic reinforcement for concrete structures. The new composite comprises a high elongation resin matrix, embedded with superelastic NiTi shape memory alloy (SMA) wires as primary reinforcement. The SMA wires are used either with or without the addition of conventional fibers. The hysteretic nonlinear pseudoelastic behavior of SMA provides the new composite with features that conventional FRP lacks, such as ductility and energy dissipation capability. The experimental program carried out in this study starts with the training of SMA wires, and the investigation of the hysteretic beha...
Is there an established role for immunotherapy for any of our surgical cancers

Despite major advances in the management of the patient and in surgical and radiation therapy, cancer deaths continue to occur secondary to widespread metastases. Therefore, systemic treatments in the form of chemotherapy, hormonal therapy, and immunotherapy are constantly being investigated, both as adjuvant to the local therapeutic modalities, as well as therapeutically for unresectable metastases. While the first two systemic modalities have established themselves in cancer management, immunotherapy has been lagging behind for several reasons.
Potentially lethal complications of central venous catheter placement

Abstract Background: Placement of central venous catheters, although often considered to be a relatively safe and "junior"-level procedure, may be associated with life-threatening complications. Methods: A recent surgical death associated with placement of a central venous catheter at this Institution led to submission of a questionnaire to pediatric surgeons referenced through the American Pediatric Surgical Association directory regarding knowledge of similar incidents and information regarding catheter placement—related complications. Results: Results to this response, although anecdotal, provided data regarding complications of an acute nature, which fell into the categories of pneumothorax, hydrothorax, cardiac tamponade, and hemothorax. Of 10 children with cardiac tamponade, 7 were infants, and most complications were associated with needle stick for access, with symptoms developing within minutes up to 12 hours after the procedure. Drainage of the tamponade was performed by aspiration alone in 3 cases; surgical drainage in 6 children resulted in survival in 9 of the 10 patients. Hemothorax was described in 19 patients and appeared to be more common in children in the 1- to 6-year age group, usually associated with percutaneous access techniques. Thoracotomy for hemothorax was performed in 16 children with 11 survivors. Vascular injury to subclavian artery, vein, or superior vena caval were noted in most at operation. Conclusions: Although data included in this review are entirely anecdotal and not subject to scientific scrutiny or analysis, certain conclusions appear evident. Inherent risks of central venous catheters are intrinsic and should be discussed with the family in obtaining preoperative consent, including life-threatening risks that may necessitate urgent surgical intervention (by thoracotomy or other means). Certain technical aspects of the procedure should be rigidly followed with an experienced surgeon in attendance throughout the procedure. Rapid evaluation should be performed for any unexplained problems that occur in the operating theatre or during the early postoperative period. J Pediatr Surg 35:709-713. Copyright © 2000 by W.B. Saunders Company.
Endoscopic clips prevent displacement of intestinal feeding tubes: a long-term follow-up study.

Background Displacement of jejunal feeding tubes is a major problem in enteral feeding. Although endoscopic clips have been used to prevent migration of the tube during placement, the long-term effect of the clips on tube displacement is unknown. Objectives The purpose of this study was to examine the long-term effect of endoscopic clips on preventing displacement of the jejunal feeding tube. Design A retrospective study. Setting A single tertiary medical center. Main outcome measurements The success rate of the procedure and the functional duration of the feeding tube. Results About 93% of patients had a percutaneous endoscopic gastrostomy jejunal (PEGJ) tube successfully placed with use of endoscopic clips. About 7% had tube migration and repeat procedures were successful. The mean functional duration of the tube was 55 days. Limitations Retrospective, single-center. Conclusions Use of endoscopic clips can prevent migration during placement of the feeding tube and can also reduce tube displacement in the long term.
Experimental Study of Steady Quasi-Cone-Jet Electrostatic Sprays of Biobutanol for Engine Applications

AbstractButanol produced from agricultural sources is emerging as a potentially renewable biofuel for use in engine applications. In this work, butanol electrostatic sprays were established within a narrow region of low flow rates. Spray phenomenology was investigated through high-speed visualization for the low flow rate conditions in the vicinity of the lowest voltage for which electrosprays (e-sprays) could be sustained. Spray structure was studied through droplet size and velocity measurements for a combination of conditions, performed by using phase Doppler anemometry. Combined with high-speed spray visualization, these measurements revealed a stable e-spray operation with narrow droplet size and velocity distributions; i.e., spray behavior was close to monodisperse. A similarity analysis was performed to develop an empirical expression correlating appropriately dimensionless average diameter, flow rate, and applied voltage.
The adversity of Brazilian drought

Drought-stricken NE Brazil is studied in the context of four regional units: the semiarid lowlands of the interior sertao, which have the maximum precipitation fluctuations; the well-watered Cariri valley, which experiences harvest shortages during abnormally dry years; the coastal fringe, which suffers during years of widespread drought; and the highlands of Baturite, where dry spells are noticed only through an influx of migrants from low-lying and drought-stricken areas. Adjustment to drought is, in general, low; it depends on the degree of drought awareness, which is also quite low. Affluent individuals are more inclined to make adjustments to droughts, although the likelihood of their being affected is less than among poor individuals. Middleclass individuals are more inclined to react to threats of an impending drought than to act under actual drought conditions. If age is taken into consideration, middle-aged individuals show greater awareness of drought conditions and a higher propensity to making adjustments than aged or youthful populations. Women are less inclined to make adjustments than men, and married people less than singles. Large families, probably compelled by the constraints, are especially prone to undertake changes in living conditions when a drought strikes. In general, the choices provided by economic feasibility, the possibilities of mitigating drought effects through technological know-how, and the social input of marriage and family size are very important parameters in shaping the character of the adjustments to drought.
Work in progress — Retention and FIGS: Institutional versus engineering major efficacy

In an attempt to retain students, institutions have implemented programs focused on “the first year experience”. Many institutions link their first-year programs to specific disciplines, calling these programs freshmen interest groups or “FIGs.” In this research we explore the extent to which this FIG model, found in other research to be effective for improving general institutional retention, can be extended to improve major specific retention in Environmental Resources Engineering (ERE) at Humboldt State University. Analysis from institutional and departmental sources on three cohorts of freshmen ERE majors in FIG (n=29) and Non-FIG (n=15) groups, as well as other non-ERE FIGS groups indicates that ERE freshmen enrolled in FIGs continued to their sophomore year at HSU at the same average rate as students in other FIGs (76%) and at a significantly higher rate than all Non-FIG freshmen (72%). However, FIG participation did not affect retention in the engineering major itself. Our study suggests that the FIG model best addresses the instabilities of transition into college and that major retention in science and engineering is a more complex phenomenon that the current FIGs model does not address. Data for two additional cohorts of freshmen (n=65) will be added to this analysis and the combined results will be reported at the conference.
Novel hollow fiber immobilization techniques for whole cells and advanced bioreactors

A novel microporous hollow fiber membrane-based immobilization technique for whole cells has been developed. Yeast cells (Saccharomyces cerevisiae) were grown on chopped hydrophobic microporous hollow fibers as well as on hydrophilic hollow fibers. This immobilization support was used to carry out fermentation in a tubular bioreactor. Air was passed from time to time to facilitate cell growth. The microbial culture reached a very high cell density level of around 1010/mL of fiber lumen volume. An ethanol concentration of 45 g/L and productivity of 41 g/L-h were obtained with an initial glucose concentration of 100 g/L. The present technique does not have the shortcomings of conventional immobilization methods.
Evaluation of a focused library of N-aryl L-homoserine lactones reveals a new set of potent quorum sensing modulators

A focused library of N-aryl l-homoserine lactones was designed around known lactone leads and evaluated for antagonistic and agonistic activity against quorum-sensing receptors in Agrobacterium tumefaciens, Pseudomonas aeruginosa, and Vibrio fischeri. Several compounds were identified with significantly heightened activities relative to the lead compounds, and new structure-activity relationships (SARs) were delineated. Notably, 4-substituted N-phenoxyacetyl and 3-substituted N-phenylpropionyl l-homoserine lactones were identified as potent antagonists of TraR and LuxR, respectively.
The mechanism of aldosterone function.

Aldosterone, the secretory product of the zona glomerulosa of the adrenal cortex, stimulates active Na reabsorption across numerous epithelial tissues specialized to carry out transcellular transport of Na. The target tissues most extensively studied for this most potent mineralocorticoid are the mammalian kidney and the urinary bladder of the toad, Bufo marinus. Other known target tissues are listed in Table 1. In this review we will attempt to assess critically information concerning the mechanisms involved in the effect of aldosterone on target tissues. We shall first direct attention to the physiologic effects of the hormone-its action on sodium, potassium and hydrogen ion transport and excretion. This will be followed by an assessment of studies on the ‘receptor’ for aldosterone, a review of the evidence that aldosterone’s action is mediated via RNA and protein synthesis and, finally, a consideration of how the final effects of the hormone on sodium transport might be accomplished.
Synthesis and Characterization of a Ditriflate-Bridged, Diiron(II) Complex with Syn-N-Donor Ligands: [Fe2(μ-OTf)2(PIC2DET)2](BARF)2

The synthesis and characterization of the diiron(II) complex [Fe(2)(μ-OTf)(2)-(PIC(2)DET)(2)](BARF)(2) (2), where PIC(2)DET is a 2,3-diethynyltriptycene-linked dipicolinic methyl ester ligand, are described. The dication in 2, contains, [Fe(2)(μ-OTf)(2)(PIC(2)DET)(2)](2+) two symmetry-equivalent iron atoms with octahedral coordination geometries. Each metal ion has a N(2)O(4) atom donor set that includes four atoms from two picolinic ester N,O chelate rings, as well as two oxygen atoms from the bridging trifluoromethanesulfonate groups. The Fe(2)(μ-OTf)(2) core of 2 is stabilized by two PIC(2)DET ligands that bind the two metal ions in a head-to-head fashion, leading to an Fe···Fe distance of 5.173(1)A. Molar conductivity data for 2 are consistent with Fe(2)(μ-OTf)(2)(PIC(2)DET)(2)](2+) retaining its identity in acetone solutions, where it behaves as a 2:1 electrolyte. (1)H NMR spectroscopic, solution (d(6)-acetone) and solid-state magnetic susceptibility data all indicate that the iron atoms of 2 are high-spin (S = 2). A fit of the magnetic data (2 - 300K) to a spin-only isotropic exchange Hamiltonian H = -2JS(1)·S(2) are consistent with weak antiferromagnetic coupling between the two iron atoms with J ~ -0.99(2) cm(-1) and g = 2.10(1).
Burn-up cross sections of 51Cr, 59Fe, 65Zn, 86Rb, 103Ru

Abstract Targets of Cr, Fe, Zn, Rb, and Ru were irradiated in the hydraulic tube of the Oak Ridge HFIR reactor at a neutron flux of 2.6 × 1015 n/cm2sec for 1 day and 20 days. The reactor burn-up cross sections (in barns) of the radioactive product nuclides are: 51Cr, <10; 59Fe, <10; 65Zn, 60±30; 86Rb, <20; 103Ru, <20.
Document clustering, using macro retrieval techniques

Une approche algorithmique est decrite et testee: elle permet, specialement dans les domaines pluridisciplinaires ou de structure floue, de generer un ensemble de documents a partir de references ou de citations. La technique consiste a partir d'un petit sous-ensemble (quelquefois meme d'un seul document) de documents connus comme pertinents, qui forme la base d'un reseau de references structurees et de citations. Des suggestions sont faites en vue d'ameliorer et d'affiner une recherche deja potentiellement bien avancee, grâce a une recherche attentive permettant d'identifier les documents pertinents concernant des sujets interdisciplinaires
Surfactant Replacement Therapy in the Neonate: Beyond Respiratory Distress Syndrome

Surfactant-replacement therapy is a life-saving treatment for preterm infants with respiratory distress syndrome, a disorder characterized by surfactant deficiency. Repletion with exogenous surfactant decreases mortality and thoracic air leaks and is a standard practice in the developed world. In addition to respiratory distress syndrome, other neonatal respiratory disorders are characterized by surfactant deficiency, which may result from decreased synthesis or inactivation. Two of these disorders, meconium aspiration syndrome and bronchopulmonary dysplasia, might also be amenable to surfactant-replacement therapy. This paper discusses the use of surfactant-replacement therapy beyond respiratory distress syndrome and examines the evidence to date.
SiC nanowire vapor–liquid–solid growth using vapor-phase catalyst delivery

A method of growing SiC nanowires (NWs) on 4H–SiC surfaces by in situ vapor-phase catalyst delivery was developed as an alternative to the ex situ deposition of the metal catalyst on the targeted surfaces before the NW chemical vapor deposition (CVD) growth. In the proposed method, sublimation of the catalyst from a metal source placed in the hot zone of the CVD reactor, followed by condensation of the catalyst-rich vapor on bare substrate surface was used to form the catalyst nanoparticles required for the vapor–liquid–solid (VLS) growth of SiC NWs. The NW density was found to gradually decrease downstream from the catalyst source and was influenced by both the gas flow rate and by the catalyst diffusion through the boundary layer above the catalyst source. Formation of poly-Si islands at too low value of the C/Si ratio created preferential nucleation centers for misaligned SiC NWs and NW bushes. The flexibility of controlling the nanoparticle density made this technique suitable for NW growth on horizontal surfaces as well as on patterned SiC substrates, including the vertical sidewalls of SiC mesas.
Change of Erythrocyte Deformability During Fixation in Acetaldehyde

In previous studies in our laboratory (1,2,3), the rheological behavior of erythrocytes hardened in acetaldehyde was compared with that of normal erythrocytes. The loss of deformability in the hardened erythrocytes was demonstrated by a reduction in the degree of centrifugal packing (1), an increase in suspension viscosity with a loss of shear thinning (2), and a decrease of transmission through sieves with small pores (3). The rheological demonstration of flexibility of normal erythrocytes is in agreement with microscopic observations under a variety of conditions (4,5,6,7). The present experiments were performed to study the time course of the loss of deformability as revealed by these rheological tests on human erythrocytes during their fixation in acetaldehyde. The results of these studies may provide a basis for the analysis of rheological behavior of erythrocytes with a partial reduction of deformability in hematological diseases.
AVAILABILITY OF FOOD AND THE POPULATION DYNAMICS OF ARVICOLINE RODENTS

Availability of food may play a number of different dynamical roles in rodent–vegetation systems. Consideration of a suite of rodent–vegetation models, ranging from very simple ones to a model of medium complexity tailored to a specific system (brown lemmings at Point Barrow, Alaska, USA), suggested several general principles. If vegetation grows logistically following an herbivory event (a standard assumption of previously advanced models for herbivore–plant interactions), then almost any biologically reasonable combinations of parameters characterizing rodent–vegetation systems would result in population cycles. We argue, however, that the assumption of logistic growth of the food supply may be appropriate for only a few species, such as moss-eating lemmings. The dynamics of food supply for many arvicoline (microtine) rodents may be better described by a “linear initial regrowth” model, which exhibits globally stable dynamics. If this is so, quantitative interactions with food supply are unlikely to exp...
Get with the Program: The Medium Is Not the Message.

With television having matured as a creative medium in the past few decades, it has taken its rightful place among the subjects scholars study seriously. Professors are now analyzing the meaning and significance of classic shows like Seinfeld, The Simpsons, and The Sopranos with the care and intellectual respect traditionally accorded to literary masterpieces. But some academics still resist the idea that anything of genuine and lasting artistic value can be found on television. This resistance seldom results from empirical study, that is, from actually watching the TV programs other scholars are writing about. Rather, it usually takes the form of a blanket condemnation of television as a medium, a dismissal in principle that relieves the critic of any need to bother with studying individual programs.There is supposedly something different about television as a medium that forever condemns it to mediocrity. Great books may be written; great plays may be staged; I would suppose that eve... Language: en
Mechanical reinforcement of unsaturated polyester by AL2O3 nanoparticles

Abstract Nanometer-sized Al2O3 particles (15 nm average diameter) were used as reinforcements to enhance the fracture toughness of a highly crosslinked, nominally brittle, thermosetting-unsaturated polyester resin. It was observed that the addition of untreated, as-received Al2O3 particles does not result in enhanced fracture toughness. Instead, the fracture toughness decreases by 15% as the volume fraction of the particles is increased from 0% to 4.5%. Similar degradation in fracture toughness was observed for reinforcement by 1- and 35-μm Al2O3 particles. The lack of reinforcement was attributed to poor particle-matrix bonding, as observed from scanning electron micrographs of the fracture surfaces. However, considerable reinforcement was observed when the nanocomposites were fabricated using an organofunctional silane to enhance particle-matrix interface strength. For the case of a 4.5% volume fraction of well-bonded Al2O3 particles added to the unsaturated polyester, the fracture toughness was increased by almost 100%.
Moral Knowledge: Some Reflections on Moral Controversies, Incompatible Moral Epistemologies, and the Culture Wars

An authentic Christian bioethical account of abortion must take into consideration the conflicting epistemologies that separate Christian moral theology from secular moral philosophy. Moral epistemologies directed to the issue of abortion that fail to appreciate the orientation of morality to God will also fail adequately to appreciate the moral issues at stake. Christian accounts of the bioethics of abortion that reduce moral-theological considerations to moral-philosophical considerations will not only fail to appreciate fully the offense of abortion, but morally mislead. This article locates the bioethics of abortion within the theology of the Church of the first millennium, emphasizing that abortion was prohibited, whether or not one considered the embryo or fetus to be ensouled.
Hip Arthroscopy: Current Indications, Treatment Options, and Management Issues

The management of hip injuries in athletes has evolved significantly in the past few years with the advancement of arthroscopic techniques. The application of minimally invasive surgical techniques has facilitated relatively rapid returns to sporting activity in both recreational and elite athletes. Recent advancements in both hip arthroscopy and magnetic resonance imaging have elucidated several sources of intraarticular abnormalities that result in chronic and disabling hip symptoms. Many of these conditions were previously unrecognized and, thus, left untreated. Current indications for hip arthroscopy include the presence of symptomatic acetabular labral tears, hip capsule laxity and instability, chondral lesions, osteochondritis dissecans, ligamentum teres injuries, snapping hip syndrome, iliopsoas bursitis, and loose bodies (for example, synovial chondromatosis). Less common indications include management of osteonecrosis of the femoral head, bony impingment, synovial abnormalities, crystalline hip arthropathy (gout and pseudogout), infection, and posttraumatic intraarticular debris. In rare cases, hip arthroscopy can be used to temporize the symptoms of mild-to-moderate hip osteoarthritis with associated mechanical symptoms. This article discusses the current clinical and radiographic methods to detect early hip joint disease and the current indications and surgical techniques of hip arthroscopy.
Problems in Strip Transmission Lines

A review is given of characteristic-impedance formulas for shielded-strip transmission lines. From these formulas a set of approximate relationships for the attenuation and Q of a dielectric-filled shielded-strip transmission line is derived. The method makes the standard assumption that the current distribution is that of a lossless line and the surface resistivity that of an infinite-plane condutor. Although this method applies accurately to most other types of lines, in this case an error of the order of 10% is believed to occur due to the failure of the assumptions at the corners of the strip. However, the error is in a direction that makes the computed values conservative, and the accuracy should be sufficient for most practical purposes. The derivation of a correction term is now being attempted. In addition to the discussion of attenuation attention is given in this paper to the design considerations involved in a shielded-strip-line impedance meter, and to some preliminary data obtained with this device. Also the future topics for investigation under this research and development program are mentioned.
Holoprosencephaly: genetic, neuroradiological, and clinical advances.

Recent advances in genetics and neurolmaging have greatly contributed to our understanding of the spectrum of midline brain and cranlofacial malformations known as holoprosencephaly. This review summarizes our current understanding of the epidemiology and molecular-genetic bases of these malformations, as well as recent neuroradiological and clinical studies, which have revealed that the manifestations of holoprosencephaly are far more variable than previously appreciated. We also discuss the implications for and importance of accurate diagnosis, prognosis, management of common medical problems, and counseling for affected famillies
A Delicate Balance: Homeostatic Control of Copper Uptake and Distribution

The cellular uptake and intracellular distribution of the essential but highly toxic nutrient, copper, is a precisely orchestrated process. Copper homeostasis is coordinated by several proteins to ensure that it is delivered to specific subcellular compartments and copper-requiring proteins without releasing free copper ions that will cause damage to cellular components. Genetic studies in prokaryotic organisms and yeast have identified membrane-associated proteins that mediate the uptake or export of copper from cells. Within cells, small cytosolic proteins, called copper chaperones, have been identified that bind copper ions and deliver them to specific compartments and copper-requiring proteins. The identification of mammalian homologues of these proteins reveal a remarkable structural and functional conservation of copper metabolism between bacteria, yeast and humans. Furthermore, studies on the function and localization of the products of the Menkes and Wilson's disease genes, which are defective in patients afflicted with these diseases, have provided valuable insight into the mechanisms of copper balance and their role in maintaining appropriate copper distribution in mammals.
Learning Behavior Fusion Estimation from Demonstration

A critical challenge in robot learning from demonstration is the ability to map the behavior of the trainer onto the robot?s existing repertoire of basic/primitive capabilities. Following a behavior-based approach, we aim to express a teacher?s demonstration as a linear combination (or fusion) of the robot?s primitives. We treat this problem as a state estimation problem over the space of possible linear fusion weights. We consider this fusion state to be a model of the teacher?s control policy expressed with respect to the robot?s capabilities. Once estimated under various sensory preconditions, fusion state estimates are used as a coordination policy for online robot control to imitate the teacher?s decision making. A particle filter is used to infer fusion state from control commands demonstrated by the teacher and predicted by each primitive. The particle filter allows for inference under the ambiguity over a large space of likely fusion combinations and dynamic changes to the teacher?s policy over time. We present results of our approach in a simulated and real world environments with a Pioneer 3DX mobile robot.
Pertussis Pathogenesis—What We Know and What We Don't Know

Pertussis is a worldwide public health threat. Bordetella pertussis produces multiple virulence factors that have been studied individually, and many have recently been found to have additional biological activities. Nevertheless, how they interact to cause the disease pertussis remains unknown. New animal models, particularly the infection of infant baboons with B. pertussis, are enabling longstanding questions about pertussis pathogenesis to be answered and new ones to be asked. Enhancing our understanding of pathogenesis will enable new approaches to the prevention and control of pertussis.
Active control of mixing in turbulent separated shear layers and effects of forcing on the fractal geometry of scalar interfaces

This paper explores effects of active control on mixing and the fractal geometry of scalar interfaces. In particular, a pulsed plasma actuator is used to implement active mixing control of turbulent-separated shear layers, with the advantage that this actuator has no moving parts. The effects on mixing are determined based on the scalar power spectrum and the scalar probability density function from scalar images recorded with laser Mie scattering for fog-seeded freestream air and pure ambient air. In addition, the fractal geometry of the scalar interfaces is examined to determine the effects of the forcing. The Reynolds number of the shear layer based on the visual thickness is 3.0 × 104 at the imaging station. The range of Strouhal numbers of the forcing is 0.3 ≤ St ≤ 7.8. Effects of forcing on the scalar power spectrum are found in terms of significant modifications of the spectral scalar energy at the lowest wavenumbers which is observed to increase by as much as 50% and decrease by as much as 40% dep...
Injury-Induced Changes in Liver Specific Transcription Factors HNF-1α and HNF-4α

Background The hepatic acute phase response(APR) is an organ-specific response to a diverse array of insults and is largely under transcriptional control. Liver-specific transcription factors, hepatic nuclear factors (HNFs)-1α and 4α play important roles in maintenance of liver phenotype and function and their binding activity changes early after injury. However, their roles in modulation of the liver’s response over time are not defined. Materials and Methods C57/BL6 mice were anesthetized and exposed to 95°C water for 10 s to create a 15% body surface area full-thickness burn. At specific time points, the mice were sacrificed. An ELISA for IL-6 was performed on serum and hepatic mRNA levels for fibrinogen-γ and serum amyloid A(SAA)-3 were obtained through polymerase chain reaction (PCR). Transcriptional factor binding activity was assessed with electrophoretic mobility shift assays. Results Serum IL-6 levels peaked at 3 h and fibrinogen-γ and SAA mRNA levels increased more than 6-fold at 12 h before returning to control levels at 48 h. The binding activity of HNF-4α and HNF-1α rapidly declined after injury (1.5 h) but recovered to near control level at 24 and 6 h, respectively. Conclusions Changes in HNF-4α and HNF-1α binding occurred before changes in acute phase protein mRNA levels and were preceded by the peak in IL-6 levels. The rapid suppression and reconstitution of liver-specific transcription factor binding after injury may represent a mechanism that allows the normal liver phenotype to change and an injury-response phenotype to prevail. This mechanism in the liver’s adaptive response to injury suggests a central role for both HNF-4α and HNF-1α in transcriptional regulation of the hepatic APR.
Expression of the Bacillus subtilis acsA Gene: Position and Sequence Context Affect cre-Mediated Carbon Catabolite Repression

In Bacillus subtilis, carbon catabolite repression (CCR) of many genes is mediated at cis-acting carbon repression elements (cre) by the catabolite repressor protein CcpA. Mutations in transcription-repair coupling factor (mfd) partially relieve CCR at cre sites located downstream of transcriptional start sites by abolishing the Mfd-mediated displacement of RNA polymerase stalled at cre sites which act as transcriptional roadblocks. Although the acsA cre is centered 44.5 bp downstream of the acsA transcriptional start site, CCR of acsA expression is not affected by an mfd mutation. When the acsA cre is centered 161.5 bp downstream of the transcriptional start site for the unregulated tms promoter, CCR is partially relieved by the mfd mutation. Since CCR mediated at an acsA cre centered 44.5 bp downstream of the tms start site is not affected by the mfd mutation, the inability of Mfd to modulate CCR of acsA expression most likely results from the location of the acsA cre. Higher levels of CCR were found to occur at cre sites flanked by A+T-rich sequences than at cre sites bordered by G and C nucleotides. This suggests that nucleotides adjacent to the proposed 14-bp cre consensus sequence participate in the formation of the CcpA catabolite repression complex at cre sites. Examination of CCR of acsA expression revealed that this regulation required the Crh and seryl-phosphorylated form of the HPr proteins but not glucose kinase.
Substituent effects in the mass spectral fragmentation of aryl esters

The mass spectra of m- and p-substituted phenyl acetates, phenyl propionates, phenyl chloroacetates and phenyl fluoroacetates have been determined. The fragmentation of aryl esters is affected by acyl substituents as well as by aryl substituents. Esters having acyl groups of low ionization potential show greater changes in fragmentation because of aryl substituents than those having acyl groups of high ionization potential. Each series has a fairly definite crossover point where fragmentation changes from predominant rearrangement to predominant cleavage.
A 8b 10Ms/s Low Power Pipelined A/D Converter

This paper describes an 8-bit, 10 MSamples/second analog to digital converter, with 2V fully differential input range, which is implemented in TSMC 0.25mum CMOS technology. It achieves low power dissipation of 25mW, and the chip area is 0.56mm2. Measured performance yields a very good VTC curve and a sine wave fitting curve for 200KHz input at 10Msample/s, DNL testing of -0.2LSB-0.75LSB; INL testing of -0.2LSB ~ 0.65LSB, 44.62dB of SNDR (signal to noise plus distortion ratio) and ENOB of 7.12 bits
Nesting Habitat of Least Terns (Sterna Antillarum Athalassos) on an Inland Alkaline Flat

Abstract We measured habitat characteristics in colony sites and at nest sites of endangered least terns (Sterna antillarum athalassos) on an expansive alkaline flat at Salt Plains National Wildlife Refuge, Oklahoma, in 1992 and 1993. Least terns nested in 12 colony sites on the alkaline flat during 1992 and 1993. Number of nests per colony site ranged from 5–25 and density of nests ranged from 0.1–0.75 nests/ha. Density of least terns in colony sites ranged from 0–2.1 terns/ha and was not correlated with soil color (P = 0.66) or soil texture (P = 0.12). Only a small percentage of ground cover was provided by vegetation (0.0–1.2%), driftwood (0.0–0.4%) and debris (0.0–1.1%) in colony sites. Least terns selected nest sites with coarser soil (loamy sand to sandy loam) than that of random points (P ≤ 0.0003). The coarser soils were lighter in color (P = 0.0001). Least tern nests were closer to driftwood or debris than random points (P = 0.0001). Internest distances in active colony sites ranged from 21.4 to ...