cssi/SciSciGPT-SciSciNet huggingface dataset:
On a Liouville-type comparison principle for solutions of semilinear elliptic partial differential inequalities

Abstract This Note is devoted to the study of a Liouville-type comparison principle for entire weak solutions of semilinear elliptic partial differential inequalities of the form L u + | u | q − 1 u ⩽ L v + | v | q − 1 v , where q > 0 is a given number and L is a linear (possibly non-uniformly) elliptic partial differential operator of second order in divergent form given formally by the relation L = ∑ i , j = 1 n ∂ ∂ x i [ a i j ( x ) ∂ ∂ x j ] . We assume that n ⩾ 2 , that the coefficients a i j ( x ) , i , j = 1 , … , n , are measurable bounded functions on R n such that a i j ( x ) = a j i ( x ) , and that the corresponding quadratic form is non-negative. The results obtained in this work complete similar results on solutions of quasilinear elliptic partial differential inequalities announced in Kurta [C. R. Acad. Sci. Paris, Ser. I 336 (11) (2003) 897–900]. To cite this article: V.V. Kurta, C. R. Acad. Sci. Paris, Ser. I 341 (2005).
Pioglitazone increases adiponectin levels in nondiabetic patients with coronary artery disease.

OBJECTIVES Hypoadiponectinemia is associated with coronary artery disease (CAD). Pioglitazone has been shown to increase levels of adiponectin in diabetic patients. We sought to assess whether administration of pioglitazone to patients with CAD and without diabetes would affect plasma adiponectin levels and endothelial function. METHODS Seventeen patients with stable CAD and without evidence of diabetes were treated for 12 weeks with pioglitazone hydrochloride 30 mg daily. Adiponectin levels and endothelium-dependent flow-mediated vasodilation (ED-FMD) measurements were obtained pretreatment, posttreatment, and after a 12-week washout period. RESULTS Treatment with pioglitazone increased adiponectin levels from an average of 10.6 to 21.1 microg/ml (P=0.001) and improved ED-FMD from 4.45 to 8.43% (P=0.001). CONCLUSION Treatment with pioglitazone increased plasma adiponectin levels and improved ED-FMD in patients with stable CAD and no evidence of diabetes or insulin resistance.
Pneumocystis carinii pneumonia in siblings.

Summary Two infant siblings with deficient immunoglobulins and Pneumocystis carinii pneumonia are presented. One infant died from Pneumocystis infection; the other one survived following early diagnosis and treatment with pentamidine. This is apparently the sixth reported instance of Pneumocystis pneumonia in siblings.
Reduced Expression of UGT1A1 in Intestines of Humanized UGT1 Mice via Inactivation of NF-κB Leads to Hyperbilirubinemia

Background & Aims Bilirubin is a natural and potent antioxidant that accumulates in the blood of newborn children and leads to physiological jaundice. Breastfed infants have higher serum levels of bilirubin than formula-fed infants and are at risk for bilirubin-induced neurological dysfunction (BIND). Clearance of bilirubin requires the expression of uridine diphosphate glucuronosyltransferase (UGT) 1A1; we investigated its role in the association between breast feeding with jaundice in mice. Methods We studied mice in which the original Ugt1 locus was disrupted and replaced with the human UGT1 locus ( hUGT1 mice); these mice spontaneously develop neonatal hyperbilirubinemia and BIND. We fed human breast milk or formula to neonatal hUGT1 mice and examined activation of the intestinal xenobiotic receptors pregnane X receptor and constitutive androstane receptor. We also examined inflammatory signaling pathways in mice with disruptions in IκB-kinase–α and IκB kinase–β in the intestinal epithelium. Results hUGT1 mice that were fed breast milk developed severe hyperbilirubinemia because of suppression of UGT1A1 in the gastrointestinal tract. Formula-fed hUGT1 mice had lower serum levels of bilirubin, which resulted from induction of UGT1A1 in the gastrointestinal tract. hUGT1/Pxr -null mice did not develop severe hyperbilirubinemia, whereas hUGT1/Car -null mice were susceptible to BIND when they were fed breast milk. Breast milk appeared to suppress intestinal IκB kinase α and β, resulting in inactivation of nuclear factor–κB and loss of expression of UGT1A1 , leading to hyperbilirubinemia. Conclusions Breast milk reduces expression of intestinal UGT1A1, which leads to hyperbilirubinemia and BIND; suppression of this gene appears to involve inactivation of nuclear factor–κB. Hyperbilirubinemia can be reduced by activation of pregnane X receptor, constitutive androstane receptor, or nuclear factor–κB.
The Growth of Medical Authority: Technology and Morals in Turn‐of‐the‐Century Obstetrics

Before 1880 birthing women and their female attendants dominated decisions concerning labor and delivery. Between about 1880 and 1920, however, the medical profession gained control of obstetrical care, and birth increasingly took place within hospitals. Using the specific example of the debate about performing craniotomies (the surgical mutilation of the fetal head to permit vaginal extraction) on live fetuses, the paper analyzes how technological innovations, changing medical theory, moral and ethical considerations, and professional interests interacted to make physicians more powerful arbiters in America's birthing rooms. Decisions surrounding cases of cephalopelvic disproportion, when major surgical interventions became essential, reveal most starkly the issue of control. Physicians learned to use such situations to increase the importance of what they felt was the uniquely scientific basis of their own contribution. The establishment of physicians' authority over emergency home-based deliveries in this turn-of-the-century period was a necessary prerequisite to their ultimate assumption of hospital-based authority.
Rational Design of a Chiral Palladium(0) Olefin Complex of Unprecedented Stability

A chiral bidentate olefin ligand L with a 1,4a,5,8a-tetrahydro-naphthalene-2,6-dione framework has been designed, which forms a homoleptic palladium(0) complex L2Pd of unprecedented stability.
Deep traps at MOCVD GaAs and regrown AlxGa1-xAs interfaces

Deep level transient spectroscopy (DLTS) of deep levels occurring at MOCVD grown and regrown interfaces is described as a function of surface preparation. We examine two types of interfaces: 1 ) nGaAs grown on SI-GaAs and 2) A10,1Ga0,9As regrowth on Alo.lGao,9As. Surface preparation includes both shallow and deep wet etching, passivation with (NH)2S, and in-situ heat treatments and HCL etching. A new electron trap with EcEa 0.1 1 eV and 1019 cm2 and a new minority carrier trap with Ea E 0.18 eV and 10-15 cm2 were found in GaAs samples. The minority carrier trap is related to sulphur passivation. Four traps were found in the AlGai..As regrown samples. It is demonstrated that (NH)2S passivation before MOCVD improves interface quality for both the GaAs and Al1Ga0,9As grown and regrown layers.
Comparison of terahertz versus infrared free-space communications under identical weather conditions

While both IR and THz/mmW wireless communications share some attributes such as line-of-sight signaling, their behaviors in response to various weather phenomena such as rain, fog, dust, and air turbulence can be quite different. The performance of mmW/THz and infrared free-space communication links are compared under the same weather conditions.
High-resolution diagnostic workstation development: initial clinical experience

Picture archival and communication (PACS) and teleradiology systems require workstations for image display, however not all areas demand the same functionality and performance. A comparison was made between the Vortech Personal Display System (PDS), the Dupont Clinical Review System (CRS), and the dual 2 K X 2.5 K Megascan Diagnostic Workstation (MDW) under development within the department.
Empirically studying the role of selection operators duringsearch-based test suite prioritization

Regression test suite prioritization techniques reorder test cases so that, on average, more faults will be revealed earlier in the test suite's execution than would otherwise be possible. This paper presents a genetic algorithm-based test prioritization method that employs a wide variety of mutation, crossover, selection, and transformation operators to reorder a test suite. Leveraging statistical analysis techniques, such as tree model construction through binary recursive partitioning and kernel density estimation, the paper's empirical results highlight the unique role that the selection operators play in identifying an effective ordering of a test suite. The study also reveals that, while truncation selection consistently outperformed the tournament and roulette operators in terms of test suite effectiveness, increasing selection pressure consistently produces the best results within each class of operator. After further explicating the relationship between selection intensity, termination condition, fitness landscape, and the quality of the resulting test suite, this paper demonstrates that the genetic algorithm-based prioritizer is superior to random search and hill climbing and thus suitable for many regression testing environments.
Phase changes in solids measured in a solar furnace ZrO2TiO2system

Abstract The liquidus curve of ZrO2TiO2 system was measured with a brightness pyrometer by the specular reflection method in a heliostat type solar furnace. An anomaly was found on 20 mole percent TiO2 composition as compared with the previously reported results. The quenched specimens of the system have also been investigated by x-ray technique and the decomposition of a compound, ZrTiO4, was discussed referring to the freezing point determination of an incongruently melting material.
Dissolved gallium in the open ocean

Greater understanding of the distributions and biogeochemical cycling of trace metals in the oceans has recently been attained due largely to advances in analytical chemistry and in trace metal sampling. We present here the first oceanographically consistent distribution of dissolved gallium in the open ocean, with concentrations 1–2 orders of magnitude lower than those reported previously1–3. The distribution of dissolved gallium is complex, indicating multiple sources and removal by scavenging throughout the water column.
Changing explanatory frameworks in the U.S. government’s attempt to define research misconduct

Nearly two decades of debate have not settled the definition of research misconduct. The literature provides four explanatory frameworks for misconduct. The paper examines these frameworks and maps them onto efforts by the U.S. Public Health Service to define research misconduct and subsequent responses to these efforts by the scientific community. The changing frameworks suggest that closure will not be achieved without an authoritative effort, which may occur through the Research Integrity Panel’s recent attempt to create a government-wide definition.
Portal and systemic drained pancreas transplants have similar outcomes

Abstract Introduction: Traditionally, the venous drainage of pancreatic allografts is to the iliac vein. Recently, drainage via the portal system has become increasingly popular, as this route is thought to result in reduced hyperinsulinemia and therefore be more physiologic.. Herein, we describe our institutional experience with systemic versus portal drainage. Methods: Data was collected from 36 consecutive pancreas transplant patients. Results, expressed as mean ± SEM, were analyzed by the unpaired t-test. Graft and patient survival underwent Kaplan-Meier analysis and Logrank testing. Results: During the study period, 29 pancreas recipients had systemic drainage while 7 had portal drainage. Anastomic time was 40.6 ± 3.4 minutes in the portal group and 40.9 ± 2.5 in the systemic group (p = NS). Five patients with systemic drainage had splenic thromboses, while none were seen in those with portal drainage. There were no significant differences in hospital length-of-stay. Glucose levels and HgbA1c levels were not significantly different (Figure). Interestingly, C-peptide levels were similar throughout the first postoperative week. Patient and graft survival were similar. Each group had one patient with acute cellular rejection. Conclusions: Venous drainage via the portal system has similar outcomes to systemic drainage. Since we anticipated enhanced first-pass hepatic clearance in the portal drained group, it was surprising that C-peptide levels were similar between the two groups. Download : Download high-res image (57KB) Download : Download full-size image
Topical clonidine produces mydriasis by a central nervous system action.

Abstract One drop of clonidine solution (0.125, 0.25 or 0.5%) was administered topically to one eye in cats anesthetized with pentobarbital in which the vagosympathetic nerves had been sectioned. Clonidine caused a simultaneous dose-related mydriasis in both eyes along with a decrease in heart rate. The peak effects were observed in about 20–30 min. Topical administration of clonidine (0.5%) produced no effect on the parasympathectomized, eserinized iris but did dilate the opposite pupil. Epinephrine (0.1–30 μg, i.a.) produced equal pupillary dilation in both eyes. In addition, topical clonidine caused a dramatic decrease in postganglionic ciliary nerve activity. All of the effects of clonidine were antagonized by yohimbine (0.5 mg/kg, i.v.). These results demonstrate that topical administration of clonidine causes mydriasis in the cat and that this effect is mediated totally by means of CNS inhibition of parasympathetic tone to the iris.
A study of steric and electronic factors governing the position of biofunctionalization of the benz(a)anthracene nucleus: Metabolism in vitro of fluoro- and methyl-substituted analogs

Abstract Metabolism of selected fluoro and methyl analogs of benz(a)anthracene were studied in induced and uninduced rat liver S-10 fractions. Examination of the various metabolites produced from these substrates led to the conclusion that both steric and electronic factors determine the preferential sites of bioactivation. A hypothesis is proposed to explain the results.
A Two Colorable Fourth Order Compact Difference Scheme and Parallel Iterative Solution of the 3D Convection Diffusion Equation

A new fourth order compact difference scheme for the three dimensional convection diffusion equation with variable coefficients is presented. The novelty of this new difference scheme is that it Only requires 15 grid points and that it can be decoupled with two colors. The entire computational grid can be updated in two parallel subsweeps with the Gauss-Seidel type iterative method. This is compared with the known 19 point fourth order compact differenCe scheme which requires four colors to decouple the computational grid. Numerical results, with multigrid methods implemented on a shared memory parallel computer, are presented to compare the 15 point and the 19 point fourth order compact schemes.
A support vector machine (SVM) approach to imbalanced datasets of customer responses: comparison with other customer response models

Customer response is a crucial aspect of service business. The ability to accurately predict which customer profiles are productive has proven invaluable in customer relationship management. An area that has received little attention in the literature on direct marketing is the class imbalance problem (the very low response rate). We propose a customer response predictive model approach combining recency, frequency, and monetary variables and support vector machine analysis. We have identified three sets of direct marketing data with a different degree of class imbalance (little, moderate, high) and used random undersampling method to reduce the degree of the imbalance problem. We report the empirical results in terms of gain values and prediction accuracy and the impact of random undersampling on customer response model performance. We also discuss these empirical results with the findings of previous studies and the implications for industry practice and future research.
A mathematical analysis of oxygen respiration in man

By means of physicomathematical models similar to those used by A. B. Chilton and R. W. Stacy (1952) formulas are obtained for the purpose of analyzing oxygen respiration in man under conditions of metabolic equilibrium. The formulas are applied to conditions involving a variety of physiological assumptions. Calculated quantities are shown to be in agreement with experimental values. A quantitative prediction is made of the fluctuation in alveolar oxygen tension over a single respiratory cycle. Finally, calculations are completed for all alveolar gases; and the over-all results are shown to be self-consistent to the degree expected in view of the simplifying approximations made.
A novel link between Tourette's syndrome and histaminergic signalling

l-Histidine decarboxylase and Tourette's syndrome Ercan-Sencicek et al. (2010) The New England Journal of Medicine 362(20): 1901–1908
Inducible expression bovine papillomavirus shuttle vectors containing ferritin translational regulatory elements

Abstract The combination of transcriptional and translational control elements in an inducible expression vector suitable for use m stably transformed cell lines was explored. To this end, ferritin translational control elements have been inserted downstream from a mouse metallothionein (mMT-I) transcriptional promoter (PmMT-I), and upstream from various reporter protein-encoding open reading frames (ORFs), all carried on a bovine papillomavirus shuttle vector. Protocols which stimulate transcription (with zinc) and translation (with iron) were developed to optimize the induction of reporter protein synthesis. It was found that insertion of an iron regulatory element between the PmMT-I and a reporter ORF bestowed a sixfold inducibility of reporter protein synthesis with iron and a 90-fold inducibility with iron plus zinc in a classical superinduction protocol. Surprisingly, inclusion of other rabbit ferritin light chain sequences (rFL), including the ORF, enhanced reporter inducibilities to over 15- and 500-fold, respectively. These additional rFL sequences not only increased inducibility but also (i) increased the half-life of the mRNA and (ii) strongly inhibited translation of an ORF located downstream from the 5′ proximal ORF. The maximum levels of reporter proteins attained in transformed cells after prolonged induction represented from 1% to 7% of total cellular protein. These inducible expression vectors should prove useful for the production and study of cytotoxic proteins.
Profile of glycosaminoglycan-degrading glycosidases and glycoside sulfatases secreted by human articular chondrocytes in homeostasis and inflammation.

Objective To determine enzymatic activities of the 8 key glycosaminoglycan-degrading glycosidases and glycoside sulfatases in cultured human articular chondrocytes and in synovial fluid from patients with osteoarthritis. Methods The following enzymes were analyzed: hexosaminidase and its isoenzyme A, N-acetyl-α-D-glucosaminidase, β-galactosidase, β-glucuronidase, α-L-iduronidase, aryl sulfatase, and galactose-6-sulfate sulfatase. Activity of the selected enzymes was analyzed by fluorometry with the aid of 4-methylumbelliferryl derivatives of the appropriate monosaccharides. Results Hexosaminidase was found to be the dominant enzyme released by chondrocytes into the extracellular compartment. Stimulation of chondrocytes with interleukin-1β resulted in a selective increase of the extracellular hexosaminidase activity and, to a lesser degree, of the extracellular β-galactosidase activity, without significant changes in the activity of the other studied enzymes. Analysis of the pH dependency of the enzymatic activities revealed that even at neutral pH, hexosaminidase expressed a measurable activity, much higher than the activity of the other studied enzymes. Chondrocyte apoptosis did not result in increased extracellular glycosidase activities, including hexosaminidase activity. The spectrum of glycosidase and glycoside sulfatase activities in the synovial fluid from patients with osteoarthritis was similar to that in cultured human articular chondrocytes. Conclusion These data support the concept that lysosomal glycosidases, in particular hexosaminidase, represent a distinct subset of cartilage matrix–degrading enzymes that are activated by proinflammatory stimuli.
Kinetics and mechanism of the epimerization and decomposition of threonine in fossil foraminifera

Abstract Determination of alloThr/Thr ratios in foraminiferal tests ranging in age from Recent to ∼ 700,000 yr B.P. has shown that threonine epimerization ratios approach a steady-state value of ∼0.2. This is well below the equilibrium ratio of ∼0.9 as measured in buffered aqueous solutions. It has also been found that the initial rate of decomposition of threonine in fossil foraminfera is about an order of magnitude faster than would be predicted on the basis of extrapolation from high temperature kinetic studies on free threonine in buffered aqueous solution. These results are apparently a consequence of metal cation catalysis of both the decomposition and the epimerization of free threonine, which is being continually released by the slow hydrolysis of peptide and proteinaceous material present in the fossil shells.
Electron microscopic study of the transition from amorphous to crystalline condition of electron bombarded cadmium sulfide films

Abstract Amorphous to crystalline transformation of CdS thin films is produced by electron beam bombardment and studied by electron-microscopy.
Psychiatric morbidity in the relatives of patients with DSM-III schizophreniform disorder: Comparisons with the relatives of schizophrenic and bipolar disorder patients

Risks for psychiatric disorders (RDC) among first degree relatives of DSM-III schizophreniform, bipolar, and schizophrenic probands obtained from an epidemiologic sample using family history methods were examined. The relatives of the schizophreniform probands differed from the relatives of the schizophrenic and bipolar probands. The relatives of schizophreniform probands had significantly higher rates of affective illnesses (with the exception of bipolar illness) than the relatives of schizophrenic probands, and they had a significantly higher rate of psychotic affective disorders than the relatives of the bipolar probands.
The addition of 5′ cap structures occurs early in hnRNA synthesis and prematurely terminated molecules are capped

After cells were labeled by brief exposure to 3H-methyl-L-methionine, the majority of labeled 5' terminal cap I (m7GpppN1mpN2p) oligonucleotide structures were in nuclear RNA (hnRNA) molecules approximately 750 nucleotides or less in length. After longer label times, the proportion of cap I structures in nuclear molecules longer than mRNA rose to approximately 60% of the total, but approximately 40% of the cap I structures were still in molecules shorter than approximately 750 nucleotides. The cap I structures in both long and short hnRNA chains contained all four 2' methylated nucleotides in the N1 position in about the same proportion as in mRNA. None of the large hnRNA molecules could be demonstrated to contain 5' pppX p termini; the only such terminus in high molecular weight RNA was pppAp which was decreased markedly by low doses of actinomycin and is presumably the terminus of pre-rRNA. These results raise the possibilities that hnRNA chains can initiate with any of the four nucleotides, that capping occurs very close to or at the start of hnRNA chain synthesis and that approximately 40% of the hnRNA chains may be prematurely terminated.
Return to ranger submarine slide, Baja California, Mexico

Ranger Slide is a modest (12 km3) slide deposit of Pliocene and younger sediment on the continental slope in northern Sebastian Vizcaino Bay, Mexico. A limited survey using a deeply-towed instrument shows that hummocky terrain immediately downslope from the slide scar consists of large blocks of semiconsolidated sediment, some exceeding a kilometer in length and 107 m3 in volume. Most blocks have rotated, fallen apart, and/or deformed during movement. The form, structure, and processes related to emplacement of the blocks within the hummocky topographic zone of Ranger Slide may be common to many submarine slides on slopes involving semiconsolidated, terrigenous sediment.
Biochemical and ultrastructural studies on the interaction of basic proteins with mitochondria: A primary effect on membrane configuration

Abstract Basic proteins stimulate oxygen consumption, extrusion of potassium, and “swelling” of isolated liver mitochondria. The movement of potassium is not required for the action of basic proteins on mitochondria. Despite a prior depletion of potassium by low concentrations of nigericin, basic proteins still stimulate respiration and decrease light scatter. Concomitant with the biochemical events noted, basic proteins cause a change in the mitochondrial ultrastructure from the “condensed” configuration typical of state 4 mitochondria to a configuration more typical of state 3 mitochondria. These studies suggest that the primary action of basic proteins involves an energy-dependent, structural alteration in the mitochondrial membrane.
Cardiocirculatory responses to muscular exercise in congestive heart failure

T HE PURPOSE of this review is to delineate current knowledge of the cardiocirculatory adjustments that accompany physical exercise in clinical congestive heart failure. To provide the necessary background information for understanding such a discussion, it is first important to concisely consider the cardiac and peripheral circulatory responses operative in normal individuals during exertion. Thus, the first section describes the normal responses of the heart to muscular exercise and those of the systemic vasculature to physicial stress. Then, proceeding from this fundamental information, the principal portion of this review is focused on the series of systematic studies, largely carried out in our laboratories, to elucidate the cardiocirculatory mechanisms in the congestive heart failure state.
How can the specialty establish a standard of care

T he development of basic tools for assessing orthodontic care is an important initial step in establishing a standard of care. It should be part of the purpose of clinical research. What has occurred in the dental model, specifically in orthodontics? Outside certain structural criteria such as those promulgated by the American Dental Association, American Association of Orthodontists (AAO) guidelines for accreditation of orthodontic teaching, and the recent AAO guidelines for ‘‘quality assessment of orthodontic care,’’ few, if any, process and outcome criteria have been suggested, let alone published, recommended, or stated as standard of care criteria. A standard of care has not been defined, proven, or taught (as such) in orthodontics. Why is this? As an excuse for an answer, it is generally suggested that no reliable data have yet been collected on which guidelines or standards can be based. Although many orthodontic clinical reports appear in the journals, few are reports of randomized clinical trials. Few studies use random allocation for a treatment trial, with half of the patients treated and half assigned as controls without intervention. Most clinical reports are case series studies. Sackett stated that ‘‘case series, though often thought-provoking, are prone to over-interpretation, especially by their authors. Because of their methodological weakness, case series are best used to stimulate or pilot other, more powerful, investigations.’’ All too often, however, they provoke authoritarian rather than authoritative clinical advice about etiology, prevention, and therapy. Readers of these reports seldom consider the clinical research methods used before
Solution to an Inverse Problem in Diffusion

Finitely many measurements suffice to express in closed form the parameters of a linear diffusion and absorption within a homogeneous and isotropic medium in any dimension.
A Comparison Study for Determining Dissolved Boron in Natural Water and Geothermal Fluid

Abstract A comparison study was undertaken to evaluate different analytical methods for measuring boron concentrations in the geothermal fluid from the Los Alamos Hot Dry Rock Geothermal Energy Project and from natural waters collected in the vicinity of the project. Three colorimetric techniques, the carmine method and two azomethine H methods, were compared with two plasma emission spectroscopy methods and with thermal neutron capture-gamma spectroscopy. In general, the analytical results from all the methods were comparable and acceptable; however, each method had its own distinct advantages and disadvantages.
Watershed‐management from the viewpoint of the forester

American foresters have been ardent propagandists and zealots in the cause of watershed-conservation. Their claims that forests and a mantle of vegetation ameliorate or prevent floods, accelerated erosion and silting of streams and reservoirs have been, however, seriously questioned. For 25 years this controversy has continued, the foresters being charged as extremists with no facts to support their philosophy on watershed-protection. These contentious discussions chiefly between engineers, meteorologists, and foresters nave produced a voluminous literature; but in spite of this, floods and drouth continue to plague us.
Generation and Characterization of Isolated Attosecond Pulses for Atomic and Molecular Physics

Abstract (35 Word Limit) We will review recent experimental progress in the generation, characterization and application of XUV pulses, produced by high-order harmonic generation in gases, with duration down to the attosecond time scale.
Implanted-planar-buried-heterostructure, graded-index, separate-confinement-heterostructure laser in GaAs/AlGaAs

For the implanted planar buried-heterostructure, graded-index, separate-confinement-heterostructure (IPBH-GRINSCH) laser in (AlGa)As/GaAs, ion implantation is used to form p-n-p-n current blocking layers and to create a buried-heterostructure waveguide. This results in significantly reduced fabrication complexity of high-quality, index-guided laser diodes compared to regrowth techniques, and in contrast to diffusion-induced disordering, allows for the creation of self-aligned, buried, blocking junctions. Kink-free, CW operation of single-stripe IPBH-GRINSCH lasers along with single-lobed near-field and far-field optical emission patterns, consistent with index-guided operation, is demonstrated. >
Low Cost, Tailored Polymer-Metal Nanocomposites for Advanced Electronic Applications

The primary purpose of this paper is to introduce a nanomaterials fabrication facility that has recently been set up at the University of Alaska Fairbanks' Office of Electronic Miniaturization (OEM). The secondary purpose is to outline our research programs on nanoengineered materials for advanced electronic applications. We present a versatile, simple, and single-step high-vacuum e-beam codeposition technique for the controlled fabrication of nanostructured materials. The method allows evaporation of up to four different polymers, metals, semiconductors, insulators, and ceramics simultaneously or sequentially. Film properties can be controlled by controlling a number of deposition conditions. The system can be switched over rapidly to use a different set of materials. The process has a great potential to produce materials for many different practical applications for both R&D and scaled-up pilot production. This is the first nanomaterial fabrication facility of its kind in the State of Alaska and provides exciting opportunities for university-government- industry-collaboration that will be highlighted.
The Expression of CD45RB on Antigen-Responsive CD4+ Lymphocytes: Mouse Strain Polymorphism and Different Responses to Distinct Antigens

The levels of CD45RB expression by HGG-specific CD4+ cells residing in the Ag-draining lymph nodes of HGG-primed CBA/CaJ mice were analyzed. When sorted populations of CD4+, CD45RBhi, and CD4+, CD45RBlo cells were cultured with HGG and Ag-presenting cells, the majority of the proliferative response was found in the CD45RBlo fraction early after in vivo priming (Day 6), and this pattern remained stable through 12 days postpriming. To determine whether this segregation of responsiveness was consistent in other mouse strains, HGG-primed C57BL/6J mice were similarly analyzed. In contrast to findings with the CBA/CaJ strain, the CD4+, CD45RBhi cell fraction obtained from C57BL/6J mice was the predominant responding population early after in vivo priming (Day 6); however, there was a parallel increase in responsiveness of CD4+, CD45RBhi, and CD4+, CD45RBlo cells by Day 12. Thus, there was not a decrease in CD45RBhi expression with a concommitant increase in CD45RBlo expression in CD4+ cells proliferating to HGG. Despite the heterogeneity in CD45RB expression by the primed CD4+ cells of the two strains, the entire proliferative response to HGG early after priming resided in the fraction bearing high levels of membrane CD44, thus arguing for the existence of CD45RBhi, CD44hi and CD45RBlo, CD44hi cells during the early phase of the response. In both mouse strains the CD4+, CD45RBhi subset of primed lymph node cells produced significant levels of IL-2 in response to HGG and APC, whereas no significant IL-2 or IL-4 production was detectable in HGG-stimulated CD45RBlo cells of either strain. The CD4+, CD45RBhi subset also proliferated more vigorously in response to polyclonal activation than the CD4+ CD45RBlo fraction. To examine whether the patterns of CD45RB expression on HGG-primed cells from C57BL/6J mice were common to other antigens, the response profiles were examined after in vivo priming with a second antigen, KLH. In contrast to studies with HGG as the Ag, the proliferative response to KLH in C57BL/6J mice was evenly divided among the CD45RBhi and CD45RBlo fractions on Day 8 after priming, but shifted markedly to the CD45RBlo fraction by Day 12 after priming. Taken together, these data show that the patterns of CD45RB expression on primed populations of CD4+ cells can exhibit mouse strain polymorphism and can differ depending on the choice of antigen for immunization.
A comparative study of the effects of freezing and frozen storage on intact and demembranated bull spermatozoa.

The damage caused to bull sperm by freezing and thawing them without cryoprotectants was assessed in both intact and membrane-extracted cells. Preparations of membrane-extracted cells were produced by treating the sperm with 0.1% Triton X-100 and motility was restored with exogenously applied ATP and Mg2+. Motile demembranated sperm showed no detectable reduction in motility after freezing and thawing. In contrast, when intact cells where subjected to freezing and thawing they lost all motility. These damaged cells were also restored to motility when exogenous ATP and Mg2+ were added to the sperm mixture. Apparently freezing and thawing sperm cells causes damage to the plasma membrane which permits ATP and Mg2+ to freely enter or leave the cells, but does not damage the components of the sperm cell which generate motility. The effects of storage temperature on frozen demembranated sperm were also explored. Sperm held at −20 °C showed marked structural changes and progressively decreased motility after prolonged storage. When sperm were frozen at −20 °C the mitochondrial structures were completely lost after 48 to 72 hr and ATP caused the disintegration of the flagellum rather than initiating motility. Sperm which were frozen at −76 °C retained motility after short periods of storage, but showed a significant decline in motility when thawed after 8 days. Demembranated sperm which were kept frozen at −196 °C showed no significant loss of motility when thawed after 1 year of storage.
Multiple coronary artery-left ventricular fistulas: A pattern of anomalous coronary microvascularization

Fistulas between the coronary artery and the left heart chambers are exceptionally rare, especially those emptying into the left ventricle. We know of 33 cases of coronary artery-left ventricular fistulas reported in the literature, 7 of which had multiple communications. The findings in 6 additional patients with multiple coronary artery-left ventricular fistulas are reported. Three of the 6 patients had fistulas communicating to the left ventricle from all three major coronary arteries. It is important to recognize this anomaly as it may be the source of angina in patients without angiographic evidence of major atherosclerotic coronary artery disease.
Stratigraphy, age and environments of the late Miocene Mpesida beds, Tugen Hills, Kenya

Abstract Interpretations of faunal assemblages from the late Miocene Mpesida Beds in the Tugen Hills of the Central Kenyan Rift Valley have figured prominently in discussions of faunal turnover and establishment of the modern East African communities. These faunal changes have important implications for the divergence of the human lineage from the African apes ca. 8–5 Ma. While fossil material recovered from the Mpesida Beds has traditionally been analyzed collectively, accumulating evidence indicates that Mpesida facies span the 7–6 Ma interval and are scattered more than 25 km along the eastern flanks of the Tugen Hills. Stratigraphic distinctions between Mpesida facies and younger sediments in the sequence, such as the Lukeino Formation, are not yet fully resolved, further complicating temporal assessments and stratigraphic context of Mpesida facies. These issues are discussed with specific reference to exposures of Mpesida facies at Rurmoch, where large fossil tree fragments were swept up in an ancient ash flow. Preserved anatomical features of the fossil wood as well as estimated tree heights suggest a wet, lowland rainforest in this portion of the rift valley. Stable isotopic analyses of fossil enamel and paleosol components indicate the presence of more open habitats locally. Overlying air-fall tuffs and epiclastic debris, possibly associated with the ash flow, have yielded an assemblage of vertebrate fossils including two teeth belonging to one of the earliest colombines of typical body size known from Africa, after the rather small Microcolobus. Single-crystal, laser-fusion,40Ar/39Ar dates from a capping trachyte flow as well as tuffs just below the lava contact indicate an age of greater than 6·37 Ma for the fossil material.
Pubertal timing of Latinas and school connectedness during the transition to middle school.

During the middle school transition, adolescents are often faced with physical and school contextual changes that may impact how they perceive that first transitional year. The present study examined how pubertal timing (onset of menarche) was associated with Latinas’ school connectedness during the first year in middle school and whether that relationship was moderated by perceived school ethnic composition and body mass index (BMI) (i.e., a reliable indicator of body fat calculated from participants’ age, height, and weight). Sixth-grade Latinas (N = 609) at the beginning and end of the first year of middle school indicated whether menarche had begun. From this question, girls were classified as early maturers (started menarche before 6th grade), changers (started during 6th grade) or later maturers (had not started by the end of 6th grade). Changers who attended schools where they perceived fewer same-ethnic peers and they deviated from the Latina BMI mean of that school in the direction of lower BMI (i.e., toward being underweight), reported more school connectedness than early and later-maturing Latinas. These findings underscored the importance of finding one’s niche and fitting in for girls who are maturing during a period of both rapid physical change and a school transition.
Early Perceptual Strategies for the Replication of Consonants from Polysyllabic Lexical Models

Perceptual processing strategies for the selection and organization of consonants for early replicas of polysyllabic models were investigated as a related study to the classification of productive strategies (Klein, 1981). The present study investigated the ways in which selected word factors (stress level and serial position of the syllable) provided facilitating cues for the production of polysyllabic words. The original procedure involved collecting a language sample from four children (ages 20-24 months) as each informally interacted with an adult during a play activity that included the manipulation of palpable and picturable objects represented by polysyllabic words. This paper focuses specifically on the perceptual strategies of only two of the four children; each demonstrated equally consistent but dissimilar production patterns. Each child's perceptual strategy is described on the basis of the proportion of instances that his/her consonant replicas could be related with the occurrence of specific...
A Quantitative Approach to Speckle Reduction via Frequency Compounding

Coherent speckle is a source of image noise in ultrasonic B-mode imaging. The use of multiple imaging frequencies has been suggested as a technique for speckle contrast reduction. This technique involves the averaging of images whose speckle patterns have been modified by a change in the spectrum of the transmitted or received acoustical pulse. We have measured the rate of this speckle pattern change in ultrasonic images as a function of the change in center frequency of the transmitted acoustical pulse. This data is used to quantitatively describe the trade-off of resolution loss versus speckle reduction encountered when frequency compounding is employed and to derive the optimal method of frequency compounding. These results are then used as a basis for describing the overall advisability of frequency compounding in ultrasonic imaging systems. Our analysis indicates that simple frequency compounding is counterproductive in improving image quality.
Extracting randomness from samplable distributions

The standard notion of a randomness extractor is a procedure which converts any weak source of randomness into an almost uniform distribution. The conversion necessarily uses a small amount of pure randomness, which can be eliminated by complete enumeration in some, but not all, applications. We consider the problem of deterministically converting a weak source of randomness into an almost uniform distribution. Previously, deterministic extraction procedures were known only for sources satisfying strong independence requirements. We look at sources which are samplable, i.e. can be generated by an efficient sampling algorithm. We seek an efficient deterministic procedure that, given a sample from any samplable distribution of sufficiently large min-entropy, gives an almost uniformly distributed output. We explore the conditions under which such deterministic extractors exist. We observe that no deterministic extractor exists if the sampler is allowed to use more computational resources than the extractor. On the other hand, if the extractor is allowed (polynomially) more resources than the sampler, we show that deterministic extraction becomes possible. This is true unconditionally in the nonuniform setting (i.e., when the extractor can be computed by a small circuit), and (necessarily) relies on complexity assumptions in the uniform setting.
Body image distortion in anorexics as a non-sensory phenomenon: a signal detection approach.

Body image in anorexic and normal weight female subjects was investigated with a video TV monitor. Eighteen subjects were presented with a task in which they manipulated their body size to obtain “ideal” and actual images and a task wherein they judged the accuracy of a projected image of their body. There were no differences in estimated actual body size between anorexics and control subjects. For both groups, ideal images were below their actual image. For the second task, a signal detection analysis revealed no sensory sensivitity differences between weight groups. Anorexic subjects were more likely to report and image of themselves as distorted, regardless of whether distortion was present. Both weight groups adopted a strict criterion when they were viewing a heavy image of themselves. The finding that body estimation difference between anorexics and controls is non-sensory are discussed, and ramifications for treatment of anorexia are described.
Efficient Sensor Management Policies for Distributed Target Tracking in Multihop Sensor Networks

We consider the problem of distributed target tracking in a sensor network under communication constraints between the sensor nodes, a problem that has recently received significant attention. Communication constraints limit sensor data fusion in two ways. It significantly constrains sensor communication across large distances and substantially limits the number of sensors participating in data fusion at any time instant. We explore sensor management policies, i.e., sensor selection under communication constraints, for distributed target tracking. The coupled problem of track estimation and sensor management is generally intractable and significant effort has been devoted towards proposing simple strategies under various performance criteria. In this paper, we adopt a certainty equivalent approach and separate the tasks of track estimation and sensor management. Our approach is an adaptive dynamic strategy for sensor selection that seeks to optimize a tradeoff between tracking error and communications cost. We formulate the sensor management problem for the limiting case of infinite sensor density and derive sensor selection policies for different classes of target dynamics and sensor measurements. Under assumptions of a regular dense network with homogeneous sensors, the optimal strategy is a hybrid switching strategy, where the fusion center location and reporting sensors are held stationary unless the target estimates move outside of a threshold radius around the sensors. We simulate different tracking scenarios to illustrate the performance of our algorithms on sensor networks. We show that the computational as well as the communication costs are constant and do not scale with network size. We also perform different parametric studies to illustrate the validity of our approximations.
A Simple Model of Legislator and News Media Interaction

This article examines the effect of a strategic news media on legislators' interactions with their constituencies. Specifically, legislators can only be constrained by constituency preferences over policies when voters have the information to hold legislators accountable for their actions. A strategic news media can provide such information in a constant and continuous manner unlike, say, challengers. This article addresses this scenario with several models. First, a signaling model is introduced with constituency preferences and a journalist's investigating and reporting strategies serving as constraints on a legislator's voting preferences. Results of the baseline model include a pooling equilibrium where legislators vote with the district and are always re-elected. Second, a basic ultimatum bargaining model is introduced to allow for collusion between journalists and legislators in the output of the news product. This extension highlights a pure strategy-separating equilibrium where an out-of-step legi...
Starch-based nanocomposites by reactive extrusion processing

Nanocomposites with unique material properties have been prepared from synthetic plastics and nanosilicates (nanoclay) until now, but not from biopolymers such as starch. The primary challenge in making biopolymeric nanocomposites is to achieve strong adhesion between nanoclay and polymer matrix. For the first time nanocomposites with superior properties have been successfully made from starch-polycaprolactone (PCL) blends in the presence of montmorillonite (MMT) nanoclay. Reactive extrusion results showed that addition of a modified nanoclay at 3 % wt level increased elongation almost fourfold over that of pristine starch–PCL blends. X-ray diffractions results showed dispersion of clay in the polymer matrix. The nanocomposites have better solvent-resistance properties because of resistance to diffusion offered by clay platelets in the polymer matrix. Copyright © 2004 Society of Chemical Industry