cssi/SciSciGPT-SciSciNet huggingface dataset:
Generality of test-session observations to kindergarteners' classroom behavior.

Test observations are integral components in the comprehensive assessment of children's academic talents and personal adjustment. They are used to validate standardized test scores obtained during test sessions and to draw inferences about children's general pattern of learning and social adjustment. Unfortunately, little empirical justification exists for extending inferences beyond the confines of test sessions. This issue was examined with 155 kindergarten children using the Stanford Binet Observation Schedule (SBOS), a popular instrument for the summative integration of test-session observations. Children's ratings on the SBOS were used to estimate teacher-observed behavior on the Guide to the Child's Learning Style (GCLS). SBOS and GCLS scores were subjected to independent principal components analyses with varimax rotation and, thereafter, to a joint canonical variance analysis. Weighted factor composites from two SBOS dimensions constituted the predictor data set and three GCLS dimensions the criterion data set. Although multivariate statistical significance was achieved (λ=.834, F (6, 200)=3.18, p<.005), cannonical redundancy showed merely 9.4% of classroom behavior predictable from test-session. Results are examined in light of research on the situational specificity of behavior.
Single-layer TiO(2) and multilayer TiO(2)-SiO(2) optical coatings prepared from colloidal suspensions.

Single-layer coatings on fused silica substrates have been prepared from aqueous colloidal suspensions of titania at room temperature. These coatings were porous and had a refractive index of 1.9. Multilayer high reflectivity dielectric coatings were also prepared by laying down quarterwave thick alternating coats at room temperature of this titania with silica, prepared from a colloidal suspension of silica. Single-shot laser damage threshold measurements at 1064-nm wavelength with a pulse length of 1 ns were carried out for both the titania and titania-silica systems. These averaged 7.5 and 6.2 J/cm2, respectively.
Glutamine transaminase K and cysteine S-conjugate β-lyase activity stains

An activity stain to detect glutamine transaminase K subjected to nondenaturing polyacrylamide gel electrophoresis (ND-PAGE) was developed. The gel is incubated with a reaction mixture containing L-phenyl-alanine, alpha-keto-gamma-methiolbutyrate (alpha KMB), glutamate dehydrogenase, phenazine methosulfate (PMS) and nitroblue tetrazolium (NBT). Glutamine transaminase K catalyzes a transamination reaction between phenylalanine and alpha KMB. The resultant methionine is a substrate of glutamate dehydrogenase. The NADH formed in the oxidative deamination of methionine reacts with PMS and NBT to form a blue band on the surface of the gel coincident with glutamine transaminase K activity. Cysteine S-conjugate beta-lyase activity is detected in the gel by incubating the gel with a reaction mixture containing alpha KMB (to ensure maintenance of the enzyme in the pyridoxal 5'-phosphate form), S-(1,2-dichlorovinyl)-L-cysteine (DCVC), PMS, and NBT. The products of the lyase reaction interact with PMS and NBT to form a blue dye coincident with the lyase activity. In addition, a new assay procedure for measuring cysteine S-conjugate beta-lyase activity was devised. This procedure couples pyruvate formation from DCVC to the alanine dehydrogenase reaction. Preparations of purified rat kidney glutamine transaminase K yield a single protein band on ND-PAGE (apparent Mr approximately 95,000). This band coincides with both the cysteine S-conjugate beta-lyase and glutamine transaminase K activities. Activity staining showed that homogenates of rat kidney, liver, skeletal muscle, and heart possess a glutamine transaminase K/cysteine S-conjugate beta-lyase activity with an Rf value on ND-PAGE identical to that of purified rat kidney glutamine transaminase K.(ABSTRACT TRUNCATED AT 250 WORDS)
A histochemical study of muscle spindles and their relationship to extrafusal fiber types in the rat

Hindlimb muscles of the rat were studied in serial section with enzyme histochemical methods. Muscle fibers, both extrafusal and intrafusal, were compared as to their relative succinic dehydrogenase and phosphorylase activity, indicative of oxidative and glycolytic metabolism respectively. The superficial fascicles of a number of white (fast-twitch) muscles are composed almost exclusively of glycolytic (type A) muscle fibers, whereas the deep fascicles contain a mixture of oxidative (type B) and oxidative-glycolytic (type C) fibers. Muscle spindles are found only among the deep fascicles of these fast muscles. Neither the soleus, a red (slow-twitch) muscle comprised mainly of type B fibers, nor the middle lumbrical muscles, with a fairly uniform distribution of several fiber types, exhibit so specific a spindle disposition. Thus a close spatial relationship exists between spindles and certain types of muscle fibers, presumbly representing specific types of motor units. Within the spindles, the nuclear-bag intrafusal fibers are generally of types A and B, and of a third variety characterized by both low oxidative and low glycolytic activity. The latter fiber-type is not commonly observed in the extrafusal musculature. Nuclear-chain intrafusal fibers resemble type C fibers. Speed of contraction and enzymes of energy metabolism of extrafusal fibers are known to be neurally regulated. The several types of histochemically distinguishable intrafusal fibers probably reflect differences in motor innervation and possibly differing contraction-kinetics.
A finiteness property of affine algebras

Let A be a finitely presented reduced commutative k-algebra and J an ideal in A. If A embeds in A/J then J = 0. 1. STATEMENT OF THE PROBLEM We consider the following situation that arose in a technical context in [B]. K= a commutative ring. A = a commutative K-algebra. J = an ideal in A. f: A -* A/J is an injective K-algebra homomorphism. We want to conclude that J = 0 under suitable finiteness assumptions. (1.1 ) Theorem. Assume: (FP) A is a finitely presented K-algebra; and (Red) A is reduced (i.e., all nilpotent elements are zero). Then J = O. The following examples illustrate the necessity of the hypotheses (FP) and (Red). (1.2) Example. Let (xn)n>o be a sequence of indeterminates, A = K[(xn)n0], J = Axo, so that A/J = K[x1, X2, x3, ...], and define f: A A/J by f(xn) = xn+1 (mod J) for n > 0. Here A is reduced (and finitely related), but not finitely generated. I do not know if one can relax (FP) and require only that A be finitely generated. (1.3) Example. Let R = K[x], a polynomial ring in one variable. Let M = Ru E Rv, a free R-module with basis u, v. Put A= R ED M with MA2 = 0, and let J = Av = Rv . Then A/J = REDRu with u2 = 0. Define f: A -+ A/J to be the K-algebra homomorphism such that f(x) = x2, f(u) = u, and f(v)=xu then f (A) = K[x2] + K[x2]u + K[x2]xu. Received by the editors October 23, 1989. 1980 Mathematics Subject Classification (1985 Revision). Primary 13A1 5, 13E1 5. (? 1990 American Mathematical Society 0002-9939/90 $1.00 + $.25 per page
The Correction of I and Q Errors in a Coherent Processor

A method is presented for correcting the gain and phase imbalances and the bias errors of the in-phase and quadrature channels of a coherent signal processor [1] by means of coefficients which are derived from measurements of a test signal. The residual errors after correction depend upon the signal-to-noise ratio (S/N) of the test signal and the degree of filtering used in deriving the correction coefficients.
ASSOCIATION OF MYXOVIRUS-LIKE PARTICLES WITH ACUTE LEUKAEMIA OF CHILDHOOD.

THE presence of virus-like particles in thin sections of material from mice and chickens with virus-induced leukaemias has been reported1–5. Particles of similar morphology have been observed in thin sections of human leukaemic tissue1,6 as well as in leukaemic plasma6–8. However, because of a lack of a suitable biological system, there is still no conclusive evidence that human leukaemia or any other human malignancy is virus-induced. We, therefore, feel that the application of physical methods, not only for recognition but also for quantitation of viruses, is especially valuable at this time. For this reason, part of our efforts in the investigation of acute leukaemia of childhood (see ref. 9 for details of study design and tissue culture findings) are being directed toward applying recently developed electron microscopic methods for the staining and counting of virus particles10–12. We have avoided the use of thin-sectioning methods because of their poor sensitivity in revealing low concentrations of virus and the difficulties associated with interpreting the results quantitatively. The results of investigations of sera and heparinized plasma from children with acute leukaemia, from healthy children, and from normal adults are reported here. The purpose of the work was not only to search for particles with internal structure, but also to determine quantitatively the number of particles with limiting membranes having the size and general appearance of myxoviruses.
Reactions of fluorinated cyclobutenes with grignard reagents

Abstract The reaction of an alkylmagnesium bromide with perfluorocyclobutene has been found to favor the formation of a vinylic monoalkyl product whereas an alkylmagnesium chloride favored the synthesis of a vinylic dialkyl compound. Increased branching at the α- or β-carbon of the isomeric butyl Grignard reagents caused a shift to the vinylic monoalkyl product and to reduced yields, especially with increased α-branching. Unsymmetrical vinylic dialkylperfluorocyclobutenes are reported for the first time.
Do Living Wage Policies Diffuse

This research note examines the conditions under which large U.S. cities pass living wage laws. It updates the only published article on the subject with new data and improved analytic methods. First, it shows that poverty, privatization, and the density of community organizations are associated with policy passage. Second, it provides new quantitative evidence that the living wage movement is, in part, a diffusion process associated with national community-organizing networks.
Protective immunity against feline immunodeficiency virus induced by inoculation with vif-deleted proviral DNA.

To determine whether live-attenuated feline immunodeficiency virus (FIV) proviral DNA will induce protective immunity, a plasmid clone constructed with a FIV provirus containing a deletion in the viral accessory gene vif (FIV-pPPR-Deltavif) was inoculated as proviral DNA into four cats by the intramuscular route. After 43 weeks, these cats were boosted with the same proviral plasmid. Analysis of peripheral blood mononuclear cells at several time points after the primary and booster inoculations revealed no detectable virus or proviral DNA. At 6 weeks after the booster, immunized cats and additional naive control cats were challenged with a cell-free preparation of the infectious biological isolate FIV-PPR by the intraperitoneal route. Virus was detected after challenge in unvaccinated control cats but not in any of the FIV-pPPR-Deltavif-immunized cats. Both FIV Gag- and Env-specific cytotoxic T lymphocyte (CTL) activities were detected in peripheral blood cells of control cats after challenge infection, whereas only one of four cats immunized with FIV-pPPR-Deltavif DNA exhibited a measurable CTL response to Env following challenge. Although anti-Gag antibodies were not detected after both proviral DNA inoculation and challenge, anti-Env antibodies were found in FIV-pPPR-Deltavif-immunized cats after vaccination as well as after challenge. These findings indicate that inoculation with FIV-pPPR-Deltavif proviral DNA induced resistance to challenge with infectious FIV and that a vif deletion mutant may provide a relatively safe attenuated lentiviral vaccine.
Transcranial radiographs in the evaluation of craniomandibular (TMJ) disorders

To use a radiographic technique to evaluate patients, one must be aware of the limitations of the study. A TR can be used to show both structural and positional changes of the lateral third of the condyle and fossa. TR obtained at vertical angulations greater than 20 degrees will add significant distortion to the full open-mouth radiograph. The structural changes seen in the joints of patients with the TR who had further diagnostic studies were confirmed with tomography. The changes seen with tomography were either as severe or more extensive than those noted on the TR. Three patients who had extensive structural changes on both the condyle and fossa were shown by arthrography to have a perforation in the joint's soft tissues. While the lateral position of the condyle does not represent the entire joint, this study has shown that it may qualitatively serve as a positional indicator for the joint. The TR together with the rest of a patient's examination data can be used in the treatment. For the patient who has not responded to therapy or whose TR disagrees with the clinical examination, tomographic and arthrotomographic studies are suggested. In the group of 61 patients, 11 (18%) fell into this category. Further diagnostic studies were not felt to be necessary for the remaining 50 patients.
Photoelectron holography for high-resolution spectromicroscopy

Abstract X-ray photoelectron spectromicroscopy seeks to couple high spatial resolution with a contrast mechanism derived from the photoelectron binding-energy chemical shift. The two major approaches to direct surface imaging with photoelectrons are based either on using a focused incident X-ray beam which is scanned over the sample, or on electron optical techniques which form a magnified image of the surface using the emitted electrons. Due to practical problems and optical aberrations, both approaches appear to have an ultimate spatial resolution limit in the range of 10 nm. An alternative approach to mapping the locations of atoms in specific chemical states is X-ray photoelectron holography, which has the possibility for producing maps of the positions of photoemitting atoms with atomic resolution. Advantages and limitations of this new technique for emission spectromicroscopy are discussed.
High-performance midinfrared quantum cascade lasers

The design and operating principles of quantum cascade lasers (QCLs) are reviewed along with recent developments in high-power cw and broadband devices. Cw power levels of several watts at room temperature have been achieved at 4.6-µm wavelength; broadband single-mode tuning (400 cm−1) has been achieved using an external-cavity QCL with a grating as a tuning element. An alternative approach, consisting of a monolithically integrated array of single-mode QCLs individually current-driven by a microcontroller, has led to broadband single-mode tuning over a range of 200 cm−1 without requiring the use of moving parts. This spectrometer on a chip holds promise for high-brightness compact trace-gas sensors capable of operating in harsh environments.
Estimates of the emission rates of ammonia from light-duty vehicles using standard chassis dynamometer test cycles

Abstract Emissions rates of ammonia (NH 3 ) are reported for a fleet of 39 in-use light-duty gasoline-fueled vehicles. The fleet consisted of both light-duty passenger vehicles and light-duty trucks with various levels of emission control technologies, ranging from non-catalyst vehicles to those that were certified at the ULEV standard for California. NH 3 measurements were performed using Fourier transform infrared spectroscopy and the federal test procedure (FTP) driving cycle. The FTP NH 3 emission rate for this fleet of vehicles averaged 54 mg mi −1 with a range from −1 . For this fleet of vehicles, NH 3 emissions did not decline as significantly as the regulated pollutants with improvements in emission control technology. A subset of 5 vehicles was tested over the US06, the New York City Cycle (NYCC), and a high-speed freeway cycle for comparison with the FTP cycle. NH 3 emissions showed a strong cycle dependence, with increased emissions under more aggressive driving conditions. These results show that NH 3 emissions formed during more aggressive driving conditions should be considered in the development of NH 3 emission factors. The onset of NH 3 emissions typically occurred after catalyst light-off, near when the catalyst reached its equilibrium temperature. Initial studies showed that NH 3 emissions increased as the sulfur content in the fuel was decreased.
Sequence homology between yeast histone H3 and uveitopathogenic site of S-antigen: lymphocyte cross-reaction and adoptive transfer of the disease.

Abstract Experimental autoimmune uveitis (EAU) serves as an animal model of ocular inflammation. The disease is caused by the immunization of microgram amounts of a soluble retinal protein, designated S-antigen, in susceptible animal strains, including primates. We induced EAU and experimental autoimmune pinealitis (EAP) in Lewis rats with a small synthetic peptide corresponding to amino acid positions 106–121 in yeast histone H3. This peptide contains five consecutive amino acids identical to a uveitopathogenic site (peptide M) in human S-antigen. Lymph node or mononuclear cells from different species of animals immunized either with histone H3 or with peptide M showed significant cross-reaction as measured by in vitro lymphocyte mitogenesis assay using [ 3 H]thymidine. Also, we adoptively transferred the EAU and EAP in naive rats by immune lymph node cells. These findings support the fact that selected bacterial, viral, or fungal proteins with amino acid sequence homologies to normal retinal proteins are uveitopathogenic and, as such, provide a basis for autoimmune inflammatory diseases.
Autonomous Recording of Great Gray Owls in the Sierra Nevada

Abstract The Great Gray Owl (Strix nebulosa) is a difficult species to detect because of its remote breeding locations and secretive nature. We used autonomous recording units (ARUs) to monitor nest activity at 6 Great Gray Owl territories from June–July 2006 in the Sierra Nevada, California. We also used ARUs to survey for Great Gray Owl presence–absence status at 15 potential territories from March–April 2007. Each unit recorded 12 h/night (18:00–06:00). In 2006, we recorded juvenile begging calls at 3 sites. In 2007, we recorded adult Great Gray Owl vocalizations at 10 sites. We recorded audible calls during approximately 40% of the nights sampled at locations with owl detections. We concluded that a combination of ARUs and acoustic analysis provides an effective non-invasive method to detect and monitor Great Gray Owls as well as other secretive and nocturnal species.
The synthesis and characterization of aliphatic sulfonic acid cation exchangers for HPLC

Two oxidation procedures for the synthesis of silicabased aliphatic sulfonic acid cation-exchangers for HPLC are described. Several reaction conditions for oxidizing a terminal-bonded thiol with organic peroxides are provided along with their yields, capacities, reproducibility, and chromatographic behavior. Also, three methods for determining exchange capacity are discussed, and their relationship to the capacity factors of charged solutes is compared. The maximum capacity determined by the titration of the bonded silica was 0.34 meq/gram. The general problems of synthesizing cation-exchangers, measuring their efficiencies and exchange capacities, and evaluating their overall performances are outlined.
Ecology: Return of the niche

Two ideas vie for prominence in community ecology — 'niche partitioning' and 'neutral theory'. A survey of patterns of tree abundance in tropical forest prompts fresh thinking on their respective effects.
Genuine medicine?: Why safeguarding the pharmaceutical supply chain from counterfeit drugs with RFID is vital for protecting public health and the health of the pharmaceutical industry

Purpose – This paper seeks to investigate the fast‐growing problem of counterfeit prescription drugs and the steps being taken by both the private and public sectors to counteract it. Design/methodology/approach – The author documents both the size and scope of the counterfeit pharmaceutical problem in the USA. The paper also looks at the steps being taken by pharmaceutical manufacturers and wholesalers, as well as legal efforts being undertaken by federal and state governments, to counteract the growing concerns over fake medicines being introduced into the pharmaceutical supply chain. Findings – The paper builds the business case for radio frequency identification (RFID) technology to be employed to track pharmaceuticals in the supply chain and counter the growing threat of counterfeit drugs. Research limitations/implications – The principal limitation of this research is that it is being conducted on both a rapidly evolving problem (counterfeit pharmaceuticals) and the use of a rapidly developing technology (RFID) to counteract it. Thus, in time, the parameters of both the counterfeit drug problem and the technological solutions to it may shift dramatically. Practical implications – The paper demonstrates that RFID provides the only effective method of providing “track and trace” electronic pedigrees for prescription drugs. Originality/value – The paper is a valuable overview of the problems associated with the vulnerability of the pharmaceutical supply chain in the USA and the potential cost‐effective, life‐saving use of RFID to better secure prescription drugs, both in transit and in inventory.
Isolation by sucrose-density fractionation and cultivation in vitro of actinomycetes from nitrogen-fixing root nodules

The fixation of atmospheric nitrogen by actinomycete-nodulated, woody dicotyledonous plants represents a substantial contribution to the global nitrogen cycle1, contributing especially to forested areas, wetlands, fields and disturbed sites of temperate and tropical regions2. The study of these nitrogen-fixing symbioses has been hampered by difficulties in isolating and culturing the microsymbionts in vitro. Recently, root nodule actinomycetes have been isolated by microdissection techniques and cultured in vitro3,4. We report here the isolation and culture for the first time of the actinomycetes associated with root nodules of Elaeagnus umbellata (Elaeagnaceae) and Alnus viridis ssp. crispa (Betulaceae) (shown in Fig. 1a and b, respectively), using a technique radically different from those used previously. For separating actinomycetes from root nodules, we have used the simple fractionation technique of sucrose-density sedimentation.
Computational Models of Emergent Properties

Computational models fail to shed light on general metaphysical questions concerning the nature of emergence. At the same time, they may provide plausible explanations of particular cases of emergence. This paper outlines the kinds of modest explanations to which computational models are suited.
Quantification and localization of ornithine decarboxylase in the embryonic palate

Ornithine decarboxylase (ODC; EC4.1.1.17), the key enzyme in polyamine biosynthesis, and intracellular polyamines increase rapidly and markedly in tissues and cells that are actively proliferating as well as differentiating and decrease as these processes cease. ODC activity has also been implicated as playing a role in the proliferation and differentiation of cells derived from the developing palate. Ornithine decarboxylase activity was thus quantified and ODC localized in the developing murine palate in vivo. Levels of ODC activity showed little variation during the ontogeny of the palate, averaging 126 pmol CO2/mg protein/hr. When difluoromethylornithine (DFMO), an irreversible inhibitor of ODC activity, was administered to pregnant mice throughout the period of palate development (days 11-14), palatal tissue ODC activity was reduced by 85%. No craniofacial malformations were observed, however. The lack of a teratogenic effect by DFMO treatment could be due to sufficient remaining ODC activity in craniofacial tissue and/or maintenance of intracellular polyamine levels by the activity of a polyamine transport system. The activity of this system was demonstrated by the ability of palatal tissue in vivo to take up radiolabeled putrescine. The presence of a polyamine transport system was previously suggested by the demonstration of such a system in palate mesenchymal cells in vitro. Dramatic temporal and spatial shifts in tissue patterns of immunolocalization for ODC in developing palatal tissue were also seen. Immunostaining for ODC was evenly distributed in oral, nasal, and medial edge palate epithelial cells on day 12 of gestation. The basal aspects of epithelial cells were, however, more intensely stained. Mesenchymal cells exhibited a peri-nuclear immunostaining pattern. On days 12 and 13 of gestation, the staining patterns for ODC in palate epithelial and mesenchymal cells were comparable. On day 14 of gestation, all regions of the palate epithelium, particularly the medial edge epithelia, were immunostained for ODC, whereas the intensity of staining in the mesenchymal cells was significantly reduced. This study represents essential initial observations toward understanding the role that ODC may play in normal craniofacial development.
Robust spatial navigation in a robot inspired by chemotaxis in caenorhabditis elegans

We report on the design and implementation of an autonomous robot that performs phototaxis under the control of a simulated neural network. The mechanical configuration of the robot and its neural network controller are patterned after those believed to produce chemotaxis in the nematode Caenorhabditis elegans. The network is first optimized to produce phototaxis in a simulated, nematode-like robot and then is tested on a real robot. We find that both the simulated and real robot perform reliably, making nearly identical trajectories for similar environments and similar starting conditions. Furthermore, their performance is robust to significant perturbations of the robot's locomotion parameters. Finally, we discuss the implicit computational rule that this network uses to control phototaxis. This makes the results intuitive and improves our intuition about control of tactic behavior in two dimensions.
Map-based analysis of genetic loci on chromosome 2D that affect glume tenacity and threshability, components of the free-threshing habit in common wheat (Triticum aestivum L.)

During the domestication of bread wheat (Triticum aestivum L.), evolutionary modifications that took place in seed dispersal mechanisms enhanced its suitability for agricultural production. One of these modifications involved the evolution of the free-threshing or hulless characteristic. In this study, we studied quantitative trait loci (QTL) affecting components of the free-threshing habit (threshability and glume tenacity) on chromosome 2D in a recombinant inbred line (RIL) population developed by the International Triticeae Mapping Initiative (ITMI) as well as the tenacious glumes 1 (Tg1) gene in F2 progeny (CS/CS2D F2) of a cross between Chinese Spring and the 2D2 substitution line [Chinese Spring (Ae.tauschii 2D)]. In the ITMI population, two QTL affected threshability (QFt.orst-2D.1 and QFt.orst-2D.2) and their location coincided with QTL affecting glume tenacity (QGt.orst-2D.1 and QGt.orst-2D.2). In the CS/CS2D F2 population, the location of QTL that affected glume tenacity (QGt.orst-2D.1), the size of a glume base scar after detachment (QGba.orst-2D), and Tg1 (12-cM interval between Xwmc112 and Xbarc168) also coincided. Map comparisons suggest that QFt-orst-2D.1, QGt.orst-2D.1, and QGba.orst-2D correspond to Tg1 whereas QFt.orst-2D.2 and QGt.orst-2D.2 appear to represent separate loci. The observation of coincident QTL for threshability and glume tenacity suggests that threshability is a function of glume adherence. In addition, the observation of the coincident locations of Tg1 and QTL for the force required to detach a glume and the size of a glume base scar after detachment suggests that Tg1’s effect on both glume tenacity and threshability resides on its ability to alter the level of physical attachment of glumes to the rachilla of a spikelet.
Single-walled carbon nanotubes as excitonic optical wires

Although metallic nanostructures are useful for nanoscale optics, all of their key optical properties are determined by their geometry. This makes it difficult to adjust these properties independently, and can restrict applications. Here we use the absolute intensity of Rayleigh scattering to show that single-walled carbon nanotubes can form ideal optical wires. The spatial distribution of the radiation scattered by the nanotubes is determined by their shape, but the intensity and spectrum of the scattered radiation are determined by exciton dynamics, quantum-dot-like optical resonances and other intrinsic properties. Moreover, the nanotubes display a uniform peak optical conductivity of ~8 e^2/h, which we derive using an exciton model, suggesting universal behaviour similar to that observed in nanotube conductance. We further demonstrate a radiative coupling between two distant nanotubes, with potential applications in metamaterials and optical antennas.
Implementation of Polymerase Chain Reaction to Rule Out Clostridium difficile Infection Is Associated With Reduced Empiric Antibiotic Duration of Therapy.

PurposeThe polymerase chain reaction (PCR) test has higher sensitivity and a faster turnaround time than the enzyme immunoassay (EIA) for identification of Clostridium difficile, although the clini...
Imaging spectrum of renal oncocytomas: a pictorial review with pathologic correlation

The purpose of this pictorial review is to present the imaging spectrum of renal oncocytomas with radiological-pathological correlation. The differences in tumour cellularity (high cellularity or low cellularity with abundant stroma) and haemorrhagic/cystic change contribute to a wide spectrum of imaging findings of renal oncocytomas. Imaging findings substantially overlap those of common subtypes of clear cell and non-clear cell renal cell carcinomas. Multifocal renal oncocytomas are not rare, and making the diagnosis of oncocytoma with concomitant renal cell carcinoma is difficult. In addition, renal oncocytomas that demonstrate interval growth or develop in the setting of end-stage renal disease may be mistaken for malignancy. • High cellular components demonstrate avid arterial enhancement and subsequent washout. • Low cellular components demonstrate gradual subsequent enhancement owing to abundant stroma. • Cystic and hemorrhagic changes may account for lesion heterogeneity in the delayed phase. • Multifocal oncocytomas and oncocytomas coexisting with renal cell carcinoma are not rare. • Renal oncocytomas may demonstrate interval growth.
Effects of weaning and ionophore supplementation on selected blood metabolites and growth in dairy calves.

Abstract Dairy calf weaning results in blood ketone concentrations in excess of mature rates of use and can result in excretion of ketones in urine representing a loss of energy. Lasalocid is frequently supplemented as an anticoccidial agent in calf starters; however, in mature ruminants it is known to alter molar ratios of ruminal volatile fatty acids (VFA). Effects of weaning transition and postweaning ionophore supplementation on body weight, dry matter (DM) intake, average daily gain (ADG), and blood concentrations of glucose, acetoacetate, β -hydroxybutyrate (BHBA), lactate, pyruvate, nonesterified fatty acids (NEFA), VFA, insulin, and glucagon were examined using Jersey bull calves (n=24) over 16 wk. Calves were blocked into groups of 2 according to birth date and weight and randomly assigned to receive either a commercial pelleted starter (control), or the same diet containing lasalocid (TRT; 83mg/kg of DM). Calves were fed milk replacer from d 3 to 34 (d 3 to 20=454g/d at 12% solids; d 21 to 34=568g/d at 15% solids), from d 35 to 48 calves received both replacer (d 35 to 41=454g/d; d 42 to 38=227g/d) and free access to control or TRT starter, and from d 49 to 112 received ad libitum control or TRT. Body weight and jugular blood metabolite concentrations were measured and recorded weekly. Postweaning DM intake, average daily gain, and feed:gain did not differ between control and TRT calves. Glucose and NEFA concentrations did not differ between control and TRT, but declined with age. Insulin and glucagon concentrations did not differ between control and TRT, but glucagon concentrations increased with weaning. Total VFA significantly increased following introduction of solid feed at d 35 in both groups with an apparent 1-wk lag in TRT VFA increases compared with control. Jugular acetate and butyrate concentrations were greater in control calves than TRT calves during wk 7. Propionate concentrations did not differ between control and TRT at any time following weaning. Blood BHBA concentrations were greater in control than TRT during wk 8 and 9. Thus, consumption of starter supplemented with lasalocid delayed peak acetate and butyrate and lowered peak BHBA concentrations. However, supplementation at concentrations currently recommended for control of coccidiosis did not appear to be sufficient to enhance growth or efficiency during the wk 7 to 16 postweaning interval for this sample size.
PMR1, a Ca2+-ATPase in Yeast Golgi, Has Properties Distinct from Sarco/endoplasmic Reticulum and Plasma Membrane Calcium Pumps

PMR1, a P-type ATPase cloned from the yeast Saccharomyces cerevisiae, was previously localized to the Golgi, and shown to be required for normal secretory processes (Antebi, A., and Fink, G.R. (1992) Mol. Biol. Cell 3, 633-654). We provide biochemical evidence that PMR1 is a Ca2+-transporting ATPase in the Golgi, a hitherto unusual location for a Ca2+ pump. As a starting point for structure-function analysis using a mutagenic approach, we used the strong and inducible heat shock promoter to direct high level expression of PMR1 from a multicopy plasmid. Yeast lysates were separated on sucrose density gradients, and fractions assayed for organellar markers. PMR1 is found in fractions containing the Golgi marker guanosine diphosphatase, and is associated with an ATP-dependent, protonophore-insensitive 45Ca2+ uptake activity. This activity is virtually abolished in the absence of the expression plasmid. Furthermore, replacement of the active site aspartate within the phosphorylation domain had the expected effect of abolishing Ca2+ transport activity entirely. Interestingly, the mutant enzymes (Asp-371 --> Glu and Asp-371 --> Asn) demonstrated proper targeting to the Golgi, unlike analogous mutations in the related yeast H+-ATPase. Detailed characterization of calcium transport by PMR1 showed that sensitivity to inhibitors (vanadate, thapsigargin, and cyclopiazonic acid) and affinity for substrates (MgATP and Ca2+) were different from the previously characterized sarco/endoplasmic reticulum and plasma membrane Ca2+-ATPases. PMR1 therefore represents a new and distinct P-type Ca2+-ATPase. Because close homologs of PMR1 have been cloned from rat and other organisms, we suggest that Ca2+-ATPases in the Golgi will form a discrete subgroup that are important for functioning of the secretory pathway.
RNA synthesis in the ovary and oocytes of the starfish.

Abstract Qualitative studies on the in vitro uptake and incorporation of tritiated uridine into RNA of the somatic and germinal elements of the starfish ovary were carried out prior to and during hormone-induced oocyte maturation and spawning. Autoradiography of nonhormone-treated ovaries indicated that the outer ovarian wall contained the highest concentration of label, with lesser amounts in the follicle cells and least in the oocytes. Oocytes and follicle cells localized at the periphery of the ovary were labeled first, and both cells became progressively labeled throughout the ovary with time; the label first appeared localized in the nucleolus of the oocyte. Sucrose gradient analysis of the separated cellular components of prelabeled hormone-treated ovaries indicated that RNA synthesis occurred in all segments of the ovary and that the spawned oocyte fraction was the least active. Synthesis of ribosomal RNA was detectable after a lag period of approximately 4 hr. Oocytes incubated in 3 H-uridine during and subsequent to 1-methyladenine-induced spawning and maturation synthesized 15–19 S and low molecular weight RNA but not ribosomal RNA. Synthesis of the 15–19 S RNA was inhibited with ethidium bromide and to a limited extent by actinomycin D. Isolated mitochondrial fractions contained most of the labeled 15–19 S RNA. These data suggest the mitochondrial origin of most, if not all, of this intermediate-weight RNA. On the basis of these studies, it appears that starfish oocytes and follicle cells are metabolically active at the transitional period from growth to maturational stages in oocytes. Synthesis of RNA furthermore apparently continues in the cytoplasm subsequent to germinal vesicle breakdown and spawning.
Environmental scanning electron microscopy investigations of biodeterioration

Case studies will be presented in which environmental scanning electron microscopy (ESEM) has been used to provide unique insight into the role of microorganisms in deterioration processes. ESEM is an excellent tool for demonstrating spatial relationships between microorganisms and substrata because hydrated, nonconducting samples can be viewed with a minimum of manipulation. Copper and iron-rich deposits associated with bacteria were detected within corrosion layers on copper and steel surfaces, respectively. Fungal mycelia growing on wooden storage spools were shown to penetrate protective grease on carbon steel wire rope in contact with the spool and to cause localized corrosion. Large numbers of marine bacteria were documented within paint blisters and disbonded regions of fiber-reinforced polymeric composites. In both cases, it appears that microbial gas production resulted in mechanical damage to the substrata.
Beam Position Monitor Readout and Control in the SLC Linac

A beam position monitoring system has been implemented in the first third of the SLC linac which provides a complete scan of the trajectory on a single beam pulse. The data is collected from the local micro-computers and viewed with an updating display at a console or passed on to application programs. The system must operate with interlaced beams so the scans are also interlaced, providing each user with the ability to select the beam, the update rate, and the attenuation level in the digitizing hardware. In addition each user calibrates the hardware for his beam. A description of the system architecture will be presented.
EFFECT OF POLYMER MOLECULAR WEIGHT, SOLVENT AND CASTING SOLUTION COMPOSITION ON THE PORE SIZE AND THE PORE SIZE DISTRIBUTION OF POLYETHERSULFONE (VICTREX) MEMBRANE

The effect of the molecular weight of polyethersulfone (Victrex) polymers, the nature of the solvent and the polymer concentration on the effective hydrodynamic radius of polymer in the membrane casting solution was investigated. The membranes were prepared from the casting solutions studied above and ultrafiltration experiments were performed with polyethylene glycol solutes. The average pore sizes and the pore size distributions on the membrane surfaces were further calculated from the ultrafiltration performance data obtained above. Strong correlations were found between the effective hydrodynamic radius of the polymer in the casting solution and the average pore size on the membrane surface. The mechanism of the pore formation was proposed on the basis of the polymer size—pore size correlation.
Use of low-temperature thermal alkylation to eliminate ink migration in microcontact printed patterns.

We demonstrate aqueous hydrogel-based microcontact printing of amine ligands into solvent-templated nanocavities of chloromethylphenyl-based siloxane or thin polymer films. Migration of pyridine ligands within films following printing, which can compromise pattern fidelity, is eliminated by heat treatment of the substrate. Gentle heating (e.g., 50 degrees C, 5 min) leads to the efficient alkylation of mobile pyridine adsorbate by the C-Cl bonds of the film, covalently tethering the adsorbate to the surface as a pyridinium salt. Subsequent binding of a Pd-based colloid to surface pyridinium (and remaining strongly bound and immobile pyridine ligand) sites permits selective electroless metal deposition and fabrication of patterned metal films.
To See Is Not to Own: Child Study as a Practice of Attention for Beginning Teachers.

Prospective teachers are often found to have difficulty focusing their attention on students in sustained and constructive ways. Instead, in what is sometimes understood as a developmental matter, beginners may seem highly concerned with their own feelings and needs. This article offers a contrary finding. It examines two cases of prospective teachers' provision of sustained, generative attention not to self, but to other—to the child. An enabling structure appears to be “Child Study.” Drawing on Dewey and Benjamin, the “aesthetic impulse” is offered as an analytic construct useful in understanding how this pedagogical focus on the other may be elicited.
Cancer and aging: the importance of telomeres in genome maintenance.

Telomeres are the specialized DNA-protein structures that cap the ends of linear chromosomes, thereby protecting them from degradation and fusion by cellular DNA repair processes. In vertebrate cells, telomeres consist of several kilobase pairs of DNA having the sequence TTAGGG, a few hundred base pairs of single-stranded DNA at the 3' end of the telomeric DNA tract, and a host of proteins that organize the telomeric double and single stranded DNA into a protective structure. Functional telomeres are essential for maintaining the integrity and stability of genomes. When combined with loss of cell cycle checkpoint controls, telomere dysfunction can lead to genomic instability, a common cause and hallmark of cancer. Consequently, normal mammalian cells respond to dysfunctional telomeres by undergoing apoptosis (programmed cell death) or cellular senescence (permanent cell cycle arrest), two cellular tumor suppressor mechanisms. These tumor suppressor mechanisms are potent suppressors of cancer, but recent evidence suggests that they can antagonistically also contribute to aging phenotypes. Here, we review what is known about the structure and function of telomeres in mammalian cells, particularly human cells, and how telomere dysfunction may arise and contribute to cancer and aging phenotypes.
Distributed multipath routing for data center networks based on stochastic traffic modeling

Modern data center networks often adopt multipath topologies for greater bisection bandwidth and better fault tolerance. However, traditional distributed routing algorithms make routing decisions based on only packet destinations, and cannot readily utilize the multipath feature. In this paper, we study distributed multipath routing for data center networks. First, to capture the time varying and non-deterministic nature of data center network traffic, we present a stochastic traffic model based on the log normal distribution. Then, we formulate the stochastic load-balanced multipath routing problem, and prove that it is NP hard for typical data center network topologies, including the fat tree, VL2, DCell, and BCube. Next, we propose our distributed multipath routing algorithm, which balances traffic among multiple links by minimizing the probability of each link to face congestion. Finally, we implement the proposed algorithm in the NS2 simulator, and provide simulation results to demonstrate the effectiveness of our design.
Influence of micelles and microemulsions on one-electron reduction of 1-alkyl-4-carbomethoxypyridinium ions

Abstract Diffusion, heterogeneous kinetics, and radical stability were studied for one-electron reductions of 1-methyl- and 1-hexadecyl-4-carbomethoxypyridinium ions at glassy carbon electrodes. Results were compared in ionic micelles, bicontinuous microemulsions, and isotropic acetonitrile. The 1-methyl derivative binds to the surface of SDS micelles, but not to CTAB micelles. Only small voltammetric peaks were found for the 1-hexadecyl derivative in CTAB micelles and none were observed in SDS micelles. Outside of this case, heterogeneous electron transfer was not greatly influenced by the surfactant media. In bicontinuous microemulsions of didodecyldimethylammonium bromide, water, and dodecane or tetradecane, the 1-hexadecyl derivative was a reasonably good probe for chemical environment and diffusion at oil-water interfaces. Instability of 1-methyl-4-carbomethoxypyridyl radical in microemulsions is consistent with protonation of the radical in the water phase. 1-Methyl and 1-hexadecyl-4-carbomethoxypyridyl radicals were stable in all other media studied.
Defining characteristics of Tn5 Transposase non-specific DNA binding

While non-specific DNA plays a role in target localization for many recombinases, transcription factors and restriction enzymes, the importance of non-specific DNA interactions for transposases has not been investigated. Here, we discuss non-specific DNA-Tn5 Transposase (Tnp) interactions and suggest how they stabilize the Tnp and modulate Tnp localization of the 19 bp Tnp recognition end sequences (ESes). DNA protection assays indicate that full-length Tnp interacts efficiently with supercoiled DNA that does not contain ESes. These interactions significantly prolong the lifetime of Tnp, in vitro. The balance between non-specific DNA bound and free Tnp is affected by DNA topology, yet, intermolecular transfer of active Tnp occurs with both supercoiled and linear non-specific DNA. Experiments with substrates of varying lengths show that Tn5 Tnp can utilize non-specific DNA to facilitate localization of an intramolecular ES over distances less than 464 bp. Finally, synaptic complex formation is inhibited in the presence of increasing concentrations of supercoiled and linear pUC19. These experiments strongly suggest that Tn5 Tnp has a robust non-specific DNA binding activity, that non-specific DNA modulates ES sequence localization within the global DNA, most likely through a direct transfer mechanism, and that non-specific DNA binding may play a role in the cis bias manifested by Tn5 transposition.
Platinum(II) Complexes Bearing 2‐(9,9‐Dihexadecyl‐7‐R‐fluoren‐2‐yl)‐1,10‐phenanthroline Ligands: Synthesis, Photophysics and Reverse Saturable Absorption

Six platinum(II) complexes bearing 2-(9,9-dihexadecyl-7-R-fluoren-2-yl)-1,10-phenanthroline ligands (R = NO2, CN, I, H, benzothiazole, thiophene for ligands 1–6, respectively) were synthesized and their photophysics and reverse saturable absorption (RSA) were systematically investigated. All complexes exhibit intense absorption bands between 350 and 450 nm, which are attributed to 1π,π*/1ILCT (intraligand charge transfer) transitions, and broad 1MLCT (metal to ligand charge transfer) transitions between 475 and 550 nm. All complexes are emissive at room temperature in a variety of solvents and at 77 K in butyronitrile glassy matrix, with the long-lived, structured emission appearing between 600 and 750 nm. The emitting states are assigned to predominantly the 3π,π* state with an admixture of 3MLCT characters. Upon ns laser excitation at 355 nm, all complexes display broad, moderately strong transient absorption from the visible to the near-IR region. As a result, RSA is observed from all complexes at 532 nm for ns laser pulses. The strength of the RSA for these complexes follows the trend: Pt-2 > Pt-3 > Pt-4 > Pt-1 >> Pt-5 > Pt-6, which correlates well with the trend of the estimated ΦTσex/σ0 values (where ΦT is the triplet excited state quantum yield, and σex and σ0 are the excited-state and ground-state absorption cross-section, respectively) at 532 nm. It is revealed that substitution at the 7-position of the fluorenyl component exerts a distinct effect on the photophysics and RSA of the complexes. Aromatic substituents such as benzothiazol-2-yl and 2-thionyl cause pronounced red-shifts of the absorption bands, the emission bands, and the transient difference absorption bands, but a decrease of the RSA at 532 nm.