cssi/SciSciGPT-SciSciNet huggingface dataset:
SWEET-FIX: A Quality Improvement Initiative for Hospitalized Stroke Patients With Undiagnosed Diabetes or Prediabetes

Abstract:The consequences of type-2 diabetes can be devastating and include a high risk for incident stroke. Fortunately, appropriate and timely treatment of diabetes may avert future complications and improve clinical outcomes. However, it would appear that up to 25% of the general population in th
Expression of myc-family, myc-interacting, and myc-target Genes During Preimplantation Mouse Development

Previous studies indicated that members of the myc gene family may be essential for preimplantation development. Other studies revealed that preimplantation embryos lacking c-myc, N-myc, or L-myc are viable, indicating that these genes are either not essential for preimplantation development or can be substituted for functionally by other myc gene family members. To investigate the possible role of these genes during preimplantation development, we determined the temporal patterns of expression of four members of the myc gene family, genes encoding myc-associated proteins, and four putative MYC target genes. We observed a sequential pattern of myc gene expression, with the L-myc mRNA expressed as a maternal transcript, the c-myc mRNA expressed during the 4-cell through morula stages, and the B-myc mRNA expressed highly at the morula and blastocysts stages. B-myc was the predominant family member expressed during preimplantation development. The mxi mRNA was not detectable and the mad mRNA was detectable only as a maternal transcript. The max mRNA, however, was expressed both as a maternal mRNA and as an embryonic message throughout most of preimplantation development. Three putative MYC target genes (Odc, cyclin E, and prothymosin-alpha) were transcriptionally induced during the 2-cell stage, and their mRNAs increased sharply in abundance during development to the morula and blastocyst stages. Another putative MYC target gene, cyclin A, was expressed both as a maternal mRNA and as an embryonic transcript. These data support the view that the expression of myc target genes may be supported initially through the expression of maternally inherited MYC proteins and corresponding mRNAs and that subsequent stage-specific changes in expression of myc genes, myc-associated genes, and myc target genes may control early differentiative events around the time of implantation.
Assessment of cognitive variables relevant to cognitive behavioral perspectives on anorexia nervosa and bulimia nervosa

Several cognitive behavioral writers have described cognitions regarding food, eating, and body weight as central to the psychopathology of anorexia and bulimia. However, only preliminary efforts have been undertaken to develop valid and reliable assessment methodologies for these cognitions. This paper reviews the current status of self-report questionnaires, thought-sampling procedures, and methods from cognitive psychology as applied to the assessment of eating disorder cognitions.
Proceedings of the tenth ACM SIGPLAN symposium on Principles and practice of parallel programming

These proceedings contain the papers presented at PPoPP'05, the ACM Symposium on Principles and Practice of Parallel Programming, held in Chicago, Illinois in June 2005.The program committee had a challenging task, with a tight reviewing schedule and a submission rate nearly double that of the previous conference. This reflects both the renewed interest in parallel computing and hard work by the PPoPP Publicity Chair, Rudi Eigenmann. The program committee selected 27 papers for presentation at the conference out of 87 papers submitted for review. Each paper was judged with respect to its originality, technical contribution, relevance, and presentation. There were good papers that we were unable to accept for presentation due to limitations in the conference schedule. The reviewers provided extensive comments on the papers and the final published version of each paper may differ, in some cases substantially, from the initial submission. The conference selection process does not constitute a complete review of the work. It is expected that many of the papers published in PPoPP'05 will be further revised and published in archival journals.
T lymphocytes can recognize determinants unique to neuropeptides of guinea pig myelin basic protein containing a single D‐isomer amino acid substitution

The present studies were undertaken to examine how the substitution of racemized forms of selected amino acids in synthetic peptides of guinea pig myelin basic protein (GPMBP) would alter the host's immunological ability to recognize such molecules. Using peptides from the 69-84 sequence of GPMBP containing a D-serine at position 70 or 75 (69-84[D-ser70 or D-ser75]) or D-aspartate at position 82 (69-84[D-asp82]), the findings demonstrated that the position of the diastereomer substitution on these neuropeptides was critical with respect to the ability of the immune system to recognize the molecule. Thus substitution of D-asp at position 82 or D-ser at position 75 abrogated the ability of these peptides to induce experimental autoimmune encephalitis and proliferation of host T cells. In contrast, a peptide containing a D-ser70 residue was capable of inducing clinical disease in rats, as well as stimulating T lymphocytes from 69-84-(D-ser70)-injected animals. Moreover, although this D-peptide was shown to share at least some determinant(s) with the 69-84 peptide, the use of 69-84(D-ser70)-stimulated cell lines demonstrated that some epitope(s) unique to this molecule could stimulate CD4+ syngeneic T cells.
Single Institutional Cost Analysis of 325 Robotic, Laparoscopic, and Open Partial Nephrectomies

Objective To compare costs associated with partial nephrectomy (PN) using robotic, laparoscopic (LPN), and open (OPN) approaches. Methods An Investigational Review Board-approved prospectively maintained database was reviewed for 325 patients who underwent PN at our institution from January 2009 to December 2010. Costs for each surgical technique were itemized, including hospitalization, operating room (OR), anesthesia, medication, laboratory and pathology, professional fees, and blood bank. Continuous variables were analyzed with Kruskal-Wallis and Wilcoxon tests, and categoric variables were analyzed with χ 2 and Fisher exact tests. Results Median costs of RPN were higher than LPN ($632, P = .005), but not significantly higher than OPN ($313, P = .14). The major cause of this difference was OR instrumentation and supplies. OR costs for LPN and OPN were equivalent ( P = .11). The cost associated with anesthesia was significantly lower for RPN and LPN than for OPN ( P = .002). RPN and LPN had lower hospitalization costs than OPN ( P P P P = .09 and P = .48, respectively). Conclusion RPN had higher operating room costs than LPN and OPN, primarily due to instrumentation and supplies. This higher cost was offset by decreased cost of hospitalization in compared with the OPN group. Modification of practices aimed at lowering RPN instrumentation and supply costs may enable cost equivalence.
Functional molecular size and structure of dextransucrase by radiation inactivation and gel electrophoresis.

Robyt et al. have proposed a mechanism for dextransucrase in which dextran is synthesized by the cooperative action of two equivalent nucleophiles (Robyt, J.F., Kimble, B.K. and Walseth, T.F. (1974) Arch. Biochem. Biophys. 165, 634-640). To distinguish between the possibilities that the enzyme is a monomer bearing both nucleophiles, or a dimer with each subunit bearing one nucleophile, the molecular weight of the enzyme was determined by SDS-polyacrylamide gel electrophoresis and by radiation inactivation. Two major forms of dextransucrase from Leuconostoc mesenteroides NRRL B-512F were found on SDS-polyacrylamide gel electrophoresis, with Mr 177 000 and 158 000, and sometimes a minor form with Mr 168 000. No form of dextransucrase smaller than Mr 158 000 was found, either in the presence or absence of dextran T10, although levansucrase was detected at Mr 92 000 and 116 000. On irradiation with 60Co, dextransucrase behaved as a single species with a maximum size of Mr 201 000. Because Mr 201 000 is much smaller than the minimum dimer size of Mr 316 000 (= 2 X 158 000), it is concluded that both nucleophiles are probably located on the same peptide, rather than one on each subunit of a dimer, and that peptide association is probably not required for dextran synthesis.
Simultaneous assessment of coronary stenosis, myocardial perfusion, and ventricular function in a patient with acute myocardial infarction

Cardiac CT angiography (CTA) is an ideal tool to investigate cardiac and noncardiac causes of acute chest pain. In this case, careful planning of the CTA acquisition and reconstruction limits permitted not only the exclusion of aortic dissection and provided high resolution images of coronary anatomy but also showed a concordant abnormality in myocardial perfusion and ventricular function in the setting of an acute coronary syndrome. Detailed planning of every CTA acquisition reconstruction protocol is essential to obtain the information necessary for clinical decision-making strategies and interventions in the patient with chest pain.
Strike It Lucky

Summary This article analyses the decision-making processes of contestants in a popular TV quiz show.
Does statin use affect the risk of developing prostate cancer

This commentary discusses the findings of Agalliu and colleagues, who performed a population-based, case–control study on the association between statin drugs and prostate cancer risk. Consistent with recent studies, statins were not associated with overall prostate cancer risk, but users had a possible lower risk of advanced disease. Obese men taking a statin had a higher risk of prostate cancer than those not taking a statin; however, a previously conducted, large, prospective, cohort study did not observe this association. This unexpected finding by Agalliu et al. could be a chance result, or could have arisen because of complex bias. Although statins might favorably affect men's prostate health, evidence is too limited to recommend statin use for the prevention of advanced prostate cancer. Consideration of the harms and benefits when prescribing a statin for vascular indications, including in obese men, should not presently include prostate cancer risk.
Quantitative real-time PCR for detection and identification of Candidatus Liberibacter species associated with citrus huanglongbing.

Abstract Citrus huanglongbing (HLB, ex greening) is one of the most serious diseases of citrus. Different forms of the disease are caused by different Candidatus Liberobacter species, Candidatus Liberibacter asiaticus (Las), Ca. L. africanus (Laf) and Ca. L. americanus (Lam). The pathogen is transmitted by psyllid insects and by budding with contaminated plant materials. The vector psyllid Diaphorina citri can transmit both Las and Lam. Establishment of this vector into Florida, reports of Lam and Las in Brazil in 2004, and recent confirmation of HLB in Florida in September 2005 is of great concern to the citrus industry. Research on HLB has been hampered by the unculturable nature of the causal bacterium in artificial media. It has also been difficult to detect and identify the pathogens, possibly because of low concentration and uneven distribution in host plants and vector psyllids. In this study, we developed quantitative TaqMan PCR using 16S rDNA-based TaqMan primer–probe sets specific to the different Ca. Liberobacter spp. An additional primer–probe set based on plant cytochrome oxidase (COX) was used as a positive internal control to assess the quality of the DNA extracts. The assays do not cross-react with other pathogens or endophytes commonly resident in citrus plants, and are very sensitive. HLB pathogen DNA was successfully amplified from the equivalent of 20 ng of midrib tissue from symptomatic leaves. The consistent results of the assays with DNA extracted from plants infected by various Ca. Liberibacter species grown in greenhouses and in the field demonstrated a degree of reproducibility for these TaqMan assays. Inhibitors of the PCR that are frequently present in plant extracts did not affect the assay results. The population of the pathogens was estimated to be 5 × 107 and 2 × 106 cells/g of fresh midribs of symptomatic sweet orange leaves infected by Las and Lam, respectively. The ratio of pathogen DNA to host plant DNA was estimated by to be 1:13,000 (w/w) and 1:1000 (c/c: target copy/target copy) in DNA extracts obtained by a standard CTAB method. Our rapid, sensitive and specific TaqMan PCR assay for the detection, identification and quantification of Ca. Liberibacter species has been successfully used in the confirmation of HLB caused by Las in Florida, and will be very useful for a broad range of research programs as well as the regulatory response and management of HLB disease.
Molecular Biology as a Tool for Taxonomy

Bacterial taxonomy based on phenotypic properties has encountered several problems: many organisms grow to poorly under laboratory conditions to be studied; the same phenotypic property often arises independently in more than one branch of a phylogenetic tree; and phenotypic schemes sometimes become unwieldy. Thus, molecular approaches have found a niche in taxonomy. Measurement of DNA hybridization between strains is the single most definitive tool for defining a species. Data on sequences of DNA and amino acids can be used to infer phylogeny. The molecular phylogenetic approach is most useful at levels ranging from kingdom to species. Restriction fragment length polymorphisms or variability in random polymerase chain reactions often differentiates strains. In the majority of cases, different molecular approaches tend to confirm established taxonomic schemes for bacteria. However, discrepancies between standard taxonomy and molecular data are not rare, especially when dealing with anaerobes. The contemporary approach to taxonomy takes into account both standard and molecular data.
Biochemistry: life imitates art.

The biosynthetic route to a naturally occurring insecticide, spinosyn A, has been established. One of the enzymes involved might catalyse a reaction that, although widely used by chemists, has proved elusive in nature. See Letter p.109 The naturally occurring compound spinosyn A is a component of several environmentally benign commercial insecticides. How its tetracyclic ring system is biosynthesized has been a subject of much speculation. One possible mechanism is the Diels–Alder reaction, a [4+2] cycloaddition reaction in which a cyclohexene ring is formed between a conjugated diene and an electron-deficient alkene via a single pericyclic transition state. This reaction is a rarity in nature, but a structural and kinetic study of the enzyme SpnF from the soil bacterium Saccharopolyspora spinosa now identifies it as perhaps the first stand-alone enzyme to merit the name 'Diels–Alderase', solely committed to the catalysis of a [4+2] cycloaddition reaction with an estimated 500-fold rate enhancement.
Differential Phosphorylation of a 57-kDa Protein Tyrosine Kinase During Egg Activation

Fertilization results in activation of many protein kinases which function during egg activation. We have used metabolic labelling and immunoprecipitation to study changes in the phosphorylation state of a 57-KDa src-family protein tyrosine kinase during fertilization of the sea urchin egg. The kinase was phosphorylated on serine at all periods studied but it was also phosphorylated transiently on tyrosine at 5 minutes post insemination and then on threonine at 90 minutes after fertilization. These data indicate that the 57-KDa PTK may be under complex regulatory control during the first cell cycle.
Thulium fiber laser lithotripsy using tapered fibers.

Introduction The Thulium fiber laser has recently been tested as a potential alternative to the Holmium:YAG laser for lithotripsy. This study explores use of a short taper for expanding the Thulium fiber laser beam at the distal tip of a small-core fiber. Methods Thulium fiber laser radiation with a wavelength of 1,908 nm, 10 Hz pulse rate, 70 mJ pulse energy, and 1-millisecond pulse duration was delivered through a 2-m-length fiber with 150-µm-core-input-end, 300-µm-core-output-end, and 5-mm-length taper, in contact with human uric acid (UA) and calcium oxalate monohydrate (COM) stones, ex vivo (n = 10 each). Stone mass loss, stone crater depths, fiber transmission losses, fiber burn-back, irrigation rates, and deflection through a flexible ureteroscope were measured for the tapered fiber and compared with conventional fibers. Results After delivery of 1,800 pulses through the tapered fiber, mass loss measured 12.7±2.6 mg for UA and 7.2±0.8 mg COM stones, comparable to conventional 100-µm-core fibers (12.6±2.5 mg for UA and 6.8±1.7 mg for COM stones). No transmission losses or burn-back occurred for the tapered fiber after 36,000 pulses, while a conventional 150-µm fiber experienced significant tip degradation after only 1,800 pulses. High irrigation rates were measured with the tapered fiber inserted through the working port of a flexible ureteroscope without hindering its deflection, mimicking that of a conventional 150 µm fiber. Conclusions The short tapered distal fiber tip allows expansion of the laser beam, resulting in decreased fiber tip damage compared to conventional small-core fibers, without compromising fiber bending, stone vaporization efficiency, or irrigation rates. Lasers Surg. Med. 42:45–50, 2010. © 2010 Wiley-Liss, Inc.
Role of Environmental Cues as Pavlovian-Conditioned Stimuli in Enhancement of Tolerance to Ethanol Effects: 1. Lethal Effects in Mice and Rats

Abstract Twice daily for 4 days, Swiss Webster of BALB/c mice were injected with 3.5 g/kg ethanol (20% w/v, IP) immediately after moving their home cages from the colony room to the experimental room. On day 5, half the mice were moved to the same room and the other half to a novel room with different lighting, acoustic, and olfactory stimuli. All mice were injected with ethanol overdoses ranging from 4.5–10.0 g/kg. LD 50 for ethanol increased following ethanol preexposure as compared to control ethanol-naive mice tested in the same experimental room. However, LD 50 was lower in both Swiss Webster and BALB/c mice tested in a novel environment than in the familiar environment. Novelty increased sensitivity to the effect of low and moderate but not the highest lethal doses of ethanol. This effect of novelty occured only in ethanol-experienced, but not ethanol-naive mice. In the following experiments, using a balanced design, Swiss Webster mice and Wistar rats were exposed to ethanol and saline alternatively in two distinct experimental rooms. On the final day, we found that there was no difference between animals tested in the room previously associated with administration of ethanol and animals tested in a saline-associated room in terms of LD 50 for ethanol. These results suggest that: a) Environmental stimuli do not play a role as Pavlovian conditioning stimuli in the development of tolerance to ethanol-induced lethality; and b) novelty acts as an unconditioned stimulus that increases ethanol's lethal effects by unspecific disruption of conditioned compensatory responses to internal conditioned stimuli, such as irritation of peritoneal cavity, smell, and taste of ethanol.
Ozone Temperature Correlations in the Upper Stratosphere as a Measure of Chlorine Content

We use data from the Nimbus-7 Limb Infrared Monitor of the Stratosphere (LIMS) for the 1978-1979 period together with data from the Upper Atmosphere Research Satellite Microwave Limb Sounder (UARS MLS) for the years 1993 to 1999, the Aura MLS for the years 2004 to 2011, and the Aura High Resolution Infrared Limb Sounder (HIRDLS) for the years 2005 to 2007 to examine ozone-temperature correlations in the upper stratosphere. Our model simulations indicate that the sensitivity coefficient of the ozone response to temperature (Delta ln(O3)/Delta.(l/T)) decreases as chlorine has increased in the stratosphere and should increase in the future as chlorine decreases. The data are in agreement with our simulation of the past. We also find that the sensitivity coefficient does not change in a constant-chlorine simulation. Thus the change in the sensitivity coefficient depends on the change in chlorine, but not on the change in greenhouse gases. We suggest that these and future data can be used to track the impact of chlorine added to the stratosphere and also to track the recovery of the stratosphere as chlorine is removed under the provisions of the Montreal Protocol.
Why does D2 bind better than H2? A theoretical and experimental study of the equilibrium isotope effect on H2 binding in a M(η2-H2) complex. Normal coordinate analysis of W(CO)3(PCy3)2(η2-H2)

Vibrational data (IR, Raman and inelastic neutron scattering) and a supporting normal coordinate analysis for the complex trans-W(CO)3(PCy3)2(η2-H2) (1) and its HD and D2 isotopomers are reported. The vibrational data and force constants support the well-established η2-bonding mode for the H2 ligand and provide unambiguous assignments for all metal−hydrogen stretching and bending frequencies. The force constant for the HH stretch, 1.3 mdyn/A, is less than one-fourth the value in free H2 and is similar to that for the WH stretch, indicating that weakening of the H−H bond and formation of W−H bonds are well along the reaction coordinate to oxidative addition. The equilibrium isotope effect (EIE) for the reversible binding of dihydrogen (H2) and dideuterium (D2) to 1 and 1-d2 has been calculated from measured vibrational frequencies for 1 and 1-d2. The calculated EIE is “inverse” (1-d2 binds D2 better than 1 binds H2), with KH/KD = 0.78 at 300 K. The EIE calculated from vibrational frequencies may be resolve...
Defects in a W(112) surface

Abstract We have used high resolution low-energy electron diffraction to characterize a high index surface, W(112) after repeated high temperature (∼2150° C) thermal cyclings. A variety of defects including random steps with monatomic step height, surface misorientation and mosaic structures were observed. The Bragg peak position of the diffraction beam from a particular micrograin was shown to oscillate along the two-dimensional reciprocal “rod”. Based on a previous calculation, the oscillation of the Bragg peak was interpreted as the result of the scattering of the electron from a surface with a small misorientation angle with respect to the (112) plane. A single grain with no misorientation and with several hundred A ordered region was found to exist on the surface.
Hydroxy bridging in cobalt (II) pyrophosphate complexes

Abstract Spectrophotometric and conductometric titrations indicate that when solutions containing cobalt (II) and P2O7−4 ions in a molar ratio of 1:2 are titrated with OH− ions a bridged dimeric complex ion with the composition [CO2(P2O7)4(OH)3]−15 seems to form.
Growth hormone and insulin-like growth factor-I measurements in high growth ( hg ) mice

Effects of a recessive gene causing high growth (hg) were studied on two major components of the growth axis in mice. Plasma and pituitary levels of growth hormone and plasma levels of insulin-like growth factor I (IGF-I) were measured in three lines homozygous for hg, each compared with a control line of alike genetic background but wild type for the hg locus (Hg). Line Gh (hghg) and line GH (HgHg) are from a line which had undergone long-term selection for high postweaning weight gain; line Ch (hghg) and line CH (HgHg) were extracted from the second backcross of Gh to C57BL/6J; line L54 (hghg) was from the sixth backcross to C57BL/6J (B6) (HgHg). Pituitary GH levels and plasma IGF-I levels were measured in both sexes at 3, 4.5, 6 and 9 wk of age. Plasma growth hormone was measured in 8- to 12-wk-old males at hourly intervals from 08.00 to 17.00. Body weight in lines homozygous for hg at 6 and 9 wk of age was 10-30% greater than in control lines. The ontogeny of this increased growth depended on genetic background. Pituitary growth hormone content was 52% lower in the two hghg lines measured (lines Ch and Gh) than in control lines at 4.5, 6 and 9 wk. Plasma growth hormone levels were also much lower in hg mice, with values only 20-30% of those in their respective controls. hg lines showed consistently low plasma growth hormone levels throughout the 9 hr sampling period, while control lines expressed the characteristic pulsatile hormone secretion.(ABSTRACT TRUNCATED AT 250 WORDS)
Strategies for Managing Barriers to the Writing Process

Publication is essential to advancing nursing knowledge for clinical practice, but relatively few nurses publish the results of their research or other writings about clinical practice issues. This article identifies some common barriers to writing for publication-personal factors, such as inadequate knowledge and writing skills, lack of confidence, and low motivation for writing for publication; and situational factors, such as limited time, energy, and other resources constraints-and discusses strategies for managing such barriers. Key words:
TRACE METAL SPECIATION IN NATURAL WATERS: COMPUTATIONAL VS. ANALYTICAL

Improvements in the field sampling, preservation, and determination of trace metals in natural waters have made many analyses more reliable and less affected by contamination. The speciation of trace metals, however, remains controversial. Chemical model speciation calculations do not necessarily agree with voltammetric, ion exchange, potentiometric, or other analytical speciation techniques. When metal-organic complexes are important, model calculations are not usually helpful and on-site analytical separations are essential. Many analytical speciation techniques have serious interferences and only work well for a limited subset of water types and compositions. A combined approach to the evaluation of speciation could greatly reduce these uncertainties. The approach proposed would be to (1) compare and contrast different analytical techniques with each other and with computed speciation, (2) compare computed trace metal speciation with reliable measurements of solubility, potentiometry, and mean activity coefficients, and (3) compare different model calculations with each other for the same set of water analyses, especially where supplementary data on speciation already exist. A comparison and critique of analytical with chemical model speciation for a range of water samples would delineate the useful range and limitations of these different approaches to speciation. Both model calculations and analytical determinations have useful and different constraints on the range of possible speciation such that they can provide much better insight into speciation when used together. Major discrepancies in the thermodynamic databases of speciation models can be evaluated with the aid of analytical speciation, and when the thermodynamic models are highly consistent and reliable, the sources of error in the analytical speciation can be evaluated. Major thermodynamic discrepancies also can be evaluated by simulating solubility and activity coefficient data and testing various chemical models for their range of applicability. Until a comparative approach such as this is taken, trace metal speciation will remain highly uncertain and controversial.
Fault modeling for FinFET circuits

FinFETs are expected to supplant planar CMOS field-effect transistors (FETs) in the near future, owing to their superior electrical characteristics. From a circuit testing viewpoint, it is unclear if CMOS fault models are comprehensive enough to model all defects in FinFET circuits. In this work, we address the above problem using mixed-mode Sentaurus TCAD device simulations and demonstrate that while faults defined for planar MOSFETs show significant overlaps with FinFETs, they are insufficient to encompass all regimes of operation. Results indicate that new fault models are needed to adequately capture the behavior of logic gates based on independent-gate FinFETs with opens on the back gate, and shorted-gate FinFETs which have been accidentally etched into independent-gate structures.
Fluoride inhibition of yeast enolase: Crystal structure of the enolase–Mg2+–F−–Pi complex at 2.6 Å resolution

Enolase in the presence of its physiological cofactor Mg2+ is inhibited by fluoride and phosphate ions in a strongly cooperative manner (Nowak, T, Maurer, P. Biochemistry 20:6901, 1981). The structure of the quaternary complex yeast enolase-Mg(2+)-F(-)-Pi has been determined by X-ray diffraction and refined to an R = 16.9% for those data with F/sigma (F) > or = 3 to 2.6 A resolution with a good geometry of the model. The movable loops of Pro-35-Ala-45, Val-153-Phe-169, and Asp-255-Asn-266 are in the closed conformation found previously in the precatalytic substrate-enzyme complex. Calculations of molecular electrostatic potential show that this conformation stabilizes binding of negatively charged ligands at the Mg2+ ion more strongly than the open conformation observed in the native enolase. This closed conformation is complementary to the transition state, which also has a negatively charged ion, hydroxide, at Mg2+. The synergism of inhibition by F- and Pi most probably is due to the requirement of Pi for the closed conformation. It is possible that other Mg(2+)-dependent enzymes that have OH- ions bound to the metal ion in the transition state also will be inhibited by fluoride ions.
The soil macrofauna and organochlorine insecticide residues at twelve agricultural sites near Huntingdon

SUMMARY Ten arable fields and two apple orchards were chosen from a total of thirty-five sites visited to represent typical soils, crop rotations and insecticide applications in the Huntingdon area of East Anglia. Pitfall traps were used to collect insects and other invertebrates during fortnightly periods from early April until harvesting and in one orchard until the following February. Estimates of active biomass were obtained for several groups of invertebrates and differences between the sites are discussed. Samples of beetles, earthworms and slugs were collected during June and were sent with soil samples to the Government Chemist for analysis of organochlorine residues. The soil residues are compared with those in respective invertebrate samples and with stated application rates. It is concluded that soil invertebrates could form a regular source of pesticide residues for ground-feeding birds but that the levels are generally too low to cause acute poisoning.
Guarding the Red Guardians: Thinking about Soviet and Russian Civil-Military Relations

I wish to thank Mary Jo Desch, Ted Hopf, and Bruce Porter for their very helpful comments on earlier drafts of this essay. I also wish to acknowledge the research support of the Ford Foundation through the Olin Institute's Consensus Project.
Neutrophil Chemotaxis on Silicone and Polyurethane Surfaces

Silicone vascular catheters have a greater risk of infection and produce greater inflammation in vivo and greater complement activation in vitro than other vascular catheter polymer materials. This study investigated whether polymorphonuclear leukocyte (PMNL) chemotaxis under agarose on silicone surfaces is different than on polyurethane (PU). Glass slides were coated with silicone and PU by use of a constant-speed dipping apparatus. Chemotaxis (3 h) in response to (10 27 mL) FMLP, zymosan-activated serum, and fresh serum (100%) was greater on silicone than on PU ( ). Polyclonal antibody to C5a blocked 150% of the movement P ! .05 toward serum ( ). Serum in the PMNL well significantly decreased chemotaxis toward P ! .05 FMLP on silicone ( ) but not on PU. These findings suggest that excessive complement P ! .05 activation by silicone may interfere with chemotaxis, but further work is necessary to determine whether this is relevant to an increased risk of catheter-related infection. In a prior study, we demonstrated that silicone catheters had a greater risk of infection than catheters made of other materials (polyurethane [PU], polyvinylchloride, or Teflon) [1]. The mechanism of this effect was not explained, but a possible clue was provided by the paradoxical observation that uninfected silicone catheters invoked a greater inflammatory response than other materials. Greater inflammation around silicone catheters suggested either that the silicone caused more tissue damage, resulting in a greater inflammatory response, or that it generated a stronger chemotactic gradient than other polymer materials. Subsequent in vitro demonstration that silicone catheters produced 10-fold greater complement activation [2] suggested that the effect of silicone on chemotaxis was worth pursuing further. The purpose of this study was to determine whether neutrophil chemotaxis on silicone surfaces is different than on other polymer surfaces. Such data might provide direct evidence of differences in neutrophil function on silicone surfaces in comparison with other polymers. Leukocyte chemotaxis has been studied over the years by a variety of methods, including the Boyden membrane filter method and modifications thereof [3, 4] and a method that uses agarose on polystyrene surfaces [5‐8]. We developed a modified chemotaxis under agarose method that allows the evaluation of neutrophil chemotaxis on polymer-coated slides.
Synthesis, photoconductivity and self-assembly of wurtzite phase Cu2CdxZn1−xSnS4 nanorods

Cu2CdxZn1−xSnS4 is a likely interfacial layer in Cu2ZnSnS4/CdS based thin film solar cells. It is thus important to investigate and understand the photoresponse behaviour of Cu2CdxZn1−xSnS4 in order to further improve the cell efficiency and to develop alternative buffer layer materials containing no heavy metals. We have synthesized monodispersed wurtzite phase Cu2CdxZn1−xSnS4 nanorods over the entire composition range by a facile solution based method and observed a systematic increase of the nanorod aspect ratio with increasing cadmium concentration. On the other hand, the optical band gap of Cu2CdxZn1−xSnS4 nanorods decreases linearly from 1.56 eV (x = 0) to 1.39 eV (x = 1). Smooth, uniform and dense nanorod thin films have been coated on Mo-coated glass substrates using nanorod dispersions as nano-inks by a spray deposition method. Current (I)–Voltage (V) measurements of the annealed films show the highest photoresponse for Cu2Cd0.75Zn0.25SnS4 composition. We further demonstrate that the dipole–dipole interaction between the solvent and the nanorods can be manipulated for long-range vertical self-assembly of the nanorods for the different compositions. This simple method is promising for large area coating of the absorber layer in thin film solar cells and can be extended for use with other technologically important materials.
Paclitaxel and Platinum Chemotherapy for Malignant Mixed Mullerian Tumors of the Ovary

Abstract Objective. Malignant mixed mullerian tumor (MMMT) of the ovary is a rare tumor with a dismal prognosis. The most effective therapy is unknown. The current study was undertaken to characterize a group of patients treated as if they had aggressive epithelial ovarian tumors, with cytoreductive surgery and combination paclitaxel/platinum chemotherapy. Methods. Retrospective analysis of data obtained from tumor registry and hospital records of cases of malignant mixed mullerian tumor between January 1, 1992 and January 1, 2000 treated at the Massachusetts General Hospital, Brigham and Women's Hospital, and University of Vermont was performed. Only patients treated with combination paclitaxel and platinum therapy were included in the analysis. Data were collected regarding cytoreduction, response to chemotherapy, disease-free interval, and survival. Results. Fifty-five patients were identified with MMMT. Twenty-eight patients with a clearly ovarian primary had received treatment with combination paclitaxel and platinum. Paclitaxel and carboplatin was given as second-line therapy in 2 patients who had chemoresponsive but incurable disease; the remaining patients were treated with paclitaxel and platinum therapy as first-line therapy. These 28 patients had a median (range) age of 66 (46–84 years) and stage was I in 2 patients, II in 3, III in 18, and IV in 5. Treatment was generally well tolerated. Sixteen patients of 26 treated with paclitaxel and platinum as first-line therapy achieved a complete clinical response (55%) and 6 patients achieved partial response for a total response rate of 72%. Optimal cytoreduction was associated with increased time to recurrence ( P = 0.001) but not with survival. Overall median survival for the 28 patients is 27.1 months. Conclusion. Although treatment fails many patients, a minority of patients with MMMT in this highly selected population do unexpectedly well. An aggressive approach with surgery and combination paclitaxel–platinum chemotherapy appears to offer very effective therapy.
A hybrid systems modeling framework for fast and accurate simulation of data communication networks

In this paper we present a general hybrid systems modeling framework to describe the flow of traffic in communication networks. To characterize network behavior, these models use averaging to continuously approximate discrete variables such as congestion window and queue size. Because averaging occurs over short time intervals, one still models discrete events such as the occurrence of a drop and the consequent reaction (e.g., congestion control). The proposed hybrid systems modeling framework fills the gap between packet-level and fluid-based models: by averaging discrete variables over a very short time scale (on the order of a round-trip time), our models are able to capture the dynamics of transient phenomena fairly accurately. This provides significant flexibility in modeling various congestion control mechanisms, different queuing policies, multicast transmission, etc. We validate our hybrid modeling methodology by comparing simulations of the hybrid models against packet-level simulations. We find that the probability density functions produced by ns-2 and our hybrid model match very closely with an L1-distance of less than 1%. We also present complexity analysis of ns-2 and the hybrid model. These tests indicate that hybrid models are considerably faster.
Scratch the workshop and its implications on our world of computing

In an attempt to foster an interest in Computer Science, and help students appreciate the fundamental concepts in the field, faculty at universities, in conjunction with their teaching colleagues in K-12, have expended a great deal of effort trying to come up with appealing and educational products. In this paper we focus on one of these products, Scratch, providing a description, rationale, and a summary of our experiences using Scratch in a variety of educational settings.
INTERLANGUAGE AS CHAMELEON1

The clam is made that Labov's “Observor's Paradox” and the fire methodological axioms leading to this paradox apply to inter language Thus, we may mew interlanguage as a continuum of styles, which is defined by the amount of attention paid to speech; the most systematic second-language learner speech is produced when the learner is paying the least attention to speech. Yet, when we do research, the presence of the researcher and the tasks presented to the learner, lead our subjects to pay attention to their speech. Therefore, we cannot claim that research can ever observe the most truly systematic form of a learner's interlanguage—unattended or “unmonitored” speech. The methodological implications of the claim are explored, and recommendations for research are made.
C. elegans daf-6 Encodes a Patched-Related Protein Required for Lumen Formation

Sensory organs are often composed of neuronal sensory endings accommodated in a lumen formed by ensheathing epithelia or glia. Here we show that lumen formation in the C. elegans amphid sensory organ requires the gene daf-6. daf-6 encodes a Patched-related protein that localizes to the luminal surfaces of the amphid channel and other C. elegans tubes. While daf-6 mutants display only amphid lumen defects, animals defective for both daf-6 and the Dispatched gene che-14 exhibit defects in all tubular structures that express daf-6. Furthermore, DAF-6 protein is mislocalized, and lumen morphogenesis is abnormal, in mutants with defective sensory neuron endings. We propose that amphid lumen morphogenesis is coordinated by neuron-derived cues and a DAF-6/CHE-14 system that regulates vesicle dynamics during tubulogenesis.
Visually accurate multi-field weather visualization

Weather visualization is a difficult problem because it comprises volumetric multi-field data and traditional surface-based approaches obscure details of the complex three-dimensional structure of cloud dynamics. Therefore, visually accurate volumetric multi-field visualization of storm scale and cloud scale data is needed to effectively and efficiently communicate vital information to weather forecasters, improving storm forecasting, atmospheric dynamics models, and weather spotter training. We have developed a new approach to multi-field visualization that uses field specific, physically-based opacity, transmission, and lighting calculations per-field for the accurate visualization of storm and cloud scale weather data. Our approach extends traditional transfer function approaches to multi-field data and to volumetric illumination and scattering.
Hydrologic monitoring: The third wave

Surface and groundwater monitoring have gone through development stages that involved manual and mechanical techniques and are now being revolutionized by microelectronics. Participants at a special half-day session of the 1985 AGU Fall Meeting in San Francisco, Calif., (entitled “Hydrologic Monitoring Writh Microelectronics”), discussed recent advances in microelectronic applications that promote more and better hydrologic data acquisition at lower costs. Of particular interest were reports on the development of new sensors and monitoring techniques. F. Milanovich (Lawrence Livermore Laboratory, Livermore, Calif.) highlighted the session with a fascinating presentation on the use of fiber optics to sense several water quality factors for in situ measurement of groundwater. Some specific organic contaminants can be determined so the sensors lend themselves to monitoring groundwater pollution. S.E. Silliman (University of Arizona, Tucson) found that thermistor probes in a borehole could accurately detect where water was flowing through interconnected fractures from another borehole. This technique appears to have interesting potential particularly where dyes and chemical tracers need to be avoided.
Clinical Paradigm Clashes: Ethnocentric and Political Barriers to Native American Efforts at Self‐Healing

Euro-American theories of psychotherapeutic intervention focus on therapist behavior or the therapeutic relationship, conceived in dyadic terms. The cultural prototype is individualistic and rationalistic: a one-to-one conversation in which the patient discloses and discusses innermost feelings in regular office visits. This may be appropriate for modern Euro-Americans. However, anthropological research finds that in many traditional healing systems, intervention is communal, it utilizes dramatic ritual ordeals and altered states of consciousness rather than rational conversations, and the healer–patient relationship may be less central. This article argues that the latter approach is not ignorant of psychotherapeutic principles; it has its own (however opposed to Euro-American assumptions they may be). Understanding this paradigm clash broadens our understanding of what psychotherapeutic intervention is. It also allows clinicians and policy makers to support traditional peoples in their own efforts at self-healing. Examples will be drawn from the author's work on the healing ceremonies of the Native American Church among contemporary Navajos. [cultural psychiatry, psychotherapeutic intervention, clinical paradigm clash, healing, Native American Church]
Fabrication of polycaprolactone scaffolds using a sacrificial compression-molding process

A method of compression-molding fine-powder blends of polycaprolactone (PCL) and poly(ethylene oxide) (PEO) and subsequently dissolving the PEO phase was investigated to prepare porous PCL scaffolds. Different mixing ratios of the two polymers from 20 to 70% PCL were used to study the effect of the mixing ratio on the morphology formation of the scaffold. The mixing ratio was found to play an important role in affecting the porosity of the scaffold and the size of pores. Murine embryonic stem cell derived osteogenic cells were utilized to test the suitability of these scaffolds in tissue engineering applications. The seeded cells were able to colonize and grow in these scaffolds. Based on the overall consideration of morphology, mechanical performance, and ability for cell attachment and proliferation, the scaffolds with approximately 30-40% PCL appear to be an appropriate choice for tissue engineering. These findings suggest that sacrificial compression-molding of PCL-PEO powder blends can be used in the generation of biocompatible scaffolds with controllable porosity and pore size and may be used for in vitro tissue engineering applications.
A unique pollen wall mutation in the family Compositae: ultrastructure and genetics.

During a routine screening of pollen fertility in the n 5 2 chromosome race of Haplopappus gracilis, a spineless pollen wall mutation was discovered that renders the otherwise functional pollen grains completely unrecognizable as Compositae pollen. Normal Haplopappus pollen is characterized by an outer layer, the ektexine, consisting of large spines supported by a roof (tectum), which in turn is supported by collumellae that are joined basally. A large cavity (cavea) stretches from aperture to aperture and separates columellae bases from the final ektexine unit, the foot layer. The spines, tectum, columellae, and columellae bases are filled with perforations (internal foramina), while the foot layer is without them. Immediately underlying the foot layer is a thickened, lamellate, disrupted, internal foramina-free second exine layer, the endexine. In contrast, the mutant pollen ektexine is a jumble of components with randomly dispersed spines as the only clearly definable unit. The endexine layer is similar to the endexine in normal pollen. The mutation apparently disrupts only the organization of ektexine units, and mutant pollen appears to be without the caveae and foot layer characteristic of normal pollen. In genetic tests, the mutant allele is recessive. There is a simple Mendelian pattern of inheritance of the mutant gene, and its phenotype is under sporophytic control. →
Metaphonology and Infant Vocalizations

The classical literature on infant vocalizations as possible precursors to speech reveals seemingly irreconcilable theoretical views. Jakobson (1941), for example, contended that there was no important phonetic relationship between infant vocalizations and speech, while Lewis (1936) pointed to striking phonetic similarities in infant babbling and early speech. Both views were based, at least in part, on diary studies; yet Jakobson referred to early infant vocalizations as involving “wild” or “random” sounds, while Lewis noted patterns of vocalization indicating emergence of a capacity for speech.
Advisory Councils For Business Colleges: Composition And Utilization

A major challenge facing business colleges is keeping up with the rapid changes in the business world. Business advisory councils provide an important link between business colleges and the business world. This study was conducted to gather data on the composition and utilization of these councils. The results reveal that there is widespread use of advisory councils by business colleges. The most commonly discussed issues by advisory councils were those dealing with administrative issues and student concerns while faculty issues were the least discussed. Advisory councils were also perceived as being most effective in addressing administrative and student-related issues.