cssi/SciSciGPT-SciSciNet huggingface dataset:
Acute Recovery of Patellar Tendon From Heat-Induced Shrinkage and Its Inhibition by Cross-Linking

There are two important factors that accompany heat-induced shrinkage of collagenous tissues: mechanical property degradation and partial recovery from the shrunken length (elongation) upon returning to room temperature (defined here as acute recovery). These undesirable factors reduce the efficacy of thermal therapies. We applied chemical cross-linking adjuvant to thermal treatment on New Zealand White rabbit patellar tendon complexes to explore the feasibility of reducing the impact of these undesirable side-effects. Our results have shown that with exposure to 0.5% w/v glutaraldehyde solution during heating, the recovery response of the patellar tendon tissue was decreased, and the mechanical properties of the tissue were significantly improved.
Diffusional breakdown of a Ag diffusion barrier in a Cu-Ag-Ni diffusion triple

A diffusion triple with copper and nickel sandwiching a thin diffusion barrier layer of silver was annealed for various times at 760 °C. Silver exhibits a limited solubility (0.135 atom fraction) for copper and a slight (0.01) solubility for nickel at 760 °C. The Ag barrier was breached by successive processes of Cu interdiffusion, interface instability of the Ag-Ni interface, and growth of Cu-Ni protrusions from the Ag-Ni interface to ultimately bridge the Ag barrier. The kinetics of widening of the Ag barrier were determined and interpreted in terms of the diffusion concentration profiles and the plastic deformation of the Ag barrier by the Cu-Ni protrusions.
Paper chromatography of the most polar α-ketolic steroids

Abstract Two improved Zaffaroni-type systems for paper chromatography of the most polar α-ketolic steroids, the methylene chloride-ethylene glycol system and the fluorobenzene-ethylene glycol system, are described. A comparison of the mobilities of a number of α-ketols in these systems with the mobilities in toluene-ethylene glycol is given.
INFRARED SPECTRA OF POLYCYCLIC AROMATIC HYDROCARBONS : NITROGEN SUBSTITUTION

The B3LYP/4-31G approach is used to compute the harmonic frequencies of substituted naphthalene, anthracene, and their cations. The substitutions include cyano (CN), aminio (NH2), imino (NH), and replacement of a CH group by a nitrogen atom. All unique sites are considered, namely 1 and 2 for naphthalene and 1, 2, and 9 for an'tracene, except for the imino, where only 2-iminonaphthalene is studied. The IR spectra of these substituted species are compared with those of the unsubstituted molecules. The addition of a CN group does not significantly affect the spectra except to add the CN stretching frequency. Replacing a CH group by N has only a small effect on the IR spectra. The addition of the NH2 group dramatically affects the neutral spectra, giving it much of the character of the cation spectra. However, the neutral 2-irrinonaphthalene spectra looks more like that of naphthalene than like the 2-aminonaphthalene spectra.
Photoelectronic Radiology Department

The University of Arizona Department of Radiology first considered establishing a photoelectronic radiology department in 1973. It seemed clear that the technology had progressed far enough for us to investigate the possibility of total film replacement.' Data from the space program in particular indicated at that time that sophisticated television images over 1000 x 1000 lines were approaching the detail seen on the traditional x-ray film. This technology has been known over many years of research and development as "photoelectronic imaging devices (PEID) ."14 However, at that time film replacement was out of the question. What was not out of the question was the consideration of using a subtraction technique, "digital video subtraction angiography." To this end, we, and independently the University of Wisconsin,314 proceeded to develop this technology.5'6 Our intravenous video subtraction images in patients started in our research laboratory in 1977 and in March of 1980 we opened a biplane special procedures room dedicated only to photoelectronic imaging (no film).7'8 Digital video subtraction angiography has been successful and is described in much greater detail in these Proceedings by other authors. Current efforts are under way toward total replacement of film. This is an immense problem, one that will require a much greater sophistication of computers, storage devices, system analysis, and cooperation from both the radiologist and the clinician.9'10 In a theoretical study we converted our 65,000 procedures-per-year department to complete photoelectronic imaging (no film) and estimated that we would save approximately five million dollars over ten years.15 Extrapolating this to the entire United States would result in a conservative estimate of saving one billion dollars per year. Not included in these mathematics are cost-effective savings of the physicians' time and effort.© (1981) COPYRIGHT SPIE--The International Society for Optical Engineering. Downloading of the abstract is permitted for personal use only.
Are international environmental agreements enforceable? implications for institutional design

Over the past several decades, European international environmental institutions have evolved, heeding institutionalist calls for stronger institutions backed by sanctioning and dispute settlement mechanisms. This apparent increase in institutional strength has led to a corresponding increase of the behavioral effectiveness, or active compliance management of institutions as observed in the incidence of arbitral tribunal decisions. However, upon closer examination, it is apparent that this behavioral effectiveness has not been exclusively due to provisions for arbitral tribunal decisions within international environmental agreements. Rather, the incidence and enforcement of these arbitral tribunal decisions is linked to the institutional design of the enforcement mechanisms. Most international environmental agreements rely on parties to raise disputes and enforce commitments, causing individual countries to bear the cost of enforcement. In addition, bringing a dispute to an arbitral tribunal requires the accordance of the parties to the dispute. In contrast, the European Court of Justice allows for enforcement to originate from a strong central authority and for the cases of arbitration to be filed unilaterally. International environmental agreements that have been joined by the European Community and have a provision for an arbitral tribunal have stronger enforcement mechanisms, are more likely to result in enforcement action, and are more effective in generating behavioral change.
Structures of quartz (100)- and (101)-water interfaces determined by x-ray reflectivity and atomic force microscopy of natural growth surfaces

Abstract The structures of prismatic (100) and pyramidal (101) growth faces of natural quartz crystals, and their modification upon annealing at T ≤ 400°C were investigated ex situ by atomic force microscopy (AFM) and in water by high-resolution X-ray reflectivity. AFM images revealed the presence of ∼ 0.1 to 1 μm-wide flat terraces delimited by steps of one to several unit cells in height. These steps follow approximately directions given by the intersection of growth faces. Modeling of X-ray reflectivity data indicates that surface silica groups on flat terraces have only one free Si-O bond each (presumably hydroxylated), except for some having two free Si-O bonds observed on a single (100) surface. Vertical relaxation of atomic positions (
Insights into the role of jasmonic acid-mediated defenses against necrotrophic and biotrophic fungal pathogens

Jasmonic acid (JA) is a natural hormone regulator involved in development, responses against wounding and pathogen attack. Upon perception of pathogens, JA is synthesized and mediates a signaling cascade initiating various defense responses. Traditionally, necrotrophic fungi have been shown to be the primary activators of JAdependent defenses through the JA-receptor, COI1. Conversely, plants infected with biotrophic fungi have classically been associated with suppressing JA-mediated responses. However, recent evidence has shown that certain biotrophic fungal species also trigger activation of JA-mediated responses and mutants deficient in JA signaling show an increase in susceptibility to certain biotrophic fungal pathogens. These findings suggest a new role for JA in defense against fungal biotrophs. This review will focus on recent research advancing our knowledge of JA-dependant responses involved in defense against both biotrophic and necrotrophic fungi.
A climatology of stratopause temperature and height in the polar vortex and anticyclones

[1] A global climatology of stratopause temperature and height is shown using 7 years of Microwave Limb Sounder satellite data, from 2004 to 2011. Stratopause temperature and height is interpreted in the context of the polar vortices and anticyclones defined by the Goddard Earth Observing System meteorological analyses. Multiyear, monthly mean geographic patterns in stratopause temperature and height are shown to depend on the location of the polar vortices and anticyclones. The anomalous winters of 2005/2006 and 2008/2009 are considered separately in this analysis. In the anomalous years, we show that the elevated stratopause in February is confined to the vortex core. This is the first study to show that the stratopause is, on average, 20 K colder and 5–10 km lower in the Aleutian anticyclone than in ambient air during the Arctic winter. During September in the Antarctic the stratopause is, on average, 10 K colder inside anticyclones south of Australia. The regional temperature and height anomalies, which are due to vertical ageostrophic motion associated with baroclinic instability, are shown to be climatological features. The mean structure of the temperature and height anomalies is consistent with moderate baroclinic growth below the stratopause and decay above. This work furthers current understanding of the geography of the stratopause by emphasizing the role of synoptic baroclinic instability, whereby anticyclones establish zonally asymmetric climatological patterns in stratopause temperature and height. This work highlights the need to consider zonal asymmetries when calculating upper stratospheric temperature trends.
Reversal of tamoxifen resistant breast cancer by low dose estrogen therapy

Currently, the standard of care for estrogen receptor (ER)-positive breast cancer is 5 years of tamoxifen (TAM) or an aromatase inhibitor (AI) such as anastrozole. New studies indicate that extending antiestrogen therapy beyond 5 years with sequential regimens will improve disease-free survival. Based on the emerging concept that longer therapies are better, we have developed sequential models of tamoxifen-resistant breast cancer in vivo to mimic the clinical scenario of long-term antiestrogen therapy. The goal of the current study was to investigate the consequences of long-term treatment with tamoxifen on the growth of breast tumors in athymic mice. The results demonstrate that there are distinct phases of resistance to tamoxifen that correlate with time of treatment and expression of HER2/neu mRNA. In the treatment phase, 17beta-estradiol (E2) stimulated growth, while TAM inhibited growth of MCF-7 tumors (MCF-7E2). The withdrawal of treatment, mimicking the use of an AI, completely prevented growth. In Phase I resistance, the tumors (MCF-7TAMST) were growth-stimulated by either E2 or TAM, but inhibited by no treatment, fulvestrant, or E2 + fulvestrant. Phase II-resistant tumors (MCF-7TAMLT) were treated for more than 5 years and growth-stimulated by TAM. However, no treatment, fulvestrant, or E2 completely inhibited growth. Interestingly, the few tumors (MCF-7TAMLT) that survived in response to E2 were robustly re-stimulated by E2 after transplantation into new generations of athymic mice. These E2-stimulated tumors (MCF-7TAME) were inhibited by TAM in a dose-dependent similar to their parental tumors (MCF-7E2). In addition, the MCF-7TAME tumors were inhibited by either no treatment or fulvestrant. HER2/neu and HER3 mRNAs were over-expressed in TAM-stimulated MCF-7TAMLT tumors and remained high in E2-stimulated MCF-7TAME tumors. The data indicate that complete reversal of resistance to TAM can be achieved with the use of low dose E2 therapy. Also, these data suggest that over-expression of HER2/neu alone is insufficient to predict resistance to TAM. Based on the results, we suggest using an alternating treatment regimen, cycling antiestrogen with estrogen therapy to avoid drug-resistance.
Abstract 1976: Targeting the PP2A tumor suppressor for the treatment of human pancreatic cancer.

Proceedings: AACR 104th Annual Meeting 2013; Apr 6-10, 2013; Washington, DC Pancreatic cancer is a disease with a high rate of mortality, as it is generally diagnosed in the advanced stages when few effective treatments are available. Given the clinical aggressivity of this disease and the lack of good treatment options, the development of new therapeutic agents for the treatment of pancreatic cancer is of the upmost importance. Recent reports have suggested that disruption of several key signal transduction pathways is important for the development of pancreatic cancer. Many of these pathways are negatively regulated by PP2A, a phosphatase that plays a role in many cellular processes, and whose inhibition is essential for cell transformation. PP2A inhibition can occur through inactivation by viral oncogenes, mutation of specific subunits, or by overexpression of endogenous inhibitors, including SET (also known as I2PP2A) and Cellular Inhibitor of PP2A (CIP2A). Here, we show that SET and CIP2A are frequently overexpressed in human pancreatic cancer cells and primary patient samples. This overexpression results in decreased PP2A activity, and overexpression and stabilization of a key PP2A target, c-Myc. Knockdown of SET or CIP2A increases PP2A activity and reduces tumorigenic potential. Furthermore, inhibition of SET using a peptide mimetic (OP449) in pancreatic cancer cell lines increases PP2A activity, reduces migration and invasion, and decreases tumorigenic potential. Thus, antagonizing SET and CIP2A could be an innovative approach for the treatment of human pancreatic cancer. Citation Format: Amy Farrell, Colin Daniel, Zhiping Wang, Brittany Allen-Petersen, Dale Christensen, Brett Sheppard, Charles D. Lopez, Rosalie Sears. Targeting the PP2A tumor suppressor for the treatment of human pancreatic cancer. [abstract]. In: Proceedings of the 104th Annual Meeting of the American Association for Cancer Research; 2013 Apr 6-10; Washington, DC. Philadelphia (PA): AACR; Cancer Res 2013;73(8 Suppl):Abstract nr 1976. doi:10.1158/1538-7445.AM2013-1976
19F NMR relaxation studies on 5-fluorotryptophan- and tetradeutero-5-fluorotryptophan-labeled E. coli glucose/galactose receptor.

19F NMR relaxation studies have been carried out on a fluorotryptophan-labeled E. coli periplasmic glucose/galactose receptor (GGR). The protein was derived from E. coli grown on a medium containing a 50:50 mixture of 5-fluorotryptophan and [2,4,6,7-2H4]-5-fluorotryptophan. As a result of the large λ-isotope shift, the two labels give rise to separate resonances, allowing relaxation contributions of the substituted indole protons to be selectively monitored. Spin-lattice relaxation rates were determined at field strengths of 11.75 T and 8.5 T, and the results were analyzed using a model-free formalism. In order to evaluate the contributions of chemical shift anisotropy to the observed relaxation parameters, solid-state NMR studies were performed on [2,4,6,7-2H4]-5-fluorotryptophan. Analysis of the observed 19F powder pattern lineshape resulted in anisotropy and asymmetry parameters of Δσ=−93.5 ppm and π=0.24. Theoretical analyses of the relaxation parameters are consistent with internal motion of the fluorotryptophan residues characterized by order parameters S2 of ∼1, and by correlation times for internal motion ∼10-11 s. Simultaneous least squares fitting of the spin-lattice relaxation and line-width data with τi set at 10 ps yielded a molecular correlation time of 20 ns for the glucose-complexed GGR, and a mean order parameter S2=0.89 for fluorotryptophan residues 183, 127, 133, and 195. By contrast, the calculated order parameter for FTrp284, located on the surface of the protein, was 0.77. Significant differences among the spin-lattice relaxation rates of the five fluorotryptophan residues of glucose-complexed GGR were also observed, with the order of relaxation rates given by: R inf1F sup183 >R inf1F sup127 ∼R inf1F sup133 ∼R inf1F sup195 >R inf1F sup284 . Although such differences may reflect motional variations among these residues, the effects are largely predicted by differences in the distribution of nearby hydrogen nuclei, derived from crystal structure data. In the absence of glucose, spin-lattice relaxation rates for fluorotryptophan residues 183, 127, 133, and 195 were found to decrease by a mean of 13%, while the value for residue 284 exhibits an increase of similar magnitude relative to the liganded molecule. These changes are interpreted in terms of a slower overall correlation time for molecular motion, as well as a change in the internal mobility of FTrp284, located in the hinge region of the receptor.
Beyond the forest primaeval

From Coastal Wilderness to Fruited Plain: A History of Environmental Change in Temperate North America from 1500 to the Present. By Gordon G. Whitney Cambridge University Press: 1994. Pp. 451. £45, $54.95.
Incidence of monoecy and dichogamy in relation to self-fertilization in angiosperms

The evolution of many floral traits, including monoecy and dichogamy, has been attributed to selection for avoidance of self-fertilization. If this explanation is correct, monoecy and dichogamy should be uncommon among self-incompatible species because physiological barriers prevent self-fertilization in such species. In fact, self-fertility was independent of sexual system in a sample of 588 hermaphroditic and monoecious angiosperms. Overall, dichogamy was also equally common among self-incompatible and self-compatible species. When the different forms of dichogamy were analyzed separately, only intrafloral protogyny was associated with self-compatibility. This form of dichogamy is less common among angiosperms than intrafloral protandry, which is probably less effective at reducing self-fertilization. Thus, avoidance of self-fertilization has probably been less important in the evolution of monoecy and most forms of dichogamy than other factors, such as avoidance of pollen-pistil interference, and flexibility of resource allocation to male and female functions.
Lower gastrointestinal bleeding

BACKGROUND: Lower gastrointestinal bleeding can be a confusing clinical conundrum, the satisfactory evaluation and management of which requires a disciplined and orderly approach. Diagnosis and management has evolved with the development of new technology such as selective mesenteric angiography and colonoscopy. PURPOSE: This study was undertaken to review the available data in the literature and to determine the current optimum method of evaluation and management of lower gastrointestinal hemorrhage most likely to result in a successful outcome. METHODS: Data available on the topic of lower gastrointestinal bleeding in the English literature were obtainedviaMEDLINE search and were reviewed and analyzed. RESULTS: The colonic origin of lower gastrointestinal hemorrhage in order of decreasing incidence is diverticulosis, inflammatory bowel disease, including ischemic and infectious colitis, colonic neoplasia, benign anorectal disease, and arteriovenous malformations. Approximately 10 to 15 percent of all cases of rectal bleeding are attributable to a cause that is proximal to the ligament of Treitz. Small intestinal sources such as arteriovenous malformations, diverticula, and neoplasia account for between 3 and 5 percent of all cases. Colonoscopy successfully identified an origin in severe hematochezia in 74 to 82 percent of cases. Mesenteric angiography has a sensitivity of 42 to 86 percent. The best method of management depends on whether hemorrhage persists, the severity of continued hemorrhage, the cumulative transfusion requirement, and the specific origin of bleeding. CONCLUSION: Lower gastrointestinal hemorrhage is a complex clinical problem that requires disciplined and sophisticated evaluation for successful management. Diverticulosis is the most common cause. Colonoscopy is the diagnostic procedure of choice both for its accuracy in localization and its therapeutic capability. Selective mesenteric angiography should be reserved for those patients in whom colonoscopy is not practical. Precise identification of the bleeding source is crucial for a successful outcome. Specific directed therapy, such as segmental colonic resection for bleeding diverticulosis, is associated with the highest success rate and the lowest morbidity. A complete review of lower gastrointestinal bleeding is contained herein.
Anxiety and the Archive: Understanding Plagiarism Detection Services as Digital Archives

Abstract Based on a case study of the popular plagiarism detection service Turnitin, particularly its “Legal Document,” this article contends that plagiarism detection services should be viewed as digital archives. Services like Turnitin not only seek to regulate what constitute original texts and appropriate writing practices but also to advance conceptions of the work that archives should do in storing and circulating texts in digital spaces. This article concludes that the services we sometimes use to ensure the integrity of students’ texts can themselves be of questionable integrity—largely through the design of their archives. As increasing numbers of texts take digital form, the problems and promise of digital archives will demand thoughtful responses that do not rush to replace questionable writing and research practices with equally troubling pedagogical and archival ones. These thoughtful responses start with exploring the use of plagiarism detection service archival technology in unadvertised ways.
The plight of China to construct e-government and its path selection

E-government is a requirement and key part for governments to develop information, and a realistic choice to improve government efficiency. The government, promoting its management capabilities and service levels through the e-government, can provide the enterprises and public with extensive and convenient information and service; In turn, by means of e-government, the public can be more widespread participation in government decision-making and management and supervision of government action to promote the government in the lawful administration. The paper, analyzing from the connotation of e-government, discuses the reality of our plight to construct e-government, and further puts forward countermeasures and proposals to construct our e-government from three aspects: transform our concept, raise awareness and develop practical development planning.
84 UDP-Glucuronyl Transferase

We have reevaluated the capacity of newborn rat livers to conjugate bilirubin and p-nitrophenol with glucuronic acid after activation of liver homogenates with EDTA and utilizing improved assaying conditions as previously reported.
Kinetics of competitive adsorption/desorption of arsenate and phosphate at the ferrihydrite–water interface

Abstract Metal hydroxides (e.g. ferrihydrite) present in geomedia play significant roles in regulating the environmental mobilities of arsenate (As(V)) and inorganic phosphate (Pi) because of their high adsorption affinities for these oxyanions. In this study, results are presented of experiments aimed at determining individual and competitive adsorption/desorption kinetics of As(V) and Pi on ferrihydrite at pH 4 and 8. Selected samples were also subjected to As K-edge EXAFS study for understanding the changes with time in As(V) complexation on ferrihydrite in the presence/absence of Pi. Both oxyanions showed similar behavior in single ion adsorption experiments. However, when both oxyanions were loaded together, more As(V) was adsorbed than Pi. Furthermore, more pre-equilibrated Pi was desorbed by sequentially added As(V) than vice versa. Interactions of As(V) and Pi with ferrihydrite slowed down after the initial rapid adsorption/desorption. The experimentally determined adsorption/desorption kinetic data for As(V) and Pi showed good compliance with pseudo-second order, Elovich, and power-function equations. Both oxyanions competed for adsorption on ferrihydrite, and each of them showed a limited capacity to desorb the other. EXAFS analysis of selected samples indicated the presence of mononuclear (2E) and binuclear (2C) bidentate As(V) surface complexes. The Fe coordination numbers (CN) increased with increasing time and decreased with addition of Pi into the system. A higher proportion of Fe CN associated with 2E As(V) surface complexes decreased after the addition of Pi, compared to Fe CN associated with 2C As(V) surface complexes. The competitive desorption study indicates that the excessive input of Pi due to the overuse of fertilizers could mobilize As(V) from contaminated geomedia. Furthermore, insights into Pi-induced desorption of As(V) could also provide an opportunity for developing chemical treatment methods to intercept the mobilized As(V) by co-precipitation in apatite-like phases.
Do prescription stimulants increase the risk of adverse cardiovascular events?: A systematic review.

There is increasing concern that prescription stimulants may be associated with adverse cardiovascular events such as stroke, myocardial infarction, and sudden death. Public health concerns are amplified by increasing use of prescription stimulants among adults. The objective of this study was to conduct a systematic review of the evidence of an association between prescription stimulant use and adverse cardiovascular outcomes. PUBMED, MEDLINE, EMBASE and Google Scholar searches were conducted using key words related to these topics (MESH): ADHD; Adults; Amphetamine; Amphetamines; Arrhythmias, Cardiac; Cardiovascular Diseases; Cardiovascular System; Central Nervous Stimulants; Cerebrovascular; Cohort Studies; Case–control Studies; Death; Death, Sudden, Cardiac; Dextroamphetamine; Drug Toxicity; Methamphetamine; Methylphenidate; Myocardial Infarction; Stimulant; Stroke; Safety. Eligible studies were population-based studies of children, adolescents, or adults using prescription stimulant use as the independent variable and a hard cardiovascular outcome as the dependent variable. Ten population-based observational studies which evaluated prescription stimulant use with cardiovascular outcomes were reviewed. Six out of seven studies in children and adolescents did not show an association between stimulant use and adverse cardiovascular outcomes. In contrast, two out of three studies in adults found an association. Findings of an association between prescription stimulant use and adverse cardiovascular outcomes are mixed. Studies of children and adolescents suggest that statistical power is limited in available study populations, and the absolute risk of an event is low. More suggestive of a safety signal, studies of adults found an increased risk for transient ischemic attack and sudden death/ventricular arrhythmia. Interpretation was limited due to differences in population, cardiovascular outcome selection/ascertainment, and methodology. Accounting for confounding and selection biases in these studies is of particular concern. Future studies should address this and other methodological issues.
Increased phosphoribosylpyrophosphate synthetase activity in fibroblasts of hypoxanthine-guanine phosphoribosyl transferase deficient patients.

Abstract An increased activity of phosphoribosylpyrophosphate synthetase at physiological levels of inorganic phosphate is demonstrated in extracts of skin fibroblast cultures derived from a patient with Lesch-Nyhan syndrome. This eccessive response of the phosphoribosylpyrophosphate synthetase at physiological levels of inorganic phosphate results in increased levels of phosphoribosylpyrophosphate and thus contributes to purine overproduction characteristic of this disorder. The level of enzyme response in skin fibroblast extracts from the carrier mother was between activity of the patient and normals, further suggesting the x-linkage of human phosphoribosylpyrophosphate synthetase.
Phase transformation of single crystal β-tungsten nanorods at elevated temperatures

Abstract We report the phase transformation of single crystal β-phase W(100) nanorods that occurs at an elevated temperature of ∼950 °C. The β-W nanorods oriented perpendicular to the flat silicon substrate were grown by an oblique angle sputter deposition technique with substrate rotation. The nanorods typically have an average length of ∼450 nm and an average width of ∼75 nm. The phase transformation was investigated by X-ray diffraction measurements of the nanorods vacuum-annealed at various temperatures in the range 700–1000 °C for 30 min at each annealing temperature. As deposited individual nanorods are found to be single crystal, as evidenced from the analysis of transmission electron microscopy diffraction patterns. Our single crystal β-phase W(100) nanorods phase transformation temperature is higher than that of the polycrystalline simple-cubic β-phase (A15) W films. Depending on the deposition conditions, W films generally transform to thermodynamically stable bcc α-phase at temperatures ranging from room-temperature to ∼650 °C. The transformation is accompanied with the removal of oxygen atoms from the β-matrix. However, our results of W rods suggest that the removal of oxygen atoms from the single crystal W nanorods is more difficult due to the absence of grain boundaries that leads to the requirement of higher annealing temperatures for the phase transformation.
Minority to Mainstream: The Amalgamation of Hispanic Customs and Traditions into American Popular Culture:

In the United States, the portion of the population that is of Hispanic descent has now become the largest minority group in the nation. Continued immigration guarantees that their numbers will grow in the coming decades. The influence of Spanish-speakers in America is increasing in all aspects of lifedomestic political issues, education, immigration policy, international relations. The social fabric of the United States is also changing to reflect the incorporation of many Hispanic cultural elements into the mainstream of American life. This article examines the process of cultural amalgamation and considers some examples in the present-day America.
Successful kidney transplantation with current-sera-negative/historical-serapositive T cell crossmatch

Etude de 5 observations: 1 rejet accelere, 1 rejet au bout de 3 mois, 3 bons resultats, reins transplantes fonctionnant depuis 10, 14 et 17 mois
Facile synthesis of Ag nanocubes and Au nanocages

This protocol describes a method for the synthesis of Ag nanocubes and their subsequent conversion into Au nanocages via the galvanic replacement reaction. The Ag nanocubes are prepared by a rapid (reaction time < 15 min), sulfide-mediated polyol method in which Ag(I) is reduced to Ag(0) by ethylene glycol in the presence of poly(vinyl pyrrolidone) (PVP) and a trace amount of Na2S. When the concentration of Ag atoms reaches supersaturation, they agglomerate to form seeds that then grow into Ag nanostructures. The presence of both PVP and Na2S facilitate the formation of nanocubes. With this method, Ag nanocubes can be prepared and isolated for use within approximately 3 h. The Ag nanocubes can then serve as sacrificial templates for the preparation of Au nanocages, with a method for their preparation also described herein. The procedure for Au nanocage preparation and isolation requires approximately 5 h.
Formation of an all ferrous Fe4S4 cluster in the iron protein component of Azotobacter vinelandii nitrogenase

Abstract The iron protein component of nitrogenase from Azotobacter vinelandii is an iron sulfur protein containing an Fe 4 S 4 cluster which transfers electrons at low potential in combination with MgATP hydrolysis to the MoFe protein during nitrogenase catalysis. The Fe 4 S 4 1+ = Fe 4 S 4 2+ + e redox couple has been suggested as the redox reaction involved in a one-electron transfer process occurring repeatedly during enzymatic catalysis. We report kinetic, microcoulometric, EPR, and reactivity measurements which suggest that an all ferrous Fe 4 S 4 0 cluster state can be produced in the Fe protein at biochemical relevant potentials and therefore may be a viable redox state involved in nitrogenase catalysis. Chemical decomposition by bipyridine in the absence of added reductant of this proposed Fe 4 S 4 0 cluster results in the formation of 3.7 Fe(bipyd) 3 2+ , confirming that the iron atoms are all Fe 2+ in the protein bound cluster. This FeS 4 0 cluster of the Fe protein in the presence of MgATP and MoFe protein produces hydrogen and reduces acetylene to ethylene in the absence of added reductant. The FeS 4 0 state has not been previously observed in a biological system nor isolated as a crystalline solid from Fe 4 S 4 model compound studies, although its formation has been suspected and sought. The ease with which the Fe 4 S 4 0 state can be prepared suggests that it may occur in other Fe 4 S 4 proteins and may be relevant in other biochemical processes. A possible reaction sequence for the formation of this redox state requiring ATP utilization during nitrogenase catalysis is explored.
The inhibition of pro-apoptotic ICE-like proteases enhances HIV replication

Accelerated programmed cell death, or apoptosis, contributes to the CD4+ T-cell depletion characteristic of infection by human immunodeficiency virus (HIV). It has therefore been proposed that limiting apoptosis may represent a therapeutic modality for HIV infection. We found, however, that T leukemia cells or peripheral blood mononuclear cells (PBMCs) exposed to HIV-1 underwent enhanced viral replication in the presence of the cell death inhibitor, N-benzyloxycarbonyl-Val-Ala-Asp-fluoromethylketone (z-AVD-fmk). Furthermore, z-VAD-fmk, which targets the pro-apoptotic interleukin-1 beta-converting enzyme (ICE)-like proteases, stimulated endogenous virus production in activated PBMCs derived from HIV-1-infected asymptomatic individuals. These findings suggest that programmed cell death may serve as a beneficial host mechanism to limit HIV spread and that strategies to inhibit it may have deleterious consequences for the infected host.
The Offspring‐Size/Clutch‐Size Trade‐Off in Mammals

The Smith-Fretwell model for optimal offspring size assumes the existence of an inverse proportional relationship (i.e., trade-off) between the number of offspring and the amount of resources invested in an individual offspring; virtually all of the many models derived from theirs make the same trade-off assumption. Over the last 30 years it has become apparent that the predicted proportionality is often not observed when evaluated across species. We develop a general allometric approach to correct for size-related differences in the resources available for reproduction. Using data on mammals, we demonstrate that the predicted inverse proportional relationship between number of offspring and offspring size is closely approached after correcting for allocation, though there is a slight curvature in the relationship. We discuss applications for this approach to other organisms, possible causes for the curvature, and the usefulness of allometries for estimating life-history variables that are difficult to measure.
Guanfacine enhances inhibitory control and attentional shifting in early abstinent cocaine-dependent individuals

Objectives:Attenuation of adrenergic drive and cognitive enhancement, via stimulation of alpha2 pre- and post-synaptic receptors, may selectively enhance executive performance in early abstinent cocaine-dependent individuals. As these cognitive processes underpin important treatment-related behaviors, the alpha2 agonist, guanfacine HCl, may represent an effective pharmaco-therapeutic intervention.Methods:Twenty-five early abstinent cocaine-dependent individuals were administered a battery of neurocognitive tasks on entry into treatment (baseline) and again following 3 weeks of either placebo or guanfacine treatment (up to 3 mg). Tasks included: Stop Signal, Stroop, 3-Dimentional Intra-dimensional/Extra-dimensional (IDED) task, Spatial Working Memory (SWM), Paired Associates Learning (PAL), Verbal Fluency and the Rey Auditory Verbal Learning Test (RAVLT).Results:Compared with placebo, the guanfacine group demonstrated attenuated anxiety and negative affect as well as improved performance on selective execu...
Microsomal Prostaglandin E Synthase-1 Deficiency Is Associated with Elevated Peroxisome Proliferator-activated Receptor γ: REGULATION BY PROSTAGLANDIN E2 VIA THE PHOSPHATIDYLINOSITOL 3-KINASE AND AKT PATHWAY

mPGES-1 (microsomal PGE synthase-1) is an inducible enzyme that acts downstream of cyclooxygenase (COX) and specifically catalyzes the conversion of prostaglandin (PG) H2 to PGE2 under basal as well as inflammatory conditions. In this study, using mouse embryo fibroblasts (MEFs) isolated from mice genetically deficient for the mPges-1 gene, we show basal elevation of peroxisome proliferator-activated receptor γ (PPARγ) expression (protein and mRNA) and transcriptional activity associated with reduced basal PGE2. We further show that basal mPGES-1-derived PGE2 suppresses the expression of PPARγ through a cAMP-independent pathway involving phosphatidylinositol 3-kinase and Akt signaling. Using specific PPARγ agonist (rosiglitazone), PPARγ ligand (15-deoxy-Δ12,14-PGJ2), and PPARγ inhibitor (GW9662), we confirm that activation of PPARγ blocks interleukin-1β-induced up-regulation of COX-2, mPGES-1, and their derived PGE2. Furthermore, we demonstrate that up-regulation of PPARγ upon genetic deletion of mPGES-1 is responsible for reduced COX-2 expression under basal as well as interleukin-1β-stimulated conditions. This study provides evidence for the first time that mPGES-1 deletion not only decreases proinflammatory PGE2 but also up-regulates anti-inflammatory PPARγ, which has the ability to suppress COX-2 and mPGES-1 expression and PGE2 production. Thus, mPGES-1 inhibition may limit inflammation by multiple mechanisms and is a potential therapeutic target.
Bioeconomic analysis of a minimum size limit for Gulf of Alaska sablefish using a yield per recruit model

Abstract To evaluate the potential of increasing yield in the Gulf of alaska sablefish (Anoplopoma fimbria) fishery with a minimum size limit, a modified yield per recruit analysis was used to explore trends in yield, equilibrium biomass, reproductive potential, and economic value. The Gulf of Alaska sablefish catch quotas are apportioned to the fixed- and trawl-gear fisheries in the approximate amounts of 86.1% and 13.9%, respectively. The traditional yield per recruit model was modified to incorporate age-specific selectivity rates for each gear type and to compute yield from the combination of the two fisheries. The model also incorporated a discard mortality on undersized fish. With no discard mortality, yield per recruit increases with increasing size limits. However, the increases are significant only at high fishing mortality rates (greater than 0.20). With discard mortality, yields decrease with increasing size limits. Equilibrium biomass and the egg production index increase with increasing size limits, both with and without discard mortality, but the increases are negligible with discard mortality. The effects of a minimum size limit on gross and net value are similar to those on yield, with and without discard mortality, except that the fishing mortality rates that maximize net value are substantially less than those that maximize yield and gross value. As the fishing mortality rate for Gulf of Alaska sablefish is low (0.13), it was concluded that minimum size limits would be ineffective and could even be a detriment because of discard mortality.
Social structure and cultures of corruption

Abstract Corruption often creates a “briber’s dilemma”: each of the “clients” competing for a rent allocated by a government official has an incentive to pay bribes to try to obtain preferential treatment, but they would all be better off if they could mutually commit not to pay bribes. This paper uses a model of linked games to show how informal relationships among the clients may enable them to enforce agreements (or norms) against paying bribes and how historical events can lead to the development of a “culture” of corruption that can subsequently prove hard to dislodge.
The Determination of Impedance with a Double-Slug Transformer

Formulas are derived and techniques given by means of which impedance measurements can be made by the use of a double-slug transformer. The required parameters are the length, spacing, position, and "effective" dielectric constant of the slugs, and the wavelength. A means for the experimental determination of the "effective" dielectric constant is described. The only quantitative measurements required are of length. A qualitative recognition of the electrically matched condition is needed.
The architecture and performance of CAVASS

Our group has been developing medical image software systems since the early 1980s. Our latest system, CAVASS, is freely available, open source, integrated with popular toolkits, and runs on Windows, Unix, Linux, and Mac OS. The architecture of CAVASS incorporates parallel processing by exploiting inexpensive networks of workstations. CAVASS is directed at the visualization, processing, and analysis of nD medical imagery, so support for large medical imagery data and the efficient implementation of algorithms is given paramount importance. We describe the architecture of CAVASS, the parallelization strategy, and present the results of comparing the implementation of CAVASS algorithms with similar algorithms in ITK and VTK for a host of operations.
Analysis and optimization of third order intermodulation distortion mechanisms in AlGaAs/GaAs heterojunction bipolar transistors

The third-order intermodulation distortion (IMD3) mechanisms of HBTs (heterojunction bipolar transistors) are analyzed using Volterra series theory. The third-order nonlinear currents generated by the device nonlinearities are evaluated for this purpose. Second-harmonic loading is addressed in view of IMD3 optimization while, at the same time, maintaining high gain through conjugate matching at the fundamental frequency. It is shown that IMD3 depends on a complex process involving interactions between various nonlinear elements and is highly sensitive to C/sub bc/ generated nonlinear current. The interaction of the latter with the other HBT elements significantly affects the IMD3. Optimum IMD3 occurs at high second-harmonic reflection coefficients corresponding to open load conditions. An IMD3 improvement of up to 27 dBm can be obtained by proper loading. >
The evolution of postpollination reproductive isolation in Costus

Reproductive isolation is critical to the diversification of species. Postpollination barriers may be important in limiting gene flow between closely related species, but they are relatively cryptic and their evolution is poorly understood. Here, we review the role of postpollination reproductive isolation in plants, including the various stages at which it operates and the hypotheses for how it may evolve. We then review empirical studies in the plant genus Costus, evaluating documented postpollination barriers in light of these hypotheses. We summarize isolation due to parental style length differences and present evidence supporting the hypothesis that the differences are in part a by-product of selection on floral morphology. Additionally, we show that reduced pollen adhesion, germination, and tube growth contribute to reproductive isolation between two closely related sympatric species of Costus. Geographic variation in the strength of these crossing barriers supports the hypothesis that they evolved under reinforcement, or direct natural selection to strengthen isolation.
Combatting ionic aggregation using dielectric forces—combining modeling/simulation and experimental results to explain end-capping of primary amine functionalized polystyrene

Chain-end functionalization of living poly(styryl)lithium using 1-(3-bromopropyl)-2,2,5,5-tetramethyl-1-aza-2,5-disilacyclo-pentane (BTDP) to generate primary amine end-functionalized polystyrene was investigated using high vacuum anionic polymerization techniques. 13C NMR spectroscopy and Matrix Assisted Laser Desorption Ionization Time-of-Flight Mass Spectrometry (MALDI-TOF MS) were used to evaluate polymer end-groups and demonstrated that quantitative amine functionalized polymer was attained under appropriate reaction conditions. In general, the polymerization of styrene was conducted in benzene and the end-capping reaction was performed by adding tetrahydrofuran (THF) to the reaction prior to the addition of BTDP in THF at room temperature. Results indicated that approximately 20% THF by volume is required to obtain 100% end-capping free from side reactions. When too little or no THF was present, side reactions such as lithium halogen exchange followed by Wurtz coupling resulted in unfunctionalized head-to-head dimer as well as other byproducts. Modeling and simulation of the solvent effects using hybrid methods (the so-called QM/MM method) suggest that THF effectively dissociated the anionic chain-end aggregation, thereby resulting in the desired primary amine functionalized polymer. Molecular dynamics (MD) simulations were conducted to develop an understanding of the physics of counterions involved in the end-functionalization process.
Bandgap Engineering through Controlled Oxidation of Polythiophenes

The use of Rozen's reagent (HOF⋅CH3 CN) to convert polythiophenes to polymers containing thiophene-1,1-dioxide (TDO) is described. The oxidation of polythiophenes can be controlled with this potent, yet orthogonal reagent under mild conditions. The oxidation of poly(3-alkylthiophenes) proceeds at room temperature in a matter of minutes, introducing up to 60 % TDO moieties in the polymer backbone. The resulting polymers have a markedly low-lying lowest unoccupied molecular orbital (LUMO), consequently exhibiting a small bandgap. This approach demonstrates that modulating the backbone electronic structure of well-defined polymers, rather than varying the monomers, is an efficient means of tuning the electronic properties of conjugated polymers.
A new method for perspective view registration

This paper presents a new hybrid space-frequency technique for perspective view registration which consists of two stages. A frequency-domain algorithm first estimates an affine approximation of the actual projective transformation relating two images. A space-domain algorithm then computes the projective transformation parameters through an iterative procedure where the affine approximation is used as the initial estimate. This scheme works efficiently allowing for the rapid convergence of the second stage to the optimal solution of the problem. The experimental results reported confirm the effectiveness of the method.
Selective Exposure: The Potential Boomerang Effect

This paper reports a test of selective exposure. Interviews with the audience of a film critical of American involvement in Vietnam revealed that the overwhelming majority shared the film's orientation and that eighty per cent knew about the film before entering the theater. Thus selective exposure occurred. Selective exposure, however, supposedly reinforces viewer attitudes; but for many respondents this did not occur, and for several viewers the film had a boomerang effect reducing their opposition to American policy. This effect may be explained by the different expectations members of the audience brought to the film. For those most disapproving, it violated their expectations of new information, insights, reason and logic.