cssi/SciSciGPT-SciSciNet huggingface dataset:
Band alignment and p -type doping of ZnSnN 2

Composed of earth-abundant elements, ${\mathrm{ZnSnN}}_{2}$ is a promising semiconductor for photovoltaic and photoelectrochemical applications. However, basic properties such as the precise value of the band gap and the band alignment to other semiconductors are still unresolved. For instance, reported values for the band gap vary from 1.4 to 2.0 eV. In addition, doping in ${\mathrm{ZnSnN}}_{2}$ remains largely unexplored. Using density functional theory with the Heyd-Scuseria-Ernzerhof hybrid functional, we investigate the electronic structure of ${\mathrm{ZnSnN}}_{2}$, its band alignment to GaN and ZnO, and the possibility of $p$-type doping. We find that the position of the valence-band maximum of ${\mathrm{ZnSnN}}_{2}$ is 0.39 eV higher than that in GaN, yet the conduction-band minimum is close to that in ZnO, which suggests that achieving $p$-type conductivity is likely as in GaN, yet it may be difficult to control unintentional $n$-type conductivity as in ZnO. Among possible $p$-type dopants, we explore Li, Na, and K substituting on the Zn site. We show that while ${\mathrm{Li}}_{\mathrm{Zn}}$ is a shallow acceptor, ${\mathrm{Na}}_{\mathrm{Zn}}$ and ${\mathrm{K}}_{\mathrm{Zn}}$ are deep acceptors, which we trace back to large local relaxations around the Na and K impurities due to the atomic size mismatches.
Anti-resonant hollow core fiber for precision timing applications

Many applications rely on the ultra-precise timing of optical signals through fiber, such as fiber interferometers, large telescope arrays, in phase arrayed antennae, optical metrology, and precision navigation and tracking. Environmental changes, specifically those caused by temperature fluctuations, lead to variations in the propagation delay of optical signals and thereby decrease the accuracy of the system’s timing. The cause of these variations in delay is the change in the glass properties of the optical fiber with temperature. Both the refractive index of the glass and the length of the fiber are dependent on the ambient temperature. Traditional optical fiber suffers from a delay sensitivity of 39 ps/km/K. We are reducing the temperature sensitivity of the fiber delay through the application of a novel design of optical fiber, Anti-Resonant Hollow Core Fiber. The major improvement in the thermal sensitivity of this fiber comes from the fact that the light is guided in an air core, with very little overlap into the glass structure. This drastically reduces the impact that the thermally sensitive glass properties have on the propagation time of the optical signal. Additionally, hollow core fiber is inherently radiation insensitive, due to the light guidance in air, making it suitable for space applications.
Quantification of triglyceride content in oleaginous materials using thermo-gravimetry

Abstract Laboratory analytical methods for quantification of triglyceride content in oleaginous biomass samples, especially microalgae, require toxic chemicals and/or organic solvents and involve multiple steps. In this paper, a simple triglyceride quantification method that uses thermo-gravimetry is described. This method is based on the observation that triglycerides undergo near-complete volatilization/degradation over a narrow temperature interval with a derivative weight loss peak at 420 °C when heated in an inert atmosphere. Degradation of the other constituents of oleaginous biomass (protein and carbohydrates) is largely complete after prolonged exposure of samples at 320 °C. Based on these observations, the triglyceride content of oleaginous biomass was estimated by using the following two-step process. In Step 1, samples were heated to 320 °C and kept isothermal at this temperature for 15 min. In Step 2, samples were heated from 320 °C to 420 °C and then kept isothermal at 420 °C for 15 min. Our results show that mass loss in step 2 correlated well with triglyceride content estimates obtained from conventional techniques for diverse microalgae and oilseed samples.
Neurophysiological changes in the visuomotor network after practicing a motor task.

We aimed to determine the effects of practice on the movement-related cortical oscillatory activity. Following practice, we found that the performance of the ankle plantarflexion target-matching ta...
Quality Assurance and Consumer Electronics Recycling

The information within this chapter examines the characteristics of consumer electronic recycling systems to show how quality assurance has evolved to meet the current needs of reverse logistics demanufacturers. A review of the literature reveals several trends regarding the amount of e-waste, recycling programs, the influence of international regulations, a focus on large-scale operations, and emerging recycling certifications. Given the dynamic context of consumer electronics recycling systems and opportunities for new competitive capabilities, information within this chapter provides exploratory field study insight from a small US recycling firm. A primary contribution of this chapter is found in filling a gap in the literature to advance our understanding how small firms are overcoming emerging challenges and taking advantage of opportunities facing them within reverse supply chains focusing on recycling of consumer electronics and information technology assets. The field study sheds new light on quality assurance through emerging standards, contemporary opportunities for emerging business models within the industry, and implications for the future of reverse logistics practices and research.
Novel mechanisms of fibroblast growth factor 1 function.

Publisher Summary The fibroblast growth factors (FGFs) are a multitalented family of polypeptides with a broad biological base. The FGFs are mitogens, chemoattractants, and differentiation factors for a wide variety of diverse vertebrate cell types in vitro and are known to be potent angiogenic and neurotrophic factors in vivo. The FGFs are also recognized as important contributors to a variety of pathophysiological situations in vivo, including rheumatoid arthritis, solid tumor growth, and atherogenesis. This chapter reviews the mechanisms used by the FGFs to regulate cell division. The FGF gene family is currently comprised of eight structurally related members, including two prototypes, acidic FGF, basic FGF, and six additional members, five of which are oncogenes. A feature that discriminates among the FGF prototypes and the FGF oncogenes is the absence of a classical signal peptide sequence within the FGF prototypes to direct their secretion using conventional secretory pathways. A common feature that the FGF family members share is the ability to bind the glycosaminoglycan heparin, a property that has led to the initiation of the alternative FGF nomenclature as the heparin-binding growth factors.
Synthesis and crystal structure of indium arsenate and phosphate dihydrates with variscite and metavariscite structure types

The hydrothermal synthesis, crystal structure analysis, and spectroscopic studies of InPO4·2H2O (1) and InAsO4·2H2O (2) are reported. Compound 1 is isomorphic with metavariscite: monoclinic P21/n (No. 14), a = 5.4551(3) A, b = 10.2293(4) A, c = 8.8861(3) A, β = 91.489(4)°, Z = 4, and compound 2 is isomorphic with variscite: orthorhombic Pbca (No. 61), a = 10.478(1) A, b = 9.0998(8) A, c = 10.345(1) A, Z = 8. Their three-dimensional frameworks are built of corner sharing InO4(H2O)2 octahedra and MO4 (M = P5+ or As5+) tetrahedra. The water molecules in both compounds have different environments and are involved in different types of hydrogen bonding. Infrared spectroscopy indicates that water molecules are true H2O species.
Early EFL Instruction and L1 Literacy

This study investigates the relationship between early English as a foreign language (EFL) learning and L1 literacy development in Mexican public schools. Researchers sought confirmatory findings about whether and in which ways early EFL exposure may affect students’ L1 literacy skills via a study evaluating the L1 Spanish literacy of 61 first graders using an adapted literacy assessment. Experimental group participants received EFL instruction during grades K-1, and those in the control group did not. A one-way independent samples comparison of means on the literacy assessment revealed that participants from the experimental group who had received EFL instruction scored significantly higher on all sections of the assessment than those participants in the control group. Results may inform programmatic decision-making about simultaneous or sequential approaches on the impact of early EFL on biliteracy development, with broader implications that examine who has access to early EFL instruction, and whether it will ultimately lead to higher L2 proficiency.
Host Usage and Evidence of Chestnut Lamprey Distribution in Selected Arkansas Streams

We documented distributional evidence of the parasitic fish Ichthyomyzon castaneus (Chestnut Lamprey) in selected Arkansas streams to provide information on host usage and selection of attachment sites. The species was at one point considered common in Arkansas streams, yet our sampling using boat electrofishing during late summer and fall collected Chestnut Lampreys in only 3 of the 12 streams for a total of just 8 individuals. We found evidence of Chestnut Lamprey parasitism in 7 of the 12 streams. Of the 2166 non-lamprey fishes collected, 11 individuals (0.5%) from 4 species bore evidence of Chestnut Lamprey parasitism. The most frequently parasitized host was the large-bodied, non-native Cyprinus carpio (Common Carp). There were no obvious patterns in the attachment/wound site location of parasitized fish. Further surveys of Arkansas streams are needed to evaluate trends in Chestnut Lamprey abundance and distribution.
Functional Brain Changes During Mindfulness-Based Cognitive Therapy Associated With Tinnitus Severity

Mindfulness-based therapies have been introduced as a treatment option to reduce the psychological severity of tinnitus, a currently incurable chronic condition. This pilot study of twelve subjects with chronic tinnitus investigates the relationship between measures of both task-based and resting state functional magnetic resonance imaging (fMRI) and measures of tinnitus severity, assessed with the Tinnitus Functional Index (TFI). MRI was measured at three time points: before, after, and at follow-up of an 8-week long mindfulness-based cognitive therapy intervention. During the task-based fMRI with affective sounds, no significant changes were observed between sessions, nor was the activation to emotionally salient compared to neutral stimuli significantly predictive of TFI. Significant results were found using resting state fMRI. There were significant decreases in functional connectivity among the default mode network, cingulo-opercular network, and amygdala across the intervention, but no differences were seen in connectivity with seeds in the dorsal attention network (DAN) or fronto-parietal network and the rest of the brain. Further, only resting state connectivity between the brain and the amygdala, DAN, and fronto-parietal network significantly predicted TFI. These results point to a mostly differentiated landscape of functional brain measures related to tinnitus severity on one hand and mindfulness-based therapy on the other. However, overlapping results of decreased amygdala connectivity with parietal areas and the negative correlation between amygdala-parietal connectivity and TFI is suggestive of a brain imaging marker of successful treatment.
Provider Perspectives on the Use of Evidence-based Risk Stratification Tools in the Evaluation of Pulmonary Embolism: A Qualitative Study

OBJECTIVES Providers often pursue imaging in patients at low risk of pulmonary embolism (PE), resulting in imaging yields <10% and false-positive imaging rates of 10% to 25%. Attempts to curb overtesting have had only modest success and no interventions have used implementation science frameworks. The objective of this study was to identify barriers and facilitators to the adoption of evidence-based diagnostic testing for PE. METHODS We conducted semistructured interviews with a purposeful sample of providers. An interview guide was developed using the implementation science frameworks, consolidated framework for implementation research, and theoretical domains framework. Interviews were recorded, transcribed, and analyzed in an iterative process. Emergent themes were identified, discussed, and organized. RESULTS We interviewed 23 providers from four hospital systems, and participants were diverse with regard to years in practice and practice setting. Barriers were predominately at the provider level and included lack of knowledge of the tools, particularly misunderstanding of the validated scoring systems in Wells, as well as risk avoidance and need for certainty. Barriers to prior implementation strategies included the perception of a clinical decision support (CDS) tool for PE as adding steps with little value; most participants reported that they overrode CDS interventions because they had already made the decision. All providers identified institution-level strategies as facilitators to use, including endorsed guidelines, audit feedback with peer comparison about imaging yield, and peer pressure. CONCLUSIONS This exploration of the use of risk stratification tools in the evaluation of PE found that barriers to use primarily exist at the provider level, whereas facilitators to the use of these tools are largely perceived at the level of the institution. Future efforts to promote the evidence-based diagnosis of PE should be informed by these determinants.
Network and Phase Symmetries Reveal That Amplitude Dynamics Stabilize Decoupled Oscillator Clusters

Author(s): Emenheiser, J; Salova, A; Snyder, J; Crutchfield, JP; D'Souza, RM | Abstract: Oscillator networks display intricate synchronization patterns. Determining their stability typically requires incorporating the symmetries of the network coupling. Going beyond analyses that appeal only to a network's automorphism group, we explore synchronization patterns that emerge from the phase-shift invariance of the dynamical equations and symmetries in the nodes. We show that these nonstructural symmetries simplify stability calculations. We analyze a ring-network of phase-amplitude oscillators that exhibits a "decoupled" state in which physically-coupled nodes appear to act independently due to emergent cancellations in the equations of dynamical evolution. We establish that this state can be linearly stable for a ring of phase-amplitude oscillators, but not for a ring of phase-only oscillators that otherwise require explicit long-range, nonpairwise, or nonphase coupling. In short, amplitude-phase interactions are key to stable synchronization at a distance.
Politics of Geography, Statehood, Residual Colonization and Territorial Integrity

This chapter examines some of the immediate, most pressing issues that Africa contended with at the dawn of independence. Because these issues had been largely inherited from the colonial state but spoke to the very existence of the new African state, it was necessary, even imperative, to resolve the contours of statehood, the issue of borders (the OAU decided to retain colonial boundaries), the outline of a continental union (especially the consensus on a loose or other format of a continental federation) that would work towards continental unification, and the place of regional economic communities and organizations. It aggregates the three most pertinent ideas and regional groupings, their positions on African Unity and the (role and location) of Ethiopia as OAU headquarters; to wit, it discusses the Brazzaville Group, the Casablanca Group and the Monrovia group, and also highlights the role of regional economic communities and whether or not they supported or inhibited continental unity. The chapter discusses the tension between absolute twin principles of sovereignty and non-intervention in the internal affairs of members, and the effortless OAU position of forming the African Liberation Committee (ALC) to support freedom movements especially in Rhodesia and South Africa, and the concept of NIBMAR—no independence before majority African rule in the region.
What can't be covered: The power of smiles behind the mask.

As I entered the emergency room bay, her scared eyes shouted silently. An elderly female in obvious distress, she was non-verbal except for head nods. No family accompanied her. As a medical student, I felt clinically powerless, but I knew I wanted to assist however possible. As an extrovert, it was natural for me to think in terms of a human connection. I navigated through the crowded room, hearing conversations of suspected infection, and positioned myself at the bedside.
Extracorporeal Membrane Oxygenation May Improve Outcomes After Resuscitative Thoracotomy: A National Trauma Data Bank Analysis.

BackgroundAlbeit low survival rates, resuscitative thoracotomy (RT) is considered standard for selected trauma patients. Because it has potential for rapid cardiopulmonary rescue, extracorporeal me...
Impact of P2X 7 Purinoceptors on Goblet Cell Function: Implications for Dry Eye.

By providing ~70% of the eye’s refractive power, the preocular tear film is essential for optimal vision. However, its integrity is often jeopardized by environmental and pathologic conditions that accelerate evaporation and cause sight-impairing dry eye. A key adaptive response to evaporation-induced tear film hyperosmolarity is the reflex-triggered release of tear-stabilizing mucin from conjunctival goblet cells. Here, we review progress in elucidating the roles of ion channels in mediating this important exocytotic response. Much is now known about the modulatory impact of ATP-sensitive potassium channels, nonspecific cation channels and voltage-gated calcium channels. Recently, we discovered that during unremitting extracellular hyperosmolarity, P2X7 receptor/channels also become activated and markedly impair goblet cell viability. However, our understanding of possible adaptive benefits of this P2X7 activation remains limited. In the present study, we utilized high-temporal resolution membrane capacitance measurements to monitor the exocytotic activity of single goblet cells located in freshly excised rat conjunctiva. We now report that activation of P2X7 purinoceptors boosts neural-evoked exocytosis and accelerates replenishment of mucin-filled granules after exocytotic depletion. Thus, P2X7 activation exerts a yin-yang effect on conjunctival goblet cells: the high-gain benefit of enhancing the supply of tear-stabilizing mucin is implemented at the high-risk of endangering goblet cell survival.
The Latinx Disparity in Surgery for Kidney Cancer: Data from South Texas Region

Background: The South Texas region, with a predominantly Latinx population, has a very high incidence of renal cell carcinoma (RCC), including those with tumor extending into the major blood vessels called venous tumor thrombus (VTT). There is currently no data on outcomes of RCC Latinx patients with VTT as most published studies are from predominantly Caucasian population. Therefore we performed this study to fill an urgent, unmet need. Methods: We reviewed patients who underwent radical nephrectomy with removal of VTT (called tumor thrombectomy) between 2015 and 2020. We collected data on demographics, clinical, pathological characteristics and outcomes of patients. Univariate and multivariate Cox regression analyses were used to evaluate the associations between ethnicity and disease progression or survival. Findings: We identified 112 patients, of which 67 (62%) were Latinx, and 41 (38%) were non-Latinx. Approximately 60% of patients had Level II-IV VTT; Latinx presented with a higher level of tumor thrombus(p=0.046). Latinx patients had a higher rate of no insurance (11% vs. 27%, p=0.04) and were more likely to lost to follow-up after surgery (22.4% vs. 13.3%, p=0.23) compared to non-Latinx. Fewer Latinx received systemic therapy (28% vs. 42%; p=0.13). Ninety-day mortality for the entire cohort was 3.8%. Interpretation: The Latinx population in the South Texas region present late, with advanced thrombus level, and do not have access to systemic therapy. Given symptomatic disease, surgical treatment, if feasible, is their only option. Our results highlight disparate treatment patterns which require further investigation and health-care policy changes. Funding: None to declare. Declaration of Interest: None to declare. Ethical Approval: This study was approved by the Institutional Research Ethics Board (IRB number: HSC2021108E)
A Herpes Virus as a Cause of Marek’s Disease in Chickens

Marek’s disease (MD), first described by Marek in 1907 (1), is a common infectious disease of the domestic chicken in which there is both an inflammatory and neoplastic response of the lymphoid system. Tumorous lesions commonly occur in the nervous system and the visceral organs and sometimes in the iris and ciliary body, the skeletal muscle, and feather follicles. Formerly, reference to this disease was included under the term lymphomatosis; however, since MD and lymphoid leukosis are known to be caused by different viruses, distinctive terms for each are now employed.
The direct and indirect effects of domestic violence on young children's intellectual functioning

This study examined the direct and indirect effects of domestic violence on preschoolers' intellectual functioning. The sample consisted of 100 women and their 3–5-year-old children (44 boys and 56 girls) recruited from the general community. Forty-three percent of mothers had experienced domestic violence within the last year, defined by at least one physically aggressive act by an intimate partner. Children who had witnessed domestic violence had significantly poorer verbal abilities than nonwitnesses after controlling for SES and child abuse, but there were no group differences on visual–spatial abilities. Domestic violence also indirectly affected both types of intellectual abilities through its impact on maternal depression and the intellectual quality of the home environment. Strengths and limitations of the study are discussed, as well as the implications for interventions for young child witnesses.
Iron Proteins with Dinuclear Active Sites

Iron proteins with dinuclear active sites include those containing stable nonheme, non-sulfur diiron sites. Though still dwarfed by the numbers of heme or iron-sulfur proteins, the list of proteins known to contain nonheme, non-sulfur diiron sites has steadily expanded over the past thirty years. These proteins share the following active site properties: (1) two iron atoms separated by 4 A or less; (2) stable high spin ferrous and ferric oxidation states; (3) terminal histidinyl imidazole, carboxylate and solvent ligands; (4) at least one ligand that bridges the two irons; and (5) magnetic superexchange coupling of the unpaired spins on the two irons mediated by the bridging ligand atom(s). With one possible exception, the bridging ligands are either known or are strongly suspected to include one or two carboxylates. Two distinct subclasses, the purple acid phosphatases and the flavo-diiron enzymes, seem to have no structural or functional relationships to each other or to any of the other diiron enzymes. The oxygen-carrying protein, hemerythrin, for many years served as the prototype for nonheme, non-sulfur diiron proteins. However, its structure and function have turned out to be distinct from those of the O2-activating enzymes, which now form the largest subclass of these diiron-containing proteins, with at least seven distinct types known; the most numerous of these are the alkane (including methane) monooxygenases and fatty acyl desaturases. Evidence for catalytically competent high-valent diiron intermediates resulting from reaction of the diferrous sites with dioxygen have been obtained for at least two of the O2-activating enzymes. Among the most intriguing and mysterious of the O2-activating enzymes are the membrane-bound ‘eight-His’ diiron desaturases and monooxygenases. Keywords: diiron; hemerythrin; O2-activating; monooxygenase; ribonucleotide reductase; desaturase; purple acid phosphatase; flavo-diiron
Equine ocular neoplasia: A review

Summary The following article discusses the clinical appearance, diagnosis and therapeutic options for ocular neoplasia in the horse based on anatomic location.
Effects of feeding poloxalene on milk flavor.

Abstract Cows in mid-lactation were pastured on bromegrass or rye or fed freshly cut alfalfa. Two sets of fistulated identical-twin dry cows were maintained on the same feed and feeding schedule. Half of the cows involved in each feeding trial were administered poloxalene twice daily at 0.044 g per kg of body weight. Milk samples were collected during evening milkings. Pooled milk from cows fed silage, hay, and grain in the University dairy herd served as a control to milk from cows fed bromegrass and rye pasture. Milk from two cows maintained on hay and grain served as a control to milk from alfalfa-fed cows. Flavor scores of milk samples from poloxalene-treated, untreated, and control cows were compared. Poloxalene had no important effect on milk flavor. Poloxalene reduced surface tension and pH of rumen fluid of fistulated cows. A single dose of poloxalene effectively maintained reduced rumen surface tension 24 to 36 hr.
Green with Complexity

Predators, by affecting prey behavior, can change both plant diversity and productivity in an ecosystem.
Drug Abuse Proficiency Testing

Concerning drugs in general, proficiency testing has undoubtedly been a major contributing factor to improved detection. Some of the improvement may be due to advances in technology, and this is possibly the case with improvement in the detection of morphine and methadone. The improvement in the determination of methamphetamine within three surveys over six months can clearly be attributed to proficiency testing. In drug screening for cocaine abuse, the poor results in proficiency testing for the detection of the primary metabolite, benzoylecgonine, has clearly demonstrated that laboratories are not proficient in this screening.
Sexuate difference, ontological difference: Between Irigaray and Heidegger

Animating Luce Irigaray’s oeuvre are two indissociable projects: the disruption of Western metaphysics and the thinking of sexual difference. The intersection of these two projects implies that any attempt to think through the meaning and significance of Irigaray’s notoriously fraught invocation of sexual difference must take seriously the way in which this invocation is itself always already inflected by her disruptive gesture. In this paper, I will attempt to elucidate one moment of this intersection by focusing on her critical engagement with Heidegger. In L’oubli de l’air, Irigaray criticizes Heidegger’s interpretation of the principle of identity as instantiating the same neglect of sexual difference that has been inscribed throughout the history of Western metaphysics. Moreover, Irigaray identifies the vestigial traces of this metaphysical legacy in Heidegger’s commitments to phenomenology. My claim, however, is that if we turn to Derrida’s second Geschlecht essay in order to mediate between Irigaray and Heidegger, the coimplicative nature of their projects comes into focus: on one hand, Derrida identifies within Heidegger’s work an incipient articulation of the very notion of sexuate difference that, on Irigaray’s reading, Heidegger’s work requires but nonetheless elides; on the other hand, Derrida’s rereading of Heidegger’s phenomenological commitments corroborates the philosophical significance of Irigaray’s intervention by recontextualizing the parameters that delimit her invocation of sexuate difference.
Ovarian tumors in relapsing acute lymphoblastic leukemia: A review of 23 cases

Abstract Five cases of relapsing acute lymphocytic leukemia (ALL) presenting as an ovarian tumor have been treated at this institution, representing the largest reported series. In a review of the literature we identified 18 additional cases of ovarian leukemic relapse. Together, these 23 patients form the basis for this report. Abdominal pain is the most common presenting symptom of ovarian leukemia. An abdominal mass is usually palpable, and at least four patients had hydronephrosis. Nine patients had documented bilateral ovarian involvement; however, bilateral disease was not a poor prognostic sign. Most ovarian relapses occurred more than 36 months after the original diagnosis of ALL, with these "late" relapsers responding more favorably to treatment than "early" relapsers. Definitive statements can not be made from a retrospective review of 23 case reports; however, salpingooophorectomy had no obvious advantage over simple biopsy, and there was no obvious advantage to the routine use of radiation therapy. Most fallures in treating ovarian leukemia occurred within 2 years. Most failures were systemic rather than local, illustrating the need for aggressive multiagent systemic chemotherapy. Survival after ovarian leukemic relapse is possible, with eight of the 23 patients alive and in complete continuous remission following the ovarian relapse (median follow-up since relapse, 42 months; range, 2 to 135+ months). With the use of more intensive chemotherapy in recent protocols, the frequency of ovarian leukemic relapses appears to be decreasing. At this institution, no child with ALL diagnosed in the 1980s has subsequently developed an ovarian relapse.
Microbands and microtwins associated with impact craters in copper and brass targets: the role of stacking fault energy

Abstract Deformation microbands coincident with {111} slip planes are observed to be associated with impact craters in large-grain (0.8 mm) copper (stacking fault energy [SFE] 80 mJ/m2) while microtwins coincident with {111} slip planes are observed in large-grain (∼1.1 mm) brass (70 Cu–30 Zn; SFE ∼10 mJ/m2). Taken together with other impact crater studies, there is solid evidence for a strong influence of SFE in the microband–microtwin transition.
Contrast enhancement of fission fragment tracks for automatic counting by image analyzing microscopes

Abstract A method of fission track staining was developed to enhance their contrast relative to background damage on polycarbonate detectors exposed to high neutron fluences (> 5 × 10 16 ). This method significantly improves fully automated track counting by image analyzing microscopes.
Transient Gratings In Wide Band Gap Semiconductors -Impurities And Optical Phonon Dynamics-

Picosecond degenerate and nondegenerate transient gratings in wide band gap crystals are reviewed. The concepts focus on how these transient gratings can be used as spectroscopic tools to investigate the dynamics of photogenerated electron-holes to impurities in ZnSe:Cu, and coherent optical phonons. The nondegenerate moving transient grating method is used to generate Raman spectra of LiNbO3 and CaCO3 spanning 2000 cm-1 in a single 30 ps. pulse. A new real time phonon dynamic technique using these gratings in conjunction with a streak camera is discussed. This technique is used to measure the dephasing of the coherent optical phonons in CaCO3 of 7.5 ps. and LiNbO3, with a temporal resolution of 2 ps.
Radiographic and manometric correlation in achalasia with apparent relaxation of the lower esophageal sphincter.

We compared the clinical, radiographic, and manometric findings in 10 patients with atypical achalasia showing complete lower esophageal sphincter (LES) relaxation to 39 patients with classic achalasia (i.e., incomplete LES relaxation). Those with atypical achalasia were younger (46.1 vs 60.6 years), had dysphagia of shorter duration (18.7 vs 45.7 mos), had lost less weight (8.2 vs 21.5 lbs), and had less esophageal dilatation (2.8 vs 3.9 cm). However, the mean LES pressures (34.5 vs 37.7 mmHg) and the esophagogastric junction calibers (4.5 vs 4.8 mm) were similar. Radionuclide esophageal emptying studies were done in 15 patients (6 with atypical achalasia; 9 with classic achalasia) and were abnormal in all. Most patients in both groups (90 and 92%) responded well to pneumatic dilatation. We conclude that achalasia with apparent LES relaxation may represent an early form of this motor disorder and that the radiographic findings remain characteristic except for less dilatation of the esophagus.
Bilayer coatings that produce a 90 ° differential reflection phase shift at oblique incidence: all possible solutions

For a system that consists of a transparent bilayer on an absorbing substrate of known optical properties, we determine all possible combinations of the thicknesses of the two layers such that the differential reflection phase shift between the p and s polarizations Δ = ± 90 ° for monochromatic light incident at a given angle θ. A ZnS-ThF4 bilayer on a Ag substrate at 3.39 μm wavelength is considered as an example of a high-reflectance system. Constant principal-angle contours are presented in the plane of the normalized thicknesses of the two films. Four distinct bilayers on Ag make ¦Δ¦ = 90 ° and equalize the reflectances for the p and s polarizations at θ = 65 °, he realize an ideal quarter-wave retarder (QWR). The QWR with the thinnest bilayer has the lowest sensitivity to incidence angle and wavelength shifts. A second example is that of a Si3N4-SiO2 bilayer on Si at 633 nm wavelength. The results in this case are of interest in relation to the four-detecior photopolarimeter, and also for principal-angle ellipsometry on this technologically important material system.
Acid phosphatase and beta-glucuronidase activities of thymus and spleen of rats after whole-body x-irradiation.

Acid phophatrase and L beta -glucuronidase activities of thymus and spleen from rats after whole-body x irradiation were studied. The increases found in specific activities 24 and 48 hours after a single dose of 200 r and 1000 r could be interpreted on the basis of a selective nitrogen retention in the tissues after radiation, but the increase of acid phosphatase activity in the thymus and spleen 2 hours after 1000 r remained unexplained. The percentage of free activities of these 2 enzymes did not seem to be affected by radiation. (auth)
El corregidor de indios, la corrupción y el estado virreinal en Perú, 1580-1630

En epoca reciente, los historiadores han empezado a reexaminar la funcion del Estado colonial en la direccion de las relaciones politicas, economicas y sociales del Imperio espanol en America. En el caso del Virreinato del Peru, gran parte del interes se ha centrado sobre la administracion de Francisco de Toledo (1569–1582), principal arquitecto de los sistemas administrative, laboral y fiscal del reino durante los anos formativos del siglo xvi. Des-de su llegada a Peru en 1569, Francisco de Toledo procuro establecer cierto orden en aquel turbulento virreinato, incrementando el poder del Estado con objeto de reestructurar las relaciones entre espanoles y amerindios, y canalizar hacia Espana el flujo de riqueza economica excedente. Algunos estudios recientes sobre el periodo de Francisco de Toledo se han apartado del analisis de los cambios legales e institucionales atribuibles al virrey, para fijarse en el impacto socioeconomico de sus reformas. Un aspecto que los historiadores no han tratado todavia con la atencion debida, sin embargo, es el papel que desempenaron el fraude y la incompetencia burocraticos en la evolucion general del Estado colonial bajo Francisco de Toledo.
Modulation of multidrug resistance gene expression by dexamethasone in cultured hepatoma cells.

Considerable evidence has accumulated indicating that overexpression of P-glycoproteins encoded by the multidrug-resistance (mdr) genes is responsible for the development of collateral resistance to a number of structurally and functionally dissimilar cytotoxic compounds in animal cells. There are three mdr genes (mdr1, mdr2, and mdr3) in the mouse genome and two (MDR1 and MDR2) in the human genome; however, only two mouse genes (mdr1 and mdr3) and one human gene (MDR1) can confer multidrug resistance upon transfection into otherwise drug-sensitive cells. Using RNase protection assay we report here that the steady-state levels of mdr1 and mdr3 messenger RNA were elevated in mouse hepatoma cells treated with dexamethasone (Dex); whereas no induction of mdr2 gene was found. Western blot analyses using anti-mdr1 and anti-mdr3 antibodies revealed that the encoded proteins appeared to be increased, but at much reduced levels. The induction was time and Dex concentration dependent. Nuclear run-on experiments de...
Influence of competing adsorbates on the underpotential deposition of copper on Pt(111)

Abstract We present a survey of the voltammetry for the underpotential deposition (UPD) of copper from aqueous sulfuric acid solution on a flame annealed Pt(111) electrode pretreated with or in the presence of aqueous solutions of a variety of adsorbales: because of its sensitivity to the presence of competing adsorbales, variations in the Cu UPD voltammetric features are used to infer substrate / adsorbate interactions. The adsorbales studied included both ionic and molecular species and were: sulfate, cyanide, thiocyanate and cis-1,2-dicyanoethylene-1,2-dithiolate anions; dimethylformamide (DMF), acetonitrile, dimethylsulfoxide (DMSO), pyridine (from 0.1 M H2SO4 and PDW (pyrolytically distilled water)); formic acid, acetic acid, hydroquinone (HQ); pyrocatechol, 2,2 - bipyridyl (0.1 M H2SO4 and PDW), 4,7-dihydroxy-1,10-phenanthroline, and 1,3-propanedithiol. Anionic adsorbates caused a diminution in the underpotential shift (relative to that in sulfuric acid alone), dependent on the strength of adsorption of the anion. Neutral adsorbales gave a variety of responses in terms of underpotential shifts and generally produced changes in the voltammetric peak shapes. Sulfur containing ligands gave rise to the most dramatic effects, generally causing a large reduction in the underpotential shift and in some cases (e.g. propanedithiol) complete inhibition of the UPD process. DMSO, acetonitrile, and DMF did not appreciably affect the potential of UPD but caused substantial kinetic effects in terms of variations in peak heights and widths. For adsorbates that could undergo protonation (e.g. pyridine, bipyridine and dihydroxy phenanthroline) the observed behavior was strongly dependent on pH, reflecting the fact that protonation of the nitrogen can lead to profound alteration in the mode of binding. Deposition in the presence of formic or acetic acid suggests the presence of discrete coexisting domains.
Seductions of an Underdevelopment Trap: Systemic Impediments to Agricultural Reform in Russia

Despite ambitious agricultural reforms initiated by the federal government, inefficient and unprofitable producers predominate in post-Soviet Russia. However, in some regions, a more robust restructuring has taken place. Observing two Russian regions - one with substantially restructured agricultural production and one in which Soviet-style coordination predominates - we develop a model of the interactions between political and economic incentives that lead to these divergent outcomes. The model identifies region- and sector-specific characteristics that, while encouraging some regional governments to maintain Soviet-style redistribution structures and make producers forsake more efficient outcomes as more costly, push other regions to pursue reform.
New Taxa of Erythroxylum (Erythroxylaceae) from the Venezuelan Guayana

Erythroxylum foetidum Plowman,E. guanchezii Plowman, andE. macrophyllum Cav. var.savannarum Plowman are described and illustrated, and their taxonomic and phytogeographic relationships are discussed.
A magnetic tape interface for nuclear data 130 multichannel analyzer and Kennedy 1400 tape transport

Abstract A digital electronic interface to link a Kennedy 1400 tape transport to a Nuclear Data 130 multichannel analyzer has been built and tested.
Security in graphs

Let G=(V,E) be a graph. A set S@?V is a defensive alliance if |N[x]@?S|>=|N[x]-S| for every x@?S. Thus, each vertex of a defensive alliance can, with the aid of its neighbors in S, be defended from attack by its neighbors outside of S. An entire set S is secure if any subset X@?S can be defended from an attack from outside of S, under an appropriate definition of what such a defense implies. Necessary and sufficient conditions for a set to be secure are determined.
Information reporting and tax compliance: An investigation using individual TCMP data

Empirical studies of tax compliance have typically used data aggregated by audit class to analyze the impact of federal income tax and enforcement structures on the individual's compliance decision. This paper uses micro data from individual tax returns audited during the 1971 cycle of the Internal Revenue Service's (IRS) Tax Compliance and Measurement Program to reexamine the determinants of tax compliance. IRS data have also consistently revealed marked differences in voluntary reporting rates across different types of income. These differences may be driven by differential information reporting requirements. Hence, separate compliance equations are estimated for income subject to third-party information reporting and for all other income. The results show third-party information reporting to be an effective deterrent to noncompliance, but cast doubt on the presumption that lower marginal tax rates led to greater compliance.
New method for rapid blood gas determination without blood sample.

Abstract A new method of blood gas determination has been developed. It does not depend upon polarographic technics which are the basis of most currently used blood gas analysers. Because of this, it needs only one calibration and remains stable after that. It can monitor and display blood gases continuously or transmit the results to a nursing station. The blood gas read-out may also be used to trigger a feedback loop or an alarm for thresholds of high or low oxygen. It is very versatile and may be used to compare expired air to arterial blood or to monitor and adjust the level of oxygen in an incubator or respirator. Clinical trials await further minor modifications in the design of the flush gas system and in the method of maintaining a nonthrombogenic surface within the silicone shunt tube.
A phase I trial of weekly paclitaxel, 13- cis-retinoic acid, and interferon alpha in patients with prostate cancer and other advanced malignancies.

Purpose Based on prior studies demonstrating the effect of 13-cis-retinoic acid and interferon alpha (CRA/IFN) in decreasing the expression of the antiapoptotic protein bcl-2, our prior clinical study of CRA/IFN with paclitaxel (TAX) administered every 3 weeks, and data demonstrating increased activity of weekly TAX against prostate cancer, we designed a phase I study of weekly TAX in combination with CRA/IFN in patients with prostate cancer and other advanced malignancies. To develop a marker of drug effect, we assessed bcl-2 downregulation in patient peripheral blood mononuclear cells (PBMC).
Parametric Study of Turbulent Separated Convection Flow Over a Backward-Facing Step in a Duct

Simulations of turbulent convection flow adjacent to a two dimensional backward-facing step are presented to explore the effects of step height, step inclination angle, a mounted rib and Prandtl number on velocity field and heat transfer. Reynolds number and duct’s height downstream from the step are kept constant at Re0 = 28000 and H = 0.19m, respectively. Uniform and constant heat flux of qw = 270W/m2 is specified at the stepped wall downstream from the step, while other walls are treated as adiabatic. The selection of the values for these parameters is motivated by the fact that measurements are available for this geometry and they can be used to validate the flow and heat transfer simulation code. The simulated results compare very well the measurements. The primary and secondary recirculation regions increase in size as the step height increases. The friction coefficient becomes smaller in magnitude with the increase of the step height. The peak Stanton number becomes smaller as the step height increases. The reattachment location becomes longer as the step inclination angle increases. With increase of the step inclination angle, the secondary recirculation region disappears. The peak friction coefficient inside the primary recirculation region becomes smaller as the step inclination angle decreases. Installation of a baffle on the upper wall causes the primary recirculation region to become smaller. The Stanton number decreases as the Prandtl number increases.Copyright © 2007 by ASME
Viscoelastic behavior of polybutadienes with high 1,4-microstructure and narrow molecular weight distribution

Polybutadienes (PBs) of narrow molecular weight distributions with high 1,4-microstructure were synthesized by sec-butyllithium-initiated, living polymerization. The shoulder-like anomalous behavior of the storage modulus G′(ω) in the terminal zone for PBs was studied using size exclusion chromatography (SEC) and rheometric mechanical spectrometry (RMS). It was found that a high-molecular-weight fraction in the PBs was the main reason for the occurrence of the shoulders. The linear viscoelastic spectra were successfully obtained by the Pade–Laplace method from experimental dynamic data, using either the dynamic storage, G′(ω), or loss, G"(ω), modulus. Both the dynamic moduli and stress relaxation in the linear regime were then calculated with reasonable precision. The feasibility of time–temperature–molecular weight superposition for PBs using this method was demonstrated. The dependencies of relaxation spectra on temperature and molecular weight were obtained by a fitting procedure. Thus, with a known reference state, the relaxation spectrum for a given molecular weight PB at a given temperature can be predicted. The predicted dynamic moduli are in good agreement with experimental data. © 1999 John Wiley & Sons, Inc. J Appl Polym Sci 71: 1315–1324, 1999
Effects of prepregnancy ethanol on neuromotor development, activity, and learning.

Abstract This study examines the behavioral consequences of both long-term chronic and acute high-dose administration of ethanol before pregnancy. Female rats were assigned to one of five conditions: a self-administered liquid diet with 35% ethanol-derived calories, a pair-fed liquid diet with 0% ethanol-derived calories, a gavage intubation with 4 g/kg ethanol, a gavage intubation control, or a standard lab chow control. Offspring were weighed at various ages and tested for neuromotor development, activity, and learning a Morris maze water task. Offspring of mothers in the high-dose condition were hyperactive as iuveniles but not as adults. Hyperactivity was not seen in the low-dose chronic ethanol condition, contrary to previous reports. Neither ethanol administration paradigm was associated with learning deficits. Prepregnancy stress effects were apparent from both the restricted liquid diet feeding and the gavage treatment on neuromotor development. A possible mechanism for the effects of prepregnancy ethanol treatment is linked to ethanol's potential to alter hormone levels. Since hormones are directly responsible for the maturation of the egg, hormonal imbalances as a result of ethanol exposure may result in developmental deficiencies in the offspring.