cssi/SciSciGPT-SciSciNet huggingface dataset:
Growth, structure and thermal properties of chromium oxide films on Pt(111)

Abstract We have prepared chromium oxide films on Pt(111) with thicknesses ranging from less than a monolayer to more than eight monolayers. The films were grown by Cr vapor deposition under an oxygen background pressure of 2 × 10 −6 mbar and a sample temperature of 600 K. The growth, structure and thermal properties of the resulting overlayers have been studied using a combination of ISS, XPS, LEED and STM. During the initial stage of growth, the film nucleates at Pt step edges, and grows in a step-flow mode. For the first two monolayers, a well-ordered p(2 × 2) structure is observed and attributed to the epitaxial growth of metastable Cr 3 O 4 . At higher coverage, a (√3 × √3)R30° structure appears, due to the formation of the stable Cr 2 O 3 phase. After heating in vacuum to about 700 K, the p(2 × 2) film begins to decompose and agglomerate, and finally becomes a (√3 × √3)R30° overlayer. The latter is stable up to the highest temperature used in these studies (1000 K), although at this temperature it also shows dewetting and further clustering.
Self assembled polynuclear [3×3] grids — structural and magnetic properties of Mn(II), Fe(III), Co(II), Ni(II) and Cu(II) complexes with M9(μ2-O)12 cores

Abstract A series of polynuclear [3×3] square grid complexes of Mn(II), Fe(III), Co(II), Ni(II), and Cu(II) is reported from the high yield self assembly reactions of the linear tritopic ligands H 2 L3 and H 2 L4 and appropriate metal salts. Structural data reveal a complementary matching of the ligand coordination pockets and the coordination requirements of the metal ions in the [3×3] square M 9 (μ 2 -O) 12 , alkoxide bridged grids found in [Mn 9 (L3) 6 ](ClO 4 ) 6 ·18H 2 O, [Mn 9 (L4) 6 ](NO 3 ) 6 ·12H 2 O and [Cu 9 (HL3) 6 ](NO 3 ) 12 ·9H 2 O. Similar structural types are implicated for analogous Ni(II), Co(II), and Fe(III) complexes. The structural and magnetic properties are discussed. The Cu 9 grid system exhibits both intramolecular ferromagnetic and antiferromagnetic coupling, and has an S =7/2 ground state. A similar situation appears to exist for the analogous Fe(III) 9 complex, with a spin ground state approaching S =29/2. The Mn(II) 9 , Ni(II) 9 and Co(II) 9 complexes exhibit intramolecular antiferromagnetic coupling.
Two-photon emission processes in electron-atom interactions

Abstract We will describe the experimental techniques and preliminary results of an on-going three-parameter coincidence experiment in which two-photon spectra are obtained by electron bombardment of target foils of selected thicknesses. The atomic number of the foils ranges from Z = 26 to 82. Incident electrons have been provided both by the β spectrum of a 147 Pm source and by a 50–150 keV electron beam from an accelerator. Processes considered to date include: double bremsstrahlung, double innershell ionization, and coherent emission of both a characteristic and a continuum X-ray. The cross sections for these two-photon processes are much smaller than the processes that produce single photons in the target. This can lead typically to a large accidental rate in the accelerator experiment, or accentuate the need for a target thickness study of the real rate in the source experiment where thicker targets have been used to increase the statistics.
Dynamics of adaptation and diversification: a 10,000-generation experiment with bacterial populations

We followed evolutionary change in 12 populations of Escherichia coli propagated for 10,000 generations in identical environments. Both morphology (cell size) and fitness (measured in competition with the ancestor) evolved rapidly for the first 2000 generations or so after the populations were introduced into the experimental environment, but both were nearly static for the last 5000 generations. Although evolving in identical environments, the replicate populations diverged significantly from one another in both morphology and mean fitness. The divergence in mean fitness was sustained and implies that the populations have approached different fitness peaks of unequal height in the adaptive landscape. Although the experimental time scale and environment were microevolutionary in scope, our experiments were designed to address questions concerning the origin as well as the fate of genetic and phenotypic novelties, the repeatability of adaptation, the diversification of lineages, and thus the causes and consequences of the uniqueness of evolutionary history. In fact, we observed several hallmarks of macroevolutionary dynamics, including periods of rapid evolution and stasis, altered functional relationships between traits, and concordance of anagenetic and cladogenetic trends. Our results support a Wrightian interpretation, in which chance events (mutation and drift) play an important role in adaptive evolution, as do the complex genetic interactions that underlie the structure of organisms.
Structures of PhX (X O and N). Importance of polarization functions in the basis set

Abstract The structures of the ground state phenoxy radical and phenylnitrene were calculated by the UNO-CAS method and compared with CAS-SCF results. The two methods produce almost identical structures which are very sensitive to polarization functions in the basis sets. On going from the 3–21G to the 6–31G* basis set, the CO and CN distances decrease significantly. Further enlarging the basis set from the 6–31G* to the 6–311G(2d, p) has minor effect on the calculated structures. These results indicate that for the correct description of the title compounds, a basis set of at least double zeta plus polarization quality is needed, and one should be cautious about predictions derived from single point calculations on structures obtained with the 3–21G basis set.
Zener tunneling in semiconductors

Abstract The Zener current in a constant field is calculated both with and without the W annier -A dams reduction of the interband-coupling terms. The Zener current is only slightly different in the two cases, a fact which has already been noted by W annier . The apparent reduction of interband coupling is interpreted as a polarization correction. A detailed calculation of the Zener current is made for a simple two-band model which is applicable to InSb. The evaluation of the tunneling integral follows closely a calculation due to K eldysh .
The synthesis of some derivatives of saccharin

A number of saccharin, 6-nitrosaccharin, and 6-aminosaccharin derivatives were prepared for pharmacological screening and evaluation as potential local anesthetics. The saccharin derivatives include the 2-ethyl, 2-n-propyl, 2-allyl, 2-n-amyl, 2-(β-diethylaminoethyl), 2-(β-dimethylaminoethyl), 2-(β-di-n-butylaminoethyl), and 2-(γ-diethylaminopropyl) saccharins. The 6-nitrosaccharin derivatives include the 2-ethyl, 2-n-propyl, 2-allyl, and 2-n-amyl 6-nitrosaccharins. The 6-aminosaccharin derivatives include the 2-ethyl, 2-n-propyl, and 2-allyl 6-aminosaccharins. The nonsubstituted saccharin derivatives were tested for local anesthetic activity and were found to possess only a very low order of activity both toxically and subcutaneously. It may be of interest to note that these saccharin derivatives had no sweet taste and, in many instances, possessed an intensely bitter taste.
Degradation effects of dilute polymer solutions on turbulent friction and heat transfer behavior

Abstract Long-term degradation tests for dilute polymer solutions flowing turbulently in circular pipes were conducted in a closed recirculatory flow loop at room temperature. The polymeric additives used were Polyox WSR-301 and Separan AP-273 at 200 ppm wt. in deionized water. The degradation run for Separan was conducted for 730 h, which is considerably longer than any of the earlier degradation studies reported in the literature. The degradation run for Polyox was conducted for only 22 h because of the extreme sensitivity of Polyox to shear degradation. Effects of degradation on turbulent friction and heat transfer coefficients are presented. It was found that dilute Polyox solution cannot be used in recirculatory systems because it degraded completely in less than 24 h. However, dilute Separan solution did not degrade completely under a typical flow shear condition but maintained a plateau value of about 25% friction reduction after the initial rapid degradation period. The existence of a plateau for the dilute Separan solution is an important finding because it implies that this solution may be a good candidate for use in practical closed-loop thermal systems.
US physicians' perceptions of the effect of practice guidelines and ability to provide high-quality care.

Objectives: In the USA, health care organizations frequently disseminate practice guidelines to physicians, but physicians often resist implementing guidelines when they perceive no improvements in quality of care will result. Greater involvement with a single health care organization may affect physicians' perceptions of guidelines. We examined the relationship between the perceived effect of guidelines on practice and perceived quality of care for US primary care physicians (PCPs) and specialists with varying levels of financial involvement with a single managed care organization.Methods: Data were from the 1996-1997 Community Tracking Study, a nationally representative, cross-sectional survey of 12,528 physicians. Data were adjusted for possible confounders using ordinal logistic regression.Results: Almost half the physicians described a moderate to very large perceived effect of guidelines (46% of PCPs, 46% of specialists). Physicians' financial involvement with a single organization was modest: PCPs ...
The ALT-II data acquisition and display system

Abstract This paper describes the data acquisition, analysis, and graphics display system developed for the ALT-II toriodal belt pump limiter experiment on the TEXTOR tokamak. The general layout and control of the serial CAMAC data serial highway serving the various diagnostics is given. In addition, key features of the data processing network which provide flexibility and compatibility between the data analysis and display programs are emphasized. Data reduction program considerations relevant to edge plasma diagnostics used with ALT-II and other controlled fusion experiments are included.
Can Educational Policy Equalize Income Distribution

Martin C.arnoy (United States of America). Professor of Education, Stanford University. Specialist in the economic* of education, economic development and political economy. Among his many publications in related fields are Education as Cultural Imperialism, Economic Change and Educational Reform in Cuba, I955-I974~ and Education and Employment. It was not long ago that most leaders and planners in market economies believed that the solution to poverty lay in a rapid expansion of economic output. Two factors have made that solution obsolete: it was much more difficult than imagined to increase output; and, even in those economies with rapidly increasing per capita income statistics, the poorest half of the population did not fare signilicandy better. Leaders and policy-makers once viewed education as a key variable in expanding output and solving poverty. They thought that by raising the literacy rate and increasing the number of years of schooling in the labour force, economic and social development would follow rapidly. Market economies around the world expanded their educational systems, but economic development did not necessarily occur. Many countries now have a much more schooled labour force and higher income per capita than in the I95OS, but extreme poverty for the mass of their population and high unemployment continue unabated. A new feature has been added: the level of education of the unemployed has risen substantially. Under these conditions, leaders and planners gradually realized that economic growth alone would not solve the problem of poverty rapidly enough to meet internal political pressure. The distribution of output became, at the beginning of this decade, a crucial development variable. Again, education is to play a key role in redistributing income, just as it did in the growth process. But while the logic of education's relation to growth is tightly knit by the human capital model--though the economic pay-off to human capital investment
Numerical methods for eigensystems: the Orr-Sommerfeld problem as an initial value problem

Abstract A recently proposed computational method for analyzing linear ordinary differential eigensystems in which a single initial value problem is used is compared with the usual methods that require more than one initial value problem the linear independence of whose solutions must be maintained. Since the new method requires only one initial value problem difficulties with parasitic error are avoided and eigenvalues for stiff systems can be obtained using standard integration schemes without resorting to techniques such as orthonormalized integration. Examples consist of a test problem with adjustable stiffness and the Orr-Sommerfeld equation for plane Poiseuille flow.
Distribution of intravascularly injected lanthanum ions in ganglia of the autonomic nervous system of the rat

Intravascular injection of lanthanum revealed that tight junctions of capillaries in sympathetic ganglia are impermeable to small ions and thus behave like capillaries of the blood-brain barrier. The failure of lanthanum to accumulate in the extracellular space suggests that fenestrated capillaries are not as ion-permeable as use of horseradish peroxidase (HRP) by some authors has indicated. A possible toxic action associated with high concentrations of HRP may be responsible for the high permeability of this substance. Testing with lanthanum demonstrated that sympathetic ganglia possess anatomic features that provide a hematic barrier. The blood-ganglion barrier resembles, but has not yet been demonstrated to be as absolute as the blood-brain barrier.
Drug binding by branched DNA: selective interaction of the dye stains-all with an immobile junction.

The thiacarbocyanine dye Stains-All (4,5:4',5'-dibenzo-3,3'-diethyl-9-methylthiacarbocyanine bromide) is one of a large number of cyanine dyes introduced as photosensitizers in the photographic industry. Stains-All is used in histology as a stain for nucleic acids, proteins, polysaccharides, and lipids. We report here that the dye colors branched DNA molecules differently from linear duplexes and use footprinting experiments with methidiumpropyl-EDTA-Fe(II) [MPE.Fe(II)] and bis(o-phenanthroline)copper(I) [(O-P)2Cu(I)] to show that Stains-All interacts preferentially at the branch point of a four-arm DNA structure. A titration experiment allows us to estimate that the interaction of the dye with the branch has a dissociation constant below 45 nM, tighter than that of ethidium or methidium by over 2 orders of magnitude. Probing the interaction with the purine-specific reagent diethyl pyrocarbonate (DEPC) implies that the dye induces an asymmetric distortion near the branch in the major grooves of double helix in the junction.
Using KCl to determine size at competence for larvae of the marine gastropod Crepidula fornicata (L.)

Abstract Competent larvae of the marine gastropod Crepidula fornicata (L.) were induced to metamorphose (i.e., lose the velum) by elevating sea-water [KCl] by 5–50 mM. The response was optimal at 15–20-mM elevations, at which 50% metamorphosis was obtained in ≈1125 μm shell length metamorphosed in response to increased [KCl]. Rearing temperature may affect the size at which larvae of this species become responsive to K+. CaCl2 (20-mM concentration elevations), GABA (4×10−7, 4×10−6 M), and NaCl (10–20-mM concentration elevations) generally failed to trigger metamorphosis. Twenty-mM elevations of [RbCl] and [CsCl] induced 100% metamorphosis but the juveniles were immobile and died after several days. Elevating [KCl] appears to be a reliable way to assess competence and trigger metamorphosis in larvae of C. fornicata.
Effects of Dietary Selenium on UVB-Induced Skin Carcinogenesis and Epidermal Antioxidant Status

Abstract Low plasma selenium levels have been linked to increased risk of non-melanoma skin cancer in humans. The present study examined the relationship between selenium level in the diet and development of skin tumors induced by ultraviolet radiation in female Skh:HR-1 hairless mice. Animals were maintained on a torula yeast-based diet containing either 0, 0.1, or 0.5 mg/kg selenium as Na 2 SeO 3 . Ultraviolet light at a dose of 90 mJ/cm 2 , three times weekly for 20 weeks, resulted in skin tumors in all groups. Following cessation of ultraviolet light exposure, tumors continued to increase in selenium-deficient mice and those fed only 0.1 mg/kg, but leveled off for those on 0.5 mg/kg. During the carcinogenesis process, epidermal antioxidant enzymes catalase, superoxide dismutase, and glutathione peroxidase were monitored. Selenium deficiency decreased glutathione peroxidase and resulted in an early increase in superoxide dismutase and catalase in response to ultraviolet light treatment. These results indicate that dietary Se may be an important chemopreventive agent for skin cancer.
Age-related decline in central serotonin transporter availability with [123I]β-CIT SPECT

Postmortem studies have provided limited and conflicting data regarding aging effects on the central serotonin transporter (SERT). The present study investigated the effect of age on SERT availability in the human brainstem and diencephalon with single photon emission computed tomography (SPECT) using the ligand [(123)I]2 beta-carbomethoxy-3 beta-(4-iodophenyl)tropane ([(123)I]beta-CIT). Healthy control subjects (n = 126) who ranged in age from 18 to 88 were injected with 6.0 +/- 0.8 (mean +/- SD) mCi [(123)I]beta-CIT and imaged 23.1 +/- 1.9 h later under equilibrium conditions. A ratio of specific to nondisplaceable brain uptake (i.e. , V(3)" = [brainstem-diencephalon -occipital]/occipital), a measure proportional to the binding potential (B(max)/K(D)), was derived. SERT availability (V(3)") showed a significant inverse correlation with age (r = -0.40, P < 0.0001). Linear regression analysis revealed that V(3)" declined by 29.5% over the age range 18 to 88, or approximately 4.2% per decade. These results demonstrate reductions in the availability of central SERT binding sites with age in living human subjects.
Telecom-band entanglement generation in standard fibers

We review on-going progress in the development of fiber-based telecom-band entanglement sources. Two different schemes (a Sagnac-loop scheme and a counter-propagating scheme) for generating polarization entanglement are reviewed and the pros and cons of each are summarized. A new scheme, called the double-loop scheme is proposed, which is theoretically shown to be capable of combining the benefits and avoiding the pitfalls of each previous scheme.
Ethnic mobilization and reactive nationalism: The case of Moldova

1. Introduction Until the October 1991 Soviet coup, Moldova, previously known as Bessarabia and the Moldavian Soviet Socialist Republic, had known independence only briefly, having been part of the Russian Empire, Romania, or the Soviet Union for almost its entire history. As a result of shifting foreign influences and borders, Moldova, like most modern political entities, has a multiethnic population. The conflicting perspectives and demands of Moldova's different ethnic groups underlie many of today's controversies.
An electron microscope study of nebenkern formation and differentiation in spermatids of Murgantia histrionica (Hemiptera, Pentatomidae).

Mitochondria in early spermatids of many insects aggregate and form a round body, the nebenkern. The nebenkern undergoes a structural differentiation and then divides into two separate equal-sized bodies. In the present study, nebenkerns of Murgantia histrionica, a Hemipteran insect, were reconstructed using electron micrographs of serial sections to determine how the mitochondria transform into the two separate bodies. Newly formed nebenkerns are made of one piece, an anastomosis of rod-like segments. Some segments interconnect to join networks of rings. Each network interlocks with another similar network, but networks which interlock are connected with each other by other segments of the nebenkern. Later, the entire nebenkern is made of two unconnected and interlocked networks of rings. The nebenkern appears to remain bipartite during subsequent differentiation. Since the two pieces are interlocked, breaks must occur before the pieces can separate. As breaks occur, each network transforms into a set of curved sheets, producing a nebenkern made of four concentric layers. The three outer layers are each made of two curved sheets which surround a bipartite central core. The surface sheets meet at a furrow in the surface of the nebenkern; segments in each layer are roughly symmetrical with each other about the plane in which the furrow lies. Rod-like segments join alternate segments. The number of layers then decreases to three, and later, to two. These nebenkerns resemble four-layered nebenkerns, but fewer connections between alternate segments are present. The two pieces constituting the nebenkern probably separate after most of the latter connections disappear. Hypotheses to account for the observed changes in nebenkern structure are presented.
Coupled dynamics of atoms and radiation-pressure-driven interferometers

We consider the motion of the end mirror of a cavity in whose standing-wave mode pattern atoms are trapped. The atoms and the light field strongly couple to each other because the atoms form a distributed Bragg mirror with a reflectivity that can be fairly high. We analyze how the dipole potential in which the atoms move is modified due to this back action of the atoms. We show that the position of the atoms can become bistable. These results are of a more general nature and can be applied to any situation where atoms are trapped in an optical lattice inside a cavity and where the back action of the atoms on the light field cannot be neglected. We analyze the dynamics of the coupled system in the adiabatic limit where the light field adjusts to the position of the atoms and the light field instantaneously and where the atoms move much faster than the mirror. We calculate the sideband spectrum of the light transmitted through the cavity and show that these spectra can be used to detect the coupled motion of the atoms and the mirror.
The control motive and marital violence.

The role of the control motive in marital violence is examined using data on current and former marriages from the Survey of Violence and Threats of Violence Against Women and Men. The findings indicate no support for the position that husbands engage in more marital violence than wives because they are more controlling. In former marriages, we observe statistical interactions between gender and control: former husbands who were controlling or jealous were particularly likely to be verbally aggressive and to engage in violence. The controlling husbands (present and former), however, are not particularly likely to engage in violence that is frequent, injurious, or unprovoked. The evidence suggests that husband and wives may differ in their methods of control but not their motivation to control. An erratum for this article was reported in Vol 22(6) of Violence and Victims -- In the article, the data points for male and female partners are misidentified in Figure 1 (p. 398). They should be reversed: The male partner data points (indicated by triangles) are actually the female partner data points, and the female partner data points (indicated by squares) are actually the male partner data points. Language: en
On a class of nilpotent table algebras and applications to association schemes

In this paper we present sufficient conditions under which a nilpotent table algebra is exactly isomorphic to the wreath product of thin table algebras, and show by examples that this result is not true when the conditions are replaced by weaker ones. Applications to association schemes are also discussed.
Cellular Signaling and Protein−Protein Interactions Studied Using Fluorescence Recovery after Photobleaching†

Transduction of intracellular signals requires multiple protein−protein and cellular structure interactions. These interactions affect the mobility of the involved proteins; therefore mobility meas...
The Impact of Abuse History and Trauma Symptoms on Successful Completion of a Prostitution-exiting Program

This study examines the trauma symptoms and life experiences of 49 women in a residential prostitution-exiting program and identifies differences among women who complete 90 days of the program and women who drop out of the program prior to completing 90 days. The majority of the women reported childhood abuse, adult abusive relationships, and victimization. Women who completed 90 days of treatment were found to be older than the non-completers. Non-completers were more likely to report clinically significant trauma symptoms including dissociation, poor coping behaviors, sex-related issues, and dysfunctional sexual behavior than completers. These findings suggest the importance of incorporating trauma-focused intervention early in the services provided in the exiting programs as well as the need to address the traumatic symptoms related to childhood and adult trauma histories. Findings also indicate the importance of clinically addressing trauma-related sexual issues, concerns, and behavior.
Does water harvesting induce fertilizer use among smallholders? Evidence from Ethiopia

Rainfall shortage is a major production risk for smallholder farmers. Due to rainfall shortage, smallholders limit the use of modern inputs such as fertilizer and improved seeds. This study investigates if water harvesting technologies (WHTs) induce fertilizer use and whether there is joint adoption of fertilizer and water harvesting technologies. Using panel data collected from Ethiopian farmers in two regions in 2005 and 2010, a random effects probit model and a bivariate probit model are estimated to investigate these two issues. Both models include variables that are hypothesized to affect fertilizer and WHT use. The findings indicate that: (1) water harvesting increases the probability of using fertilizer; (2) past WHT use positively affects the probability of current fertilizer use but past fertilizer use does not affect current WHT use; (3) total landholding, farm capital, and education significantly increase the probability of fertilizer use whereas the price of fertilizer and distance to market decrease the probability of fertilizer use; (4) there are significant regional and yearly differences in fertilizer use; and (5) growing perennial crops, and distance from natural water sources increase the probability of using water harvesting in 2010 whereas distance from markets, age and altitude decreases it. These results imply that measures encouraging water harvesting can also lift low fertilizer use among Ethiopian smallholders.
Government credibility and policy choice: evidence from the Pennsylvania earned income tax

Abstract This paper considers the decision of Pennsylvania communities whether to levy a 1% wage tax. While a simple political economy model suggests this tax should be enacted when many residents are exempted from the tax, the opposite pattern seems to hold. One explanation is that residents may mistrust their government and fear that the new tax monies will be spent unwisely. Several implications of this credibility story are consistent with the data, and non-taxing communities tend to have low credibility (as measured by three proxies). In addition, after controlling for credibility the proportion of exempt residents is positively associated with the probability of enacting the wage tax just as the political economy model suggests.
Process and Product: A Review of the Research on LD Children's Writing Skills:

In the last decade we have witnessed a renewed interest in writing research and instruction in both regular and special education. Although regular education researchers have moved away from a product focus, instead examining the writing process, many contend that special education research has continued to focus on product errors while neglecting the processes involved in composition and spelling. This article contains a review of the writing research literature published during the last five years. Both composition and transcription studies conducted with elementary-aged LD subjects were examined. Conclusions of the studies as well as their implications for writing instruction and research are discussed.
Memory for information about persons: the effect of encoding operations on subsequent retrieval

Three experiments designed to test the hypothesis that list length effects are a function of encoding as well as retrieval processes are reported. Subjects in Experiment 1 were presented with a list of behaviors, each of which had been ostensibly performed by one of two target persons. Subjects attempting to learn the information as well as possible manifested strong between-category and within-category list length effects. However, subjects who expected to interact with one of the targets at a later time manifested only within-category list length effects. Experiment 2 demonstrated that when the list contained two categories (nouns and adjectives), but all of the informatioin pertained to a single target person, both orienting tasks produced both types of list length effects. Experiment 3 demonstrated that the two types of list length effects are also affected by encoding operations when subjects learn unrelated lists of words. The results are discussed in terms of their implications for the recent SAM model.
The study of KCl-CuCl eutectic fused salt as a potential intermediate temperature heat transfer and storage medium

Abstract A preliminary investigation of the KCl-CuCl eutectic mixture as a potential broad temperature range ( 150 to > 800° C ) heat transfer and storage medium indicated that this eutectic composition may be superior to other high temperature fluids. Density, viscosity, heat capacity, heat of fusion, melting point, compatibility and thermal stability were examined. Based on these preliminary results, it is reasonable to expect operating temperature capabilities from the melting point to in excess of 800°C.
Caterpillar thermal adaptation: Behavioral differences reflect metabolic thermal sensitivities

1. 1. Eastern tent caterpillars (Malacosoma americanum) regulate their body temperatures while gypsy moth caterpillars (Lymantria dispar) are thermal conformers. 2. 2. Resting metabolism of the former is strongly temperature dependent while that of the latter is thermally independent at normal daytime ambient temperatures. 3. 3. Despite different physiological responses and behavior, both species operate at similar metabolic levels over varying diurnal air temperatures. 4. 4. Thermal sensitivity of resting metabolism was closely related to the thermal sensitivity of growth for these species reared at constant temperature.
Patterns of age- and sex-specific prevalence of major blood-borne infections in United States blood donors, 1995 to 2002: American Red Cross blood donor study.

BACKGROUND: The American Red Cross has been maintaining a research database of all blood donations, including all testing results for infectious disease markers, since 1995. This study analyzes the temporal trends of major blood-borne infections among blood donors. STUDY DESIGN AND METHODS: Temporal trends for age- and sex-specific prevalence of human immunodeficiency virus (HIV), hepatitis B virus (HBV), hepatitis C virus (HCV), and syphilis infections in US blood donors were analyzed based on linear trend or time series model or other models as appropriate. RESULTS: From 1995 to 2002, significant declines have been observed for infections that used to be at relatively higher levels. Declines in prevalence were slower among first-time donations than repeat donations. There was an increase in prevalence of anti-HCV among first-time male donors of 50 to 59 years of age. Anti-HIV prevalence appeared to have increased among first-time male donors of 30 to 39 years of age since 2000. CONCLUSION: Different sex and age groups showed various patterns of decline and even signs of increase. The increasing prevalence among some age and sex groups may merit further investigation.
Effect of blunt trailing edge on rotor broadband noise

The production of high-frequency broadband noise by turbulent vortex shedding from rotor blades with blunt trailing edges is investigated analytically. The derivation of the governing equations, analogous to that of Kim and George (1982) for boundary-layer/trailing-edge noise, is explained, and numerical results are compared with the experimental data of Hubbard et al. (1981) and Lowson et al. (1972) in graphs. It is shown that vortex-shedding noise is a significant component of blunt-trailing-edge rotor broadband noise and that the analytical method employed gives reasonable predictions. The need for a better empirical expression for the normalized spectrum and for more measurements of surface pressure fluctuations near blunt trailing edges is indicated.
Conformation of Myosin Interdomain Interactions during Contraction: Deductions from Proteins in Solution†

Myosin subfragment 1 (S1) is the ATP catalyzing motor protein in muscle. It consists of three domains that catalyze ATP and bind actin (catalytic), conduct energy transduction (converter), and transport the load (lever arm). These domains interface in two places identified as interface I, containing the reactive thiol (SH1) and ATP-sensitive tryptophan (Trp510), and interface II, containing the reactive lysine residue (RLR). Two crystal structures of S1 were extrapolated to working "in solution" or oriented "in tissue" forms, using structure-sensitive optical spectroscopic signals from extrinsic probes located in the interfaces. Observed signals included circular dichroism (CD) and absorption originating from S1 in solution in the presence and absence of actin and fluorescence polarization from cross-bridges in muscle fibers. Theoretical signals were calculated from S1 crystal structure models perturbed with lever arm movement from swiveling at three conserved glycines, 699, 703, and 710 (chicken skeletal myosin numbering). Structures giving the best agreement between the computed and observed signals were selected as the representative forms. Both interfaces undergo dramatic conformational change during ATPase and force development. Changes at interface I suggest the molecular basis for the collisional quenching sensitivity of Trp510 to nucleotide binding. The probe conformation at SH1 suggests how it alters S1 ATPases. At interface II, the spatial relationship of the lever arm and the extrinsic probe at RLR suggests how the probe alters S1 ATPases and that it should inhibit lever arm movement during the power stroke. The latter possibility, if true, establishes a part of the corridor through which the lever arm swings during the power stroke. Global structural changes in actomyosin are discussed in the accompanying paper [Burghardt et al. (2001) Biochemistry 40, 4821-4833].
Loss of absorptive capacity for sodium chloride as a cause of diarrhea following partial ileal and right colon resection.

Previous studies have emphasized the role of bile acid and fat malabsorption as the cause of the diarrhea that may follow ileal and right colon resection; unabsorbed bile acids and fat are believed to reduce sodium chloride and water absorption in the remaining colon. In this paper we report studies in eight patients with severe postresection diarrhea, in search of a more basic defect in sodium chloride absorption, ie, a loss of sodium chloride absorptive capacity as a direct consequence of resection of sodium chloride absorption sites. First, we determined whether or not diarrhea persisted during a 48-hr fast; in all patients diarrhea and large fecal electrolyte losses continued during a fast. Second, we measured sodium chloride and water absorption rates during total gut perfusion with a balanced electrolyte solution; compared to normal controls, the patients absorbed 23–31% less water, sodium, and chloride. In three patients who could be studied further, the absorptive defect was markedly accentuated when the perfusing solution was such that sodium chloride absorption had to take place against a concentration gradient. These observations indicate that postresection diarrhea patients have a reduced capacity to absorb sodium chloride, particularly when there is a concentration gradient between lumen and plasma. Although all of these patients had malabsorption of radiolabeled taurocholic acid, there was only a modest and statistically insignificant reduction in daily stool weight during treatment with large doses of cholestyramine, suggesting that bile acid malabsorption was not responsible for a major part of their diarrhea. We postulate that a loss of ileal and colonic absorptive capacity for sodium chloride rather than a cathartic effect of unabsorbed bile acids or fat is the major cause of diarrhea in these patients.
Abutment-free bone-anchored hearing devices in children: initial results and experience.

Abstract Objectives Bone-anchored implantable hearing devices are widely accepted as a surgical option for certain types of hearing loss in both adults and children. Most commercially available devices involve a percutaneous abutment to which a sound processor attaches. The rate of complications with such bone conduction systems is greater than 20%. Most complications arise from the abutment. Recently, the Sophono (Boulder, CO) Alpha 1, an abutment-free system, has been introduced. Study design and methods We conducted a retrospective chart review of the first five patients who underwent implantation with the Sophono abutment-free bone conduction hearing system with the Alpha 1 processor at our institution and report here on these patients’ pre- and postoperative audiometric data and clinical courses. Results Average improvement in pure-tone average was 32 dB hearing loss and average improvement in speech response threshold was 28 dB hearing loss. All patients were responding in the normal to mild hearing loss range in the operated ear after device activation. Average improvement across individual frequencies was between 17 and 37 dB (SD 5.5–11 dB). Conclusion Our audiometric results to date are promising and have been consistent with published data on other bone-anchored hearing devices.
Teacher Leadership: Practices, Politics, and Persistence

In recent years, the federal role in educational reform and policy making has steadily increased, bringing with it new priorities, initiatives, and policies. Chief among them: districts, schools, a...
Ultrastructural evidence for mu-opioid modulation of cholinergic pathways in rat dentate gyrus.

Within the rat hippocampal formation, cholinergic afferents and μ-opioid receptors (MORs) are involved in many crucial learning processes, including those associated with drug reward. Pharmacological data, and the overlapping distributions of cholinergic and μ-opioid systems, particularly in the dentate gyrus, suggest that MOR activation is a potential mechanism for endogenous opioid modulation of cholinergic activity. To date, anatomical evidence supporting this has not been reported. To delineate the relationship between cholinergic afferents and MOR-containing processes in the dentate gyrus, hippocampal sections were dually immunolabeled for vesicular acetylcholine transporter (VAChT) and MOR-1 and examined by electron microscopy. VAChT immunoreactivity was in unmyelinated axons and axon terminals, and was most often associated with small synaptic vesicles. MOR immunoreactivity was found in axons, axon terminals and, to a lesser extent, perikarya, which resembled GABAergic basket cells. Semi-quantitative ultrastructural analysis revealed that from 5% to 13% (depending on laminar location) of VAChT-immunoreactive (ir) presynaptic profiles contained MOR immunoreactivity. Additionally, 7% of VAChT-ir presynaptic profiles directly apposed MOR-ir axons and terminals, and there were almost no appositions to MOR-ir dendrites. These data suggest that opioids may directly and indirectly modulate acetylcholine release and/or reuptake. In the hilus and molecular layer, 4% of VAChT-ir terminals contacted dendritic shafts that were also contacted by MOR-ir terminals. This suggests that cholinergic afferents and MOR-containing afferents can converge on granule cell dendrites (which are restricted to the molecular layer) and on interneuron dendrites in the hilus. The results of this study provide ultrastructural evidence for direct and indirect modulation of cholinergic systems by μ-opioids in the hippocampal formation.
Backscattering from frost on icy satellites in the outer Solar System

Two extreme models are presented of how frost and ice might be intermixed on a typical satellite surface: areal and intimate mixing. Applying such models to selected representative satellite data, it is found that the frost component of the surfaces of these outer satellites must itself be backscattering, unlike its terrestrial counterpart. The difference may arise because frost particles can have much more complex internal textures under the low-temperature and low-gravity conditions of the outer satellites than is the case on earth.
Internal consistency of a water analysis and uncertainty of the calculated distribution of aqueous species at 25°C

Many water analyses contain more than the minimum number of analytical determinations needed to calculate the distribution of species at ~ 25°C. The speciation of a water that contains n cations and ligands other than H+ and OH− can be calculated if just n analytical determinations are available. In the frequent case where n + 1 (or more) determinations are available, one can calculate from the speciation a value for the (n + 1)th variable. The comparison between this computed value and its analytical counterpart (not used in calculating the speciation) constitutes a test for internal consistency among the n + 1 determinations that make up the whole analysis. Application of this test requires knowing the uncertainties of the calculated speciation and of the value computed for the (n + 1)th variable from the speciation. Such uncertainties have been ignored in previous algorithms, but have been determined herein by a Monte Carlo method of error propagation which is very well suited to systems of nonlinear algebraic equations. By comparing the titration alkalinity against the alkalinity calculated from the speciation, several published analyses for which the cation/anion balance is < 3% can be shown to be internally inconsistent. Such analyses may be unsuitable for geochemical calculations (water/rock interaction, estimation of reservoir temperatures, etc.). Several existing speciation algorithms disregard the possibility that the analytical data used as input are internally inconsistent.
Kinetics measurements of Pb island growth on Si(111)

We present the results of kinetics experiments on quantum-size-effects (QSE) Pb islands formed on Si(111). We have looked at the evolution of seven-layer Pb islands from five-layer Pb islands due to the transport of Pb atoms from the interisland region, overcoming a barrier at the island edges, and moving to the island tops. By analyzing low-energy electron-diffraction and scanning-tunneling microscopy data, we have estimated the barrier for layer formation in this system to be $\ensuremath{\sim}0.32\mathrm{eV}.$ This energy is much larger than that expected from QSE electronic contributions alone.
Time-Lapse Microscopy Reveals Unique Roles for Kinesins during Anaphase in Budding Yeast

The mitotic spindle is a complex and dynamic structure. Genetic analysis in budding yeast has identified two sets of kinesin-like motors, Cin8p and Kip1p, and Kar3p and Kip3p, that have overlapping functions in mitosis. We have studied the role of three of these motors by video microscopy of motor mutants whose microtubules and centromeres were marked with green fluorescent protein. Despite their functional overlap, each motor mutant has a specific defect in mitosis: cin8Δ mutants lack the rapid phase of anaphase B, kip1Δ mutants show defects in the slow phase of anaphase B, and kip3Δ mutants prolong the duration of anaphase to the point at which the spindle becomes longer than the cell. The kip3Δ and kip1Δ mutants affect the duration of anaphase, but cin8Δ does not.
The encouragement of international research co-operation in dentistry

Abstract The speaker discusses suggestions made by scientists from many countries regarding improving international relationships in dental research. Many people believe that periodic international dental research meetings should be held that are of greater scope that those that have been held to date. There appears to be a real hope that existing research organizations could be banded in such a way that each would not lose its identity. Perhaps a single area where improvement is most desired by all is in publication of research findings. The speaker presents the viewpoint of the International Association for Dental Research and asks for discussion from members of other organizations.
Effect of various uncertainties on the performance of occupancy-based optimal control of HVAC zones

Model Predictive Control (MPC) has emerged as a potential control architecture for operating buildings in a more energy efficient manner. We study through simulations the effect of several sources of uncertainty that arise in the implementation of MPC on the energy consumption, thermal comfort, and indoor air quality (IAQ). These include occupancy profile, measurement errors and mismatch between the plant and its model that the control algorithm uses. Simulations are carried out for two extreme cases: a winter day with no solar load and a summer day with high solar load. The study shows that increasing fluctuations in occupancy, errors in measuring occupancy, and model mismatch have the strongest impact on the energy consumption. However, measurement errors in outside temperature and solar load does not have significant impact. Therefore, it is possible to improve the controller performance by using more accurate occupancy sensors. Furthermore, implementation cost can also be reduced by eliminating the sensors and prediction algorithms for predicting outside temperature and thermal loads without compromising the controller performance. Even with these uncertainties, MPC delivers 12–37% reduction of energy use over conventional control methods without affecting thermal comfort and IAQ.
Stability of NaSICON-type Li1.3Al0.3Ti1.7P3O12 in aqueous solutions

Abstract The chemical and electrochemical stability of high-purity lithium aluminum titanium phosphate (LATP) as a solid state electrolyte and physical separator in aqueous electrochemical cells was evaluated using LiOH, LiCl, LiNO3, and LiCOOCH3 salts as the Li source. LATP, with formula Li1.3Al0.3Ti1.7P3O12, was found to be most stable between pH 8–9, with the longest cell operating continuously at 25 mA cm−2 for 625 h at 40 °C in LiCOOCH3. Biaxial strength was 191 ± 11 MPa when tested in mineral oil, 144 ± 13 MPa as measured in air, and 26 ± 7 MPa after exposure to deionized water, suggesting that LATP undergoes stress-corrosion cracking. After exposure to LiOH, the strength was 76 ± 19 MPa. The decrease in strength was observed despite there being no measurable change in a.c. impedance spectra, x-ray diffraction, or sample mass, suggesting phosphate glasses at grain boundaries. At pH values outside of the 7–10 range, eventual membrane degradation was observed in all aqueous systems under electrochemical conditions. While LATP was surprisingly resistant to static corrosion in a hot, aqueous LiOH solution, electrochemical degradation was observed at the cathode due to subsurface pitting. Strength measurements were more instructive than impedance measurements in detecting this degradation.