cssi/SciSciGPT-SciSciNet huggingface dataset:
Detection of Pinholes in Ultrathin Films by Magnetic Coupling

Abstract : When two magnetic films are separated by a nonmagnetic film, pinholes in the nonmagnetic film can allow direct contact and, thereby, direct magnetic exchange coupling between the two magnetic films. We have studied this coupling by having one of the magnetic films pinned and leaving the other free to switch at low field. The pinning is accomplished with test structures based on exchange bias and synthetic antiferromagnetic layers. Since the pinning strength increases sharply at low temperatures but orange-peel coupling does not, low-temperature (77 K) measurements appear to identify whether an observed coupling arises primarily from magnetic coupling through pinholes or primarily from orange-peel roughness. Our measurements appear to indicate that the observed coupling arises primarily from magnetic coupling through pinholes for Cu films less than 2.1 nm thick and for Al2O3 films less than 0.6 nm thick but primarily from roughness-induced (orange-peel) magnetostatic coupling for larger thicknesses.
Sources of pathology underlying listening disorders in children

Some children referred to audiology and developmental disability services have listening difficulties, despite normal audiograms. These children may be tested for 'auditory processing disorder' (APD), a controversial construct suggesting that neural dysfunction in the central auditory system leads to impaired auditory perception. An important question, not currently tested in clinical evaluation, is whether listening difficulties result from problems with bottom-up auditory sensory processing or top-down modulating cognition. Perceptual variability and poor performance on standardized tests suggest that listening difficulties are primarily cognitive in origin. However, evidence for impaired olivocochlear function and temporal processing deficits may implicate peripheral or central auditory dysfunction in some cases. Wide-spread, top-down modulation of auditory cortical, brainstem and ear function suggests that afferent and efferent control systems may not be simple to segregate. During normal maturation, hearing appears to develop in proportion to the complexity of both stimuli and tasks. But some younger individuals have mature hearing, highlighting individual differences that suggest APD may be due to a generalized developmental delay. Recent studies have investigated specific hypotheses showing, for example, that spatial hearing and executive function are compromised in some children with listening difficulties. Using speech stimuli (e.g. consonant-vowel syllables) to examine auditory brainstem responses, and psychophysiological relations between dichotic hearing and cortical physiology, various effects of auditory experience and development point the way to promising approaches for further studies of APD. Newer technology, from genetic sequencing to MRI, may have the sensitivity to test whether and how frequently APD is associated with impaired processing in the auditory system.
Construction of recombinant Nitrosomonas europaea expressing green fluorescent protein in response to co-oxidation of chloroform

Transcriptional fusions with gfp driven by the promoter region of mbla (NE2571) in pPRO/mbla4 and clpB (NE2402) in pPRO/clpb7 were used to transform the ammonia-oxidizing bacterium Nitrosomonas europaea (ATCC 19718). The two genes were chosen because their transcript levels were found at much higher levels in N. europaea in response to oxidation of chloroform and chloromethane. In N. europaea transformed with pPRO/mbla4, green fluorescent protein (GFP)-dependent fluorescence increased from 3- to 18-fold above control levels in response to increasing chloroform concentrations (7 to 28 microM), and from 8- to 10-fold in response to increasing hydrogen peroxide concentrations (2.5-7.5 mM). The GFP-dependent fluorescence of N. europaea transformed with pPRO/clpb7 also showed an increase of 6- to 10-fold in response to chloroform (28-100 microM) but did not respond to H(2)O(2). Our data provide proof of concept that biosensors can be fabricated in ammonia-oxidizing bacteria using "sentinel" genes that up-regulate in response to stress caused either by co-oxidation of chlorinated solvents or by the presence of H(2)O(2). The fabricated biosensors had a consistent concentration-dependent response to chloroform; however, these did not respond to other chlorinated compounds that cause similar cellular stress.
Factor Analysis in Counseling Research and Practice

This article summarizes the general uses and major characteristics of factor analysis, particularly as they may apply to counseling research and practice. Exploratory factor analysis (EFA) and confirmatory factor analysis (CFA) are overviewed, including their principal aims, procedures, and interpretations. The basic steps of each type of factor analysis are elucidated. For EFA, the methods of factor extraction (principal component analysis and principal axis factoring), retention, rotation, and naming are summarized. CFA’s basic operations (model specification, testing, and interpretation) are discussed. In conclusion, EFA and CFA are directly applied to the development of a counseling-related instrument.
Advances in Structured Nonlinear Semiconductor Crystals

Microstructured semiconductors, like orientation-patterned GaAs, achieve quasi-phasematching through controlled, periodic inversions of the crystallographic orientation. These nonlinear optical materials are becoming more mature and are being used to generate mid-infrared and THz radiation.
Shock determination of the Grüneisen parameter for lanthanum and the 6s - 5d transition

Shock-wave overtake measurements have been used to determine sound velocities in lanthanum metal from 0.73 to 2.3 Mbar along the Hugoniot curve. Since these pressures lie in the liquid region, the results can be used to obtain the corresponding pressure and volume dependences of the adiabatic bulk modulus, ${B}_{S}$, and of the Gr\"uneisen parameter, \ensuremath{\gamma}. A calculation by McMahan, Skriver, and Johansson [Phys. Rev. B 23, 5016 (1981)] of the volume and temperature dependence of the 6s-5d transition in lanthanum predicts that \ensuremath{\gamma} should be anomalously large and have a maximum value in the present pressure range. Our results are in qualitative agreement with this prediction, with \ensuremath{\gamma} decreasing with increasing pressure from a maximum value of 1.30 (twice the P=0 value) at V/${V}_{0}$=0.55 (0.73 Mbar, our lowest pressure) to 0.62 at V/${V}_{0}$=0.443 (2.32 Mbar). Technical problems prevented the actual observation of a maximum in \ensuremath{\gamma} at lower pressures.
Placental transfer and fetal deposition of hexachlorobenzene in the hamster and guinea pig

Abstract Hexachlorobenzene (HCB) was administered at dose levels of 0, 1.0, 10.0, or 50.0 mg HCB/kg body wt by gavage to pregnant hamsters and guinea pigs for 6 days up to the time of liver development in the fetus. Samples of maternal fat, thymus, skin, liver, lung, brain, spleen, urinary bladder, muscle, plasma, and blood were analyzed for HCB concentration. Additionally, fetuses, placentas, and yolk sacs were analyzed for HCB content. HCB was found in all tissues assayed. The highest concentrations of HCB were found in the hamster tissues, with the hamster fetuses having a fivefold greater concentration of HCB than the guinea pig fetuses. Comparisons were made of the hamster and guinea pig data with similar data in the mouse and rat.
Casein Kinase 2 Is Activated and Essential for Wnt/β-Catenin Signaling

Wnt/β-catenin signaling is essential to early development. Activation of Frizzled-1 by Wnts induces nuclear accumulation of β-catenin and activation of Lef/Tcf-dependent gene expression. Casein kinase 2 has been shown to affect Wnt/β-catenin signaling. How casein kinase 2 exerts an influence in Wnt signaling is not clear; casein kinase 2 has been reported to be constitutively active (i.e. not regulated). Herein we show to the contrary that casein kinase 2 activity is rapidly and transiently increased in response to Wnt3a stimulation and is essential for Wnt/β-catenin signaling. Chemical inhibition of casein kinase 2 or suppression of its expression blocks Frizzled-1 activation of Lef/Tcf-sensitive gene expression. Treatment with pertussis toxin or knock down of Gαq or Gαo blocks Wnt stimulation of casein kinase 2 activation, as does suppression of the phosphoprotein Dishevelled, demonstrating that casein kinase 2 is downstream of heterotrimeric G proteins and Dishevelled. Expression of a constitutively active mutant of either Gαq or Gαo stimulates casein kinase 2 activation and Lef/Tcf-sensitive gene expression. Thus, casein kinase 2 is shown to be regulated by Wnt3a and essential to stimulation of the Frizzled-1/β-catenin/Lef-Tcf pathway.
Abstract A42: Doses of selective estrogen receptor modulations (SERMS) required for prevention and therapy of chemically induced mammary cancers

Selective estrogen receptor modulators (SERMs) interfere with the activation of the estrogen receptor. SERMs have been shown to be effective for both treatment and prevention of breast cancer. Here we examine the ability of tamoxifen and arzoxifene, a more easily absorbed form of raloxifene, to prevent mammary tumors at a significantly lower dosage than those used for treatment. For prevention studies, female Sprague-Dawley rats (50 days of age) were injected with a single i.v. dose of MNU resulting in the development of multiple ER-positive mammary tumors beginning 7 weeks after carcinogen treatment. Rats were administered the preventive agent beginning five days after carcinogen administration. When the agents were tested at does varying between 0.15-3.3 ppm in the diet, both agents caused a dose dependent increase in preventive activity. The highest doses of tamoxifen (3.3 ppm) and arzoxifene (3.0 ppm) both decreased tumor multiplicity greater than 90%. Both of these doses are less than one-fifth the human equivalent dose (HED) based on standard FDA scaling factors. Both doses also resulted in substantial decreases in mammary gland development. These dosages were then used in a therapy setting to compare the efficacy. For these studies, MNU treated rats were allowed to develop their first palpable mammary tumor (70-150 mm2) before initiating treatment. Tumor growth or regression was followed by caliper measurements. Neither of the preventive doses of these SERMs exhibited therapeutic activity although substantially higher doses of tamoxifen (33 or 100 ppm) were relatively effective. These results are in contrast to our prior findings with other classes of agents (RXR agonists, EGFR inhibitors, and aromatase inhibitors) in which highly effective preventive doses were as effective as therapeutic doses in this model. These results demonstrate the unique dose differential regarding prevention and therapy with SERMs. Microarray analysis of tumors treated for 5 days with tamoxifen at doses of 3.3ppm or 100ppm reveals overlapping significant gene changes of similar magnitude in comparison to control treated tumors although there were significant gene changes seen at the therapeutic dose which were not observed at the lower dose. These studies raise two questions: 1) whether this class of agents might be used at significantly lower doses in a pure prevention setting as contrasted with a therapeutic setting where they were initially defined; 2) are there gene expression changes which might be used to help identify this differential dosing for prevention vs. therapy. Citation Information: Cancer Prev Res 2010;3(12 Suppl):A42.
Fast optimization and planning of clinical interstitial ultrasound hyperthermia using superposition and surrogate models of temperature distributions

Conformable hyperthermia can be administered in the prostate, immediately following radiation, using multiple (2-6) directional ultrasound transducer arrays through previously implanted HDR brachytherapy catheters. These ultrasound devices provided controlled heating in angle and length. To plan a hyperthermia treatment, the patient anatomy and catheter geometry were reconstructed from CT images. Transducer powers were estimated to maximize the heated tumor volume, while sparing the surrounding organs. Fast computation of temperature elevations was performed by approximating the temperature rise induced at a point as the superposition of temperature increases resulting from individual transducers. Steady state temperature increases due to individual transducer elements (90 - 360° sector angles, 0 - 2 W) were precalculated and stored in a lookup table. Instead of using computationally expensive 3D finite element methods (FEM), temperature profiles were generated through interpolation and superposition of the precomputed data. These approximate models were included in a gradient search optimization, reducing the treatment planning time by a factor greater than 4.0 compared to the FE model. For 10 patient cases with dominant intraprostatic lesions, the optimized treatment plans were furnished in 10 - 35 minutes and yielded T 90 > 40.0°C in most cases. The corresponding T 90 values obtained through rigorous FE modeling were within 0.5 °C.
Adenovirus-mediated overexpression of microsomal triglyceride transfer protein (MTP): mechanistic studies on the role of MTP in apolipoprotein B-100 biogenesis, by

The intracellular concentration of the microsomal triglyceride transfer protein large subunit (lMTP), the abetalipoproteinemia gene product, is tightly controlled. To date, attempts at overexpressing lMTP in vivo or in vitro have been unsuccessful. We successfully overexpressed lMTP in HepG2 cells using an adenoviral vector containing an lMTP cDNA, AdMTP. AdMTP-transduced HepG2 cells overexpressed MTP activity. They secreted increased amounts of apoB-100 lipoproteins with LDL and HDL density into the medium. lMTP overexpression alone minimally changed the density profile of apoB-containing lipoproteins, but addition of oleic acid shifted the profile toward lower densities. Oleic acid had a greater stimulatory effect on apoB-100 secretion in control HepG2 cells than in AdMTP-transduced cells, because (i) adenoviral transduction per se suppressed protein synthesis, affecting apoB-100 and albumin equally, and (ii) adenoviral transduction partially attenuated the increase in triglyceride synthesis in response...
Analysis of non‐Hodgkin's lymphomas with nodular and favorable histologies, stages I and II

Between 1961 and 1980, 124 patients with Stages I and II nodular lymphocytic poorly differentiated (NLPD), nodular mixed histiocytic-lymphocytic (NM), nodular histiocytic (NH), or diffuse well-differentiated lymphocytic (DLWD) lymphoma according to the Rappaport classification were treated at Stanford University. Initial staging studies included lymphangiography in 91%, bone marrow biopsy in 93%, and diagnostic or staging laparotomy in 41% of patients. All patients were treated with megavoltage irradiation to either involved field (IF), extended field (EF), or total lymphoid fields (TLI) to a total dose of 3500-5000 rad. Median follow-up was 5.5 years. Kaplan-Meier actuarial survival at 5, 10, and 15 years was 84%, 68%, and 42%, respectively. Freedom from relapse at 5 and 10 years was 62% and 54%, respectively. In addition, there was a flattening of the relapse curve suggesting cure of approximately 50% of patients. Patients with NH had a significantly poorer survival (P = 0.03) while there were no differences among the other histologic groups. Freedom from relapse was higher in patients treated with TLI compared with those treated with IF or EF. However, a prospective study of 20 patients who all underwent staging laparotomy and were randomized to treatment with either IF or TLI revealed no significant difference in either survival or freedom from relapse. Utilizing multivariate analysis for the entire group, important prognostic factors included age, stage, histologic subtype, and treatment field.
Atypical Forms of M. tuberculosis

SUMMARY Atypical forms of M. tuberculosis have been discussed from the earliest identification of variations to the present time, and instead of being a mystery, it is all within the laws of biology. While there may be phenomena not yet clearly understood in the life of bacteria, the mutation theory of DeVries seems to be adequate to explain most of the changes that have appeared and are continuing to appear as they do in other forms of life. Even before the recent work, the mutation theory was plausible; where changes could be demonstrated by stimulants, such as the x-ray and chemicals on certain species of life. The biochemical and x-ray identification of the structure of giant molecules in the chromosomes are more revealing and convincing. Sometimes major displacements occur within the molecule so that the new molecule is sufficiently different to result in variation of the progeny. These changes are a continuing process throughout life on the earth and help explain the presence of the widespread of life. When there has been a radical change in the environment, a mutant may result and will grow when all the other forms, including the parent strains, are suppressed or are over-grown. Use of antimicrobial drugs has brought the phenomenon into clear perspective. The drugs have blocked the formation of new molecules leaving the mutants free to overgrow the parents as resistant forms. The question whether drugs cause mutation is still unanswered, but the wiping out of the sensitive parent forms no doubt leaves a greater number of atypical bacilli. Attempts are being made to classify the various atypical forms. Many of them still retain varying degrees of virulence for the human host and thereby create problems.
On the decentralized control of interconnected systems

Abstract Recently, it was shown [1] how to reduce the order of the decentralized control problem for interconnected systems by using local dynamic feedback. The analysis was carried out with polynomial matrices. In this letter, these results are reproduced in state space using the Generalized Hessenberg Representation (GHR). This analysis shows how the interaction between the interconnection structure and the local system structure generates the result above. In addition, this analysis leads directly to numerical algorithms.
Adjustment of wind fields for application in air pollution modeling

Abstract A technique to construct an accurately specified wind field, which can be used as input to air pollution and meteorological models, is developed based on variational calculus principles, and extends prior studies using this approach. Two-dimensional wind data sets over the region are constructed using a1/r2 interpolation procedure. These sets of wind data are subject to two constraints, satisfaction of the continuity equation and observed vorticity, so that the resultant adjusted wind field retains the flow characteristics of the observed data and is mass conservative. The direct-differencing technique is used to compute the vertical wind field from the adjusted horizontal field. Cases of constant and variable atmospheric density are considered. The divergence of the adjusted wind field is found to be considerably reduced, and the vertical component of vorticity of the observed wind field is preserved by the adjusted field. The vertical wind fields obtained are representative of ‘well-behaved’ wind fields with minimal abnormalities in magnitude and distribution.
Pharmacodynamics of alpha2-adrenoceptor agonists

Abstract Two α 2 -agonists are currently available for peri-operative use—clonidine and dexmedetomidine. These α 2 -agonists have sympatholytic, analgesic, sedative and anxiolytic properties, resulting in diverse pharmacodynamic effects that make them useful as peri-operative anaesthetic adjuncts. Their main cardiovascular effects are a decrease in blood pressure and heart rate. Peri-operatively they reduce the amount of hypertension and tachycardia, thus improving haemodynamic stability. Their sedative effects are dose dependent, and with appropriate doses, patients remain rousable. The combination of the haemodynamic and sedative effects makes α 2 -agonists especially suitable for post-operative or ICU patients with increased sympathetic nervous system tone. Some of the other clinical effects of these drugs are anxiolysis, a reduction of anaesthetic and opioid requirements, analgesia and the prevention of shivering. They have a minimal effect on respiration. The side-effects include bradycardia and hypotension.
Blind channel estimation based robust physical layer key generation in MIMO networks

An emerging area of interest in wireless security is the generation of secret encryption keys by leveraging the features of the physical propagation channel. The shared randomness of the wireless channel between two legitimate nodes in a communication network is exploited to provide strong secrecy. The secret keys are generated based on fluctuations or evolution of the wireless channel state. However, to the best of our knowledge, little work has been performed on algorithms to exploit the increased randomness available to wireless nodes equipped with MIMO antennas. In this paper, we present a practical key generation scheme for MIMO channels based on quantization performed on blind channel estimates. Our schemes generate random keys for transmitter and receiver by simultaneously quantizing the blind channel estimates. Our schemes are simulated for a realistic fading channel model, and performance metrics for error rate and efficiency are provided.
Neonatal reversible focal cerebral ischemia: a new model

While numerous animal models exist for studying neonatal brain injury after cerebral ischemia-hypoxia, an adequate model for assessing reversible focal ischemia in the neonatal rat has not been reported. This paper describes in detail a new surgical procedure for creating a non-hemorrhagic, reperfused focal ischemic lesion in the neonatal, 7-day-old rat pup.
Descriptive epidemiology of body weight and weight change in U.S. adults.

Data on body weight and weight change collected from nationally representative samples of U.S. adults are reviewed. The body mass index (weight [kg]/height [m2]) has a low correlation with height and is used to compare body weights between persons of differing heights. The BMI varies to a greater degree in women than in men. Below the 75th percentile of the BMI distribution, women have lower BMIs than men, whereas at the 75th percentile and above, women have higher BMIs than men. Overweight is defined as a BMI of 27.8 or more in men and of 27.3 or more in women, corresponding to approximately 20% or more above desirable weight in the 1983 Metropolitan Life Insurance Company tables. For persons of average height (men, 5'9"; women, 5'4") this definition is equivalent to a body weight above 85 kg (187 pounds) in men and above 72 kg (158 pounds) in women. Among adults 20 to 74 years of age, 24% of men and 27% of women are overweight, yielding an estimated total of 34 million persons in the United States. The prevalence of overweight increases with age, for both men and women but to a greater degree in women. Blacks and Hispanics have a higher prevalence of overweight than do whites, especially among women. Between 1960 and 1980, the prevalence of overweight among whites increased by 3% in women and by 6% in men. In blacks, however, the prevalence of overweight increased by 7% in women and by 28% in men. Longitudinal body weight measurements taken 10 years apart show that adults younger than 55 years tend to gain weight, whereas those 55 years and older tend to lose weight. The youngest adults gain the most weight, and the oldest adults lose the most weight. In all age groups, women have substantially greater variation in their 10-year weight change than do men.
Localization of fibrinogen during aggregation of avian thrombocytes

The thrombocyte is the avian equivalent of the mammalian blood platelet and is involved in hemostasis through a fibrinogen-mediated process. Although fibrinogen has been implicated as a molecular bridge between activated cells during aggregation, the location of this molecule and its receptor on thrombocytes has not been characterized. Pigeon fibrinogen, isolated from plasma by precipitation with PEG-1000 and purified over Sepharose 4B, was used to study receptor-ligand interaction. Separation of pigeon fibrinogen on SDS-PAGE resulted in three peptides of molecular mass 62, 55, and 47 kDa, which were comparable to those of human fibrinogen. The role of fibrinogen and its receptor in thrombocyte function was established by turbidimetric aggregation using thrombin as an agonist under conditions requiring Ca2+ and fibrinogen. Maximum response occurred using 3 mM Ca2+ and 100 micrograms/ml fibrinogen. Fibrinogen-dependent aggregation was inhibited by an anti-GPIIb antibody, verifying a role for fibrinogen receptors in thrombocyte function. Fibrinogen-gold conjugates were used to describe receptor and ligand localization on aggregated cells. Computer reconstruction was used to verify relocalization of fibrinogen receptors following activation. Fibrinogen distribution changed from a dispersed state in preactivated cells to focal localization at points of cell contact and along pseudopods following activation. This selective positioning of fibrinogen suggests that a functional relocalization of the receptor occurs upon thrombocyte activation, and this relocation facilitates the role of fibrinogen as a molecular bridge. These studies establish similarities between the avian and the human systems and document the conserved nature of the hemostatic process.
Correlation Between Intraocular Pressure and CD4+ T-Lymphocyte Counts in Patients With Human Immunodeficiency Virus With and Without Cytomegalovirus Retinitis

Purpose To determine the intraocular pressure in patients with human immunodeficiency virus (HIV) with and without cytomegalovirus retinitis, and to correlate intraocular pressure with CD4+ T-lymphocyte count and the presence, extent, and activity of cytomegalovirus retinitis. Method Intraocular pressure was measured with calibrated Goldmann applanation tonometers in two groups of patients. Group A included 84 patients with HIV (120 eyes) with cytomegalovirus retinitis, and Group B included 110 patients with HIV (183 eyes) without cytomegalovirus retinitis. Thirty-three patients without HIV (66 eyes) were included as a control group. Step-wise regression analysis of intraocular pressure included correlation with cytomegalovirus retinitis (presence, extent, and activity), CD4+ T-lymphocyte count, age, and gender. Results The mean intraocular pressure was 9.8 mm Hg in Group A, 12.6 mm Hg in Group B, and 16.1 mm Hg in the control group. All three groups were statistically different from each other when intraocular pressure was compared (P Conclusion Intraocular pressure is lower than normal in patients with HIV. Decreased CD4+ T-lymphocyte count is the major association with low intraocular pressure (20% of the effect); extent of cytomegalovirus retinitis accounts for 8% of the effect. Knowledge of the normal range of intraocular pressure in patients with HIV will be important to the understanding and treatment of glaucoma and other disorders or treatments affecting intraocular pressure.
Sharp bounds on the distribution of treatment effects and their statistical inference

In this paper, we propose nonparametric estimators of sharp bounds on the distribution of the treatement eect of a binary treatment and establish their asymptotic distributions. We note the possible failure of the standard bootstrap with the same sample size and apply the fewer-than-n bootstrap to making inferences on these bounds. The …nite sample performances of the con…dence intervals for the bounds based on normal critical values, the standard bootstrap, and the fewer-than-n bootstrap are investigated via a simulation study. Finally we establish sharp bounds on the treatment eect distribution when covariates are available.
Unoccupied orbitals of C and O on Fe(100)

Abstract Inverse photoemission experiments from c(2 × 2) carbon and 1 × 1 oxygen overlayers on Fe(100) reveal adsorbate states at 2.5 and 3.9 eV for C and at 1.7 eV for O. They are assigned to antibonding combinations of C 2p and O 2p states with Fe 3d states. For oxygen on Fe(100) the adsorbate state resonates with the minority spin Fe 3d band, but not with the majority band, in agreement with a recent first principles calculation. Together with previous photoemission results we obtain the energy levels for a complete surface reaction, i.e., dissociation/recombination of CO on Fe(100).
Direct analysis of small‐angle equatorial x‐ray scattering from fibrous systems. II. Methods of extracting physical parameters describing the scattering system

Small-angle equatorial x-ray scattering from fibrous systems is often complicated by the effects of morphological organization and/or heterogeneities as well as by macromolecular structure and organization influencing this same region of scattering space. In previous work it was shown that closed form mathematical expressions could be obtained for the Patterson function, without prior assumptions about the scattering system, when the intensity data were purposely truncated. In this paper the use of these expressions to extract the physical parameters describing the scattering system is demonstrated by application to a model system. The expressions are also expanded to include lattice distortions and long range coherency. A second approach is presented for cases when the coherence is small, and finally the use of higher-resolution data is discussed.
A study of internal damage of metal matrix composites by neutron diffraction

Using neutron diffraction, we have measured the elastic phase strains of Al/TiC and Al/SiC composites under uniaxial tensile loading. The phase strains were used to reconstruct the global elastic strain. It has been found that, above macroscopic yield, the global elastic strain response is not linear. A theoretical model shows that the nonlinearity is dictated by changes in the ratio of longitudinal phase stresses. Furthermore, the changes in this ratio resulting from matrix plasticity and reinforcement fracture are different which leads to distinct slope changes in the global elastic strain response that can be used to distinguish the onset of these two processes on the global elastic strain loading curve.
Force relaxation and thin filament protein phosphorylation during acute myocardial ischemia.

Ischemia impairs myocardial function and may contribute to the progression of heart failure. In this study, rats subjected to acute ischemia demonstrated reduced Ca2+-activated force as well as a decrease in myosin-binding protein-C, titin, and Ser23/24 phosphorylation of troponin I (TnI). All three proteins have been demonstrated to be downstream targets of β-adrenergic receptor activation (β-AR), leading to the hypothesis that decreased β-AR signaling during ischemia leads to reduced protein phosphorylation and reduced rate constants of force relaxation. To test this hypothesis, force relaxation transients were recorded from permeabilized perfused and ischemic rat heart fibers following photolysis of the caged chelator diazo-2. Relaxation transients were best fit by double exponential functions whereby the majority (>70%) of the force decline was described by the fast rate constant, which was ∼5 times faster than the slow rate constant. However, rate constants of relaxation between perfused and ischemic fibers were not different, despite significant decreases in sarcomeric protein phosphorylation in ischemic fibers. Treatment of perfused fibers with a cAMP analog increased Ser23/24 phosphorylation of TnI, yet the rate constants of relaxation remained unchanged. Interestingly, similar treatment of ischemic fibers did not impact TnI phosphorylation or force relaxation transients. Therefore, acute ischemia does not influence the rate constants of relaxation of permeabilized fibers. These results also suggest that the physiological level of sarcomeric protein phosphorylation is unlikely to be the primary driver of relaxation kinetics in permeabilized cardiac muscle fibers. © 2010 Wiley-Liss, Inc.
Heroes, Organizations and High Reliability

Organizational research has shown many cases where organizational ‘heroes’are honoured, and heroic tales are used not only in the process of building organizational reliability and performance, but for clarifying organizational values and culture and transmitting them from one generation to the next. Some high-reliability organizations studied also display these properties; yet, there are some that are actively ‘anti-heroic,’disparaging individual exploits. An inquiry into the role of heroes and heroics in organizations leads to a typology by which hero-avoiding and hero-seeking organizations can be characterized and shows that both types are adaptations to their particular technical and functional environments. A great deal more remains to be learned about the dynamics of organizations seeking and maintaining reliability in very demanding circumstances before we can fully understand how the balance between holistic control and heroics might be chosen.
Aerobic Oxidative Coupling of o-Xylene: Discovery of 2-Fluoropyridine as a Ligand to Support Selective Pd-Catalyzed C-H Functionalization.

An improved method for the direct oxidative coupling of o-xylene could provide streamlined access to an important monomer used in polyimide resins. The use of 2-fluoropyridine as a ligand has been found to enable unprecedented levels of chemo- and regioselectivity in this palladium-catalyzed aerobic oxidative coupling reaction. Preliminary insights have been obtained into the origin of the effectiveness of 2-fluoropyridine as a ligand.
Structure of the Tomato Glycoalkaloid Tomatidenol-3-β-lycotetraose (Dehydrotomatine)

Experiments were carried out to establish the structure of the monosaccharides comprising the carbohydrate side chain of the tomato glycoalkaloid dehydrotomatine. This was accomplished by (a) isolating dehydrotomatine and α-tomatine from commercial tomatine, (b) derivatizing the monosaccharides formed on acid hydrolysis of commercial tomatine, dehydrotomatine, and α-tomatine to alditol acetates and methylated alditol acetates, and (c) determining the structures of the galactose, glucose, and xylose derivatives by gas chromatography−mass spectrometry. Both dehydrotomatine and α-tomatine have the same tetrasaccharide side chain. They differ only by the presence in dehydrotomatine of a double bond at carbon atoms 5 and 6 of ring B and its absence in α-tomatine. Dehydrotomatine, or tomatidenol-3β-lycotetraose, appears to represent a new class of glycoalkaloids in which a lycotetraose carbohydrate side chain is attached to an aglycon containing a double bond. Biosynthetic pathways leading to the formation of d...
Magellanic Cloud Structure from Near-Infrared Surveys. II. Star Count Maps and the Intrinsic Elongation of the Large Magellanic Cloud

I construct a near-IR star count map of the LMC and demonstrate, using the viewing angles derived in Paper I, that the LMC is intrinsically elongated. I argue that this is due to the tidal force from the Milky Way. The near-IR data from the Two Micron All Sky Survey (2MASS) and the Deep NearInfrared Southern Sky Survey (DENIS) are ideally suited for studies of LMC structure because of the large statistics and insensitivity to dust absorption. The survey data are used to create a star count map of red giant branch and asymptotic giant branch stars. The resulting LMC image shows the well-known bar but is otherwise quite smooth. Ellipse —tting is used for quantitative analysis. The radial number density pro—le is approximately exponential, with a scale length kpc. However, there is an r d B 1.3¨1.5 excess density at large radii that may be due to the tidal eUect of the Milky Way. The position angle and ellipticity pro—le both show large radial variations but converge to and P.A. maj \ 189i.3^ 1i.4 v \ 0.199 ^ 0.008 for At large radii, the image is in—uenced by viewing perspective (i.e., one side r Z 5i. of the inclined LMC plane being closer to us than the other). This causes a drift of the center of the star count contours toward the near side of the plane. The observed drift is consistent with the position angle of the list of nodes inferred in Paper I. The fact that # diUers from indicates # \ 122i.5^ 8i.3 P.A. maj that the LMC disk is not circular. Deprojection shows that the LMC has an intrinsic ellipticity v@@ \ 0.31 in its outer parts, considerably larger than typical for disk galaxies. The outer contours have a more or less common center, which lies D0.4 kpc from the center of the bar. Neither agrees with the kinematic center of the H I gas disk. The LMC is elongated in the general direction of the Galactic center and is elongated perpendicular to the Magellanic Stream and the velocity vector of the LMC center of mass. This suggests that the elongation of the LMC has been induced by the tidal force of the Milky Way. The position angle of the line of nodes diUers from the position angle of the line of maximum line-of# max sight velocity gradient. Results from H I gas and discrete tracers indicate that # max [ # \ 20i¨60i. This could be due to one or more of the following: (1) streaming along noncircular orbits in the elongated disk; (2) uncertainties in the transverse motion of the LMC center of mass, which can translate into a spurious solid-body rotation component in the observed velocity —eld; or (3) an additional solidbody rotation component in the observed velocity —eld due to precession and nutation of the LMC disk as it orbits the Milky Way, which is expected on theoretical grounds.
Effect of high-frequency peripheral nerve and dorsal column stimulation on neuronal responses in feline nucleus reticularis gigantocellularis after nociceptive electrical stimulation

Abstract High-frequency peripheral nerve and dorsal column stimulation have been used clinically to alleviate chronic pain in human patients. However, the mechanisms underlying the analgesic effect of these procedures have not yet been clearly elucidated. The purpose of this investigation was to study the effect of high-frequency dorsal column and peripheral nerve stimulation on neuronal responses in feline nucleus reticularis gigantocellularis after nociceptive stimulation. Whereas dorsal column stimulation had little effect on neuronal responses, high-frequency stimulation of one branch of a divided peripheral nerve typically abolished neuronal responses to stimulation of the other branch of the divided nerve. Similarly, high-frequency stimulation of a contralateral canine tooth pulp abolished the neuronal responses to test stimulation of the ipsilatral canine tooth pulp. Of special significance was the finding that high-frequency stimulation interfered with sensory transmission for periods up to at least 6 hours in duration. These findings have implications for the clinical control of intractable pain and for the role of small-diameter afferents.
Clearwater Russet: A Dual-Purpose Potato Cultivar with Cold Sweetening Resistance, High Protein Content, and Low Incidence of External Defects and Sugar Ends

Clearwater Russet is a medium-late maturing, russet-skinned, potato cultivar suitable for processing or fresh pack. It is notable for having a low incidence of external defects that contributes to its high U.S. No 1 yield relative to the dual-purpose industry standard, Russet Burbank. Clearwater Russet also maintains low glucose concentrations in its tubers during long-term storage making it an exceptional processing variety. With its low incidence of sugar ends and cold-induced sweetening resistance, Clearwater Russet can be stored at a temperature of 7.2°C for up to 250 days without the need for reconditioning; fry color from this storage regime is consistently ≤1.0 (USDA Fry Color Scale). This cultivar is also notable for its high tuber protein content, which was 33% greater than that of Russet Burbank. In full-season trials conducted over a 3-year period in California, Colorado, Idaho, Oregon, and Washington, Clearwater Russet had total yields slightly lower than Ranger Russet and Russet Burbank, but averaged 1% and 33% higher U.S. No. 1 yields, respectively, across all states. Average specific gravity of Clearwater Russet is comparable to Ranger Russet and significantly higher than Russet Burbank. Clearwater Russet is resistant to potato virus X (PVX) and tuber late blight and is moderately resistant to Verticillium wilt, common scab, and the common strain of potato virus Y (PVYO). Symptoms of infection with two necrotic strains of PVY were not observed in tubers of Clearwater Russet or Russet Burbank, but were observed in Ranger Russet. Blackspot bruise reaction for Clearwater Russet is less pronounced than for either Ranger Russet or Russet Burbank. The incidence of hollow heart in Clearwater Russet is intermediate between Ranger Russet and Russet Burbank. Internal brown spot has been noted as a problem for Clearwater Russet in the Columbia Basin of Oregon, but has not been observed as problematic in other growing regions. Clearwater Russet was released in 2008 by the USDA-ARS and the Agricultural Experiment Stations of Idaho, Oregon, and Washington, and is a product of the Pacific Northwest Potato Variety (Tri-State) Development Program.
Where am I? Locating Myself and its Implications for Collaborative Research

This paper examines how a younger white female graduate student and an African American female undergraduate viewed the relationship between the graduate student and older African American working class women. This relationship was formed around a community garden project. The graduate student understood the relationship to be based on gender and class background similarities; the undergraduate viewed it based on race differences and unexamined white privilege. Both interpretations are challenged as unidimensional. Through this re-telling, questions are raised about why situating ourselves via our identities is not practiced more frequently. Possible explanations of this lack of attention to situativity include a Cartesian philosophy of science that separates objectivity and subjectivity, a general unawareness of privilege by those who have it, and a dominant scientific discourse that neglects the role of the researcher. This paper illustrates why reflexivity is crucial for the work of community psychology.
Purification and cloning of a mouse ribosomal gene fragment in coliphage lambda

Abstract We have formed and characterized a recombinant between the EK2 vector AgtWES·λC and a portion of the mouse ribosomal genes. A 6.6 kb end oR·Eco RI fragment was purified from total mouse DNA using RPC-5 ion exchange chromatography and then cloned and detected twice among 183 hybrid phage screened. In situ hybridization of restriction fragments of the hybrid phage DNA revealed that the inserted fragment contained both 18S and 28S RNA sequences. Electron microscopic analysis further suggested that most, if not all, of the 28S RNA sequence was present in the insert. The orientation of the 28S sequences in the hybrid phage was such that the “sense” of the inserted fragment should be under the control of the leftward promoter of λ.
Wide field x-ray surveys: wide field x-ray telescope (WFXT) and notional wide field imager (N-WFI)

ABSTRACT Wide eld X-ray surveys require large eld of view telescopes operating in a step and repeat orslow scanning mode in order to cover large areas of the sky e ciently. Here we discuss two similar,yet dierent designs for a wide eld survey mission that can each be accomplished for a cost ofless than  $1B (FY 2012) and that cover many hundreds to several thousand deg 2 , with mediumdepth  few10 16 ergs 1 cm 2 , and several 10's of degrees with very long exposure time to adepth approaching  3 10 17 ergs 1 cm 2 . We review the WFXT design and compare it with theNotional Wide Field Imager (N-WFI) concept that was developed by the NASA CST in responseto a charge from NASA to de ne generic (or notional) missions that can accomplish some (or all)of the IXO science, but at a reduced cost. 1. INTRODUCTION It has been about 20 years since the all sky X-ray survey by the ROSAT PSPC (RASS 1 ) was done.The eROSITA instrument, part of the Spectrum X-Gamma mission by Russia and Germany (
Similarities and differences in depression among black and white nursing home residents

The authors examined racial similarities and differences in depressive symptomatology, diagnosis, and the predictors of depression in four independent nursing homes, conducting analyses across all sites and separately for the nursing home with the greatest racial balance (NH4). All-site data indicated that white residents showed more depression than black residents. There were no racial differences in the depression diagnosis derived from a structured interview of DSM-III-R. At NH4, there were no statistically significant racial differences in any of the measures of depression. Across sites, functional disability was the strongest predictor of both Geriatric Depression Scale (GDS) and DSM-III-R diagnosis of depression in both blacks and whites. Cognitive impairment and use of antidepressants were predictive of medical chart diagnosis of depression across sites, but not of depression measured by GDS or DSM-III-R criteria. At NH4, functional disability was predictive of GDS depression, but only among whites. Age was not an important predictor of depression. Results indicate the importance of considering the method used to diagnose depression and the necessity of controlling for the nursing home setting when examining racial differences in depression.
The Effect of Diphenols and Bisphenols on Growth and Control of Cecal Coccidiosis in Broilers

Abstract IN RECENT years numerous reports have shown the successful use of various sulfonamides in the prevention and control of cecal coccidiosis caused by Eimeria tenella in chickens. Barber (1948) and Grumbles, Delaplane, and Higgins (1948) have cited reports covering this subject. Recently it came to our attention that another group of compounds classified generally as diphenols and bisphenols possessed significant activity against the cecal type of coccidiosis infection in chickens. Furthermore, it appeared that protection could be afforded through continuous medication at relatively low expense. In addition to their favorable action against coccidiosis infection it appeared that some of the bisphenols might possess some estrogen-like activity. A comprehensive review by Solmssen (1945) on synthetic estrogens lists a number of diphenols having estrogenic activity in rats. The most potent of these, however, were approximately only one one-thousandth times as active as stilbestrol. It seemed desirable to subject these compounds to further . . .
A metabolic and body-size scaling framework for parasite within-host abundance, biomass, and energy flux.

Abstract Energetics may provide a useful currency for studying the ecology of parasite assemblages within individual hosts. Parasite assemblages may also provide powerful models to study general principles of ecological energetics. Yet there has been little ecological research on parasite-host energetics, probably due to methodological difficulties. However, the scaling relationships of individual metabolic rate with body or cell size and temperature may permit us to tackle the energetics of parasite assemblages in hosts. This article offers the foundations and initial testing of a metabolic theory of ecology (MTE) framework for parasites in hosts. I first provide equations to estimate energetic flux through observed parasite assemblages. I then develop metabolic scaling theory for parasite abundance, energetics, and biomass in individual hosts. In contrast to previous efforts, the theory factors in both host and parasite metabolic scaling, how parasites use host space, and whether energy or space dictate...