cssi/SciSciGPT-SciSciNet huggingface dataset:
Mechanistic role of each metal ion in Streptomyces dinuclear aminopeptidase: Peptide hydrolysis and 7 × 1010-fold rate enhancement of phosphodiester hydrolysis

Abstract The dinuclear aminopeptidase from Streptomyces griseus ( Sg AP) and its metal derivatives catalyze the hydrolysis of the phosphoester bis( p -nitrophenyl) phosphate (BNPP) and the phosphonate ester p -nitrophenyl phenylphosphonate with extraordinary rate enhancements at pH 7.0 and 25 °C [A. Ercan, H. I. Park, L.-J. Ming, Biochemistry 45, (2006) 13779–13793.], reaching 6.7 billion-fold in terms of the first-order rate constant of the di-Co(II) derivative with respect to the autohydrolytic rates. Since phosphoesters are transition state-like inhibitors in peptide hydrolysis, their hydrolysis by Sg AP is quite novel. Herein, we report the investigation of this proficient alternative catalysis of Sg AP and the role of each metal ion in the dinuclear site toward peptide and BNPP hydrolysis. Mn(II) selectively binds to one of the dinuclear metal sites (M1), affording MnE- Sg AP with an empty ( E ) second site for the binding of another metal (M2), including Mn(II), Co(II), Ni(II), Zn(II), and Cd(II). Peptide hydrolysis is controlled by M2, wherein the k cat values for the derivatives MnM2- Sg AP are different yet similar between MnCo- and CoCo- Sg AP and pairs of other metal derivatives. On the other hand, BNPP hydrolysis is affected by metals in both sites. Thus, the two hydrolytic catalyses must follow different mechanisms. Based on crystal structures, docking, and the results presented herein, the M1 site is close to the hydrophobic specific site and the M2 site is next to Tyr246 that is H-bonded to a coordinated nucleophilic water molecule in peptide hydrolysis; whereas a coordinated water molecule on M1 becomes available as the nucleophile in phosphodiester hydrolysis.
An Operational Experiment in the Statistical-Dynamical Prediction of Tropical Cyclone Motion

Abstract Current statistical models for the prediction of tropical cyclone motion use predictors derived from climatology, persistence, and observed geopotential height data. This paper describes an operational experiment conducted during the 1973 and 1974 Atlantic hurricane seasons whereby prognostic 500 mb height data from the National Meteorological Center's primitive equation model were also included as statistical predictors. Both the “perfect-prog” and a “simulated-model-output-statistics” (SMOS) approach were utilized to introduce the prognostic height data into the statistical prediction equations. Compared to the current “state-of-the-art” of tropical cyclone forecasting, the perfect-prog technique gave relatively poor displacement forecasts for the first half of the 72 h forecast period but excellent forecasts for the latter half. The SMOS method performed well over the entire period but the 72.h displacement error was somewhat greater than that of the perfect-prog equations. The results of the ...
Comparison of two indices of diet quality with acculturation factors and demographics in Haitian Americans.

This study examined associations of language preference and length of stay in the United States and diet among 132 Haitian Americans aged ≥35, born in Haiti. Two dietary indices, Healthy Eating Index (HEI) and Alternative Healthy Eating Index (AHEI), were used to assess dietary quality. Years in the United States (>15 years; B = 0.063, p = .012) and female gender (B = 5.63, p = .028) were positively associated with AHEI. Lower HEI scores were associated with speaking no English (B = −6.11, p = .026). Participants reporting an income under 20,000/yr had lower AHEI scores (B = −7.63, p = .014). Concurrent use of these indices would provide a screening tool for nutrition intervention. Public health programs targeting low-cost resources, such as community gardening, are recommended to reduce health disparities among this population.
Concentration-dependence of aniline-induced methemoglobinemia in dogs: A derivation of an acute reference concentration

Four male Beagle dogs per group were head-only exposed to aniline vapor in concentrations ranging from 15.8 to 493.6 mg/m3. Each exposure session was for 4h. Additionally, one group of dogs was both head-only and whole-body exposed to approximately 241 mg/m3 to better appreciate the contribution of dermal uptake on methemoglobin (MetHb) induction. The exposure paradigm chosen was comparable to a dose-escalation type of study, however, providing adequate recovery periods between each exposure session to exclude 'carry-over' effects from one exposure session to another. This was verified by the determination of standard hematology endpoints before and after each exposure session. The time- and concentration-dependence of MetHb was analyzed as the key endpoint. The results of this study show that MetHb was maximal around the end of the 4 h exposure period. Significantly increased MetHb was observed at concentrations equal and above 30.3 mg/m3 at a duration of exposure of at least 60 min. The extent of MetHb formation observed in some hyperventilating dogs suggests that the dosing-rate is important for the outcome of test. Whole body exposed dogs displayed markedly higher MetHb values when compared to head-only exposed dogs. Taking into account the entire concentration-time-effect relationship 23.6 and 20.6 mg/m3 were estimated to be the threshold concentrations to cause 0.8% MetHb following a 4 and 8h exposure period, respectively. The C(n)xt analysis of MetHb formation is consistent with a concentration-dependent restoration kinetics of MetHb suggesting that results from high level exposures cannot readily be extrapolated to low-level exposures. In summary, this study demonstrates that for aniline, an agent known to be bioactivated by a hepatic first-pass metabolism, the rate of delivery and uptake appears to be decisive for the extent of MetHb formation. Carry-over effects related to erythrotoxicity or Heinz body formation were not observed at any exposure level.
State aid and tax limitation in California

The combination of increased state aid and tax limitation has disappointed by failing to provide tax relief and better distribution of the tax burden.
Experiential Shamanism in the College Classroom: Rewards and Challenges

A brief description of an experiential approach to teaching shamanism and its pedagogical rewards is followed by a cautionary tale, detailing some challenges inherent in such experiential teaching in the public university environment. Issues addressed include the concerns of ethnic minorities, questions concerning the teaching of "religion,” pegagogical concerns, and issues of sufficient teacher training.
Cat color vision: The effect of stimulus size, shape and viewing distance

Abstract Four cats were trained on an intensity and color discrimination. Manipulations of stimulus size and viewing distance exerted a strong influence on the cats' color discrimination but had no effect on their discrimination of intensity. Variation of stimulus shape and orientation had no effect upon the cats' color discrimination beyond the influence of overall stimulus size. The finding that stimuli must subtend a large visual angle for the cat to perform well on a color discrimination accounts for much of the past discrepancy in behavioral studies.
The Varied Colors of Slave Heritage in West Africa: White American Stakeholders

Although White Europeans have played notable roles in shaping the contemporary political and social economy of Africa, it is Africans in the diaspora who actively trace their heritage to Africa. As...
An ethnographic investigation of the discourse processes of school science

In this article we drew from studies in the sociology of scientific knowledge (SSK) to create a new perspective for understanding school science. In doing so, we brought together ethnography and discourse analysis to study science-in-the-making in a physics classroom. We sought to document the social practices that constituted students' experimental data trials. To understand these interactions, we investigated the local conceptual ecologies created in the moment by student laboratory groups and the views of science made available across multiple classroom-based activities. Throughout the study we asked what counts as science in this science classroom. In doing so, we traced how science was portrayed and interactionally acknowledged across the shifting sociocultural contexts that constitute this high school physics class studied. © 1997 John Wiley & Sons, Inc.
Stimulus context and absolute magnitude estimation: a study of individual differences.

The effect of stimulus context on absolute-magnitude-estimation (AME) judgments was examined by determining whether the loudness judgment of a tone is influenced by the intensities of other tones presented within the session. A group of 18 subjects was tested in separate sessions in which they judged stimuli within either a low (10–60 dBSL) or a high (40–90 dBSL) range of intensities. Examination of the results of individual subjects revealed that judgments of stimuli common to the two ranges were, in most subjects, unaffected or only slightly affected by the position of the range. The judgments of 2 subjects who failed to follow the instructions, however, showed very large context effects due to changing the stimulus range. The results of a second experiment, in which 22 subjects judged the loudness of tones within either a narrow (35–65 dBSL) or a wide (20–80 dBSL)range, revealed that, in all but 1 subject, the width of the range had no systematic effect on the loudness judgments of stimuli common to both ranges. This was also true 1 month later when 16 of the subjects returned to the laboratory to judge the loudness of tones within an even wider range of 10–90 dBSL. It was concluded that AME judgments are relatively insensitive to the potential biasing influences of stimulus context.
History of medical and biological ultrasound at the University of Pennsylvania.

Abstract We briefly review my early contacts with bioacoustics and the bioacoustic work at the University of Pennsylvania that took place from the early 1950s to 1975. It was carried out with E.L. Carstensen, K.Li,A. Smith, H.Pauly,J.Reid,P.Edmonds and many students. The emphasis was first on basic biophysical studies. The work with E.Carstensen and H. Pauly was primarily concerned with the mechanism causing the high absorption typical for tissues and cell suspensions. Macromolecular content was shown to be largely responsible for the absorption. Practical applications concerned the relative merits of electromagnetic and ultrasonic diathermy techniques. P. Edmonds extended the range of macromolecular studies to 100 MHz and initiated work on the attenuation in lung tissues. After J. Reid came to Pennsylvania, the development of echocardiography took place.
Home and the nation: Women, citizenship and transnational migration in postcolonial literature

This article engages with interdisciplinary theoretical approaches to globalization and migration, and argues for their rethinking through postcolonial literature. It contends that the representation of migrant women and refugees in Nadine Gordimer’s and Amitav Ghosh’s fiction shows that we need to re‐examine not only the dominant, popular ideologies of the nation as “home” and citizenship as “belonging” but also the relations between violence, citizenship, and capitalist dispossession that often drive migration.
Observation of a Ru-rich Heusler phase in a multicomponent Ni-base superalloy

Abstract A new, ordered L2 1 Heusler phase based on Ru 2 AlTa was identified in a heat-treated multicomponent Ni-base superalloy containing high ruthenium. Such a phase has not previously been observed in muticomponent Ni-base superalloys or in quaternary Ni–Al–Ta–Ru systems. The influence of solidification-induced microsegregation on the formation and distribution of the Heusler phase is discussed.
Optimal source control and resolution in nondestructive testing

The paper considers the problem of damage detection arising in nondestructive testing. Applying currents on the boundary of a body and measuring the corresponding responses a conclusion should be made about the presence of damage inside the body. The detection problem is formulated using a variational approach as a generalized eigenvalue problem. The maximal eigenvalue defines the accuracy of the measurements, which is necessary to detect this distribution of damage. The damage can be detected if there exists such a current in the set of the currents prescribed by the conditions of the experiment that generates perturbation on the boundary greater than the noise level in measurements. To consider the worst case of detection, the damaged material should be distributed throughout the body in order to minimize the maximal eigenvalue of the spectral operator. An analytical estimate of the perturbation of the maximal eigenvalue is given, depending on the amount of damaged material.
“Put Your Money Where Your Love Is”: Parental Aid to Adult Children

Qualitative data are used to examine parents’ support to their adult children, and their motivations and feelings about it. The sample is 40 adult children and parents from four racial/ethnic groups: African-Americans, Asian-Americans, non-Latino Whites, and Latinos. Ideals of adult independence versus interdependence emerge as determinants of feelings about aiding adult children. The ambivalence concept provides the means to elucidate the tensions between these ideologies and children’s structurally shaped circumstances. Parental assistance to adult children was seen as acceptable for education, home ownership, and on behalf of young children, especially if the child was “working hard.” Parents still provided aid, however, even if these conditions were not met. In these situations, more intrafamilial tension characterized the aid transfer.
Internodal compartmentation of stem-infused [14C]sucrose in sweet and grain sorghum

Stem infusion was evaluated for quantifying downward movement, intracellular allocation, and interorgan partitioning of assimilate in sweet and grain sorghum [Sorghum bicolor (L.) Moench] stems during mid-grain fill and post-black layer. Sucrose concentration did not vary below the site of infusion with [14C]sucrose, although gradients of intracellular 80%-ethanol soluble and insoluble 14C-components were established in the stem. Variation in gradient steepness between cultivars resulted from aspects of parenchymal uptake or phloem uptake of sucrose and appears related to sucrose-concentrating ability. The introduced [14C]sucrose concentration gradient in stem tissue is useful for studying stem mechanisms that controls ink strength.
China Marches West: The Qing Conquest of Central Eurasia – Peter C. Perdue

In the author's own words, this work is “long,”“large,” and “sprawling” (xiv–xv). It is also magisterial and monumental. Drawing on archival and published sources as well as secondary scholarship i...
Speech and language alterations in dementia syndromes: Characteristics and treatment

Abstract Disorders of speech and language are commonly associated with dementia syndromes, and characteristics of verbal output can aid in the differential diagnosis of dementia and in clinical staging of dementing diseases. The cortical dementias such as Alzheimer's disease and Pick's disease are associated primarily with disturbances of language function. The subcortical dementias such as Parkinson's disease and progressive supranuclear palsy affect the motor aspects of speech, while sparing linguistic abilities. Patients with vascular dementias and post-traumatic encephalopathies usually have dysarthria with variable language abnormalities. Metabolic encephalopathies with dementia have incoherent verbal output with non-aphasic misnaming. Speech and language rehabilitation in dementia is little explored. Treatment strategies directed toward augmenting attention and comprehension and simplifying conversation will improve communication skills between the demented patient and the care-giver.
A micromechanical damage model for effective elastoplastic behavior of ductile matrix composites considering evolutionary complete particle debonding

A micromechanical damage model is presented to predict the overall elastoplastic behavior and damage evolution in ductile matrix composites. The effective elastic moduli of three-phase composites are predicted by a micromechanical formulation. To estimate the overall elastoplastic-damage responses, an effective yield criterion is derived based on the ensemble-volume averaging process and the first-order effects of eigenstrains due to the existence of spherical inclusions. The effects of random dispersion of inclusions are accommodated. The proposed effective yield criterion, together with the assumed overall associative plastic flow rule and the hardening law, constitutes the analytical foundation for the estimation of effective elastoplastic behavior of ductile matrix composites. An evolutionary interfacial particle debonding model is subsequently considered in accordance with the Weibull's statistical function to describe the varying probability of complete particle debonding. The interfacial debonding process is controlled by internal stresses of particles and a Weibull interfacial strength parameter. The completely debonded particles are regarded as voids for simplicity. The proposed elastoplastic-damage model is applied to the uniaxial, biaxial and triaxial tensile loadings to predict the various stress–strain responses. Efficient step-by-step iterative computational algorithms are also presented to implement the proposed damage model. Furthermore, the present predictions under various loading conditions are compared with other theoretical predictions and some available experimental data with modest particle concentrations.
"Cast Out from among the Saints": Church Discipline among Anabaptists and English Separatists in Holland, 1590-1620

AbstractThe tolerant atmosphere of The Netherlands attracted many persecuted Protestants to seek refuge there in the sixteenth and seveteenth centuries. This article focuses upon three significant Separatist groups that made their home in Holland in the years between 1593 and 1620—the Ancient Church led by Henry Barrow and John Greenwood, the proto-Baptists led by John Smyth and Thomas Helwys, and the proto-Pilgrims led by John Robinson—and examines their application and interpretation of church discipline, which they all saw as an essential mark of the true church. Furthermore, this study explores the practice of discipline among an indigenous Christian group with which the English Separatists had contact in Holland—the Waterlander Mennonites. After examining the shades of difference among these various separatist groups in Holland, the article explores how contact with indigenous Dutch Anabaptists impacted these English factions and the view of discipline they carried with them from Holland back to Engl...
Quaternary volcanic centres of the Turkana Rift, Kenya

Abstract Three small islands (North, Central and South Island) rise above the surface of Lake Turkana in northern Kenya. They represent the tops of Quaternary volcanic centres aligned along the axis of the Turkana Rift. They are links in the continuous chain of axial volcanic centres that run the length of the Eastern Branch of the East African Rift and represent the most recent additions to the architecture of the Rift. Mapping and petrographic studies reveal that the three island volcanic centres have many similarities in their general stratigraphy, structure, and geologic history; however, there are significant differences in relative lithologic abundances and compositions among them. The island volcanic centres are situated near the centres of each of a series of half-graben that are linked together along the length of the Turkana Rift. Estimates of the volumes of basaltic and intermediate volcanic components coupled with likely fractionation histories suggest that significant mafic-ultramafic intrusive complexes underlie the island volcanic centres. These are probably just the most recent additions to magmatically thickened, but mechanically thinned crust in this section of the East African Rift.
Imperceptible incomplete neutralization: Production, non-identifiability and non-discriminability in American English flapping

Abstract Flapping in American English has been put forward as a case of incomplete neutralization—in other words, /d/-flaps and /t/-flaps differ at the phonetic level. This paper first presents a production experiment which shows that, in line with previous work, flapping in American English is incompletely neutralizing: vowels before /d/-flaps are slightly longer than those before /t/-flaps—even in nonce words. Early studies on the perceptibility of this difference, almost exclusively identification tasks, have shown mixed results. However, recent identification experiments (including one reported here) show that listeners are unable to properly categorize /d/- and /t/-flaps. Listeners’ poor performance on identification tasks can be due to two factors: either (a) listeners’ grammars lacking the relevant phonological categories, or (b) an effect of the type of perception tasks employed. In a 2AFC discrimination task presented here, listeners were unable to distinguish between /d/- and /t/-flaps, suggesting that poor perception performance generalizes to multiple task types.
On the use of splines for the numerical solution of nonlinear two-point boundary value problems

Cubic splines on splines and quintic spline interpolations are used to approximate the derivative terms in a highly accurate scheme for the numerical solution of two-point boundary value problems. The storage requirement is essentially the same as for the usual trapezoidal rule but the local accuracy is improved fromO(h3) to eitherO(h6) orO(h7), whereh is the net size. The use of splines leads to solutions that reflect the smoothness of the slopes of the differential equations.
Responses of fetal ovine systemic and umbilical arteries to angiotensin II.

Angiotensin II (ANG II) contracts umbilical arteries and has been hypothesized to regulate fetal blood pressure primarily by altering umbilical vascular resistance. To determine whether systemic arteries in term fetal sheep are sensitive to ANG II, isometric contraction of endothelium-intact isolated fetal renal, mesenteric, and umbilical arteries in response to ANG II was studied. ANG II (10−7 M) elicited contractile responses in all three vessels (43 ± 8%, 99 ± 21%, and 105 ± 5% of the maximal response seen with 90 mM KCl for renal, mesenteric, and umbilical arteries, respectively). The time course of the contractile responses differed among the vessels: renal and mesenteric arteries exhibited rapid transient contraction followed by relaxation, whereas umbilical artery displayed a more slowly developing but sustained contraction (1 ± 0%, 3 ± 1%,and 93 ± 4% of maximal contractile response at 5 min, for renal, mesenteric, and umbilical arteries, respectively). The AT1 receptor antagonist, losartan (10−6 M), abolished contractile responses in renal and mesenteric arteries but only slowed the contraction in umbilical artery in response to ANG II and had no effect on maximal tension. AT2 receptor blockade (PD 123319, 10−7 M) had no significant effect on the response to ANG II in any vessel. Indomethacin (10−6 M) significantly potentiated contraction to ANG II in renal and mesenteric but not umbilical arteries. Northern and Western blot analyses demonstrated the presence of AT1 mRNA and protein in all three vessels. Immunostaining for the AT1 receptor was present in endothelium and the tunica media. These findings demonstrate the AT1 receptor is present and functionally active in fetal systemic arteries and are consistent with previous findings that the umbilical circulation displays a greater responsiveness to ANG II than the systemic vasculature.
Waste not, want not: a case for tRNA repair.

New work shows that a toxin that normally kills the yeast Saccharomyces cerevisiae by cleavage of tRNA substrates can be neutralized by RNA ligases that repair the damage, suggesting that these ligases may have a more general role in tRNA repair in the cell.
Social Media and Military Families: A Perspective

The role that social media plays in the lives of military families is enormous, whether the service person is on duty in the United States, overseas, or in a war zone. It also plays a role in the reintegration of military personnel into civilian life. Definitions and concepts of social media, health, and well-being are presented. The authors examine the military response to the phenomena of social media. The authors raise questions about the future role of research in documenting the potential effects of social media on the psychosocial health and well-being of service men and women and their families.
Multilayer films of CoCrTa for perpendicular recording media

Multilayer structures of alternate magnetic and non-magnetic CoCrTa alloys have been prepared in which the magnetic properties can be widely varied by changing the magnetic layer and interlayer thicknesses, In this way, one example has shown that enhanced perpendicular anisotropy can be achieved as demonstrated by an increase in perpendicular coercivity Hc( \perp ) and a decrease in longitudinal coercivity Hc(&dlor.). This condition is desirable for application in perpendicular recording media. In addition, a second example has shown that by using much thinner layers (≃15 nm) it is possible to produce a structure in which the magnetization is longitudinal with a very low coereivity of 1.5 Oe. Such soft magnetic films with high Ms and low Hc(&dlor.) can be used as underlayers for perpendicular recording media in order to enhance the efficiency of pole heads.
The role of dicarboxylic anion transport in the slower Ca2+ uptake in fetal cardiac sarcoplasmic reticulum.

ABSTRACT: Sarcoplasmic reticulum- (SR-)mediated Ca2+ transport is slower in the fetal heart compared with the adult. Virtually all previous studies of cardiac SR Ca2+ transport were performed in the presence of oxalate, a dicarboxylic anion that is cotransported with Ca2+ in skeletal muscle SR. If anion transport is developmentally regulated in cardiac SR, this could explain, in part, the previously reported results. The purposes of this study were to establish the presence of an SR dicarboxylic anion transport process in the rabbit heart and to determine if the perinatal changes in SR Ca2+ transport occur in a dicarboxylic anion-dependent and/or independent manner. In isolated fetal and adult rabbit cardiac SR membranes, we measured Ca2+ ATPase rates and 45Ca2+ uptake in the presence of the dicarboxylic anions maleate and succinate compared with the zwitterionic buffer PIPES, to which cardiac SR is essentially impermeable. We also measured 14C-succinate uptake by fetal and adult SR membranes. Anion-independent Ca2+ ATPase activity and net 45Ca2+ uptake were significantly lower in the fetal SR membranes than in the adult. Maleate and succinate increased the Ca2+ ATPase rates in the fetal and adult SR, but the effect was significantly greater in the adult. Maleate and succinate stimulated earlier attainment of maximal net Ca2+ uptake in the fetal and adult SR, suggesting that these dicarboxylic anions stimulated the rate of Ca2+ accumulation. Maleate and succinate significantly increased the maximal net Ca2+ uptake in the adult SR, but not in the fetus. The percentage of stimulation of Ca2+ uptake by maleate and succinate was similar in the fetal and adult SR. Dicarboxylic anion transport, as estimated by 14C-succinate uptake, was significantly lower in the fetus. The previously reported slower Ca2+ uptake rate in the fetus is related to dicarboxylic anion-dependent as well as independent mechanisms. The results provide firm support for the presence of a cardiac SR dicarboxylic anion transport process in rabbits that is developmentally regulated. These results also support the previously reported developmental regulation of the SR Ca2+ pump.
The Henry Jackson Memorial Lecture

This lecture reviewed selected types of experiments carried out in our laboratory which are relevant to the interpretation of clinical disorders. From an analysis of ventricular pressure pulses, inferences were drawn as to basic determinants of cardiac performance in experimental conditions simulating those which arise clinically. The analysis included alterations in ventricular contraction patterns produced by pericardial effusion, hypervolemia, oligemia, arterial hypertension of peripheral origin and that due to coarctation of the aorta, aortic and pulmonary stenosis, idioventricular rhythms, ventricular alternation, coronary occlusion and myocardial ischemia, aortic regurgitation, and mitral insufficiency.
The solubility and surface activity of the Ceratocystis ulmi toxin cerato-ulmin

The glycoprotein cerato-ulmin is one of several toxic metabolites isolated from Ceratocystis ulmi , the causal agent of Dutch elm disease. We present a number of physico-chemical measurements on cerato-ulmin in water and in ethanol/water. Surface tension measurements in water reveal cerato-ulmin to be surface active, even at concentrations as low as 3×10 −8 g cm −3 . This property relates also to the change in drop si"2e observed as cerato-ulmin elutes during chromatography. Light scattering shows that cerato-ulmin is only sparingly soluble in 70% ethanol/water (3·7×10 −4 g cm −3 ) and much less soluble in water. A limited X-ray analysis provides an estimate of the molecular weight and some information about the aggregation of cerato-ulmin. Few resonances appear in the 13 C nuclear magnetic resonance (n.m.r.) spectrum for cerato-ulmin in water. However, more resonances appear in 75% ethanol/water, and many more in. 6 m urea. From these results we gain insight as to the intra- and intermolecular interactions of the macromolecule in these solvents. A possible mechanism for the toxic effect of cerato-ulmin at ultra-low concentrations is put forth.
Nature and geochemistry of high molecular weight hydrocarbons (above C40) in oils and solid bitumens

Abstract Series of hydrocarbons ranging up to C 75 have been detected by high temperature gas chromatography (HTGC) in a number of geochemical samples, including oils and waxes precipitated in drill stem pipes. A saturated hydrocarbon fraction isolated from a fossil bitumen, ozocerite, and enriched in branched/cyclic compounds, was analysed by direct insertion probe mass spectrometry (DIP/MS) and showed the presence of cyclic structures in the high molecular weight region (>C 40 ). The asphaltene fractions isolated from the various samples were analysed by flash pyrolysis-high temperature gas chromatography (Py-HTGC). Similar distributions of high molecular weight hydrocarbons were produced from the asphaltenes of both the oils and waxes. In vitro simulation experiments of the asphaltene fractions produced a similar distribution of high molecular weight hydrocarbons as observed from Py-HTGC, suggesting that thermal breakdown of asphaltenes may be responsible for the production, or release, of some naturally occuring high molecular weight hydrocarbons.
Intersonic crack propagation in bimaterial systems

This paper describes experimental observations of various phenomena characteristic of dynamic intersonic decohesion of bimaterial interfaces. Two separate but complementary optical methods are used in conjunction with high-speed photography to explore the nature of the large-scale contact and mach wave formation at the vicinity of running cracks in two different bimaterial systems. Theoretical predictions of crack tip speed regimes, where large-scale contact is implied, are confirmed. Also, the theoretically predicted mach wave emanating from the intersonically propagating crack tip is observed. Direct visual evidence is also obtained for another traveling mach wave emanating from the end of the intersonically moving contact zone. Subsequently, a physical model for intersonic crack propagation along bimaterial interfaces is presented and ratified in view of recent experimental observations and theoretical developments. Finally, the paper presents very recent experimental evidence that shows crack tip speeds exceeding the intersonic regime and becoming clearly supersonic.
Analysis of dose response of trinitrochlorobenzene contact hypersensitivity induction in mice: pretreatment with cyclophosphamide reveals an optimal sensitizing dose.

Abstract A detailed dose-response curve has been established for induction of contact hypersensitivity (CH) in mice with trinitrochlorobenzene (TNCB). It was determined that in BALB/c, CBA/J, and C57BL/6 mice, the dose required to sensitize via epicutaneous application was between 1 and 10 ,μg TNCB. When doses of hapten of 200,μg or greater were painted on abdominal skin, CH responses were induced which were only marginally greater than responses induced by sensitizing doses of hapten in the 10–50-μg range, implying that no further dose-response relationship exists beyond 50 μg of hapten. However, in companion experiments, in which panels of mice were pretreated with cyclophosphamide, it was determined that sensitizing doses of hapten in excess of 50 μg induced both CH and concomitant induction of down-regulation of CH. Thus, at 200 μg or higher doses of TNCB, CH responses of cyclophosphamide pretreated mice were invariably more intense than in their untreated, hapten-painted cohorts. In the animals pretreated with cyclophosphamide, it was possible to see that a dose-response relationship continued to exist between the amount of epicutaneously applied hapten over a 200 μg to 14 mg range and the intensity of the CH induced. We conclude that the optimal dose for immunizing mice epicutaneously with TNCB is between 10 and 50,μg. This is considered optimal since animals sensitized in this manner display no evidence of concomitant down-regulation of their CH responses.
Insect Cells Encode a Class II α-Mannosidase with Unique Properties

Previously, we cloned and characterized an insect (Sf9) cell cDNA encoding a class II α-mannosidase with amino acid sequence and biochemical similarities to mammalian Golgi α-mannosidase II. Since then, it has been demonstrated that other mammalian class II α-mannosidases can participate inN-glycan processing. Thus, the present study was performed to evaluate the catalytic properties of the Sf9 class II α-mannosidase and to more clearly determine its relationship to mammalian Golgi α-mannosidase II. The results showed that the Sf9 enzyme is cobalt-dependent and can hydrolyze Man5GlcNAc2 to Man3GlcNAc2, but it cannot hydrolyze GlcNAcMan5GlcNAc2. These data establish that the Sf9 enzyme is distinct from Golgi α-mannosidase II. This enzyme is not a lysosomal α-mannosidase because it is not active at acidic pH and it is localized in the Golgi apparatus. In fact, its sensitivity to swainsonine distinguishes the Sf9 enzyme from all other known mammalian class II α-mannosidases that can hydrolyze Man5GlcNAc2. Based on these properties, we designated this enzyme Sf9 α-mannosidase III and concluded that it probably provides an alternate N-glycan processing pathway in Sf9 cells.
Cyclic changes in cAMP concentration and phosphodiesterase activity in a mammalian circadian clock studied in vitro

Abstract The mammalian suprachiasmatic nuclei (SCN) contain a circadian pacemaker that continues to keep 24-h time when isolated in vitro. We are investigating the role of cAMP in the cellular mechanisms underlying SCN function. We have previously shown that increasing intracellular cAMP during the subjective day resets the SCN pacemaker in the in vitro rat brain slice preparation 8, 20 . We now report that the level of cAMP fluctuates within the rat SCN under constant conditions in vitro. The level of endogenous cAMP is high during late day and late night, and low during early night. These changes in cAMP concentration are accompanied by opposite changes in phosphodiesterase activity; we detected no significant change in adenylate cyclase activity. These results provide further support for the hypothesis that cAMP is involved in circadian function in the SCN.
Numerical simulation of the regularized driven cavity flows at high Reynolds numbers

Abstract We present a numerical simulation of the unsteady incompressible flows in the unit cavity as well as in the rectangular cavity of aspect ratio 2 by using a second order projection scheme in time and a Chebyshev-Tau approximation for the space variables. The time-accurate discretization and the high accuracy of the spectral methods enable us to observe dynamical features not apparent in previous studies.
Facilitation of self-transcendence in a breast cancer support group: II.

Purpose/objectives To examine the feasibility and patterns of effectiveness of a breast cancer support group intervention specifically designed to facilitate self-transcendence views and perspectives that would enhance emotional and physical well-being. Design Pre-experimental design pilot intervention study with a quantitative approach to data analysis. Setting Survivor-established breast cancer resource center in Austin, TX. Sample Women with recently diagnosed breast cancer (N = 16) participating in 90-minute support group sessions that met weekly for eight weeks. Methods Theory-driven support group intervention facilitated by an oncology clinical nurse specialist, a psychotherapist, and a breast cancer survivor. Activities planned for individual sessions were based on self-transcendence theory, cancer support group literature, and the facilitators' extensive previous support group experience. Main research variables Self-transcendence, emotional well-being, physical well-being. Findings Good networking, coordination, and follow-up were essential for participant recruitment and retention throughout the intervention period. Although specific theory-driven activities were planned for group sessions, facilitators maintained flexibility in meeting immediate concerns of the participants. Relationships among participants' scores on study variables indicated an association between self-transcendence and emotional well-being. Scores on self-transcendence and well-being variables at the end of the intervention increased from baseline, but only functional performance status, mood state, and satisfaction with life reached statistical significance. Conclusions The pilot study was invaluable in providing direction for the conduct of future experimental studies. Implications for nursing practice Provides preliminary support for the use of theory-driven activities for promotion of self-transcendence views and behaviors within a cancer support group setting.
Derepressed beta-lactamase production as a mediator of high-level beta-lactam resistance in Pseudomonas cepacia

A mechanism of high-level resistance to readily and poorly hydrolyzable betalactam substrates in Pseudomonas cepacia was identified using a hypersusceptible, betalactamase-inducible, non-CF clinical isolate, 75–26, and a drug-resistant mutant derived from this strain. Inoculation of 75–26 onto agar containing 16 μg/ml of ceftazidime produced a stable, beta-lactam-resistant mutant at a frequency of 1.7 × 10−5. Baseline beta-lactamase production by a representative mutant isolate (75–26z) was almost 40-fold greater than the parent. Both strains produced major beta-lactamase bands with isoelectric points of 6.9, 7.8, 8.1, 8.5, and 9.2 by isoelectric focusing. Compared with the parental strain, multiple satellite bands associated with the major beta-lactamase bands were present in the mutant. Growth of an indicator strain, E. coli ATCC 25922, was inhibited by ceftazidime and piperacillin but was not inhibited after the compounds were preincubated with the beta-lactamase preparation from 75–26z. Preincubation of ceftazidime with beta-lactamase, followed by the addition of a beta-lactamase inhibitor, inhibited the growth of the indicator strain; piperacillin failed to inhibit growth of the indicator strain in a similar experiment. One mechanism of high-level resistance to both poorly and readily hydrolyzable beta-lactam substrates in P. cepacia is derepressed chromosomal beta-lactamase production. Pediatr Pulmonol 1988; 4:72–77.
High Frequency Radar Observing Systems in SEACOOS: 2002-2007 Lessons Learned

The aim of this paper is to provide a perspective on various radar systems based on the authors' collective SEACOOS experiences; and, more importantly, lessons learned from radar system deployments in differing venues where the dynamic range of the currents is large. The paper describes the basic radar premise and experimental designs, including results of the acceptance test along the West Florida Shelf. Time lines and a subset of interesting observations are also described. An overview of surface wave and wind measurements from HF radar techniques including directional waves is presented, and a summary of lessons learned followed by concluding remarks is also provided.
Active help found beneficial in wizard of oz study

Abstract Emerging AI techniques will make possible new intelligent help features, such as ‘active help’ (interrupting the user when appropriate) and ‘back channel’ communication (allowing users to send a message to a help system). An investigation was conducted to determine whether these features would be useful. In the experiment, users of a job scheduling application liked active help and performed better with it than did people without it. However, having a back channel was not particularly valuable to participants. Since developing this feature requires a lot of work, one should find evidence that it will be worth the effort before proceeding.
Training and Staff Development Issues in Developmental Disabilities

Many new community options have been created for individuals who only a few short years ago would have been considered too handicapped for such settings. Yet, each new opportunity also presents new challenges for service providers, many of whom have not been adequately trained to effectively meet these challenges. This article discusses some of the new roles for service providers in the future, including professionals, parents, and paraprofessionals; examines some issues pertinent to their training; and offers recommendations for correcting weaknesses in our current training and service systems.
Optical ‘bistability’ with single atom absorbers

We present observations of macroscopic switching of the optical field transmitted by a saturation-driven, single-atom cavity QED system induced by the atomic scattering of single photons.
Sugars and Free Amino Acids in Stored Russet Burbank Potatoes Treated with CIPC and Alternative Sprout Inhibitors

Glucose, fructose, sucrose and free amino acids were measured in stored Russet Burbank potatoes treated with sprout inhibitors isopropyl-N-(3-chlorophenyl) carbamate (CIPC), 1,4-dimethylnaphthalene (DMN), cineole and salicylaldehyde. Storage effects on sugar and amino acid contents were dependent on the specific sprout inhibitor. Salicylaldehyde treatment (200 ppm) produced a rapid increase of reducing sugar content and a greater amount of free amino acids than other treatments. A smaller amount of tyrosine was found in DMN (40 ppm) treated tubers compared to all other treatments. After 16 wk at 7°C, all potatoes treated with inhibitors had 10.5–11.8 mg/g dry weight reducing sugar content which would be considered acceptable for French fry processing.
Outpatient follow-up and rehospitalizations for sickle cell disease patients.

Background Rehospitalization rates are increasingly used as quality indicators for a variety of illnesses, including sickle cell disease. While one small, single center study suggested outpatient follow-up with a pediatric hematologist was associated with fewer rehospitalizations, no study has examined the effect of post-discharge outpatient follow-up on rehospitalization rates across ages and beyond a single site. Procedure This is a retrospective cohort study using Wisconsin Medicaid claims data for hospitalized children and adults with sickle cell disease from 2003 to 2007. The primary outcomes were rehospitalization at both 14 and 30 days after an index hospitalization for sickle cell pain crisis (ICD-9-CM codes 28242, 28262, 28264, 28269). Univariate survival analyses were performed based on outpatient visit, severe disease, asthma, and age. The Cox proportional hazards model was used for multivariate analyses yielding hazard ratios for the association between outpatient visits and subsequent rehospitalization rates. Results Of the 408 patients included, 42 (10.2%) patients were rehospitalized within 14 days and 70 (17.1%) were rehospitalized within 30 days. Multivariate analysis showed that an outpatient visit is associated with lower rates of both 30-day rehospitalization (Hazard Ratio (HR) 0.442; 95%CI: 0.330–0.593) and 14-day rehospitalization (HR 0.226; 95%CI: 0.124–0.412), with the majority of 30-day rehospitalizations occurring within 14 days. Conclusions For sickle cell disease, post-discharge planning should emphasize early follow-up to prevent subsequent hospitalization and improve care quality. Pediatr Blood Cancer 2012; 58: 406–409. © 2011 Wiley Periodicals, Inc.
Can the Sickness Impact Profile measure change? An example of scale assessment☆

Abstract The Sickness Impact Profile is a well known measure of functional status which has been validated as a measure of differences in function between patients, but not as a measure of within-patient change. To evaluate its performance as a measure of change, the Sickness Impact Profile was compared to a transition index that directly assesses intra-patient differences in maximal physical and emotional function. With the index, patients rate themselves as much better, slightly better, the same, slightly worse or much worse as compared to a previous assessment. When compared to the corresponding index ratings, Sickness Impact Profile subscale score changes for a rating of worse were of greater magnitude than those for a rating of better. The inherent variability of the Sickness Impact Profile score was estimated using the standard deviation of the score change for the index rating “the same”. For patients to be regarded as changed they had to lie outside the probability limits of this score change. Defined in this way, only patients who stated they were worse on the index were detected. Receiver operator characteristic curves were constructed and also demonstrated that deteriorations in function were more accurately detected. Using different score cutoffs, the best true positive rate (71%) was obtained using a one point change on the psychosocial subscale. This was accompanied by a 39% false positive rate. No score value appeared sufficiently accurate to be useful. Its apparent inability to detect improvements and deteriorations equally, and the wide standard deviations for a given change in function, may limit the use of the Sickness Impact Profile for following individuals over time. This analysis emphasizes the importance of validating all similar scales as measures of change before using them as outcomes in clinical research.
Modulation of active site electronic structure by the protein matrix to control [NiFe] hydrogenase reactivity

Control of the reactivity of the nickel center of the [NiFe] hydrogenase and other metalloproteins commonly involves outer coordination sphere ligands that act to modify the geometry and physical properties of the active site metal centers. We carried out a combined set of classical molecular dynamics and quantum/classical mechanics calculations to provide quantitative estimates of how dynamic fluctuations of the active site within the protein matrix modulate the electronic structure at the catalytic center. Specifically we focused on the dynamics of the inner and outer coordination spheres of the cysteinate-bound Ni–Fe cluster in the catalytically active Ni-C state. There are correlated movements of the cysteinate ligands and the surrounding hydrogen-bonding network, which modulate the electron affinity at the active site and the proton affinity of a terminal cysteinate. On the basis of these findings, we hypothesize a coupling between protein dynamics and electron and proton transfer reactions critical to dihydrogen production.