cssi/SciSciGPT-SciSciNet huggingface dataset:
Multiscale Finite Element Modeling of Alumina Ceramics Undergoing Laser-Assisted Machining

Alumina ceramics, due to their excellent properties of high hardness, corrosion resistance and low thermal expansion coefficient, are important industrial materials with a wide range of applications, but these materials also present difficulty in machining with low material removal rates and high tool wear. This study is concerned with laser-assisted machining (LAM) of high weight percentage of alumina ceramics to improve the machinability by a single point cutting tool while reducing the cutting forces. A multi-scale model is developed for simulating the machining of alumina ceramics. In the polycrystalline form, the properties of alumina ceramics are strongly related to the glass interface existing in their microstructure, particularly at high temperatures. The interface is characterized by a cohesive zone model (CZM) with the traction-separation law while the alumina grains are modeled as continuum elements with isotropic properties separated by the interface. Bulk deformation and brittle failure are considered for the alumina grains. Molecular dynamics (MD) simulations are carried out to obtain the atomistic structures and parameterize traction-separation laws for the interfaces of different compositions of alumina ceramics at high temperatures. The generated parameterized traction-separation laws are then incorporated into a finite element model in Abaqus to simulate the intergranular cracks. For validation purposes, simulated results of the multi-scale approach are compared with the experimental measurements of the cutting forces. The model is successful in predicting cutting forces with respect to the different weight percentage and composition of alumina ceramics at high temperatures in LAM processes.Copyright © 2014 by ASME
The clinical use of supine left lateral leg cycle ergometry for exercise electrocardiographic testing in women, as used in exercise echocardiography

Abstract Background Two-dimensional exercise echocardiography is commonly performed in the supine (SUP) left lateral posture (SLL) to optimize imaging quality. Objectives To assess the clinical use of SLL cycle ergometry, we determined the metabolic, cardiovascular, and hemodynamic responses during graded leg cycle ergometry in women, performed in SLL, commonly used during exercise echocardiography, and compared our findings with those obtained during upright (UP) and SUP leg cycle ergometry. Methods A total of 21 apparently healthy women performed leg cycle ergometry in 3 distinct postures (UP, SUP, and SLL). Results Peak oxygen consumption and peak achieved workload during SLL cycle ergometry were significantly lower compared with UP cycle ergometry, indicating that in SLL physical work capacity would be underestimated compared with that obtained for the UP and SUP postures. The peak heart rate was significantly lower in SLL and the peak systolic blood pressure higher, compared with UP. Maximal rate pressure product was not significantly different among the postures, indicating the equivalent value of SLL with regard to augmenting myocardial oxygen demand during exercise. Stroke volume (calculated from aortic Doppler flow integral) was higher at rest, and increased to a smaller extent during exercise, in the SUP posture and SLL compared with UP. Similar peak values were attained for the 3 postures. Conclusions SLL is not a suitable modality for the assessment of functional status or for the derivation of target heart rates for exercise training in UP posture. However, SLL leg cycle ergometry exercise provokes a comparable stimulus for the detection of coronary artery disease, as it will increase myocardial oxygen demand to the same extent as UP leg cycle exercise.
Fast diffusion in a room temperature ionic liquid confined in mesoporous carbon

We report a quasielastic neutron scattering study in the temperature range of 290 to 350 K of a room temperature ionic liquid, [bmim+][Tf2N−], in the bulk form and confined in the 8.8±2.1 nm diameter pores of a mesoporous carbon matrix. In both bulk and confined liquids, our measurements, which are sensitive to the dynamics of the hydrogen-bearing cations, detect two distinct relaxation processes related to the diffusion of the cations. We have found that the cations that do not become immobilized near the pore walls exhibit an enhanced rather than suppressed diffusivity compared to the cation diffusivity in bulk liquid. Our results provide first experimental observation of molecular diffusion in a room temperature ionic liquid in confinement which is faster than diffusion in the bulk liquid.
Veno-venous perfusion-induced systemic hyperthermia: Case report with perfusion considerations

Cancer cells are more susceptible to destruction by heat than are their normal counterparts. However, optimization of this hyperthermic susceptibility for selective cancer cell kill has been difficult to define and technically difficult to achieve. A whole-body hyperthermic technique veno-venous perfusion-induced systemic hyperthermia (VV-PISH) was designed in in vitro and in swine experiments to achieve selective hyperthermic cancer cell destruction. In this case report, VV-PISH is studied for its safety and therapeutic efficiency in a Food and Drug Administration (FDA) approved phase-I study, where hyperthermia is used to treat advanced (Stage III B or IV) lung cancer. VV-PISH, utilizing the ThermoChem HT system in an extracorporeal circuit, was used to induce hyperthermia to 42.5 degrees C sustained for 120 min. Cooling returned the body temperature to 37 degrees C. After completion of the treatment, the patient was transferred to the intensive care unit on a ventilator, norepinephrine and diuretics. The patient remained somnolent for 36 h, developed pulmonary congestion requiring an additional 48 h before extubation, was transferred to the intermediate unit on day 4 and discharged in good condition on day 8. He did experience hyperthermia-related shrinkage of his lung cancer; however, he succumbed 270 days after this treatment from further progression of this disease. Hyperthermia is not a benign therapy; management techniques have been developed that have ameliorated many of the problems associated with extremely high temperatures, but pathophysiology still exists. Using these techniques, VV-PISH can be safety implemented, albeit not without temporary sequelae and further hospitalization.
High temperature and low oxygen perturbations drive contrasting benthic recovery dynamics following the end-Permian mass extinction

The end-Permian mass extinction event was the greatest loss of biodiversity ever experienced on the planet. The event is thought to have been triggered by the initiation of the volcanic eruptions of the Siberian Traps. The five million year recovery interval that followed the extinction event was strongly influenced by the environmental effects of sustained volcanic eruptions including extreme temperature events and persistent global and regional oxygen minimum zones. The effects of these environmental perturbations on the paleoecological recovery of the benthic marine fauna were studied in two depositional units from the Southwestern United States representing two substages during the Early Triassic recovery. The Smithian Sinbad Limestone was influenced by high sea surface temperatures and contains a relatively high diversity fauna that exhibits extremely small body size. Gastropods that lived in this environment were size-limited, a possible result of metabolic stress due to extreme temperatures. These microgastropods were able to become dominate components of the benthic fauna by occupying niche space vacated by other taxa that were excluded by high temperatures. The Spathian Virgin Limestone shows evidence for low oxygen conditions. The resulting low diversity benthic fauna had a more ecologically complex community structure than the Smithian Sinbad Limestone including the occupation of epifaunal tiering space by crinoids. As the prevalence of aerobic facies increased through time, diversity, body size, and the complexity of faunal interactions also increased suggesting that low oxygen conditions were the limiting factor for the benthic recovery in that region. The differences in diversity and community structure between the two units highlight the importance of environmental and temporal differences in driving the recovery patterns of the benthic fauna following the extinction event. High temperature events and low oxygen conditions restricted the benthic fauna in different ways but both contributed to the delay in recovery from the end-Permian mass extinction.
ALGEBRAIC EQUATION AND ITERATIVE OPTIMIZATION FOR THE OPTIMIZED EFFECTIVE POTENTIAL IN DENSITY FUNCTIONAL THEORY

We further develop our recent direct method for the optimized effective potential (OEP) in density functional theory (DFT) [Yang and Wu, Phys. Rev. Lett.89, 143002 (2002)]. First, we show that the stationary condition in our optimization approach leads to a proper nonlinear algebraic equation for the OEP in a finite basis set, which differs from other finite basis set approaches. Then by constructing an approximate second derivative matrix of the energy functional in conjunction with the use of the Newton method, we significantly accelerate the convergence of the iterative optimization for OEP. Enhancement of the method is made in using the Tikhonov regularization method for the inversion of the second derivative matrix when it is singular or nearly singular and the direct inversion in the iterative space. It is shown that under a fixed stepsize condition, the optimization approach is equivalent to the self-consistent solution to the nonlinear algebraic equation for OEP. Because the approximate second derivatives are easy to compute and the iteration numbers are small now, the computation costs of OEP become comparable to that of regular DFT calculations as shown by calculations of some molecules, small and larger ones. We show how to find balanced results between energies and potentials when choosing a basis set for potentials.
What Is Learned under Difficult Conditions Is Hard to Forget: Contextual Interference Effects in Foreign Vocabulary Acquisition, Retention, and Transfer

Abstract In two experiments, participants were given, in an initial session, three trials of training on French-English vocabulary pairs and then were tested on these pairs. In a second session 1 week later, they were retested and then retrained on the same pairs. Both translation directions were employed (English-French and French-English). In Experiment 1, the vocabulary pairs were either blocked by category or mixed, and in Experiment 2, participants were pretrained on half of the French words before vocabulary learning. There was enhanced savings during relearning when initial learning involved the more difficult English-French translation direction or no pretraining on French words. Further, when learning involved the more difficult English-French translation direction or mixed pairs, forgetting across the 1-week delay was reduced.
Optimized O'Neill/Glaser Model for Human Population of Space and its Impact on Survival Probabilities

Two contemporary issues foretell a shift from our historical Earth based industrial economy and habitation to a solar system based society. The first is the limits to Earth s carrying capacity, that is the maximum number of people that the Earth can support before a catastrophic impact to the health of the planet and human species occurs. The simple example of carrying capacity is that of a bacterial colony in a Petri dish with a limited amount of nutrient. The colony experiences exponential population growth until the carrying capacity is reached after which catastrophic depopulation often results. Estimates of the Earth s carrying capacity vary between 14 and 40 billion people. Although at current population growth rates we may have over a century before we reach Earth s carrying limit our influence on climate and resources on the planetary scale is becoming scientifically established. The second issue is the exponential growth of knowledge and technological power. The exponential growth of technology interacts with the exponential growth of population in a manner that is unique to a highly intelligent species. Thus, the predicted consequences (world famines etc.) of the limits to growth have been largely avoided due to technological advances. However, at the mid twentieth century a critical coincidence occurred in these two trends humanity obtained the technological ability to extinguish life on the planetary scale (by nuclear, chemical, biological means) and attained the ability to expand human life beyond Earth. This paper examines an optimized O Neill/Glaser model (O Neill 1975; Curreri 2007; Detweiler and Curreri 2008) for the economic human population of space. Critical to this model is the utilization of extraterrestrial resources, solar power and spaced based labor. A simple statistical analysis is then performed which predicts the robustness of a single planet based technological society versus that of multiple world (independent habitats) society.
Microwave spectrum, electric dipole moment and barriers to internal rotation of trans and gauche-difluoromethylphosphine CHF2PH2

Abstract The microwave spectrum of difluoromethylphosphine, CHF 2 PH 2 , has been investigated in the region from 18.0 to 26.5 GHz. The spectra of two conformers have been identified. The ground state, and the first two excited vibrational states have been assigned for the more stable trans conformer, whereas the ground state and the first excited state have been assigned for the gauche form. The ground state rotational constants have been determined to be A =9264.411±0.003 MHz, B =4434.017±0.001 MHz, C =3244.497±0.001 MHz for the trans conformer, and A =9314.946±0.002 MHz, B =4378.067±0.002 MHz, C =3234.620±0.002 MHz for the gauche conformer. The following electric dipole moments were obtained from ground state Stark effect measurements: |μ a | = 1.42±0.01 D, |μ b | = 0, |μ c | = 1.86±0.1 D, |μ t | = 2.34±0.02 D for the trans conformer, and |;μ a | = 1.207±0.003 D, |μ b | = 0.639±0.008=D, |μ c | = 0.887±0.006 D, |μ t | = 1.63±0.001 D for the gauche conformer. The PH 2 torsional frequencies around the central carbon-phosphorus bound have been calculated from the relative intensities of the microwave lines in the excited vibrational states and the relative intensities of the two conformer lines. Energetically, the trans conformer is slightly favored over the gauche conformer by 18.4 cm −1 (52.6 cal mol −1 ). The data obtained on the two conformers are used to derive the potential energy function V (α) governing the internal rotation around the CP bond. The six Fourier coefficients were found to be V 1 =166±64, V 2 =−149±82, V 3 =673±159, V 4 =3.1±56, V 5 =9.6±46, and V 6 =23±78 cm −1 . This resulted in a potential barrier of 608±200 cm −1 between the trans and the two gauche conformers and 831±89 cm −1 between the two equivalent gauche conformers. These results are compared to the corresponding quantities in some similar molecules.
Selective Phosphorylation of Adult Tau Isoforms in Mature Hippocampal Neurons Exposed to Fibrillar Aβ

Abstract How senile plaques and neurofibrillary tangles are linked represents a major gap in our understanding of the pathophysiology of Alzheimer's disease. We characterized a hippocampal neuronal culture system in which tau undergoes maturation in vivo; rat neurons maintained in culture for more than 3 weeks replicated the splicing and phosphorylation changes that tau undergoes upon maturation in situ. Using this model system, we induced an Alzheimer-like neuritic dystrophy following the application of fibrillar β-amyloid. The dystrophy consisted of focal distortions and swellings within the neurites and an altered phosphorylation of the adult tau isoforms. Fibrillar β-amyloid induced the concomitant activation of MAP kinase and GSK3 β. The aberrant activation of several signaling pathways may lead to the abnormal phosphorylation of tau and neuritic degeneration.
Addressing sexual health behaviour during emerging adulthood: a critical review of the literature.

Aims and objectives In this critical literature review, we examine evidence-based interventions that target sexual behaviours of 18- to 25-year-old emerging adult women. Background Nurses and clinicians implement theory-driven research programmes for young women with increased risk of HIV/AIDS and sexually transmitted infections. Strategies to decrease transmission of HIV and sexually transmitted infections are rigorously evaluated and promoted by public health agencies such as the United States Centers for Disease Control and Prevention. While many interventions demonstrate episodic reductions in sexual risk behaviours and infection transmission, there is little evidence they build sustainable skills and behaviours. Programmes may not attend to contextual and affective influences on sexual behaviour change. Design Discursive paper. Methods We conducted a conceptually based literature review and critical analysis of the Centers for Disease Control and Prevention's best-evidence and good-evidence HIV behavioural interventions. In this review, we examined three contextual and affective influences on the sexual health of emerging adult women: (1) developmental age, (2) reproduction and pregnancy desires and (3) sexual security or emotional responses accompanying relationship experiences. Results Our analyses revealed intervention programmes paid little attention to ways age, desires for pregnancy or emotional factors influence sexual decisions. Some programmes included 18- to 25-year-olds, but they made up small percentages of the sample and did not attend to unique emerging adult experiences. Second, primary focus on infection prevention overshadowed participant desires for pregnancy. Third, few interventions considered emotional mechanisms derived from relationship experiences involved in sexual decision-making. Conclusions Growing evidence demonstrates sexual health interventions may be more effective if augmented to attend to contextual and affective influences on relationship risks and decision-making. Modifying currently accepted strategies may enhance sustainability of sexual health-promoting behaviours. Relevance to clinical practice This study provides nurses and public health educators with recommendations for broadening the content of sexual health promotion intervention programming.
MARRIAGE, DEPRESSION, AND COGNITION: UNRAVELING THE GORDIAN KNOT-REPLY TO ETTINGER ET AL.

Heim and Snyder (1991) explicitly applied a multidimensional assessment and data-analytic strategy to predict husbands' and wives' depressive symptoms from measures of marital disaffection, overt marital conflict, appraisals of relationship prognosis, characterizations of the spouse, and causal attributions. For both genders, the best single predictor of depression was a measure of marital disaffection—accounting by itself for approximately one third of the variance in subjects' depressive symptoms. Additional attributional predictors of depression for married women indicated the need for therapists to support wives' assertive expression of relationship concerns and confrontation of husbands' behaviors contributing to their distress. We reiterate the complex and recursive relationships among marital difficulties, depression, congnitive processes, and their antecedents and consequences and encourage focused research on components of this intricate puzzle.
Changes in the Tissue and Volume of the Stomachs of Calves Following the Removal of Dry Feed or Consumption of Inert Bulk

Summary Twelve Holstein heifer calves at 16 and 38 wk. of age were sacrificed after a growth study in which six had voluntarily consumed a high-concentrate diet and six a high-roughage diet. Ratios of hay to concentrate were 9:1 and 1:9. Four bull calves, two fed only milk and two fed milk while consuming shavings, also were studied. The objectives were to observe the effects of continuous consumption of a high-roughage, a high-concentrate, and an inert bulk diet on stomach muscle, mucosa, and volume, and to test the effect on stomach anatomy of reversing 16-wk.-old calves from the above ratios of hay to concentrate back to milk. Rumen papillae disappeared in the calves reversed to milk diets. The rumen collapsed around less fill, but maintained the same potential (water-filled) volume after 18 wk. of milk feeding, as had existed in calves of the same age on dry feed slaughtered at the beginning of the reversal period. This observation was interpreted as indicating a stasis, and not retrogression of reticulo-rumen volume. The amount of muscular tissue (fat-free dry) was less in the reversal calves, but the effect was not statistically significant. A stasis in omasal tissue growth occurred, and the abomasum continued to grow at the same rate as body size. Mucosal and muscular growth were independent. This was evidenced in three ways. (1) Reticulo-rumen mucosa retrogressed at a more rapid rate than muscle. (2) Muscular development was extensive in the absence of mucosal development in the calves consuming shavings. (3) Compared to muscle, well-developed mucosa contained lower nitrogen percentages when expressed on a fat-free dry matter basis (13.3 and 15.1%, respectively). Rumen papillae length was greater in the faster-gaining (high-concentrate) calves. Apparently, both rapid growth and papillary development were due to the higher energy levels consumed by these animals.
Rule of law and the size of government

If those with political power benefit from corrupt institutions, rulers might not adopt the rule of law so the ruling class can command a larger share of a smaller pie. An empirical analysis reveals that the size of government is larger in those countries that enforce the rule of law. If government expenditures provide some measure of the ability of the ruling class to command resources, this suggests that those with political power could benefit from imposing a fairer and more objective legal structure. Another conjecture is that those in power maintain corrupt governments to pay off their supporters and enhance their ability to remain in power. However, the rule of law is also positively associated with political stability, so better enforcement of the rule of law also enhances the ability of incumbent governments to remain in power.
Some new factors influencing user information satisfaction: implications for systems professionals

MIS researchers and professionals have identified user information satisfaction as a major objective of information systems development and implementation activities. In the absence of better evaluation criteria, user information satisfaction (or customer satisfaction) is often used as a criterion to evaluate the information systems department.In the MIS literature three major factors have been identified which can influence a user's satisfaction with her/his information systems. These factors are: the quality of information products (reports and screens), attitudes towards MIS staff and services, and knowledge and involvement level of user. This paper reports on a pilot study which aims to investigate two additional factors which may be relevant for user information satisfaction.The first additional factor is perceived fairness in the allocation of information systems and related resources to different user groups. Procedural fairness and distributive fairness have been identified as important for an individual's satisfaction in various non-MIS contexts. This study examines the relative role of fairness-related issues in an MIS context as determinants of user information satisfaction.The second factor relates to the impact of information systems design on the work environment of users. Role conflict and role ambiguity in the work environment are explored as a possible factor influencing user information satisfaction.
Plant growth-promoting rhizobacteria: effects on growth and nitrogen fixation of lentil (Lens esculenta Moench) and pea (Pisum sativum L.)

Abstract The potential of a number of putative plant growth-promoting rhizobacterial strains to enhance the growth and nitrogen fixation of western Canadian cultivars of lentil ( Lens esculenta Moench) and pea ( Pisum sativum L.) was assessed in field and laboratory studies. Nine strains were tested on a single cultivar of lentil (Eston) and pea (Trapper) in the field. None of the strains had any effect on growth of pea in the field, but in lentil inoculated with one or more of the rhizobacterial strains, there were significant increases in emergence, vigor, nodulation, C 2 H 2 reduction activity and root weight. Further laboratory studies conducted with the two best strains, G2-8 and G11-32 and lentil cv. Eston used four in vitro cultivation systems to determine the optimal conditions for plant growth enhancement. There was variation among experiments and cultivation systems but growth stimulation similar to that in the field was observed in trials with a sand column system. The best plant growth-promoting strain for Eston under in vitro conditions, G2-8, was then tested with lentil cv. Laird and plants inoculated with G2-8 had higher root and shoot dry weights and greater acetylene reduction than control plants in pot and sand column systems. Leonard jar and growth pouch systems were not satisfactory methods for observing growth enhancement of lentil by these bacterial strains, probably due to the slow growth rate of plants and watering method in the former system and the large seed size and short assay time in the latter. Results from these experiments suggest that strains such as G2-8 and G11-32 may be of value as adjunct inoculants for lentil, but effects are dependent on the cultivar and cultivation system used.
Quantitative Fourier transform infrared analysis of gas phase cigarette smoke and other gas mixtures

Abstract A new method for the analysis of selected components in complex gas mixtures has been developed utilizing a relatively inexpensive Fourier transform infrared spectrometer and a continuous flow gas cell. the method was used to monitor nitric oxide and nitrogen dioxide concentrations in cigarette smoke with time. Using multivariate least-square regression analysis, it is possible to simultaneously quantitate both NO and NO2, even in the presence of overlapping peaks. Using this method, the oxidation of nitric oxide in the presence of isoprene in cigarette smoke and in a model system was followed with time. the method also can be applied to other compounds in smoke or to any other gaseous mixture.
Vertical Moist Thermodynamic Structure of the Madden–Julian Oscillation in Atmospheric Infrared Sounder Retrievals: An Update and a Comparison to ECMWF Interim Re-Analysis

The large-scale vertical moist thermodynamic structure of the Madden–Julian oscillation (MJO) was documented using the first 2.5 yr (2002–05) of version 4 atmospheric specific humidity and temperature profiles from the Atmospheric Infrared Sounder (AIRS). In this study, this issue is further examined using currently available 7-yr version 5 AIRS data (2002–09) to test its dependence on the AIRS data record lengths, AIRS retrieval versions, and MJO event selection and compositing methods employed. The results indicate a strong consistency of the large-scale vertical moist thermodynamic structure of the MJO between different AIRS data record lengths (2.5 vs 7 yr), different AIRS retrieval versions (4 vs 5), and different MJO analysis methods [the extended empirical orthogonal function (EEOF) method vs the multivariate empirical orthogonal function (MEOF) method]. The large-scale vertical moist thermodynamic structures of the MJO between the AIRS retrievals and the ECMWF Interim Re-Analysis (ERA-Interim) products are also compared. The results indicate a much better agreement of the MJO vertical structure between AIRS and ERA-Interim than with the NCEP–NCAR reanalysis, although a significant difference exists in the magnitude of moisture anomalies between ERA-Interim and AIRS. This characterization of the vertical moist thermodynamic structure of the MJO by AIRS and ERA-Interim offers a useful observation-based metric for general circulation model diagnostics.
Bovine energy balance climatology and livestock potential in Nigeria

Abstract An insight into how an animal gains and loses heat over its interface is made, using a theoretical approach and employing four major climatic parameters—solarradiation, temperature, humidity, and wind. Two different types of cattle (the Jersey and the Shorthorn) are employed although conclusions in previous studies on other animals have also been employed where possible. The possibilities which exist for the application of energy balance climatology to livestock production potential have also been discussed. Maps of the storage term for March and July and the potential of the land to support both types of animals employed have also been included. The results show that the pattern of distribution of the storage term is generally zonal, although there are irregularities depending upon which of the climatic parameters employed has the greater influence. The distribution of the potentials also shows that the area around the Jos Plateau is best suited for any large scale livestock production, although with the application of the wind factor, the area around Ibadan proves an alternative.
Biarylpyrazole inverse agonists at the cannabinoid CB1 receptor: importance of the C-3 carboxamide oxygen/lysine3.28(192) interaction.

The biarylpyrazole, N-(piperidin-1-yl)-5-(4-chlorophenyl)-1-(2,4-dichlorophenyl)-4-methyl-1H-pyrazole-3-carboxamide (SR141716; 1) has been shown to act as an inverse agonist/antagonist at the cannabinoid CB1 receptor. Our previous mutant cycle study suggested that K3.28(192) is involved in a direct interaction with the C-3 substituent of 1 in wild-type (WT) CB1.1 However, these results did not establish what part of the C-3 substituent of 1 is involved in the K3.28(192) hydrogen bond, the carboxamide oxygen or the piperidine nitrogen. Furthermore, our previous calcium channel assay results for 5-(4- chlorophenyl)-3-[(E)-2-cyclohexylethenyl]-1-(2,4-dichlorophenyl)-4- methyl-1H-pyrazole (VCHSR; 2) (an analogue of 1 that lacks hydrogen-bonding capability in its C-3 substituent) showed that this compound acts as a neutral antagonist, a result that is in contrast to 1, which acts as an inverse agonist in this same assay.1 These results suggested a relationship between biarylpyrazole interaction with K3.28(192)...
Immune responses of human adults after oral and parenteral exposure to bovine serum albumin

Abstract Investigations were carried out to examine the possible causes of the low incidence and low levels of anti-BSA in human adults as compared to those of normal children. To determine if the reduced amount of BSA in the adult diet was an important factor, childhood levels of dietary BSA in the form of oral supplemental doses were administered to 17 normal human volunteers for 21 days. To learn if the manner in which dietary protein was catabolized by the gastrointestinal tract of the adult was a determining factor, selected individuals were also stimulated by intradermal injections of BSA. When anti-BSA was present before the experiment, there was a measureable antibody response following both methods of stimulation. The responsiveness of this group indicates that, among adults who retained the capacity to produce anti-BSA, the dose of antigen was an important variable in determining the amount of antibody actually produced. When no anti-BSA or very low levels existed before the experiment, the adults were unresponsive or hyporesponsive to both methods of stimulation. At least 80 per cent of these unresponsive adults had been synthesizing anti-BSA during childhood and should have resumed antibody production had their adult unresponsiveness been due to either a low dietary intake of BSA or the gastrointestinal conditions unique to adults. Circulating antigen was demonstrated in the sera of individuals without anti-BSA for as long as 21 days after intradermal injections of BSA. In subjects with trace amounts of anti-BSA prior to the intradermal injection of BSA, both BSA and anti-BSA were demonstrated to exist simultaneously in the serum for a minimum of 21 days. These data suggest that antigenantibody complexes can sometimes persist in the circulation for prolonged periods following the injection of relatively small doses of antigen into human subjects. None of the subjects demonstrated an immediate wheal-and-flare response, an Arthus reaction, or a tuberculin type of response when tested either before or after the experiment. Thus it appears that the low incidence of detectable anti-BSA among adults is due in part to an acquired immunological hyporesponsive state to BSA.
MicroRNA-301a mediated regulation of Kv4.2 in diabetes: identification of key modulators.

Diabetes is a metabolic disorder that ultimately results in major pathophysiological complications in the cardiovascular system. Diabetics are predisposed to higher incidences of sudden cardiac deaths (SCD). Several studies have associated diabetes as a major underlying risk for heart diseases and its complications. The diabetic heart undergoes remodeling to cope up with the underlying changes, however ultimately fails. In the present study we investigated the changes associated with a key ion channel and transcriptional factors in a diabetic heart model. In the mouse db/db model, we identified key transcriptional regulators and mediators that play important roles in the regulation of ion channel expression. Voltage-gated potassium channel (Kv4.2) is modulated in diabetes and is down regulated. We hypothesized that Kv4.2 expression is altered by potassium channel interacting protein-2 (KChIP2) which is regulated upstream by NFkB and miR-301a. We utilized qRT-PCR analysis and identified the genes that are affected in diabetes in a regional specific manner in the heart. At protein level we identified and validated differential expression of Kv4.2 and KChIP2 along with NFkB in both ventricles of diabetic hearts. In addition, we identified up-regulation of miR-301a in diabetic ventricles. We utilized loss and gain of function approaches to identify and validate the role of miR-301a in regulating Kv4.2. Based on in vivo and in vitro studies we conclude that miR-301a may be a central regulator for the expression of Kv4.2 in diabetes. This miR-301 mediated regulation of Kv4.2 is independent of NFkB and Irx5 and modulates Kv4.2 by direct binding on Kv4.2 3′untranslated region (3′-UTR). Therefore targeting miR-301a may offer new potential for developing therapeutic approaches.
Revisiting the life and scientific reputation of Ferdinand Vandeveer Hayden

Profiles of Rocky Mountain Geologists – a continuing series Hayden annoyed almost everyone he knew at one time or another; he thrived on spiteful controversy. —Mike Foster, 1994, p. 351 At the period of his greatest success Hayden was always the same unpretentious and enthusiastic seeker for knowledge. —Edward Drinker Cope, 1888 Had Congress created the United States Geological Survey (USGS) in 1877, rather than a year later, Ferdinand Vandeveer Hayden (Fig. 1) would likely have become the first director. He was the favorite. If this had happened, Hayden's reputation and prominence today would be completely different. Figure 1. F. V. Hayden, about the time of his directorship of the U.S. Geological Survey of the Territories, 1870. Courtesy of U.S. Geological Survey Photographic Library. By many accounts, Hayden was the most qualified of the principal candidates for the USGS directorship, a group that included Clarence King, John Wesley Powell, and George Montague Wheeler. Congressional support for Hayden's U.S. Geological and Geographical Survey of the Territories, and for Hayden as its leader, was greater than that for the Geological Exploration of the Fortieth Parallel (the King Survey), the Geographical Survey West of the 100th Meridian (under Wheeler, of the U.S. Army's Corps of Engineers), or the Geographical and Geological Survey of the Rocky Mountain Region (the Powell Survey). At the time, from his published studies and newspaper stories, Hayden was well known and respected both in the U.S. and in Europe. He managed many people and projects, and he raised the money to keep people in the field and in offices writing their reports, the publication for which he also arranged. During the 25 years or so of his exploration in the American West—up to about 1878—Hayden's publications exceeded in number and were frequently equal to or superior in quality to those …
Stuttering: Discoordination of Phonation with Articulation and Respiration

Complexity of phonatory and respiratory adjustments was systematically simplified in 30 adult stutterers under three speaking conditions: voiced, whispered, and articulated without phonation. Stuttering was reduced considerably when whispering and was practically eliminated when articulating silently. The possibility that stuttering consistently results from complexity of phonatory coordinations with articulation and respiration was strongly supported. Increased speaking rates under conditions that decreased stuttering seemed to be evidence that efficient rhythmical flow of speech is facilitated by simplification of phonatory and respiratory adjustments.
Lesbian Couples’ Relationship Quality Across the Transition to Parenthood

The transition to parenthood is a time of stress for many couples. Most research on the transition to parenthood has been conducted with middle-class, heterosexual couples. The current study uses multilevel modeling to examine predictors of change in relationship quality (love and conflict) during the transition to parenthood in 29 lesbian couples. Predictors included personality variables, work context variables, social context variables, and couple characteristics. Results suggest that personality and couple characteristics were important predictors of change in love, whereas personality and expected social support were salient predictors of change in conflict. The importance of research on this key life transition for lesbian couples is discussed.
56-Year-Old Woman With Positional Headache

© 2011 Mayo Foundation for Medical Education and Research A 56-year-old woman presented to the emergency department with a 10-day history of sudden-onset, severe positional headache. She had awoken to sharp pain in the back of her neck extending into the occiput that subsequently radiated to the frontal areas bilaterally. She rated her pain as 10 on the 10-point severity scale. There was no history of recent head trauma. She had experienced associated nausea, vomiting, vertigo, increased pain when upright, and improvement when supine. Her medical history was remarkable for limited cutaneous scleroderma with CREST syndrome (named for its associated symptoms: calcinosis, Raynaud phenomenon, esophageal dysfunction, sclerodactyly, and telangiectasia), type 2 diabetes mellitus, obstructive sleep apnea, hypercoagulable state with a positive lupus anticoagulant, hypertension with ischemic stroke, and multiple thromboses requiring long-term anticoagulation with warfarin. At presentation, all of her vital signs were within normal limits. Her physical examination was unremarkable, with the exception of hyperreflexia in the right upper extremity and bilateral lower extremities and left sixth cranial nerve palsy. Laboratory testing included a complete blood cell count, a metabolic panel, urinalysis, and measurement of troponin levels, which were all normal. The patient was noted to have a supratherapeutic prothrombin time with an international normalized ratio (INR) of 4.5 (target INR, 2.0-3.0).
The Relation of Bile and Pancreatic Juice to Duodenal Ulcer in Dogs

SummaryOf 15 dogs with complete external drainage of bile, all being supplied with bile by mouth or by a tube entering the upper intestine, duodenal ulcer was observed in 2 cases; only one instance of ulcer was noted in 19 dogs with exclusion of the pancreatic juice by separation of the pancreas from the duodenum.
De novo synthesis of long-wavelength absorbing chlorin-13,15-dicarboximides.

Chlorins bearing a six-membered imide ring spanning positions 13−15, commonly referred to as purpurinimides, exhibit long-wavelength absorption yet have heretofore only been available via semisynthesis from naturally occurring chlorophylls. A concise route to synthetic chlorins, which bear a geminal dimethyl group in the pyrroline ring, has been extended to provide access to chlorin-13,15-dicarboximides. The new route entails (i) synthesis of a 13-bromochlorin, (ii) palladium-catalyzed carbamoylation at the 13-position, (iii) regioselective 15-bromination under acidic conditions, and (iv) one-flask palladium-mediated carbonylation and ring closure to form the imide. In some cases the ring closure reaction afforded the isomeric (and readily separable) chlorin−isoimide in addition to the chlorin−imide. The resulting chlorin−imides and chlorin−isoimides exhibit long-wavelength absorption (679−715 nm) and emission (683−720 nm) in the far-red and near-infrared spectral region. The absorption of the chlorin−(is...
Transsulfuration in higher plants. Partial purification and properties of beta-cystathionase of spinach.

Abstract Extracts of a range of higher plants metabolized cystathionine predominantly by β-cleavage of homocysteine, pyruvate and ammonia. γ-Cleavage of cystathionine (to cysteine, α-ketobutyrate and ammonia) could not be demonstrated in the same extracts, and, if present, was less than 0.5% as active as β-cleavage. It follows that transsulfuration in higher plants resembles that in bacteria in proceeding predominantly, perhaps exclusively, in the direction cysteine → (cystathionine) → homocysteine. The physiological significance of the transsulfuration pathway in the de novo synthesis of homocysteine and methionine in higher plants is discussed. β-Cystathionase was purified over 400-fold from spinach leaves and some of its properties determined. The most active substrates are cystathionine, djenkolate and the mixed disulfide of cysteine and homocysteine. The effect of structure on the substrate activity is discussed, and a possible molecular conformation of active substrates is presented. The enzyme is competitively inhibited by β-cyanoalanine, and irreversibly inhibited by 5,5′-dithiobis-(2-nitrobenzoic acid) (DTNB) and N- ethylmaleimide . The substrate specificity of the plant enzyme resembles that of the bacterial enzyme, while the inhibitor sensitivity resembles that of the fungal enzyme.
Heme-protein vibrational couplings in cytochrome c provide a dynamic link that connects the heme-iron and the protein surface

The active site of cytochrome c (Cyt c) consists of a heme covalently linked to a pentapeptide segment (Cys-X-X-Cys-His), which provides a link between the heme and the protein surface, where the redox partners of Cyt c bind. To elucidate the vibrational properties of heme c, nuclear resonance vibrational spectroscopy (NRVS) measurements were performed on 57Fe-labeled ferric Hydrogenobacter thermophilus cytochrome c552, including 13C8-heme–, 13C515N-Met–, and 13C15N-polypeptide (pp)–labeled samples, revealing heme-based vibrational modes in the 200- to 450-cm−1 spectral region. Simulations of the NRVS spectra of H. thermophilus cytochrome c552 allowed for a complete assignment of the Fe vibrational spectrum of the protein-bound heme, as well as the quantitative determination of the amount of mixing between local heme vibrations and pp modes from the Cys-X-X-Cys-His motif. These results provide the basis to propose that heme-pp vibrational dynamic couplings play a role in electron transfer (ET) by coupling vibrations of the heme directly to vibrations of the pp at the protein–protein interface. This could allow for the direct transduction of the thermal (vibrational) energy from the protein surface to the heme that is released on protein/protein complex formation, or it could modulate the heme vibrations in the protein/protein complex to minimize reorganization energy. Both mechanisms lower energy barriers for ET. Notably, the conformation of the distal Met side chain is fine-tuned in the protein to localize heme-pp mixed vibrations within the 250- to 400-cm−1 spectral region. These findings point to a particular orientation of the distal Met that maximizes ET.
Evolving role of leukotrienes in the pathogenesis of viral infections, including otitis media

Otitis media (OM) is one of the most common childhood disorders and has been associated with an alarming rise in prevalence. Because medical therapy with antibiotics, antihistamines, decongestants, and corticosteroids has no demonstrable efficacy in the treatment of OM, the mainstay of treatment is surgical intervention. Although effective, surgical treatment is quite expensive and exposes patients to the risks associated with general anesthesia. Results of recent studies suggest that locally produced leukotrienes may play a role in the pathogenesis of OM. As such, a potential candidate for treatment of OM is the leukotriene receptor antagonist, montelukast, which has been approved by the US Food and Drug Administration for the treatment of asthma and/or allergic rhinitis. If proven effective, this drug’s safety/ convenience profiles and indication for children as young as 6 months of age would make it suitable for treatment of OM, and perhaps even prophylaxis of OM in at-risk populations.
Myths of gender

Female Choices: Sexual Behaviour of Female Primates. By Meredith F. Small. Cornell University Press: 1993. Pp. 245. $26.95. The Lemurs' Legacy: Evolution of Power, Sex, and Love. By Robert Jay Russell. Tarcher/Putnam: 1993. Pp. 274. $21.95.
Musculoskeletal: what's different in children? Running hard: acute hip pain: two patients.

This 12-year-old male was running hard at school when he felt a pop in his left hip and then there was almost immediate onset of pain. The severity of the pain initially was 8 out of 10. By the time he came to our emergency room (ER), it was 4 out of 10. However, it always was there and was aggravated by walking. It was a little better when he was lying down or sitting. Upon arrival to our ER, he was found to be in good health and the only problem was with his left lower extremity. He did not want to walk on it and complained of pain. On physical examination, there was relatively full movement of the left hip but not without assistance by the examiner. When asked where he was hurt, he sort of circled his palm around the outer part of the hip. On physical examination, he seemed to be most tender around the upper part of the iliac wing. Radiographs of the pelvis and hips were obtained (Fig. 1a). Do you see a fracture?
4-Hydroxy-3-methoxymandelic acid (HMMA) in the urine of normal and fasting subjects and in patients with colitis

Abstract An improved method of assay is described for 4-hydroxy-3-methoxymandelic acid (HMMA), involving paper electrophoresis followed by paper chromatography in two dimensions. Using this method, interfering substances were eliminated and the mean concentration of HMMA in the urine of 27 normal subjects on a varied diet was markedly lower than previously reported (1.3 μg/mg creatinine). For 8 colitis patients the mean value was 1.0 μg and for 5 normal subjects during 24-h periods without food, urinary HMMA was nil. Present results support the view that the presence of HMMA in human urine is dependent upon food intake, but this does not preclude a metabolic role for HMMA.