cssi/SciSciGPT-SciSciNet huggingface dataset:
Enriching Medical Student Learning Experiences

Objective:Medical students should develop skills in assessing their own learning needs and developing strategies to meet those needs. Medical curricula should be designed to provide active and enri...
Stability of Jiles-Atherton Anhysteretic Magnetization Curve Model for Magnetic Materials with Uniaxial Anisotropy

Anhysteretic magnetization curve plays the key role in modelling the characteristics of components made of soft magnetic materials. However, due to the positive feedback, for some set of parameters the most common model of magnetization curve might be unstable. Moreover, formal stability assessment of anhysteretic magnetization curve is sophisticated due to nonlinearities. Paper presents practical approach to stability assessment of Jiles-Atherton anhysteretic magnetization curve model for magnetic materials with uniaxial anisotropy. Results of this assessment enable the increase of efficiency of the process of identification of the model’s parameters, and as a result enable more efficient description of functional characteristics of inductive components with cores made of anisotropic soft magnetic materials.
Heritability of dietary traits that contribute to nephrolithiasis in a cohort of adult sibships

Kidney stones and their risk factors aggregate in families, yet few studies have estimated the heritability of known risk factors. Estimate the heritability of dietary risk factors for kidney stones. Dietary intakes were assessed using the Viocare Food Frequency Questionnaire in sibships enrolled in the Rochester, MN cohort of the Genetic Epidemiology Network of Arteriopathy. Measures of urinary supersaturation were determined using 24 h urine samples. Heritabilities and genetic correlations were estimated using variance components methods. Samples were available from 620 individuals (262 men, 358 women, mean (SD) age 65 (9) years). Dietary intakes of protein, sucrose, and calcium had strong evidence for heritability (p < 0.01) after adjustment for age, sex, height and weight. Among the significantly heritable dietary intakes (p < 0.05), genetic factors explained 22–50 % of the inter-individual variation. Significant genetic correlations were observed among dietary protein, dietary sucrose, and dietary calcium intakes (p < 0.001). Evidence from this relatively large cohort suggests a strong heritable component to dietary intakes of protein, sucrose and calcium that contributes to nephrolithiasis risk. Further efforts to understand the interplay of genetic and environmental risk factors in kidney stone pathogenesis are warranted.
Vibration Assisted AFM-Based Nanomachining under Elevated Temperatures using Soft and Stiff Probes

Abstract Atomic force microscope (AFM)-based nanomanufacturing, as a low-cost and easy-to-setup technique, enables high-resolution maskless nanofabrication processes for arbitrary nanopatterns, but there are strong needs to advance the nanopatterning processes. Thermal-mechanical AFM-based nanomachining process lower the normal forces to few hundreds of nanonewtons, but it requires special thermal probes. Vibration-assisted nanomachining process increases the tip lifetime but forces are still in the range of few hundreds of nanonewtons. We have innovated a system with both vibration and heated sample to achieve nanomachining process with lower normal forces. To provide cantilever selection guidance for this novel nanomachining system and to understand the effect of cantilever stiffness and sample temperature on feature dimensions, we used both soft and stiff probes for the nanomachining processes in this paper. We fabricated nanostructures with controllable shape dimensions were fabricated on 200 nm depth polymethyl methacrylate (PMMA) films by using both soft and stiff AFM probes with a few tens of nanonewtons normal forces in this novel AFM-based nanomachining system. Besides, we analyzed the effects of different machining parameters on the lithography performance, which helps to understand the machining parameters for fabricating nanopatterns of different dimensions. We also found that other than the setpoint force, the probe category and sample heating temperature significantly affect the dimensions of fabricated nanopatterns. And there is a statistically significant interaction effect between the spring constants of probes and the sample temperatures.
Understanding patient-provider discordance in adolescents with lupus: The role of pain and antidepressant medication use.

The current study examines depression and pain as potential contributors to patient-provider discordance in the assessment of lupus disease activity. The study conducted a secondary analysis of dat...
Understanding best practices: A look into homelessness related alcoholism

Comorbidity of substance use disorders and homelessness is an ever present issue in the United States. Determining the best course of treatment for these individuals remains challenging. Here we highlight dominant models and theories explaining the relationships between substance abuse (specifically alcoholism) and homelessness, considering how they can and should inform strategies in the treatment of individuals facing homelessness and alcoholism. We review several models that have been developed to guide intervention strategies, from the traditional 12 steps to managed alcohol programs within low income communities to choice based programming within homeless shelters and rehab facilities. Data suggest that the best strategy continues to be programs that enhance individuals’ community support through peer based interactions. Though the perfect treatment within this isolated population is yet to be determined, future research should help to identify viable candidates.
Comparing the Quality of Life after Brain Injury-Overall Scale and Satisfaction with Life Scale as Outcome Measures for Traumatic Brain Injury Research.

It is important to measure quality of life (QoL) after traumatic brain injury (TBI), yet limited studies have compared QoL inventories. In 2579 TBI patients, orthopedic trauma controls, and healthy...
Counts of psychrotrophic lipolytic bacteria in cow's raw milk samples from the aspect of technological quality.

The objective of the study was to analyze the relationship of psychrotrophic lipolytic bacteria in milk with the level of free fatty acids as an indicator of technological quality of milk on dairy farms with different management technology. The contamination of bulk samples of cow’s raw milk (n=110) by psychrotrophic lipolytic bacteria (PLiBC) and total counts of psychrotrophic bacteria (PBC) and mesophilic bacteria (TBC) were determined by a culture method in accordance with IDF standards. The content of free fatty acids (FFA) was determined by an extraction-titration method and somatic cell count (SCC) was determined by flow cytometry with fluorescence detection. The study was conducted throughout 2008 on 11 farms with different management technology (5 farms with loose littered cubicle housing with milking in a milking parlour; 3 farms with loose litterless slatted-floor housing with milking in a milking parlour; 3 farms with stanchion littered housing with an in-stall milking pipeline system). The correlation of PLiBC with FFA content was low (r=0.03; NS) and the correlation of SCC with FFA was similar (r=0.047; NS). The average FFA value of 32 mmol/kg fat was on the limit of the permissible maximum content for FFA for the extraction-titration method. However, a statistically significant relationship of FFA content (P<0.001) with the technology of stanchion housing with the in-stall milking pipeline system was proved where the highest average values of FFA and PLiBC were determined (42 mmol/kg fat and 1,935 CFU/ml – log 2.86; respectively) compared to loose littered cubicles (23 mmol/kg fat and 598 CFU/ml – log 2.58; respectively) and loose litterless slatted-floor housing with milking in a milking parlour (30 mmol/kg fat and 1,339 CFU/ml – log 2.84; respectively). The technology of milking in the in-stall milking pipeline system causes a higher mechanical stress of milk that results in physical damage of milk fat globule membranes and subsequent release of FFA from fat esters by lipases.
SU-E-J-198: Out-Of-Field Dose and Surface Dose Measurements of MRI-Guided Cobalt-60 Radiotherapy

Purpose: To measure quantities of dosimetric interest in an MRI-guided cobalt radiotherapy machine that was recently introduced to clinical use. Methods: Out-of-field dose due to photon scatter and leakage was measured using an ion chamber and solid water slabs mimicking a human body. Surface dose was measured by irradiating stacks of radiochromic film and extrapolating to zero thickness. Electron out-of-field dose was characterized using solid water slabs and radiochromic film. Results: For some phantom geometries, up to 50% of Dmax was observed up to 10 cm laterally from the edge of the beam. The maximum penetration was between 1 and 2 mm in solid water, indicating an electron energy not greater than approximately 0.4 MeV. Out-of-field dose from photon scatter measured at 1 cm depth in solid water was found to fall to less than 10% of Dmax at a distance of 1.2 cm from the edge of a 10.5 × 10.5 cm field, and less that 1% of Dmax at a distance of 10 cm from field edge. Surface dose was measured to be 8% of Dmax. Conclusion: Surface dose and out-of-field dose from the MRIguided cobalt radiotherapy machine was measured and found to be within acceptable limits. Electron out-of-field dose, an effect unique to MRI-guided radiotherapy and presumed to arise from low-energy electrons trapped by the Lorentz force, was quantified. Dr. Low is a member of the scientific advisory board of ViewRay, Inc.
Breech presentation at term

Abstract An analysis of 500 cases of breech delivery at the Mayo Clinic revealed greater fetal morbidity and mortality than occur with vertex delivery. Most patients are delivered vaginally with little or no difficulty; however, the hazard of delivery could be considerably reduced if more patients in whom fetopelvic disproportion is suspected or dysfunctional labor occurs were delivered by cesarean section to avoid traumatic vaginal delivery. No absolute figure can be given for the ideal cesarean section rate, but an incidence of 12 to 15 per cent would seem justifiable, particularly if applied to the present study in retrospect. Unpredictable cord prolapse remains a definite hazard to vaginal delivery, particularly with footling presentations, and prompt detection followed by immediate delivery by extraction or cesarean section is necessary. Total extraction delivery should be limited to emergencies during the second stage of labor and abolished as an elective procedure. In this series, the fetus of the primigravida fared better than the fetus of the multipara, which indicated a need to exercise greater concern and judgment in the management of the multipara.
A highly enantioselective hydrolysis of cis-3,5-diacetoxycyclopent-1-ene. : An enzymatic preparation of 3(R)-acetoxy-5(S)-hydroxycyclopent-1-ene.

Abstract Exposure of cis -3,5-diacetoxycyclopent-1-ene ( 3 ) to the hydrolase enzyme acetylcholinesterase (from electric eel) affords In 94% yield 3( R )-acetoxy-5( S )-hydroxycyclopent-1-ene ( 2 ) with an e.e. of 96% (greater than 99% e.e. after one recrystallization).
β-catenin, cartilage, and osteoarthritis

The early cellular events during the development of osteoarthritis (OA) are accelerated articular chondrocyte maturation and extracellular matrix degradation, which are usually seen in the weight-bearing region of articular cartilage. The results of our recent studies from transgenic OA mouse models indicate that upregulation of β-catenin signaling in articular chondrocytes is most likely responsible for the conversion of normal articular chondrocytes into maturing (arthritic) chondrocytes, which is associated with activation of chondrocyte maturational genes and matrix degradation. Conditional activation of the β-catenin gene in articular chondrocytes leads to an OA-like phenotype. Overexpression of Smurf2, an E3 ubiquitin ligase, also induces an OA-like phenotype through upregulation of β-catenin signaling. In addition, β-catenin upregulation was also found in articular cartilage tissues in patients with OA. These findings indicate that β-catenin plays a central role in articular cartilage function and that activation of β-catenin signaling may represent a pathologic mechanism for OA development.
Scale setting for αs beyond leading order

Abstract We present a general procedure for applying the scale-setting prescription of Brodsky, Lepage and Mackenzie to higher orders in the strong coupling constant αs. In particular, we show how to apply this prescription when the leading coefficient or coefficients in a series in αs are anomalously small. We give a general method for computing an optimum scale numerically, within dimensional regularization, and in cases when the coefficients of a series are known. We find significant corrections to the scales for Re+e−, Γ(B → Xue ν ), Γ(t → bW), and the ratios of the quark pole to MS and lattice bare masses.
Contraception: New developments

There is no ideal method of contraception and every method has its own side effects. Different groups of patients require different contraception - adolescents, older women, post- birth, post-abortion and those patients with concurrent medical problems.
A modular analog chip for feed-forward networks with on-chip learning

A feedforward artificial neural network (ANN) with learning capability in modular design is presented using CMOS circuits. We employ a modified error backpropagation continuous-time learning rule. A (nonlinear) analog Gilbert multiplier is used as a synapse and a wide-range transconductance amplifier is used as soma. For learning circuits, the, same multiplier is used for updating the weights. Test results demonstrate the successful operation of the chip. Finally, a modular chip design for a large scale implementation of feedforward ANN with learning is described. >
Blood platelet formation in vitro. The role of the cytoskeleton in megakaryocyte fragmentation

We have developed a unique in vitro model that promotes differentiation of megakaryocytes into platelets. When megakaryocytes isolated from guinea pig bone marrow were cultured on hydrated rat tail collagen gels, cells spontaneously formed elongated, beaded processes that fragmented to yield cytoplasmic pieces with the same size and internal composition as individual platelets. Addition of nocodazole at the initiation of cultures blocked process formation, while addition of nocodazole to cells with previously established processes resulted in their retraction. The addition of taxol to cultures resulted in abnormally thick processes that were tightly adherent to the underlying substratum, and did not bead or fragment. Cytochalasin D accelerated process formation and fragmentation of megakaryocytes cultured on collagen gels by twofold. On the basis of these results, we propose a model for platelet formation in culture that involves the following steps: adherence of megakaryocytes to the underlying extracellular matrix; dilation of the demarcation membrane system and breakdown of the actin-rich peripheral zone; microtubule-based extension of pseudopodia, which are no longer adherent to the substratum; and fragmentation into platelets by the coalescence and fusion of demarcation membrane vesicles with the plasma membrane. We feel that this distinctive culture system closely approximates thrombocytopoiesis in vivo, thus allowing detailed elucidation of this important process.
Aging-related defects are associated with adverse cardiac remodeling in a mouse model of reperfused myocardial infarction.

Mortality due to coronary artery disease is known to increase progressively with age. Older age was associated with a higher risk of in-hospital and post-discharge mortality in the GISSI-2 (Gruppo Italiano per lo Studio della Sopravivenza nell’Infarcto Miocardico 2) trial (1) and was a predictor of death and left ventricular dilation in patients with acute myocardial infarction (MI) enrolled in the SAVE (Survival and Ventricular Enlargement) trial (2). The exponential age-related increase in infarction-related mortality rates was not explained by larger infarcts (1). Although both clinical and experimental studies have demonstrated the adverse effects of senescence on cardiac function and remodeling after MI (2,3), the mechanisms responsible for these effects remain poorly understood. Post-infarction remodeling is closely intertwined with an inflammatory reaction that ultimately results in fibrous tissue deposition and formation of a scar. Inflammatory mediators regulate key cellular interactions in the infarct, modulating deposition and metabolism of extracellular matrix proteins in the wound. These actions have profound effects on the reparative response and ultimately determine the geometric characteristics of the infarcted ventricle by affecting the tensile strength of the scar (4–6). Both clinical studies and experimental investigations demonstrated aging-associated defects in inflammation and tissue repair. Cutaneous wounds heal more slowly in elderly patients as compared with younger patients (7,8) and show diminished expression of endothelial adhesion molecules (9). Furthermore, healing wounds in aged animals demonstrate a defective response to exogenously administered growth factors (10). We hypothesized that aging-associated alterations in inflammatory mediator expression and impaired responsiveness of senescent cells to growth factors might be important mechanisms responsible for defective infarct healing and adverse remodeling in elderly patients. With a mouse model of reperfused infarction, we compared the inflammatory and fibrotic response between young and old animals. Aging was associated with an attenuated post-infarction inflammatory response, delayed phagocytosis of dead cardiomyocytes, and markedly decreased collagen deposition in the infarct. These defects resulted in increased ventricular dilation and hypertrophy. Fibroblasts isolated from senescent animals exhibited a blunted response to transforming growth factor (TGF)-β stimulation, suggesting that impaired responsiveness to growth factors might mediate defective healing in senescent mouse infarcts.
Exercise arterial blood gas and end-tidal gas changes during acute airway obstruction.

Abstract In order to define more clearly the ventilatory, circulatory and mechanical alterations attendant upon application of an external expiratory airway obstruction during exercise, study of blood gas tensions, end-tidal trap gas tensions, ventilatory variables and diffusing capacity under such conditions has been carried out. Significant changes in PaO2 , PaCO2 , tidal trap gas composition and ventilatory factors were observed. Lack of variation in pre- and post-obstruction A-a O2 gradients and calculated physiological dead space implies that definable disturbances in ventilation-perfusion relationships are not occurring. Existence of a negative a-A CO2 gradient during steady-state exercise is confirmed and a magnification of the gradient during resistance breathing demonstrated. Comparison is made of arterial blood gas, end-tidal trap, and continuously monitored end-tidal CO2 tensions. No alterations in diffusing capacity were detected.
Expression of the murine CB2 cannabinoid receptor using a recombinant Semliki Forest virus

Abstract A recombinant Semliki Forest virus (SFV) RNA construct, SFV1-mCB2 RNA, was employed for the high-level expression of the murine CB2 (mCB2) cannabinoid receptor in baby hamster kidney cells. Biosynthetic radiolabel incorporation studies in concert with urea-sodium dodecylsulfate–polyacrylamide gel electrophoresis (urea-SDS–PAGE) and western immunoblotting revealed that two major proteins of approximately 26 and 40 kDa were produced by the construct. The 40 kDa product, but not the 26 kDa product, was glycosylated as determined by 2-deoxy- d -glucose incorporation and peptide-N-glycosidase F digestion analysis. Assessment of [ 3 H ]CP55940 ([ 3 H ]-(−)-cis-3-[2-hydroxy-4-(1,1-dimethylheptyl)phenyl]-trans-4-(3-hydroxypropyl)cyclohexanol) binding data for membranes of cells transfected with SFV1-mCB2 RNA indicated a Kd of 0.35±0.04 nM and a Bmax of 24.4±2.7 pmol/mg. A rank order of binding affinities for cannabinoids, which paralleled that reported for native mCB2 receptors, was observed. The CB2 receptor-specific antagonist SR144528 (N-[(1S)-endo-1,3,3-trimethyl bicyclo[2.2.1]heptan-2-yl]-5-(4-chloro-3-methylphenyl)-1-(4-methylbenzyl)-pyrazole-3-carboxamide) blocked binding of [ 3 H ]CP55940, while the CB1 receptor-specific antagonist SR141716A [N-(piperidin-1-yl)-5-(4-chlorophenyl)-1-(2,4-dichlorophenyl)-4-methyl-1H-pyrazole-3-carboxamide hydrochloride] had a minimal effect. These results indicate that the recombinant receptor expressed from SFV1-mCB2 RNA exhibits properties, including ligand binding features, that are consistent with those for the native mCB2 receptor. However, the presence of both 26 and 40 kDa receptor species is consistent with alternative translation from two AUG start sites using the SFV1-mCB2 RNA expression system.
Influence of location and staff knowledge on quality of retail pharmacy prescribing for childhood diarrhea in Kenya.

Background : Retail pharmacies are important sources of advice on pharmaceuticals in developing countries, where many purchasing decisions are unmediated by medical professionals. For childhood diarrhea, choice of drug sales in pharmacies has been found to be consistently poor, whether with or without prescription, as evidenced by a low use of effective oral rehydration salts (ORS) and high use of marginally effective or ineffective products such as antimotility agents, adsorbents, and antimicrobials. Little information is available about factors influencing prescribing by pharmacy personnel in these settings. This paper reports results of an analysis which examined the influence of rural versus urban location, neighborhood socio-economic status (SES), and clinical knowledge of pharmacy assistants on quality of prescribing in retail pharmacies in Kenya. Methods : Using WHO treatment guidelines, we measured quality of prescribing in childhood diarrhea as: (1) the proportion of client encounters in which ORS is prescribed (indicating higher quality practice); and (2) the proportion of visits in which an antidiarrheal product is prescribed (lower quality practice). We obtained data on prescribing in a simple case of childhood diarrhea using surrogate patient visits to 91 pharmacies located in the major urban area of Kenya (Nairobi) and four rural towns. Multivariate logistic regression was used to examine the association between pharmacy predictor variables and the quality of prescribing. Results : No consistent relationship was found between the clinical knowledge of pharmacy assistants and quality of prescribing. Controlling for number of products prescribed, gender of the assessor, and level of knowledge, multivariate analyses indicated that in comparison to rural pharmacies, the odds of prescribing ORS were significantly higher in parmacies located in high SES (OR = 4.7; 95% CI = 1.4, 16.1) or middle SES (OR = 4.5; CI = 1.9, 10.6) urban neighborhoods; the odds in low SES urban pharmacies were similar to those in rural areas (OR = 2.0; CI = 0.6, 6.2). The odds of prescribing antidiar-rheal products did not differ significantly in any geographic area. Conclusions : Location of a retail pharmacy in a rural area or in a low-income urban neighborhood was associated with suboptimal quality of prescribing as evidenced by lower use of ORS. No relationship between clinical knowledge and quality of practice was detected. Future research is needed to examine such factors as the influence of intra-pharmacy authority structure, perceived efficacy of pharmaceuticals, local patterns of physician practice, and economic incentives on the quality of prescribing. Copyright © 1996 Elsevier Science Ltd.
Theory of collective spin waves and microwave response of ferromagnetic nanowire arrays

We formulate the theory of the collective spin wave modes and the microwave response of arrays of ferromagnetic nanowires of cylindrical cross section, each magnetized parallel to the axis of symmetry. The theory is based on a multiple scattering approach, and may be applied to the regime where the diameter of the constituents is small enough that exchange enters the response importantly. The formalism can be applied to ordered arrays, or disordered arrays of nanowires. We present explicit results for the spin wave normal mode frequencies of a pair of nanowires, and for a linear array. The dispersion curves for the collective modes in the latter case show a dispersive collective mode which crosses and hybridizes with resonances in the individual cylinders. For a nanowire pair, and in the magnetostatic limit, we obtain a closed form expression for the collective spin wave modes in the limit as the wavevector parallel to the symmetry axis vanishes. Interestingly, the resonance does not split as the wires are brought together, but just shifts downward in frequency, from the value $\ensuremath{\gamma}{(H}_{0}+2\ensuremath{\pi}{M}_{s})$ appropriate to the isolated wire at large separations, to $\ensuremath{\gamma}[{H}_{0}{(H}_{0}+4\ensuremath{\pi}{M}_{s}){]}^{1/2}$ when the wires just touch.
Levamisole in chronic hepatitis: A favorable trend is not enough

A double-blind, randomized, controlled trial has been undertaken to evaluate treatment of chronic hepatitis type B with levamisole. Ten patients received levamisole (150 mg/day, 3 days/wk) and 10 received placebo until seroconversion to antibody to hepatitis B e antigen eventually occurred, or for a maximum of 18 mo. Final evaluation at 24 mo after starting treatment revealed that 60% of the patients in the levamisole group had become hepatitis B e antigen negative, 90% were hepatitis B virus–deoxyribonucleic acid negative in serum, and 8 of 9 (89%) patients had cleared hepatitis B core antigen from the liver. On the other hand, in the placebo group only 4 of the 10 subjects (40%) were hepatitis B e antigen and hepatitis B virus–deoxyribonucleic acid negative in serum and 3 of 8 (37.5%) of them became hepatitis B core antigen free in the liver. Moreover, in 8 patients of the treated group and in 4 of the control cases amino-transferase activities fell into the normal range. A liver biopsy specimen was obtained after treatment in 17 patients and 7 of 9 levamisole recipients showed marked improvement in hepatic histology, compared with 3 of 8 placebo recipients. These data show that patients treated with long-term levamisole therapy have a tendency toward normalization of aminotransferase activities and suppression of hepatitis B virus replication, suggesting that the drug may be of benefit in chronic hepatitis B e antigen-positive hepatitis.
Ontology Theory of Consciousness

The transgenic extension of a mouse's color vision and research in which the insertion of a gene enables blind mice to see provide a much firmer basis for a materialist theory of consciousness than has hitherto been available. Such seminal research offers empirical evidence that qualities are physical. In the Ontology Theory, consciousness is described as resulting from a process beginning with energies conveyed from noumena in the environment. The energies stimulate sense receptors which in a recursive exchange with memory result in qualities. The qualities consist of proteins or other neuronal molecules which, to the mind of the conscious individual, comprise semi-independent memory items (SIMIs), or phenomenal objects which are projected to the environment and are perceived as environmental objects. Thus, in the consciousness of the individual, environmental objects consist of the ontology of particular molecules.
Infrared Radiation of SF6AND its Application to Gas-Filled Double-Pane Windows

Interest in using sulfur hexafluoride (SF6 as a gas-fill in multipane windows has raised questions concerning the calculation of heat transfer rates through such windows. The infrared absorption characteristics of this gas make the heat transfer analysis much more complicated. In order to account for the absorption effect, we measured the spectral absorptivity of several infrared-active bands of sulfur hexafluoride at low resolution and a temperature of 298 K. We correlated the spectral absorption data with the Edwards exponential wide-band model and with the Elsasser narrow-band model, and incorporated the wide-band model into a one-dimensional, finite-element heat transfer model. The finite-element heat transfer model considered combined conduction and radiation effects in a double-pane window, and was used to evaluate the overall heat transfer coefficients of double-pane windows filled with SF6; CO2, or air. The numerical results show good agreement with the experimental results
The effects of immigration in a distorted two-sector economy.

This paper examines the income, employment and distributional impact of immigration on a recipient economy facing an administered wage distortion. It is found that immigration increases the unemployment rate of the native population and shifts income distribution against labor and in favor of the nonlabor input. Its effect on the total income of the non-immigrants is, however, ambiguous, and depends on the relative importance of the increase in unemployment versus the net increase in the rent received by the owners of the non-labor input.
MASS SPECTROGRAPHIC ANALYSIS OF ERBIUM, CERIUM AND LUTETIUM METAL

Abstract A mass spectrograph equipped with an r.f. spark ion source and a photographic plate ion detection system is being used to obtain semiquantitative analyses of homogeneous bulk impurities in commercially available rareearth metals. Analyses of 50 elements in 6 different erbium samples, 41 elements in 2 different cerium samples, and 26 elements in 5 different lutetium samples have been made using a detection limit range of 0.1–20 p.p.m. atomic. Results for hydrogen, carbon, nitrogen, and oxygen by microcombustion and neutron activation techniques are in poor agreement with the mass spectrographic results. Nonhomogeneity can be a serious problem and an important factor when purity is stated for a given rare-earth metal.
The tau heavy lepton—a recently discovered elementary particle

This review recounts the history of the discovery of the tau heavy lepton. Evidence for the tau being a lepton is summarised and the known properties of the tau are discussed.
AN INVESTIGATION OF THE STATISTICAL RELATIONSHIP BETWEEN THE 345 KV TRANSMISSION LINE LENGTH AND THE OUTAGE RATE

Finding the factors that are related to varying transmission outage rates has been one of the major concerns of the reliability practitioners in the electric power industry. One of the potentially influential factors is the length of the transmission line. In this paper, a random effects Poisson regression model is used to quantify the relationship between the outage rate to the transmission line length. The method suggested is applied to analyze two sets of the 345 KV transmission line outage data of the Commonwealth Edison Company: group 1 contains transmission lines that had been installed before January 1974; group 2 consists of the lines that have been installed since January 1974. Results indicate that in both cases there is a significant log linear relationship between the transmission line outage and the line length. However, the annual outage rate elasticity of transmission lines of group 2 turns to be 0.33 while that of group 1 is 0.64. This would imply apparent quality improvement on the transmission lines in group 2.
A stochastic theory for the emergence and the evolution of preference relations

Abstract This paper presents a theory describing the emergence and the evolution of preference relations over (real) time. The subject or consumer is regarded as immersed in a random environment of the Poisson type. Events arise at random times, which consist of tokens of information about the alternatives. Some of these tokens have the potential to create or modify some edges of the graph of the preference relation. General axioms are given that lead to a stochastic process of Markovian character. In a special case of these axioms, a random utility model is obtained as an asymptotic result. Specifically, it is shown that the Markov process converges to a random walk on a unique ergodic set composed of all the rankings of the set of objects. Precise asymptotic results are derived and the explicit expression for the probability distribution on the set of rankings is obtained. In another special case, the asymptotic random walk is on the set of all weak orders. It is also shown how the theory can account for the resemblance between the preference relations obtained, from the same subject, at time t and t + δ.
Aging, grey matter, and blood flow in the anterior cingulate cortex.

Abstract The anterior cingulate cortex (ACC) is thought to be the neuroanatomical interface between emotion and cognition. Because effective emotion–cognition interactions are essential to optimal decision making, clarifying how the functionality of the ACC changes in older age using functional imaging holds great promise for ultimately understanding what contributes to the psychological changes occurring in late life. However, the interpretation of functional imaging studies is complicated by the fact that aging is associated with changes in grey matter volume and in the cerebral vasculature. In the present study, we obtained high-resolution structural magnetic resonance (MR) imaging data and quantitative blood flow images to examine the association between aging, blood flow, and grey matter volume in the ACC. Twenty-six healthy individuals between 25 and 79 years of age underwent quantitative [ 15 O]water positron emission tomography (PET) imaging. The ACC was traced onto tissue-classified images derived from T1- and T2-weighted MRIs using previously defined methods. The ACC was divided into dorsal, rostral, and subgenual regions. Age was negatively correlated with blood flow in dorsal and rostral ACC regions. Effects were weaker but in a similar direction for the subgenual ACC. While older age and lower blood flow were both associated with smaller rostral ACC grey matter volumes, mediation analysis revealed that grey matter volume only partially mediated the effect of age on blood flow in the rostral ACC. Neural alterations not detectable on MR images may lead to reduced blood flow due to fewer and/or less metabolically active neurons. Alternatively, lower blood flow may be a cause, rather than a consequence, of smaller grey matter volume in the ACC.
THE EFFECTS OF BACKGROUND ON THE EQUAL VALUE GRAY SCALE

In this study a psychophysical experiment was conducted in order to determine to what extent changes in background reflectance affect the selection of equal appearing gray tone intervals. This is important to know because cartographers frequently use a series of gray area tones to represent quantitative data, and it is essential that the map reader perceive a direct correspondence between the value of the gray area tones and the quantities they represent. The results of the experiment indicated that changes in background reflectance had no significant effect on the selection of the darker gray tones, but as the value of the gray tones increased, so did the effects of background. The power formula developed by Stevens and Galanter provided a good approximation to the experimental data for white and black backgrounds, and can be used to construct a series of equal appearing gray tone intervals. The potential of a reformulated power function based on adaptation-level theory to predict background effects was ...
“Grab the Signatures and Run”: Federal Unity Strategy in Canada from the Referendum to Patriation

Whether as a traumatic event or great accomplishment, the legacy of the First Ministers’ Conference of 1981 lives on in Canadian politics. Constitutional negotiations among the prime minister and provincial premiers in 1981 produced the only “packaged” agreement since Confederation to achieve even the minimal support necessary to achieve ratification. The resulting Constitution Act of 1982, which included the Charter of Rights and Freedoms, remains in place and is the principal manifestation of intergovernmental bargaining from over two decades ago. This study reevaluates the strategic interaction and conflict processes that took place between Ottawa and the provinces in negotiations leading up to that fateful November 1981 conference. We apply the sociological framework for assessment of the dynamics of identity contention adopted from [McAdam, Tarrow, and Tilly (2001)][1] and find tentative support for its propositions. After an overview of the article's agenda, we present an analytic framework for the study of conflict processes. Second, the background to the constitutional crisis of 1980-81 is summarized. Using the analytic framework, the third section focuses on the federal strategy in the crisis as suggested by minutes from cabinet meetings, and the fourth section examines key events of the First Ministers Conference of November 1981. Fifth, and finally, the contributions of the preceding sections are summed up and ideas are put forward for further research. [1]: #ref-49
SYNTHESIS AND ENANTIOSELECTIVITY OF CYCLOPROPAVIR PHOSPHATES FOR CELLULAR GMP KINASE

Enantiomeric cyclopropavir phosphates (+)-9 and (−)-9 were synthesized and investigated as substrates for GMP kinase. N2-Isobutyryl-di-O-acetylcyclopropavir (11) was converted to (+)-monoacetate 12 using hydrolysis catalyzed by porcine liver esterase. Phosphorylation via phosphite 13 gave after deacylation, phosphate (+)-9. Acid-catalyzed tetrahydropyranylation of (+)-monoacetate 12 gave, after deacylation, tetrahydropyranyl derivative 14. Phosphorylation via phosphite 15 furnished, after deprotection, enantiomeric phosphate (-)-9. Racemic diphosphate 16 was also synthesized. The phosphate (+)-9 is a relatively good substrate for GMP kinase with a KM value of 57 μM that is similar to that of the natural substrates GMP (61 μM) and dGMP (82 μM). In contrast, the enantiomer (−)-9 is not a good substrate (KM 1200 μM) indicating a significant enantioselectivity for the GMP kinase catalyzed reaction of monophosphate to diphosphate.
UNC-45B Chaperone: The Role of its Domains in the Interaction with the Myosin Motor Domain

The proper folding of many proteins can only be achieved by interaction with molecular chaperones. The molecular chaperone UNC-45B is required for the folding of striated muscle myosin II. However, the precise mechanism by which it contributes to proper folding of the myosin head remains unclear. UNC-45B contains three domains: an N-terminal TPR domain known to bind Hsp90, a Central domain of unknown function, and a C-terminal UCS domain known to interact with the myosin head. Here we used fluorescence titrations methods, dynamic light scattering, and single-molecule atomic force microscopy (AFM) unfolding/refolding techniques to study the interactions of the UCS and Central domains with the myosin motor domain. We found that both the UCS and the Central domains bind to the myosin motor domain. Our data show that the domains bind to distinct subsites on the myosin head, suggesting distinct roles in forming the myosin−UNC-45B complex. To determine the chaperone activity of the UCS and Central domains, we used two different methods: 1), prevention of misfolding using single-molecule AFM, and 2), prevention of aggregation using dynamic light scattering. Using the first method, we found that the UCS domain is sufficient to prevent misfolding of a titin mechanical reporter. Application of the second method showed that the UCS domain but not the Central domain prevents the thermal aggregation of the myosin motor domain. We conclude that while both the UCS and the Central domains bind the myosin head with high affinity, only the UCS domain displays chaperone activity.
Iron deposits in the central nervous system of SJL mice with experimental allergic encephalomyelitis.

Abstract Iron has been proposed to promote oxidative tissue damage in multiple sclerosis (MS). In order to gain insights about how iron gets processed during MS, the deposition of iron was investigated in the CNS of mice with experimental allergic encephalomyelitis (EAE), which is a commonly used animal model of MS. Control mice (adjuvant only) and EAE mice (myelin basic protein plus adjuvant), were sacrificed at 4–8 days (preclinical phase), 10–13 days (clinical phase), or 18 days (recovery phase) post injection. Sections from the cerebrum, hindbrain, and cervical, thoracic and lumbar spinal cord were stained as previously described ( J. Neurosci. Res. 29:413, 1991), and scored blindly for histopathological staining. There was minimal histopathological staining at any age in control animals or during the preclinical stage in EAE animals. At the clinical stage of EAE, stained pathological features (macrophages, extravasated RBC and granular staining) were significantly increased compared to the preclinical stage. In the recovery phase, macrophage and granular staining persisted but there was loss of extravasated RBC. Dual labeling studies revealed that granular deposits were present in astrocytes and in locations that appeared to be extracellular. In order to gain insights about the origin of iron deposits in EAE mice, additional studies were performed on brains of mice with extravasated blood lesions. These brains had granular, macrophage and RBC staining. Thus, each of the stained features in EAE animals could be due to the extravasation of blood which occurs in the SJL model of EAE, although some of the iron could have originated from myelin and oligodendrocytes damaged during EAE.
Structure of Saccharomyces cerevisiae α-agglutinin: Evidence for a yeast cell wall protein with multiple immunoglobulin-like domains with atypical disulfides

α-Agglutinin of Saccharomyces cerevisiae is a cell wall-associated protein that mediates cell interaction in mating. Although the mature protein includes about 610 residues, the NH2-terminal half of the protein is sufficient for binding to its ligand a-agglutinin. α-Agglutinin20-351, a fully active fragment of the protein, has been purified and analyzed. Circular dichroism spectroscopy, together with sequence alignments, suggest that α-agglutinin20-351 consists of three immunoglobulin variable-like domains: domain I, residues 20-104; domain II, residues 105-199; and domain III, residues 200-326. Peptide sequencing data established the arrangement of the disulfide bonds in α-agglutinin20-351. Cys97 is disulfide-bonded to Cys114, forming an interdomain bond between domains I and II. Cys202 is bonded to Cys300, in an atypical intradomain disulfide bond between the A and F strands of domain III. Cys227 and Cys256 have free sulfhydryls. Sequencing also showed that at least two of three potential N-glycosylation sites with sequence Asn-Xaa-Thr are glycosylated. At least one of three Asn-Xaa-Ser sequences is not glycosylated. No residues NH2-terminal to Ser282 were O-glycosylated, whereas Ser282, and all hydroxy amino acid residues COOH-terminal to this position were modified. Therefore O-glycosylated Ser and Thr residues cluster in the COOH-terminal region of domain III, and the O-glycosylation continues into a Ser/Thr-rich sequence that extends from domain III to the COOH-terminal of the full-length protein.
Kinetic Modeling of the Propyl Radical β-Scission Reaction: An Application of Composite Energy Methods

In this work, propyl radical β-scission reaction kinetics and energetics were investigated using quantum chemical Gaussian-3 (G3) and complete basis set (CBS) composite energy methods. Experimental thermodynamic and kinetic data were used to assess the accuracy of these calculations. The CBS model proved to have good agreement with the experimental data, which indicates that it is a good method for studying other hydrocarbon cracking reactions involving large species. Furthermore, a kinetic model with pressure and temperature effects was proposed. For P ≤ P0, k = (2.59 × 1011) × P0.40 × e(-13618.16/T); for P > P0, k = (2.70 × 1013) × e(-15117.33/T), where k is the reaction rate constant (in units of s-1), P is the pressure (in units of kPa), T is the temperature (in units of Kelvin), and the switching pressure P0 can be calculated as P0 = (1.53 × 109) × e(-10610.24/T).
The Epidemiology of Uric Acid and Fructose

During the past few decades, the mean serum uric acid levels and the prevalence of hyperuricemia in the general population appear to have increased. Correspondingly, the prevalence and incidence of gout have doubled. Potential reasons behind these trends include the increasing prevalence of obesity and metabolic syndrome, Western lifestyle factors, increased prevalence of medical conditions (eg, renal conditions, hypertension, and cardiovascular disorders), and use of medications that increase uric acid levels (eg, diuretics and low-dose aspirin). The substantial increase in sugar-sweetened soft drinks and associated fructose consumption also has coincided with the secular trend of hyperuricemia and gout. Recently, several large-scale epidemiologic studies have clarified a number of these long-suspected risk factors in relation with hyperuricemia and gout. Furthermore, recent studies have illuminated the substantial comorbidities of hyperuricemia and gout, particularly metabolic-cardiovascular-renal conditions. Although many prospective studies have suggested an independent association between serum uric acid levels and the future risk of cardiovascular-metabolic morbidities and mortality, only a limited number of randomized clinical trials and observational studies recently have shown that the use of allopurinol can be beneficial against these outcomes. Because these data are scarce and the effects of allopurinol might not be limited to decreasing serum uric acid levels, the potential causal role of uric acid on these outcomes remains to be clarified with further studies.
Structural stability in uranium

Diamond-anvil cell experiments and first-principles theory have been used to investigate the structural stability of uranium up to 1 Mbar in pressure. Experiments and theory agree; there is no phase transition in uranium below 1 Mbar. Previous speculations about a crystallographic phase transition in uranium below this pressure are thus shown to be incorrect. In this regard, uranium is exceptional in the series of light actinides, where pressure-induced phase transitions typically occur at pressure below 1 Mbar. The ground-state crystal structure of uranium is orthorhombic with three structural parameters: the axial ratios b/a and c/a, and an internal parameter y measuring the displacement, along the b-axis, of alternate planes. The experimental and theoretical results reported here indicate that one of these parameters, c/a, is substantially more sensitive to pressure than the other two, changing by as much as 5%, while b/a and y are constant within 1% within the pressure range studied. This flexibility in the structure facilitates this structure over a wide pressure range. Theory suggests that electrostatic contributions to the total energy drive the variation in the c/a ratio as a function of pressure, and a simple model is utilized to show this.
Calculation of ground states for many-Ferminon systems☆

Abstract A new method is presented for the exact stochastic solution of the ground states of many-Fermion systems. The antisymmetric ground state wavefunction is expressed as the difference between two positive functions, and the non-linear coupled Schrodinger equation for these functions is solved by a generalized path integral Monte Carlo technique. The method is tested on a two-dimensional example, and its applicability to realistic problems is discussed.
Peripheral axons of the parabolic burster neuron R15

In a combined electrophysiological and anatomical study, the parabolic burster neuron R15 was found to project axons through the genito-pericardial nerve onto the pericardial wall and digestive gland sheath and, more variably, into the heart and pericardial coelom. Projection into these tissues is consistent with the hypothesis that R15 is neurosecretory and may play a role in circulation and/or ion-water regulation in Aplysia.