cssi/SciSciGPT-SciSciNet huggingface dataset:
Finite element method simulation of crack propagation in a brittle microcracking solid

Abstract A finite element method simulation of crack propagation was used to study the effects of microcracking at facets as a damage process in brittle composites and the consequence for material toughness. A continuum model for microcracking at grain boundary facets was used in conjunction with the elasticity law. The model accounts for modulus reduction only and neglects residual strain effects. The nonlinear finite element equations were solved incrementally. The solution for each load increment was obtained using a Newton iteration method. Crack propagation was achieved by successive tip node relaxation upon satisfaction of a critical energy release rate criterion. The crack was allowed to propagate by approximately ten times the height of the initial microcrack zone. A substantial increase of the height of the damage zone prior to steady state propagation was observed. The applied stress intensity factor was increased to sustain crack growth, and crack tip shielding occurs as a result of the wake. The amount of toughening was up to 40% in terms of stress intensity factor and was influenced by the parameters of the constitutive law. Stress, strain, and microcrack density distributions near the tip of the steadily growing crack are discussed.
Enzymatic and immunohistochemical studies on the role of cytochrome P450 and the flavin-containing monooxygenase of mouse skin in the metabolism of pesticides and other xenobiotics

Abstract The cytochrome P450 (P450) content, the cytochrome c reductase activity, the metabolism of a variety of P450 substrates, and the presence and role of flavin-containing monooxygenase (FMO) in xenobiotic metabolism were studied in skin microsomes and compared to those of liver. The cytochrome P450 content of skin as determined by CO-dithionite-reduced minus CO-oxidized spectra was approximately 6.8% of the liver P450 content. By comparison, cytochrome c reductase activity in skin microsomes was high, being equivalent to approximately one-third of the liver microsomal enzyme activity. Skin microsomes metabolized several known P450 substrates and, depending upon the substrate used, the specific activity ranged from 2.5 to 13.4% of the corresponding rates seen in liver microsomes. Skin microsomes exhibited the highest enzymatic activity with benzo[ a ]pyrene and ethoxyresorufin, moderate activity with parathion and aldrin, and low activity with benzphetamine and ethoxycoumarin. Skin microsomes also metabolized the triazine herbicides atrazine, simazine, and terbutryn, with the activity being 2 to 5% of the liver microsomal activity. FMO activity in skin microsomes with thiobenzamide and methimazole as substrates ranged from 10 to 20% of the liver FMO activity. Immunohistochemical studies using antibodies to mouse liver FMO showed localization primarily in the epidermis. Additional studies using pig skin showed a similar distribution pattern. Antibodies developed to mouse liver FMO and the constitutive liver P450 isozyme, 1A2, showed cross-reactivity on Western blots with proteins in skin microsomes that appeared identical to the cross-reacting proteins present in liver microsomes. The relative contribution of P450 and FMO in mouse skin to the sulfoxidation of phorate was investigated and compared to that of liver microsomes. Several procedures were employed to selectively inhibit either P450 or FMO to determine the role of each monooxygenase system in the absence of the other system. In liver microsomes, P450 was responsible for 68 to 85% of the phorate sulfoxidation activity. In contrast, in skin microsomes 66 to 69% of the phorate sulfoxidation activity was due to FMO, while P450 was responsible for the remainder of the activity. Thus, although the overall phorate sulfoxidation rate in mouse skin microsomes was only 3 to 4% of the rate seen in liver, FMO appears to assume a greater relative role to P450 in the metabolic processes in skin.
Injury-related predictors of symptom severity following sports-related concussion

Introduction: Decisions regarding return to play after sports-related concussion partially revolve around athletes’ self-reported symptoms. Given this emphasis on symptoms, it would be beneficial to be able to identify characteristics that could predict which athletes may be susceptible to developing an increase in postconcussion symptoms following head injury. The purpose of this study was to describe the symptoms that athletes endorse immediately following concussion and to determine what impact injury-related characteristics have on the development of postconcussion symptoms within the first week following concussion. Method: Participants included 54 collegiate athletes who sustained concussions and were referred to our concussion management program for postconcussion testing. The main outcome measures included the Post-Concussion Symptom Scale and an interview querying athletes’ retrospective symptoms over time, starting immediately postinjury. Results: Descriptive statistics revealed that the most co...
Physiological responses of fresh-cut apple slices under high CO2 and low O2 partial pressures

Abstract The physiological responses of ‘Delicious’ apple slices to 0–30 kPa CO2 at 0–10 kPa O2 partial pressures at 5°C have been studied. Increasing CO2 partial pressures from 0 to 30 kPa at 0.5, 1 and 10 kPa O2 reduced respiration rates and ethylene production of the slices. The inhibitory effect of CO2 on respiration rate of slices was best explained by an enzyme kinetics model that combined competitive and uncompetitive types of inhibition. Browning increased during storage and was reduced by CO2 to only a limited extent. CO2 levels of 15–30 kPa resulted in about a 50% reduction in acetaldehyde, ethanol and ethyl acetate concentrations in tissues under both anaerobic and low-O2 atmospheres compared with slices kept in CO2-free atmospheres. Elevated CO2 might provide a mechanism to reduce accumulation of fermentation products but sensory quality of slices needs be studied before recommending its use.
The reaction of perfluorobicyclic ethers and perfluorospiro-ethers with anhydrous aluminum chloride

Abstract Perfluorobicyclic ethers and perfluorospiroethers, all containing an oxolane skeleton, were treated with AlCl 3 in a heterogeneous manner to give the corresponding α,α,α′-trichlorinated and α,α-dichlorinated products, respectively. From perfluoroacetal compounds, for example, perfluoro(8-methoxy-7-oxabicyclo- [4.3.0]nonane), mono- and di-chlorinated products, i.e. perfluoro- (8-chloro-8-methoxy-7-oxabicyclo[4.3.0]nonane) and perfluoro- (8,8-dichloro-7-oxabicyclo[4.3.0]nonane) were obtained in good yields. The action of fuming sulfuric acid on these polychlorinated products led to the formation of the corresponding lactones. Perfluoro(6-chloro-7-oxa-8-oxobicyclo[4.3.0]nonane) was treated with (CH 3 ) 2 NLi to give N,N-dimethylundecafluoro-2-oxocyclohexyl- acetamide.
High-throughput yeast plasmid overexpression screen.

The budding yeast, Saccharomyces cerevisiae, is a powerful model system for defining fundamental mechanisms of many important cellular processes, including those with direct relevance to human disease. Because of its short generation time and well-characterized genome, a major experimental advantage of the yeast model system is the ability to perform genetic screens to identify genes and pathways that are involved in a given process. Over the last thirty years such genetic screens have been used to elucidate the cell cycle, secretory pathway, and many more highly conserved aspects of eukaryotic cell biology 1-5. In the last few years, several genomewide libraries of yeast strains and plasmids have been generated 6-10. These collections now allow for the systematic interrogation of gene function using gain- and loss-of-function approaches 11-16. Here we provide a detailed protocol for the use of a high-throughput yeast transformation protocol with a liquid handling robot to perform a plasmid overexpression screen, using an arrayed library of 5,500 yeast plasmids. We have been using these screens to identify genetic modifiers of toxicity associated with the accumulation of aggregation-prone human neurodegenerative disease proteins. The methods presented here are readily adaptable to the study of other cellular phenotypes of interest.
Asset specificity and economic organization

Abstract This paper examines the optimization problem of firm and market organization in which both production cost and transaction cost differences are expressed as a function of asset specificity. In general, markets enjoy advantages by aggregating the demands of many buyers, thereby realizing economies of scale or scope. Such production cost savings need to be assessed in relation to the transaction cost advantages that internal organization sometimes enjoys over markets in adapting to changed circumstances. As it turns out, both production cost economies and the transaction cost differences between firm and market organization vary systematically with the characteristics of the investments. This paper employs a unified framework to assess the choice of organization form. The condition of asset specificity is featured.
The incidence and clinical significance of ECG-VCG changes of myocardial infarction following aortocoronary saphenous vein bypass surgery.

Abstract The electrocardiogram and vectorcardiogram were analyzed in 35 consecutive patients before and after undergoing elective aortocoronary saphenous vein bypass grafting for angina pectoris. Typical changes of perioperative myocardial infarction were seen in 40 per cent (ECG) and 46 per cent (VCG). Changes of ST segments and T wave could not be correlated with QRS changes of infarction. Surgery with or without infarction resulted in a loss in R wave voltage in anterior and lateral precordial leads (V 4 , V 5 , and V 6 ) as well as in a symmetric shrinkage of the vector loop in the transverse and frontal planes. Comparing one year follow-up results of those with versus those without perioperative VCG changes of infarction showed that late death, clinical evidence of myocardial damage, and reinfarction were more frequent in the infarction group. However, no difference in N.Y.H.A. functional classification, congestive heart failure alone, or persistence of angina pectoris could be demonstrated between the two groups. The ECG and VCG changes of perioperative infarction are common with this operation and helped to predict late morbidity and death.
Teacher salaries and student achievement: the case of Pennsylvania

In this article, we developed an empirical model and tested the hypothesis that teacher salaries and student achievement are positively and significantly related. A total of 500 school districts in the state of Pennsylvania for 3 school years (1999–2000, 2000–2001 and 2001–2002) were selected for a case study. Consequently, the empirical evidence revealed that the hypothesis was accepted, implying that higher teacher salaries attract better qualified teachers and thus benefits student learning and improves student achievement.
Elevated salivary endothelin levels in oral cancer patients—A pilot study

The analysis of saliva has been proposed as a potentially rapid, non-invasive method to monitor and diagnose patients with oral disease. In this study we measured salivary endothelin-1 (ET-1) levels in patients diagnosed with oral squamous cell carcinoma (SCC) prior to treatment. We demonstrate significantly elevated salivary ET-1 levels in the oral SCC group (4.37+/-1.35pg/ml), relative to the control group (1.16+/-0.29pg/ml). ET-1 and ET-1 mRNA were also measured in oral SCC tissue specimens and compared to normal oral epithelial controls. The concentration of ET-1 in the oral SCC specimens was 17.87+/-4.0pg/ml and in the normal epithelial controls the concentration of ET-1 was 5.43+/-2.5pg/ml. ET-1 mRNA was significantly overexpressed in 80% (8/10) of the oral SCC specimens. Our results demonstrate the potential utility of salivary analysis for ET-1 levels to monitor patients at risk for oral SCC.
Long-term outcome of pediatric obsessive-compulsive disorder: a meta-analysis and qualitative review of the literature.

Objective: To review the extant literature on the long-term outcome of child/adolescent-onset obsessive–compulsive disorder (OCD). Method: Medline and Psychlit databases were systematically searched for articles regarding long-term outcomes of child/adolescent-onset OCD. Meta-analysis regression was applied to evaluate predictors and persistence of OCD. Results: Sixteen study samples (n = 6–132; total = 521 participants) in 22 studies had follow-up periods ranging between 1 and 15.6 years. Pooled mean persistence rates were 41% for full OCD and 60% for full or subthreshold OCD. Earlier age of OCD onset (z = −3.26, P = 0.001), increased OCD duration (z = 2.22, P = 0.027) and in-patient vs. out-patient status (z = 2.94, P = 0.003) predicted greater persistence. Comorbid psychiatric illness and poor initial treatment response were poor prognostic factors. Although psychosocial function was frequently compromised, most studies lacked comprehensive outcome measures. Conclusion: Long-term persistence of pediatric OCD may be lower than believed. Future studies should include broader measures of outcome including symptomatic persistence and functional impairment in multiple domains.
Design considerations for multilayer-coated Schwarzchild objectives for the XUV

ABSTRACT The performance of multilayer—coated Schwarzschild objectives, and similar nearnormal incidence soft xray focussing systems, can be affected by the changing anglesof incidence for different rays and possible variations in multilayer period acrossthe curved mirror surfaces. A design analysis which considers these issues ispresented, using as an example a 20 times demagnifying Schwarzschild objective coatedwith molybdenum/silicon multilayers for operation at roughly 76 eV. The largebandwidth of these multi].ayers eases requirements on control of the variation of thed—epacing for the system considered. Implications for extension to similar systemsoperating with different magnifications, sizes, and photon energies are discussed. 1. INTRODUCTION The advent of multilayer reflective coatings for extreme ultraviolet to x—ray (XUV)wavelengths in the last decade has extended the spectral range of significant near—normal incidence reflectance into these regions. Especially exciting among the manyapplications made possible by these nanometer—scale interference structures are thosein which multilayers are applied to curved optics for focussing. Such applicationsinclude, for example, experiments utilizing a single curved multilayer mirror forimaging1'2'3 and for gain enhancement in multipass x—ray laser experiments.4'5Compound multilayer-coated focusing optics, such as Schwarzschild objectives, arebeginning to be utilized in microscopy6'7'8'9 and astronomy, and these and similaroptics are being investigated for use in soft x-ray projection lithography.10'11'12It is this later class of compound multilayer-coated, near—normal incidence opticsthat are the subject of this paper.This paper investigates issues relating the areal distribution of multilayer periodon the curved surfaces of compound reflective optics to the performance of theseoptics. We present an analysis combining the geometrical optical considerations ofSchwarzschild objectives with the physical optical considerations relating tomultilayer reflective structures and the deposition system dependent considerationswhich affect the variation of multilayer period on curved surfaces. Discussion isbased on experience gained in the course of the design and coating of severaldifferent Schwarzschild objectives (SO) for soft x-ray magnifying and demagnifyingapplications. To illustrate the analysis we examine a 20X reduction system whichdemagnifies a beam from an undulator source at the Synchrotron Radiation Center(University of Wisconsin, Madison) to form a sub—micron spot primarily for use inphotoelectron spectro—microscopy studies of various surfaces. Some details thisproject, called MAXIMUM, can be found in ref. 8.
The operation was a success but the patient died: A critique of “the implementation and evaluation of a problem-solving training program for adolescents”

Abstract This critique examines George S. Tellado's account of his evaluation of a problem-solving program for adolescents in a public junior high school in Pennsylvania. The program was apparently successful (i.e., it was shown by the evaluation to improve students' problem-solving capacities), and the evaluation was, for the most part, technically sound, but the program did not survive. This critique suggests that by examining the problem-solving program as an organizational change intervention, several problems can be uncovered regarding the program's design, implementation, evaluation, and institutionalization. In particular, it appears that the school system's staff did not have sufficient ownership of the program to understand it or to wish to carry it on after the program's originator and evaluator were no longer present. This article addresses these problems in detail and recommends techniques from the field of organizational change consultation to increase the likelihood that such programs will live on into the future.
Storage and Moisture Effects on Peanut Composition and Roasted Flavor1

Abstract Shelled, raw peanuts were placed in storage approximating commercial conditions at 6.2–6.3% and 8.7–9.2% moisture contents during a two year period. The 1978 storage period was from December, 1978 through August, 1979. The 1979 period was from October, 1979 through March, 1980. The moisture condition 8.7% for 1978 and 9.2% for 1979 showed significant differences in free amino acids and free sugars when compared to the 6% treatment. This suggests that 9% moisture content allows increased hydrolysis of complex constituents and significant deterioration of quality to occur. Peanuts with 9% moisture contents produced darker peanut butter with reduced flavor quality than those with 6%. Hunter reflectance values indicated that the skins of raw peanuts with higher moisture content were also darker. Evaluation of the lipid fractions suggested that only the phospholipid fraction from the 9% moisture treatment was significantly changed. Since phospholipids are primarily associated with the membrance portio...
THE "GREAT GAME": MONGOLIA BETWEEN RUSSIA AND CHINA

No abstract available. DOI: http://dx.doi.org/10.5564/mjia.v4i0.421 Mongolian Journal of International Affairs Vol.4 2007: 62-71
Whither the Decline

In the fall of 1969 we arrived in St. Louis, ready to begin our freshman year at Washington University. Over the course of the next four years there we experi enced Kent State, the student revolution, the search for meaning, the search for identity, and the search for a future. It was at Washington University that we discovered and fell in love with each other and with sociology, making a lifetime commitment to both. By the time we graduated in the spring of 1973, we had formed a cohesive community of close friends, and a solid base for our future sociological careers. In the fall of 1986 we returned to St. Louis, this time as visiting professors in the department where we had been undergraduates thirteen years earlier. We spent a productive year there and were tempted to settle in St. Louis permanently (we were offered two tenure-track jobs), but ultimately moved on at the end of the year because the department's future prospects were so uncertain. Its dissolution was announced shortly after we left. In thinking about and analyzing the meaning and significance of the depart ment's closure, we will attempt to draw upon the two periods of time that we were there, the two diverse roles that we occupied, and the distinct perspectives encompassed within those roles. As undergraduates, we knew little of either the politics or reputation of the department. We were thus unaware of the department's international prominence and of the internal battles that had fragmented it only the year before, sending many of its leading faculty members fleeing to other schools. Alvin Gouldner, one of the remaining scholars, was in Amsterdam, leaving only the conspicuous sign,
Temporal trends in algae, benthic invertebrate, and fish assemblages in streams and rivers draining basins of varying land use in the south-central United States, 1993–2007

Site-specific temporal trends in algae, benthic invertebrate, and fish assemblages were investigated in 15 streams and rivers draining basins of varying land use in the south-central United States from 1993–2007. A multivariate approach was used to identify sites with statistically significant trends in aquatic assemblages which were then tested for correlations with assemblage metrics and abiotic environmental variables (climate, water quality, streamflow, and physical habitat). Significant temporal trends in one or more of the aquatic assemblages were identified at more than half (eight of 15) of the streams in the study. Assemblage metrics and abiotic environmental variables found to be significantly correlated with aquatic assemblages differed between land use categories. For example, algal assemblages at undeveloped sites were associated with physical habitat, while algal assemblages at more anthropogenically altered sites (agricultural and urban) were associated with nutrient and streamflow metrics. In urban stream sites results indicate that streamflow metrics may act as important controls on water quality conditions, as represented by aquatic assemblage metrics. The site-specific identification of biotic trends and abiotic–biotic relations presented here will provide valuable information that can inform interpretation of continued monitoring data and the design of future studies. In addition, the subsets of abiotic variables identified as potentially important drivers of change in aquatic assemblages provide policy makers and resource managers with information that will assist in the design and implementation of monitoring programs aimed at the protection of aquatic resources.
Two-dimensional model of distributed charge transfer and internal reforming within unit cells of segmented-in-series solid-oxide fuel cells

This paper develops a computational model to represent details of reactive porous-media transport, elementary catalytic chemistry, and electrochemistry within unit cells of segmented-in-series solid oxide fuel cell (SIS-SOFC) modules. Because the composite electrode structures are thin (order of tens of microns), electrochemical charge-transfer chemistry can proceed throughout the composite electrode structures. Modeling such spatially distributed charge transfer is significantly more complex than modeling situations where the charge transfer can be represented at an interface between electrode and electrolyte. The present model predicts electric-potential fields of electrode and electrolyte phases, with the charge-transfer rates depending upon local electric-potential differences and the local gas-phase composition. The paper summarizes the underpinning physical and chemical models and uses examples to illustrate and interpret important aspects of SIS performance.
Conducted energy devices and criminal justice policy

Samuel Walker’s (1993) book, Taming the system: The control of discretion in criminal justice, 1950–1990, provides time-tested insights on the relationship between bureaucratic decision making and criminal justice policy. Published in the early 1990s, the book provides an analysis of existing literature that pertains to the exercise of discretion at specific criminal justice decision points. Walker discussed that often both anticipated and unanticipated consequences develop after new policy changes are implemented—a conclusion that is consistent with many other classic and contemporary work that points to the instabilities of policy reform. Legislatures, bureaucratic organizations, and courts often initiate policy change to control discretion, and sometimes these efforts are successful. For example, Walker (1993: 147) referred to the control of deadly force in policing as having “enormous significance,” and that the adopted rules reduced the overall number of police shootings and helped minimize racial disparities in the use of deadly force. These changes, in addition, had few unanticipated consequences because officers killed or injured in the line of duty did not increase after the adoption of new deadly force policies. New policies can, thus, positively initiate change in criminal justice organizations, and documenting the “law on the books” provides a good starting point for understanding better the impacts of policy change. Such changes, however, also can result in a bureaucratic chain reaction that subverts, undermines, or delegitimizes the intent of the new rule or decision. Personnel will attempt to break or bend any new rule so that the impact is consistent with their accepted and expected routines. The conflict between “law on the books” and “law in action” provides one element of the policy context for the important debate engaged in this section of the journal. The use of conducted energy devices (CEDs), the most popular of which is the TASER (Taser International, Inc., Scottsdale, AZ), is widespread within the law-enforcement community—nearly 12,000 lawenforcement agencies have acquired the devices (National Institute of Justice [NIJ], 2008). It could be argued that the adoption of such devices (and other less lethal weapons) is a sensible policy change that was adopted to manage better one of law enforcement’s most volatile
Association between DNA cleavage during apoptosis and regions of chromatin replication

We have addressed the association between the site of DNA cleavage during apoptosis and DNA replication. DNA double strand breaks were introduced into chromatin containing pulse labeled nascent DNA by the induction of apoptosis or autocleavage of isolated nuclei. The location of these breaks in relation to nascent DNA were revealed by Bal 31 exonuclease digestion at the cut sites. Our data show that Bal31 accessible cut sites are directly linked to regions enriched in nascent DNA. We suggest that these regions coincide with the termini of replication domains, possibly linked by strong DNA-matrix interactions with biophysically defined topological structures of 0.5 - 1.3 Mbp in size. The 50 kbp fragments that are commonly observed as products of apoptosis are also enriched in nascent DNA within internal regions but not at their termini. It is proposed that these fragments contain a subset of replicon DNA that is excised during apoptosis through recognition of their weak attachment to the nuclear matrix within the replication domain.J. Cell. Biochem. 70:604-615, 1998. © 1998 Wiley-Liss, Inc. © 1998 Wiley-Liss, Inc.
Isolated plantar midtarsal dislocation

A case of isolated plantar midtarsal dislocation resulting from blunt trauma is presented. Review of the English-language literature reveals this to be an extremely rare injury. Strategies for emergency department management of this injury are discussed.
In vitro and in vivo X‐irradiation of preimplantation mouse embryos

Two-day-old strain 129/SvSl mouse embryos obtained by induced superovulation were exposed to various doses of X-rays in vitro and in vivo and cultured from the 4-cell to the blastocyst stage. The LD50 for blastocyst development 48 h after in vitro irradiation was 300 R and following in vivo irradiation was 600 R. Blastulation occurred in over 80% of the cultured sham-irradiated control embryos. Treated and control embryos that blastulated after 48 h of culture were transplanted to nulliparous adult 2-day pseudo-pregnant 129/SvSl females and examined 15 days later. Approximately 70% of implanting control blastocysts developed into fetuses. Significantly fewer fetuses developed after in vitro exposure to more than 73 R. No fetal development occurred following in vitro irradiation with more than 170 R. No indication of implantation was observed for embryos irradiated in vitro with more than 267 R. Fetal development occurred following in vivo irradiation with 388 R. It appears that it required twice as much in vivo irradiation as in vitro irradiation to produce equivalent lethality for the early mouse embryo. No significant gross abnormalities were observed in preterm fetuses following embryonic irradiation in vitro or in vivo, but there was significant weight-gain impairment in fetuses developing from transplanted embryos irradiated in vitro with 73 R or more.
Predictors of Sexual Functioning in a Sample of U.S. Marines: An 11-Year Follow-Up Study

ABSTRACT We examined predictors of sexual functioning in male and female U.S. Marines (n = 589) assessed longitudinally for approximately 11 years. Multiple domains of sexual functioning (dysfunctional sexual behaviors, sexual frequency, sexual problems, and sexual satisfaction) were assessed at the 11-year follow-up assessment (T5). T5 depressive symptoms emerged as the most robust predictor of all domains of sexual functioning. Different patterns of correlates were associated with the different domains of sexual functioning—a finding that highlights the importance of considering the multidimensional nature of human sexuality. In addition, several significant gender × predictor interactions indicated differential relationships between predictors and sexual functioning outcomes for men and women. In particular, concurrent physical health and mental health were more strongly related to sexual functioning for women compared with men. We discuss how findings of the current study can contribute to the develop...
Primary mediastinal choriocarcinoma in the male.

The case of a 28-year-old man with primary mediastinal choriocarcinoma is reported. It represents the first instance in which a partial remission and augmented survival were achieved in treating this neoplasm, previously shown to be completely refractory to all forms of antitumor therapy. Combination chemotherapy, as employed in the present case, holds promise of even more substantial results, especially if the diagnosis can be made earlier in the course of the disease. Diagnostic and therapeutic modalities currently available are discussed, with particular emphasis on the need for speedy workup and early treatment of this rapidly fatal illness.
Emerging and disappearing synergies in a hierarchically controlled system

The purpose of the study was to explore the ability of the central nervous system (CNS) to organize synergies at two levels of a hypothetical control hierarchy involved in two-hand, multi-finger tasks. We investigated indices (ΔV) of finger force co-variation across trials as reflections of synergies stabilizing the total force (FTOT). Subjects produced constant force with one or two finger-pairs (from one hand or two hands). In trials starting with one finger-pair, subjects added another finger-pair without changing FTOT. In trials starting with two finger-pairs, subjects removed one of the finger-pairs without changing FTOT. Adding or removing a finger-pair resulted in a transient drop in ΔV computed for the finger-pair that remained active throughout the trial. This drop in ΔV was seen simultaneously with force changes. Compared to the original steady-state, addition of a finger-pair led to a significant drop in ΔV at the newly established steady-state. This drop eliminated negative co-variation among finger forces that had stabilized FTOT. In contrast, in trials starting with two finger-pairs, no negative co-variation between finger forces within-a-pair was seen. Removing a finger-pair led to the emergence of negative co-variation between finger forces at the new steady-state. The ΔV index computed across two finger-pairs confirmed the existence of negative force co-variation. The emergence and disappearance of force stabilizing synergies within a finger-pair may signal limitations in the ability of the CNS in forming synergies at two different hierarchical levels.
Effect of physical state (solid vs. liquid) of lipid core on the rate of transport of oxygen and free radicals in solid lipid nanoparticles and emulsion

Solid lipid nanoparticles (SLNs) may have significant potential to limit oxidation of encapsulated bioactive compounds. This is based on the hypothesis that the solid core in SLNs can significantly limit the rate of transport of oxygen and free radicals into the lipid core from the aqueous phase. In this study, we have directly compared the rate of transport of oxygen and free radicals in SLNs and liquid emulsion prepared from the same lipid material (eicosane) at a fixed temperature. Eicosane nanoparticles stabilized by high melting lecithin and bile salts were used as a model system. The physical state (solid vs. liquid) of the lipid phase was engineered using the supercooling phenomenon of emulsified eicosane. Transport of oxygen and free radicals was measured based on changes in fluorescence intensity of oxygen or peroxyl radical sensitive dyes encapsulated in the lipid phase upon exposure to either air or peroxyl radicals generated in the aqueous phase. The results showed that the rate of oxygen transport was marginally reduced in SLNs as compared to liquid emulsion, while the rate of transport of peroxyl free radicals was not significantly affected by the physical state of the lipid core in SLNs and emulsion. Together, these results indicated that the solid core of SLNs does not significantly reduce the rate of transport of oxygen or free radicals as compared to the liquid core emulsion. To address this paradox, the distribution of encapsulated dye was characterized in both SLNs and emulsion using fluorescence imaging. The results showed significant redistribution of the encapsulated dye molecules with formation of the solid lipid core. In contrast to homogeneous distribution in the liquid emulsion, SLNs showed higher concentration of the dye at the periphery as compared to the center of the lipid droplet. The expulsion of encapsulated molecules to the surface of SLNs can potentially limit the ability of the solid core to protect encapsulated products from oxygen and free radicals.
Solvation energies of planar and pseudo-planar molecules

The Born equation for solute-solvent interaction is generalized to planar and pseudo-planar molecules. The solvation energies thus obtained are compared to experimental values and the agreement is satisfactory.
Impacts of urbanization on groundwater quality and recharge in a semi-arid alluvial basin

Summary The management of groundwater resources is paramount in semi-arid regions experiencing urban development. In the southwestern United States, enhancing recharge of urban storm runoff has been identified as a strategy for augmenting groundwater resources. An understanding of how urbanization may impact the timing of groundwater recharge and its quality is a prerequisite for mitigating water scarcity and identifying vulnerability to contamination. We sampled groundwater wells along the Rillito Creek in southern Arizona that had been previously analyzed for tritium in the late 1980s to early 1990s and analyzed samples for tritium (3H) and helium-3 (3H/3He) to evaluate changes in 3H and age date groundwaters. Groundwater samples were also analyzed for chlorofluorocarbons (CFCs) and basic water quality metrics. Substantial changes in 3H values from waters sampled in the early 1990s compared to 2009 were identified after accounting for radioactive decay and indicate areas of rapid recharge. 3H–3He groundwater ages ranged from 22 years before 2009 to modern recharge. CFC-11, -12 and -113 concentrations were anomalously high across the basin, and non-point source pollution in runoff and/or leaky infrastructure was identified as the most plausible source of this contamination. CFCs were strongly and positively correlated to nitrate (r2 = 0.77) and a mobile trace metal, nickel (r2 = 0.71), suggesting that solutes were derived from a similar source. Findings from this study suggest new waters from urban non-point sources are contributing to groundwater recharge and adversely affecting water quality. Reducing delivery of contaminants to areas of focused recharge will be critical to protect future groundwater resources.
On a Nonlinear Differential Equation of Electrohydrodynamics

A nonlinear differential equation which governs the equilibrium of two closely spaced drops, suspended from two circular rings, and maintained at electric potentials ± V is considered. When the potential reaches a critical value V m , experiments show that the drops coalesce and the equation has, in fact, no solutions for V > V m . Two limiting cases are studied. At first we consider drops which at zero potential difference, are films of zero curvature. In this case it is shown that the equation may not have a unique solution for V m . In the second case we study drops which are nearly touching when there is no potential difference, with non-zero curvature. Using the method of matched asymptotic expansions, it is shown that when the drops are about to coalesce, the original separation distance is reduced by one-half. Thus the drops are not drawn out as might have been expected from experiments on isolated drops.
Systems Level Performance Estimations for a Pulse Detonation Combustor Based Hybrid Engine

The Pulse Detonation Combustor (PDC) has recently evoked much interest as a pressure-gain combustor for use in gas turbines. A key application for a Pulse Detonation Engine (PDE) concept has been envisioned as a hybrid power generation engine, which would replace the combustor in a conventional gas turbine with a PDC. Estimations of performance parameters, namely, thermal efficiency (ηth ) and specific work (Wnet ) are reported for a PDC based hybrid engine for various configurations of the engine. The performance enhancing configurations of the PDC-based hybrid engine, considered in the present study, include simple cycle, intercooling, regeneration and reheat, similar to the configurations for a conventional gas turbine (GT) engine in the literature. The performance estimations for a conventional gas turbine engine and a PDC based hybrid engine are compared for the same operating conditions (such as inlet pressure, inlet temperature, compression ratio, overall equivalence ratio) and for various configurations. The thermal efficiency of an intercooled PDC hybrid engine with regeneration has the highest value for the entire range of turbine pressure ratios, from 1.2 to 40 (corresponding to a compression ratio range of 1 to 30). An intercooled PDC based hybrid engine with reheat produces the highest specific work (Wnet ) when compared to all other configurations. Among simple-cycle /regeneration /reheat configurations of a PDC based hybrid engine, ητh for the intercooled PDC based hybrid engines has the highest estimated value (0.47) at a turbine pressure ratio of 30. The intercooled PDC based hybrid engine also produces the highest specific work (Wnet ) when compared to simple-cycle/regeneration/reheat hybrid engine configurations over the entire range of turbine pressure ratios.Copyright © 2008 by ASME
A postulational approach to the problem of ion flux through membranes

Abstract It is shown that the independent linear flux of an ion species though a symmetrical Nernstian membrane that is ohmic near zero potential can be described completely except for a constant permeability and an unknown function of membrane voltage that is even and has value unity at the origin. An attractive feature of this approach is that the underlying assumptions admit of direct, though not necessarily easy, experimental verification. Extensions are given that (i) produce the principal results of a constant field approach without making any assumptions about microscopic processes within the membrane, and (ii) explain qualitatively the effects of tetraethylammonium ions on squid axon.
EXERCISE AS TREATMENT FOR OBESITY

As many as 40% of women and 24% of men are trying to lose weight at any given time. 70 Exercise has been used as a unique mode of treatment for obesity. Most often, it has been included as part of weight-reducing programs which include dietary restriction and behavior modification. Because a large number of people are overweight, and because that number is growing, 53 there is an absolute need to develop effective treatment or preventive approaches for obesity so that the negative health consequences associated with this condition can be eliminated. This article reviews the efficacy of using exercise as a practical treatment for obesity. Obesity can be defined as the excessive accumulation of body fat. In the literature, frequent reference is made to moderate and severe obesity. In this article, moderate obesity is defined as a body mass index (BMI), calculated as weight in kilograms divided by height in meters squared, of between 27 and 31 and severe obesity as a BMI of greater than 31. Similar criteria were used by Atkinson and Walberg-Rankin 6 in their recent review. Exercise or physical activity is defined as any rhythmical activity which elevates heart rate above resting levels and involves the use of a large muscle group or the coordinated use of several large muscle groups. Examples of such exercise include walking/jogging, cycling, aerobic dance, rowing, stair climbing, skating (ice, roller, and roller blade), and weight lifting. Participation in sport activities such as volleyball, basketball, softball, and soccer is also defined as exercise. The overall hypothesis is that regular exercise elevates total daily energy expenditure (TDEE) and that as long as this increase in energy expenditure is not offset by an increase in energy intake, weight loss or weight maintenance following a period of weight loss will be achieved. Reasons for the recent surge in the prevalence of obesity are not completely understood. The increased incidence is most likely not the result of a shift in the genetic milieu of most affluent societies making them more susceptible to becoming overfat but rather a reflection of how the current environment interacts with a genetic background. Lifestyles have changed in recent years such that physical activity is reduced, food is abundant and readily available, consumption of fruits and vegetables is decreased, and sugar and fat intake is increased. Most likely, these changes in habitual daily living have resulted in an increasing number of overweight individuals. Much of the literature reviewed in this paper describes the effects of a formal exercise program on reversal or prevention of obesity. Physical activity is no longer a part of our daily routines, and, as such, we are forced to find time to implement a formal program of exercise. This makes exercise a chore, less interesting, and therefore more likely to be cut out of our daily routines. This poses an intriguing question: in our current lifestyle, do we need formal exercise programs or do we need to be less inactive?
Induction and catalytic properties of an intracellular NADH-dependent 1,4-benzoquinone reductase from the brown-rot basidiomycete Gloeophyllum trabeum

Abstract The expression of intracellular NADH-dependent 1,4-benzoquinone reductase in the brown-rot fungus Gloeophyllum trabeum was increased in the presence of 2,6-dimethoxy-1,4-benzoquinone (2,6-DMBQ) and, to a lesser extent, vanillic acid. Expression was time-dependent and influenced by nitrogen levels. An intracellular NADH-dependent 1,4-benzoquinone reductase was purified from G. trabeum . The subunit molecular mass was 22 kDa . Flavin mononucleotide was the coenzyme. The pI of the enzyme was 4.2. The quinone reductase catalyzed the reduction of multiple 1,4-quinones and exhibited Ping–Pong kinetics. For enzyme-catalyzed 2,6-DMBQ reduction, the apparent K M was 6.8 μM and the k cat 1.0×10 3 s −1 ; the pH optimum was between 5.5 and 7; the activation energy of the reaction was estimated at 43.7 kJ mol −1 . The one-to-one stoichiometric ratio of NADH oxidation versus 2,6-DMBQ reduction suggested a two-electron transfer mechanism for the enzyme. Dicumarol and Cibacron blue were competitive inhibitors with K i values of 0.5 and 0.2 μM , respectively.
The effect of surface applied soil amendments on barley root growth in an acid subsoil

Abstract The root growth of an Al sensitive barley (Hordeum vulgare L.) was used to evaluate the influence of surface applied amendments on the properties of an acid subsoil. Soil columns were packed with 10 cm of A horizon over 45 cm of an acidic Bt horizon from a Gilpin silt loam. Prior to planting of the barley the columns received surface treatments of dolomitic lime (8.4 Mg.ha‐1), hog manure (44.8 Mg.ha‐1) with and without lime, cow manure (44.8 Mg.ha‐1) with and without lime, gypsum (14.6 Mg.ha‐1), and EDTA (5.1 Mg.ha‐1) with lime. The columns were leached twice weekly over a 6 week period with 5 cm additions of water. Lime alone did not significantly increase subsoil pH or reduce exchangeable Al at depths below 15 cm. The EDTA plus lime treatment caused significant increases in soil pH and reductions in exchangeable Al throughout the column. Gypsum treatments also reduced exchangeable Al but neither gypsum nor EDTA plus lime treatments resulted in Improved barley root growth or rooting depth in the...
Atmospheric and surface cloud radiative forcing: results from climate models

Cloud radiative forcing (CRF) is the difference between the radiative flux (at the top of the atmosphere, say) which actually occurs in the presence of clouds, and that which would occur if the clouds were removed but the atmospheric state were otherwise unchanged1'2. We also use the term CRF to denote warming or cooling tendencies due to cloud-radiation interactions. Cloud feedback is the change in CRF that accompanies a climate change. It is useful to distinguish among three aspects of the CRF: the "planetary CRF" acting at the top of the atmosphere, the "surface CRF" at the Earth's surface, and the "atmospheric CRF," which acts on the atmosphere itself and is the difference between the planetary and surface CRFs. The planetary CRF, which can be observed from satellites, can be thought of as the sum of the surface CRF and the atmospheric CRF. Because clouds do not absorb much solar radiation, the atmospheric CRF (hereafter, ACRF) is almost entirely due to interactions of the clouds with infrared radiation. The surface CRF involves important contributions from both solar and infrared radiation. Its solar component is strongly correlated with the solar portion of the planetary CRY, and so may be relatively easy to infer from space observations. The infrared surface CRF is much more difficult to observe. This paper presents climate model results concerning the magnitudes, distribution, causes, and consequences of the atmospheric and surface CRF. A review of some earlier studies is combined with a brief presentation of new, previously unpublished results.
All in the family: utilizing shared resources across campuses

Utilizing available resources in a University environment is a challenging venture. Technology support professionals are constantly faced with too little time and money and too much demand for those resources. This paper will describe how the campuses of Louisiana State University (LSU) and Louisiana State University's Pennington Biomedical Research Center (PBRC) came together to share resources in order to efficiently meet demand from the customers they served as well as support and train their own technology analysts. The shared resources accomplished by this collaboration were: 1.Licensing:With master licensing contracts negotiated by Louisiana State University, the Pennington Campus was able to save time and money. Support managers are able to compare vendors and benchmark costs. 2.Students:Support managers share procedures for hiring, promoting, and terminating new students as well as evaluation and motivational tactics.Student resumes are shared based on job description and position availability. 3.Training:Managers from the satellite campus attend training at LSU's main campus to observe and gather materials to use for training at PBRC's campus.PBRC's campus is without a training facility; therefore, the student workers are trained through the START program on LSU's campus. 4.Applications:Researching new technology such as NetMeeting, VMWare, Wireless devices. Troubleshooting existing technology shared between the two campuses.