cssi/SciSciGPT-SciSciNet huggingface dataset:
Modeling FES Actuation and Control of Multisegment Limb Movements

Functional Electrical Stimulation (FES) has been demonstrated as a promising technique for restoring motor function to otherwise paralyzed limbs. Though much progress remains in the technological arena to improve stimulation delivery systems, similar efforts must be directed to the equally-important problem of coordinating the complex, dynamically-coupled system of interconnected body segments. In present clinical studies, open-loop muscle stimulation (i.e. control) patterns are typically prescribed via a painstaking trial-and-error process. If FES is ever to become a viable means of restoring upright ambulation, hand function, and the like, our ability to control the simultaneous motions of many segments will be crucial. Through dynamic musculoskeletal modeling, we have the opportunity to study the coordination problem without the constraints imposed by present limitations in stimulation technology. Our modeling studies have focused upon: (a) the development of improved musculotendon actuator and joint models, (b) characterizing the complex system of interconnected body segments and the effects of muscle contractions on body-segment accelerations, and (c) developing techniques for controlling electrically-stimulated limb movements.
Profiling risk and sustainability in coastal deltas of the world

Deltas are highly sensitive to increasing risks arising from local human activities, land subsidence, regional water management, global sea-level rise, and climate extremes. We quantified changing flood risk due to extreme events using an integrated set of global environmental, geophysical, and social indicators. Although risks are distributed across all levels of economic development, wealthy countries effectively limit their present-day threat by gross domestic product–enabled infrastructure and coastal defense investments. In an energy-constrained future, such protections will probably prove to be unsustainable, raising relative risks by four to eight times in the Mississippi and Rhine deltas and by one-and-a-half to four times in the Chao Phraya and Yangtze deltas. The current emphasis on short-term solutions for the world’s deltas will greatly constrain options for designing sustainable solutions in the long term.
Redistribution of strain and curvature in the porcine anterior lens capsule following a continuous circular capsulorhexis

Cataract surgery is the most commonly performed surgical procedure in the US, it consists of three steps: introduction of a hole into the lens capsule, removal of the clouded lens through this access hole, and insertion of an artificial lens. We hypothesize that errant behavior by the residual epithelial cells of the lens capsule following surgery are due, in part, to surgically-induced changes of the native stress and strain fields in the lens capsule. Because the capsular bag can be regarded mechanically as a membrane, here we study changes in curvature and strains due to the most common means of introducing the initial access hole: a continuous circular capsulorhexis (CCC). We show that a modest sized CCC increases circumferential strains and decreases meridional strains by up to ∼20% and that curvatures change by up to ∼13%, particularly near the edge of the CCC. We submit that such changes can induce mechanobiological responses that are responsible, in part, for some of the long-term complications following cataract surgery.
Salivary cortisol among American Indians with and without posttraumatic stress disorder (PTSD): Gender and alcohol influences

Disruptions in hypothalamic-pituitary-adrenal regulation and immunity have been associated with posttraumatic stress disorder (PTSD). We examined the association of PTSD with diurnal rhythms in salivary cortisol in a convenience sample from a population-based study of male and female American Indians. Subjects with and without PTSD were identified from American Indians living on/near a Northern Plains reservation as part of a larger study. Over two days diurnal saliva samples were collected by staff at the University of Colorado Denver Clinical Research Center at waking, 30min after waking, before lunch, and before dinner. Generalized estimating equations linear regression models investigated the influence of PTSD on cortisol over time. The association of a lifetime diagnosis of PTSD with salivary cortisol level was assessed in subjects with complete data (PTSD: n=27; no PTSD n=32) for age, gender, and alcohol consumption in the past month. Subject mean age was 44 years, and 71% were women. When stratified by gender, women with a lifetime diagnosis of PTSD had significantly higher mean cortisol levels throughout the day than women without PTSD (p=0.01); but there was no significant association between PTSD and cortisol levels in men (p=0.36). The cortisol awakening response - the difference in cortisol levels from waking to 30min after waking - was not associated with PTSD in men or women. A lifetime diagnosis of PTSD may influence diurnal cortisol among American Indian women. These effects were independent of influences of current alcohol use/abuse. The unexpected elevation in cortisol in American Indian women with a lifetime diagnosis of PTSD may reflect acute anxiety associated with experiencing a number of novel tests in a strange location (e.g., cardiac imaging, medical, dental exams, etc.), or concurrent depression.
High energy (E<=1000 GeV) intranuclear cascade model for nucleons and pions incident on nuclei and comparisons with experimental data

An intranuclear cascade model for reactions of pions and nucleons with complex nuclei that should cover the energy range from about 50 MeV to about 1000 GeV has been developed. The model includes the effect of a diffuse nuclear surface, the Fermi motion of the bound nucleons within the nucleus, the exclusion principle, a local potential for nucleons, a localized reduction in the density of the nucleus during the development of the cascade, and the sequencing of the events correctly with time. Theoretical results from the model are compared with experimental data over the energy range \ensuremath{\sim} 3-1000 GeV. Within the cascade model, the equations that are used to represent the pion multiplicity from the reactions of nucleons and pions with the individual nucleons of the nucleus underestimates the number of shower particles produced by these individual nucleon interactions. In spite of this the predicted number of shower particles escaping from the nucleus, for 100-GeV nuclear interactions, is overestimated by about 25% for light nuclei to about 60% for heavy nuclei. The agreement for the number of escapes from the nucleus is somewhat better at lower interaction energies (\ensuremath{\sim} 10-20 GeV). Some of the major trends in the observed high energy data are predicted quite well. These include the energy independence of (a) the number of black tracks produced at interaction energies above 5 GeV, (b) the number of shower particles produced above 100 GeV, and (c) the radionuclides produced above 10 GeV. Other trends that are predicted fairly well are the small mass dependence of the shower particle multiplicity (factor of 2 increase predicted from carbon to lead; factor of 1.5 measured), and the change in the angular dependence of the multiplicity with mass. In absolute comparisons, the predicted total reaction cross sections are in good agreement with experimental data, and the cross sections for the production of radionuclides are in fair agreement.NUCLEAR REACTIONS Theoretical, intranuclear cascade method, ${\ensuremath{\sigma}}_{t}(A)$ for $p$ and $\ensuremath{\pi}$, ${〈n〉}_{\mathrm{shower}}$ and ${〈n〉}_{\mathrm{black}}$ vs ${E}_{\ensuremath{\pi}}$, $\ensuremath{\sigma}({\ensuremath{\theta}}_{\ensuremath{\pi}})\ensuremath{\Delta}{\ensuremath{\theta}}_{\ensuremath{\pi}}$ vs $A$, $\ensuremath{\sigma}({E}_{\ensuremath{\pi}},{E}_{p}:\ensuremath{\theta})$ for $p$ on Al, radiochemical $\ensuremath{\sigma}'\mathrm{s}$ for 11-and 300-GeV $p$ on $^{59}\mathrm{Co}$. All compared with experiment.
Optical gain in a strained-layer quantum-well laser

The optical gain and the refractive index change of a uniaxially stressed GaAs-Al/sub 2/Ga/sub 1-x/As quantum-well laser is studied theoretically using the multiband effective mass theory (k-p method) and density matrix formalism with intraband relaxations. It is found that uniaxial strain of the quantum well substantially alters the subband structures and the optical gain of the quantum-well laser. In particular, the gain of the TM mode increases while the gain of the TE mode decreases with increasing stress. Thus, the threshold current either decreases or increases with the stress, depending on whether the laser is operating in a TM or TE mode. >
Activity budgets, habitat use and body size in two coexisting species of sand wasps (Microbembex: Sphecidae, Hymenoptera)

. 1. Two superficially similar species of Microbembex, M.monodonta (Say) and M.cubana Bohart (Hymenoptera, Sphecidae, Nyssoninae), occur syntopically on Staniel Cay, a small Bahamian island (15 km2). 2. Nesting (female) and territorial (male) aggregations of M.cubana were smaller and more numerous than those of M.monodonta in the study site and on the island as a whole. 3. Both species had regular patterns of daily activities that required them to use a variety of microhabitats in the study area. 4. Males of both species defended territories from c. 09.00 to 12.00 hours EST (in May) and the left to feed on nectar until they retired to sleeping burrows, typically from 13.00 to 15.00 hours. Male M.monodonta were active longer each day and intermixed feeding and territorial defence more than did male M.cubana. 5. Females of both species were active for longer each day, from c. 08.30 to 15.30 hours, and intermixed their respective activities – hunting for provisions, feeding, and nest digging and maintenance – during each day more than did males. Female M.monodonta were active longer each day, rising earlier and retiring later, than female M.cubana. 6. In M.monodonta, females were larger (length, X =11.00 mm) than males (10.5 mm). In M.cubana, males were larger (11.1 mm) than females (10.4 mm). Although mean differences were small, they were highly significant (F=22.42; P<10−4) for the species-sex interaction. 7. Differences in activity budgets, habitat use, and sexual size dimorphism appear to be related. A combination of factors, particularly thermal constraints, possible competition, and different mating systems, could explain these patterns.
The health status of women with cerebral palsy

Abstract Objective: To determine preliminary associations between collected health status variables of women with cerebral palsy (CP) residing in the community. Design: Cross-sectional study using survey research. Participants: Sixty-three women residing in the community were administered the Telephone Questionnaire when contacted to arrange their visit to the study site located within the medical clinic of a local developmental services office. During the course of their visit to the study site, all 63 women completed the CP Study Protocol , in addition to the Mail-in Questionnaire upon completion of study participation. The women ranged in age from 20 to 74 years. Main Outcome Measures: Health status, consisting of four elements: (1) self-reported health status; (2) associated conditions; (3) secondary conditions; and (4) health behaviors (alcohol and tobacco use, physical activity, diet, and health care visit). Results: Women with CP residing in community living arrangements perceived themselves as healthy. The majority of women did not smoke (98%), had not consumed alcohol in the previous month (95%), and ate a balanced diet (52%). Participants also reported engaging in common physical activities (83%) and stretching and doing range-of-motion exercises in the previous week (43%), and participation in aerobic exercise in the previous week (43%). Sixty-eight percent (41 of 60) of the women walked, and more than 50% of the women did not require assistance with activities of daily living. The ability to walk and the use of a wheelchair were associated with participation in the common physical activities. The women reported associated conditions of mental retardation (34%), learning disabilities (26%), and a seizure history (40%). Additionally, the women in the sample reported the occurrence of several secondary conditions common among individuals with CP, including pain (84%), hip and back deformities (59%), bowel problems (56%), bladder problems (49%), poor dental health (43%), and gastroesphageal reflux (28%). Poor dental health was associated with a history of seizures, and associations were also found between pain and mental retardation, and between gastroesophageal reflux and mental retardation. Conclusions: Women with CP residing in the community perceived themselves as healthy, and the observed health status measures (eg, self-reported health, associated conditions, secondary conditions, and selected health behaviors) support this concept. For the most part, independent relationships were found between several of these measures indicating no significant association among the variables. Where associations were found, however, such as between walking and participation in physical activity, further investigation is warranted for a better understanding of their ramifications in the design of health promotion activities for women with CP.
Characterizing the Dependability of Distributed Storage Systems Using a Two-Layer Hidden Markov Model-Based Approach

Nowadays, dependability is of paramount importance in modern distributed storage systems. A challenging issue to deploy a storage system with certain dependability requirements or improve existing systems' dependability is how to comprehensively and efficiently characterize the dependability of those systems. In this paper, we present a two-layer Hidden Markov Model (HMM) to characterize the dependability of a distributed storage system, focusing on the layer of parallel file system. By training the model with observable measurements under faulty scenarios, such as I/O performance, we quantify the system dependability via a tuple of state transition probability, service degradation, and fault latency under those scenarios. Our experimental results on a distributed storage system with PVFS (Parallel Virtual File System) demonstrate the effectiveness of our HMM-based approach, which efficiently captures the behavior patterns of the target system under disk faults and memory overusage.
The response of single guard and down hair mechanoreceptors to moving air-jet stimulation.

The response properties of single guard (G) and down (D) hair afferent nerve fibers innervating the hairy skin of the hindlimb were studied in acute barbiturate-anesthetized cats. The purpose of the study was to identify and analyze the relative contribution of those stimulus features determining the discharge patterns evoked in single afferents by a fine air-jet stimulus moving across the skin and varying in force, velocity, position, direction and orientation. The response of single G hair afferents to moving air-jet stimuli reveals that the responsiveness of each fiber to stimuli with arbitrary orientation, direction and position within the receptive field (RF) displays an optimum velocity sensitivity which is not predictable from punctate data. Although the response pattern is remarkably consistent for each moving stimulus condition, there are significant differences in response as a function of stimulus orientation, direction and velocity. RF ‘maps’ constructed from the responses evoked as the air-jet traverses the skin reveal multiple zones of high and low sensitivity. The distribution of sensitive zones is remarkably consistent for maps constructed with stimuli varying in orientation, direction and velocity. It is apparent that the principal determinant of the response for a given stimulus transverse is the spatial distribution of sensitive spots throughout the RF. Although noticeably more uniform in sensitivity, the RFs of D hair afferents demonstrate similar properties. These findings indicate that G and D hair afferent nerve fibers respond more vigorously to moving stimuli than to stationary displacement and display complex RF inhomogeneities which must be taken into account for the study of central neuronal information processing and feature extraction.
Approach to the estimation of myocardial infarct size by analysis of precordial S-T segment and R wave maps.

Abstract To assess the correlation of S-T segment elevations and the height of R waves of the precordial electrocardiogram with myocardial infarct size, we performed 35 lead precordial electrocardiograms (maps) in 24 patients with uncomplicated acute anterior transmural myocardial infarction. The initial analysis was carried out in 14 patients. Infarct size was estimated from the integration, from normal baseline to baseline, of serial serum creatine kinase (CK) values obtained at 2 to 4 hour intervals and expressed as IU/liter·hours. The first electrocardiographic maps were recorded 12 hours or less after the onset of symptoms. All S-T segment elevations and R waves were summed for each map (∑S-T and ∑R). There were positive correlations between the ultimate CK infarct size and the initially recorded ∑S-T ( r = 0.69), the initially recorded log ∑R ( r = − 0.70) and the initial early decline in log ∑R per hour [(Δlog ∑R/Δhour)·10 3 , r = 0.88]. Therefore, these variables were combined in a multiple regression analysis; CK infarct size=0.23 ∑ S - T + 0.20 [( Δlog ∑ R / Δhour )·10 3 ]− 14.9 log ∑ R + 36.8 ( r = 0.97). In addition, on the basis of previous studies the initially recorded ∑S-T and log ∑R values were normalized with respect to time by calculating the expected ∑S-T value at 12 hours after the onset of symptoms (∑S-T 12 ) and the 12 hour interpolated values for ∑R (∑R 12 ). These values also showed a good correlation with infarct size: CK infarct size=0.37 ∑ S - T 12 + 0.16 [( Δlog ∑ R / Δhour )·10 3 ] t- 18.2 log ∑ R 12 + 40.4 ( r = 0.97). To validate this approach, 10 additional patients were studied prospectively. Correlations between CK infarct size and the various measurements from the serial precordial maps were similar to those in the first study group, and CK infarct size correlated well with the electrocardiographic infarct estimates ( r = 0.90 and r = 0.95, respectively). It is concluded that in selected patients CK infarct size can be directly related to the initial height of S-T segment elevations and the early rate of R wave decline and inversely related to later ∑R values, thereby providing a general approach for use in studies on the estimation of myocardial infarct size from precordial electrocardiographic maps.
Tephra Influence on Spokane-Flood Terraces, Bonner County, Idaho

In a previous study, our team described five Pleistocene Spokane-flood terraces with a ridge-and-trough surface topography in very gravelly outwash deposits we thought differed in age by <2000 years, but others later found to differ by about 6000 years (19 000 and 13 000 14C yr BP). Given the possibility of a longer time difference for soil development before deposition of any tephra, we obtained analytical data and reexamined the study thinking that an age difference of 6000 yr would have implications for soil classification and possibly suggest new series. Holocene tephra in the very fine sand (vfs) fraction (0.05-0.10 mm) ranges from 1% in the ridges to 93% in the troughs. The mean of the vfs fraction tephra content of soils on ridges of the higher, and presumably older, terraces (11%) is significantly less than that of soils on ridges of the lower and younger terraces (45%). The mean tephra content in the troughs (77%) does not vary by terrace level. The maximum fine-earth (<2 mm) allophane content of the youngest ridge is 96.3 g kg(-1) and that of the youngest trough is 95.4 g kg(-1). These amounts are greater than five times those of ridge soils on the older terraces. Only about 20 to 50% of the estimated Mount Mazama tephra fall remains on the older Bonner and Kootenai soils, whereas the older Rathdrum soil retains about 400% of the estimated Mount Mazama tephra fall. Minor amounts occur in the Histosol on the flood plain. Isotic 50- to 100-micrometer thick coatings on some A and B horizon sands indicate that weathering has been minor. Low spodic-horizon indicators (Al(o) and Fe(o) in subsurface horizons), and high ammonium oxalate extract optical densities of surface horizons, also suggest no fulvic acid leaching. Below the tephra influence, however, the outwash grains have anisotropic clay minerals showing that some weathering may have occurred before deposition of the tephra. The higher allophane content, higher NaF pH, and higher P-retention of lower terrace ridge soils, as compared with higher terrace ridge soils, results mostly from variation in the amount of their tephra and now justifies classifying ridge soils on higher and lower terraces into different taxa and opens the possibility of differentiating soil series by terrace level.
Why Do Female Aedes aegypti (Diptera: Culicidae) Feed Preferentially and Frequently on Human Blood?

Adult female Aedes aegypti (L.), the vector of dengue and yellow fever viruses, have an affinity for feeding on human blood and a tendency to forego feeding on sugar. This observation challenges two tenets of mosquito biology: (1) mosquitoes imbibe plant carbohydrates for synthesis of energy reserves and blood for reproduction and (2) egg production is reduced when mosquitoes feed on human blood compared with blood from other species. Sub-optimal amounts of the amino acid isoleucine in human blood (particularly free isoleucine in plasma) are thought to be responsible for lowered egg production when human blood is ingested. We tested the hypothesis that feeding on human blood is associated with a selective advantage for Ae. aegypti and is an underlying reason for this mosquito's intimate and epidemiologically important relationship with human beings. Our five experiments examined the effects of different isoleucine concentrations on accumulated energy reserves, frequency of host contact, survival, and egg production. When mosquitoes imbibed blood meals over a 7- to 10-d period and were not fed sugar, increased isoleucine concentration decreased energy reserves and did not increase egg production. Aedes aegypti took smaller but more frequent blood meals when feeding on a low-isoleucine human host daily compared with a high-isoleucine mouse host. Previous reports that isoleucine enhances egg production were confirmed only when females were fed sugar, an unusual behavior for most domestic Ae. aegypti populations. Females fed human blood and water had greater age-specific survival (l(x)), reproductive output (m(x)), and cumulative net replacement (R0) than cohorts fed human blood plus sugar or isoleucine-rich mouse blood with or without access to sugar. The unique isoleucine concentration of human blood is associated with Ae. aegypti's unusual propensity to feed preferentially and frequently on humans--a behavior that increases this mosquito's fitness, synthesis of energy reserves, and contact with human hosts, making it an especially effective disseminator of human pathogens.
Determination of Cycloheximide and Its Degradation Products Alone and in Mixtures

Procedures for determining cycloheximide and its degradation products, anhydrocycloheximide, 2,4-dimethylcyclohexanone, and glutarimide β -acetaldehyde, separately and in mixtures are devised. They are based on the relative oximation reactivities of the carbonyl compounds under specified conditions. The method is useful for aqueous and methanolic solutions. Simultaneous spectrophotometric assay of anhydrocycloheximide is necessary for assay of mixtures. The use of potentiometry and imide analytical methods expands the utility of the method to cases where imide solvolysis may have occurred or where the degradation products are derived from an unknown amount of cycloheximide precursor.
Effects of the presence of the mammary gland on expression of neutrophil adhesion molecules and myeloperoxidase activity in periparturient dairy cows.

Neutrophil function is reduced in periparturient dairy cows. Possible factors that reduce neutrophil function include endocrine changes associated with parturition and metabolic stresses associated with lactogenesis. In this study, mastectomized and intact cows were studied to specifically examine the effects of lactogenesis on neutrophil function in periparturient cows. Expression of adhesion molecules on neutrophils (L-selectin, mediating capture and rolling adhesion, and β2integrin, mediating tight adhesion vital to egress) and neutrophil myeloperoxidase activity (an index of bactericidal activity) were assessed in mastectomized and intact cows. Expression of L-selectin decreased at parturition followed by rapid recovery to prepartum values in both intact and mastectomized cows. Expression of β2-integrins increased in intact cows at parturition but not in mastectomized cows. Expression of β2-integrins was greater in intact cows than in mastectomized cows throughout the study. Neutrophil myeloperoxidase activity decreased from baseline prepartum values as parturition approached in both intact and mastectomized cows, which suggests the endocrine changes associated with the act of parturition are predominant factors causing loss of neutrophil function. Myeloperoxidase activity recovered to prepartum values within a week of parturition in mastectomized cows; however, myeloperoxidase activity remained depressed in neutrophils obtained from intact cows throughout the first 20 d of lactation. The presence of the mammary gland and its attendant metabolic stresses slowed recovery of neutrophil function, which suggests that the metabolic stress of lactation exacerbated periparturient immunosuppression.
A separation of two randomness concepts

In this paper we give an affirmative answer to a conjecture by Lutz (1992). That is, we will show that there is a Schnorr random sequence which is not rec-random.
Modulation of the IL-10/IL-12 cytokine circuit by interferon-β inhibits the development of epitope spreading and disease progression in murine autoimmune encephalomyelitis

IFN-beta has been shown to be effective in the treatment of multiple sclerosis (MS). However, the primary mechanism by which IFN-beta mediates its therapeutic effect remains unclear. Recent studies indicate that under defined conditions, IFN-beta may downregulate DC expression of IL-12. We and others have shown that IFN-beta may also downregulate IL-10. In light of the recently proposed paradigm that an IL-10/IL-12 immunoregulatory circuit controls susceptibility to autoimmune disease, we examined the effect of IFN-beta on the development and behavior of the autoreactive T cell repertoire during experimental autoimmune encephalomyelitis (EAE), an animal model sharing many features with MS. SWXJ mice were immunized with the immunodominant p139-151 determinant of myelin proteolipid protein (PLP), and at onset of EAE were treated every other day with IFN-beta. After eight weeks of treatment, we assessed autoreactivity and observed no significant IFN-beta effect on splenocyte proliferation or splenocyte production of IFN-gamma, IL-2, IL-4, or IL-5 in response to the priming determinant used to initiate disease. However, in IFN-beta treated mice, the cytokine profile in response to the priming immunogen was significantly skewed toward an increased production of IL-10 and a concurrent decreased production of IL-12. Moreover, the in vivo modulation of the IL-10/IL-12 immunoregulatory circuit in response to the priming immunogen was accompanied by an aborted development of epitope spreading. Our results indicate that IFN-beta induces a reciprocal modulation of the IL-10/IL-12 cytokine circuit in vivo. This skewed autoreactivity establishes an inflammatory microenvironment that effectively prevents endogenous self-priming thereby inhibiting the progression of disease associated with epitope spreading.
ISAR motion detection and compensation using genetic algorithms

Based on the point scatterer model, the radar signal can be effectively analyzed using the joint time-frequency (JTF) method. The basis functions of a few primary point scatterers are believed to carry target motion information essential to the ISAR imaging process. One major problem with the JTF method is the computation load associated with the exhaustive search process for motion parameters. In this paper, genetic algorithms (GA) are used to for the parameterization process in the JTF method. Real and binary coded GA are investigated and their performance compared with the exhaustive search. It is shown that a significant amount of time can be saved while achieving almost the same image quality by using real-coded GA.© (2001) COPYRIGHT SPIE--The International Society for Optical Engineering. Downloading of the abstract is permitted for personal use only.
Comparative isosteric ion adsorption for minerals

A comparative isosteric ion adsorption study for minerals (kaolinite, rutile, and quartz) was performed in aqueous solutions of CaCl2, LaCl3, and Th(NO3)4 in the presence of the neutral salt NaCl. It was observed that the concentration of Ca(2+) ions required to produce a standard reduction in the electrophoretic mobility of mineral particles was always appreciably greater than the concentration required for the Th(4+) ions. The effectiveness of adsorption of the cations differed from particle to particle and showed that ion adsorption on a mineral surface depends, among other things, on the nature of the mineral surface and on the particular adsorbed cation. The number of cation binding sites on mineral surfaces and the electrochemical free energies of cation adsorption were calculated. It was found that the adsorption energy of La(3+) and Th(4+) ions on rutile, kaolinite, and quartz was greater than that of Ca(2+) on these minerals.
Density Functional Study of Fe(CO)3 and Fe(CO)3(L) with H2 and C2H4, where L = H2 or C2H4: Reactions Relevant to Olefin Hydrogenation

The bonding and geometries of H2Fe(CO)3, H2Fe(CO)3(C2H4), and HFe(CO)3(C2H5), which are species relevant to iron carbonyl-catalyzed olefin hydrogenation, are analyzed using density functional theory (DFT). These calculations indicate that H2Fe(CO)3 and H2Fe(CO)3(C2H4) are respectively triplet and singlet dihydrogen complexes with H2Fe(CO)3(C2H4) lower in energy than HFe(CO)3(C2H5) by a modest amount (10.2 kcal/mol with BP86/LACV3P**). Further, it is likely that when H2Fe(CO)3(C2H4) forms, it can rearrange to form the HFe(CO)3(C2H5) complex. The reductive elimination of C2H6 from HFe(CO)3(C2H5) is exothermic, whether it is accompanied by or precedes ethylene addition.
Spin suceptibility and specific heat bi-layer high-Tc cuprates: on the origin of scaling and universality

Abstract The anomalies in the spin susceptibility X s ( T ) and specific heat C V ( T ) in the high- T c cuprates are shown to have origin in a non-degenerate electron component. This arises when the chemical potential μ is tuned near the top of a 2D band submerged just below the Fermi surface. In bi-layer cuprates the model predicts a scaling of the form: X s (T, x) = Xs (W(x)/T) and C V(T, x)/T = γ(W(x)/T) , where doping-dependent scaling parameter W is determined by the location of μ relative to the top of the non-degenerate band. We compare the results of this model with experiments and find the predicted type of scaling in the susceptibility of under, optimally, and overdoped (TlSr 2 (Lu 1− x Ca x )Cu 2 O y samples. We also argue that the scaling curves X s ( y ) and γ ( y ) may be universal for a certain class of bi-layer cuprates.
Institutional change and evolution

In the midst of incessant talk about restructuring, downsizing, and reinventing national organizations and institutions, how do we account for the organizational, technological, and cultural change that has taken place so rapidly since 1989? In a recent book on managing and financing institutions of higher education (Johnson and Rush, 1995), one of the editors is quite emphatic in stating that, "Thus far, change in higher education has been an evolutionary, not revolutionary process" (p. 13). Can we find then a satisfying explanation in Darwin's theory of natural selection--should we look for more dramatic reasons in adaptation theory and what we used to call Social Darwinism? For colleges and universities, how much sense does it make to say that each societal institution has its own culture and evolves in its own way? No one should doubt that organizations and institutions change structurally and functionally over a period of time--but how quickly can institutions of higher education change in response to the organizational and technological changes evident in the international competition of multinational business corporations that are technologically driven? Most of us would agree that universities have changed significantly since the establishment of Johns Hopkins University in the 1880s; we would agree that they have changed even more since the end of World War II. We would not agree, however, on the usefulness of evolutionary theory in explaining the organizational and technological changes we have witnessed in the past decade. NATURAL SELECTION Once regarded as the mainstay of Social Darwinism, the "survival of the fittest" is surely a tautology that explains nothing. We must concede that some institutions survive while others perish (or decline in prestige, status, or reputation), and we should acknowledge that some institutions display a remarkable
Is rural residency a risk factor for overweight and obesity for U.S. children

LUTFIYYA, MAY NAWAL, MARTIN S. LIPSKY, JENNIFER WISDOM-BEHOUNEK, AND MELISSA INPANBUTR-MARTINKUS. Is rural residency a risk factor for overweight and obesity for U.S. children? Obesity. 2007;15:2348–2356. Objective: Despite studies suggesting that there is a higher prevalence of overweight or obese children in rural areas in the U.S., there are no national studies comparing the prevalence levels of overweight or obese rural to metropolitan children. The objective of this research was to examine the hypothesis that living in a rural area is a risk factor for children being overweight or obese. Research Methods and Procedures: Using the National Survey of Children’s Heath, the prevalence of overweight and/or obese rural children was compared with that of children in metropolitan settings. Multivariate analyses were performed on the data to detect if differences varied by health services use factors or demographic factors, such as household income, gender, and race. Results: Multivariate analysis revealed that overweight or obese children 5 years of age were more likely to live in rural rather than metropolitan areas (odds ratio 1.252; 95% confidence interval, 1.248, 1.256). Rural overweight U.S. children 5 years of age of age were more likely than their metropolitan counterparts to: be white, live in households 200% of the federal poverty level, have no health insurance, have not received preventive health care in the past 12 months, be female, use a computer for non-school work 3 hours a day, and watch television for 3 hours a day. In addition, they were more likely to have comorbidities. Discussion: Living in rural areas is a risk factor for children being overweight or obese.
Developing the Scholar's Ethos in Minority High School Students The Vital Link to Academic Achievement

High school students in "EXCEL" are prepared for college by enrichment, career explorations, and the "demystification " of college.
Recent Advances in Cardiac SPECT Instrumentation and System Design

Recent advances in clinical cardiac SPECT instrumentation are reviewed from a systems perspective. New hardware technologies include pixelated scintillator and semiconductor detector elements; photodetectors such as position-sensitive photomultiplier tubes (PSPMT), avalanche photodiodes (APD) and silicon photomultipliers (SiPM); and novel cardiac collimation methods. There are new approaches for positioning detectors and controlling their motion during cardiac imaging. Software technology advances include iterative image reconstruction with modeling of Poisson statistics and depth-dependent collimator response. These new technologies enable faster acquisitions, the lowering of administered activity and radiation dose, and improved image resolution. Higher sensitivity collimators are a significant factor enabling faster acquisitions. Several clinical systems incorporating new technologies are discussed and different system designs can achieve similar performance. With detector elements such as APDs, SiPMs and semiconductors that are insensitive to magnetic fields, the potential for cardiac SPECT imagers that are MRI compatible opens up new frontiers in clinical cardiac research and patient care.
Generalization of a formula of Touchard for Catalan numbers

Abstract In this paper a general identity is proved which includes among its special cases a recurrence formula for Catalan numbers given by J. Touchard in 1924.
How to ask: Older adults’ preferred tools in health outcome prioritization

Abstract Objective To assess older adults’ attitudes toward eliciting health outcome priorities. Methods This observational cohort study of 356 community-living adults age ≥65 included three tools: (1) Health Outcomes: ranking four outcomes (survival, function, freedom from pain, and freedom from other symptoms); (2) Now vs. Later: rating importance of current versus future quality of life; (3) Attitude Scale: agreement with statements about health outcomes and current versus future health. Results Whereas 41% preferred Health Outcomes, 40% preferred the Attitude Scale. Only 7–12% rated any tool as very hard or hard. In bivariate analysis, participants of non-white race and with lower education, health literacy, and functional status were significantly more likely to rate at least one of the tools as easy ( p Conclusions There is variability in how older persons wish to be asked about health outcome priorities. Few find this task difficult, and difficulty was not greater among participants with lower health literacy, education, or health status. Practice implications By offering different tools, healthcare providers can help patients clarify their health outcome priorities.
Characterization of high-affinity antifluorescyl IgM antibodies

Abstract High-affinity IgM rabbit antibodies were elicited using the fluorescein hapten system. Purity and identification of IgM and IgG anti-fluorescyl antibodies was determined by immunoelectrophoresis and SDS-polyacrylamide gel electrophoresis. Ultracentrifugation studies verified that liganded antibodies were of a high mol. wt (901 kd). Comparative analyses of IgM and IgG anti-fluorescyl antibody active sites substantiated the observation that purified IgM preparations, similar to their IgG counterparts, possessed high-affinity antibody active sites. Dissociation rate data confirmed that some IgM molecules within the purified antibody populations possessed association constants at 1011M−1, comparable with values of 1011M−1 or greater obtained for some anti-fluorescein IgG populations studied in this laboratory. A diffusion-controlled association rate of 4.6 × 108M−1 sec−1 (Levison et al., 1971) was assumed in dissociation rate calculations. This is the first report of purified IgM antibodies possessing exceptionally high affinities.
2. Boron trifluoride activated 3-thiazolines. A versatile synthesis of thiophenes

Abstract Thiazolidines generated by the addition of ketone enolates to boron trifluoride activated 2,2,5-trialkyl-3-thiazolines undergo a facile acid catalyzed conversion to di- and trisubstituted thiophenes.
Experimental passive SAR imaging exploiting LTE, DVB, and DAB signals

Commercial OFDM signals of opportunity have been studied for numerous radar applications, including SAR imaging. This paper demonstrates the utility of long term evolution (LTE), digital video broadcast (DVB), and digital audio broadcast (DAB) signals for producing passive SAR images by employing a previously derived OFDM matched filter model. Both full matched filters and partially matched filters (using only a priori known signal features) are considered for generating phase history from collected receiver data. Small-scale, experimental SAR images are produced illustrating the merits of the processing schemes and signals of opportunity.
Inner bremsstrahlung in mu-meson decay

The transition probability for decay of theμ-meson with the emission of an additional photon is computed on the basis of the most general two-component theory of the neutrino with lepton conservation. The estimated ratio of one radiative event per 105 decays suggests that the experiment may be feasible in the near future.
A Method for Measuring Functional Residual Capacity in Neonates with Endotracheal Tubes

This study evaluates a new 60-s closed circuit helium (He) dilution technique for determination of functional residual capacity (FRC) in intubated neonates independent of snall gas leaks present around uncuffed endotracheal (ET) tubes. By analyticaly relating the fall in He concentration due to mixing with that due to leakage it is possible to predict the final equflibration concentration of He and, therefore, correct for ET tube leaks. The system (120 ml) contains an air pump, He meter, breathing bag in cylinder, a strip chart readout, and solenoid value. Continuous positive airway pressure (CPAP) or ventilator pressure can be applied during testing. One hundred in vitro measurements of FRC ranging from 5-100 cc in both leak and nonleak models were performed and were accurate to within ±7.8% standard deviation. Functional residual capacity measurements were also performed in 30 infants (weight 600-4400 gm).
Diffusion as a probe of peptide-induced membrane domain formation.

Recently, we have shown that association with an antimicrobial peptide (AMP) can drastically alter the diffusion behavior of the constituent lipids in model membranes (Biochemistry 49, 4672−4678). In particular, we found that the diffusion time of a tracer fluorescent lipid through a confocal volume measured via fluorescence correlation spectroscopy (FCS) is distributed over a wide range of time scales, indicating the formation of stable and/or transient membrane species that have different mobilities. A simple estimate, however, suggested that the slow diffusing species are too large to be attributed to AMP oligomers or pores that are tightly bound to a small number of lipids. Thus, we tentatively ascribed them to membrane domains and/or clusters that possess distinctively different diffusion properties. In order to further substantiate our previous conjecture, herein we study the diffusion behavior of the membrane-bound peptide molecules using the same AMPs and model membranes. Our results show, in cont...
The effect of grain size, porosity and yttria content on the thermal conductivity of nanocrystalline zirconia

In order to accommodate the ever increasing inlet temperatures of gas turbines, air plasma sprayed (APS) or electron beam physically vapor deposited (EB-PVD) yttria stabilized zirconia thermal barrier coatings (TBC`s) are used to insulate the metallic surfaces. Because of its historic use as a TBC, the thermal diffusivity and conductivity of single crystal and polycrystalline stabilized zirconia have been the subject of numerous experimental investigations. However, to the knowledge of the authors, the thermal conductivity of nanocrystalline (gain size < 100 nm) zirconia has not yet been determined. To ascertain whether or when grain boundary effects begin to dominate thermal conductivity, k, values for a variety of nanocrystalline zirconias of different densities (60--100%), grain sizes (30--400 nm), and purities (0--15wt.% yttria) are compared in this work. Finally the measured values are compared with the thermal conductivities of commercially available air plasma sprayed (APS) and electron beam physical vapor deposited (EB-PVD) coatings.
Two integrative win-win negotiating strategies

A theoretical foundation is developed for a negotiating role-play. Two integrative (win-win) negotiating strategies, logrolling and bridging, are discussed. The dual concern model provides a conceptual perspective for comparing and contrasting the two strategies. Refocusing on underlying interests is seen as the condition that differentiates bridging from logrolling. Existing role-playing exercises with logrolling or bridging potential are briefly described.
TPA inhibits the synthesis of androgens and cortisol and enhances the synthesis of non-17α-hydroxylated steroids in cultured human adrenocortical cells

Previously, we showed that 12-0-tetracecanoyl phorbol 13-acetate (TPA), an activator of protein kinase C, is a raitogen for fetal human definitive zone adrenocortical cells in culture. In the present experiments, TPA inhibited forskolin-stimulated cortisol, dehydroepiandrosterone (DHEA), and dehydroepiandrosterone sulfate (DHEAS) synthesis, and enhanced forskolin-stimulated progesterone and corticosterone synthesis. These changes in the pattern of steroidogenesis were shown to result from changes in enzyme activities after forskolin treatment. TPA increased forskolin-stimulated 3β-phydroxysteroid dehydrogenase (3β-HSD) 2-fold, while depressing forskolin-stimulated 17c-hydroxylase to basal values. DHEA sulfotransferase increased 3-fold on transfer of human adrenocortical cells from serum-containing to defined, serumfree n:ediur_; TPA inhibited this increase. Experiments in which TPA was added at various times during the time course of forskolin stimulation of 17α-hydroxylase showed that TPA prevents the in...
Reliability and validity of the Frail Elderly Functional Assessment questionnaire

Measuring functional activity for elderly at very low functional levels remains a challenge because many functional instruments have not been standardized in a frail elderly population. The Frail Elderly Functional Assessment questionnaire (FEFA) is a 19-item, interviewer-administered questionnaire designed to assess function in frail elderly at a very low activity level. The purpose of this study was to determine the reliability and validity of this instrument in a frail elderly population. Two groups of subjects over 65 yr old were selected to test the reliability and validity of this questionnaire. Test-retest reliability was determined by correlating the responses of 29 homebound (including nursing home-bound) subjects who answered the questionnaire on two occasions 2 wk apart. To assess the validity of the FEFA, the questionnaire was administered to 23 frail, homebound (including nursing home-bound) elderly subjects who had a Mini-Mental State Examination score of > or = 18. Validity was determined by correlating patient responses to direct observations by the investigators of tasks addressed in the questionnaire. Correlation was also determined against the Katz's Activity of Daily Living index, Lawton's Instrumental Activity of Daily Living index, and the Barthel index. The reliability coefficient was 0.82. Correlation between the FEFA questionnaire and direct observation of questionnaire task performance was 0.90. Construct validity against the Katz's Activity of Daily Living, Lawton's Instrumental Activity of Daily Living, and the Barthel index showed correlations of 0.86, 0.67 and 0.91, respectively. Initial data indicate that the FEFA is a valid and reliable instrument that may be useful in assessing function in frail elderly people.
Reminder: Similar and differential effects in amnesic and weakly trained rats

Two experiments investigated the effectiveness of reminder treatments in potentiating memory in subjects given either strong fear conditioning and ECS or weak fear conditioning. In Experiment I, reminder increased memory in both groups. Experiment II substantiated this finding under somewhat different conditions and also showed that, in one reminder condition, increased memory was obtained in subjects fear conditioned and given ECS while no effect was noted in subjects given weak fear conditioning. The finding of differential modification of memory with reminder in these two groups suggests that a previous interpretation, based on the usual finding of parallel modification with reminder in these groups, may be incorrect. Moreover, these data suggest that the major effect of ECS is on memory retrieval processes.