cssi/SciSciGPT-SciSciNet huggingface dataset:
Clinical Reasoning: A 28-Year-Old Woman With Vision Loss and an Unusual Gait

A 28-year-old woman with a history of migraine with visual aura and normal growth and development presented with gradually progressive vision loss since the age of 13 years (legally blind since the age of 20 years) and with later development of gait imbalance and falls beginning at the age of 25. Ancestry was Dominican on both sides, and the family history was significant for a father with an onset of tremor, dysarthria, and balance difficulties at the age of 47 and a paternal half-sister with an onset of tremor at the age of 6, both without visual loss. Her 3 brothers and 2 children were healthy.
Development of coarse-grained model for a minimal stratum corneum lipid mixture

Molecular dynamics simulations of mixtures of the ceramide N-(tetracosanoyl)-sphingosine (NS), cholesterol, and a free fatty acid are performed to gain a molecular-level understanding of the structure of the lipids found in the stratum corneum layer of skin. A new coarse-grained model for cholesterol, developed using the multistate iterative Boltzmann inversion method, is compatible with previously developed coarse-grained forcefields for ceramide NS, free fatty acid, and water, and validated against atomistic simulations of these lipids using the CHARMM force field. Self-assembly simulations of multilayer structures using these coarse-grained force fields are performed, revealing that a large fraction of the ceramides adopt extended conformations, which cannot occur in the bilayer structures typically studied using simulation. Cholesterol fluidizes the membrane by promoting packing defects and it is observed that an increase in cholesterol content reduces the bilayer height, due to an increase in interdigitation of the C24 lipid tails, consistent with experimental observations. Through the use of a simple reverse-mapping procedure, a self-assembled coarse-grained multilayer system is used to construct an equivalent structure with atomistic resolution. Simulations of this atomistic structure are found to closely agree with experimentally derived neutron scattering length density profiles. Significant interlayer hydrogen bonding is observed in the inner layers of the atomistic multilayer structure that are not found in the outer layers in contact with water or in equivalent bilayer structures. These results identify several significant differences in the structure and hydrogen bonding of multilayer structures as compared to the more commonly studied bilayer systems, and, as such, highlight the importance of simulating multilayer structures for more accurate comparisons with experiment. These results also provide validation of the efficacy of the coarse-grained forcefields and the framework for multiscale simulation.
A data-driven recurrent event model for system degradation with imperfect maintenance actions

Although a large number of degradation models for industrial systems have been proposed by researchers over the past few decades, the modeling of impacts of maintenance actions has been mostly limi...
A log rank type test in observational survival studies with stratified sampling

In randomized clinical trials, the log rank test is often used to test the null hypothesis of the equality of treatment-specific survival distributions. In observational studies, however, the ordinary log rank test is no longer guaranteed to be valid. In such studies we must be cautious about potential confounders; that is, the covariates that affect both the treatment assignment and the survival distribution. In this paper, two cases were considered: the first is when it is believed that all the potential confounders are captured in the primary database, and the second case where a substudy is conducted to capture additional confounding covariates. We generalize the augmented inverse probability weighted complete case estimators for treatment-specific survival distribution proposed in Bai et al. (Biometrics 69:830-839, 2013) and develop the log rank type test in both cases. The consistency and double robustness of the proposed test statistics are shown in simulation studies. These statistics are then applied to the data from the observational study that motivated this research.
Expression of Epidermal Growth Factor Receptor (EGF-R) and Erb-B2 (HER 2/NEU) in Glioblastoma (GEM): Prognosttc Relevance

Archival material from 17 untreated primary adult GEMs were analyzed retrospectively using immunocytochemistry for the expression of EGF-R and ErbB2. Patients were divided into long term survivors (LTS) (N=10, median survival >4 yrs) and short term survivors (STS) (N=7, median survival 61 wks, mean ± SEM time to recurrence 22 ± 3 wks). There were no biologically significant differences between the groups in terms of age, post-operative Karnofsky status, or post-operative treatment (standard cranial radiation and chemotherapy). 6/7 of the STS had >90% of tumor resected compared with 6/10 of the LTS. All STS underwent debulking reoperation at suspected recurrence, confirming tumor regrowth as the cause of death in all STS. Histologically diagnostic paraffin sections were stained with monoclonal antibodies to EGF-R and ErbB2. Tumor staining was scored as 1 to 3: scant/ negative; ≦25% but <75% positive, or ≦75% positive. Scores of 2 and 3 were considered positve (+). Each tumor section was scored for positivity by 3 independent observers, blinded as to patient’s name and history. There was general concordance between all three observers. All LTS were EGF-R negative/ scant and 7/10 were ErbB2 negative/scant. 4/7 STS were EGF-R+, 5/7 were ErbB2+, and 4/7 were positive for both proteins. Recurrrent tumors in STS had increased expression of EGF-R in 4/7 of cases and of ErbB2 in 7/7 cases over the pretreatment baseline. EGF-R negativity correlated best with long term survival, while ErbB2 positivity better predicted short term survival. Increased growth factor expression appears to be associated with aggressive clinical behavior and treatment resistance.
Hall Effect and Magnetoresistive Sensors

Usually magnetic sensors output a signal voltage along with little or no current. The magnetic fields sensed may vary over an extremely broad range. Magnetic sensors using the Hall effect are very common, small, and inexpensive. This chapter examines the behavior, accuracy, and construction of typical Hall sensors. Along with the Hall effect, it describes a related parameter called magnetoresistance. The chapter discusses Hall voltage equation, Hall effect conductivity tensor, finite-element computation of Hall fields, position sensors, mangnetoresistive heads, and giant magnetoresistance (GMR) sensors.
A Promising Tool for Helping Vulnerable Workers? An Exploration of the Use of Employee Assistance Programs (EAPs) to Help Low-Wage Workers on College Campuses.

Employee assistance programs, or EAPs, are an employeebenefit designed to help workers meet their work and familyneeds. However, questions have been raised about the design,utilization, and scale of services that EAPs make possible forlow-wage workers. This article explores whether on collegecampuses an EAP benefit can simultaneously meet the needsof faculty and professional staff as well as hourly workers inparking and security, janitorial and facility, and dining services.Findings derived from interviews and a literature review revealmany promising practices worthy of replication by collegesand universities; however, this investigation also revealed thelimits of EAPs’ usefulness for “working poor” service workersin higher education.
Inadequacy of high K+/nigericin for calibrating BCECF I. Estimating steady-state intracellular pH

Intracellular pH (pHi) was measured in single vascular smooth muscle (VSM) cells, cultured from rabbit abdominal aorta, using 2',7'-bis(carboxyethyl)-5(6)-carboxyfluorescein (BCECF) on a microscope...
Temporal discontiguity is neither necessary nor sufficient for learning-induced effects on adult neurogenesis

Some, but not all, types of learning and memory can influence neurogenesis in the adult hippocampus. Trace eyeblink conditioning has been shown to enhance the survival of new neurons, whereas delay eyeblink conditioning has no such effect. The key difference between the two training procedures is that the conditioning stimuli are separated in time during trace but not delay conditioning. These findings raise the question of whether temporal discontiguity is necessary for enhancing the survival of new neurons. Here we used two approaches to test this hypothesis. First, we examined the influence of a delay conditioning task in which the duration of the conditioned stimulus (CS) was increased nearly twofold, a procedure that critically engages the hippocampus. Although the CS and unconditioned stimulus are contiguous, this very long delay conditioning procedure increased the number of new neurons that survived. Second, we examined the influence of learning the trace conditioned response (CR) after having acquired the CR during delay conditioning, a procedure that renders trace conditioning hippocampal-independent. In this case, trace conditioning did not enhance the survival of new neurons. Together, these results demonstrate that associative learning increases the survival of new neurons in the adult hippocampus, regardless of temporal contiguity.
Flooding for combat-related stress disorders: Assessment of anxiety reduction across traumatic memories

An issue of major concern in the behavioral treatment of posttraumatic stress disorders (PTSD) is the extent to which the extinction of anxiety to the memory of one event generalizes to other traumatic events that the individual may have experienced. In the present study each of two Vietnam veterans presented multiple traumatic events from combat which reoccurred in the form of intrusive thoughts, nightmares, and flashbacks. Using imaginal flooding as the treatment, it was possible to document the effect of treating the memory of one traumatic event upon the anxiety-provoking nature of the remaining traumas. For the first patient, subjective units of distress measures (SUDS) verified treatment efficacy and provided some evidence for generalization of extinction along thematic (stimulus) cues. With the second patient, physiological data in conjunction with SUDS ratings documented the relative independence of the anxiety associated with different traumatic events.
Isolation of 3-methylcrotonyl-coenzyme A carboxylase from bovine kidney

Abstract 3-Methylcrotonyl-CoA carboxylase (MCase), an enzyme of the leucine oxidation pathway, was highly purified from bovine kidney. The native enzyme has an approximate molecular weight of 835,000 as measured from exclusion limits by polyacrylamide gel electrophoresis at pH 7.3. Polyacrylamide gel electrophoresis in the presence of sodium dodecyl sulfate demonstrated two subunits, identified as a biotin-free subunit (A subunit; Mr = 61,000) and a biotin-containing subunit (B subunit; Mr = 73,500). The biotin content of the enzyme was 1 mol/ 157,000 g protein, consistent with an AB protomeric structure for the enzyme. The isoelectric point of the enzyme was found to be 5.4. Maximal MCase activity was found at pH 8 and 38 °C in the presence of Mg2+ and an activating monovalent cation such as K+. Kinetic constants (Km values) for the enzyme substrates were: 3-methylcrotonyl-CoA, 75 μ m ; ATP, 82 μ m ; HCO3−, 1.8 m m . Certain acyl-CoA derivatives, including crotonyl-CoA, (2Z)-3-ethylcrotonyl-CoA, and acetoacetyl-CoA, were also substrates for the enzyme. Some data on inhibition of the enzyme by acyl-CoA derivatives, and sulfhydryl- and arginyl-reagents, are presented.
Casein hydrolysate. II. Functional properties of peptides

Abstract Acid casein was continuously modified using immobilized (IM-) trypsin, chymotrypsin and Rhozyme-41. The objective was bulk production of hydrolysates with desirable functional attributes. The degree of modification was controlled by regulating the flow rate through an IM-enzyme bioreactor at 4°C. Polyacrylamide gel electrophoresis indicated little change in the major caseins. C 18 reverse phase high performance liquid chromatography (HPLC) on the other hand showed the formation of large amounts of peptides only at the highest level of treatment. C 8 HPLC, following the selective extraction of peptides by membrane filtration, showed small amounts of peptide mixtures even in the least treated samples. The emulsifying properties of the casein was markedly improved by modification. IM-Rhozyme-41 gave up to a 3.2-fold increase in the emulsifying activity, whereas emulsion stability was improved using IM-trypsin. Oil holding capacity of the preparations was best when IM-trypsin was used even though all the enzymes tested improved it markedly. The solubility and thermostability of all levels of treatments were far better than those for the control.
The Relationship between Creativity and Ego Development

Summary Fifty-eight female undergraduate students were administered the Torrance Tests of Creative Thinking (TTCT), Figural form B, and the Washington Sentence Completion Test in order to investigate the hypothesis of a positive relationship between creativity and ego development. A Spearman rank order correlation coefficient was computed for ego development and each TTCT creativity factor (fluency, flexibility, originality, and elaboration), as well as a total composite creativity score. All creativity scores correlated with ego development at the .01 level, except for originality, which correlated at the .05 level. Results were discussed in terms of Maslow's theories concerning highly developed persons, and possible preconscious aspects of the creative process. Conclusions were drawn, and recommendations for further research were made.
Vibrational relaxation of A CF2(ν2 = 1–6 in non-reactive collisions

Abstract Rate constants have been measured for collisional energy transfer as a function of vibrational quantum number in the first excited singlet state of the CF2 radical. Total vibrational deactivation rates at T = 295 K are reported for the bending mode, A CF2 (2n), for 1 ⩽ n ⩽ 6 in collisions with He, Ne, N2 and SF6 which do not electronically quench the A CF2. The predominant pathway of vibrational deactivation is the single-quantum change A CF2 (2n) + M - A CF2 (2n−1) + M + ΔE = 494 cm−1. However, as n increases, rates for two- and three-quantum changes become increasingly important. These results are generally consistent with the principles of vibrational energy transfer found previously for ground electronic state molecules.
Decomposition of cowpea and millet amendments to a sandy Alfisol in Niger

Current inputs of organic materials to cropped lands on sandy Alfisols and Entisols in Sahelian West Africa are insufficient to arrest soil organic matter (SOM) decline. Crop residues and green manures require proper management in order to maximize their contribution to nutrient supply and SOM maintenance. The objectives of this study were to quantify the rates of C and N mineralization from cowpea (Vigna unguiculata (L.) Walp.) green manure, cowpea residue, and millet (Pennisetum glaucum (L.) R.Br.) residue under field conditions in Niger and to determine the effect of these organic amendments on pearl millet yield. Millet was grown (1) as sole crop, (2) as intercrop with cowpea, (3) as intercrop with cowpea that was incorporated as green manure during the second half of the growing season, (4) with incorporated cowpea residue (2000 kg ha−1), (5) with millet residue mulch (3000 kg ha−1), and (6) with N fertilizer. Carbon loss as CO2 from soil with and without organic amendment was measured three times per week during the growing season. Nitrogen fertilizer increased millet yield only in a year with a favorable rainfall distribution. Cowpea grown in intercrop with millet during the first part of the growing season and subsequently incorporated as green manure between millet rows increased millet grain yield in a year with sufficient early rainfall, which could be attributed to the rapid rate of decomposition and nutrient release during the first 3 weeks after incorporation. In a year with limited early rainfall, however, densely planted green manure cowpeas competed for water and nutrients with the growing millet crop. Incorporated cowpea residue and millet residue mulch increased millet yield. Surface applied millet residue had high rates of decomposition only during the first 3 days after a rainfall event, with 34% of the millet residue C lost as CO2 in one rainy season. Recovery of undecomposed millet residue at the end of the rainy season was related to presence or absence of termites, but not to seasonal C loss. Millet residue mulch increased soil organic C content of this sandy Alfisol in Niger. Cowpea and millet residues had a greater effect on SOM and millet yield than cowpea green manure due to their greater rate of application and slower rate of decomposition.
Anxiety Sensitivity, Emotional Avoidance, and PTSD Symptom Severity Among Crack/Cocaine Dependent Patients in Residential Treatment

High rates of co-occurring posttraumatic stress disorder (PTSD) have been found among patients receiving treatment for substance use disorders (SUD), and there is evidence that this particular co-occurrence is associated with negative SUD treatment outcomes. Thus, there is utility in establishing the role of psychological vulnerabilities related to PTSD within SUD populations, with the goal of ultimately informing targeted interventions and improving clinical outcomes. Anxiety sensitivity (AS) and emotional avoidance (EA) may be two important factors in this regard, as both have been found to demonstrate associations with posttraumatic stress in other clinical and nonclinical populations. To expand upon this literature, the current study examined the associations between AS and EA and PTSD symptom severity in a sample of traumatic event-exposed crack/cocaine dependent patients in residential SUD treatment (n = 62), as well as the extent to which EA mediated the relation between AS and PTSD symptom severity. As hypothesized, AS and EA were associated with PTSD symptom severity above and beyond the effects of gender and non-specific anxiety symptoms. However, the hypothesis that EA would mediate the relation between AS and PTSD symptom severity was only partially supported. Implications of these findings for understanding and treating co-occurring SUD-PTSD are discussed.
Influence of microstructure on quasi-static and dynamic mechanical properties of bismuth-containing lead-free solder alloys

Abstract The mechanical properties of bulk Pb-free solder alloys containing Bi have been characterized in the as-cast and aged conditions. The alloys were the commercially available Sn–3.4Ag–1.0Cu–3.3Bi and Sn–3.4Ag–4.8Bi (wt.%), which had demonstrated good reliability performance in previous circuit board-level testing programs, but have not been considered for high-volume electronic manufacturing. Room- and elevated-temperature tensile testing showed that the addition of Bi greatly reduced the loss in strength due to aging that occurs in the Sn–Ag–Cu ternary alloys. The room-temperature tensile strength of bulk SAC305 was reduced by 37% after aging at 150 °C for 336 h, but for SAC–Bi the reduction was not statistically meaningful and in SnAg–Bi the tensile strength increased. These differences are attributed to the presence of Bi and its role in solid solution strengthening and precipitation as a separate phase. The damping capacity of the alloys measured by dynamic mechanical analysis showed similar trends, with tan δ increasing in aged SAC305 but decreasing in SAC–Bi and SnAg–Bi. The reduction in damping seen in SAC–Bi and SnAg–Bi is consistent with Sn and SnPb eutectic solder, indicating that a general microstructural coarsening is responsible. The increase in damping in SAC305 suggests that the transformation of the ternary eutectic by particle coarsening leads to a continuous β-Sn matrix that contributes to damping.
The Methods and Measures of Centrography and the Spatial Dynamics of Rape

Technique known as centrography are presented in order to demonstrate their utility for describing and measuring the salient features of a spatial distribution and for facilitating temporal and comparative analyses in discerning trends and contrasting spatial distributions of crime. Centrographic techniques are applied to a 5-year data set of lone-assailant rapes classified by type of offender. The results indicate that different classes of offenders have relatively distinctive spatial distributions. Moreover, changes in the spatial distributions of offender classes, through time, are not uniform.
Relationship of time-reversal symmetry breaking to optical Kerr rotation

What symmetries must be broken in a material in order for a certain optical effect, known as Kerr rotation, to appear? Kerr rotation has been observed in some high temperature superconductors, but it was uncertain as to how to interpret these measurements and identify the material symmetries responsible for the effect. Elaborating on previous discussions (cf. e.g. PRB 90, 035135 (2014)) the author offers a proof based on the reciprocity theorem that the polar Kerr effect can be only observed if the system breaks time-reversal symmetry.
The positive predictive value of rib fractures as an indicator of nonaccidental trauma in children

Background: Rib fractures have a strong association with nonaccidental trauma (NAT) and severe trauma. The purposes of this study were to evaluate rib fractures in children to determine (1) the positive predictive value of a rib fracture in defining NAT and (2) the frequency of rib fractures as the only skeletal manifestation of NAT. Methods: We reviewed the medical records and imaging of all children with rib fractures over a 6-year period. NAT was determined by the Child Advocacy and Protection team. Results: In children younger than 3 years of age, the positive predictive value (PPV) of a rib fracture as an indicator of NAT was 95%. The positive predictive value increased to 100% once historical and clinical circumstance excluded all other causes for rib fractures. Conclusion: In this study, rib fracture(s) were the only skeletal manifestation of NAT in 29% of the children.
Identifying Local Dependence With a Score Test Statistic Based on the Bifactor Logistic Model

Local dependence (LD) refers to the violation of the local independence assumption of most item response models. Statistics that indicate LD between a pair of items on a test or questionnaire that ...
A mutant strain of Polysphondylium pallidum deficient in production of cyclic AMP.

Abstract A mutant strain (PN507) of the cellular slime mold Polysphondylium pallidum is described which: (a) is morphogenetically abnormal in stalk formation; (b) secretes unusually low quantities of cyclic AMP; (c) responds to exogenous cyclic AMP in the same manner as wild type, by differentiating stalk cells and synthesizing several specific proteins; (d) complements with other morphogenetic mutants secreting normal amounts of cyclic AMP to produce fruiting structures resembling wild type. The tentative conclusion is that the critical defect of PN507 is low production of cyclic AMP.
Probing the boundaries of the extended immunoglobulin family of recognition molecules: jumping domains, convergence and minigenes

Abstract Structural studies on proteins have placed certain molecules with related functions in extended families with a possible common ancestor. The immunoglobulin family is one such grouping: among its putative members are Thy-1, C-reactive protein, β 2 -microglobulin, and MHC class-I and class-II products. Here John Marchalonis and his colleagues discuss new computer analyses of sequence data and serological studies which argue against the inclusion of Thy-1 and C-reactive protein in the immunoglobulin family. The sequence data suggest, however, that domains may be shared by recognition molecules with different evolutionary histories and that immunoglobulin and non-immunoglobulin molecules may cross-react serologically because they have ‘minigenes' in common.
Envelope theorems for locally differentiable open-loop Stackelberg equilibria of finite horizon differential games

Abstract Envelope theorems are established for locally differentiable Stackelberg equilibria of a general class of finite horizon differential games with an open-loop information structure. It is shown that the follower's envelope results agree in form with those of any player in an open-loop Nash equilibrium, while those of the leader differ. An unanticipated conclusion is that the costate vector of the leader—but not that of the follower—corresponding to the state vector of the differential game may be legitimately interpreted as the shadow value of the state vector for time-inconsistent open-loop Stackelberg equilibria. Surprisingly, the same cannot be said for time-consistent open-loop Stackelberg equilibria.
Safety, Tolerability, QTc Evaluation, and Pharmacokinetics of Single and Multiple Doses of Enzastaurin HCl (LY317615), a Protein Kinase C-β Inhibitor, in Healthy Subjects

The safety, tolerability, and pharmacokinetics of orally administered enzastaurin were evaluated in 2 placebo-controlled, dose escalation studies in healthy subjects. In the first human dose study, single doses (2-400 mg) were evaluated, with 22 subjects receiving enzastaurin. The mean half-lives of enzastaurin and its metabolites ranged from approximately 12 to 40 hours. The longer half-life of the major circulating and pharmacologically active metabolite allowed once-a-day dosing and predicted that steady state would be achieved within 2 weeks of daily oral dosing in all subjects. In the multiple-dose study, daily doses (25-400 mg) were examined, with 24 subjects receiving at least 1 dose. The most common adverse events related to enzastaurin were headache, sleepiness, diarrhea, and nausea. No clinically significant changes in QTc intervals were observed. Overall, enzastaurin was well tolerated in healthy subjects, and the planned maximum dose was achieved in both studies.
Finite volume method for fission gas release modeling

Abstract A finite volume method is presented to analyze the fission gas release from UO 2 fuel during Light Water Reactor normal or off-normal operations, the latter being limited to Class-II type incidents. The model assumes gas diffusion inside a spherical grain under time-varying conditions. It also uses a time-varying imperfect sink condition at the grain boundary due to the accumulation of gas by irradiation-induced re-solution. The onset of gas release occurs due to the saturation of the gas amount in the grain boundaries. The problem is efficiently solved by a fast numerical technique which uses finite volumes, well-suited for application in fuel rod analyses computer codes.
Identification of PEX10, the Gene Defective in Complementation Group 7 of the Peroxisome-Biogenesis Disorders

Summary The peroxisome-biogenesis disorders (PBDs) are a group of genetically heterogeneous, lethal diseases that are characterized by neuronal, hepatic, and renal abnormalities; severe mental retardation; and, in their most severe form, death within the 1st year of life. Cells from all PBD patients exhibit decreased import of one or more classes of peroxisome matrix proteins, a phenotype shared by yeast pex mutants. We identified the human orthologue of yeast PEX10 and observed that its expression rescues peroxisomal matrix-protein import in PBD patients' fibroblasts from complementation group 7 (CG7). In addition, we detected mutations on both copies of PEX10 in two unrelated CG7 patients. A Zellweger syndrome patient, PBD100, was homozygous for a splice donor–site mutation that results in exon skipping and loss of 407 bp from the PEX10 open reading frame. A more mildly affected neonatal adrenoleukodystrophy patient was a compound heterozygote for a missense mutation in the PEX10 zinc-binding domain, H290Q, and for a nonsense mutation, R125ter. Although all three mutations attenuate PEX10 activity, the two alleles detected in the mildly affected patient, PBD052, encode partially functional PEX10 proteins. PEX10 -deficient PBD100 cells contain many peroxisomes and import peroxisomal membrane proteins but do not import peroxisomal matrix proteins, indicating that loss of PEX10 has its most pronounced effect on peroxisomal matrix-protein import.
The dynamics of copolymers in homopolymer matrices

The ability of a polymer chain to relax when it is deformed, and the ease to which this relaxation occurs, dramatically influences the macroscopic properties of the polymeric material. However, the local segmental relaxation processes in multi-component polymer systems are not well understood. The impact of the dynamics of one component on the dynamics of the other is not simply proportional to the relative amounts of each component, as one might expect. This paper discusses recent results using neutron techniques and Monte Carlo simulation that monitor the dynamic properties of a copolymer in a homopolymer matrix. In particular, the results indicate that altering either copolymer sequence distribution or copolymer composition will dramatically impact the dynamics of the copolymer that is surrounded by homopolymers. These results provide important fundamental information on the coupling of the dynamics of two components in a multi-component polymer system. This data also offer insight into the local segmental relaxation processes in multi-component polymer systems, which are not well understood and yet influence the ultimate properties of these mixtures
Student Recruitment Strategies In Undergraduate Home Economics Programs: An Exploratory Study

The survival of some college programs may depend on their ability to recruit students. The number of persons in the 18–24 year age group will steadily de cline for some time. The purpose of this study was to discover the recruitment strategies used in home economics programs and to discover if the strategies used differed by size of program, environment, or group responsible for planning recruitment. Surveys were mailed to 160 administrators of undergraduate pro grams. Results indicate that size of program, group most responsible for planning recruitment, and environment does affect the extent of use of some selected strategies. Knowing recruitment strategies and influences imposed by the organi zation may suggest alternatives to those responsible for planning recruitment.
Uncertainty Analysis of an Evolutionary Algorithm to Develop Remote Sensing Spectral Indices

The need for information extracted from remotely sensed data has increased in recent decades. To address this issue, research is being conducted to develop a complete multi-stage supervised object recognition system. The first stage of this system couples genetic programming with standard unsupervised clustering algorithms to search for the optimal preprocessing function. This manuscript addresses the quantification and the characterization of the uncertainty involved in the random creation of the first set of candidate solutions from which the algorithm begins. We used a Monte Carlo type simulation involving 800 independent realizations and then analyzed the distribution of the final results. Two independent convergence approaches were investigated: [1] convergence based solely on genetic operations (standard) and [2] convergence based on genetic operations with subsequent insertion of new genetic material (restarting). Results indicate that the introduction of new genetic material should be incorporated into the preprocessing framework to enhance convergence and to reduce variability.
A 16N GAMMA-RAY FACILITY

Abstract A practical 16N gamma-ray source is created in a medium-energy cyclotron environment. A 16N source emits 6129 and 7115 keV gamma rays. The viability of this several μCi source for detector calibration and studying detector physics is established.
Does dimethyl sulfoxide increase protein immunomarking efficiency for dispersal and predation studies

Marking biological control agents facilitates studies of dispersal and predation. This study examines the effect of a biological solvent, dimethyl sulfoxide (DMSO), on retention of immunoglobulin G (IgG) protein solutions applied to Diorhabda carinulata (Desbrochers) (Coleoptera: Chrysomelidae), an important biological control agent of saltcedar, either internally by feeding them protein-labeled foliage or externally by immersing them in a protein solution. In addition, we determined whether internally or externally marked DMSO-IgG labels could be transferred via feeding from marked D. carinulata to its predator, Perillus bioculatus (Fabricius) (Heteroptera: Pentatomidae). The presence of rabbit and chicken IgG proteins was detected by IgG-specific enzyme-linked immunosorbent assays (ELISA). DMSO-IgG treatments showed greater label retention than IgG treatments alone, and this effect was stronger for rabbit IgG than for chicken IgG. Fourteen days after marking, beetles immersed in rabbit IgG showed 100% internal retention of label, whereas beetles immersed in chicken IgG showed 65% internal retention. Immersion led to greater initial (time 0) label values, and longer label retention, than feeding beetles labeled foliage. The DMSO-IgG label was readily transferred to P. bioculatus after feeding on a single marked prey insect. This investigation shows that addition of DMSO enhances retention of IgG labels, and demonstrates that protein marking technology has potential for use in dispersal and predator–prey studies with D. carinulata. Moreover, our observation of P. bioculatus feeding on D. carinulata is, to our knowledge, a new predator–prey association for the stink bug.
Effects of Deforestation on Spatiotemporal Distributions of Precipitation in South America

AbstractThis study investigates how future deforestation in the Amazon may alter precipitation statistics in South America using a variable-resolution GCM. The model’s grid mesh is set up to cover South America and nearby oceans at mesoscale (25 km) resolution, and then to gradually coarsen and cover the rest of the world at 200-km resolution. Because of the computational efficiency of this approach, it was possible to carry out the first decadal-scale simulations of Amazon deforestation at mesoscale resolution. Unlike traditional mesoscale models, this approach does not require lateral boundary conditions. The results indicate that deforestation reduces simulated precipitation in the Amazon, but this reduction is much smaller than that seen in most previous GCM studies. Furthermore, a subcontinental redistribution of precipitation is found whereby the northwest Amazon becomes drier and the southeast Amazon becomes wetter. During most of the year, these changes are driven by changes in the mean intensity ...
Carbon atmosphere near an edge dislocation in α-iron

Abstract A model has been developed for the distribution of carbon atoms near a 1 2 [111](110) edge dislocation in α-iron. Isotropie elasticity theory, including both size and shape contributions, is used for the carbon-dislocation interaction energy, with correction factors in the core to avoid singularities. The location of octahedral sites near the dislocation is determined using the standard elastic dislocation model, and the occupation probabilities of these sites are computed using the Fermi-Dirac distribution function. Interaction between carbon atoms is neglected. This model is then used to calculate the breakaway stress of an edge dislocation from a carbon atmosphere in α-iron. The shape interaction is found to play a significant role in both the equilibrium atmosphere and the breakaway stress.
Short-term foreign exchange risk management: Zero net exposure models

Abstract By balancing the relevant end of period assets and liabilities (i.e. a zero net exposure approach to foreign exchange risk management) the multinational corporate treasurer can, conservatively, protect against parity fluctuations without requiring exchange rate forecasts. This paper presents two goal programming formulations for short-term money management and evaluates the resulting strategies (via simulation) in terms of their impact on corporate profits. A hypothetical multinational corporation with headquarters in the US and subsidiaries in Canada, West Germany, and the United Kingdom serves as the experimental unit. The results suggest that the zero net exposure approach is no better than a naive ‘dart-throwing’ approach.
Fibrinogen Stabilizes Placental-Maternal Attachment During Embryonic Development in the Mouse

In humans, maternal fibrinogen (Fg) is required to support pregnancies by maintaining hemostatic balance and stabilizing uteroplacental attachment at the fibrinoid layer found at the fetal-maternal junction. To examine relationships between low Fg levels and early fetal loss, a genetic model of afibrinogenemia was developed. Pregnant mice homozygous for a deletion of the Fg-γ chain, which results in a total Fg deficiency state (FG−/−), aborted the fetuses at the equivalent gestational stage seen in humans. Results obtained from timed matings of FG−/− mice showed that vaginal bleeding was initiated as early as embryonic day (E)6 to 7, a critical stage for maternal-fetal vascular development. The condition of afibrinogenemia retarded embryo-placental development, and consistently led to abortion and maternal death at E9.75. Lack of Fg did not alter the extent or distribution pattern of other putative factors of embryo-placental attachment, including laminin, fibronectin, and Factor XIII, indicating that the presence of fibrin(ogen) is required to confer sufficient stability at the placental-decidual interface. The results of these studies demonstrate that maternal Fg plays a critical role in maintenance of pregnancy in mice, both by supporting proper development of fetal-maternal vascular communication and stabilization of embryo implantation.
The European Trade Union Confederation at 40: integration and diversity in the European labor movement

Since its creation in 1973, the European Trade Union Confederation (ETUC) has sought to integrate Europe's diverse labor movement within a single organization for the purpose of influencing political developments at the European level. This article examines the ETUC's 40-year history, focusing on internal debates around three fundamental – and contentious – questions: who belongs in a European organization of trade unions? what objectives should the ETUC prioritize? and what tactics will be most effective to advance the interests of workers at the European level? It concludes with an assessment of how enduring internal divisions are likely to limit the ETUC's influence into the future.
In-Furrow Applications of Systemic Insecticides for Control of Mexican Bean Beetle

The duration of toxicity in snap beans produced by several systemic insecticides applied at a rate of ½-4 lb/acre in the soil at planting time was determined by bioassaying larvae of Epilachna varivestis Mulsant on new growth removed from treated plants at weekly intervals. The persistance of test insecticides appeared to be: carbofuran > phorate > aldicarb > disulfoton > dimethoate. Other tests with foliage from beans planted at the time of application of the insecticides and 1, 2, or 3 weeks later showed that some loss in toxicity occurred because of plant growth and reduced adsorption by roots, but the breakdown of the compounds in the soil caused the greater loss.
A three-dimensional transient model for flame growth and extinction in concurrent flows

A previous transient three-dimensional ignition model is extended to enable the study of both flame spread and extinction in concurrent flows. In the non-dimensional model, the flame base stabilization zone structure is resolved. Variable grid scheme is used to accelerate the numerical computation. An automatic adaptive mesh refinement scheme is developed and implemented for the moving flame stabilization zone where fuel burnout occurs. Several examples, in both forced and buoyant flows, are shown to illustrate the model capability to predict flame growth and extinction processes. The extinction modes include both quench due to heat loss in forced flow in microgravity and blowoff due to reduced Damkohler number in buoyant flow in normal gravity.
Local dynamics in multi‐local, transnational spaces of rural Mexico: Oaxacan experiences

Mexico's proximity to the United States, the two economies' increased integration, and the demand for low-cost labour in el norte, has fuelled a transnational circulation of people that is most probably self-perpetuating and is certainly firmly embedded. This investigation of local dynamics in the multi-local transnational spaces of Oaxacan households draws upon a comprehensive set of sample surveys conducted in 12 municipios in the central valleys of Oaxaca over a six-year period. We frame our Oaxaca empirical findings within two constructs developed by the authors. One is a typology of circulation behaviours differentiated by scale of interactive systems of mobility and by behavioural intentions; the other is a household migration and remittance framework that highlights the wide variations in the patterns of investment of remittances by recipient households. Extending these frameworks, we use village- and family-level evidence to demonstrate the crucial significance of local contexts for determining household strategies of migration and remittance investment. What is most apparent from our Oaxacan biographies is, firstly, the wide range of experiences that are present both within and between the various communities; secondly, the strategic use of local circuit moves in concert with national and international (or transnational) sojourns; and thirdly, the various positive and negative impacts of migration and remittance investment that range from self-aggrandisement to community investment. Our analysis concludes that local space is an essential contextual anchor, and the evolving nature of household migration decision-making is in large part determined, or at least significantly influenced, by the spatial nature of the social linkages between people, their households/families, and their local, regional, national and transnational contexts. Copyright © 2003 John Wiley & Sons, Ltd.
Modern Natural Products Drug Discovery and its Relevance to Biodiversity Conservation

Natural products continue to provide a diverse and unique source of bioactive lead compounds for drug discovery, but maintaining their continued eminence as source compounds is challenging in the face of the changing face of the pharmaceutical industry and the changing nature of biodiversity prospecting brought about by the Convention on Biological Diversity. This review provides an overview of some of these challenges and suggests ways in which they can be addressed so that natural products research can remain a viable and productive route to drug discovery. Results from International Cooperative Biodiversity Groups (ICBGs) working in Madagascar, Panama, and Suriname are used as examples of what can be achieved when biodiversity conservation is linked to drug discovery.
Price–cost margins and imports in an oligopolistic market

Abstract In a recent letter in this journal Urata (1979) found an unexpected, positive, and significant association between price–cost margins and import to domestic shipment ratio for the U.S. textile and apparel industries. In the present letter a theoretical explanation for this phenomenon is presented by extending a conjectural variation oligopoly model.
Site-Directed Spin Labeling Reveals Pentameric Ligand-Gated Ion Channel Gating Motions

Pentameric ligand-gated ion channels (pLGICs) are neurotransmitter-activated receptors that mediate fast synaptic transmission. In pLGICs, binding of agonist to the extracellular domain triggers a structural rearrangement that leads to the opening of an ion-conducting pore in the transmembrane domain and, in the continued presence of neurotransmitter, the channels desensitize (close). The flexible loops in each subunit that connect the extracellular binding domain (loops 2, 7, and 9) to the transmembrane channel domain (M2-M3 loop) are essential for coupling ligand binding to channel gating. Comparing the crystal structures of two bacterial pLGIC homologues, ELIC and the proton-activated GLIC, suggests channel gating is associated with rearrangements in these loops, but whether these motions accurately predict the motions in functional lipid-embedded pLGICs is unknown. Here, using site-directed spin labeling (SDSL) electron paramagnetic resonance (EPR) spectroscopy and functional GLIC channels reconstituted into liposomes, we examined if, and how far, the loops at the ECD/TMD gating interface move during proton-dependent gating transitions from the resting to desensitized state. Loop 9 moves ∼9 A inward toward the channel lumen in response to proton-induced desensitization. Loop 9 motions were not observed when GLIC was in detergent micelles, suggesting detergent solubilization traps the protein in a nonactivatable state and lipids are required for functional gating transitions. Proton-induced desensitization immobilizes loop 2 with little change in position. Proton-induced motion of the M2-M3 loop was not observed, suggesting its conformation is nearly identical in closed and desensitized states. Our experimentally derived distance measurements of spin-labeled GLIC suggest ELIC is not a good model for the functional resting state of GLIC, and that the crystal structure of GLIC does not correspond to a desensitized state. These findings advance our understanding of the molecular mechanisms underlying pLGIC gating.
Estimating Risk Premiums of Individual Hedge Funds

This paper introduces a methodology for estimating the risk premiums earned by individual hedge funds and provides results of the distribution of risk premiums both within and between various hedge fund strategies. Results indicate that the majority of funds earn average excess return greater than the expected excess return based on the estimated total average risk premium. Although there is wide variation of the estimated risk premiums within each strategy, much of the variation is concentrated in the bottom and top-performing funds.
Factors affecting urban-to-rural migration.

PIP: This study is concerned with the household characteristics of those involved in the population turnaround from metropolitan to nonmetropolitan areas in the United States. Its primary objective is to examine empirically the factors affecting the population turnaround and to provide some additional insights into the general directions of this migration trend. Data for the study are taken from a longitudinal nationwide sample survey conducted by the Institute for Social Research at the University of Michigan and involving approximately 6,000 families interviewed annually since 1968.
A structural approach to women's hometime and experience-earnings profiles: Maternity leave and public policy

The differential availability of maternity leave benefits is shown to be an important factor in the earnings attainment process of women. Interaction effects with this job characteristic are found for experience, occupational status, and crowding. The human capital model's explanation of the relationship between women's hometime, women's job choice, and public policy is critically examined. The results indicate that the provision of adequate child care needs to be coupled with parental leave policies if women are to make significant gains in earnings from reducing their time spent at home.