cssi/SciSciGPT-SciSciNet huggingface dataset:
THERMAL BUCKLING AND POSTBUCKLING OF SYMMETRICALLY LAMINATED COMPOSITE PLATES

The thermal buckling and postbuckling response of symmetrically laminated composite plates are discussed. Using variational methods in conjunction with a Rayleigh-Ritz formulation, thermal buckling and postbuckling are investigated for two laminates, a (+/- 45/0/90) and a (+/- 45/02), under two different simple support conditions, fixed and sliding. These laminates are subjected to the condition of a uniform temperature change. The effects of the principal material axis not being aligned with the edges of the plate, referred to here as material axis skewing, are also investigated. Although differences between buckling temperatures for the two support conditions were small, support conditions can have a large influence on thermal postbuckling response. In general, plates with fixed simple supports deflect more than plates with sliding simple supports. In addition, support conditions can influence modal interaction. Skewing of the material axis decreases the buckling temperatures of both laminates and, like fixed support conditions, causes increased postbuckling deflections. Skewing also influences modal interaction.
Reply to comment on ‘Assessing the implications of K isotope cosmochemistry for evaporation in the preplanetary solar nebula’ by E. Young

Abstract Humayun offers several criticisms of the analysis of K isotope cosmochemistry by Young. Although Humayun’s comments provide a useful description of diffusion-limited evaporation, they are not relevant to the mechanism for volatile element depletion put forward by Young. The mechanism described by Young is evaporation of a ‘heterogeneous mixture of crystalline solids’. In presenting his model Young made four essential assertions: (1) the truism that the more volatile minerals are composed of the more volatile elements; (2) most rock-forming elements likely entered the early solar nebula in solid form; (3) dust in the early solar system was unlikely to be uniform in composition on the scale of individual grains; and (4) partial evaporation of crystalline solids has little effect on the isotopic composition of the residues. Humayun expresses concerns about the relevance of the last assertion but does so without the vital context provided by assertions (1)–(3). There are two underpinnings to Humayun’s comments. First is the tacit assumption that dust in the early solar system was composed of grains with identical chemical compositions, effectively ignoring Young’s proposed mechanism for volatile element depletion. Second is the notion that the mass fractions used by Young are extensive parameters that have little to do with the original paper by Humayun and Clayton. The first issue of whether or not solids in the early solar system were uniform in composition at the grain scale is open for debate. Young’s model assumes that the grains were not all identical in composition. The second issue of whether or not Humayun and Clayton and Young used comparable methods for depicting depletion of K in solar system bodies should not be a matter for debate because the normalized concentration ratios used by Humayun and Clayton are equivalent to the intensive mass fractions used by Young, as shown again below.
One-step-ahead kinematic compressive sensing

A large portion of work on compressive sampling and sensing has focused on reconstructions from a given measurement set. When the individual samples are expensive and optional, as is the case with autonomous agents operating in a physical domain and under specific energy limits, the CS problem takes on a new aspect because the projection is column-sparse, and the number of samples is not necessarily large. As a result, random sampling may no longer be the best tactic. The underlying incoherence properties in l 0 reconstruction, however, can still motivate the purposeful design of samples in planning for CS with one or more agents; we develop here a greedy and computationally tractable sampling rule that will improve errors relative to random points. Several example cases illustrate that the approach is effective and robust.
Combining History and Historical Demography to Understand a Nineteenth Century City

Most major North American cities have their origins in the nineteenth century, combining internal migration with immigration from abroad to provide the labor force for a growing urban economy. Migr...
Cobalt metal inhalation studies on miniature swine.

Cobalt is considered to be the chief component in the tungsten carbide mixture responsible for hard-metal disease. An animal inhalation study was undertaken simulating conditions under which these workers in the tungsten carbide industry are exposed to cobalt. In this semichronic study, miniature swine were exposed to an inhalation of pure cobalt metal powder at concentrations of 0.1 mg/m3 (present TLV) and 1.0 mg/m3. At periodic intervals, the following studies were performed: pulmonary function tests, electrocardiograms, x-ray examinations, blood and urine tests, electron microscopy, and light microscopic pathology. Early detection of pulmonary disease is apparent from the pulmonary function tests showing a mark decrease in lung compliance, and from electron microscopy showing an increase in the amount of septal collagen. This study demonstrates that the present TLV of 0.1 mg/m3 for cobalt seems to be too high, even at this relatively brief duration of exposure.
A simple and sensitive assay for 9-hydroxyprostaglandin dehydrogenase

The tritium recovery assay of 9-hydroxyprostaglandin dehydrogenase [Pace-Asciak, C. (1975) J. Biol. Chem.250, 2789] has been modified to ensure its applicability to both crude and purified enzyme preparations. The stereospecificity of NAD+-dependent 9-hydroxyprostaglandin dehydrogenase with respect to NAD+ was determined first and found to be A-side specific. Based on the stereospecificity of the enzyme, a simple and sensitive assay method for 9-hydroxyprostaglandin dehydrogenase has been developed. The assay is able to detect picomole quantities of substrate conversion. When 15-keto-13,14-dihydro-[9β-3H]PGF2α is employed as substrate, the tritium label of the tritiated prostaglandin is effected to transfer to lactate stereospecifically by coupling 9-hydroxyprostaglandin dehydrogenase with a saturating level of lactate dehydrogenase. The amount of prostaglandin oxidized is quantitated by the radioactivity of the labeled lactate produced, which is separated from labeled prostaglandin by charcoal precipitation. Simultaneous assays with the current tritium-release and thin-layer chromatography methods indicated excellent correlation. Using this method we have found that rat kidney possesses the highest enzyme activity among those tissues examined. Rat kidney enzyme activity is linear for the first 10 min it is studied and is nonlinear with increasing amounts of crude enzyme extract, indicating the possible presence of endogenous inhibitor(s). The apparent Km for 15-keto-13,14-dihydro-PGF2α is 0.66 μm. The enzyme is activated by imipramine, inhibited by indomethacin, but not affected by furosemide and ethacrynic acid. These results confirm previous findings reported in the literature.
Nitrogen isotope ratios in estuarine biota collected along a nutrient gradient in Narragansett Bay, Rhode Island, USA.

Abstract Stable nitrogen isotope ratios were used to study the incorporation of anthropogenically-derived nitrogen into the food webs of salt marsh systems along a contamination gradient in Narragansett Bay. Nitrogen isotope ratios ( δ 15 N) were measured in six estuarine species collected from three marshes along this gradient, monthly from June to October between 1997 and 1999. A significant decrease in δ 15 N was found with distance along the estuary for four of the six species. Significant differences were found among monthly isotope ratios for some species. Nitrogen isotope ratios in sea lettuce ( Ulva lactuca ) increased during the summer season with highest δ 15 N values measured during September and October. This trend was most pronounced at the station receiving the highest nutrient inputs. Elevated δ 15 N values at this station appeared to correlate with seawater ammonia/nitrate concentration ratios. The temporal variations in δ 15 N suggest that care should be taken in species selection and the design of sampling schemes of studies using δ 15 N for monitoring anthropogenic nutrients in aquatic systems. Sampling programs designed to determine long-term trends should consider species that do not show rapid fluctuations in isotope ratios. The mud snail, Nassarius obsoletus , responded this way in the present study. Studies designed to measure short-term changes should include species such as U. lactuca , which rapidly respond to isotope changes. The results from this study also help to establish a baseline for nitrogen isotope values in Narragansett Bay. This information can be used to monitor future trends in nitrogen inputs to this estuary.
1038 PEDIATRIC NOCARDIOSIS

Nocardial infections are considered rare in children, occurring mainly as pulmonary disease in immuno-compromised hosts(CH), with N. asteroides the predominant species. A review of our experience over a five year period(′75-′80) suggests a different clinical spectrum. A summary of the clinical data is shown below: Of special interest was the frequency of N. brasiliensis infection, formerly considered very rare in the U.S. and usually manifest as mycetoma. In contrast, all 5 patients were previously healthy children who developed acute subcutaneous abscess(2 submandibular, 1 scalp, 1 axilla, 1 hand & elbow); 2 had a primary pustular lesion with regional suppurative adenitis; 3 had a history of trauma. Gram stain of purulent material showed gram-positive branching filaments in 2 of 3. Therapy(drainage and/or antibiotics) was successful in all 5. We conclude that nocardiosis, particularly that due to N. brasiliensis, is more common in normal children than previously reported and should be considered in the differential diagnosis of subcutaneous abscess, especially if there is a history of trauma.
The acute effect of exercise and nutrition on respiratory exchange ratio in women

Methods Twenty recreationally active women (Mean ± SD; age 24.6 ± 3.9 yrs; height 164.4 ± 6.6 cm; weight 62.7 ± 6.6 kg; %fat 28.2 ± 4.8 %) participated in this randomized crossover, double-blind study. After preliminary body composition and maximal strength testing, each participant completed six exercise sessions, consisting of three exercise modalities: aerobic endurance exercise (AEE; 30 min, 50% heart rate reserve), high-intensity interval running (HIIT; 10 x 1min on: 1min off, 90% HRR), and high-intensity resistance training (HIRT; 6 exercises: 3 sets, 20 sec rest), and two acute nutritional interventions: 25 grams of CHO (maltodextrin) and PRO (whey protein isolate). Salivary samples were collected before each exercise session to determine estrogen. RER was analyzed via indirect calorimetry (Parvomedics TrueOne 2400) at: baseline, immediately post (IP), 30 minutes (30min) post, and 60 minutes (60min) post-exercise. Subjects were seated and connected to the metabolic cart by a tube for 15 minutes at each time point. A mixed level model [modality (AEE vs. HIIT vs. HIRT) × treatment (CHO vs. PRO) × time (base vs. IP vs. 30min vs. 60min)] covaried for estrogen was used to evaluate RER. Consent to publish the results was obtained from all participants. Results Significant two-way interactions existed between modality and time (p<0.0001) and time and treatment (p<0.0001). Significant modality differences existed between HIIT and AEE (p<0.0001), HIIT and HIRT (p<0.0001), and AEE and HIRT (p=0.0024). RER was significantly higher from HIIT than AEE and HIRT IP exercise (p<0.0001), and significantly lower from HIIT 30min and 60min post exercise (p<0.0001-p=0.0020) than AEE. RER was significantly lower 30min (p=0.0169), but not 60min post (p=0.3603) HIIT vs. HIRT. No significant differences existed between HIRT and AEE IP exercise (p=0.3370); RER was significantly lower for HIRT than AEE 30min and 60min post exercise (p=0.0004-0.0265). For time and treatment, RER was not significantly different between CHO and PRO IP exercise (p=0.1150), but was significantly lower for PRO 30min and 60min post (p<0.0001p=0.0012).
Quantitation of Cell Wall Growth Suggests Feedback Mechanisms that Robustly Build Rod-Like Bacteria

In bacteria, a host of enzymes regulates the reproducible and robust construction of the cell wall, whose mechanical integrity is crucial for viability under osmotic stress. Antibiotics that target these enzymes disrupt cell wall construction, ultimately leading to mechanical failure of the cell. Our work explores the physical mechanisms of cell growth and death, as a guide to understanding antibiotic mechanisms that disrupt mechanical properties of the cell. We use a combination of cell wall fluorescent labeling, high resolution time-lapse microscopy, and computational image processing to characterize where, and with what dynamics, cell wall and outer membrane growth occurs. When cell-shape analysis is combined biophysical simulations of growth, our data strongly suggest that dynamic localization of the bacterial MreB cytoskeleton is part of a curvature sensing and growth feedback mechanism that orchestrates heterogeneous growth to maintain rod-like shape and regulate mechanical stress. Analysis of MreB and cell-surface marker fluorescence indicates that the cytoskeleton is present at sites of active growth and that chemical depolymerization of the cytoskeleton causes homogenous, unstructured growth and eventual cell death by rupture. Quantitative tracking of growth is an effective method for characterizing cell wall mechanical failure, and these techniques pave the way for studying the detailed dynamics of growth-associated proteins and their disturbance by antibiotics.
An assessment of agonist/antagonist effects of tamoxifen in the female mouse brain

Ovariectomized CFW mice were treated with tamoxifen (TAM) alone or in combination with estradiol benzoate (EB) to determine its ability to promote/block lordotic behavior and the induction of hypothalamic progestin receptors (PR). Across a range of doses, TAM plus progesterone treatment did not activate female sexual behavior. When given with EB, TAM suppressed lordotic behavior in a dose-dependent fashion. TAM did not induce PR when given alone and it completely blocked the ability of EB to induce PR. It therefore appears that for these responses TAM functioned as a pure antagonist in the female mouse brain, although the degree of its antiestrogenicity varied with the response under consideration. A potential mechanism mediating this differential effectiveness is discussed.
Assimilation of drifter observations in primitive equation models of midlatitude ocean circulation

[1] Motivated by increases in the realism of OGCMs and the number of drifting buoys in the ocean observing system, a new Lagrangian assimilation technique is implemented in an idealized, reduced-gravity configuration of the layered primitive equation model MICOM. Using an extensive set of twin experiments, the effectiveness of the Lagrangian observation operator and of a dynamical balancing technique for corrected model variables, which is based on geostrophy and mass conservation, are explored in comparison to a conventional Pseudo-Lagrangian observation operator and an implementation of the Kalman filter method. The results clearly illustrate that the Lagrangian observation operator is superior to the Pseudo-Lagrangian in the parameter range that is relevant for typical oceanic drifter observations, and that the simple dynamical balancing technique works well for midlatitude ocean circulation. INDEX TERMS: 4263 Oceanography: General: Ocean prediction; 4255 Oceanography: General: Numerical modeling; 4594 Oceanography: Physical: Instruments and techniques; 4572 Oceanography: Physical: Upper ocean processes; KEYWORDS: Lagrangian data assimilation, data assimilation, drifter assimilation, ocean prediction, ocean modeling
Fluorescence lifetime studies with staphylococcal nuclease and its site-directed mutant. Test of the hypothesis that proline isomerism is the basis for nonexponential decays

Using frequency domain methods, the fluorescence decay of Trp-140 in staphylococcal nuclease and its site-directed mutant (Pro-117----Gly) has been examined. Based on nuclear magnetic resonance (NMR) studies (Evans, P. A., C. M. Dobson, R. A. Kautz, G. Hatfull, and R. O. Fox. 1987. Nature [Lond.]. 329:266–268), it is believed that nuclease exists in two macroscopic, native conformations and that the slow interconversion of these conformations is controlled by the cis----trans isomerization of Pro-117. The above mutant shows only one native conformation in NMR experiments. To test the hypothesis that the biexponential fluorescence decay of Trp-140 of nuclease can also be related to the existence of these conformational states of the protein, we have compared the decay patterns of the wild type and mutant. Essentially no difference was observed, which indicates that there is some other basis for the nonexponential decay of Trp-140. We have used global nonlinear least squares analysis to link the fit of data at several temperatures.
The Financial Burden of Medical Spending Estimates and Implications for Evaluating the Impact of ACA Reforms

This article uses the 2013 Current Population Survey Annual Social and Economic Supplement to estimate the financial burden of medical out-of-pocket costs by comparing medical out-of-pocket expenditures to income. This measure is important for evaluating the magnitude of burden, better understanding who bears it, and establishing a baseline to assess the impact of the Patient Protection and Affordable Care Act. We examine the distribution of burden and the incidence of high burden across all families and by individuals' health insurance status and demographic and socioeconomic characteristics. We look more closely at one group vulnerable to having high burden: those younger than age 65 with incomes between 138% and 200% of the federal poverty line. We find that 18.5% of these individuals have incomes below the threshold of expansion Medicaid eligibility after accounting for non-over-the-counter medical expenses and examine the characteristics associated with being classified below this threshold.
Effectiveness versus efficacy: more than a debate over language.

As the physical therapy profession continues the paradigm shift toward evidence-based practice, it becomes increasingly important for therapists to base clinical decisions on the best available evidence. Defining the best available evidence, however, may not be as straightforward as we assume, and will inevitably depend in part upon the perspective and values of the individual making the judgment. To some, the best evidence may be viewed as research that minimizes bias to the greatest extent possible, while others may prioritize research that is deemed most pertinent to clinical practice. The evidence most highly valued and ultimately judged to be the best may differ based on which perspective predominates. One issue that highlights the importance of perspective in judging the evidence is the difference between efficacy and effectiveness approaches to research. These terms are frequently assumed to be synonyms and are often used incorrectly in the literature. There is actually a meaningful distinction bet...
Anatomic features of the optic disc and risk of progression in ocular hypertension.

ABSTRACT We evaluated characteristics of the optic disc in ocular hypertensive patients which might portend future glaucomatous damage. We included in this study 12 patients with an intraocular pressure > 21 mmHg who on follow-up showed signs of optic nerve head damage. Each of these patients were matched to an ocular hypertensive patient who remained stable for > 5 years. This study found that neither optic disc, neural rim or peripapillary halo areas, vein or artery diameter over non-atrophied or atrophied retinal areas, differed significantly between groups (p > 0.05, Wilcoxon signed rank test). However, peripapillary atrophy was greater in patients who showed signs of glaucomatous disc damage (1.757 ± 0.36 mm2, p = 0.02, Wilcoxon signed rank test) compared to stable patients (1.064 ± 0.79 mm2), although this finding was not significant after the Bonferroni correction. Patients with < 0.6 mm2 area of peripapillary atrophy (n = 6), however, did not suffer damage. This study suggests that a relationship between the extent of peripapillary atrophy and the chance of developing optic disc damage in patients with ocular hypertension deserves further study.
A reliability analysis of Mechanical Turk data

MTurk workers completed several forms of the same self-report scale.Generally, score reliability was lower for MTurk workers than the normative sample.Survey length and payment did not affect reliability.However, more reliable scores were provided when workers verified attentiveness. Amazon's Mechanical Turk (MTurk) provides researchers with access to a diverse set of people who can serve as research participants, making the process of data collection a streamlined and cost-effective one. While a small number of studies are often cited to support the use of this methodology, there remains a need for additional analyses of the quality of the research data. In the present study, MTurk-based responses for a personality scale were found to be significantly less reliable than scores previously reported for a community sample. While score reliability was not affected by the length of the survey or the payment rates, the presence of an item asking respondents to affirm that they were attentive and honest was associated with more reliable responses. Best practices for MTurk-based research and continuing research needs are addressed.
How do commonly performed lymphadenectomy templates influence bladder cancer nodal stage

Purpose: Determining pathological nodal stage in patients with bladder cancer is important for prognosis. We determined how the extent of lymphadenectomy and the lymph node count influence accurate nodal staging.Materials and Methods: The study included 120 patients who underwent at least extended lymphadenectomy at radical cystectomy. Different anatomical templates for lymphadenectomy were evaluated for nodal staging accuracy. The cumulative percent was plotted to determine a lymph node count that confidently identified node positive cases.Results: The mean ± SD total lymph node count in the study population was 36.9 ± 14.8 at extended lymphadenectomy. Of the patients 36 (30%) had lymph node metastasis, including 14 (39%) with metastasis involving the common iliac and/or presacral lymph nodes. Limited, standard and extended lymphadenectomy accurately identified 75%, 88.9% and 100% of node positive cases, respectively. Removing 23 and 27 lymph nodes provided 80% and 90% confidence, respectively, that a ca...
Attempt to Date Early South African Hominids by Using Fission Tracks in Calcite

Calcite crystals extracted from marrow cavities of bones found in hominid-bearing breccias from Makapansgat and Swartkrans were studied for fossil tracks. The absence of the expected numbers of tracks in these and in calcites from Beds I and II, Olduvai Gorge, combined with the results of laboratory heating experiments, indicates that track annealing has occurred at ambient temperatures and precludes the widespread use of calcite for fission track dating.
Student civility in nursing programs: A national survey

Abstract A survey of 611 nursing programs was performed to determine the extent to which certain problematic student behaviors existed in schools of nursing, and how they were being addressed. Participants were also asked about specific behaviors of current students compared with those of 5 years ago. Of the 611 surveys sent to program directors, 2 were undeliverable and 409 responded for a response rate of 67 per cent. The majority of respondents (48.8 per cent) were from associate degree programs, followed by baccalaureate degree (43.9 per cent), and diploma programs (7 per cent). Three disruptive behaviors were identified by all respondents: inattentiveness in class, attendance problems, and lateness. Objectionable physical contact between students and instructors were identified by 24.8 per cent, and verbal abuse toward instructors in the clinical setting by 42.8 per cent. Demographic variables examined in terms of their relationship to the behaviors included type of program, nursing program size, size of the parent institution, geographic region, location of program, and sponsorship of program. Administrators in different types of educational programs and from various geographic locations reported problematic student behaviors with high frequency. Identifying strategies for handling disruptive behaviors and assistance in implementing them is recommended along with a national forum to discuss the issue. J Prof Nurs 17:81-86, 2001. Copyright © 2001 by W.B. Saunders Company
Estimation of parameters involved in high angle-of-attack aerodynamic theory using spin flight test data

The difficulty in applying parameter estimation techniques to spinning airplanes is due in part to the unwieldy number of possible combinations of terms in the equations of motion, when the model structure is unknown. The combination of high angle of attack and high rotation rate results in aerodynamic functions which are quite complex. For wing dominated configurations it is advantageous to use aerodynamic theory to generate the model structure. In this way, the number of unknown parameters is reduced and the model accuracy may be increased. Under conditions for which the theory is inadequate, however, model accuracy may be reduced. Strip theory, for example, is incapable of predicting autorotative rolling moments indicated by wind tunnel tests at angles of attack exceeding 40 degrees. An improved aerodynamic theory would be necessary to successfully apply the technique advanced for such regions.
A portable neuromuscular function assessment for studying recovery from hip fracture.

Abstract Objective: To determinethe reliability of applicability of a portable, performance-based assessment of balance and gait in characterizing recovery after hip fracture in elderly persons. Design: The assessment was developed as part of a prospective, observational study of hip fracture recovery among elderly persons. Reliability was assessed in 24 subjects by administering the tasks twice within 1 week. Setting: In-home assessments were performed on community-dwelling elderly. Patients: Randomly selected subset of hip fracture patients, 65 years and older, admitted to 1 of 8 Baltimore hospitals between January 1990 and June 1991. Twenty-four patients were asked to repeat the gait and balance assessment at the 6-month follow-up visit. Main Outcome Measures: The evaluation included: (1) sitting balance, (2) arising from an armless chair, (3) standing balance, eyes open and closed, (4) one leg standing balance, (5) sitting down, (6) gait, and (7) range of motion in the knee and hip. Results: The assessment took 15 to 20 minutes to complete and was feasible to perform for recent hip fracture patients, except for single leg standing. Interrater reliability was good for most tasks, with agreement between evaluators being 74% to 100% for tasks involving standing balance, chair rise, gait, and range of motion; kappas=0.4 to 0.9. Single leg standing, knee extension, and balance while sitting were the least reliable tasks; 59% to 73% agreement, kappas=0.1 to 0.4. Conclusions: We conclude that this instrument is a reliable measure of physical ability that will provide a clear indication of mobility impairment in patients recovering from a hip fracture. This instrument should prove usefl in assessing patients with lower extremity difficulties.
Intestinal ion transport and the pathophysiology of diarrhea

Worldwide, diarrhea claims several million lives annually, mostly those of infants. Poverty, crowding, and contaminated water supplies all contribute. Almost all of these deaths could have been prevented with adequate fluid replacement. Although its incidence is much lower in the more affluent nations, diarrhea remains one of the two most common reasons for visits to pediatric emergency departments and is also common among the institutionalized elderly. Chronic diarrheas, while less common, often present diagnostic dilemmas and can be difficult to manage. This article will begin by reviewing the relevant physiology; then, with that as context, it will consider pathophysiology, both general aspects and specific diarrheal syndromes. Finally, rationales for management will be briefly considered. The review is amply referenced with some of the references listed at the end of the article and some at the JCI website (http://www.jci.org/cgi/content/full/111/7/931/DC1).
Practical Approaches to Pharmacologic Management of Pain in Older Adults With Cancer

PURPOSE/OBJECTIVES To identify appropriate strategies for pharmacotherapeutic agents in the management of pain in older adults with cancer. DATA SOURCES PubMed literature searches, personal reference collection, and clinical experience. DATA SYNTHESIS To make good decisions about pain management when developing treatment plans for older adults, healthcare providers should focus on the pharmacokinetic and pharmacodynamic properties of drugs in the context of the physiologic changes that occur with aging. CONCLUSIONS Unrelieved pain can have a detrimental effect on older adults; conversely, overmedicating can lead to an increased risk of adverse events. With advancing age, physiologic changes alter the pharmacokinetic and pharmacodynamic properties of drugs by reducing their absorption, changing their distribution, and modifying their metabolism and elimination. Also, common comorbidities increase the risk of pharmacologic toxicity and narrow the therapeutic window. In addition, polypharmacy-an issue more common in older adults-increases the complexity of prescribing and risk of adverse events. Consequently, older adults require individualization of their pharmacotherapies. Healthcare providers should consider carefully the risks and benefits of nonsteroidal anti-inflammatory drugs, opioids, and adjuvants before initiating an analgesic trial. The 2009 guidelines published by the American Geriatrics Society described several key principles for prescribing analgesics to older adults and offered specific recommendations and caveats for each drug class. IMPLICATIONS FOR NURSING Current guidelines support appropriate management of cancer pain in older adults with specific recommendations for each class of analgesics as well as general prescribing principles.
Spinal canal narrowing during simulated frontal impact

Between 23 and 70% of occupants involved in frontal impacts sustain cervical spine injuries, many with neurological involvement. It has been hypothesized that cervical spinal cord compression and injury may explain the variable neurological profile described by frontal impact victims. The goals of the present study, using a biofidelic whole cervical spine model with muscle force replication, were to quantify canal pinch diameter (CPD) narrowing during frontal impact and to evaluate the potential for cord compression. The biofidelic model and a sled apparatus were used to simulate frontal impacts at 4, 6, 8, and 10 g horizontal accelerations of the T1 vertebra. The CPD was measured in the intact specimen in the neutral posture (neutral posture CPD), under static sagittal pure moments of 1.5 Nm (pre-impact CPD), during dynamic frontal impact (dynamic impact CPD), and again under static pure moments following each impact (post-impact CPD). Frontal impact caused significant (P<0.05) dynamic CPD narrowing at C0-dens, C2-C3, and C6-C7. The narrowest dynamic CPD was observed at C0-dens during the 10 g impact and was 25.9% narrower than the corresponding neutral posture CPD. Interpretation of the present results indicate that the neurological symptomatology reported by frontal impact victims is most likely not due to cervical spinal cord compression. Cord compression due to residual spinal instability is also not likely.
Siegel Modular Forms, L-Functions, and Satake Parameters

Abstract In this paper we take a first step towards a multiplicity-one result for Siegel modular forms on Spn( Z ). We study two L-functions associated to Siegel modular forms, the spinor zeta function in genus 2 and the standard zeta function for arbitrary genus. Both the spinor and standard zeta function are defined as products over all primes and we show that the factors for almost all primes determine the L-function. The study of these zeta functions naturally leads to the study of an invariant related to Siegel modular forms, Satake p-parameters. Our result equivalently states that for a simultaneous Hecke eigenform, the Satake parameters for almost all primes determine the Satake parameters for all primes up to an occasional variation in sign.
Product improvement and leadership in differentiated markets

This paper examines the persistence of market leadership when firms invest nonexclusively in product-improving R&D prior to competing in a differentiated Bertrand market. The analysis establishes that whether a leader maintains its position depends on the nature and extent of differentiation. While a leader in a horizontally differentiated market always becomes increasingly dominant as a result of its investment, there exist equilibria in which a leader in a vertically differentiated market loses its position.
Effect of carcinogens and related compounds on the semiconductive properties of protein.

The d.c. electrical conductivity of solid gels of bovine plasma albumin, under high vacuum, shows a semiconductive behavior which is sensitive to small amounts of complexed carcinogens and related compounds. The effect of these compounds on the electrical properties of the protein provides evidence of an interaction which may be related to the carcinogenic activity.
Construction and performance of a rapid scan monochromator for multiwavelength fluorimetry.

Abstract A rapid scan monochromator was constructed for multiwavelength illumination of biological samples. A light weight holographic grating (2400 grooves/mm) was driven by a rapid stepper motor with 0.014° angular resolution in an f 4 monochromator. Angular velocity and acceleration kinetics were optimized to minimize the time for grating rotation and stabilization. The times required for shifting output wavelengths by 20, 100, and 300 nm were 6, 7, and 9 ms, respectively. Wavelength selection and dwell times were software controlled and reproducible over extended data collections. Instrument utility was demonstrated by measurement of intracellular calcium in fura-2-labeled Chinese hamster lung fibroblasts at excitation wavelengths of 340, 360, and 380 nm. Compared to available filter wheel and chopper devices, the rapid scan monochromator has advantages of rapid and software-selectable wavelength control, excellent optical alignment, small size, and low cost. Applications of this device include illumination optics for multiwavelength microfluorimetry and scanning absorption spectroscopy, and detection optics for microspectroscopy.
Complications of antiobesity surgery

Bariatric surgery is an effective long-term treatment for morbid obesity. This Review discusses the indications for bariatric surgery and the early and late complications associated with the two most commonly performed bariatric procedures–laparoscopic gastric bypass and laparoscopic adjustable silicone gastric banding. Laparoscopic biliopancreatic diversion and laparoscopic sleeve gastrectomy are also briefly discussed. Bariatric surgery is an effective long-term treatment for patients who suffer from morbid obesity, the incidence of which is increasing in North America. Laparoscopic gastric bypass and laparoscopic adjustable gastric band placement are the two commonly performed bariatric procedures. This article discusses the indications for bariatric surgery and the early and late complications associated with these two procedures. Laparoscopic biliopancreatic diversion and laparoscopic sleeve gastrectomy are also briefly discussed.
SU‐EE‐A1‐05: Trade‐Off between Treatment Plan Quality and Beam‐On‐Time in IMRT Using Direct Aperture Optimization

Purpose: Beam‐on‐time is an important aspect of IMRT treatment efficiency, but optimization of this is usually postponed until the leaf sequencing phase of treatment planning. However, there exists a trade‐off between treatment plan quality and beam‐on‐time. The aim of this study is to incorporate the beam‐on‐time into a direct aperture optimization model to explicitly quantify that trade‐off. Method and Material: A direct aperture optimization problem is formulated that includes a composite measure of treatment plan quality as well as a penalty for beam‐on‐time. An efficient method is developed to then obtain all treatment plans on the entire corresponding Pareto‐efficient frontier. Starting with a very large beam‐on‐time penalty for which it is optimal not to treat, the beam‐on‐time penalty is reduced while simultaneously adding high‐quality deliverable apertures while ensuring that the treatment plan remains Pareto efficient. The method can account for several MLC delivery constraints (row‐convexity, interdigitation, connectedness, jaws‐only). Using the set of Pareto‐optimal treatment plans, gains in different measures of treatment plan quality that can be obtained when beam‐on‐time is increased are quantified. The analysis also identifies the range of beam‐on‐times for which a clinically acceptable treatment plan is obtained Results: For a set of ten clinical head‐and‐neck cases, the trade‐offs between the treatment plan quality and beam‐on‐time are quantified. The impact of allowing for longer beam‐on‐times on the DVH criteria was investigated. Conclusion: This work provides a direct aperture optimization model that explicitly incorporates beam‐on‐time. The model allows for studying the effect of beam‐on‐time on the treatment plan quality.
Synthesis, structure, and hydroamination kinetics of (2,2′- diaryldipyrrolylmethane)- and bis(2-arylpyrrolyl)titanium complexes

The trifluoroacetic acid catalyzed reaction of acetone and 2-arylpyrroles results in the formation of 2,9-diaryl-5,5-dimethyldipyrrolylmethanes. Ligands bearing 3,5-(CF3)2C6H3 (H2dmpm3,5-CF3) and mesityl (H2dmpmmes) arenes were prepared in 72% and 68% yields using this procedure. The new dipyrrolylmethanes react with Ti(NMe2)4 to form Ti(NMe2)2(dmpm3,5-CF3) and Ti(NMe2)2(dmpmmes) in 92% and 30% yields, respectively. The solid-state structures of these complexes are quite similar to that of the sterically smaller 5,5-dimethyldipyrrolylmethane complex Ti(NMe2)2(dmpm) with one η5- and one η1-pyrrolyl; however, the substituted derivatives display much lower barriers to pyrrolyl conformational exchange, as judged by VT 1H NMR spectroscopy. Also synthesized were bis(pyrrolyl) complexes without the methylene connector. Reactions of 2-arylpyrroles where the aryl group was 3,5-(CF3)2C6H3, mesityl, 4-(CF3)C6H4, and p-tolyl generated Ti(NMe2)2(pyrr3,5-CF3)2, Ti(NMe2)2(pyrrmes)2, Ti(NMe2)2(pyrr4-CF3)2, and Ti(NMe2)2(...
Measurement and modeling of extraction of chlorinated hydrocarbons from water with supercritical carbon dioxide

Abstract Supercritical-fluid extraction (SCFE) for the removal of toxic chlorinated organics from water has been studied using a continuous-flow view-cell system. The solubilities of pure 1,2-dichloroethane, 1,1,2-trichloroethane, and 1,1,2,2,-tetrachloroethane in subcritical and supercritical C02 have been obtained at 313.2 and 323.2 K and over a pressure range of 6.2–8.27 MPa. All the compounds studied were completely miscible in C02 at the temperatures studied and at pressure > 9 MPa. Equilibrium data for the removal of these compounds from water using supercritical C02 were obtained at two temperatures (313.2 and 323.2 K) and over a pressure range 9.65-16.54 MPa. The distribution coefficients (K-values) of these three compounds between supercritical C02 and an aqueous phases were in the range of 20 to 200. These high distribution coefficients verify that extraction with supercritical C02 is an effective method to remove chlorinated hydrocarbons from water. The results have been modeled using a hardsphere, perturbation-theory-based Camahan-Starling-DeSantis-Redlich-Kwong equation of state and simple mixture rules.
An integrative approach to delimiting species in a rare but widespread mycoheterotrophic orchid

In the spirit of recent calls for species delimitation studies to become more pluralistic, incorporating multiple sources of evidence, we adopted an integrative, phylogeographic approach to delimiting species and evolutionarily significant units (ESUs) in the Corallorhiza striata species complex. This rare, North American, mycoheterotrophic orchid has been a taxonomic challenge regarding species boundaries, displaying complex patterns of variation and reduced vegetative morphology. We employed plastid DNA, nuclear DNA and morphometrics, treating the C. striata complex as a case study for integrative species delimitation. We found evidence for the differentiation of the endangered C. bentleyi (eastern USA) + C. striata var. involuta (Mexico) from the remaining C. striata (= C. striata s.s.; USA, Canada, Mexico). Corallorhiza striata involuta and C. bentleyi, disjunct by thousands of kilometres (Mexico-Appalachia), were genetically identical but morphologically distinct. Evidence suggests the C. striata complex represents three species: C. bentleyi, C. involuta and a widespread C. striata s.s under operational criteria of diagnosability and common allele pools. In contrast, Bayesian coalescent estimation delimited four species, but more informative loci and a resultant species tree will be needed to place higher confidence in future analyses. Three distinct groupings were identified within C. striata s.s., corresponding to C. striata striata, C. striata vreelandii, and Californian accessions, but these were not delimited as species because of occupying a common allele pool. Each comprises an ESU, warranting conservation considerations. This study represents perhaps the most geographically comprehensive example of integrative species delimitation for any orchid and any mycoheterotroph.
Computer supported cooperative work

As the information highway becomes a reality and appropriate hardware and software become readily available, anyone using a computer will be able to engage in some form of computer-supported cooperative work within the next few years. However, much work remains to be done to bring computer supported cooperative work (CSCW) into everyday use, including: developing user-friendly software; addressing the social dynamics of group activities; standardizing various terms; and handling the difficult interactions between multiple tasks performed by multiple groups. The paper considers some of the difficult problems relating to the technological developments that will enable people to work in any mode. >
Outcome of sex reassignment surgery for transsexuals

Fifteen years ago the author reviewed the world literature on male transsexualism (Pauly, 1965). Subsequently he summarized the results of sex reassignment surgery for male and female transsexuals ...
Effect of Zr/Ti Ratio on The Fatigue and Retention Behavior of Sol-Gel Derived Pzt Films

A series of sol-gel derived PZT films with various Zr/Ti ratios - namely FT, 0/100 - 20/80, 35/65, 53/47, 65/35, 80/20, 94/6 and PZ, 100/0 - were prepared on platinized Si wafers. Excess PbO was added to the precursor chemistries to compensate for eventual PbO loss and also to aid in obtaining the desired perovskite phase. It was found that the phase assembly, namely the presence of tetragonal or rhombohedral perovskite phases, plays an important role in determining the fatigue and retention behavior. PT-rich (or tetragonal) films offer better retention characteristics than those observed in PZ-rich (or rhombohedral) or PZT 53/47 films. Films with PZ-rich compositions tend to exhibit superior fatigue behavior compared with PT-rich films.
Sebaceous neoplasm with reticulated and cribriform features: a rare variant of sebaceoma

Troy and Ackerman defined the term sebaceoma (Am J Dermatopathol 1984: 6: 7-13) as benign neoplasm of basaloid cells with varying numbers of mature sebocytes. Steffen and Ackerman (Neoplasms with sebaceous differentiation. Philadelphia: Lee and Febiger, 1994: 401-425) illustrated many examples of sebaceoma, two of which had a reticulated and cribriform pattern. We report a case of sebaceoma from the scalp of a 52-year-old white female. Histologically, it displayed reticulated and cribriform basaloid epithelial islands. This is the third reported case of sebaceoma, to our knowledge, with these unusual features.
A computer simulation of oscillatory behavior in primary visual cortex

Periodic variations in correlated cellular activity have been observed in many regions of the cerebral cortex. The recent discovery of stimulus-dependent, spatially-coherent oscillations in primary visual cortex of the cat has led to suggestions of neural information encoding schemes based on phase and/or frequency variation. To explore the mechanisms underlying this behavior and their possible functional consequences, we have developed a realistic neural model, based on structural features of visual cortex, which replicates observed oscillatory phenomena. In the model, this oscillatory behavior emerges directly from the structure of the cortical network and the properties of its intrinsic neurons; however, phase coherence is shown to be an average phenomenon seen only when measurements are made over multiple trials. Because average coherence does not ensure synchrony of firing over the course of single stimuli, oscillatory phase may not be a robust strategy for directly encoding stimulus-specific information. Instead, the phase and frequency of cortical oscillations may reflect the coordination of general computational processes within and between cortical areas. Under this interpretation, coherence emerges as a result of horizontal interactions that could be involved in the formation of receptive field properties.
Bifurcus semigroups and rings

Donald Adams San Diego State University (graduate student) Rene Ardila City College of New York (undergraduate) David Hannasch University of Nevada at Las Vegas (undergraduate) Audra Kosh University of California at Santa Barbara (undergraduate) Hanah McCarthy Lawrence University (undergraduate) Vadim Ponomarenko Department of Mathematics and Statistics, San Diego State University, 5500 Campanile Drive, San Diego CA 92182-7720 E-mail: vadim@sciences.sdsu.edu Ryan Rosenbaum San Diego State University (undergraduate)
Multidimensional wave-packet analysis : splitting method for time-resolved property determination

The splitting method is an approach for preventing unphysical behavior of a wave-packet at the edges of its coordinate space representation grid. We examine here the possibilities and limits of using this method to perform time-resolved analysis of the products of molecular processes.