Additional Research (additional + research)

Distribution by Scientific Domains
Distribution within Medical Sciences


Selected Abstracts


Photodynamic Therapy for the Treatment of Cutaneous Neoplasia, Inflammatory Disorders, and Photoaging

DERMATOLOGIC SURGERY, Issue 5 2009
EMILY TIERNEY MD
BACKGROUND Photodynamic therapy (PDT) has demonstrated high efficacy, minimal side effects, and improved cosmetic outcome when used for the treatment of actinic keratoses (AK), basal cell carcinoma (BCC), squamous cell carcinoma, and photoaging. METHODS To review the literature on the use of PDT in dermatologic surgery using MEDLINE. RESULTS Published clinical studies using PDT in the treatment of AKs yield overall efficacy rates ranging from 50% to 71% with one treatment to as high as 88% to 90% with two or more treatments. For superficial BCC, initial clearance rates were 76% to 97%, and for Bowen's disease, initial clearance rates ranged from 72% to 94% overall. The use of PDT for photorejuvenation is a relatively new application of this technology, which has shown promise in improving the appearance of fine lines, pigmentary variation, and telangiectasias. CONCLUSIONS The advantages of photodynamic therapy include the capacity for noninvasive targeted therapy through topical application of aminolevulinic acid and methyl aminolevulinic acid, with outstanding cosmetic results. Although the theory behind the use of chemical photosensitizers and ultraviolet light to treat a wide variety of skin disorders is straightforward, the practical application of this technology is evolving. Additional research into the precise mechanisms of action for specific photosensitizers and optimal light sources will be highly beneficial to the advancement of this technology. [source]


Development of swallowing and feeding: Prenatal through first year of life

DEVELOPMENTAL DISABILITIES RESEARCH REVIEW, Issue 2 2008
Amy L. Delaney
Abstract The development of feeding and swallowing involves a highly complex set of interactions that begin in embryologic and fetal periods and continue through infancy and early childhood. This article will focus on swallowing and feeding development in infants who are developing normally with a review of some aspects of prenatal development that provide a basis for in utero sucking and swallowing. Non-nutritive sucking in healthy preterm infants, nipple feeding in preterm and term infants, and selected processes of continued development of oral skills for feeding throughout the first year of life will be discussed. Advances in research have provided new information in our understanding of the neurophysiology related to swallowing, premature infants' sucking and swallowing patterns, and changes in patterns from preterm to near term to term infants. Oral skill development as texture changes are made throughout the second half of the first year of life is an under studied phenomenon. Knowledge of normal developmental progression is essential for professionals to appreciate differences from normal in infants and children with feeding and swallowing disorders. Additional research of infants and children who demonstrate overall typical development in oral skills for feeding is encouraged and will provide helpful reference points in increasing understanding of children who exhibit differences from typical development. It is hoped that new technology will provide noninvasive means of delineating all phases of sucking and swallowing from prenatal through infancy. Further related topics in other articles of this issue provide a comprehensive review of factors influencing oral intake, growth, nutrition, and neurodevelopmental status of children. © 2008 Wiley-Liss, Inc. Dev Disabil Res Rev 2008;14:105,117. [source]


Biofeedback for foot offloading in diabetic patients with peripheral neuropathy

DIABETIC MEDICINE, Issue 1 2010
Z. Pataky
Diabet. Med. 27, 61,64 (2010) Abstract Aims, The reduction of high plantar pressure in diabetic patients with peripheral neuropathy is mandatory for prevention of foot ulcers and amputations. We used a new biofeedback-based method to reduce the plantar pressure at an at-risk area of foot in diabetic patients with peripheral neuropathy. Methods, Thirteen diabetic patients (age 60.8 ± 12.3 years, body mass index 29.0 ± 5.0 kg/m2) with peripheral neuropathy of the lower limbs were studied. Patients with memory impairment were excluded. The portable in-shoe foot pressure measurement system (PEDAR®) was used for foot offloading training by biofeedback. The learning procedure consisted in sequences of walking (10 steps), each followed by a subjective estimation of performance and objective feedback. The goal was to achieve three consecutive walking cycles of 10 steps, with a minimum of seven steps inside the range of 40,80% of the baseline peak plantar pressure. The peak plantar pressure was assessed during the learning period and at retention tests. Results, A significant difference in peak plantar pressure was recorded between the beginning and the end of the learning period (when the target for plantar pressure was achieved) (262 ± 70 vs. 191 ± 53 kPa; P = 0.002). The statistically significant difference between the beginning of learning and all retention tests persisted, even at the 10-day follow-up. Conclusions, Terminal augmented feedback training may positively affect motor learning in diabetic patients with peripheral neuropathy and could possibly lead to suitable foot offloading. Additional research is needed to confirm the maintenance of offloading in the long term. [source]


The promise and the potential consequences of the global transport of mycorrhizal fungal inoculum

ECOLOGY LETTERS, Issue 5 2006
Mark W. Schwartz
Abstract Advances in ecology during the past decade have led to a much more detailed understanding of the potential negative consequences of species' introductions. Moreover, recent studies of mycorrhizal symbionts have led to an increased knowledge of the potential utility of fungal inoculations in agricultural, horticultural and ecological management. The intentional movement of mycorrhizal fungal species is growing, but the concomitant potential for negative ecological consequences of invasions by mycorrhizal fungi is poorly understood. We assess the degree to which introductions of mycorrhizal fungi may lead to unintended negative, and potentially costly, consequences. Our purpose is to make recommendations regarding appropriate management guidelines and highlight top priority research needs. Given the difficulty in discerning invasive species problems associated with mycorrhizal inoculations, we recommend the following. First, careful assessment documenting the need for inoculation, and the likelihood of success, should be conducted prior to inoculation because inoculations are not universally beneficial. Second, invasive species problems are costly and often impossible to control by the time they are recognized. We recommend using local inoculum sources whenever possible. Third, non-sterile cultures of inoculum can result in the movement of saprobes and pathogens as well as mutualists. We recommend using material that has been produced through sterile culture when local inoculum is not available. Finally, life-history characteristics of inoculated fungi may provide general guidelines relative to the likelihood of establishment and spread. We recommend that, when using non-local fungi, managers choose fungal taxa that carry life-history traits that may minimize the likelihood of deleterious invasive species problems. Additional research is needed on the potential of mycorrhizal fungi to spread to non-target areas and cause ecological damage. [source]


Differential impact of state tobacco control policies among race and ethnic groups

ADDICTION, Issue 2007
John A. Tauras
ABSTRACT Aims This paper describes patterns of racial and ethnic cigarette use in the United States and discusses changes in state-level tobacco control policies. Moreover, this paper reviews the existing econometric literature on racial and ethnic smoking and discusses the limitations of that research. Finally, this paper outlines an agenda for future research. Methods Patterns of racial and ethnic smoking and changes in state-level tobacco control policies in the United States were obtained from a variety of sources, including surveys and government and private documents and databases. After an extensive literature search was completed, the existing research was scrutinized and recommendations for much-needed future research were put forth. Findings Despite the fact that certain racial and ethnic minorities bear a disproportionate share of the overall health burden of tobacco, less than a handful of econometric studies have examined the effects of state-level public policies on racial and ethnic smoking. The existing literature finds Hispanics and African Americans to be more responsive to changes in cigarette prices than whites. Only one study examined other state-level tobacco policies. The findings from that study implied that adolescent white male smoking was responsive to changes in smoke-free air laws, while adolescent black smoking was responsive to changes in youth access laws. Conclusions While much has been learned from prior econometric studies on racial and ethnic smoking in the United States, the existing literature suffers from numerous limitations that should be addressed in future research. Additional research that focuses on races and ethnicities other than white, black and Hispanic is warranted. Furthermore, future studies should use more recent data, hold sentiment toward tobacco constant and control for a comprehensive set of tobacco policies that take into account not only the presence of the laws, but also the level of restrictiveness of each policy. [source]


Individual Odour Similarity and Discrimination in the Coruro (Spalacopus cyanus, Octodontidae)

ETHOLOGY, Issue 6 2006
Petra Hagemeyer
Previous studies of subterranean, fossorial and above-ground rodents have demonstrated that similarities in individual odours covary with genetic similarities thus supporting the theory of odour-genes covariance (i.e. the closer the individuals are genetically, the greater the similarities between their odours). We used the habituation-generalization paradigm, where the subject is exposed to the same odour stimulus in three consecutive habituation trials followed by two test trials in which the odour from two other individuals are presented successively. Using this test design, we showed that the socially living coruros (Spalacopus cyanus) discriminate individuals on the basis of their ano-genital odours and also respond to odour similarities between individuals. Male and female subjects treated ano-genital odours of two same-sex family members and also the odours of two sibling strangers as different to each other. At the same time, they treated the odours of siblings as similar compared with the odour of an unrelated individual. No gender differences were detected. Our results contrast with those from other rodent species that did not spontaneously discriminate between individual odours of siblings from a different family than their own. The polygyneous lifestyle may provide the selective background for that difference. Additional research will be necessary to explore this hypothesis and to rule out differences due to dietary preferences and due to the type of paradigm chosen for the tests. [source]


Strain-life approach in thermo-mechanical fatigue evaluation of complex structures

FATIGUE & FRACTURE OF ENGINEERING MATERIALS AND STRUCTURES, Issue 9 2007

ABSTRACT This paper is a contribution to strain-life approach evaluation of thermo-mechanically loaded structures. It takes into consideration the uncoupling of stress and damage evaluation and has the option of importing non-linear or linear stress results from finite element analysis (FEA). The multiaxiality is considered with the signed von Mises method. In the developed Damage Calculation Program (DCP) local temperature-stress-strain behaviour is modelled with an operator of the Prandtl type and damage is estimated by use of the strain-life approach and Skelton's energy criterion. Material data were obtained from standard isothermal strain-controlled low cycle fatigue (LCF) tests, with linear parameter interpolation or piecewise cubic Hermite interpolation being used to estimate values at unmeasured temperature points. The model is shown with examples of constant temperature loading and random force-temperature history. Additional research was done regarding the temperature dependency of the Kp used in the Neuber approximate formula for stress-strain estimation from linear FEA results. The proposed model enables computationally fast thermo-mechanical fatigue (TMF) damage estimations for random load and temperature histories. [source]


Mechanisms and modes for ignition of low-voltage, PVC-insulated electrotechnical products

FIRE AND MATERIALS, Issue 2 2006
Vytenis BabrauskasArticle first published online: 1 AUG 200
Abstract PVC is the most common insulation material used for wiring in low-voltage (LV) service. ,Low-voltage', in the context of this paper, is taken to be 120,240 VAC. The electrotechnical products considered include insulated wires, cables and cords, and also appurtenant termination devices, e.g. male plugs or female taps. Well-known factors leading to the ignition of PVC-insulated wiring and related products include: (a) manufacturing defects; (b) grossly excessive current; (c) over-insulation, sometimes augmented by overcurrent; (d) localized heating due to strand breakage; (e) localized heating due to mechanical strand severing by staples or nails; and (f) localized heating due to failed terminations. Other failure modes are known but have received only limited study. These include (i) excessive force and creep; (ii) chemical interaction effects; and (iii) breakdown under voltage surge conditions. Additional research is needed in these areas. The proximate cause of ignition involved with many of the above mechanisms is arc tracking (arcing across a carbonized path). In turn, it is shown that PVC is especially susceptible to becoming charred, it requiring only approximately 160°C for the material to become semiconducting during short-term exposure (around 10 h), while longer-term exposure (around 1 month) may cause failures at temperatures as low as 110°C. Some limited data exist which suggest that standard UL and IEC temperature classifications are unduly optimistic, as applied to PVC. Fire can originate if wiring or equipment cannot withstand a powerline surge. Mains-connected electrical appliances need to be designed to resist 6000 V surge voltages, even though this is not mandated in most of the current UL and IEC standards. Data are presented showing that the IEC 60112 wet-tracking test gives especially misleading results for PVC and should be improved or abrogated. Copyright © 2005 John Wiley & Sons, Ltd. [source]


A review of the effects of catch-and-release angling on black bass, Micropterus spp.: implications for conservation and management of populations

FISHERIES MANAGEMENT & ECOLOGY, Issue 2 2007
M. J. SIEPKER
Abstract, This paper summarises recent peer-reviewed literature addressing the effects of catch-and-release angling on black bass, Micropterus spp., to facilitate management and conservation of these fish. Traditionally, the effects of catch and release have been evaluated by measuring mortality. Many recent studies have measured sublethal effects on physiology and behaviour. There is also greater emphasis on adding more realism to sublethal catch-and-release experiments through angler involvement in research activities and by conducting studies in the field rather than in laboratory environments. Owing to these advances, there have been a number of recent findings, which are summarised here, related to air exposure, gear (e.g. circle hooks) and the weigh-in procedure that are particularly relevant to black bass anglers, tournament organisers and fishery managers. Additional research is particularly needed for: (1) population-level effects of angling for nesting fish; (2) population-level effects of tournament-associated mortality; (3) effectiveness of livewell additives for enhancing survival; (4) consequences of fish displacement in competitive events; (5) effects of weigh-in procedures and other organisational issues on fish condition and survival; and (6) reducing barotrauma. [source]


A comparison of bacteria and benthic invertebrates as indicators of ecological health in streams

FRESHWATER BIOLOGY, Issue 7 2009
G. LEAR
Summary 1. We set out to evaluate the reliability of bacterial communities as an indicator of freshwater ecological health. 2. Samples of epilithic biofilm were taken over a 1-year period from four streams, each impacted by varying degrees of human modification. The bacteria within each sample were characterised using a whole community DNA fingerprinting technique (automated ribosomal intergenic spacer analysis). Spatial and temporal differences in community structure between samples were visualised using multi-dimensional scaling and quantified using permutational multivariate anova. Macrobenthic invertebrates, which are commonly used as indicators of stream ecological health, were also sampled for comparison. 3. Multivariate analysis revealed a clear gradient in macroinvertebrate community structure between sites exposed to increased human impact. Bacterial communities, however, could only distinguish the most impacted site from the remainder. 4. Additional research is required to increase the sensitivity of bacterial community analyses before endorsing their use as an indicator of freshwater ecological health. [source]


Cost,benefit analysis involving addictive goods: contingent valuation to estimate willingness-to-pay for smoking cessation

HEALTH ECONOMICS, Issue 2 2009
David L. Weimer
Abstract The valuation of changes in consumption of addictive goods resulting from policy interventions presents a challenge for cost,benefit analysts. Consumer surplus losses from reduced consumption of addictive goods that are measured relative to market demand schedules overestimate the social cost of cessation interventions. This article seeks to show that consumer surplus losses measured using a non-addicted demand schedule provide a better assessment of social cost. Specifically, (1) it develops an addiction model that permits an estimate of the smoker's compensating variation for the elimination of addiction; (2) it employs a contingent valuation survey of current smokers to estimate their willingness-to-pay (WTP) for a treatment that would eliminate addiction; (3) it uses the estimate of WTP from the survey to calculate the fraction of consumer surplus that should be viewed as consumer value; and (4) it provides an estimate of this fraction. The exercise suggests that, as a tentative first and rough rule-of-thumb, only about 75% of the loss of the conventionally measured consumer surplus should be counted as social cost for policies that reduce the consumption of cigarettes. Additional research to estimate this important rule-of-thumb is desirable to address the various caveats relevant to this study. Copyright © 2008 John Wiley & Sons, Ltd. [source]


Effects of Family Structure on Children's Use of Ambulatory Visits and Prescription Medications

HEALTH SERVICES RESEARCH, Issue 5 2006
Alex Y. Chen
Objective. To examine the effects of family structure, including number of parents, number of other children, and number and type of other adults, on office visits, emergency room visits, and use of prescription medications by children. Data Source. The Household Component of the 1996,2001 Medical Expenditure Panel Survey (MEPS). Study Design. The study consisted of a nationally representative sample of children 0,17 years of age living in single-mother or two-parent families. We used negative binomial regression to model office visits and emergency room visits and logistic regression to model the likelihood of prescription medication use. Our analyses adjusted for demographic and socioeconomic characteristics as well as measures of children's health and parental education and child-rearing experience. Data Collection/Extraction Method. We combined 1996,2001 MEPS Full Year Consolidated Files and Medical Conditions Files. Principal Findings. Descriptive data showed that children in single-mother families had fewer office visits than children in two-parent families; however, the effect of number of parents in the family on children's office visits or use of prescription medications was completely explained by other explanatory variables. By contrast, children living in families with many other children had fewer total and physician office visits and a lower likelihood of using a prescription medication than children living in families with no other children even after adjusting for other explanatory variables. Children who lived with other adults in addition to their parents also had fewer office visits and a lower likelihood of using a prescription medication than children who lived only with their parents. Conclusions. Children living in families with many other children or with other adults use less ambulatory care and prescription medications than their peers. Additional research is needed to determine whether these differences in utilization affect children's health. [source]


Methodologic Implications of Allocating Multiple-Race Data to Single-Race Categories

HEALTH SERVICES RESEARCH, Issue 1 2002
Article first published online: 18 MAR 200
Objective. To illustrate methods for comparing race data collected under the 1977 Federal Office of Management and Budget (OMB) directive, known as OMB-15, with race data collected under the revised 1997 OMB standard. Data Sources/Study Setting.,Secondary data from the 1993,95 National Health Interview Surveys. Multiple-race responses, available on in-house files, were analyzed. Study Design.,Race-specific estimates of employer-sponsored health insurance were calculated using proposed allocation methods from the OMB. Estimates were calculated overall and for three population subgroups: children, those in households below poverty, and Hispanics. Principal Findings.,Although race distributions varied between the different methods, estimates of employer-sponsored health insurance were similar. Health insurance estimates for the American Indian/Alaska Native group varied the most. Conclusions.,Employer-sponsored health insurance estimates for American Indian/Alaska Natives from data collected under the 1977 OMB directive will not be comparable with estimates from data collected under the 1997 standard. The selection of a method to distribute to the race categories used prior to the 1997 revision will likely have little impact on estimates of employer-sponsored health insurance for other groups. Additional research is needed to determine the effects of these methods for other health service measures. [source]


Functional Trajectories in Older Persons Admitted to a Nursing Home with Disability After an Acute Hospitalization

JOURNAL OF AMERICAN GERIATRICS SOCIETY, Issue 2 2009
Thomas M. Gill MD
OBJECTIVES: To characterize the functional trajectories of older persons admitted to a nursing home with disability after an acute hospitalization. DESIGN: Prospective cohort study of 754 community-living persons aged 70 and older who were initially nondisabled in four essential activities of daily living (ADLs). SETTING: Greater New Haven, Connecticut. PARTICIPANTS: The analytical sample included 296 participants who were newly admitted to a nursing home with disability after an acute hospitalization. MEASUREMENTS: Information on nursing home admissions, hospitalizations, and disability in essential ADLs was ascertained during monthly telephone interviews for up to 9 years. Disability was defined as the need for personal assistance in bathing, dressing, walking inside one's home, or transferring from a chair. RESULTS: The median time to the first nursing home admission with disability after an acute hospitalization was 46 months (interquartile range 27.5,75.5), and the mean number±standard deviation of ADLs that participants were disabled in upon admission was 3.0±1.2. In the month preceding hospitalization, 189 (63.9%) participants had no disability. The most common functional trajectory was discharged home with disability (46.3%), followed by continuous disability in the nursing home (27.4%), discharged home without disability (21.6%), and noncontinuous disability in the nursing home (4.4%). Only 96 (32.4%) participants returned home at (or above) their premorbid level of function. CONCLUSION: The functional trajectories of older persons admitted to a nursing home with disability after an acute hospitalization are generally poor. Additional research is needed to identify the factors responsible for these poor outcomes. [source]


The pharmacological properties of anisodamine,

JOURNAL OF APPLIED TOXICOLOGY, Issue 2 2007
Jay M. Poupko
Abstract Anisodamine is a naturally occurring atropine derivative that has been isolated, synthesized and characterized by scientists in the People's Republic of China. Like atropine and scopolamine, anisodamine is a non-specific cholinergic antagonist exhibiting the usual spectrum of pharmacological effects of this drug class. It appears to be less potent and less toxic than atropine and displays less CNS toxicity than scopolamine. Anisodamine has been shown to interact with and disrupt liposome structure which may reflect its effects on cellular membranes. Experimental evidence implicates anisodamine as an anti-oxidant that may protect against free radical-induced cellular damage. Its cardiovascular properties include depression of cardiac conduction and the ability to protect against arrhythmia induced by various agents. Anisodamine is a relatively weak ,1 adrenergic antagonist which may explain its vasodilating activity. Its anti-thrombotic activity may be a result of inhibition of thromboxane synthesis. The T1/2 of anisodamine in humans is about 2,3 h. Numerous therapeutic uses of anisodamine have been proposed including treatment of septic shock, various circulatory disorders, organophosphorus (OP) poisoning, migraine, gastric ulcers, gastrointestinal colic, acute glomerular nephritis, eclampsia, respiratory diseases, rheumatoid arthritis, obstructive jaundice, opiate addiction, snake bite and radiation damage protection. The primary therapeutic use of anisodamine has been for the treatment of septic shock. Several mechanisms have been proposed to explain its beneficial effect though most mechanisms are based upon the assumption that anisodamine ultimately acts by an improvement of blood flow in the microcirculation. Preliminary studies suggest another important therapeutic use of anisodamine is for the treatment of OP poisoning. Additional research is needed to delineate further the clinical usefulness of anisodamine relative to other anti-muscarinic drugs such as atropine and scopolamine. Copyright © 2006 John Wiley & Sons, Ltd. [source]


Association between body weight and periodontal infection

JOURNAL OF CLINICAL PERIODONTOLOGY, Issue 4 2008
Pekka Ylöstalo
Abstract Background: Besides being a risk factor for cardiovascular diseases, certain cancers and type II diabetes, obesity has been suggested to be a risk factor for periodontitis. A number of epidemiological studies have studied the association between obesity and periodontitis, but the results have been partly inconclusive. The aim of this study was to examine the association of body weight with periodontal infection. Material and Methods: The association between body weight and periodontal infection was examined using a nationally representative Health 2000 Health Examination Survey. The study was based on a subpopulation of dentate non-diabetic subjects aged 30,49 (n=2841). Periodontal infection was measured by the number of teeth with periodontal pockets of 4 mm or deeper and 6 mm or deeper. Body weight was measured using body mass index (BMI). Results: We detected a weak exposure,response association of BMI with teeth with deepened periodontal pockets after controlling for smoking habits by restricting the sample to subjects who have never smoked and for other potential confounders by including them in the multivariate models. Conclusions: The results showed an association between body weight and periodontal infection among the non-diabetic, non-smoking population aged 30,49. Additional research is needed to determine the nature of this association. [source]


Curriculum development: The venous thromboembolism quality improvement resource room

JOURNAL OF HOSPITAL MEDICINE, Issue 2 2006
Sylvia McKean MD
Abstract BACKGROUND The role of the hospitalist has evolved over the last decade, with hospitalists increasingly being asked to lead systems-based initiatives to improve the quality of inpatient care. The educational strategy of the Society of Hospital Medicine (SHM) includes development of practice-based resources to support hospitalist-led improvement in clinically important measures of hospital care quality. OBJECTIVE To develop a resource at the SHM Web site to present quality improvement (QI) principles for systems-based care in the hospital and to help individual hospitalists improve specific patient outcomes. DESIGN The SHM defined the role of the hospitalist in QI, performed an assessment of the educational needs of hospitalists, and executed a Web-based educational strategy to address these needs. The organization identified the most common cause of preventable inpatient deaths, hospital-acquired venous thromboembolism (VTE), and prioritized the need to improve prophylaxis. RESULTS This new resource at the SHM Web site presents principles for conducting QI in the hospital. To enable learning that is practice based, the VTE Quality Improvement Resource Room (QI RR) features Ask the Expert, an interactive discussion community, and an original Improvement Workbook, a downloadable project outline and tutorial that hospitalists can use to guide and document steps in an effort aimed at reducing hospital-acquired VTE. CONCLUSIONS This QI resource serves as a template for the development of subsequent hospital-based resources. User feedback will refine the QI RR and its format so that similar offerings can target other significant inpatient problems. Additional research is needed to evaluate learning and the clinical impact of this quality improvement resource on hospital performance measures and patient outcomes. Journal of Hospital Medicine 2006;1:124,132. © 2006 Society of Hospital Medicine. [source]


Capital at Home and at School: A Review and Synthesis

JOURNAL OF MARRIAGE AND FAMILY, Issue 4 2010
Toby L. Parcel
Human, financial, and social capital from several contexts affects child and adolescent well-being. Families and schools are among the most important, and research is increasingly studying how effects of capital across such contexts affect child and adolescent academic and social outcomes. Some research suggests that families may be more powerful than schools in promoting child and adolescent well-being. Additional research is needed to more fully understand how capital across institutions interacts in producing child well-being, when and why multiple institutions or levels of analysis are relevant, and how several contexts can form chains of causation. Theories of social capital may promote increased conversation among researchers who study the same outcomes yet focus their analyses on different contexts. [source]


Dendrons and dendritic catalysts immobilized on solid support: Synthesis and dendritic effects in catalysis

JOURNAL OF POLYMER SCIENCE (IN TWO SECTIONS), Issue 2 2005
Adi Dahan
Abstract Dendrimers, the aesthetically beautiful macromolecules displaying a variety of potentially useful architecture-induced properties, are traditionally assembled in solution. However, since 1988, a number of dendritic structures have been assembled on insoluble organic and inorganic polymers, and thus dendronized supports have been formed. One of the major applications of these new materials is in the field of heterogeneous catalysis. Supported dendritic catalytic systems, bearing the catalytic units on the dendron periphery, have been examined in the last 5 years in such reactions as hydroformylation, Heck and other Pd-catalyzed CC bond formations, oxidation, and enantioselective addition to aldehydes. In the majority of these studies, substantial dendritic effects on the reactivity, selectivity, or recyclability of the catalysts were observed. Although a number of factors have been suggested as sources of the effects, it is most likely that the phenomenon has a multicomponent origin. Additional research, including a full determination of the effects and their causes, is likely to lead to markedly better heterogeneous catalytic systems. © 2004 Wiley Periodicals, Inc. J Polym Sci Part A: Polym Chem 43: 235,262, 2005 [source]


Beneficial effects of omega-3 fatty acids in cardiovascular disease

JOURNAL OF SMALL ANIMAL PRACTICE, Issue 9 2010
Lisa M. Freeman
There is a large body of evidence supporting beneficial effects of omega-3 fatty acids for both primary and secondary prevention of cardiac disease in people. However, evidence is increasing for the use of omega-3 fatty acids in dogs with cardiac disease as well. Omega-3 fatty acids' anti-inflammatory and anti-arrhythmic effects may be beneficial in managing the loss of lean body mass and arrhythmias that are common in heart failure. However, omega-3 fatty acids also may have positive effects on myocardial energy metabolism, endothelial function, heart rate and blood pressure, and immune function. Additional research is needed to determine optimal indications, doses and formulations for dogs and cats with cardiac disease. [source]


Screening for Alcohol Problems in the U.S.

ALCOHOLISM, Issue 11 2002
Ethnicity, General Population: Comparison of the CAGE, RAPS, RAPS4-QF by Gender, Service Utilization
Background The purpose of this study was to compare the performance (sensitivity and specificity) of two brief screening instruments, CAGE and the Rapid Alcohol Problems Screen 4 (RAPS4), against ICD-10 and DSM-IV criteria for alcohol dependence and abuse in a representative sample of the U.S. adult household population by gender, ethnicity, and service utilization (emergency room and primary care) in the last year. Methods Data are from the Alcohol Research Group's 2000 National Alcohol Survey (n= 7612), which is a computer-assisted telephone interview survey of the U.S. general population 18 and over in all 50 U.S. states and the District of Columbia. Results Sensitivity of the RAPS4 (0.86) was better than the CAGE (0.67) given similar specificity (0.95 vs. 0.98) and outperformed the CAGE for alcohol dependence across all gender, ethnic, and service utilization groups, except among blacks and Hispanics. The RAPS4 also performed equally well for females and males (0.88 vs. 0.85), whereas sensitivity of the CAGE was lower for females. Although sensitivity of the RAPS4 was better than the CAGE for alcohol abuse, sensitivity was low for both (0.56 and 0.36, respectively). When quantity-frequency (QF) questions (drinking five or more drinks on at least one occasion during the last year and drinking as often as once a month during the last year) were added to the RAPS4, the RAPS4-QF performed significantly better for alcohol abuse and outperformed the CAGE at a cut point of one across all gender, ethnic, and service utilization groups. The RAPS4-QF appeared to be most sensitive for alcohol abuse among both males and females reporting emergency room use (0.90). Conclusions The data suggest that the RAPS4 outperforms the CAGE in this general population sample. The addition of a QF question to the RAPS4 improves performance in relation to sensitivity for alcohol abuse, and the RAPS4 and RAPS4-QF may be the instruments of choice in brief screening for alcohol use disorders. Additional research is needed to further explore these issues. [source]


Women and attention deficit disorders: A great burden overlooked

JOURNAL OF THE AMERICAN ACADEMY OF NURSE PRACTITIONERS, Issue 3 2007
Assistant Professor2), CS (Postdoctoral Research Fellow, Roberta Waite EdD
Abstract Purpose: To describe adult attention-deficit/hyperactivity disorder (ADHD) in relation to gender-based differences in symptom expression with particular emphasis on disparities concerning women, psychiatric comorbidities that affect assessment and detection, and evidenced-based treatment approaches for nurse practitioners (NPs). Data sources: Health sciences literature was reviewed using the following data-bases: Medline, Cumulative Index to Nursing and Allied Health Literature, PubMed, Proquest, Psych Info, Wiley Interscience, Cambridge Press, Science Direct, and Thomson Gale. Conclusions: Recognizing adult ADHD may be challenging; however, with increased understanding regarding the subtle variations in symptoms, use of screening instruments, and careful assessment techniques, NPs will be better able to recognize the characteristics of ADHD that are important to early detection, proper diagnosis, and effective treatment. Implications for practice: Additional research and improved clinician education may facilitate early detection and treatment of ADHD among adults of all ages and ethnic/racial backgrounds. [source]


Phosphorus status on Canadian organic farms

JOURNAL OF THE SCIENCE OF FOOD AND AGRICULTURE, Issue 15 2007
Ralph C Martin
Abstract In eastern North America, many conventional livestock farms, especially dairy farms with high inputs of feed and fertiliser have excess soil phosphorus levels and an annual phosphorus surplus. However, a Canadian dairy farm in transition to organic, without fertiliser inputs reduced its farm P surplus to a marginal level. On long-term organic dairy farms in Ontario, most soils tested low to very low in available P as measured by a standard soil test. Canadian Prairie organic grain farms also consistently demonstrate deficiencies in available soil P. Organic producers have few viable alternatives for P management. Phosphate rock can be acceptable to organic standards (provided they are low in heavy metals, and not processed synthetically), but the P in these becomes available slowly, especially in high pH soils common on most organic farms in Canada. An alternative is to increase soil P availability. Enhanced microbial activity in organically managed soils may make P more available. Livestock manures are rich sources of available phosphorus, but a majority of organic farmers in Canada do not keep livestock. Off-farm manure sources are subject to organic regulations and hauling costs, both of which may be prohibitive. Furthermore, manure from conventional farms in Canada may be contaminated by genetically modified material from corn and soybean feed. Additional research is required to improve short-term availability of soil P and long-term replacement. Copyright © 2007 Society of Chemical Industry [source]


Effect of Multiple-batch Channel Catfish, Ictalurus punctatus, Stocking Density and Feeding Rate on Water Quality, Production Characteristics, and Costs

JOURNAL OF THE WORLD AQUACULTURE SOCIETY, Issue 4 2006
Brent E. Southworth
To quantitatively define relationships among stocking densities, feeding rates, water quality, and production costs for channel catfish, Ictalurus punctatus, grown in multiple-batch systems, twelve 0.1-ha earthen ponds were stocked at 8,600, 17,300, 26,000, or 34,600 fingerlings/ha along with 2,268 kg/ha of carryover fish. Fish in all ponds were fed daily to apparent satiation using 32% protein floating feed. Temperature and dissolved oxygen in each pond were monitored twice daily; pH weekly; nitrite-N, total ammonia nitrogen, and Secchi disk visibility every 2 wk; nitrate-N, chlorophyll a, total nitrogen, total phosphorus, and chemical oxygen demand monthly; and chloride every other month. The costs of producing channel catfish at different stocking densities were estimated. There were no significant differences (P > 0.05) as a result of stocking density among treatment means of (1) gross or net yields, (2) mean weights at harvest, and (3) growth or survival of fingerlings (24,36%) and carryover fish (77,94%). Mean and maximum daily feeding rates ranged from 40 to 53 kg/ha/d and 123 to 188 kg/ha/d, respectively, and feed conversion ratios averaged 1.75. There were no differences in any feed-related parameter as a result of density. Water quality variables showed few differences among densities at samplings and no differences when averaged across the production season. Yield of fingerlings increased as stocking density increased with significant differences between the two highest and the two lowest stocking densities. Breakeven prices were lower at the higher stocking densities as a result of the higher yield of understocked fish and similar mean individual fish weights produced at these higher stocking densities. Overall, varying stocking densities of fingerlings in multiple-batch systems had little effect on production efficiency and water quality. Additional research on managing the population structure of carryover fish in commercial catfish ponds may be warranted. [source]


Effects of Gender and Size on Feed Acquisition in the Pacific White Shrimp Litopenaeus vannamei

JOURNAL OF THE WORLD AQUACULTURE SOCIETY, Issue 2 2006
Dustin R. Moss
Pacific white shrimp, Litopenaeus vannamei, are sexually dimorphic for growth, where subadult and adult females typically are larger than males of the same age. This character may be attributed to physiological and/or behavioral differences between the sexes. To determine if growth differences are the result of a more aggressive feeding behavior by females, four concurrent feeding trials were conducted to study the effects of gender and size on feed acquisition time. Feeding trials consisted of tanks (three replicate tanks per trial) stocked with (1) all females with small- and large-size groups, (2) all males with small- and large-size groups, (3) a random selection of males and females (resulting in larger females than males), and (4) males and females of equal size. Depending on the trial, tanks were stocked with either an equal number of males and females or small and large shrimp. Shrimp were fed a limited ration of squid, and the total feeding time (TFT) of shrimp between groups within a tank was compared. Results show that both gender and size are important factors in TFT as large shrimp out-competed small shrimp in both all-female and all-male feeding trials. Gender is more important than size as males out-competed females for feed even when they were smaller than competing females. These results suggest that sexual growth dimorphism is not the result of more aggressive feeding by females. In fact, males have a competitive advantage over females in acquiring feed. These results are counterintuitive because females typically are larger than males. Additional research is needed to investigate the physiological basis for sexual growth dimorphism in this commercially important shrimp. [source]


Emergency case admissions at a large animal tertiary university referral hospital during a 12-month period

JOURNAL OF VETERINARY EMERGENCY AND CRITICAL CARE, Issue 3 2008
Brett A. Dolente VMD, DACVIM
Abstract Objective: To collate and describe emergency admissions to a large animal tertiary university referral hospital during a 12-month period. Design: Prospective clinical study. Setting: Large animal tertiary university referral hospital. Animals: Large animal emergency patient admissions. Interventions: None. Measurements and main results: Information obtained from the medical record included the presenting complaint, clinical problem, admission time, duration of clinical signs before presentation, diagnostic procedures performed, therapies administered, and therapeutic procedures performed during the first 24 hours following admission, and survival to discharge. The most common category listed for the presenting complaint and clinical problem categories was gastrointestinal. Most emergency cases were admitted during the evening and in late spring, summer, and early fall. Most cases had a duration of clinical signs before presentation of >2 hours and ,8 hours (27%) or >8 hours and ,24 hours (29%). The most common diagnostic procedures performed during the first 24 hours were palpation per rectum, ultrasonographic examination, radiographs, and abdominocentesis. Antimicrobials, fluids, and nonsteroidal anti-inflammatory drugs were the most common therapies administered. Approximately 25% of cases required surgery. An exploratory celiotomy was performed in approximately 15% of cases. Enterotomy, intestinal resection and anastomosis, cesarean section, or joint or sheath lavage was each performed in <5% of cases. Overall survival to discharge was 74%. Conclusions: Large animal emergency clinicians are required to have knowledge on a wide range of diseases and should be proficient at performing numerous procedures on an emergency basis. Gastrointestinal disease is the most common type of emergency and the diagnostic and therapeutic procedures performed during the first 24 hours following admission are a reflection of this type of case. Only 25% of cases required surgery. Additional research in the form of a multicenter study and surveying both private and university practitioners needs to be performed to further define the necessary skills for an ,ideal' large animal emergency clinician. [source]


The acceptability of 360-degree judgements as a method of assessing undergraduate medical students' personal and professional behaviours

MEDICAL EDUCATION, Issue 1 2005
Charlotte Rees
Introduction, Medical students' personal and professional behaviours have been assessed poorly in medical schools. No research exists exploring the acceptability of 360-degree judgements as a method of assessing such behaviours. This study aims to explore students' and assessors' views and experiences of 360-degree judgements. Methods, Eighteen students and 12 assessors participated in 4 focus group discussions in spring 2003. Discussions were audio-taped and transcribed verbatim and the transcripts were theme analysed independently by 2 analysts. Results, Although 360-degree judgements were felt to drive students' behaviour positively, they were also thought to influence learning and behaviour adversely. Various factors were thought to influence assessors' abilities to make good quality judgements, such as situational factors like the length of time spent with students, characteristics relating to the assessment criteria and characteristics of the assessor, such as apathy. Discussion, Additional research using qualitative and quantitative methods is needed to explore these issues further. [source]


The Anticarcinogenic Potential of Soybean Lectin and Lunasin

NUTRITION REVIEWS, Issue 7 2003
Elvira Gonzalez de Mejia PhD
Cancer is one of the leading causes of death worldwide, generally exceeded only by cardiovascular disease in the developed world. The number of people diagnosed with cancer within the next few decades is expected to double. There will therefore be increased demand for novel diagnostic and medical therapies that use new non-traditional sources. Soybeans contain a variety of anticarcinogenic phytochemicals. Recently, there has been increased interest in the potential health benefits of bioactive polypeptides and proteins from soybeans, including lunasin and lectins. Lunasin is a polypeptide that arrests cell division and induces apoptosis in malignant cells. Lectins are glycoproteins that selectively bind carbohydrates; lectins are used in medicine in a variety of new applications. Additional research, including clinical trials, should continue to examine and elucidate the therapeutic effects, nutritional benefits, and toxic consequences of commonly ingested soybean lectins and lunasin. [source]


Open-Label Exploration of an Intravenous Nalbuphine and Naloxone Mixture as an Analgesic Agent Following Gynecologic Surgery

PAIN MEDICINE, Issue 6 2007
Assaf T. Gordon MD
ABSTRACT Objective., The purpose of this series was to explore a 12.5:1 fixed-dose ratio of an intravenous nalbuphine and naloxone mixture (NNM) for use in patients following gynecologic surgery. Design and Patients., Open-label, nonrandomized case series. The first series was a dose-ranging investigation for 12 patients following elective total abdominal hysterectomy or myomectomy. In this series, fentanyl was used for intraoperative analgesia, and patients were assigned to a lower NNM (2.5 mg/0.2 mg) or to a higher NNM (5 mg/0.4 mg) dose group. The second series evaluated the fixed dose of 5 mg nalbuphine/0.4 mg naloxone for four patients undergoing ambulatory gynecologic procedures. In the second series, no opioid agents were administered intraoperatively to eliminate the possibility of mu-opioid reversal by naloxone postoperatively. Outcome Measures., Pain control was assessed using a Verbal Pain Scale (0,10). Vital signs, side effects, and adverse events were recorded to determine drug safety. Results., In the first series, there were no adverse events; however, each patient required rescue medication (either morphine or fentanyl). In the second series, two of the four patients reported a reduction in pain following drug administration and did not require any further analgesic agents in the 3-hour postoperative period. One patient had an asymptomatic lowering of heart rate after receiving the drug. Conclusion., Additional research of the unique combination therapy of nalbuphine and naloxone is warranted to further determine its potential clinical efficacy and safety. [source]


Bloodstream infections in hospitalized adults with sickle cell disease: A retrospective analysis

AMERICAN JOURNAL OF HEMATOLOGY, Issue 10 2006
Lalita Chulamokha
Abstract Bloodstream infections (BSI) are a common cause of morbidity and mortality in people with sickle cell disease (SCD). In children with SCD, BSI are most often caused by encapsulated organisms. There is a surprising paucity of medical literature that is focused on evaluating SCD adults with BSI. We reviewed the charts of adults with SCD and BSI who were admitted to our hospital between April 1999 and August 2003. During this period a total of 1,692 hospital admissions for 193 adults with SCD were identified and 28% of these patients had at least 1 episode of positive blood cultures, with 69 episodes (17%) considered true BSI. Nosocomial BSI occurred in 34 episodes (49%). Among community BSI, in contrast to BSI in children with SCD, Streptococcus pneumoniae was rarely encountered. A high incidence of staphylococcal BSI in adults with SCD was noted. Twenty-eight percent of all BSI were caused by Staphylococcus aureus, and 15 of 22 isolates (68%) of these were methicillin-resistant. Gram-negative organisms, anaerobes, and yeast were found in 21 (27%), 3 (4%), and 4 isolates (5%) of BSI, respectively. Since over 80% of BSI were considered catheter-related, the higher incidence of gram-positive bacterial infections was likely due to the presence of indwelling central venous catheters. Empiric therapy for adults with SCD suspected of having BSI, especially in the presence of indwelling central venous catheters, should include antimicrobial therapy targeted at gram-positive bacteria (especially MRSA) and gram-negative bacteria. Also, if patients are critically ill, consideration should be made to include antifungal agents. Additional research into the adult SCD population appears necessary to further define this problem. Am. J. Hematol., 2006. © 2006 Wiley-Liss, Inc. [source]