Clear Explanation (clear + explanation)

Distribution by Scientific Domains


Selected Abstracts


Assessing the sources and magnitude of diurnal nitrate variability in the San Joaquin River (California) with an in situ optical nitrate sensor and dual nitrate isotopes

FRESHWATER BIOLOGY, Issue 2 2009
BRIAN A. PELLERIN
Summary 1.,We investigated diurnal nitrate (NO3,) concentration variability in the San Joaquin River using an in situ optical NO3, sensor and discrete sampling during a 5-day summer period characterized by high algal productivity. Dual NO3, isotopes (,15NNO3 and ,18ONO3) and dissolved oxygen isotopes (,18ODO) were measured over 2 days to assess NO3, sources and biogeochemical controls over diurnal time-scales. 2.,Concerted temporal patterns of dissolved oxygen (DO) concentrations and ,18ODO were consistent with photosynthesis, respiration and atmospheric O2 exchange, providing evidence of diurnal biological processes independent of river discharge. 3.,Surface water NO3, concentrations varied by up to 22% over a single diurnal cycle and up to 31% over the 5-day study, but did not reveal concerted diurnal patterns at a frequency comparable to DO concentrations. The decoupling of ,15NNO3 and ,18ONO3 isotopes suggests that algal assimilation and denitrification are not major processes controlling diurnal NO3, variability in the San Joaquin River during the study. The lack of a clear explanation for NO3, variability likely reflects a combination of riverine biological processes and time-varying physical transport of NO3, from upstream agricultural drains to the mainstem San Joaquin River. 4.,The application of an in situ optical NO3, sensor along with discrete samples provides a view into the fine temporal structure of hydrochemical data and may allow for greater accuracy in pollution assessment. [source]


Theoretical study on the second-order nonlinear optical properties of nonconjugated D-,-A chromophores

INTERNATIONAL JOURNAL OF QUANTUM CHEMISTRY, Issue 7 2009
Guochun Yang
Abstract Density functional theory calculations have been carried out on nonconjugated D-,-A chromophores to investigate the different electron donors and conjugated bridges effects on the molecular nonlinear optical response. The results show that the large second-order polarizability values can be achieved through careful combination of available electron donors, conjugated bridges for our studied nonconjugated D-,-A chromophores. The calculations also provide a clear explanation for the second-order polarizability changes from the standpoint of transition energies, oscillator strengths, electron density difference, and bond length alternation. Solvent effect has great influence on the second-order polarizability and electronic absorption spectrum. It is hoped that the results presented in this article will give some hints to the interrelated studies. © 2009 Wiley Periodicals, Inc. Int J Quantum Chem, 2009 [source]


The Validity of a Personality Disorder Diagnosis for People with an Intellectual Disability

JOURNAL OF APPLIED RESEARCH IN INTELLECTUAL DISABILITIES, Issue 3 2008
Jessica Moreland
Background, It has long been appreciated that people with intellectual disabilities experience mental health problems. Studies into the prevalence of personality disorder in the population of people with an intellectual disability indicate significant variations, which have no clear explanation. Method, Work on personality disorder and personality is reviewed. Results, This article will outline some of the reasons for the variations in the reported prevalence figures including the impact of diagnostic overshadowing, problems inherent within the diagnostic classification systems and instruments that have a significant impact upon the reliability of a diagnosis. It will also argue that there are some fundamental issues relating to the validity of the construct of personality disorder and its application to the population of people with intellectual disabilities. The article notes that the model of personality, which in itself is not without critics, is derived from research on the general population and has not been integrated with personality research conducted within the population of people with an intellectual disability. Conclusion, It is suggested that the current diagnostic systems need to be reviewed in the context of an existing evidence base from within the field of intellectual disabilities. There are grounds to be cautious with the current diagnostic process and to question its clinical utility. Furthermore, diagnosis may only serve as an intermediate step and as part of a more detailed nomothetic approach. [source]


EMDR: A putative neurobiological mechanism of action

JOURNAL OF CLINICAL PSYCHOLOGY, Issue 1 2002
Robert Stickgold
Numerous studies have provided evidence for the efficacy of eye movement desensitization and reprocessing therapy (EMDR) in the treatment of posttraumatic stress disorder (PTSD), including recent studies showing it to be more efficient than therapist-directed flooding. But few theoretical explanations of how EMDR might work have been offered. Shapiro, in her original description of EMDR, proposed that its directed eye movements mimic the saccades of rapid eye movement sleep (REM), but provided no clear explanation of how such mimicry might lead to clinical improvement. We now revisit her original proposal and present a complete model for how EMDR could lead to specific improvement in PTSD and related conditions. We propose that the repetitive redirecting of attention in EMDR induces a neurobiological state, similar to that of REM sleep, which is optimally configured to support the cortical integration of traumatic memories into general semantic networks. We suggest that this integration can then lead to a reduction in the strength of hippocampally mediated episodic memories of the traumatic event as well as the memories' associated, amygdala-dependent, negative affect. Experimental data in support of this model are reviewed and possible tests of the model are suggested. © 2002 John Wiley & Sons, Inc. J Clin Psychol 58: 61,75, 2002. [source]


Japanese cancer patients' communication style preferences when receiving bad news

PSYCHO-ONCOLOGY, Issue 7 2007
Maiko Fujimori
Abstract This study describes the communication style preferences of Japanese patients when receiving bad news, examines the factor structure of the measure for patients' preferences (MPP) in a Japanese population, and explores variables that may be associated with patients' communication style preferences. Five hundred twenty-nine cancer outpatients completed several psychosocial measures including the Japanese version of the MPP (MPP-J), the Mental Adjustment to Cancer Scale (MAC), and the Hospital Anxiety and Depression Scale (HADS). The patients desired detailed information and a supportive environment when receiving bad news. The MPP-J demonstrated a 5-factor structure: support, facilitation, medical information, clear explanation, and encouraging question-asking. Regression analyses indicated that a female gender, the fighting spirit and anxious preoccupation dimensions of the MAC were positively associated with all 5 MPP-J factors. In conclusion, Japanese cancer patients' preferences for communication when receiving bad news differ somewhat from those of American patients. Japanese physicians should encourage patients to ask questions and should consider the demographic (e.g. gender), medical (disease status) and psychosocial characteristics (fighting spirit and anxious preoccupation) of patients when delivering bad news. Copyright © 2006 John Wiley & Sons, Ltd. [source]


Effect of Managed Care Enrollment on Primary and Repeat Cesarean Rates Among U.S. Department of Defense Health Care Beneficiaries in Military and Civilian Hospitals Worldwide, 1999,2002

BIRTH, Issue 4 2004
Andrea Linton MS
However, little conclusive evidence exists to support this solution. We undertook a study of the Department of Defense health care beneficiary population to assess the impact of enrollment in TRICARE Prime, the Department's managed care health plan, on cesarean delivery rates. Methods: Pooled hospital discharge records from 1999,2002 for live, singleton births were analyzed to calculate primary and repeat cesarean rates for TRICARE Prime and non-Prime beneficiaries in the military and civilian hospitals that comprise the Department of Defense health care network. Stepwise logistic regression was used to calculate adjusted odds ratios for clinical indicators for each combination of health plan and hospital setting using the,2difference(p < 0.05)to eliminate nonsignificant variables from the model. Total primary and repeat cesarean rates were compared with primary and repeat cesarean rates for women with no reported clinical complications to account for differences in case mix across subgroups. Statistical significance of the differences calculated for subgroups was assessed using,2. Results: Primary cesarean rates were significantly lower for TRICARE Prime enrollees relative to non-Prime beneficiaries for all race subgroups and three of five age subgroups in military hospitals and four of five age subgroups in civilian hospitals. No significant differences in repeat cesarean rates were observed between Prime and non-Prime beneficiaries within any race or age subgroup. Breech presentation followed by dystocia, fetal distress, and other complications were significant predictors for primary cesarean. Previous cesarean delivery was the leading predictor for repeat cesarean delivery. Primary and repeat cesarean rates observed for military hospitals were consistently lower than rates observed for civilian hospitals within each health plan type and age group. Conclusions: Enrollment in the managed care health plan was significantly associated with lower risk of primary cesarean delivery relative to membership in other health plans offered to Department of Defense health care beneficiaries. Repeat cesarean rates in this population varied independently of health plan type. Primary cesarean delivery was generally associated with clinical complications, whereas previous cesarean delivery was the strongest indictor for a repeat cesarean delivery. A clear explanation of reduced cesarean rates for Prime enrollees remains elusive, but it is likely that factors beyond individual practitioner decision-making were at work. [source]


Patient priorities of care in rheumatology outpatient clinics: a qualitative study

MUSCULOSKELETAL CARE, Issue 4 2007
Vicky Ward PhD
Abstract Objective:,To provide more understanding of what rheumatoid arthritis (RA) patients want and need from an outpatient visit. Methods:,25 patients who experienced care in a nurse practitioner clinic (n = 10), junior doctor clinic (n = 9) or consultant clinic (n = 6) in a large teaching hospital in West Yorkshire were interviewed about their perceptions and experiences of care. Interviews were approximately 11/2 hours in duration and were carried out in a neutral environment by a research nurse. Interview data were subjected to atheoretical content analysis, which resulted in the identification of emergent themes. Results:,Five main themes emerged from the analysis of interview data: 1) patients want to be communicated to clearly and effectively and value positive relationships with practitioners. These help to give patients confidence in the care they are receiving; 2) patients want to feel in control of their condition and tend to refuse interventions as a way of gaining control; 3) patients want to be given clear explanations during consultations, and want information in oral and written forms; 4) patients want to be able to access practitioners between scheduled appointments as a way of gaining reassurance; and 5) patients want to feel valued by society through having their difficulties appreciated and understood by others. Conclusion:,This research adds to the body of evidence on what patients want from their rheumatology care, and each theme has clear implications for future practice. Copyright © 2007 John Wiley & Sons, Ltd. [source]


In this issue: Biotechnology Journal 9/2010

BIOTECHNOLOGY JOURNAL, Issue 9 2010
Article first published online: 10 SEP 2010
Linking obesity and colorectal cancer Sung and Bae, Biotechnol. J. 2010, 5, 930,941 Obesity is known as one of the most closely related risk factors of colorectal cancer (CRC). However, due to the complicated nature of the diet, it has been very difficult to provide clear explanations and molecular mechanisms for the role of dietary components in carcinogenesis. Nutrigenomics has become a powerful tool to study the relationships between food components and genes. It includes nutrigenetics (dealing with genetic variations related to phenotypic changes in response to diet), nutritional epigenomics and nutritional transcriptomics/proteomics/metabolomics. This review summarizes data on genes, proteins and metabolites that are related to either obesity or CRC and candidate molecules that may link obesity and CRC. The application of bioinformatics helps to perform large-scale network analysis to study cause-effect relationships between dietary components and CRC in the future. Hepatoprotective effects of oleuropein Kim et al., Biotechnol. J. 2010, 5, 950,960 Oleuropein, an active constituent of olive leaf, has a variety of pharmacological activities associated with its capacity to scavenge reactive oxygen species and has a protective effect against non-alcoholic fatty liver disease (NAFLD) in vivo. To gain insights into the molecular mechanisms of its hepatoprotective action the group of Taesun Park (Seoul, Korea) fed mice with a high fat diet supplemented with oleuropein. Then, liver tissue was subjected to DNA microarray analysis. Oleuropein in high fat diet reduced the mRNA level of regulators of hepatic fatty acid uptake and transport. The expression of a number of genes involved in oxidative stress responses, detoxification of lipid peroxidation products and proinflammatory cytokine genes were reduced, while highly regulated transcription factors were implicated in the lipogenesis, inflammation, insulin resistance and fibrosis, underlying the multifactorial effect of oleuropein on NAFLD. Genetic variations in obesity and diabetes Varma et al., Biotechnol. J. 2010, 5, 942,949 Obesity is a state of metabolic deregulation and a leading cause for development of type 2 diabetes, which are complex polygenic diseases. Here, authors from the National Centre of Toxicological Research at the FDA (Jefferson, Arizona, USA) used a data mining approach to evaluate the role of carbohydrate metabolic pathway genes in the development of obesity and type 2 diabetes. Data from public databases were used to map the position of these genes to known quantitative trait loci (QTL) and to find sequence and structural genetic variants such as single nucleotide polymorphisms (SNPs). The results demonstrated that a majority of carbohydrate metabolic pathways genes are associated with QTL for obesity and many for type 2 diabetes. This data mining approach can establish a strategy for interpreting an individual's risk factor for disease development, instead of population attributable risks. [source]


Linking obesity to colorectal cancer: Application of nutrigenomics

BIOTECHNOLOGY JOURNAL, Issue 9 2010
Professor Mi-Kyung Sung
Abstract Diet is one of the most affective environmental factors in cancer development. Due to complicated nature of the diet, it has been very difficult to provide clear explanations for the role of dietary components in carcinogenesis. However, as high-throughput omics techniques became available, researchers are now able to analyze large sets of gene transcripts, proteins, and metabolites to identify molecules involved in disease development. Bioinformatics uses these data to perform network analyses and suggest possible interactions between metabolic processes and environmental factors. Obesity is known as one of the most closely related risk factors of colorectal cancer (CRC). Metabolic disturbances due to a positive energy balance may trigger and accelerate CRC development. In this review, we have summarized reports on genes, proteins and metabolites that are related to either obesity or CRC, and suggested candidate molecules linking obesity and CRC based on currently available literature. Possible application of bioinformatics for a large scale network analysis in studying cause-effect relationship between dietary components and CRC are suggested. [source]


The asthma,obesity link in childhood: open questions, complex evidence, a few answers only

CLINICAL & EXPERIMENTAL ALLERGY, Issue 4 2007
P. M. Matricardi
Summary Obesity and asthma are public health priorities in developed countries. Genes which may contribute to the control of both conditions include those encoding for the ,2 -adrenergic receptor, tumour necrosis factor-, (TNF-,) and the insulin-like growth factor 1 (IGF-1). Prospective studies consistently supported a link between obesity and reported wheezing or asthma diagnosis in children. However, there are still no clear explanations for such a link. On one hand, overweight asthmatic children may perceive their asthma as worse. On the other hand, atopic sensitization and bronchial hyper-reactivity do not explain the observed associations. After puberty, the association between asthma and obesity tends to be stronger in girls than in boys. It is conceivable that severe obesity in adolescent females may aggravate asthma through mechanisms different from those linking prepubertal obesity to unremitting asthma in males. Future studies should therefore address multiple age- and gender-specific hypotheses about the mechanisms that link obesity to asthma throughout childhood. [source]