bluuebunny/crossref_metadata_2025_split huggingface dataset:
Rheological and fusion behaviors of PVC micro‐ and nano‐composites evaluated from torque rheometer data
Authors: Ari Gulsen Albayrak , Aydin Ismail 
Published: January 2011

AbstractThe effects of calcium carbonate (CaCO3) particle size on the fusion and rheological behaviors of rigid poly(vinyl chloride) (PVC) composites prepared in a Haake torque rheometer were investigated by means of torque data recorded during processing. Increasing the number of particles in the same blend volume by decreasing the particle size resulted in increasing frictional forces. This increase led in turn to increased fusion torque and decreased fusion time and temperature. The power‐law‐index values of the composites increased with decreasing particle size except for 25‐nm CaCO3. The viscosities of all composites were found to decrease with shear rate; therefore, high pseudoplasticity was observed. At a particular rotor speed, viscosity of the composites decreased with decreasing particle size except for 25‐nm CaCO3. The overall results showed that the particle size of CaCO3 altered the fusion characteristics and rheological behavior of PVC. J. VINYL ADDIT. TECHNOL., 2010. © 2010 Society of Plastics Engineers
Properties of waste‐poly(ethylene terephthalate)/acrylonitrile butadiene styrene blends compatibilized with maleated acrylonitrile butadiene styrene
Authors: Lashgari Soheila , Azar A. Aref , Lashgari Somayeh , Mohammadian Gezaz Somayyeh 
Published: January 2011

AbstractWaste poly(ethylene terephthalate) (W‐PET)/acrylonitrile‐butadiene‐styrene (ABS) blends were prepared with a variety of compositions at several rotor speeds in an internal mixer, replacing ABS with different maleated ABS (ABS‐g‐MA) samples in compatibilized blends. A Box–Behnken model for three variables, with three levels, was chosen for the experimental design. ABS‐g‐MA‐based samples exhibited finer particles with a more uniform particle size distribution than ABS‐based ones, as a consequence of the compatibilizing process. Rheological results implied a greater elastic nature for compatibilized blends which increased in the presence of more ABS content; the same trend was observed for complex viscosity. With increasing ABS‐g‐MA or MA concentration, more shear thinning behavior was observed similar to that of ABS; whereas the uncompatibilized blends showed Newtonian behavior like that of W‐PET. The observed shifting in TgW‐PET and TgABS obtained from dynamic mechanical thermal analysis confirmed the good compatibility in W‐PET/ABS‐g‐MA blends in contrast with that in ordinary W‐PET/ABS blends. The mechanical properties were measured and modeled versus the various factors considered in a response surface methodology. The experimental data found a good fit with the obtained equation models. The mechanical properties of the compatibilized blends showed a large positive deviation from the mixing rule, while the uncompatibilized samples had lower properties, even compared to those predicted by the mixing rule. J. VINYL ADDIT. TECHNOL., 2010. © 2010 Society of Plastics Engineers
Survival and cause‐specific mortality of female Rocky Mountain elk exposed to human activity
Authors: Webb Stephen L. , Dzialak Matthew R. , Wondzell John J. , Harju Seth M. , Hayden‐Wing Larry D. , Winstead Jeffrey B. 
Published: January 2011

AbstractAnimal populations are becoming increasingly exposed to human activity as human populations expand and demand for energy resources (e.g., coal, oil and natural gas) increases. We initiated this study to document survival and cause‐specific mortality patterns of female Rocky Mountain elk (Cervus elaphus) exposed to increasing levels of human activity. We fitted 184 females with VHF or GPS collars over 4 years and used the Kaplan–Meier survival estimator to calculate annual survival rates. We used multinomial logistic regression to assess differences in cause‐specific mortality and generalized linear mixed models to determine how probability of survival was structured during hunting season; both analyses examined a suite of 5 covariates (i.e., age, year, extent of space use, cover, and human footprint) as potentially influencing cause‐specific mortality and survival probability. Annual probability of survival averaged 0.8 (±0.02 SE) over 4 years but averaged 0.91 (±0.03 SE) when harvest mortality was excluded, which was the most significant source of mortality in most years (). We found no difference between cause‐specific mortality sources relative to elk that survived during the hunting season (χ102 = 5.79, P = 0.832). The probability of a female surviving during hunting season was negatively influenced by age, year, extent of space use, cover, and human footprint. We found evidence that human activity may have influenced annual rates of natural survival (i.e., exclusive of hunting mortality) and probability of survival during the hunting season. We note that this study occurred largely on privately owned and managed residential and ranch land and focused on female elk; we acknowledge that survival rate and cause‐specific patterns of mortality may vary as a function of land ownership (private vs. public), demographic status, and management and harvest practices. While temporal and spatial scales of 1 week may be sufficient to describe patterns of direct mortality during hunting season, broad temporal or spatial scale analyses may be needed to address natural mortality during other seasons.
Dietaryl-arginine supplementation enhances intestinal development and expression of vascular endothelial growth factor in weanling piglets
Authors: Yao Kang , Guan Shu , Li Tiejun , Huang Ruilin , Wu Guoyao , Ruan Zheng , Yin Yulong 
Published: January 2011

Oral administration ofl-arginine has been reported to prevent gut disease in human infants. However, little is known about the effects of dietary arginine supplementation on intestinal development of weaned piglets. In the present study, twenty 21-d-old castrated piglets with 5·3 (sem0·13) kg body weight (BW) were weaned from sows, individually housed and randomly assigned to one of the two maize- and soyabean meal-based diets supplemented with 0 or 1 %l-arginine. After consuming the diets for 7 d, six pigs were randomly selected from each group to obtain various tissues. Compared with control pigs, dietary supplementation with 1 %l-arginine did not affect feed intake but enhanced (P < 0·05) the relative weight of the small intestine (+33 %), daily BW gain (+38 %) and feed efficiency (+28 %). The villus height of the duodenum, jejunum and ileum in arginine-supplemented piglets was 21, 28 and 25 % greater (P < 0·05) than in the non-supplemented control group. Arginine supplementation increased (P < 0·05) protein levels for vascular endothelial growth factor (VEGF) in duodenal, jejunal and ileal mucosae by 14, 39 and 35 %, respectively. Compared with the control group, dietary supplementation with 1 %l-arginine increased (P < 0·05) plasma concentrations of arginine and insulin (+36 %), and decreased (P < 0·05) plasma concentrations of cortisol ( − 33 %), NH3( − 21 %) and urea ( − 19 %). These results indicate that arginine supplementation enhances intestinal growth, development and expression of VEGF in early-weaned pigs fed a maize- and soyabean meal-based diet. The findings may have important implications for neonatal pigs under stressful or diseased conditions.
White House Issues Scientific Integrity Policies
Authors: Showstack Randy 
Published: January 2011

On 17 December the White House issued its long‐awaited guidelines on the Obama administration's scientific integrity policy.The new memorandum to heads of departments and agencies of the U.S. federal government “describes the minimum standards expected as departments and agencies craft scientific integrity rules appropriate for their particular missions and cultures, including a clear prohibition on political interference in scientific processes and expanded assurances of transparency,” according to Presidential Science Advisor John Holdren, who released the guidelines. Holdren also is the director of the White House Office of Science and Technology Policy (OSTP). The guidelines require “that department and agency heads report to me on their progress toward completing those rules within 120 days.”
Kinetics and mechanistic analysis of an extremely rapid carbon dioxide fixation reaction
Authors: Huang Deguang , Makhlynets Olga V. , Tan Lay Ling , Lee Sonny C. , Rybak-Akimova Elena V. , Holm R. H. 
Published: January 2011

Carbon dioxide may react with free or metal-bound hydroxide to afford products containing bicarbonate or carbonate, often captured as ligands bridging two or three metal sites. We report the kinetics and probable mechanism of an extremely rapid fixation reaction mediated by a planar nickel complex [Ni
II
(NNN)(OH)]
1-
containing a tridentate 2,6-pyridinedicarboxamidate pincer ligand and a terminal hydroxide ligand. The minimal generalized reaction is M-OH + CO
2
→ M-OCO
2
H; with variant M, previous rate constants are ≲10
3
M
-1
s
-1
in aqueous solution. For the present bimolecular reaction, the (extrapolated) rate constant is 9.5 × 10
5
M
-1
s
-1
in N,N′-dimethylformamide at 298 K, a value within the range of
k
cat
/
K

M

≈10
5
–10
8
M
-1
s
-1
for carbonic anhydrase, the most efficient catalyst of CO
2
fixation reactions. The enthalpy profile of the fixation reaction was calculated by density functional theory. The initial event is the formation of a weak precursor complex between the Ni-OH group and CO
2
, followed by insertion of a CO
2
oxygen atom into the Ni-OH bond to generate a four center Ni(
η
2
-OCO
2
H) transition state similar to that at the zinc site in carbonic anhydrase. Thereafter, the Ni-OH bond detaches to afford the Ni(
η
1
-OCO
2
H) fragment, after which the molecule passes through a second, lower energy transition state as the bicarbonate ligand rearranges to a conformation very similar to that in the crystalline product. Theoretical values of metric parameters and activation enthalpy are in good agreement with experimental values [Δ
H
‡
= 3.2(5) kcal/mol].
Genome-Wide Analysis of Light-Dependent Transcript Accumulation Patterns during Early Stages of Arabidopsis Seedling Deetiolation
Authors: Peschke Florian , Kretsch Thomas 
Published: January 2011

AbstractLight is among the most important exogenous factors that regulate plant development. To sense light quality, intensity, direction, and duration, plants have evolved multiple photoreceptors that enable the detection of photons from the ultraviolet B (UV-B) to the far-red spectrum. To study the effect of different light qualities on early gene expression, dark-grown Arabidopsis (Arabidopsis thaliana) seedlings were either irradiated with continuous far-red, red, or blue light or received pulses of red, UV-A, or UV-A/B light. The expression profiles of seedlings harvested at 45 min and 4 h were determined on a full genome level and compared with the profiles of dark controls. Data were used to identify light-regulated genes and to group these genes according to their light responses. While most of the genes were regulated by more than one light quality, a considerable number of UV-B-specific gene expression responses were obtained. An extraordinarily high similarity in gene expression patterns was obtained for samples that perceived continuous irradiation with either far-red or blue light for 4 h. Mutant analyses hint that this coincidence is caused by a convergence of the signaling cascades that regulate gene expression downstream of cryptochrome blue light photoreceptors and phytochrome A. Whereas many early light-regulated genes exhibited uniform responses to all applied light treatments, highly divergent expression patterns developed at 4 h. These data clearly indicate that light signaling during early deetiolation undergoes a switch from a rapid, but unspecific, response mode to regulatory systems that measure the spectral composition and duration of incident light.
The application of risk and disease modelling to emerging freshwater diseases in wild aquatic animals
Authors: THRUSH MARK A. , MURRAY ALEXANDER G. , BRUN EDGAR , WALLACE STUART , PEELER EDMUND J. 
Published: January 2011

Summary1. Emerging diseases pose significant ecological and economic threats in fresh waters. Both risk assessment and mathematical modelling have potential to improve our understanding of the uncertainties associated with emerging disease events and make informed predictions about their likely impact.2. We review the different methodologies that may be used to estimate the likely geographic spread and potential impact of new and emerging diseases in fresh waters. We also highlight the limitations of the currently available methods and requirements for future development.3. In the realm of aquatic animal health, risk assessment has been used mainly to examine the risks of disease spread through international trade import risk analysis (IRA). Import risk analysis of newly emerged diseases underpins the development of appropriate risk mitigation measures to minimise further spread. This is best illustrated by assessments of the spread of Gyrodactylus salaris and also illustrates how risk assessment can examine disease interaction between wild and farmed fish.4. Various approaches have been employed to study disease transmission within freshwater fish populations at a range of spatial scales. There is scope for the application of these techniques to predict the impact of economically and environmentally important emerging freshwater diseases that arise from new pathogens, known diseases spreading to new locations or changes in pathogenicity owing to changing environmental conditions (e.g. because of climate change).5. Population models are widely used in freshwater fishery management. The integration of disease processes within freshwater aquatic animal population models is required to provide tools to assess the likely impact of newly emerged diseases and allow mitigation measures to be assessed.6. Compared with their use in other areas of animal health, modelling has been relatively little used for aquatic animal disease studies. The wide range of modelling methods used to study disease in human and terrestrial animals can usefully be applied to inform the development of policies to protect the health of wild stocks from emerging diseases.
The relationship between selected developmental assets and health‐promoting behaviours of adolescents in Southern Taiwan
Authors: Wang Ruey‐Hsia , Chen Shu‐Wen , Tang Shan‐Mei , Lee Shu‐Li , Jian Shu‐Yuan 
Published: January 2011

Aims and objectives.  To examine the relationship between selected developmental assets and health‐promoting behaviours of adolescents.Background.  Developmental assets can be considered as potential health assets for adolescents. Understanding the relationship between developmental assets and health‐promoting behaviours among adolescents could provide nurses with a new approach to design intervention programmes for adolescent health‐promoting behaviours.Design.  A cross‐sectional study design.Methods.  Anonymous questionnaires were administered to 453 adolescents aged between 13–16 years. Canonical correlation analysis was used to examine the relationship between selected developmental assets and health‐promoting behaviours.Results.  Canonical correlation analysis indicated two significantly meaningful variate pairs between selected developmental assets and health‐promoting behaviour sets. The first pair variate accounted for 51·3% of the total variance, which showed that adolescents who had better self‐esteem, future aspirations, responsible choices, family communication, non‐parental adult role models, peer role models and community involvement had better behaviours of life appreciation, health responsibility, social support, stress management, nutrition and exercise. The second pair variate accounted for 9·6% of the total variance, which showed that adolescents who had better responsible choices had better stress management behaviours.Conclusion.  Developmental assets are important to adolescents’ health‐promoting behaviours. Interventions focusing on strengthening developmental assets can potentially provide an innovative approach for nurses to improve health‐promoting behaviours of adolescents.Relevance to clinical practice.  Strengthening developmental assets can potentially improve the health‐promoting behaviours of adolescents. Individual and sociopolitical domains should be incorporated into programmes for enhancement of developmental assets. School nurses can cooperate with family and community and provide environments improving adolescents’ developmental assets. Nurses should actively engage in developmental asset programmes for adolescents. The tools for measuring developmental assets modified and developed in this study were valid and reliable. They can be used for further examination of the developmental assets for adolescents in various subset populations.
A psychometric evaluation of the Taiwan version of the Individual Workload Perception Scale
Authors: Lin Shu‐Yuan , Lin Chung‐Hui , Yeh Mei Chang , Lin Shu‐Ying , Hwang Yueh‐Jiau 
Published: January 2011

Aim. The aim was to evaluate the psychometric properties of the Taiwan version of the Revised Individual Workload Perception Scale on staff nurses in southern Taiwan.Background. Most psychometric measures of the nursing work environment were developed in North America and reflect nursing practice in Western health care environments. As these instruments are used most often in translation, it is important to inquire whether they appropriately capture the characteristics of nursing work in environments outside of the original contexts.Design. A descriptive, cross‐sectional study was conducted between 1 June–30 September 2009, with a convenience sample of 344 nurses providing direct patient care at a regional teaching hospital in southern Taiwan. The Taiwan version of the Revised Individual Workload Perception Scale was created by translating the original English language Individual Workload Perception Scale–Revised, which is used to measure the staff nurses’ perceptions of their work environment. The Taiwan version of the Revised Individual Workload Perception Scale is a 24‐item five‐point Likert scale measuring manager support, peer support, unit support, workload and intent to stay. Content validity, construct validity and reliability of the Taiwan version of the Revised Individual Workload Perception Scale were evaluated.Results. The content validity index of the Taiwan version of the Revised Individual Workload Perception Scale was 0·93. Cronbach’s alpha for the total Taiwan version of the Revised Individual Workload Perception Scale was 0·88, with a range of 0·61–0·85 for the subscales. Factorial validity was supported using a five‐factor model solution that accounted for 55·47% of the total variance for nursing work environment. Manager support had the highest explained variance (28·38%).Conclusions. Acceptable reliability and content validity were found; the Taiwan version of the Revised Individual Workload Perception Scale is recommended for measuring nurses’ perceptions of their work environment.Relevance to clinical practice. Psychometric properties of a scale such as the Individual Workload Perception Scale translate cross‐culturally, with minor adjustments. The Taiwan version of the Revised Individual Workload Perception Scale can be used to provide data and analyses in comparisons with nursing work environment features internationally.
Efficacy of controlling night‐time noise and activities to improve patients’ sleep quality in a surgical intensive care unit
Authors: Li Shu‐Yen , Wang Tsae‐Jyy , Vivienne Wu Shu F , Liang Shu‐Yuan , Tung Heng‐Hsin 
Published: January 2011

Aim.  The aim of the study was to test the efficacy of sleep care guidelines for controlling night‐time noise and improving sleep quality of patients in a surgical intensive care unit.Background.  Poor sleep quality places critically ill patients at greater risk for infection, complications and mortality. Environmental stimuli such as noises, continuous lighting and frequent care‐related activities in an intensive care unit interfere with patients’ sleep.Design.  The study used a quasi‐experimental design.Method.  Sixty surgical patients were recruited from an intensive care unit in Taiwan during December 2007–May 2008. The control group received the usual care, and the experimental group was cared for by nurses who followed the sleep care guidelines for noise and light reduction. Data were collected on noise level and sleep quality using the Sleep in the Intensive Care Unit Questionnaire, the Richards Campbell Sleep Questionnaire and a decibel meter.Results.  The results showed that both the peak sound level (χ2 = 50·1, p < 0·001) and average noise level (χ2 = 46·5, p < 0·001) were reduced significantly, after implementing the guidelines. The perceived noise (t = −2·07, p = 0·046) and sleep interruptions from care‐related activities (t = 5·282, p < 0·001) and noises (t = 4·361, p < 0·001) were all significantly lower in the experimental group than in the control group. The experimental group also reported better sleep quality (t = −2·28, p = 0·027) and sleep efficiency (t = −2·03, p = 0·047) than did the control group.Conclusions.  These results support the efficacy of the guidelines for controlling night‐time noise and care activities to improve patients’ sleep quality.Relevance to clinical practice.  Nurses should try to reduce external environmental stimuli and maintain an almost undisturbed period between midnight and 5:00 a.m. to enhance patients’ sleep in a surgical intensive care unit.
Conflict management styles used by nurse managers in the Sultanate of Oman
Authors: Al‐Hamdan Zaid , Shukri Raghda , Anthony Denis 
Published: January 2011

Aim.  The study aimed at investigating the conflict management styles used by nurse managers in the Sultanate of Oman.Background.  Conflict is inevitable in daily nursing work. Several styles are used to manage conflict situations. In previous studies conducted in Western countries, avoiding and compromising conflict management styles appear to be the first choices for the nurses. In Arab countries, no study to date has examined the conflict management styles used by nurse managers to compare with the results from studies conducted in Western countries.Design.  Survey.Method.  A questionnaire was distributed to all nurse managers working in the three‐management levels from nine referral hospitals in Sultanate of Oman, 271 were returned, a response rate of 86%. The results were analysed using spss version 16.Results.  Nurse managers in Oman used all five conflict management styles, with integrating style as the first choice followed in order by compromising, obliging, dominating and avoiding. These results differ from the results of the studies conducted on nurses in other countries.Conclusion.  The results of this study have implications for people who work in the hospitals, whether practitioners or policy makers. Recommendations are offered to improve nurse managers’ work environment.Relevance to clinical practice.  Conflict can affect patient care if handled badly. Poorly handled conflict results in lower staff morale and poorer retention, both adversely affect patient care.