bluuebunny/crossref_metadata_2025 huggingface dataset:
Meiotic abnormalities underlying pollen sterility in wild potato hybrids and spontaneous populations
Authors: Larrosa F. H. , Maune J. F. , Erazzú L. E. , Camadro E. L.
Published: May 2011

Wild potato species are widely distributed in the Americas, where they spontaneously grow in very diverse habitats. These species – with low chromosome differentiation – form polyploid series with 2n = 2x, 3x, 4x and 6x (x = 12). They are isolated in nature by external and internal hybridisation barriers that can be incomplete, allowing hybridisation in areas of sympatry. Nevertheless, most accessions in germplasm banks, regardless of genetic background of the sampled spontaneous populations, have been assigned specific categories based on morphological characters. To further investigate the extent of hybridisation in the group and for comparative purposes, pollen viability was estimated in (i) artificial hybrids between a commercial cultivar (Calén INTA) of the common potato (tetraploid Solanum tuberosum ssp. tuberosum) and the tetraploid cytotype of the related wild species S. gourlayi, and (ii) samples of plants (accessions) and inflorescences of natural populations from Argentina, tentatively classified as ‘presumed hybrids’ (S. infundibuliforme–S. gourlayi) and ‘species’ (S. infundibuliforme, S. gourlayi and S. chacoense). Regardless of origin, 98 out of 103 plants analysed had zero to 70% pollen viability (zero to 40% in eight of them). Pollen grains were of variable size and morphology and, in mostly male sterile plants, the only viable pollen grains were 2n and/or 4n. Furthermore, male sterile plants shared various abnormalities in meiosis I and II (unpaired chromosomes, unequal chromosome distribution, precocious/lagging chromosomes, parallel, tripolar, fused and multiple spindles, unequal size nuclei, dyads, triads and pentads in addition to normal tetrads, among others). These results provide novel evidence to support field observations of early potato botanists on the extent of spontaneous hybridisation in wild Argentinian potato populations, which is not reflected in the current taxonomy and has significant consequences for germplasm conservation and breeding.
Digestible energy content of pasture species in growing European wild boar (Sus scrofa L.)
Authors: Quijada R. P. , Bitsch N. I. , Hodgkinson S. M.
Published: May 2011

The objectives were to determine the apparent energy digestibility of six pasture species frequently grazed by European wild boar (Sus scrofa L.) and to estimate the digestible energy (DE) consumption from pasture by grazing wild boar. Seven diets were prepared; a base diet (BD) which did not contain any pasture species, diets D1 to D5 which included 75% of the BD and 25% of the dried pasture species Lolium perenne (D1), Festuca arundinacea (D2), Agrostis capillaris (D3), Bromus staminius (D4) or Trifolium repens (D5) and D6 which contained 85% BD and 15% dried Plantago lanceolata. Seven purebred European wild boar (initial liveweight 24.4 ± 0.8 kg, average ± SEM) were given access to the diets following a Latin Square design. The animals received each diet for eight days, with faecal sampling on days 6, 7 and 8. The total apparent DE consumption from pasture by grazing wild boar was estimated using previously collected pasture consumption data from wild boar. The digestibility coefficients and DE contents of the pasture species ranged from 0.29 to 0.65, and 5.8 to 12.6 MJ/kg DM respectively, with L. perenne and P. lanceolata having the greatest digestibility coefficients and DE contents. The wild boar were estimated to satisfy between 52% and 142% of their maintenance energy requirements through pasture consumption. Grazing wild boar are able to utilise an important proportion of the energy present in pasture species.
Heat shock protein 27 and cyclophilin A associate with the pathogenesis of COPD
Authors: HU RUICHENG , OUYANG QING , DAI AIGUO , TAN SHUANGXIANG , XIAO ZHIQIANG , TANG CENE
Published: May 2011

Background and objective:  COPD is a global disease characterized by chronic bronchitis and obstructive emphysema. Its pathogenesis is not fully understood. This study aimed to use proteomics to provide new insights into the mechanisms of COPD.

Methods:  Protein lysates were prepared from lung tissue samples harvested from never‐smokers, non‐COPD smokers and COPD smokers, and were analysed using 2‐dimensional gel electrophoresis. Differentially expressed proteins were identified using mass spectrometry. The differential expression of heat shock protein 27 (Hsp27) and cyclophilin A (CyPA) was validated by immunohistochemistry and western blotting.

Results:  Twenty‐four proteins were identified by mass spectrometry as being differentially expressed among the three groups of subjects. The main functions of these proteins involve basic metabolism, oxidation/reduction, coagulation/fibrinolysis, protein degradation, signal transduction, inflammation and cell growth/differentiation/apoptosis. Proteomic analysis revealed that the expression of Hsp27 and CyPA was upregulated in smokers, and this upregulation was particularly marked in COPD smokers. The variation in expression of Hsp27 and CyPA between the groups was confirmed by immunohistochemistry and western blotting.

Conclusions:  Hsp27 and CyPA are associated with the pathogenesis of COPD, and smoking contributes to the overexpression of these proteins.
Are psyllids affiliated with the threatened plants Acacia ausfeldii, A. dangarensis and A. gordonii at risk of co‐extinction?
Authors: POWELL FIONA A. , HOCHULI DIETER F. , SYMONDS CELIA L. , CASSIS GERASIMOS
Published: May 2011

Secondary extinctions of dependent affiliate species may exceed the numbers of species directly extirpated with habitat loss. We investigated the host specificity, and hence the co‐extinction risk, of multiple psyllid species (Hemiptera: Psylloidea) on the threatened plants Acacia ausfeldii, A. dangarensis and A. gordonii by sampling from these and other sympatric common plants across multiple sites, years and plant phenologies. We found one specialist psyllid species (Psyllidae: Acizzia sp.) on each of the plants A. ausfeldii and A. gordonii but no specialists on A. dangarensis. The A. gordonii specialist only occurred when its host was in flower. Specialist psyllids considered at risk of extinction represented 10% of all psyllid species observed on the three threatened acacias. Potential risks to co‐endangered affiliates need to be considered when implementing threatened plant recovery actions. Conservation of plant populations and plant species diversity is also necessary to maintain high insect diversity.
Health‐related quality of life after surgery for primary advanced rectal cancer and recurrent rectal cancer: a review
Authors: Thaysen H. V. , Jess P. , Laurberg S.
Published: May 2011

Aim  Health‐related quality of life is an important outcome measure in treatment of cancer. A review of the literature was undertaken to provide an overview of health‐related quality of life (HRQoL) after surgery for primary advanced or recurrent rectal cancer and to outline proposals for future HRQoL studies in this area.

Method  A systematic literature search was undertaken. Only studies concerning surgery for primary advanced or recurrent rectal cancer and describing methods used for measuring HRQoL were considered.

Results  Seven studies were identified, including two prospective longitudinal studies, three cross‐sectional studies and two based on qualitative data. Global quality of life, and physical, social, role and sexual function seemed to be impaired for a varying time after surgery. All the studies had methodical problems due to small sample size (12–44 patients) and different points of time for the assessment of HRQoL (12.3–47 months), which made it difficult to determine the period of time of impaired HRQoL and also if this is different after surgery for locally advanced or recurrent disease compared with after total mesorectal excision used for earlier tumours.

Conclusion  Several aspects of HRQoL are impaired for a variable time after treatment for locally advanced or recurrence of rectal cancer. Larger prospective longitudinal studies are needed to provide further information regarding the effects of this extensive surgery on quality of life.
Investigating Chinese University Students’ Knowledge of and Attitudes Toward Plagiarism From an Integrated Perspective
Authors: Hu Guangwei , Lei Jun
Published: May 2011

This article reports on a mixed‐methods study of Chinese university students’ knowledge of and attitudes toward plagiarism in English academic writing. A sample of 270 undergraduates from two Chinese universities rated three short English passages under different conditions, provided open‐ended responses to justify their ratings, and completed a written questionnaire. The rating tasks were designed to determine their ability to recognize two forms of intertextuality (i.e., unacknowledged copying and paraphrasing) generally regarded as plagiarism in Anglo‐American academia. The questionnaire was administered to collect self‐appraisals of competence in source use and to assess declarative knowledge of intertextual practices that match typical Anglo‐American definitions of blatant and subtle plagiarism. Qualitative and quantitative analyses revealed that a minority of the students recognized the two forms of plagiarism and generally took a punitive attitude toward the detected cases of plagiarism. Further quantitative analyses found that discipline, self‐reported competence in referencing, and knowledge of subtle plagiarism were consistently significant predictors of successful plagiarism detection. These findings raise questions about some culturally based interpretations of plagiarism and point to the need to take a nuanced approach to plagiarism in L2 writing.
Is non‐ablative 1550‐nm fractional photothermolysis an effective modality to treat melasma? Results from a prospective controlled single‐blinded trial in 51 patients
Authors: Karsai S. , Fischer T. , Pohl L. , Schmitt L. , Buhck H. , Jünger M. , Raulin C.
Published: May 2011

Background  Melasma is a common benign pigmentary disease and can pose a substantial therapeutic challenge. Although the use of non‐ablative fractional photothermolysis (NFP) has gained much popularity, there are still very few evidence‐based data supporting NFP in the treatment of melasma.

Objective  To assess the efficacy and safety of NFP for the treatment of melasma in a controlled observer‐blinded parallel‐group study.

Patients and methods  Fifty‐one patients [90.2% women, 9.8% men; mean age 40.3 ± 6.1 (control group) and 41.7 ± 11.4 (treatment group)] received a broad‐spectrum sunscreen either alone (n = 25; 49.0%) or in combination with a 1550‐nm NFP treatment (n = 26; 51.0%) [energy: 15 mJ/microthermal zone (MTZ); total density: 1048 MTZs/cm2; density per pass: 131 MTZs/cm2; number of passes: 8; total coverage: 20%]. Four sessions of NFP treatment were performed at 3‐week intervals on each subject in the treatment group. Patients were evaluated at baseline and 12 weeks after final treatment. The primary efficacy variables were the Melasma Area and Severity Index (MASI) and the physician’s global assessment (PGA); secondary efficacy variables were the patients’ subjective assessment of improvement and patient satisfaction. Safety was evaluated through the reporting of adverse events.

Results  The percentage of subjective improvement was virtually identical in both groups: one‐third of the patients reported a ‘marked improvement’ and another half reported ‘some improvement’. Twenty‐three patients in each group declared that they were ‘satisfied’ with the treatment result. The MASI corroborated the patients’ subjective estimate, both in terms of the degree of improvement and the lack of a group difference. In both groups, the MASI score and the PGA were reduced significantly after therapy, and the reduction was also clinically relevant. No serious side‐effects were reported in either group.

Conclusion  Our findings do not support the hypothesis of NFP providing a substantial benefit in treating melasma when compared with the lone application of a broad‐spectrum sunscreen.
Infantile haemangioma: Part I. Pathophysiology, epidemiology, clinical features, life cycle and associated structural abnormalities
Authors: Léauté‐Labrèze C. , Prey S. , Ezzedine K.
Published: May 2011

Infantile haemangioma (IH) is the most common tumour of infancy. Its typical natural history is characterized by an early rapid growth following birth and a slow spontaneous regression phase within a period of 3 to 7 years. The exact aetiopathogeny underlying IH is still to be fully understood, but the role of fetal hypoxic stress is strongly suggested as a triggering signal in epidemiological studies. IH are composed of a complex mixture of cells including multipotent stem cells, a majority of immature endothelial cells, pericytes, dendritic cells and in the late stage, adipocytes. Most of IH are nodular and are not associated with malformations. However, in some cases, IH referred to as segmental may be associated with developmental abnormalities such as PHACES and PELVIS/SACRAL syndromes.
Infantile haemangioma: Part II. Risks, complications and treatment
Authors: Léauté‐Labrèze C. , Prey S. , Ezzedine K.
Published: May 2011

Because of their spontaneous involution, most infantile haemangiomas (IH) do not require therapeutic intervention. However, in 10 to 15% of cases such as segmental and multifocal IH, locations in the periocular, airway and perineal areas, or complications of ulceration, treatment is necessary. Moreover, the risk of permanent scarring and disfigurement associated with IH, even if involution is complete, has been increasingly recognized as a rationale for treatment. Treatments for IH currently include topical, intralesional, systemic therapies, laser and surgical modalities depending on the clinical scenario. However, clinicians must carefully weigh the risks and benefits for each treatment. Recently, the efficacy of propranolol, a non‐cardioselective beta‐blocker, was reported and has been revolutionary in the management of IH.
Psoriasis and hypertension: a case‐control study
Authors: Armesto S. , Coto‐Segura P. , Osuna C.G. , Camblor P.M. , Santos‐Juanes J.
Published: May 2011

Background  Several studies stated that patient with psoriasis carried an increased risk of psoriasis but some studies did not demonstrate this association.

Objectives  The aim of this study was to evaluate the prevalence of hypertension in psoriasis based on a sample of Spanish population.

Methods  This was a hospital‐based case‐control study involving 661 psoriatic patients (cases) and 661 control matched by gender and age. Meta‐analysis of the previous studies was made.

Results  The prevalence of hypertension was significantly higher in psoriasis patients than controls (30.3%, 21.3%, respectively, P < 0.001). In a multivariate analysis, hypertension was associated with psoriasis after controlling for age, gender, diabetes, obesity and smoking (OR = 1.44, 95% confidence interval: 1.07–1.94).

Conclusion  The results of this study support the association between psoriasis and hypertension.
Quality‐of‐care for leg ulcers in the metropolitan area of Hamburg – a community‐based study
Authors: Herberger K. , Rustenbach S.J. , Grams L. , Münter K.C. , Schäfer E. , Augustin M.
Published: May 2011

Background  Diagnosis and therapy of chronic wounds constitute an interdisciplinary challenge and should be oriented on the guideline standards. Although no data on the quality‐of‐care are available for Germany, it can be concluded from qualitative estimates and expert reports that the majority of patients are not receiving adequate treatment.

Objectives  Evaluation of the quality‐of‐care for leg ulcers in the metropolitan area of Hamburg by means of newly developed guideline‐based indicators.

Methods  Leg ulcer patients of any aetiology were consecutively included. The spectrum of 220 health‐care providers ranged from wound clinics, office‐based practices, nursing homes to home‐care services and doss houses. The survey included a clinical examination and the completion of questionnaires covering quality of life, experiences with treatment and quality of health care.

Results  A total of 520 patients with leg ulcers were included. Among these patients, 63% were of venous, 23% of mixed, 2% of vasculitic and 12% of other origin; 78.6% of the patients were treated with moist wound dressings. Pain therapy was performed in 54.1%, compression therapy in 53.5%. Shortcomings were noted in the diagnostic work‐up and in concomitant wound care such as physiotherapy. Around 70% displayed marked to profound impairment in quality of life. The quality‐of‐care index showed that 64% of the indicators were met by the actual care; 61.8% of the patients exhibiting a sufficient quality‐of‐care, regardless of age, social status, place of abode or insurance status.

Conclusions  Although the majority of patients received adequate therapy, many patients are not being treated properly in accordance with the guidelines.
Topical immunotherapy with diphenylcyclopropenone of patients with alopecia areata – a large retrospective study on 142 patients with a self‐controlled design
Authors: Ohlmeier M.C. , Traupe H , Luger T.A , Böhm M
Published: May 2011

Background  Although diphenylcyclopropenone (DCP) is frequently used for the treatment of alopecia areata (AA), large studies with more than 100 patients are still scarce.

Objective  To determine the efficacy of DCP immunotherapy in a large cohort of patients with AA who had been treated in our institute from January 2000 to December 2006.

Methods  A total of 142 patients with AA undergoing topical DCP therapy in a self‐controlled design were evaluated retrospectively.

Results  Seven patients (4.9%) were anergic to DCP. Two of 135 patients (1.5%) discontinued DCP therapy because of adverse effects. Fifty‐one patients (37.8%) had a complete response (CR: >90% re‐growth of hair), 20 patients (14.8%) exhibited a partial response (PR: >50–90% re‐growth), 26 patients (19.3%) experienced a minimal response (MR: 10–50% re‐growth) and 38 patients (28.1%) had no response after DCP therapy (NR: <10% re‐growth). Bivariate logistic analysis revealed that severity of hair loss at the beginning of DCP (P = 0.001) is the only significant prognostic factor for therapeutic outcome. Twenty‐three patients (45.1%) with CR had relapses upon discontinuation of the treatment or even during prolonged DCP therapy.

Conclusion Topical immunotherapy with DCP of patients with AA is rather effective and mostly well tolerated. The extent of hair loss before therapy is the main predictor for the therapeutic success of DCP. However, DCP therapy is associated with a high degree of relapse of which patients should be well informed.
A novel heterozygous nonsense mutation of keratin 5 in a chinese family with Dowling–Degos disease
Authors: Guo L. , Luo X , Zhao A , Huang H , Wei Z , Chen L , Qin S , Shao L , Xuan J , Feng G , Minghua C , Luan J. , He L , Xing Q
Published: May 2011

Background  Dowling–Degos disease (DDD; MIM 179850) is an autosomal dominant genodermatosis caused by mutations in keratin 5 gene (KRT5). KRT5 is specifically expressed in basal layer of epidermis and plays an important role in protecting epithelial cells from mechanical and non‐mechanical stresses.

Objective  We analysed the molecular basis of DDD in a Chinese family.

Methods  Genomic DNA of the Chinese DDD family and a matched control cohort was isolated according to standard techniques. All exons of the KRT5 gene and adjacent exon–intron border sequences were amplified using PCR and directly sequenced.

Results  We identified a novel keratin 5 (K5) nonsense mutation designated c.C10T (p.Gln4X) in exon 1 of the KRT5 gene.

Conclusion  Our data expand the spectrum of mutations in the KRT5 gene underlying DDD.
Transition from wind pollination to insect pollination in sedges: experimental evidence and functional traits
Authors: Wragg Peter D. , Johnson Steven D.
Published: May 2011

See also the Commentary by Friedman
Global diversity in light of climate change: the case of ants
Authors: Jenkins Clinton N. , Sanders Nathan J. , Andersen Alan N. , Arnan Xavier , Brühl Carsten A. , Cerda Xim , Ellison Aaron M. , Fisher Brian L. , Fitzpatrick Matthew C. , Gotelli Nicholas J. , Gove Aaron D. , Guénard Benoit , Lattke John E. , Lessard Jean‐Philippe , McGlynn Terrence P. , Menke Sean B. , Parr Catherine L. , Philpott Stacy M. , Vasconcelos Heraldo L. , Weiser Michael D. , Dunn Robert R.
Published: May 2011

Aim  To use a fine‐grained global model of ant diversity to identify the limits of our knowledge of diversity in the context of climate change.

Location  Global.

Methods  We applied generalized linear modelling to a global database of local ant assemblages to predict the species density of ants globally. Predictors evaluated included simple climate variables, combined temperature × precipitation variables, biogeographic region, elevation, and interactions between select variables. Areas of the planet identified as beyond the reliable prediction ability of the model were those having climatic conditions more extreme than what was represented in the ant database.

Results  Temperature was the most important single predictor of ant species density, and a mix of climatic variables, biogeographic region and interactions between climate and region yielded the best overall model. Broadly, geographic patterns of ant diversity match those of other taxa, with high species density in the wet tropics and in some, but not all, parts of the dry tropics. Uncertainty in model predictions appears to derive from the low amount of standardized sampling of ants in Asia, in Africa and in the most extreme (e.g. hottest) climates. Model residuals increase as a function of temperature. This suggests that our understanding of the drivers of ant diversity at high temperatures is incomplete, especially in hot and arid climates. In other words, our ignorance of how ant diversity relates to environment is greatest in those regions where most species occur – hot climates, both wet and dry.

Main conclusions  Our results have two important implications. First, temperature is necessary, but not sufficient, to explain fully the patterns of ant diversity. Second, our ability to predict ant diversity is weakest exactly where we need to know the most, the warmest regions of a warming world. This includes significant parts of the tropics and some of the most biologically diverse areas in the world.
A randomized multicenter trial of Crotalidae polyvalent immune Fab antivenom for the treatment of rattlesnake envenomation in dogs
Authors: Peterson Michael E. , Matz Michael , Seibold Karen , Plunkett Signe , Johnson Scott , Fitzgerald Kevin
Published: May 2011

Objective
–
To determine clinical efficacy of the Crotalidae polyvalent immune Fab (ovine) antivenom (OPCA) against progressive crotalid envenomation in the dog as reflected in stabilization or improvement of snakebite severity scores (SSS). Additionally, due to the potential decreased half‐life of the Fab antibodies in dogs we compared SSS between dogs receiving 2 different dosing regimes.

Design
–
Prospective, clinical trial.

Setting
–
Five veterinary emergency and critical care facilities.

Animals
–
One hundred and fifteen client‐owned Crotalid (rattlesnake) snake bitten dogs in whom worsening of the envenomation syndrome was observed before OPCA treatment.

Interventions
–
In a multicenter randomized clinical trial a single dose (1 vial) of OPCA alone was compared with 2 doses (1/2 vial each) administered 6 hours apart. Standard supportive care was provided in all cases.

Measurements and Main Results
–
Data were available for 115 patients, 9 of which were fatalities. All patients' clinical condition was documented with a standardized SSS system accounting for each major body system. Each fatality received maximum severity scores of 20. The mean severity score of the 115 patients decreased from 4.19 to 3.29 points and there was no difference between the 2 treatment groups. The mean severity score of the 107 patients without fatalities decreased from 4.16 to 2.15. Antivenin‐related acute reactions occurred in 6 dogs (6%), and no serum sickness occurred within the 95 cases contacted at the 2‐week posttreatment follow‐up.

Conclusions
–
In the first randomized trial in dogs of antivenin in the United States, OPCA effectively stabilized or terminated venom effects. There were no statistical differences detected between treatment groups within the study time frame.
Neutral Lipid Storage Disease with Unusual Presentation: Report of Three Cases
Authors: Singh Smita , Sharma Sunita , Agarwal Shilpi , Nangia Anita , Chander Ram , Varghese Bincey
Published: May 2011

Abstract:  Neutral lipid storage disease is a nonlysosomal multisystemic triglyceride storage disease. It is characterized by leukocyte vacuolization (Jordans’ anomaly), variable systemic involvement, and ichthyosis. Two of our patients presented with congenital ichthyosis. Lipid vacuoles were demonstrated in granulocytes and monocytes and in basal keratinocytes on skin biopsy. They were diagnosed as Chanarin Dorfman syndrome. In contrast to these cases, the third case presented with progressive symmetric erythrokeratoderma without ichthyosis. Lipid vacuoles were demonstrated in blood cells on peripheral smear and in basal keratinocytes. Only screening of peripheral smear led to the correct diagnosis.
N‐glycosylation influences the structure and self‐association abilities of recombinant nucleolin
Authors: Losfeld Marie‐Estelle , Leroy Arnaud , Coddeville Bernadette , Carpentier Mathieu , Mazurier Joël , Legrand Dominique
Published: May 2011

Nucleolin is a major nucleolar protein involved in fundamental processes of ribosome biogenesis, regulation of cell proliferation and growth. Nucleolin is known to shuttle between nucleus, cytoplasm and cell surface. We have previously found that nucleolin undergoes complex N‐ and O‐glycosylations in extra‐nuclear isoforms. We found that surface nucleolin is exclusively glycosylated and that N‐glycosylation is required for its expression on the cells. Interestingly, the two N‐glycans are located in the RNA‐binding domains (RBDs) which participate in the self‐association properties of nucleolin. We hypothesized that the occupancy of RBDs by N‐glycans plays a role in these self‐association properties. Here, owing to the inability to quantitatively produce full‐size nucleolin, we expressed four N‐glycosylation nucleolin variants lacking the N‐terminal acidic domain in a baculovirus/insect cell system. As assessed by heptafluorobutyrate derivatization and mass spectrometry, this strategy allowed the production of proteins bearing or not paucimannosidic‐type glycans on either one or two of the potential N‐glycosylation sites. Their structure was investigated by circular dichroism and fluorimetry, and their ability to self‐interact was analyzed by electrophoresis and surface plasmon resonance. Our results demonstrate that all nucleolin‐derived variants are able to self‐interact and that N‐glycosylation on both RBD1 and RBD3, or RBD3 alone, but not RBD1 alone, modifies the structure of the N‐terminally truncated nucleolin and enhances its self‐association properties. In contrast, N‐glycosylation does not modify interaction with lactoferrin, a ligand of cell surface nucleolin. Our results suggest that the occupancy of the N‐glycosylation sites may contribute to expression and functions of surface nucleolin.

Structured digital abstract

 NCT binds to NCT by surface plasmon resonance (View interaction)

 R3CT binds to R3CT by surface plasmon resonance (View interaction)

 RCT binds to RCT by surface plasmon resonance (View interaction)

 RCT binds to RCT by blue native page (View interaction)

 NCT binds to lactoferrin by surface plasmon resonance (View interaction)

 R3CT binds to R3CT by blue native page (View interaction)
Hazardous alcohol use interventions with emergency patients: Self‐reported practices of nurses, and predictors of behaviour
Authors: Freeman Toby , Roche Ann M , Williamson Paul , Pidd Ken
Published: May 2011

Objectives: The present study examined Australian ED nurses' practices in asking patients about alcohol and assisting them to manage their alcohol consumption. It also investigated strategies to support ED nurses in these interventions.

Methods: A two‐stage survey was administered to ED nurses. The first questionnaire measured theoretical and organizational predictors of behaviour, and underlying beliefs, and the subsequent questionnaire explored rates of asking and assisting patients.

Results: A total of 125 nurses returned the first questionnaire. Participants held generally positive attitudes, perceived norms, feelings of legitimacy and perceived ability to ask about and intervene for alcohol, but lower role adequacy. The 71 ED nurses who completed the second questionnaire had intervened with almost 500 patients concerning alcohol in the previous week. Participants asked approximately one in four patients about alcohol (median = 26.3% of patients, 1095/4279 total patients asked). The Theory of Planned Behaviour did not predict rates of asking or assisting patients. Several strategies were identified that might increase rates: identify environmental factors that prevent nurses acting on their intentions to ask and intervene, raise confidence and skills, make asking about alcohol part of routine assessment, make supports such as drug and alcohol units or nurses available, and implement organizational policies on alcohol.

Conclusions: Nurses appear positively disposed to engage with patients in regard to alcohol. However, greater support is needed to achieve the considerable significant public health benefits from this engagement. The findings point to several practical strategies that could be pursued to provide this support.
A Gunn—Peterson test with a QSO at z = 6.4
Authors: Goto Tomotsugu , Utsumi Yousuke , Hattori Takashi , Miyazaki Satoshi , Yamauchi Chisato
Published: May 2011

Understanding the cosmic reionization is one of the key goals of the modern observational cosmology. High-redshift quasi-stellar object (QSO) spectra can be used as background light sources to measure the absorption by the intervening neutral hydrogen. We investigate the neutral hydrogen absorption in a deep, moderate-resolution Keck/Deimos spectrum of the QSO CFHQS J2329−0301 at z = 6.4. This QSO is one of the highest redshift QSOs presently known at z = 6.4 but is 2.5 mag fainter than a previously well-studied QSO SDSS J1148+5251 at z = 6.4. Therefore, it has a smaller Stromgren sphere and allows us to probe the highest redshift hydrogen absorption to date. The average transmitted flux at 5.915 < zabs < 6.365 (200 comoving Mpc) is consistent with zero in Lyα, Lyβ and Lyγ absorption measurements. This corresponds to the lower limit of the optical depth, ταeff > 4.9. These results are consistent with the strong evolution of the optical depth at z > 5.7.
Optimizing QSAR Models for Predicting Ligand Binding to the Drug‐Metabolizing Cytochrome P450 Isoenzyme CYP2D6
Authors: Saraceno Marilena , Massarelli Ilaria , Imbriani Marcello , James Thomas L. , Bianucci Anna M.
Published: May 2011

The cytochrome P450 isozyme CYP2D6 binds a large variety of drugs, oxidizing many of them, and plays a crucial role in establishing in vivo drug levels, especially in multidrug regimens. The current study aimed to develop reliable predictive models for estimating the CYP2D6 inhibition properties of drug candidates. Quantitative structure–activity relationship (QSAR) studies utilizing 51 known CYP2D6 inhibitors were carried out. Performance achieved using models based on two‐dimensional (2D) molecular descriptors was compared with performance using models entailing additional molecular descriptors that depend upon the three‐dimensional (3D) structure of ligands. To properly compute the descriptors, all the 3D inhibitor structures were optimized such that induced‐fit binding of the ligand to the active site was accommodated. CODESSA software was used to obtain equations for correlating the structural features of the ligands to their pharmacological effects on CYP2D6 (inhibition). The predictive power of all the QSAR models obtained was estimated by applying rigorous statistical criteria. To assess the robustness and predictability of the models, predictions were carried out on an additional set of known molecules (prediction set). The results showed that only models incorporating 3D descriptors in addition to 2D molecular descriptors possessed the requisite high predictive power for CYP2D6 inhibition.
Community Responses to a Suicidal Crisis: Implications for Suicide Prevention
Authors: Larkin Gregory Luke , Rivera Hector , Xu Hongzhi , Rincon Edward , Beautrais Annette L.
Published: May 2011

We conducted a cross‐sectional, random‐digit‐dial survey to evaluate public responses to a hypothetical question: “If someone you knew was suicidal, what would you do first?” Younger people were more likely to call a suicide hotline, and less likely to go to an emergency room (ER) or call 911; immigrants (in the U.S. <15 years) were more likely to call 911, and less likely to call a suicide hotline; African Americans were more likely to go to the ER and call 911; Hispanics were more likely to call 911 but less likely to call a suicide hotline. These results suggest that public messages about hotlines and emergency options for suicidal patients need to be tailored to relevant population characteristics including age, education, ethnicity, and language preferences.
Suicides in Users of Mental Health Care Services: Treatment Characteristics and Hindsight Reflections
Authors: Huisman Annemiek , Kerkhof Ad J.F.M. , Robben Paul B.M.
Published: May 2011

The current study aims to describe the patient and treatment characteristics of a sample of 505 suicides by mental health care patients, and to determine how clinicians view the care provided and what they learned. The results indicate that the quality of mental health care for suicidal patients could be improved by focusing on communication among clinicians, continuity of care, suicide risk assessment procedures, and the involvement of relatives.
Associations Between Types of Combat Violence and the Acquired Capability for Suicide
Authors: Bryan Craig J. , Cukrowicz Kelly C.
Published: May 2011

Research suggests that combat exposure might increase risk for suicide. The interpersonal‐psychological theory of suicide (IPTS) proposes that exposure to painful and provocative experiences such as combat contribute to fearlessness about death and increased pain tolerance, which serve to enhance the individual’s capability to attempt suicide. Violent and aggressive combat experiences, in particular, should demonstrate relatively stronger associations to this capability. The current study tests this proposition in a sample of deployed active duty combatants. Results indicate that all types of combat exposure independently contribute to capability for suicide. Consistent with the IPTS, when considering all types of combat simultaneously, combat characterized by violence and high levels of injury and death are associated with relatively stronger associations to this capability.
The Assessment and Management of Suicide Risk: State of Workshop Education
Authors: Pisani Anthony R. , Cross Wendi F. , Gould Madelyn S.
Published: May 2011

A systematic search of popular and scholarly databases identified workshops that addressed general clinical competence in the assessment or management of suicide risk, targeted mental health professionals, and had at least one peer‐reviewed publication. We surveyed workshop developers and examined empirical articles associated with each workshop. The state of workshop education is characterized by presenting the learning objectives, educational formats, instructor factors, and evaluation studies. Workshops are efficacious for transferring knowledge and shifting attitudes; however, their role in improving clinical care and outcomes of suicidal patients has yet to be determined.
Intolerance to Delayed Reward in Girls with Multiple Suicide Attempts
Authors: Mathias Charles W. , Dougherty Donald M. , James Lisa M. , Richard Dawn M. , Dawes Michael A. , Acheson Ashley , Hill‐Kapturczak Nathalie
Published: May 2011

Impulsivity has been conceptualized as influencing the expression of suicidal behavior. Adolescence is a developmental period characterized both by a relatively high rate of suicide attempts and a high level of impulsivity. The current study examined two behavioral measures (delay reward and disinhibition) and one self‐report measure of impulsivity among girls with suicide attempt histories. Girls with multiple suicide attempts performed more impulsively on measures of delayed reward, and had higher self‐ratings of depression and aggression than girls with either one or no suicide attempts. The multiple attempter girls’ preference for immediate gratification may directly increase vulnerability to suicidal acts in the context of distressing states or indirectly increase risk by creating poor life experience over time.
Prospective Predictors of Suicidality: Defeat and Entrapment Lead to Changes in Suicidal Ideation over Time
Authors: Taylor Peter James , Gooding Patricia A. , Wood Alex M. , Johnson Judith , Tarrier Nicholas
Published: May 2011

Theoretical perspectives into suicidality have suggested that heightened perceptions of defeat and entrapment lead to suicidality. However, all previous empirical work has been cross‐sectional. We provide the first longitudinal test of the theoretical predictions, in a sample of 79 students who reported suicidality. Participants completed self‐report measures of suicidal ideation, depression, defeat, and entrapment at two time points, approximately 12 months apart. People higher in defeat became more suicidal over time (β = .45), with baseline levels of suicidality and depressive symptoms controlled. The current results support the posited role of perceived defeat in driving suicidal ideation.
Fabrication of high-aspect-ratio lightpipes
Authors: Ye Winnie N. , Duane Peter , Wober Munib , Crozier Kenneth B.
Published: May 2011

The authors report the development of two fabrication processes for creating high-aspect-ratio lightpipes in a 10 μm thick SiO2 layer, with smooth, uniform, and straight vertical sidewalls. Both processes require only standard optical lithography, without the need for advanced electron beam or deep-UV lithography. One process employs a dielectric etch mask and the other uses a negative photoresist as the etch mask. The experiments show that the CF4-based reaction gases are best for deep etching with high selectivity and etch rate. Trenches with diameters or width of 1.5 μm are demonstrated, with an aspect ratio of 7.2:1 and a sidewall angle of 87.4°. The authors also achieve cylindrical lightpipes with an aspect ratio of 3.8:1 and a sidewall angle of 89.5°. They anticipate that these high-aspect-ratio lightpipe structures would be useful for complementary metal-oxide semiconductor image sensors, where they would increase the efficiency of light collection, and reduce interpixel cross-talk.
The apparent “super-Carnot” efficiency of hurricanes: Nature’s steam engine versus the steam locomotive
Authors: Denur Jack
Published: May 2011

The thermodynamics of the hurricane—Nature’s steam engine—presents surprising contrasts with that of the steam locomotive. The hurricane rejects not only its waste heat at the lowest available temperature (as all heat engines must do to maximize efficiency), but also its work (that is, the kinetic energy of its winds) via frictional dissipation at the highest available temperature. We show how the hurricane’s “super-Carnot” efficiency is consistent with the laws of thermodynamics. We also show that even standard heat engines can achieve “super-Carnot” efficiency, albeit via a different mechanism and to a far inferior degree than the hurricane.
Classical physics of thermal scalar radiation in two spacetime dimensions
Authors: Boyer Timothy H.
Published: May 2011

Thermal scalar radiation in two spacetime dimensions is treated within relativistic classical physics. We first consider an inertial frame in which we give the analogues of Boltzmann’s derivation of the Stefan–Boltzmann law and Wien’s derivation of the displacement theorem using the scaling appropriate to relativistic radiation theory. The spectrum of classical scalar zero-point radiation in an inertial frame is derived both from scale invariance and from Lorentz invariance. We then consider the behavior of thermal radiation in a coordinate frame undergoing (relativistic) constant acceleration. The classical zero-point radiation of inertial frames is transformed to the coordinates of an accelerating frame. Although the two-field correlation function for zero-point radiation at different spatial points at a single time is the same for inertial and accelerating frames, the correlation function at two different times at a single spatial coordinate is different and, in an accelerating frame, has a natural extension to nonzero temperature. The thermal spectrum in the accelerating frame is then transferred back to an inertial frame, giving the familiar Planck result.
What is the boundary condition for the radial wave function of the Schrödinger equation?
Authors: Khelashvili Anzor A. , Nadareishvili Teimuraz P.
Published: May 2011

There is much discussion in the mathematical physics literature as well as in quantum mechanics textbooks on spherically symmetric potentials. Nevertheless, there is no consensus about the behavior of the radial function at the origin, particularly for singular potentials. A careful derivation of the radial Schrödinger equation leads to the appearance of a delta function term when the Laplace operator is written in spherical coordinates. As a result, regardless of the behavior of the potential, an additional constraint is imposed on the radial wave function in the form of a vanishing boundary condition at the origin.
How Einstein confirmed E0=mc2
Authors: Hecht Eugene
Published: May 2011

The equivalence of mass m and rest-energy E0 is one of the great discoveries of all time. Despite the current wisdom, Einstein did not derive this relation from first principles. Having conceived the idea in the summer of 1905 he spent more than 40 years trying to prove it. We briefly examine all of Einstein’s conceptual demonstrations of E0=mc2, focusing on their limitations and his awareness of their shortcomings. Although he repeatedly confirmed the efficacy of E0=mc2, he never constructed a general proof. Leaving aside that it continues to be affirmed experimentally, a rigorous proof of the mass-energy equivalence is probably beyond the purview of the special theory.
Decay of wave packet revivals in the asymmetric infinite square well
Authors: Timberlake Todd K. , Camp Seth
Published: May 2011

In the infinite square well, any wave function will return to its initial state at integer multiples of the revival time. Most quantum systems do not exhibit perfect revivals, but some exhibit partial revivals in which the wave function returns close to its initial state. Subsequent partial revivals usually deteriorate in quality. We discuss the reasons for the perfect revivals in the infinite square well and how a small change in the potential disrupts the revivals. As an example, we examine partial revivals of a Gaussian wave packet in an infinite square well with a step. First-order and second-order perturbation theory show that the rate at which revivals decay depends on the location of the step.
Millimeter-wave Bragg diffraction of microfabricated crystal structures
Authors: Yuan C. P. , Lin S. Y. , Chang T. H. , Shew B. Y.
Published: May 2011

A compact diffraction apparatus is developed with millimeter-wave propagation between two parallel plates. Two types of microfabricated model crystals are individually mounted on a rotatable structure. In contrast to previous work, the experimental results agree well with Bragg’s predictions because multiple scattering is minimized in this configuration. Factors that affect the resolution and signal strength, such as the number of scatterers, cylinder radius, and the distance between the detector and the model crystal, are analyzed. The apparatus offers a visually accessible way to teach students about crystal structure as well as scattering and diffraction.
Resource Letter PS-2: Physics of Sports
Authors: Frohlich Cliff
Published: May 2011

This Resource Letter provides a guide to the literature on the physics of sports, updating Resource Letter PS-1, published 25 years ago (Ref. 17). The intent is to suggest literature for anyone curious about the basic physics of particular sports, for physics teachers searching for sports examples to augment their teaching, and for physicists contemplating research on unsolved sports-related questions.
Comment on “A close examination of the motion of an adiabatic piston,” by Eric A. Gislason [Am. J. Phys. 78 (10), 995–1001 (2010)]
Authors: de Abreu Rodrigo , Guerra Vasco
Published: May 2011

A recent paper by Gislason treats the adiabatic piston, a system of two ideal gases in a horizontal cylinder and separated by an insulating piston that moves without friction. The analysis in this paper is comprehensive and useful as a teaching tool, but is somewhat misleading if not understood in the appropriate context. The evolution to equilibrium involves two mechanisms, a faster one leading to the equalization of pressures, and a slower one bringing the system to identical temperatures. Gislason addressed only the first mechanism. We note that the eventual final state is described by thermodynamics. Therefore, a discussion of the adiabatic piston can be enriched to promote a proper and general view of thermodynamics.
Duality of force laws and conformal transformations
Authors: Kothawala Dawood
Published: May 2011

As was first noted by Isaac Newton, the two most famous ellipses of classical mechanics, arising from the force laws F∝r and F∝1/r2, can be mapped onto each other by changing the location of the center of force. Less well known is that this mapping can also be achieved by the complex transformation, z→z2. We derive this result and its generalization by writing the Gaussian curvature in its covariant form, and then changing the metric by a conformal transformation which mimics this mapping of the curves. We indicate how the conserved Laplace–Runge–Lenz vector for the 1/r2 force law transforms under this transformation, and compare it with the corresponding quantities for the linear force law. Our main aim is to present this duality by introducing concepts from differential geometry.
Exact non-Hookean scaling of cylindrically bent elastic sheets and the large-amplitude pendulum
Authors: Kashcheyevs Vyacheslavas
Published: May 2011

A sheet of elastic foil rolled into a cylinder and deformed between two parallel plates acts as a non-Hookean spring if deformed normally to the axis. For large deformations the elastic force shows an interesting inverse square dependence on the interplate distance. This phenomenon was used as the basis for an experimental problem at the 41st International Physics Olympiad. We show that the corresponding variational problem for the equilibrium energy of the deformed cylinder is equivalent to a minimum action description of a simple gravitational pendulum with an amplitude of 90°. We use this analogy to show that the power-law of the force is exact for distances less than a critical value. An analytical solution for the elastic force is found and confirmed by measurements over a range of deformations covering both linear and nonlinear behaviors.
Refraction in spacetime
Authors: Jääskeläinen Markku , Lombard Marijke , Zülicke Ulrich
Published: May 2011

Refraction, interference, and diffraction are distinguishing features of wavelike phenomena. Although they are usually associated only with a purely spatial wave-propagation pattern, analogs to interference and diffraction involving the spatio-temporal dynamics of waves in one dimension have been discussed. We complete the triplet of analogies by discussing how spatio-temporal analogs to refraction are exhibited by a quantum particle in one dimension that is scattering off a step barrier. Similarly, birefringence in spacetime occurs for a spin-1/2 particle in a magnetic field.