bluuebunny/crossref_metadata_2025 huggingface dataset:
Policy Analysts in the Bureaucracy Revisited: The Nature of Professional Policy Work in Contemporary Government
Authors: HOWLETT MICHAEL , WELLSTEAD ADAM M.
Published: July 2011

Thirty‐five years ago Arnold Meltsner observed that professional policy analysts in the U.S. government undertook several roles in the policy‐making process, the most common of which involved “technical” information processing while others were more “political” in nature. Although still prescient, more recent empirical studies of professional policy work have found little evidence of the predominance of technicians in the ranks of analysts employed in public policy bureaucracies. However, only very weak and partial information exists on the situation in most countries, and descriptions of the nature of policy work often remain primarily normative and lacking in empirical referents. This article reexamines the duties and nature of contemporary professional policy analysis in the Canadian bureaucracy. It reveals that contemporary policy work is constituted by more complex and multisided practices than Meltsner and his followers described. These findings are significant for those wishing to understand, and improve, the nature of policy work in contemporary government.

Hace treinta y cinco años Arnold Meltsner observó que los analistas legislativos profesionales en el gobierno de los Estados Unidos se encargan de diferentes tareas en el proceso legislativo, el más común involucraba el proceso de información “técnica” mientras que otros eran de una naturaleza más “política”. Estudios empíricos más recientes del trabajo profesional legislativo han encontrado poca evidencia del predominio de técnicos en puestos analíticos en las burocracias del sector público. Sin embargo, existe tenue y parcial información sobre la situación de la mayoría de los países y la descripción de la naturaleza del trabajo legislativo permanece normativa y carente de referentes empíricos. Este estudio reexamina los deberes y naturaleza de analistas legislativos profesionales en la burocracia Canadiense y revela que el trabajo legislativo contemporáneo está constituido por prácticas más complejas de las que Meltsner y sus partidarios describieron. Estos hallazgos son significativos para aquellos que deseen comprender y mejorar la naturaleza del trabajo legislativo en la gobernabilidad contemporánea.
Human Glioblastoma Stem‐Like Cells are More Sensitive to Allogeneic NK and T Cell‐Mediated Killing Compared with Serum‐Cultured Glioblastoma Cells
Authors: Avril Tony , Vauleon Elodie , Hamlat Abderrahmane , Saikali Stéphan , Etcheverry Amandine , Delmas Caroline , Diabira Sylma , Mosser Jean , Quillien Véronique
Published: July 2011

Glioblastoma multiforme (GBM) is the most dramatic primary brain cancer with a very poor prognosis because of inevitable disease recurrence. The median overall survival is less than 1 year after diagnosis. Cancer stem cells have recently been disclosed in GBM. GBM stem‐like cells (GSCs) exhibit resistance to radio/chemotherapeutic treatments and are therefore considered to play an important role in disease recurrence. GSCs are thus appealing targets for new treatments for GBM patients. In this study, we show that GBM cells with stem cell characteristics are resistant to lysis mediated by resting natural killer (NK) cells because of the expression of MHC class I molecules. However, GSCs are killed by lectin‐activated NK cells. Furthermore, in experiments using the therapeutic antibody CetuximAb, we show that GSCs are sensitive to antibody‐mediated cytotoxicity. We confirm the sensitivity of GSC to cytotoxicity carried out by IL2‐activated NK cells and tumor‐specific T cells. More importantly, we show that GSCs are more sensitive to NK and T cell‐mediated lysis relatively to their corresponding serum‐cultured GBM cells obtained from the same initial tumor specimen. Altogether, these results demonstrate the sensitivity of GSC to immune cell cytotoxicity and, therefore, strongly suggest that GSCs are suitable target cells for immunotherapy of GBM patients.
Expansive open‐door laminoplasty and selective anterior cervical decompression and fusion for treatment of multilevel cervical spondylotic myelopathy
Authors: Liu Xin‐yu , Yuan Suo‐mao , Tian Yong‐hao , Zheng Yan‐ping , Li Jian‐min
Published: July 2011

Objective:  To evaluate the clinical results of combined expansive open‐door laminoplasty by splitting of spinous processes and selective anterior cervical decompression and fusion in treatment of multilevel severe cervical spondylotic myelopathy (CSM).

Methods:  Twenty‐eight patients (16 men and 12 women) underwent one‐stage combined expansive open‐door laminoplasty and selective anterior decompression and fusion for severe CSM; the average patient age was 51.3 years (range, 32–63 years). Clinical results were assessed by Japanese Orthopaedic Association (JOA) scores, number of finger grip and releases (G and R) in ten seconds, hand‐grip strength, visual analog scale (VAS) of axial pain, and C2‐C7 angle.

Results:  There was no worsening of neurological symptoms due to cord injury, cerebrospinal fluid leakage, or wound infection. All cases completed one‐year follow‐up. The JOA scores, number of G and R in ten seconds, and hand‐grip strength were all significantly improved (P < 0.05). Satisfactory decompression was shown by MRI or CT to have been achieved in all cases. The C2‐C7 angle did not differ significantly from that found pre‐operatively. The axial neck pain score was 2.0 ± 0.1 on VAS.

Conclusion:  Combined expansive open‐door laminoplasty by splitting of spinous processes and selective anterior decompression and fusion achieves complete spinal canal decompression with minimal morbidity; this strategy is effective in improving the surgical outcomes of CSM in one‐year follow‐up.
Serum biochemical reference intervals for wild dwarf ornate wobbegong sharks (Orectolobus ornatus)
Authors: Otway Nicholas M. , Ellis Megan T. , Starr Rod
Published: July 2011

Background: Sharks are important to sport and commercial fishing, public aquaria, and research institutions. However, serum biochemical reference values have been established for few species.

Objective: The aim of this study was to establish serum biochemical reference intervals for wild‐caught dwarf ornate wobbegong sharks (Orectolobus ornatus).

Methods: Fifty wobbegongs were caught, and their health status, sex, length, and weight were evaluated and recorded. Following collection of blood, serum biochemical analytes were measured and analyzed using standard analytical and statistical methods. Combined samples generated means, medians, and reference intervals.

Results: For the measured analytes, means (reference intervals) were as follows: sodium 287 (284–289) mmol/L, chloride 277 (274–280) mmol/L, potassium 5.2 (5.0–5.3) mmol/L, total calcium 4.6 (4.5–4.7) mmol/L, magnesium 1.9 (1.7–2.0) mmol/L, inorganic phosphate 1.8 (1.7–1.9) mmol/L, glucose 2.6 (2.4–2.8) mmol/L, total protein 46 (45–47) g/L, urea 396 (392–401) mmol/L, creatinine ≤0.02 mmol/L, total bilirubin 2.0 (1.9–2.1) μmol/L, cholesterol 1.3 (1.2–1.4) mmol/L, triglyceride 0.5 (0.4–0.6) mmol/L, alkaline phosphatase 24 (21–28) U/L, alanine aminotransferase 3 U/L, aspartate aminotransferase 28 (25–31) U/L, creatine kinase 49 (38–59) U/L, and osmolarity 1104 (1094–1114) mmol/L. Serum values were not affected by sex, length, or weight.

Conclusions: Established reference values will assist with clinical evaluation and treatment of dwarf ornate wobbegongs in aquaria, research institutions, and the wild.
Erbium‐Doped Fluoroborate Glasses for Near Infrared Broadband Amplifiers
Authors: Saleem Shaik Abdul , Jamalaiah Bungala Chinna , Sasikala Thammisetty , Mohan Babu Asanapuram , Jayasimhadri Mula , Rama Moorthy Lalapet
Published: July 2011

Erbium (Er3+)‐doped alkali lead tellurofluoroborate (RLTB) glasses were prepared and characterized systematically through optical absorption and emission measurements. The emission spectra in the range 450–900 and 1400–1800 nm were recorded by exciting the samples with 532 nm (Nd : YVO4 crystal) and 514.5 nm (Ar+ laser), respectively. Applying Judd–Ofelt analysis, the intensity parameters have been determined using experimental oscillator strengths of absorption bands. From the Judd–Ofelt intensity parameters, some important fluorescence properties such as spontaneous transition probabilities, radiative lifetimes and luminescence branching ratios for the 4S3/2→4I15/2 (0.55 μm), 4S3/2→4I13/2 (0.85 μm), and 4I13/2→4I15/2 (1.54 μm) emission transitions of Er3+ ion in RLTB glasses have been calculated. The continuous pumping of the samples results in fast nonradiative decay through 2H11/2→4F9/2 (~3500 cm−1) transition, which in turn causes the population of Er3+ ions from 2H11/2 state to the higher 4F3/2 state. The emission cross sections determined for the 4I13/2→4I15/2 (1.54 μm) transition using the McCumber theory are in good agreement with the values obtained from the Judd–Ofelt analysis. From evaluated radiative parameters, it is suggested that these RLTB glasses are more suitable candidates for 0.85 and 1.54 μm broadband optical amplifiers.
Nephrosplenic entrapment of the large colon in 142 horses (2000–2009): Analysis of factors associated with decision of treatment and short‐term survival
Authors: LINDEGAARD C. , EKSTRØM C. T. , WULF S. B. , VENDELBO J. M. B. , ANDERSEN P. H.
Published: July 2011

Reasons for performing study:Previous studies indicate similar overall survival of horses with nephrosplenic entrapment of the large colon (NSE), regardless of treatment strategy. Short‐term survival of a primarily conservative treatment strategy without rolling under general anaesthesia (GA) and a low proportion of surgical intervention as well as indicators of short‐term nonsurvival has not been documented.

Objectives:To document short‐term survival of horses with NSE treated in a university referral hospital with a low rate of surgical interventions and to determine factors associated with the decision of treatment and short‐term nonsurvival.

Methods:A retrospective review of medical records of 142 horses diagnosed with NSE between January 2000 and October 2009 was undertaken. Case details and clinical parameters from the initial examination, treatment and outcome were recorded. Factors associated with decision of treatment and short‐term survival were identified by multiple logistic regression analysis.

Results:Warmblood breeds were over‐represented in comparison to the general colic population. Overall short‐term survival was 91.5% (130/142) which is similar to previous studies. Three horses considered to be in need of surgery were subjected to euthanasia for economical reasons before treatment. Of 114 conservatively treated horses, 110 (96.5%) survived, as did 20/25 (80%) of surgically treated horses. Nine conservatively managed horses were treated with phenylephrine. Gastric reflux (P = 0.0077), pain (P = 0.024) and abdominal distension (P = 0.05) were associated with the decision to treat surgically. Increased heart rate (P<0.001), and surgery (P = 0.032) were associated with reduced likelihood of short‐term survival.

Conclusions and potential relevance:Overall short‐term survival was similar to that reported in previous studies with higher proportions of surgically managed cases. Consequently, horses with NSE should be managed by a primarily conservative treatment strategy, with the decision to treat surgically based on specific evidence based criteria.
Multiple small intestinal pseudodiverticula associated with lymphoma in three horses
Authors: MAIR T. S. , PEARSON G. R. , SCASE T. J.
Published: July 2011

Three mature horses presented with progressive weight loss, inappetence, ventral abdominal oedema and lethargy. Two of the animals had intermittent signs of low grade abdominal pain. At presentation, all 3 had hypoalbuminaemia; 2 had hyperfibrinogenaemia and the other had neutrophilia. An oral glucose tolerance test was performed in 2 cases, both of which demonstrated impaired glucose absorption. One pony treated with corticosteroids failed to improve and developed peritonitis and was subjected to euthanasia after 2 weeks. One pony had small intestinal biopsies obtained via a standing flank laparotomy, which revealed a mainly mononuclear cell infiltrate of the mucosa. It failed to respond to treatment with antibiotics and corticosteroids and, after 2 months, developed sternal oedema in addition to the ventral abdominal oedema and peritonitis and was subjected to euthanasia. The remaining pony deteriorated despite symptomatic therapy and was subjected to euthanasia after one week. Atpost mortemexamination, all 3 animals had multifocal lesions of small intestinal wall thickening, mucosal ulceration, pseudodiverticula and enlarged mesenteric lymph nodes. One pony also had a multinodular mass at the root of the mesentery, a mediastinal mass and a lung mass. Histological examination confirmed the presence of lymphoma of the intestinal wall atpost mortemexamination in each case and immunohistochemistry (including retrospective evaluation of the intestinal biopsies obtained from the pony that underwent a flank laparotomy) indicated that the lymphomas were of T cell origin.
Recurrent colic in the horse: Incidence and risk factors for recurrence in the general practice population
Authors: SCANTLEBURY C. E. , ARCHER D. C. , PROUDMAN C. J. , PINCHBECK G. L.
Published: July 2011

Reasons for performing study:The frequency of recurrent colic in the UK equine general practice population is previously unreported. Elucidating risk factors for recurrent colic could provide a basis for clinical decision making and interventions.

Objectives:To determine the incidence rate of and risk factors for recurrent colic.

Hypotheses:Horse management, prophylactic health care and innate behaviour contribute to the risk of recurrent colic.

Methods:A cohort of 127 horses was enrolled at the point of a veterinary‐diagnosed medical colic episode. Participating owners completed a baseline and 3 follow‐up telephone questionnaires over one year. Clinical details of each colic episode were collected with data on management, behaviour and preventive healthcare. Incidence was calculated using time at risk data; non‐time varying covariates were assessed for association with recurrent colic using multivariable logistic regression.

Results:The recurrence rate was 50 colic events/100 horse years at risk (HYAR). Including only veterinary attended recurrent colic episodes the incidence was 35 colic events per 100 HYAR. A multivariable logistic regression model was built to explore non‐time varying risk factors for recurrence collected from baseline data. The model showed that horses that have a known dental problem (OR 5.5, 95% CI 1.3, 23.1) or crib‐bite/windsuck (OR 12.1, 95% CI 1.4, 108.1) were at increased risk of recurrence during the year following a colic event.

Conclusions and potential relevance:The incidence of recurrence in horses following a medical episode of colic is high in this population and represents a welfare concern. The incidence rate can be used to compare intervention efficacy in similar populations. Identified risk factors could provide the basis for management interventions or highlight at risk individuals.
An update on cyathostomins: Anthelmintic resistance and diagnostic tools
Authors: STRATFORD C. H. , McGORUM B. C. , PICKLES K. J. , MATTHEWS J. B.
Published: July 2011

Cyathostomins represent a potential cause of equine morbidity and have become the main focus of endoparasite control in managed horses. All grazing horses are at risk of infection with cyathostomins; therefore, the application of appropriate management measures is essential. Anthelmintics currently comprise the main method of control for equine nematodes and the ready availability of these products in some countries has resulted in their use becoming dissociated from veterinary involvement. This is concerning given the levels of anthelmintic resistance that have been recorded in cyathostomin populations. It is important that veterinarians re‐establish control over the implementation of parasite control programmes, a major objective of which should be the preservation of anthelmintic efficacy. This article details the principles of cyathostomin control in horses with particular reference to anthelmintic resistance, and the use and interpretation of diagnostic tests for detecting cyathostomins and identifying anthelmintic resistance.
Cardiovascular effects of N‐butylscopolammonium bromide and xylazine in horses
Authors: MORTON A. J. , VARNEY C. R. , EKIRI A. B. , GROSCHE A.
Published: July 2011

Reasons for performing study:N‐butylscopolammonium bromide (NBB) and xylazine are commonly used medications for the treatment of spasmodic colic and other forms of abdominal pain in horses. Both NBB and xylazine exert significant effects on the cardiovascular system and other vital systems of horses.

Objective:To evaluate the effects of i.v. administration of NBB, xylazine, and the combination of NBB and xylazine on heart rate, other commonly measured physiological parameters, cardiac rhythm and blood pressure.

Methods:Six mature horses of mixed breed were used. In a random cross‐over design, each horse was given 0.3 mg/kg bwt of NBB i.v., 0.25 mg/kg bwt xylazine i.v., and a combination of 0.3 mg/kg bwt NBB and 0.25 mg/kg bwt xylazine. Heart rate, physiological parameters, cardiac rhythm and indirect blood pressure were recorded at timed intervals before and 60 min following administration.

Results:Heart rate and blood pressure were significantly elevated immediately following administration of NBB or NBB with xylazine. Administration of NBB with xylazine resulted in significantly greater initial and peak blood pressure values than with NBB alone. Administration of xylazine resulted in a decrease in heart rate, with an initial increase in blood pressure followed by a decrease in blood pressure. Sinus tachycardia was seen with NBB, and NBB and xylazine administration. First and second degree atrioventricular block was identified with xylazine administration. Ventricular tachycardia was identified in one horse following NBB and xylazine administration.

Conclusions:Results of this study suggest that the effects of administration of NBB alone or in combination with xylazine to horses with colic, especially to those with systemic cardiovascular compromise, should be considered carefully to assess condition and predict prognosis accurately, and to avoid potential adverse effects.
Ultrastructural changes in the equine colonic mucosa after ischaemia and reperfusion
Authors: GROSCHE A. , MORTON A. J. , GRAHAM A. S. , SANCHEZ L. C. , BLIKSLAGER A. T. , POLYAK M. M. R. , FREEMAN D. E.
Published: July 2011

Reason for performing study:Ultrastructural changes in the epithelium can provide information on early changes in barrier properties, repair and inflammation in equine colon after ischaemia and reperfusion (I/R).

Objectives:To describe the morphology and ultrastructure of the epithelium in equine large colonic mucosa after I/R, and the response of inflammatory cells to injury.

Methods:Ischaemia was induced for 1 h followed by 4 h of reperfusion in a 40 cm segment of the pelvic flexure in 6 horses. Mucosal biopsies before and after ischaemia, and after 1, 2 and 4 h of reperfusion were fixed in glutaraldehyde/paraformaldehyde and osmium tetroxide, and embedded in epon. Morphological and ultrastructural changes were evaluated in toluidine blue‐stained semithin sections by light microscopy and in thin sections stained with uranyl acetate/lead citrate by transmission electron microscopy.

Results:Ischaemia caused swelling of epithelial cells and their organelles, opening of tight junctions, detachment from the basement membrane, early apoptosis and single cell necrosis. Autophagy was a prominent feature in epithelial cells after ischaemia. Reperfusion was characterised by apoptosis, epithelial regeneration and restoration of apical cell junctions. Phagocytic‐like vacuoles containing cellular debris and bacteria were evident in epithelial cells after reperfusion. Paracellular and subepithelial clefts formed, accompanied by infiltration of neutrophils, lymphocytes and eosinophils into the epithelium. Subepithelial macrophages and luminal neutrophils had increased phagocytic activity.

Conclusions:Ischaemia caused ultrastructural damage to the colonic epithelium, but epithelial cells recovered during reperfusion.

Potential relevance:Transmission electron microscopy can demonstrate subtle ultrastructural damage to epithelial cells and evidence of recovery after I/R in equine colon.
Ex vivo comparison of three hand sewn end‐to‐end anastomoses in normal equine jejunum
Authors: SHERLOCK C. , LEE W. , MUELLER P. O. E. , EGGLESTON R. , EPSTEIN K.
Published: July 2011

Reasons for performing study: Although single layer techniques are preferred in man and small animals for small intestinal end‐to‐end anastomoses, double layer techniques are more popular in equine surgery. This study was undertaken to evaluate the ex vivo characteristics of 2 single layer anastomoses in comparison to the traditionally performed double layer anastomosis in equine jejunum.

Objectives: To compare ex vivo: 1) construction time; 2) bursting pressure; and 3) lumen size reduction of 3 suture patterns (double layer simple continuous/Cushing pattern [2C]; single layer Lembert pattern [1L]; and single layer Cushing pattern [1C]) for end‐to‐end equine jejunojejunostomies.

Methods: End‐to‐end jejunojejunostomies were constructed using 2C (n = 7), 1L (n = 7) and 1C (n = 7) in harvested equine jejunum and construction times were recorded. Anastomosed and control segments were distended with gas until failure. Intraluminal pressure at failure and mode of failure were recorded. Lumen size reduction was calculated as a percentage decrease from control jejunum. Results were compared using an ANOVA and P<0.05 was considered significant.

Results: The 1C anastomoses were faster to construct than the 1L anastomoses, which were faster to construct than the 2C anastomoses. There were no differences in bursting pressures between the different anastomoses and control jejunum. All anastomoses decreased lumen size from control values but there were no differences in lumen reduction between types of anastomoses.

Conclusions: Single layer anastomoses are faster to construct than double layer anastomoses, with the 1C being fastest. Single layer anastomoses are as strong and result in comparable lumen size reduction as traditional 2C anastomoses.

Potential relevance: As the 1C anastomosis results in less exposed potentially adhesiogenic suture material than the 1L while providing adequate strength and similar luminal size reduction, the 1C may be better for equine small intestine anastomosis and further in vivo studies are warranted.
Discursive social psychology now
Authors: Parker Ian
Published: July 2011

This paper reviews the progress of discourse‐analytic approaches in social psychology from the late 1980s to the present day, with a particular focus on the way conceptual and methodological contributions from within the Discourse and Rhetoric Group at Loughborough University have negotiated a positive role for innovative studies of language in the discipline of psychology. Social psychology has become a key site for the accumulation of a series of empirical studies that have seen the flourishing of a distinctive form of ‘discursive social psychology’ that has succeeded in moving from the margins of the discipline to a more accepted position. The paper traces this trajectory of discourse analysis from the limits to the centre of social psychology attending to five features that now characterise its contribution to psychology; an emphasis on everyday conversation, a concern with interpersonal interaction, explication of formal sequences; an insistence on empirical claims; and fidelity to the ethos of its host discipline. The paper concludes with some comments on the wider context of this new approach inside psychology today.
On New Aspects of Nested Carbon Nanotubes as Gigahertz Oscillators
Authors: Ansari R. , Motevalli B.
Published: July 2011

Nested carbon nanotubes exhibit telescopic oscillatory motion with frequencies in the gigahertz range. In this paper, our previously proposed semi-analytical expression for the interaction force between two concentric carbon nanotubes is used to solve the equation of motion. That expression also enables a new semi-analytical expression for the precise evaluation of oscillation frequency to be introduced. Alternatively, an algebraic frequency formula derived based on the simplifying assumption of constant van der Waals force is also given. Based on the given formulas, a thorough study on different aspects of operating frequencies under various system parameters is conducted, which permits fresh insight into the problem. Some notable improvements over the previously drawn conclusions are made. The strong dependence of oscillatory frequency on system parameters including the extrusion distance and initial velocity of the core as initial conditions for the motion is shown. Interestingly, our results indicate that there is a special initial velocity at which oscillatory frequency is unique for any arbitrary length of the core. A particular relationship between the escape velocity (the minimum initial velocity beyond which the core will leave the outer nanotube) and this specific initial velocity is also revealed.
Stem Cell Proliferation in the Skin: α-Catenin Takes Over the Hippo Pathway
Authors: Flores Elsa R. , Halder Georg
Published: July 2011

α-Catenin inhibits the transcriptional coactivator Yap to limit epidermal stem cell proliferation.
Pharmacokinetics of Ethionamide in Children
Authors: Thee S. , Seifart H. I. , Rosenkranz B. , Hesseling A. C. , Magdorf K. , Donald P. R. , Schaaf H. S.
Published: July 2011

Ethionamide (ETH), a second-line antituberculosis drug, is frequently used in treating childhood tuberculosis. Data supporting ETH dose recommendations in children are limited. The aim of this study was to determine the pharmacokinetic parameters for ETH in children on antituberculosis treatment including ETH. ETH serum levels were prospectively assessed in 31 children in 3 age groups (0 to 2 years, 2 to 6 years, and 6 to 12 years). Within each age group, half received rifampin (RMP). Following an oral dose of ETH (15 to 20 mg/kg of body weight), blood samples were collected at 0, 1, 2, 3, 4, and 6 h following 1 and 4 months of ETH therapy. The maximum serum concentration (
C
max
), time to
C
max
(
T
max
), and area under the time-concentration curve from 0 to 6 h (AUC
0–6
) were calculated. Younger children were exposed to lower ETH concentrations than older children at the same mg/kg body weight dose. Age correlated significantly with the AUC after both 1 month (
r
= 0.50,
P
= 0.001) and 4 months (
r
= 0.63,
P
= 0.001) of therapy. There was no difference in the AUC or
C
max
between children receiving concomitant treatment with RMP and those who did not. Time on treatment did not influence the pharmacokinetic parameters of ETH following 1 and 4 months of therapy. HIV infection was associated with lower ETH exposure. In conclusion, ETH at an oral dose of 15 to 20 mg/kg results in sufficient serum concentrations compared to current adult recommended levels in the majority of children across all age groups. ETH levels were influenced by young age and HIV status but were not affected by concomitant RMP treatment and duration of therapy.
Outcomes of Moderate-to-Severe Pneumocystis Pneumonia Treated with Adjunctive Steroid in Non-HIV-Infected Patients
Authors: Moon Song Mi , Kim Tark , Sung Heungsup , Kim Mi-Na , Kim Sung-Han , Choi Sang-Ho , Jeong Jin-Yong , Woo Jun Hee , Kim Yang Soo , Lee Sang-Oh
Published: July 2011

While it is well-known that adjunctive corticosteroid use improves the outcome of moderate-to-severePneumocystis jiroveciipneumonia (PcP) in patients with human immunodeficiency virus (HIV), there are limited data on its efficacy in non-HIV-infected patients with PcP. Patients undergoing fiber-optic bronchoscopy with bronchoalveolar lavage for suspected PcP from January 2007 through December 2010 were reviewed retrospectively. We compared demographics, clinical characteristics, and outcomes in 88 non-HIV-infected patients with moderate-to-severe PcP with (n= 59) and without (n= 29) adjunctive corticosteroid use. Outcomes of PcP were assessed by respiratory failure and 30-day and 90-day all-cause mortality. Survival curves were analyzed by the Kaplan-Meier method and estimated by the log rank test. All-cause mortality of moderate-to-severe PcP at 90 days was lower in the solid-organ transplant recipients than in all other patients (6/26 [23%] versus 34/62 [55%], respectively;P= 0.006), and mortality at 30 days was lower in patients with hematologic malignancies than in all other patients (4/26 [15%] versus 24/62 [39%], respectively;P= 0.03). The outcomes of PcP were not significantly different in moderate-to-severe PcP patients with and without adjunctive corticosteroid use, regardless of recent corticosteroid use. Survival analysis of PcP patients with and without corticosteroid use by the Kaplan-Meier method also did not reveal any difference (log rank test;P= 0.81). There again was no difference within the subgroup of PcP patients with solid-organ transplants. Adjunctive corticosteroid use may not improve the outcome of moderate-to-severe PcP in non-HIV-infected patients.
Extended-Spectrum AmpC Cephalosporinase in Acinetobacter baumannii: ADC-56 Confers Resistance to Cefepime
Authors: Tian Guo-Bao , Adams-Haduch Jennifer M. , Taracila Magdalena , Bonomo Robert A. , Wang Hong-Ning , Doi Yohei
Published: July 2011

ADC-56, a novel extended-spectrum AmpC (ESAC) β-lactamase, was identified in an
Acinetobacter baumannii
clinical isolate. ADC-56 possessed an R148Q change compared with its putative progenitor, ADC-30, which enabled it to hydrolyze cefepime. Molecular modeling suggested that R148 interacted with Q267, E272, and I291 through a hydrogen bond network which constrained the H-10 helix. This permitted cefepime to undergo conformational changes in the active site, with the carboxyl interacting with R340, likely allowing for better binding and turnover.
The Stringent Response Is Essential for Pseudomonas aeruginosa Virulence in the Rat Lung Agar Bead and Drosophila melanogaster Feeding Models of Infection
Authors: Vogt Stefanie L. , Green Christopher , Stevens Katarzyna M. , Day Brad , Erickson David L. , Woods Donald E. , Storey Douglas G.
Published: July 2011

The stringent response is a regulatory system that allows bacteria to sense and adapt to nutrient-poor environments. The central mediator of the stringent response is the molecule guanosine 3′,5′-bispyrophosphate (ppGpp), which is synthesized by the enzymes RelA and SpoT and which is also degraded by SpoT. Our laboratory previously demonstrated that a
relA
mutant of
Pseudomonas aeruginosa
, the principal cause of lung infections in cystic fibrosis patients, was attenuated in virulence in a
Drosophila melanogaster
feeding model of infection. In this study, we examined the role of
spoT
in
P. aeruginosa
virulence. We generated an insertion mutation in
spoT
within the previously constructed
relA
mutant, thereby producing a ppGpp-devoid strain. The
relA spoT
double mutant was unable to establish a chronic infection in
D. melanogaster
and was also avirulent in the rat lung agar bead model of infection, a model in which the
relA
mutant is fully virulent. Synthesis of the virulence determinants pyocyanin, elastase, protease, and siderophores was impaired in the
relA spoT
double mutant. This mutant was also defective in swarming and twitching, but not in swimming motility. The
relA spoT
mutant and, to a lesser extent, the
relA
mutant were less able to withstand stresses such as heat shock and oxidative stress than the wild-type strain PAO1, which may partially account for the inability of the
relA spoT
mutant to successfully colonize the rat lung. Our results indicate that the stringent response, and SpoT in particular, is a crucial regulator of virulence processes in
P. aeruginosa
.
Patient safety incidents associated with obesity: a review of reports to the National Patient Safety Agency and recommendations for hospital practice
Authors: Booth C M A , Moore C E , Eddleston J , Sharman M , Atkinson D , Moore J A
Published: July 2011

Background

The incidence and prevalence of obesity are increasing world wide. In the UK, obesity governmental strategy has primarily focused on prevention measures, with less focus on the demands of treating obese patients in hospital. Increasing service demand by obese patients coupled with a lack of adequate provision for care of these patients may lead to an increase in patient safety incidents. By classifying patient safety incidents associated with obesity reported to the National Patient Safety Agency, this report aims to identify areas for improvement in the quality and safety of care of the obese patient

Methods

A search of the National Reporting and Learning System database was conducted for all incidents caused by or relating to obesity for the period 1 January 2005 to 31 August 2008. The keywords ‘obesity’, ‘overweight’, ‘BMI’ (body mass index), and ‘bariatric’ were used. The relevant free text fields of the resulting set of incidents were then searched for the terms designed to isolate incidents occurring in anaesthesia, critical care, and surgery. Reported incidents were analysed and subsequently categorised to identify incident themes. Levels of harm were also established.

Results

555 patient safety incidents were identified; 388 met inclusion criteria for analysis. 148 incidents were related to assessment, diagnosis or treatment, 213 related to infrastructure and 27 related to staffing. The majority of incidents were classified as no or low harm. Three deaths were reported, all within the domain of anaesthesia.

Conclusions

This report identifies that the majority of safety incidents associated with obesity were related to infrastructure, suggesting that there is inadequate provision in place for the care of obese patients. While levels of harm were mostly low, the occurrence of incidents resulting in severe harm or death highlights the specific dangers associated with the care of the obese patient. A global approach to improving the safety of care delivery for obese patients is recommended, including obesity specific training, management structures, care pathways, and equipment provisioning.Further planning and development of operation policies is needed to ensure the safe delivery of healthcare to obese patients in the future.
Influence of fabric variables on clay–water–air capillary meniscus
Authors: Amarasinghe Priyanthi M. , Anandarajah A.
Published: July 2011

The mechanical behavior of unsaturated clays is strongly governed by capillary water and the resulting capillary forces. In this paper, the influence of fabric variables on the air–water capillary meniscus between clay particles is studied using molecular dynamics. Considering a system of two clay particles, the fabric variables studied are the angle between particles, edge-to-face separation, clay–water contact length, and particle thickness. The molecular dynamic results are analyzed to determine the contact angle and radius of curvature of the meniscus. It is found that the values of the contact angle fall within a narrow range for the fabric variables considered. The radius of curvature varies with the spacing and angle, but is derivable from knowledge of the contact angle.
One-dimensional consolidation behavior of cement-treated organic soil
Authors: Bobet Antonio , Hwang Joonho , Johnston Cliff T. , Santagata Marika
Published: July 2011

This paper addresses the effects of cement treatment on the one-dimensional (1D) consolidation behavior of a highly organic soil (LOI ∼ 40%–60%, where LOI is the loss on ignition), based on 1D constant rate of strain and incremental loading tests. The effects of Portland cement addition are evaluated for dosages ranging from 8% to 100% by dry mass of soil, corresponding to values of the cement factor of 24 and 296 kg of cement per cubic metre of untreated soil, within the range used in deep mixing practice. Additional parameters investigated are the impact of curing surcharge and duration. The most evident effect of the treatment is the development of a cementation-induced preconsolidation stress: the greater the cement dosage, the greater the preconsolidation stress and the greater the vertical effective stress that can be sustained at any void ratio. The results also provide a consistent picture of the effects of cement treatment on stiffness, hydraulic conductivity, coefficient of consolidation, and creep. Comparison to data obtained for the untreated soil demonstrates the “stable” nature of the structure generated as a result of treatment. The consolidation results are complemented by pH measurements, extraction tests, elemental analyses, and Fourier transform infra-red (FTIR) spectroscopy analyses, which provide insight into the interaction between soil organic matter and cement.
Links between biomass and tree demography in a northern hardwood forest: a decade of stability and change in Hubbard Brook Valley, New Hampshire
Authors: van Doorn Natalie S. , Battles John J. , Fahey Timothy J. , Siccama Thomas G. , Schwarz Paul A.
Published: July 2011

We resurveyed a network of sampling plots (n = 371) 10 years after its establishment in Hubbard Brook Experimental Forest (New Hampshire, USA) to quantify recent trends in tree biomass and demography. We found no significant change in live-tree biomass during the decade. Total biomass was 246 Mg·ha–1 (95%CI = 235–258) in 1995–1996 and 245 Mg·ha–1 (95%CI = 234–256) in 2005–2006. Annual mortality during the period for trees ≥ 10 cm diameter at breast height (1.37 m) averaged 9.7 trees·ha–1·year–1 (95% CI of annual mortality rate = 1.36%–1.84%·year–1). Tree recruitment into the census pool was 8.4 trees⋅ha–1·year–1 (95% CI = 5.8–10.6). Although overall forest biomass remained constant, there were marked shifts in the relative dominance of the canopy species. For example, the live biomass of Betula alleghaniensis Britton declined by 7%, whereas the live biomass of Picea rubens Sarg. increased by 6% and that of Acer saccharum Marshall increased by 4%. There was no instance of recruitment significantly exceeding mortality for the major species. Relative growth rates ranged from 1.03%·year–1 for Betula papyrifera Marshall to 1.99%·year–1 for Abies balsamea (L.) Mill. Our results confirmed earlier reports that the forest at Hubbard Brook is no longer aggrading. Current live-tree biomass is lower than expected. Although effects of novel disturbances documented on a regional level have not led to directional changes in tree demography at Hubbard Brook, we suggest that these novel stressors are depressing the biomass potential of the forest.
Effectiveness of forest management strategies to mitigate effects of global change in south-central Siberia
Authors: Gustafson Eric J. , Shvidenko Anatoly Z. , Scheller Robert M.
Published: July 2011

We investigated questions about the ability of broad silvicultural strategies to achieve multiple objectives (reduce disturbance losses, maintain the abundance of preferred species, mitigate fragmentation and loss of age-class diversity, and sequester aboveground carbon) under future climate conditions in Siberia. We conducted a factorial experiment using the LANDIS-II landscape disturbance and succession model. Treatments included varying the size and amount of areas cut and the cutting method (selective or clearcut). Simultaneously, the model simulated natural disturbances (fire, wind, insect outbreaks) and forest succession under projected future climate conditions as predicted by an ensemble of global circulation models. The cutting method and cutting rate treatments generally had a large effect on species and age-class composition, residual living biomass, and susceptibility to disturbance, whereas cutblock size had no effect. Cutblock size affected only measures of fragmentation, but cutting method and cutting rate often had an even greater effect. Based on the results, we simulated a “recommended” strategy and compared it with the current forest management practice. The recommended strategy resulted in greater forest biomass, increased abundance of favored species, and reduced fragmentation, but it did not significantly reduce losses by disturbance. No single strategy appears able to achieve all possible forest management objectives.
Armillaria species distribution and site relationships in Pinus- and Tsuga-dominated forests in Massachusetts
Authors: Brazee Nicholas J. , Wick Robert L.
Published: July 2011

The primary objective of this study was to determine the composition of Armillaria species in northeastern North American Pinus - and Tsuga -dominated forests. This was accomplished by sampling 32 plots at eight sites within pitch pine ( Pinus rigida Mill.), eastern white pine ( Pinus strobus L.), eastern white pine – mixed oak, and eastern hemlock ( Tsuga canadensis (L.) Carr.) forests. In total, 320 isolates were collected from 19 host tree species, with 207 of 320 (65%) of all isolations coming from Pinus and Tsuga. Armillaria solidipes Peck was the most abundant species, making up 188 of 320 (59%) of all isolations, which included 39 isolations from hardwoods. Meanwhile, Armillaria mellea (Vahl) P. Kumm. was collected a total of 27 times from eastern white and pitch pine. These two Armillaria species co-occurred at five of the eight sites sampled. Chi-square analyses showed that incidence of Armillaria species were significantly different by forest type. Pitch pine forests had a higher incidence of A. solidipes (p < 0.001), eastern white pine forests had a higher incidence of A. mellea (p = 0.001), and eastern hemlock forests had a higher incidence of Armillaria gallica Marxm. & Romagn. (p = 0.002) compared with expected values. The distribution of A. solidipes varied significantly by soil drainage and soil type, with a higher incidence on excessively drained (p < 0.001) and loamy sand (p < 0.001) soils.
The temporal development of old-growth structural attributes in second-growth stands: a chronosequence study in the Coastal Western Hemlock zone in British Columbia
Authors: Gerzon Michael , Seely Brad , MacKinnon Andy
Published: July 2011

One of the key issues facing forest resource planners is the conservation and recruitment of old-growth characteristics in managed forests. The paucity of long-term data sets in many regions has limited our ability to project the temporal patterns of structural development in second-growth forests. Age-based thresholds have been employed in some jurisdictions, but these lack flexibility and are arbitrary in nature. Here we conduct a chronosequence study consisting of second-growth and old-growth stands in the coastal forests of Vancouver Island, British Columbia, to identify structural attributes that are suitable for quantifying and monitoring the progressive development of old-growth characteristics. The following structural attributes were identified and evaluated in the chronosequence analysis: volume and density of large live stems, standard deviation of stem DBH, density of large-diameter snags, volume of woody debris, and understory vegetation cover. The rate at which old-growth structural characteristics developed in second-growth stands varied considerably, with the earliest reaching levels observed in old-growth stands within 112 years, while most requiring 200 to greater than 250 years. The use of quantifiable measures of old-growth structure will help forest managers plan for the continued protection and recruitment of old-growth structure within managed forest landscapes.
Detection of red heartwood in paper birch (Betula papyrifera) using external stem characteristics
Authors: Belleville Benoît , Cloutier Alain , Achim Alexis
Published: July 2011

Red heartwood, a dark nonhomogenous discolouration in paper birch trees ( Betula papyrifera Marsh.), limits the applications and uses of sawn boards to nonvisible low-value products, thus resulting in substantial value loss. The occurrence and distribution of red heartwood were investigated in 12 paper birch trees grown in the province of Quebec, Canada. The youngest tree was 62 years old at breast height and the oldest 86 years old for an average of 75 years old. In this study, 225 occurrences of external traits, relating to branch scars and forks, previously proposed as initiation points for red heartwood were identified and measured. The distribution of red heartwood was digitally mapped and the effect of these external traits on the red heartwood surface and shape inside each tree was examined. Results show that red heartwood initiates from an external trait and that multiple external traits can contribute to the development of a red heartwood column following the longitudinal axis of the stem. Red heartwood appeared to initiate mainly from external traits at the base of the tree. A modelling exercise indicated that the width of the red heartwood column inside a standing tree can be estimated from branch scar width and height from the ground. Tree vigour could not be linked to the proportion of red heartwood inside standing trees. A three-dimensional analysis of log shape could potentially be used to detect red heartwood presence in a log before processing to optimize the log sawing pattern.
Video-based characters
Authors: Xu Feng , Liu Yebin , Stoll Carsten , Tompkin James , Bharaj Gaurav , Dai Qionghai , Seidel Hans-Peter , Kautz Jan , Theobalt Christian
Published: July 2011

We present a method to synthesize plausible video sequences of humans according to user-defined body motions and viewpoints. We first capture a small database of multi-view video sequences of an actor performing various basic motions. This database needs to be captured only once and serves as the input to our synthesis algorithm. We then apply a marker-less model-based performance capture approach to the entire database to obtain pose and geometry of the actor in each database frame. To create novel video sequences of the actor from the database, a user animates a 3D human skeleton with novel motion and viewpoints. Our technique then synthesizes a realistic video sequence of the actor performing the specified motion based only on the initial database. The first key component of our approach is a new efficient retrieval strategy to find appropriate spatio-temporally coherent database frames from which to synthesize target video frames. The second key component is a warping-based texture synthesis approach that uses the retrieved most-similar database frames to synthesize spatio-temporally coherent target video frames. For instance, this enables us to easily create video sequences of actors performing dangerous stunts without them being placed in harm's way. We show through a variety of result videos and a user study that we can synthesize realistic videos of people, even if the target motions and camera views are different from the database content.
Efficient elasticity for character skinning with contact and collisions
Authors: McAdams Aleka , Zhu Yongning , Selle Andrew , Empey Mark , Tamstorf Rasmus , Teran Joseph , Sifakis Eftychios
Published: July 2011

We present a new algorithm for near-interactive simulation of skeleton driven, high resolution elasticity models. Our methodology is used for soft tissue deformation in character animation. The algorithm is based on a novel discretization of corotational elasticity over a hexahedral lattice. Within this framework we enforce positive definiteness of the stiffness matrix to allow efficient quasistatics and dynamics. In addition, we present a multigrid method that converges with very high efficiency. Our design targets performance through parallelism using a fully vectorized and branch-free SVD algorithm as well as a stable one-point quadrature scheme. Since body collisions, self collisions and soft-constraints are necessary for real-world examples, we present a simple framework for enforcing them. The whole approach is demonstrated in an end-to-end production-level character skinning system.