bluuebunny/crossref_metadata_2025 huggingface dataset:
Integrated plant phenotypic responses to contrasting above‐ and below‐ground resources: key roles of specific leaf area and root mass fraction
Authors: Freschet Grégoire T. , Swart Elferra M. , Cornelissen Johannes H. C.
Published: March 2015

Plants adapt phenotypically to different conditions of light and nutrient supply, supposedly in order to achieve colimitation of these resources. Their key variable of adjustment is the ratio of leaf area to root length, which relies on plant biomass allocation and organ morphology.

We recorded phenotypic differences in leaf and root mass fractions (LMF, RMF), specific leaf area (SLA) and specific root length (SRL) of 12 herbaceous species grown in factorial combinations of high/low irradiance and fertilization treatments.

Leaf area and root length ratios, and their components, were influenced by nonadditive effects between light and nutrient supply, and differences in the strength of plant responses were partly explained by Ellenberg's species values representing ecological optima. Changes in allocation were critical in plant responses to nutrient availability, as the RMF contribution to changes in root length was 2.5× that of the SRL. Contrastingly, morphological adjustments (SLA rather than LMF) made up the bulk of plant response to light availability.

Our results suggest largely predictable differences in responses of species and groups of species to environmental change. Nevertheless, they stress the critical need to account for adjustments in below‐ground mass allocation to understand the assembly and responses of communities in changing environments.
Viral pathogen production in a wild grass host driven by host growth and soil nitrogen
Authors: Whitaker Briana K. , Rúa Megan A. , Mitchell Charles E.
Published: March 2015

Nutrient limitation is a basic ecological constraint that has received little attention in studies on virus production and disease dynamics. Nutrient availability could directly limit the production of viral nucleic acids and proteins, or alternatively limit host growth and thus indirectly limit metabolic pathways necessary for viral replication.

In order to compare direct and indirect effects of nutrient limitation on virus production within hosts, we manipulated soil nitrogen (N) and phosphorus (P) availability in a glasshouse for the wild grass host Bromus hordeaceus and the viral pathogen Barley yellow dwarf virus‐PAV.

We found that soil N additions increased viral concentrations within host tissues, and the effect was mediated by host growth. Specifically, in statistical models evaluating the roles of host biomass production, leaf N and leaf P, viral production depended most strongly on host biomass, rather than the concentration of either nutrient. Furthermore, at low soil N, larger plants supported greater viral concentrations than smaller ones, whereas at high N, smaller plants supported greater viral concentrations.

Our results suggest that enhanced viral productivity under N enrichment is an indirect consequence of nutrient stimulation to host growth rate. Heightened pathogen production in plants has important implications for a world facing increasing rates of nutrient deposition.
Isoprenoids and phenylpropanoids are part of the antioxidant defense orchestrated daily by drought‐stressed Platanus × acerifolia plants during Mediterranean summers
Authors: Tattini Massimiliano , Loreto Francesco , Fini Alessio , Guidi Lucia , Brunetti Cecilia , Velikova Violeta , Gori Antonella , Ferrini Francesco
Published: March 2015

The hypothesis was tested that isoprenoids and phenylpropanoids play a prominent role in countering photooxidative stress, following the depletion of antioxidant enzyme activity in plants exposed to severe drought stress under high solar irradiance and high temperatures.

Platanus × acerifolia, a high isoprene‐emitting species, was drought‐stressed during summer (WS) and compared with unstressed controls (WW). Water relations and photosynthetic parameters were measured under mild, moderate, and severe drought stress conditions. Volatile and nonvolatile isoprenoids, antioxidant enzymes, and phenylpropanoids were measured with the same time course, but in four different periods of the day.

Drought severely inhibited photosynthesis, whereas it did not markedly affect the photochemical machinery. Isoprene emission and zeaxanthin concentration were higher in WS than in WW leaves, particularly at mild and moderate stresses, and during the hottest hours of the day. The activities of catalase and ascorbate peroxidase steeply declined during the day, while the activity of guaiacol peroxidase and the concentration of quercetin increased during the day, peaking in the hottest hours in both WW and WS plants.

Our experiment reveals a sequence of antioxidants that were used daily by plants to orchestrate defense against oxidative stress induced by drought and associated high light and high temperature. Secondary metabolites seem valuable complements of antioxidant enzymes to counter oxidative stress during the hottest daily hours.
Predicting risk for childhood asthma by pre‐pregnancy, perinatal, and postnatal factors
Authors: Wen Hui‐Ju , Chiang Tung‐Liang , Lin Shio‐Jean , Guo Yue Leon
Published: March 2015

Background

Symptoms of atopic disease start early in human life. Predicting risk for childhood asthma by early‐life exposure would contribute to disease prevention. A birth cohort study was conducted to investigate early‐life risk factors for childhood asthma and to develop a predictive model for the development of asthma.

Methods

National representative samples of newborn babies were obtained by multistage stratified systematic sampling from the 2005 Taiwan Birth Registry. Information on potential risk factors and children's health was collected by home interview when babies were 6 months old and 5 yr old, respectively. Backward stepwise regression analysis was used to identify the risk factors of childhood asthma for predictive models that were used to calculate the probability of childhood asthma.

Results

A total of 19,192 children completed the study satisfactorily. Physician‐diagnosed asthma was reported in 6.6% of 5‐yr‐old children. Pre‐pregnancy factors (parental atopy and socioeconomic status), perinatal factors (place of residence, exposure to indoor mold and painting/renovations during pregnancy), and postnatal factors (maternal postpartum depression and the presence of atopic dermatitis before 6 months of age) were chosen for the predictive models, and the highest predicted probability of asthma in 5‐yr‐old children was 68.1% in boys and 78.1% in girls; the lowest probability in boys and girls was 4.1% and 3.2%, respectively.

Conclusions

This investigation provides a technique for predicting risk of childhood asthma that can be used to developing a preventive strategy against asthma.
Silurian craniide brachiopods from Gotland
Authors: Holmer Lars E. , Popov Leonid , Bassett Michael G.
Published: March 2015

Seven craniide brachiopod genera are described from the Silurian (Wenlock–Ludlow) of Gotland, including one new genus and five new species. The new genus and species Thulecrania septicostata is unique among Silurian craniides as it possesses solid spines. The new species Lepidocrania multilamellosa is the first Silurian record of this poorly known Permian genus. The problematic North American Propatella Grubbs, , was originally described as a gastropod, but the new species Propatella palmaria from Gotland shows that it is a craniide with sutured hollow spines of a type not previously recorded from Silurian craniides. The dorsal valves of the new species Valdiviathyris? bicornis are remarkably similar to those of the type species and represent the first possible Palaeozoic record of this poorly known extant craniide. This first systematic study of craniide brachiopods from the Silurian of Gotland shows that the diversity is relatively high as compared to other known Silurian craniide faunas, but a more thorough comparison is not possible due to the lack of data from most parts of the world. The new data from Gotland support the view that the craniides were not affected by the end‐Ordovician extinction.
Sexual hybridization between Capsella bursa‐pastoris (L.) Medik (♀) and Camelina sativa (L.) Crantz (♂) (Brassicaceae)
Authors: Martin Sara L. , Sauder Connie A. , James Tracey , Cheung Kyle W. , Razeq Fakhria M. , Kron Paul , Hall Linda
Published: March 2015

The development of transgenic oilseed Camelina sativa (2n = 40) and the potential for hybridization with its weedy relative Capsella bursa‐pastoris (2n = 36) necessitates a careful evaluation of the reproductive compatibility between the species. Here, we conducted over 1800 crosses (emasculation and manual pollination) to examine the ability of 10 Canadian C. bursa‐pastoris (♀) accessions to hybridize with five accessions of C. sativa (♂). Seven hybrids were confirmed among 586 putative hybrids screened with species‐specific markers, indicating a hybridization rate of 1.5 hybrids per 10 000 ovules pollinated. All seven hybrids had intermediate DNA content compared to their parents, were morphologically distinct, had low (1.9%) pollen fertility and failed to produce selfed or backcrossed seed. Given the abundance of C. bursa‐pastoris along field margins, hybrids will likely be generated in the wild, but they will be unable to establish lineages unless fertility is restored. The large number of crosses and the diversity captured by the use of multiple accessions resulted in strong statistical power and a high degree of confidence in the estimated hybridization rate.
Risperidone long‐acting injection and 1‐year rehospitalization rate of schizophrenia patients: A retrospective cohort study
Authors: Chan Hsue‐Wei , Huang Chin‐Yu , Feng Wen‐Jui , Yen Yung‐Chieh
Published: March 2015

Aims

We wanted to present a picture of patients with schizophrenia receiving risperidone long‐acting injection (RLAI) treatment in a real‐world setting.

Methods

This was a retrospective cohort study; 379 patients with schizophrenia were enrolled and treated with different kinds of antipsychotic agents at E‐Da Hospital, and received a 12‐month follow up. The patients were distributed into three groups: the all‐oral antipsychotic, oral risperidone and RLAI groups. The antipsychotic agents and dosages they used were recorded. The rate of rehospitalization, length of hospital stay, emergency room visits and medical expenditures were assessed.

Results

The RLAI group had a significantly higher rate of hospitalization before enrolment (the all‐oral antipsychotic group was 32.1%, the oral risperidone group, 35.9%, and the RLAI group, 88.4%, P < 0.0001). After a 1‐year follow up, all three groups were similar in rehospitalization rates (the all‐oral antipsychotic group was 28.9%, the oral risperidone group, 30.1%, and the RLAI group, 30.2%, P > 0.999), length of hospital stay and number of emergency room visits during follow up. The most commonly used oral antipsychotics were risperidone (0.5–7 mg/day), quetiapine (65–1200 mg/day), and olanzapine (2–25 mg/day).

Conclusions

Using RLAI reduces the severity of disease in more difficult patients.
Palmoplantar Hyperkeratosis: A Rare Cutaneous Manifestation of Juvenile Dermatomyositis
Authors: Smith Vanessa M. , Leone Valentina , Clark Sheila
Published: March 2015

We report the case of a 12‐year‐old girl with juvenile dermatomyositis (JDM). She had a 12‐month history of palmoplantar hyperkeratosis that was initially treated as eczema. We wish to alert clinicians to this rare cutaneous manifestation of JDM.
Immune Dysregulation, Polyendocrinopathy, Enteropathy, X‐Linked Syndrome Associated with Neonatal Epidermolysis Bullosa Acquisita
Authors: Bis Sabina , Maguiness Sheilagh M. , Gellis Stephen E. , Schneider Lynda C. , Lee Pui Y. , Notarangelo Luigi D. , Keles Sevgi , Chatila Talal A. , Schmidt Birgitta A. , Miller Daniel D.
Published: March 2015

We report the case of a 2‐week‐old boy who presented with a vesiculopustular, bullous eruption in the setting of autoimmune enteropathy, hypothyroidism, membranous nephropathy, Coombs‐positive hemolytic anemia, and persistent eosinophilia. Immunologic testing revealed a deficiency of FOXP3‐expressing regulatory T cells, and a diagnosis of immune dysregulation, polyendocrinopathy, enteropathy, X‐linked syndrome was made. Histologic analysis, immunofluorescence, and enzyme‐linked immunosorbent assay confirmed the bullous eruption as epidermolysis bullosa acquisita with associated collagen VII autoantibody production. The skin lesions responded to systemic immunosuppressant therapy and have regressed after allogeneic bone marrow transplantation.
Successful Topical Rapamycin Treatment for Facial Angiofibromata in Two Children
Authors: Pynn Emma V. , Collins Jemma , Hunasehally Prasad R. Y. , Hughes Jenny
Published: March 2015

Topical sirolimus, or rapamycin, is known to inhibit tumorigenesis in tuberous sclerosis. We report two cases of successful treatment of children with facial angiofibromata and summarize the encouraging evidence of the effectiveness of this therapy in the literature.
Camptodactyly and Knuckle Pads Coexisting in an Adolescent Boy: Connection or Coincidence?
Authors: Corbo Michael D. , Weinstein Miriam
Published: March 2015

Camptodactyly is a condition characterized by a nontraumatic, fixed flexion contracture at the proximal interphalangeal joint, typically involving the fifth finger. Most occurrences are sporadic, but autosomal dominant transmission and syndromic associations have been described in the literature. We describe the case of an adolescent boy who presented to our clinic with a 2‐year history of bilateral, nonsyndromic camptodactyly and knuckle pads.
Coxsackie Eruption Arising in Areas of Epidermolytic Ichthyosis
Authors: Lewis Suzanna , Rico Tace
Published: March 2015

Coxsackie eruptions concentrated in areas of atopic dermatitis, a phenomenon termed “eczema coxsackium,” has been well described in the literature but, to our knowledge, the concentration of coxsackie viral lesions to areas of ichthyosis has not been reported. This case describes a rare presentation of coxsackie viral lesions concentrated in areas of epidermolytic ichthyosis in a 3‐year‐old boy.
Effects of Enhanced UV‐B Radiation on Biochemical Traits in Postharvest Flowers of Medicinal Chrysanthemum
Authors: Si Chao , Yao Xiao‐Qin , He Xue‐Li , Chu Jian‐Zhou , Ma Chun‐Hui , Shi Xiao‐Fei
Published: March 2015

This article reported UV‐B radiation effects on biochemical traits in postharvest flowers of chrysanthemum. The experiment included six levels of UV‐B radiation (UV0, 0 μW cm−2; UV50, 50 μW cm−2; UV200, 200 μW cm−2; UV400, 400 μW cm−2; UV600, 600 μW cm−2 and UV800, 800 μW cm−2). Enhanced UV‐B radiation significantly increased hydrogen peroxide content (except for UV50), but did not evidently affect malondialdehyde content in flowers. Chlorophyll b and total chlorophyll content were significantly increased by UV600 and UV800. UV400 and UV600 significantly increased anthocyanins, carotenoids and UV‐B absorbing compounds content, and the activities of phenylalanine ammonia lyase (PAL) and cinnamic acid‐4‐hydroxylase (C4H) over the control. 4‐coumarate CoA ligase (4CL) activity was significantly decreased by enhanced UV‐B radiation (except for UV50). The relationships between UV‐B radiation intensities and the activities of secondary metabolism enzymes were best described by a second‐order polynomial. The R2 values for UV‐B radiation intensities and the activities of PAL, C4H and 4CL were 0.8361, 0.5437 and 0.8025, respectively. The results indicated that enhanced UV‐B radiation could promote secondary metabolism processes in postharvest flowers, which might be beneficial for the accumulation of medically active ingredients in medicinal plants. The optimal UV‐B radiation intensities in the study were between UV400‐UV600.
The Usefulness of Captive Kept Capercaillie (Tetrao urogallusL.) as the Semen Donors for Artificial Insemination and Gene Pool PreservationIn vitro
Authors: Łukaszewicz ET , Kowalczyk AM
Published: March 2015

Contents

Captive breeding of birds threatened by extinction in zoological gardens or other closed aviary centres is one of the methods allowing their protection and gene pool preservationex situ in vivo. Such birds are usually kept in captivity lifelong and serve as parents of several new generations that can be further released into natural environment, or males are used as semen donors for artificial insemination and gene banking. Therefore, the fecundity of such flocks (number of laid egg and spermatozoa quantity and quality) is very important. The aim of this study was to evaluate the usefulness of captive kept capercaillie (Tetrao urogallusL.) as semen donors in three subsequent reproductive seasons, based on the assessment of manually collected semen quality. Male response to dorso‐abdominal massage, ejaculate volume, sperm concentration, motility and morphology were evaluated individually at three succeeding years. Depending on individual male properties and year of collection, the number of positive reactions to semen collection attempts (i.e. ending with ejaculation) varied from 44.4% to 100.0%; single ejaculate volume ranged from 10 to 300 μl, spermatozoa concentration from 10 × 106per ml to 3520 × 106per ml and percentage of live morphologically normal spermatozoa from 19.3 to 80.3%. The highest average value (66.7) of semen quality factor (SQF) was noted for a 2‐year‐old male (varying from 1.9 to 258.1), while the lowest for ten‐ (4.8; varying from 0.1 to 17.0) and 7‐year‐old (6.6; varying between 0.6 and 13.6). Assuming that forAIpurposes, the ejaculate quality has to be at minimum 10SQF, obtained results indicate that majority of capercaillie kept in captivity, both young (2–3 years old) and older (up to 10 years old), can be valuable semen producers in succeeding seasons.
Expression of Heparin‐Binding EGF‐Like Growth Factor (HB‐EGF) in Bovine Endometrium: Effects of HB‐EGF and Interferon‐τ on Prostaglandin Production
Authors: Takatsu K , Acosta TJ
Published: March 2015

Contents

Heparin‐binding EGF‐like growth factor (HB‐EGF) regulates several cell functions by binding to its membrane receptor (ErbB1 and ErbB4). Experimental evidences suggest that HB‐EGF, prostaglandins (PGs) and interferon‐τ (IFN‐τ) regulate uterine function for pregnancy establishment in ruminants. In this study, the mRNA expressions of HB‐EGF, ErbB1 and ErbB4 in bovine endometrium and the effects of HB‐EGF and IFN‐τ on PGE2 and PGF2‐α production by endometrial cells were investigated. RT‐PCR analysis revealed that HB‐EGF mRNA was greater at the mid‐luteal stage than at the early and regressed luteal stages (p < 0.05). ErbB1 mRNA expression was greater at the mid‐ and late luteal stages than at the other luteal stages (p < 0.05). IFN‐τ increased the expression of HB‐EGF, ErbB1 and ErbB4 mRNA in epithelial cells (p < 0.05). HB‐EGF did not affect PGF2‐α or PGE2 production by bovine endometrial epithelial cells, but increased PGF2‐α and PGE2 production by bovine endometrial stromal cells (p < 0.05). IFN‐τ significantly decreased HB‐EGF‐stimulated PGF2‐α (p < 0.05), but not PGE2 (p > 0.05) production by stromal cells. These results indicate that HB‐EGF and its receptors expression changed in bovine endometrium throughout the oestrous cycle. IFN‐τ increased their expression in cultured endometrial cells. HB‐EGF and IFN‐τ have the ability to regulate PGs production by stromal cells and therefore may play a role in the local regulation of uterine function at the time of implantation in cattle.
A Joint Model of Persistent Human Papilloma Virus Infection and Cervical Cancer Risk: Implications for Cervical Cancer Screening
Authors: Katki Hormuzd A. , Cheung Li C. , Fetterman Barbara , Castle Philip E. , Sundaram Rajeshwari
Published: March 2015

New cervical cancer screening guidelines in the USA and many European countries recommend that women are tested for human papilloma virus (HPV). To inform decisions about screening intervals, we calculate the increase in precancer or cancer risk per year of continued HPV infection. However, both time to onset of precancer or cancer and time to HPV clearance are interval censored, and onset of precancer or cancer strongly informatively censors HPV clearance. We analyse these bivariate informatively interval-censored data by developing a novel joint model for time to clearance of HPV and time to precancer or cancer by using shared random effects, where the estimated mean duration of each woman's HPV infection is a covariate in the submodel for time to precancer or cancer. The model was fitted to data on 9553 HPV positive and negative women undergoing cervical cancer screening at Kaiser Permanente Northern California: data that were pivotal to the development of US screening guidelines. We compare the implications for screening intervals of this joint model with those from population-average marginal models of precancer or cancer risk. In particular, after 2 years the marginal population-average precancer or cancer risk was 5%, suggesting a 2-year interval to control population-average risk at 5%. In contrast, the joint model reveals that almost all women exceeding 5% individual risk in 2 years also exceeded 5% in 1 year, suggesting that a 1-year interval is better to control individual risk at 5%. The example suggests that sophisticated risk models that can predict individual risk may have implications that are different from those of population-average risk models that are currently used for informing medical guideline development.
Do Parenting and Family Characteristics Moderate the Relation between Peer Victimization and Antisocial Behavior? A 5‐year Longitudinal Study
Authors: Yang Grace S. , McLoyd Vonnie C.
Published: March 2015

Past research has demonstrated that relationships with peers and parents play salient roles in various child outcomes. However, little research has examined the confluence of these two factors in the context of peer victimization. In particular, little is known about which family and parental factors mitigate or intensify the impact of adverse peer relations. The current study bridged this gap by testing whether maternal support and family conflict moderated the association between peer victimization and antisocial behavior. Moderation effects were found for girls but not boys. Cross‐lagged path analyses of nationally representative longitudinal data (N = 1046; 53 percent boys; Time 1: Mage = 10.7) showed that, among girls, higher levels of maternal warmth and mother–child communication significantly attenuated the link between early peer victimization and later antisocial outcomes. By contrast, greater family conflict significantly increased antisocial outcomes among girls who experienced peer victimization. For boys, early peer victimization significantly predicted antisocial outcomes, regardless of parenting and family factors. All findings remained significant even after controlling for preexisting antisocial tendencies and demographic factors, as well as for the stability of victimization in the model.
Co‐producing Approaches to the Management of Dementia through Social Prescribing
Authors: Baker Keith , Irving Adele
Published: March 2015

A promising approach to the management of dementia is ‘social prescribing’. Social prescribing is a form of ‘co‐production’ that involves linking patients with non‐clinical activities, typically delivered by voluntary and community groups, in an effort to improve their sense of well‐being. The success of social prescribing depends upon the ability of boundary‐spanning individuals within service delivery organizations to develop referral pathways and collaborative relationships through ‘networks’. This article examines the operation of a pilot social prescribing programme in the North East of England, targeted at older people with early onset dementia and depression, at risk of social isolation. It is argued that the scheme was not sustained, in part, because the institutional logics that governed the actions of key boundary‐spanning individuals militated against the collaboration necessary to support co‐production.
Dose–response modelling for bivariate covariates with and without a spike at zero: theory and application to binary outcomes
Authors: Lorenz E. , Jenkner C. , Sauerbrei W. , Becher H.
Published: March 2015

In epidemiology and clinical research, there is often a proportion of unexposed individuals resulting in zero values of exposure, meaning that some individuals are not exposed and those exposed have some continuous distribution. Examples are smoking or alcohol consumption. We will call these variables with a spike at zero (SAZ). In this paper, we performed a systematic investigation on how to model covariates with a SAZ and derived theoretical odds ratio functions for selected bivariate distributions. We consider the bivariate normal and bivariate log normal distribution with a SAZ. Both confounding and effect modification can be elegantly described by formalizing the covariance matrix given the binary outcome variable Y. To model the effect of these variables, we use a procedure based on fractional polynomials first introduced by Royston and Altman (1994, Applied Statistics 43: 429–467) and modified for the SAZ situation (Royston and Sauerbrei, 2008, Multivariable model‐building: a pragmatic approach to regression analysis based on fractional polynomials for modelling continuous variables, Wiley; Becher et al., 2012, Biometrical Journal 54: 686–700). We aim to contribute to theory, practical procedures and application in epidemiology and clinical research to derive multivariable models for variables with a SAZ. As an example, we use data from a case–control study on lung cancer.
Pneumococcal carriage in rural Gambia prior to the introduction of pneumococcal conjugate vaccine: a population‐based survey
Authors: Usuf Effua , Badji Henry , Bojang Abdoulie , Jarju Sheikh , Ikumapayi Usman Nurudeen , Antonio Martin , Mackenzie Grant , Bottomley Christian
Published: March 2015

Objective

To evaluate pneumococcal colonisation before and after the introduction of pneumococcal conjugate vaccine (PCV) in eastern Gambia.

Methods

Population‐based cross‐sectional survey of pneumococcal carriage between May and August 2009 before the introduction of PCV into the Expanded Program on Immunization. Nasopharyngeal swabs were collected from all household members, but in selected households, only children aged 6–10 years were swabbed. This age group participated in an earlier trial of a nine‐valent PCV between 2000 and 2004.

Results

The prevalence of nasopharyngeal pneumococcal carriage in 2933 individuals was 72.0% in underfives (N = 515), 41.6% in children aged 5–17 (N = 1508) and 13.0% in adults ≥18 (N = 910) years. The age‐specific prevalence of serotypes included in PCV7, PCV10 and PCV13 was 24.7%, 26.6% and 46.8% among children <5 years of age; 8.5%, 9.2% and 17.7% among children 5–17 years; and 2.5%, 3.3% and 5.5% among adults ≥18 years. The most common serotypes were 6A (13.1%), 23F (7.6%), 3 (7.3%), 19F (7.1%) and 34 (4.6%). There was no difference in the overall carriage of pneumococci between vaccinated and unvaccinated children 8 years after the primary vaccination with three doses of PCV (48.3% vs. 41.1%).

Conclusion

Before the introduction of PCV, serotypes included in PCV13 accounted for about half the pneumococcal serotypes in nasopharyngeal carriage. Thus, the potential impact of PCV13 on pneumococcal disease in the Gambia is substantial.
Implementation of a novel real‐time platelet inventory management system at a multi‐site transfusion service
Authors: Gomez Alwyn Titus , Quinn Jason George , Doiron Donald Joseph , Watson Stephanie , Crocker Bryan David , Cheng Calvino Ka‐Wing
Published: March 2015

BACKGROUND

Blood platelets (PLTs) are a valuable commodity. Management of their inventory has implications both for patient care and for the cost of health care delivery. There are a variety of different methods of managing PLT inventory currently in practice and multiple theoretical models aimed at improving PLT inventory metrics. In this study we evaluate the ability of a novel electronic dashboard system that monitors and displays both PLT inventory and patient data to improve transfusion metrics at a quaternary health care center.

STUDY DESIGN AND METHODS

The Capital District Health Authority is a quaternary health care center that transfuses approximately 2500 PLT units annually. To improve PLT discard rates a novel, low‐overhead system that interfaces with the laboratory information system and displays real‐time data between transfusion sites on PLT inventory and orders was implemented in November 2011. This study examines the transfusion quality metrics data from the 24 months before and after implementation.

RESULTS

A significant reduction in mean monthly PLT outdate rate was observed after the implementation of the PLT dashboard suite from 24.5% (n = 24, SD ± 6.4%) to 15.1% (n = 24, SD ± 6.4%; p < 0.001). PLT age at time of transfusion was also reduced from 3.60 days (n = 4796, SD ± 0.97 days) to 3.46 days (n = 4881, SD ± 1.00 days; p < 0.001).

CONCLUSIONS

This study describes the implementation of a novel PLT dashboard suite. This suite significantly reduced PLT outdate rates at our institution over the 48‐month study period.
Prospective, Randomized Comparison of the Effect of Two Antimicrobial Regimes on Surgical Site Infection Rate in Dogs Undergoing Orthopedic Implant Surgery
Authors: Aiken Miranda J. , Hughes Thomas K. , Abercromby Ralph H. , Holmes Mark A. , Anderson Angus A.
Published: March 2015

Objectives

To determine whether extending prophylactic antimicrobial administration into the postoperative period would decrease the surgical site infection (SSI) rate in clean canine orthopedic surgery associated with a metal implant.

Study Design

Randomized prospective clinical study.

Sample Population

Consecutive procedures (n = 400) on dogs that had clean orthopedic surgery using a metal implant.

Methods

Cases were randomly allocated to 1 of 2 groups. Group 1 was only administered perioperative antimicrobial drugs whereas group 2 was administered perioperative and 5 days of postoperative antimicrobial therapy. Owners were questioned or dogs were examined at 2 and 6 weeks after surgery to identify any SSI. Long term follow‐up by questionnaire of the referring veterinary surgeon ≥1 year after surgery was obtained.

Results

Ten of 191 dogs (5.24%) in group 1 developed SSI within 6 weeks compared with 7 of 198 (3.54%) in group 2; 7.22% of dogs in group 1 and 8.24% in group 2 developed infections more than 6 weeks after surgery.

Conclusions

SSI rates in this population of dogs were similar where antimicrobial prophylaxis was administered perioperatively over 3 hours or as a course continued for 6 days.
Inhibition of presynaptic calcium transients in cortical inputs to the dorsolateral striatum by metabotropic GABAB and mGlu2/3 receptors
Authors: Kupferschmidt David A. , Lovinger David M.
Published: March 2015

Key points

Plastic changes at cortical inputs to the dorsolateral striatum (DLS) underlie skill learning and habit formation, so characterizing the mechanisms by which these inputs are regulated is important for understanding the neural basis of action control.

We developed a novel approach using the genetically encoded calcium (Ca2+) indicator GCaMP6 and brain slice photometry to assess evoked presynaptic Ca2+ transients in cortical inputs to the DLS and study their regulation by GABAB and mGlu2/3 receptors.

GABAB and mGlu2/3 receptor activation caused clear reductions in electrical stimulus‐evoked presynaptic Ca2+ transients in corticostriatal inputs to the DLS.

Functional P/Q‐type voltage‐gated Ca2+ channels were required for the normal inhibitory action of corticostriatal mGlu2/3 receptors.

We provide direct evidence of presynaptic Ca2+ inhibition by G protein‐coupled receptors at corticostriatal projections.

Cortical inputs to the dorsolateral striatum (DLS) are dynamically regulated during skill learning and habit formation, and are dysregulated in disorders characterized by impaired action control. Therefore, a mechanistic investigation of the processes regulating corticostriatal transmission is key to understanding DLS‐associated circuit function, behaviour and pathology. Presynaptic GABAB and group II metabotropic glutamate (mGlu2/3) receptors exert marked inhibitory control over corticostriatal glutamate release in the DLS, yet the signalling pathways through which they do so are unclear. We developed a novel approach using the genetically encoded calcium (Ca2+) indicator GCaMP6 to assess presynaptic Ca2+ in corticostriatal projections to the DLS. Using simultaneous photometric presynaptic Ca2+ and striatal field potential recordings, we report that relative to P/Q‐type Ca2+ channels, N‐type channels preferentially contributed to evoked presynaptic Ca2+ influx in motor cortex projections to, and excitatory transmission in, the DLS. Activation of GABAB or mGlu2/3 receptors inhibited both evoked presynaptic Ca2+ transients and striatal field potentials. mGlu2/3 receptor‐mediated depression did not require functional N‐type Ca2+ channels, but was attenuated by blockade of P/Q‐type channels. These findings reveal presynaptic mechanisms of inhibitory modulation of corticostriatal function that probably contribute to the selection and shaping of behavioural repertoires.
Decreases in mitochondrial reactive oxygen species initiate GABAA receptor‐mediated electrical suppression in anoxia‐tolerant turtle neurons
Authors: Hogg David W. , Pamenter Matthew E. , Dukoff David J. , Buck Leslie T.
Published: March 2015

Key points

Anoxia induces hyper‐excitability and cell death in mammalian brain but in the western painted turtle (Chrysemys picta bellii) enhanced GABA transmission prevents injury.

The mechanism responsible for increased GABA transmission is unknown; however, reactive oxygen species (ROS) generated by mitochondria may play a role because this is an oxygen‐sensitive process.

In this study, we show that inhibition of mitochondrial ROS production is sufficient to initiate a redox‐sensitive GABA signalling cascade that suppresses pyramidal neuron action potential frequency.

These results further our understanding of the turtle's unique strategy for reducing ATP consumption during anoxia and highlights a natural mechanism in which to explore therapies to protect mammalian brain from low‐oxygen insults (e.g. cerebral stroke).

Anoxia induces hyper‐excitability and cell death in mammalian brain but in the anoxia‐tolerant western painted turtle (Chrysemys picta bellii) neuronal electrical activity is suppressed (i.e. spike arrest), adenosine triphosphate (ATP) consumption is reduced, and cell death does not occur. Electrical suppression is primarily the result of enhanced γ‐aminobutyric acid (GABA) transmission; however, the underlying mechanism responsible for initiating oxygen‐sensitive GABAergic spike arrest is unknown. In turtle cortical pyramidal neurons there are three types of GABAA receptor‐mediated currents: spontaneous inhibitory postsynaptic currents (IPSCs), giant IPSCs and tonic currents. The aim of this study was to assess the effects of reactive oxygen species (ROS) scavenging on these three currents since ROS levels naturally decrease with anoxia and may serve as a redox signal to initiate spike arrest. We found that anoxia, pharmacological ROS scavenging, or inhibition of mitochondrial ROS generation enhanced all three types of GABA currents, with tonic currents comprising ∼50% of the total current. Application of hydrogen peroxide inhibited all three GABA currents, demonstrating a reversible redox‐sensitive signalling mechanism. We conclude that anoxia‐mediated decreases in mitochondrial ROS production are sufficient to initiate a redox‐sensitive inhibitory GABA signalling cascade that suppresses electrical activity when oxygen is limited. This unique strategy for reducing neuronal ATP consumption during anoxia represents a natural mechanism in which to explore therapies to protect mammalian brain from low‐oxygen insults.
Temporal and Spatial Variations of Wall Shear Stress in the Entrance Region of Microvessels
Authors: Oulaid Othmane , Zhang Junfeng
Published: March 2015

Using a simplified two-dimensional divider-channel setup, we simulate the development process of red blood cell (RBC) flows in the entrance region of microvessels to study the wall shear stress (WSS) behaviors. Significant temporal and spatial variation in WSS is noticed. The maximum WSS magnitude and the strongest variation are observed at the channel inlet due to the close cell-wall contact. From the channel inlet, both the mean WSS and variation magnitude decrease, with a abrupt drop in the close vicinity near the inlet and then a slow relaxation over a relatively long distance; and a relative stable state with approximately constant mean and variation is established when the flow is well developed. The correlations between the WSS variation features and the cell free layer (CFL) structure are explored, and the effects of several hemodynamic parameters on the WSS variation are examined. In spite of the model limitations, the qualitative information revealed in this study could be useful for better understanding relevant processes and phenomena in the microcirculation.
An Innovative Design of Artificial Knee Joint Actuator With Energy Recovery Capabilities
Authors: Alò Roberta , Bottiglione Francesco , Mantriota Giacomo
Published: March 2015

The actuation systems of lower limbs exoskeletons have been extensively investigated and, presently, a great effort is aimed at reducing the weight and improving the efficiency, thus increasing the operating range for battery-operated devices. In this work, an innovative and more efficient actuation system to power the knee joint is proposed. The key and nonconventional elements of this alternative design are a flywheel and a micro infinitely variable transmission (IVT). This particular powertrain configuration permits to exploit efficiently the dynamics of human locomotion, which offers the possibility to recover energy. By means of simulations of level ground walking and running, it is here demonstrated how storing energy in the flywheel permits to reduce the energy consumption and to downsize the electric motor.
Developing World Users as Lead Users: A Case Study in Engineering Reverse Innovation
Authors: Judge Benjamin M. , Hölttä-Otto Katja , Winter Amos G.
Published: March 2015

This paper examines the “reverse innovation” of the leveraged freedom chair (LFC), a high-performance, low-cost, off-road wheelchair originally designed for developing countries. A needs study of 71 developed world wheelchair users was conducted through three different data collection efforts. These data were contrasted with studies of 125 developing world wheelchair users, who were shown to be lead users for their developed world counterparts. The GRIT freedom chair (GFC), the developed world version of the LFC, was designed based on results of the study. By recognizing developing country users as lead users, designers can reveal latent needs and create globally disruptive innovations.
Magneto-Gas Kinetic Method for Nonideal Magnetohydrodynamics Flows: Verification Protocol and Plasma Jet Simulations
Authors: Araya Daniel B. , Ebersohn Frans H. , Anderson Steven E. , Girimaji Sharath S.
Published: March 2015

In this work, the gas-kinetic method (GKM) is enhanced with resistive and Hall magnetohydrodynamics (MHD) effects. Known as MGKM (for MHD–GKM), this approach incorporates additional source terms to the momentum and energy conservation equations and solves the magnetic field induction equation. We establish a verification protocol involving numerical solutions to the one-dimensional (1D) shock tube problem and two-dimensional (2D) channel flows. The contributions of ideal, resistive, and Hall effects are examined in isolation and in combination against available analytical and computational results. We also simulate the evolution of a laminar MHD jet subject to an externally applied magnetic field. This configuration is of much importance in the field of plasma propulsion. Results support previous theoretical predictions of jet stretching due to magnetic field influence and azimuthal rotation due to the Hall effect. In summary, MGKM is established as a promising tool for investigating complex plasma flow phenomena.
Application of Turbine Torsional Oscillation Damping Controller to Static Var Compensator
Authors: Ghorbani Amir , Arablu Masoud
Published: March 2015

This paper proposes a new auxiliary turbine torsional oscillation damping controller (TTODC) for static var compensator (SVC) to dampen out subsynchronous oscillations in power systems containing series compensated transmission lines. A new TTODC algorithm on the basis of synchronized phasor measurements received from phasor measurement units (PMUs) is presented. The idea of using remote signals obtained from PMU to dampen subsynchronous resonance (SSR) presented, too. An auxiliary TTODC is proposed for a SVC, using the generator rotor speed deviation signal as the stabilizing and remote signal to dampen subsynchronous oscillations. The performance of the controller is verified in a detailed nonlinear system considering eigenvalue analysis and transient simulations. Sturdiness of the controller is examined by applying the disturbances in the system that causes significant changes in generator's operating point. The IEEE second benchmark (SBM) model is used for the analysis and the SVC is simulated using the power system blockset (PSB) in the matlab/simulink environment.
Noninvasive In Vivo Determination of Residual Strains and Stresses
Authors: Donmazov Samir , Piskin Senol , Pekkan Kerem
Published: March 2015

Vascular growth and remodeling during embryonic development are associated with blood flow and pressure induced stress distribution, in which residual strains and stresses play a central role. Residual strains are typically measured by performing in vitro tests on the excised vascular tissue. In this paper, we investigated the possibility of estimating residual strains and stresses using physiological pressure–radius data obtained through in vivo noninvasive measurement techniques, such as optical coherence tomography or ultrasound modalities. This analytical approach first tested with in vitro results using experimental data sets for three different arteries such as rabbit carotid artery, rabbit thoracic artery, and human carotid artery based on Fung’s pseudostrain energy function and Delfino’s exponential strain energy function (SEF). We also examined residual strains and stresses in the human swine iliac artery using the in vivo experimental ultrasound data sets corresponding to the systolic-to-diastolic region only. This allowed computation of the in vivo residual stress information for loading and unloading states separately. Residual strain parameters as well as the material parameters were successfully computed with high accuracy, where the relative errors are introduced in the range of 0–7.5%. Corresponding residual stress distributions demonstrated global errors all in acceptable ranges. A slight discrepancy was observed in the computed reduced axial force. Results of computations performed based on in vivo experimental data obtained from loading and unloading states of the artery exhibited alterations in material properties and residual strain parameters as well. Emerging noninvasive measurement techniques combined with the present analytical approach can be used to estimate residual strains and stresses in vascular tissues as a precursor for growth estimates. This approach is also validated with a finite element model of a general two-layered artery, where the material remodeling states and residual strain generation are investigated.
Asymmetrical formation of etching residues and their roles in inner-gate-recessed-channel-array-transistor
Authors: Park Segeun , Son Youngwoong , Han Sangyeon , Kim Ilgweon , Roh Yonghan
Published: March 2015

Different etching rates subjected to the poly-Si/W gate-stacks of state-of-the-art inner-gate-recessed-channel-array-transistor under HBr/O2 plasma environment result in the asymmetrical SiBrx deposition on the sidewalls of the gate-stacks, causing both the fluctuation of the critical dimension (CD) and the degradation of electrical properties as a consequence. If a HF cleaning process either cannot completely remove SiBrx or was postponed for a certain period of time after finishing the reactive ion etching of the gate-stacks, asymmetrically deposited SiBrx residue unexpectedly reacted with air to form the oxidized etching residue such as SiOxBry. The growth of SiOxBry film on the sidewalls can eventually affect the gate CD and the overlap capacitance, resulting in the degradation of both saturation current and propagation time (tPD). A simple model for the diffusion of the SiBrx by-product during the asymmetrical etching process and the growth of SiOxBry film as a function of time delay is suggested.
Structural and optical properties of low temperature grown AlN films on sapphire using helicon sputtering system
Authors: Chen Meei-Ru , Chen Hou-Guang , Kao Hui-Ling , Wu Ming-Guei , Tzou An-Jye , Chen Jyh Shin , Chou Hsiung
Published: March 2015

AlN thin films have been deposited directly on c-plane sapphire substrates at low temperatures by a helicon sputtering system. The structural quality of AlN epitaxial films was characterized by x-ray diffractometry and transmission electron microscopy. The films exhibit smooth surface with root-mean-square roughness as small as 0.7 nm evaluated by atomic force microscope. The optical transmittance spectra show a steep absorption edge at the wavelength of 200 nm and a high transmittance of over 80% in the visible range. The band-edge transition (6.30 eV) of AlN film was observed in the cathodoluminescence spectrum recorded at 11 K. The spectral response of metal–semiconductor–metal photodetectors constructed with AlN/sapphire reveals the peak responsivity at 200 nm and a UV/visible rejection ratio of about two orders of magnitude. The results of this low temperature deposition suggest the feasibility of the epitaxial growth of AlN on sapphire substrates and the incorporation of the AlN films in the surface acoustic wave devices and the optical devices at deep ultraviolet region.