bluuebunny/crossref_metadata_2025 huggingface dataset:
Impact on Modes of Inheritance and Relative Risks of Using Extreme Sampling When Designing Genetic Association Studies
Authors: Zheng Gang , Jinfeng Xu , Yuan Ao , Colin O. Wu
Published: November 2012

Using extreme phenotypes for association studies can improve statistical power . We study the impact of using samples with extremely high or low traits on the alternative model space, the genotype relative risks, and the genetic models in association studies. We prove the following results: when the risk allele causes high‐trait values, the more extreme the high traits, the larger the genotype relative risks, which is not always true for using extreme low traits; we also prove that a genetic model theoretically changes with more extreme trait except for the recessive or dominant models. Practically, however, the impact of deviations from the true genetic model at a functional locus due to selective sampling is virtually negligible. The implications of our findings are discussed. Numerical values are reported for illustrations.
Agricultural price transmission across space and commodities during price bubbles
Authors: Esposti Roberto , Listorti Giulia
Published: November 2012

This article investigates agricultural price transmission during price bubbles. The empirical approach concerns the horizontal transmission of cereal prices both across different market places and across different commodities. The trade policy intervention put forward to mitigate the impact of price exuberance is considered. The analysis is performed using Italian and international weekly spot (cash) price data over years 2006–2010, a period of generalized turbulence of agricultural markets. Firstly, the properties of price time series are explored; then, interdependence across prices is specified and estimated by adopting appropriate cointegration techniques. Results suggest that the bubble had only a slight impact on the price spread and the temporary trade‐policy measure, when effective, has limited this impact.
How insects sense olfactory patches – the spatial scaling of olfactory information
Authors: Andersson Petter , Löfstedt Christer , Hambäck Peter A.
Published: November 2012

When searching for resources in heterogeneous environments, animals must rely on their abilities to detect the resources via their sensory systems. However, variation in the strength of the sensory cue may be mediated by the physical size of the resource patch. Patch detection of insects are often predicted by the scaling of sensory cues to patch size, where visual cues has been proposed to scale proportional to the diameter of the patch. The scaling properties of olfactory cues are, however, virtually unknown. Here, we investigated scaling rules for olfactory information in a gradient of numbers of odour sources, relevant to odour‐mediated attraction under field conditions. We recorded moth antennal responses to sex pheromones downwind from pheromone patches and estimated the slope in the scaling relationship between the effective length of the odour plumes and the number of odour sources. These measurements showed that the effective plume length increased proportional to the square root of the number of odour sources. The scaling relationship, as estimated in the field experiment, was then evaluated against field data of the slope in the relationship between trap catch and release rate of chemical attractants for a wide range of insects. This meta‐analysis revealed an average slope largely consistent with the estimated scaling relationship between the effective plume length and the number of odour sources. This study is the first to estimate the scaling properties of olfactory cues empirically and has implications for understanding and predicting the spatial distributions of insects searching by means of olfactory cues in heterogeneous environments.
The discovery of species–abundance distribution in an ecological community
Authors: Doi Hideyuki , Mori Terutaka
Published: November 2012

Species–abundance distribution (SAD) is one of the most basic descriptions of an ecological community. Vigorous controversy surrounded SAD from the 1940s to 1960s, and has since persisted. Isao Motomura first published a notable paper in 1932 to describe findings on SAD, and to provide an empirical model; nevertheless, this work has often been overlooked or incorrectly cited, probably due to being published in Japanese. Here, we introduce the works of Motomura with an English translation of the paper, and the subsequent research history of SAD. We also introduce the work of Numata et al., another Japanese paper, which provided the biological explanation for Motomura’s model of SAD, although it was rarely cited by subsequent studies. We summarize that Motomura was the first to fit a statistical model to observed SAD, and that Numata et al. attempted to explain the observed SAD via underlying biological mechanisms.
Caecal abnormality in a layer hen (Gallus gallus forma domestica) not accompanied by deficits in digestive performance or egg productivity
Authors: COURTNEY JONES Stephanie K. , MUNN Adam J.
Published: November 2012

We report a case of a layer hen (Gallus gallus forma domestica) with deviation in the morphology of the caecum, and unique opportunity to investigate the digestive performance of the animal compared with normal hens. In a study investigating digestive and reproductive performance, an atypical caecal arrangement was found in a hen that was unremarkable in regards to body mass, digestive performance and egg productivity in comparison to other hens fed a similar diet. Examination of the gastrointestinal tract revealed a singular tubular outgrowth from the ileo‐caecal junction, rather than the typical paired outgrowths. The single caecal duct bifurcated into two separate blind‐ended sacs. Similar caecal deviations have been described in adult and juveniles, but no indications of animal performance were reported in these cases. We conclude that if the presence of an abnormal caecal arrangement reduces digestive abilities they were not obvious, and some compensatory mechanism/s may exist. Alternatively, the abnormal caecal arrangement of our hen might function adequately, such that no compensation in feed intakes or reduced egg productivity was required or observed.
Effects of Bacillus subtilis B10 spores on viability and biological functions of murine macrophages
Authors: Huang Qin , Xu Xin , Mao Yu‐long , Huang Yi , Rajput Imran R. , Li Wei‐fen
Published: November 2012

This study was conducted to investigate the effects of Bacillus subtilis B10 spores on the viability and biological functions of murine macrophage. RAW 264.7 cells were stimulated both with and without B. subtilis B10 spores for 12 h. Then cell viability was determined to evaluate the cytotoxic effect of B. subtilis B10 spores to the cells, and the activities of acid phosphatase (ACP) and lactate dehydrogenase (LDH), the production of nitric oxide (NO) and inducible nitric oxide synthase (iNOS), and the secretion of inflammatory cytokines were measured to analyze the functions of macrophages. The results showed that B. subtilis B10 spores were not harmful to RAW 264.7 cells and they also strongly enhanced the activities of ACP and LDH (P < 0.01), remarkably increased NO and iNOS production (P < 0.01), and significantly stimulated the secretion of pro‐inflammatory cytokines, including tumor necrosis factor‐alpha (TNF‐α), interferon‐gamma (IFN‐γ), interleukin‐1 beta (IL‐1β), IL‐6, IL‐8 and IL‐12 (P < 0.01) while they reduced anti‐inflammatory cytokine IL‐10 (P < 0.01). The outcomes suggest that B. subtilis B10 spores are not only safe for murine macrophages, but also can activate these cells and enhance their immune function. The above findings suggest that B. subtilis B10 spores are potentially probiotic.
Direct restorative treatment of anterior weared teeth after re‐establishment of occlusal vertical dimension: a case report
Authors: Humel Maria M.C. , Takahashi Jessica M.F.K. , Paulillo Luis A.M.S. , Mesquita Marcelo F. , Martins Luis R.M.
Published: November 2012

doi: 10.1111/j.1741‐2358.2012.00630.x

Direct restorative treatment of anterior weared teeth after re‐establishment of occlusal vertical dimension: a case report

Objective:  The loss of posterior teeth resulting in a lack of stability may lead to excessive mandibular load on some points of occlusion of the remaining teeth, causing wear. The rehabilitation of these cases must be carefully planned and the treatment requires a period of adaptation with a new vertical dimension.

Background:  This case report describes the treatment of a patient with a loss of almost all posterior inferior teeth and a consequential loss of occlusal vertical dimension and accentuated wear of anterior elements.

Materials and methods:  Provisional removable partial dentures were manufactured and the patient used them for a period of adaptation prior to restoration of the anterior teeth. After the patient’s adaptation with the new occlusal dimension, anterior restorations were made using a mycrohibrid resin composite with different color aspects for an optimal stratification.

Results:  The restorations achieved an aesthetic configuration with ideal function as the final result and the occlusion showed a satisfactory stability for a provisional removable partial dentures.

Conclusion:  This article presents an anterior direct rehabilitation approach not only as an alternative option, but also as viable and less expensive treatment option with an optimally aesthetic and functional result.
Open tibial fractures grade IIIC treated successfully with external fixation, negative‐pressure wound therapy and recombinant human bone morphogenetic protein 7
Authors: Babiak Ireneusz
Published: November 2012

The aim of the therapy in open tibial fractures grade III was to cover the bone with soft tissue and achieve healed fracture without persistent infection. Open tibial fractures grade IIIC with massive soft tissue damage require combined orthopaedic, vascular and plastic–reconstructive procedures. Negative‐pressure wound therapy (NPWT), used in two consecutive cases with open fracture grade IIIC of the tibia diaphysis, healed extensive soft tissue defect with exposure of the bone. NPWT eventually allowed for wound closure by split skin graft within 21–25 days. Ilizarov external fixator combined with application of recombinant human bone morphogenetic protein‐7 at the site of delayed union enhanced definitive bone healing within 16–18 months.
Remedial Education with Incentivized Peer‐Tutoring: Evidence from Migrant Children Schools in China
Authors: Li Tao
Published: November 2012

This paper evaluates the impact of a remedial education program performed in two Chinese migrant children schools. The program used a conditional cash transfer contract to encourage peer tutors to help their underperforming classmates. Incentivized peer‐tutoring significantly improved the academic performance of the underperforming tutees over a semester. The impact persisted in the second semester when the intervention was removed. Our results suggest that nongovernment organizations and government agencies can increase their capacity of remedying education by incorporating incentivized peer‐tutoring into their existing merit‐based scholarship and conditional cash transfer programs.
Management and husbandry guidelines for Shoebills Balaeniceps rex in captivity
Authors: Muir A. , King C. E.
Published: November 2012

The Shoebill Balaeniceps rex is an uncommon species in zoological collections worldwide. Although a few Shoebills have lived quite long lives, most have not and successful breeding is only known to have occurred on two occasions. Available literature and responses from a husbandry questionnaire were used to compile husbandry guidelines. Questionnaire responses were obtained from 17 zoos (100% of holders worldwide at the time of writing). These guidelines form the basis of this paper.
Appreciating the ‘person’ in long‐term care
Authors: McCormack Brendan , Roberts Tonya , Meyer Julienne , Morgan Debra , Boscart Veronique
Published: November 2012

Background.  Internationally, approaches to the long‐term care of older people are changing. New models are being developed that aim to de‐institutionalise care settings, maximise opportunities for older people to participate in decision‐making and move from a predominant medical model of care to one that is community orientated.

Aims.  The aim of this study is to highlight similarities and differences between the different models that exist and explore the implications of these for the role of the registered nurse in long‐term care.

Methods.  We chose three models for review as these represent a range of views of person centredness, each having distinct roots and focus. The models chosen were as follows: (i) culture change, (ii) person‐centred practice and (iii) relationship‐centred care.

Results.  The review highlights two key issues – (i) the distinctiveness of different models and frameworks and (ii) different interpretations of ‘person’. Firstly, we identify a disconnection between espoused differences between models and frameworks and the reality of these differences. The evidence also identifies how some models and frameworks adopt a more inclusive conceptualisation of person and personhood and do not define personhood in relation to role (resident, nurse and family member).

Conclusions.  There is merit in the development of models and frameworks that try to make explicit the different dimensions of person centredness in long‐term care. However, the focus on the development of these, without sufficient attention being paid to evidence of best practices grounded in the concept of personhood, person‐centred care is in danger of losing its original humanistic emphasis. Further, models and frameworks need to take account of the personhood of all persons.

Implications for practice.  Registered nurses need to have an understanding of the concept of personhood to make sense of the various person‐centred practice frameworks that exist. Without this understanding, there is a danger that the essence of personhood may be lost in the zeal to implement particular models and frameworks.
Repellent efficacy and safety evaluation of IR3535 derivative against Aedes albopictus, Culex pipiens pallens and Aedes togoi
Authors: Park Sung Jin , Yu Mi hee , Kim Ji Eun , Park Min Ju , Lee In Seon , Lee Jihoon , Lee Jinho , Kim Bae Hwan , Lee Dong Kyu , Lee Sam Pin
Published: November 2012

The IR3535 derivative (LJH158), in which the ethyl ester of IR3535 was converted to methyl ester, was synthesized and studied as a new mosquito repellent. The repellent efficacy of LJH158 was compared with that of DEET against Aedes albopictus, Culex pipiens pallens and Aedes togoi. Also, the aromatic repellent tests were conducted with mixtures of repellents and the essential oils of cinnamon, which were obtained by supercritical fluid extraction. In addition, the safety issues of LJH158 were monitored using single oral dose safety methods and eye irritation, and skin irritation tests. The results of repellent efficacy in both biting and aromatic tests and safety tests demonstrate that LJH158 has high potential to be used as a new repellent or in combination with other repellents.
Insecticidal activity of recombinant baculovirus expressing both spider toxin isolated from Araneus ventricosus and Bacillus thuringiensis crystal protein fused to a viral polyhedrin
Authors: Jung Myung‐Pyo , Choi Jae Young , Tao Xue Ying , Jin Byung Rae , Je Yeon Ho , Park Hong‐Hyun
Published: November 2012

A novel recombinant Autographa californica nucleopolyhedrovirus (AcMNPV), ApPolh5‐3006AvTox2, co‐expressing two insecticidal toxins, one isolated from the spider Araneus ventricosus, and the other from Bacillus thuringiensis, was constructed to improve the insecticidal activity of AcMNPV. The recombinant virus was designed to express insect‐specific spider toxin, Av‐Tox2, under control of the early promoter from Cotesia plutellae bracovirus (CpBV). In addition, the B. thuringiensis cry1‐5 crystal protein gene was introduced into the genome of this recombinant virus by fusing it with the viral polyhedrin gene, thus creating a hybrid polyhedrin‐cry1‐5 gene under control of the polyhedrin gene promoter. Reverse transcription‐polymerase chain reaction (RT‐PCR) analysis revealed that both Av‐Tox2 and Polyhedrin‐Cry1‐5 fusion protein were successfully expressed in the infected cells. In addition, SDS‐PAGE revealed that Polyhedrin‐Cry1‐5 fusion protein expressed by recombinant viruses occluded the polyhedra. ApPolh5‐3006AvTox2 showed significantly reduced LD50 and ST50 values against both Plutella xylostella and Spodoptera exigua larvae. These results strongly suggested that coexpression of spider and B. thuringiensis insecticidal toxins could be successful in improving the insecticidal activity of baculoviruses.
The relationship between nurses’ oral hygiene and the mouth care of their patients
Authors: Ashkenazi Malka , Yaish Yaniv , Yitzhak Moran , Sarnat Haim , Rakocz Meir
Published: November 2012

To investigate the extent to which a relationship may exist between nurses’ own oral hygiene and their commitment and capability of following instructions for tooth brushing with conventional and triple‐headed toothbrushes, to cerebral palsy (CP) children. The study included 43 individuals with CP and their 44 nurses. A structured questionnaire was designed to assess I. Demographic characteristics of the nurses II. Nurses’ knowledge and maintenance of their own oral‐hygiene and that of their CP patients. Nurses’ ability to follow instruction for tooth‐brushing was evaluated and scored using the TB‐PS‐I/Ashkenazi index following the first brushing, as well as on a recall visit one month later. More nurses (72.7%) reported routine tooth‐brushing in the morning than in the evening (40.9%). Most nurses (73%) reported not flossing their teeth at all, and more than half reported visiting their dentist only when they suffer pain. A positive correlation was found between the nurses’ knowledge of preventive oral measures and their compliance with their own oral hygiene and with that of their CP patients. Similarly, a positive correlation was found between nurses’ receiving previous instruction for correct oral hygiene and their maintenance of their patients’ oral hygiene. Institutions for CP patients should disseminate information on oral hygiene to staff, as a means of increasing their maintenance of their patients’ oral health.
Different Physiological Reactions at Vegetative and Generative Stage of Development of Field Bean Plants Exposed to Flooding and Undergoing Recovery
Authors: Pociecha E.
Published: November 2012

Plants at various stages of growth are differentiated in their susceptibility to environmental stresses and possibility of regeneration during recovery period after cessation of stress. The role of antioxidative enzymes in the stabilisation of the physiological state of field bean plants was studied. Catalase, peroxidises activity, and hydrogen peroxide accumulation were determined after 1 and 7 days of flooding and after 1 and 7 days of recovery from flooding. The influence of flooding on plants growth was analysed on the basis of leaf area index (LAI), relative growth rate (RGR) and net assimilation rate (NAR). Changes in antioxidative enzymes caused by flooding applied at vegetative stage were reversible. In generative plants, antioxidative enzymes were activated to a greater extent during recovery period and in contrast to vegetative plants did not attain the control level after that period. The reduction in growth was greater when flooding stress was applied at vegetative stage. Vegetative plants regardless of the stabilisation of antioxidant system were not able to restore the physiological function to attain the optimal growth level after flooding. Probably other injuries caused by flooding had a dominant effect on enzymatic antioxidant changes during stress period.
Ditch the niche – is the niche a useful concept in ecology or species distribution modelling?
Authors: McInerny Greg J. , Etienne Rampal S.
Published: November 2012

In this first of three papers we examine the use of niche concepts in ecology and especially in species distribution modelling (SDM). This paper deliberately focuses on the lack of clarity found in the term ‘niche’. Because its meanings are so diverse, the term niche tends to create confusion and requires constant qualification. The literature houses many idiosyncratic ideas of what the niche is, but few examples where niche is more explanatory than the terminologies of population and community ecology or the statistical methods used to implement SDM analyses. In many cases the original (and inspirational) concepts are not directly applicable to our modern applications (e.g. set theory). There are some conceptual limitations found in individual definitions of niche (e.g. the fundamental niche concept), so it is perhaps understandable why more neutral terminology is becoming popular in SDM. An examination of the literature reveals a wide range of uncritical use of niche terminology. Our findings in this paper do not necessarily support the position of niche as a universally useful concept.
Transport of the areca nut alkaloid arecaidine by the human proton-coupled amino acid transporter 1 (hPAT1)
Authors: Voigt Valerie , Laug Linda , Zebisch Katja , Thondorf Iris , Markwardt Fritz , Brandsch Matthias
Published: November 2012

Objectives

The pyridine alkaloid arecaidine is an ingredient of areca nut preparations. It is responsible for many physiological effects observed during areca nut chewing. However, the mechanism underlying its oral bioavailability has not yet been studied. We investigated whether the H+-coupled amino acid transporter 1 (PAT1, SLC36A1), which is expressed in the intestinal epithelium, accepts arecaidine, arecoline, isoguvacine and other derivatives as substrates.

Methods

Inhibition of l-[3H]proline uptake by arecaidine and derivatives was determined in Caco-2 cells expressing hPAT1 constitutively and in HeLa cells transiently transfected with hPAT1-cDNA. Transmembrane transport of arecaidine and derivatives was measured electrophysiologically in Xenopus laevis oocytes.

Key findings

Arecaidine, guvacine and isoguvacine but not arecoline strongly inhibited the uptake of l-[3H]proline into Caco-2 cells. Kinetic analyses revealed the competitive manner of l-proline uptake inhibition by arecaidine. In HeLa cells transfected with hPAT1-cDNA an affinity constant of 3.8 mm was obtained for arecaidine. Electrophysiological measurements at hPAT1-expressing X. laevis oocytes demonstrated that arecaidine, guvacine and isoguvacine are transported by hPAT1 in an electrogenic manner.

Conclusion

We conclude that hPAT1 transports arecaidine, guvacine and isoguvacine across the apical membrane of enterocytes and that hPAT1 might be responsible for the intestinal absorption of these drug candidates.
Quantitative analysis of the intra‐ and inter‐subject variability of the whole salivary proteome
Authors: Jehmlich N. , Dinh K. H. D. , Gesell‐Salazar M. , Hammer E. , Steil L. , Dhople V. M. , Schurmann C. , Holtfreter B. , Kocher T. , Völker U.
Published: November 2012

Background and Objective

Interest in human saliva is increasing for disease‐specific biomarker discovery studies. However, protein composition of whole saliva can grossly vary with physiological and environmental factors over time and it comprises human as well as bacterial proteins.

Material and Methods

We compared intra‐ and inter‐subject variabilities using complementary gel‐based (two‐dimensional difference gel electrophoresis, 2‐D DIGE) and gel‐free (liquid chromatography tandem mass spectrometry, LC‐MS/MS) proteomics profiling of saliva. Unstimulated whole saliva of four subjects was examined at three different time‐points (08.00 h, 12.00 h and 17.00 h) and variability of the saliva proteome was analyzed on two successive days by LC‐MS/MS.

Results

In the 2‐D DIGE experiment, the median coefficient of variation (CV) for intra‐subject variability was significantly lower (CV of 0.39) than that for inter‐subject variability (CV of 0.57; CV of technical replicates 0.17). LC‐MS/MS data confirmed the significantly lower variation within subjects over time (CV of 0.37) than the inter‐subject variability (CV of 0.53; CV of technical replicates 0.11), and that the inter‐subject variability was not time‐dependent.

Conclusion

Both techniques revealed similar trends of variations on technical, intra‐ and inter‐subject level but provided peptide and protein focused information and should thus be used as complementary approaches. The data presented indicate that 2‐D DIGE as well as LC‐MS/MS approaches are suitable for biomarker screening in saliva.
Strengthening Ambition for Climate Mitigation: The Role of the Montreal Protocol in Reducing Short‐lived Climate Pollutants
Authors: Zaelke Durwood , Andersen Stephen O. , Borgford‐Parnell Nathan
Published: November 2012

The level of ambition of the public and policy makers to protect the climate is currently far too low to slow the accelerating pace of climate impacts. Ambition can be strengthened using strategies that disaggregate the overall climate problem into manageable pieces, borrow existing laws and institutions to take fast action following a ‘start and strengthen’ approach. This is illustrated by the strategy to phase down the production and consumption of high global warming potential hydrofluorocarbons under the Montreal Protocol. Such an approach could cut the rate of global warming in half for the next several decades, and even more in the Arctic and other climate vulnerable regions. This can provide fast success and build the sense of urgent optimism needed to raise ambition to do more to address carbon dioxide emissions – the single largest contributor to climate change.
All Hands on Deck! Mobilizing Climate Change Action beyond the UNFCCC
Authors: Moncel Remi , van Asselt Harro
Published: November 2012

While taking notable incremental steps forward, Parties to the United Nations Framework Convention on Climate Change (UNFCCC) have so far, in aggregate, been unable to scale up their ambition to mitigate climate change so as to hold a rise in global average temperature below 2° Celsius above pre‐industrial levels. In this introduction to the special issue, it is posited that the UNFCCC has played and should continue to play an essential role in instigating and coordinating a global response to climate change. However, in the face of continuing difficulty in stabilizing the global climate at safe levels, it is argued here that the UNFCCC is by no means alone in addressing this challenge and that wider international cooperation is possible in a way that complements the international climate negotiations. This article shows how a variety of international institutions outside of the UNFCCC have sought – albeit with modest results to date – to address climate change, and indicates how these institutions could be enhanced to deliver greater climate change mitigation benefits. It then illustrates how these institutions may interact with the UNFCCC process, and examines the role of the UNFCCC in ensuring that the various institutions work in a complementary fashion.
Effects of nutritional supplementation combined with conventional pulmonary rehabilitation in muscle‐wasted chronic obstructive pulmonary disease: A prospective, randomized and controlled study
Authors: Gurgun Alev , Deniz Sami , Argın Mehmet , Karapolat Hale
Published: November 2012

Background and objective

Nutritional depletion in chronic obstructive pulmonary disease (COPD) adversely affects health status and mortality. We aimed to evaluate the effects of nutritional supplementation (NS) with pulmonary rehabilitation (PR) on body composition, mid‐thigh cross‐sectional area (CSA), dyspnoea, exercise capacity, health‐related quality of life, anxiety and depression in advanced COPD patients.

Methods

Forty‐six patients were randomized to PR and nutritional support (PRNS), PR or the control group. Dyspnoea was measured with Medical Research Council and BORG scales. Exercise capacity was measured through 6‐min walk test and shuttle tests; health‐related quality of life was assessed with St. George's Respiratory Questionnaire. Psychological status was measured with Hospital Anxiety and Depression Scale. Body weight and body mass indexes (BMI) were also evaluated. Fat‐free mass was measured through bioelectrical impedance analyser. The CSA of quadriceps was calculated in mid‐level of the thigh with magnetic resonance imaging.

Results

Dyspnoea and total scores of St. George's Respiratory Questionnaire improved in both groups (P < 0.05). Six‐minute walk test and incremental shuttle walk test distances in PRNS and PR patients increased significantly as (62.6 ± 42.4 m, 43.3 ± 59.2 m, both P = 0.001; and 63.3 ± 70.1 m and 69.3 ± 69.7 m, both P = 0.001). Although anxiety improved in both groups (P < 0.05), there was no change in depression. Body weight, BMI and fat‐free mass index (FFMI) (1.1 ± 0.9 kg, 0.2 ± 1.4 kg/m2 and 0.6 ± 0.5 kg/m2, P < 0.05) in PRNS, whereas body weight and FFMI (0.6 ± 0.7 kg, 0.1 ± 0.6 kg/m2 P < 0.05) increased in PR after the intervention. There was a significant increase in mid‐thigh CSA (2.5 ± 4.1 cm2) only in PRNS (P = 0.04).

Conclusion

The combination of NS with PR resulted in improvements particularly in lean body mass and mid‐thigh CSA. This study suggests combining NS with PR in reversing weight loss and muscle wasting in COPD.
Biogenesis of photosynthetic complexes in the chloroplast of Chlamydomonas reinhardtii requires ARSA1, a homolog of prokaryotic arsenite transporter and eukaryotic TRC40 for guided entry of tail‐anchored proteins
Authors: Formighieri Cinzia , Cazzaniga Stefano , Kuras Richard , Bassi Roberto
Published: November 2012

as1, for antenna size mutant 1, was obtained by insertion mutagenesis of the unicellular green alga Chlamydomonas reinhardtii. This strain has a low chlorophyll content, 8% with respect to the wild type, and displays a general reduction in thylakoid polypeptides. The mutant was found to carry an insertion into a homologous gene, prokaryotic arsenite transporter (ARSA), whose yeast and mammal counterparts were found to be involved in the targeting of tail‐anchored (TA) proteins to cytosol‐exposed membranes, essential for several cellular functions. Here we present the characterization in a photosynthetic organism of an insertion mutant in an ARSA‐homolog gene. The ARSA1 protein was found to be localized in the cytosol, and yet its absence in as1 leads to a small chloroplast and a strongly decreased chlorophyll content per cell. ARSA1 appears to be required for optimal biogenesis of photosynthetic complexes because of its involvement in the accumulation of TOC34, an essential component of the outer chloroplast membrane translocon (TOC) complex, which, in turn, catalyzes the import of nucleus‐encoded precursor polypeptides into the chloroplast. Remarkably, the effect of the mutation appears to be restricted to biogenesis of chlorophyll‐binding polypeptides and is not compensated by the other ARSA homolog encoded by the C. reinhardtii genome, implying a non‐redundant function.
On–off asymmetries in oxygen consumption kinetics of single Xenopus laevis skeletal muscle fibres suggest higher‐order control
Authors: Wüst Rob C.I. , van der Laarse Willem J. , Rossiter Harry B.
Published: November 2012

Key points

Skeletal muscles increase oxygen consumption to produce energy during exercise; however, the processes controlling the rate of adaptation (its kinetics) at exercise onset and offset are not well understood.

Here we measure kinetics in single frog skeletal muscle fibres using a unique experimental system that allows features of intracellular control mechanisms to be elucidated.

We show for the first time that at contractions onset skeletal muscle kinetics are best described by a biphasic ‘activation’ and ‘exponential’ profile, whereas at cessation recovers with a single smooth exponential.

Additionally these features were dependent on oxidative capacity and the intensity of stimulated contractions.

These data show that the intracellular processes that activate oxidative energy provision at the onset of contractions are far more complex than previously suggested.

Abstract  The mechanisms controlling skeletal muscle oxygen consumption () during exercise are not well understood. We determined whether first‐order control could explain kinetics at contractions onset () and cessation () in single skeletal muscle fibres differing in oxidative capacity, and across stimulation intensities up to . Xenopus laevis fibres (n= 21) were suspended in a sealed chamber with a fast response electrode to measure every second before, during and after stimulated isometric contractions. A first‐order model did not well characterise on‐transient kinetics. Including a time delay (TD) in the model provided a significantly improved characterisation than a first‐order fit without TD (F‐ratio; P < 0.05), and revealed separate ‘activation’ and ‘exponential’ phases in 15/21 fibres contracting at (mean ± SD TD: 14 ± 3 s). On‐transient kinetics () was weakly and linearly related to (R2= 0.271, P= 0.015). Off‐transient kinetics, however, were first‐order, and was greater in low‐oxidative ( < 0.05 nmol mm−3 s−1) than high‐oxidative fibres ( > 0.10 nmol mm−3 s−1; 170 ± 70 vs. 29 ± 6 s, P < 0.001). was proportional to (R2= 0.727, P < 0.001), unlike in the on‐transient. The calculated oxygen deficit was larger (P < 0.05) than the post‐contraction volume of consumed oxygen at all intensities except . These data show a clear dissociation between the kinetic control of at the onset and cessation of contractions and across stimulation intensities. More complex models are therefore required to understand the activation of mitochondrial respiration in skeletal muscle at the start of exercise.
Understanding the Twin Scroll Turbine: Flow Similarity
Authors: Brinkert Nils , Sumser Siegfried , Weber Siegfried , Fieweger Klaus , Schulz Achmed , Bauer Hans-Jörg
Published: November 2012

The current study investigates the flow conditions of a twin scroll asymmetric turbine. This is motivated by the operating conditions of the turbine at a heavy-duty reciprocating internal combustion engine with exhaust gas recirculation. The flow conditions of the turbine at the engine can be described best with the turbine scroll interaction map. Standard hot gas measurements of a turbocharger turbine are presented and discussed. Due to the strong interaction of the turbine scrolls, further hot gas measurements are performed at partial admission conditions. The turbine inlet conditions are analyzed experimentally, in order to characterize the turbine performance. The turbine scroll pressure ratio is varied, leading to unequal twin turbine admission conditions. The flow behavior is analyzed regarding its ability for further extrapolation. Beyond scroll pressure ratio variations, unequal temperature admission conditions were studied. A way of characterizing the representative turbine inlet temperature, regarding the reduced turbine speed, is presented. The different scroll parameter ratios are evaluated regarding their capability of describing flow similarity under different unequal turbine admission conditions. In this content, turbine scroll Mach number ratio, velocity ratio and mass flow ratio are assessed. Furthermore, a generic representation of the turbine flow conditions at the engine is presented, based on standard turbine performance maps.
URANS Calculations for Smooth Circular Cylinder Flow in a Wide Range of Reynolds Numbers: Solution Verification and Validation
Authors: Rosetti Guilherme F. , Vaz Guilherme , Fujarra André L. C.
Published: November 2012

The flow around circular smooth fixed cylinder in a large range of Reynolds numbers is considered in this paper. In order to investigate this canonical case, we perform CFD calculations and apply verification & validation (V&V) procedures to draw conclusions regarding numerical error and, afterwards, assess the modeling errors and capabilities of this (U)RANS method to solve the problem. Eight Reynolds numbers between Re = 10 and Re=5×105 will be presented with, at least, four geometrically similar grids and five discretization in time for each case (when unsteady), together with strict control of iterative and round-off errors, allowing a consistent verification analysis with uncertainty estimation. Two-dimensional RANS, steady or unsteady, laminar or turbulent calculations are performed. The original 1994 k-ω SST turbulence model by Menter is used to model turbulence. The validation procedure is performed by comparing the numerical results with an extensive set of experimental results compiled from the literature.
Postconsumer Plastic Waste Over Post-Use Cracking Catalysts for Producing Hydrocarbon Fuels
Authors: Lin Yeuh-Hui , Wei Ta-Tung , Yang Mu-Hoe , Lee Sheau-Long
Published: November 2012

The recycling of plastic waste is important both in the conservation of resources and the environment. A plastic waste (polyethylene(PE)/polypropylene(PP)/polystyrene(PS)/polyvinyl chloride(PVC)) was pyrolyzed over a series of post-use fluid catalytic cracking (FCC) catalysts using a fluidizing reaction system similar to the FCC process operating isothermally at ambient pressure. Experiments carried out with these catalysts gave good yields of valuable hydrocarbons with differing selectivity in the final products dependent on reaction conditions. A model based on kinetic considerations associated with chemical reactions and catalyst deactivation in the catalytic degradation of plastics has been developed. Greater product selectivity was observed with a hybrid catalyst (SAHA/CAT-R1) of amorphous silica-aluminas (SAHA) and a recycle FCC catalyst with regeneration (CAT-R1) with more than 68.6 wt. % olefins products. It is demonstrated that the catalytic degradation of postconsumer plastics over these recycled catalysts using fluidizing cracking reactions was shown to be a useful method for the production of potentially valuable hydrocarbons.
Modeling and Analysis of Drillstring Vibration in Riserless Environment
Authors: Samuel Robello
Published: November 2012

Riserless drilling poses numerous operational challenges that adversely affect the efficiency of the drilling process. These challenges include increased torque and drag, buckling, increased vibration, poor hole cleaning, tubular failures, poor cement jobs, and associated problems during tripping operations. These challenges are closely associated with complex bottomhole assemblies (BHAs) and the vibration of the drillstring when the topholes are drilled directionally. Current methods lack proper modeling to predict drillstring vibration. This paper presents and validates a modified model to predict severe damaging vibrations, analysis techniques, and guidelines to avoid the vibration damage to BHAs and their associated downhole tools in the riserless highly deviated wells. The dynamic analysis model is based on forced frequency response (FFR) to solve for resonant frequencies. In addition, a mathematical formulation includes viscous, axial, torsional, and structural damping mechanisms. With careful consideration of input parameters and judicious analysis of the results, the author demonstrates that drillstring vibration can be avoided by determining the 3D vibrational response at selected excitations that are likely to cause them. The analysis also provides an estimate of relative bending stresses, shear forces, and lateral displacements for the assembly used. Based on the study, severe vibrations causing potentially damaging operating conditions were avoided, which posed a major problem in the nearby wells. The study indicates that the results are influenced by various parameters, including depth of the mud line, offset of the wellhead from the rig center, wellbore inclination, curvature, wellbore torsion, and angle of entry into the wellhead. This study compares simulated predictions with actual well data and describes the applicability of the model. Simple guidelines are provided to estimate the operating range of the drilling parameter to mitigate and avoid downhole tool failures.
Experimental Investigation by Speckle Interferometry of Solder Joint Failure Under Thermomechanical Load Aggravated by Boundary Conditions at Board Level
Authors: Borza D. N. , Nistea I. T.
Published: November 2012

Reliability of electronic assemblies at board level and solder joint integrity depend upon the stress applied to the assembly. The stress is often of thermomechanical or of vibrational nature. In both cases, the behavior of the assembly is strongly influenced by the mechanical boundary conditions created by the printed circuit board (PCB) to casing fasteners. In many previously published papers, the conditions imposed to the fasteners are mostly aiming at an increase of the fundamental frequency and a decrease of static or dynamic displacement values characterizing the deformation. These conditions aim at reducing the fatigue in different parts of these assemblies. In the photomechanics laboratory of INSA Rouen, the origins of solder joint failure have been investigated by means of full-field measurements of the flexure deformation induced by vibrations or by forced thermal convection. The measurements were done both at a global level for the whole printed circuit board assembly (PCBA) and at a local level at the solder joints where failure was reported. The experimental technique used was phase-stepped laser speckle interferometry. This technique has a submicrometer sensitivity with respect to out-of-plane deformations induced by bending and its use is completely nonintrusive. Some of the results were comforted by comparison with a numerical finite elements model. The experimental results are presented either as time-average holographic fringe patterns, as in the case of vibrations, or as wrapped phase patterns, as in the case of deformation under thermomechanical stress. Both types of fringe patterns may be processed so as to obtain the explicit out-of-plane static deformation (or vibration amplitude) maps. Experimental results show that the direct cause of solder joint failure may be a high local PCB curvature produced by a supplementary fastening screw intended to reduce displacements and increase fundamental frequency. The curvature is directly responsible for tensile stress appearing in the leads of a large quad flat pack (QFP) component and for shear in the corresponding solder joints. The general principle of increasing the fundamental frequency and decreasing the static or dynamic displacement values has to be checked against the consequences on the PCB curvature near large electronic devices having high stiffness.
Dual-Frequency Severe Slugging in Horizontal Pipeline-Riser Systems
Authors: Malekzadeh Reza , Mudde Robert F. , Henkes Ruud A. W. M.
Published: November 2012

A new type of severe slugging is found that can occur in two-phase flow of gas and liquid in pipeline-riser systems. This instability, which will be referred to as dual-frequency severe slugging (DFSS), generates a different class of flow oscillations compared to the classical severe slugging cycle, having a dominant single frequency that is commonly found in a pipe downward inclined by a few degrees from the horizontal connected to a vertical riser. The DFSS flow pattern was found in laboratory experiments carried out in a 100 m long, 50.8 mm diameter horizontal pipeline followed by a 15 m high, 50.8 mm diameter vertical riser operating at atmospheric end pressure. The experimental facility also included a 400 liter gas buffer vessel, placed upstream of the pipeline, to obtain extra pipeline compressibility. Air and water were used as the experimental fluids. At constant inflow conditions, we observed a type of severe slugging exhibiting a dual-frequency behavior. The relatively high-frequency fluctuations, which are in the order of 0.01 Hz, are related to the classical severe slugging cycle or to an unstable oscillatory process. The relatively low-frequency fluctuations, which are in the order of 0.001 Hz, are associated with the gradual cyclic transition of the system between two metastable states, i.e., severe slugging and unstable oscillations. Numerical simulations were performed using OLGA, a one-dimensional two-fluid flow model. The numerical model predicts the relatively low-frequency fluctuations associated with the DFSS flow regime. The laboratory experiments and the numerical simulations showed that the evolution of the DFSS is proportional to the length of the pipeline.
Design for Assembly Guidelines for High-Performance Compliant Mechanisms
Authors: Gandhi Prasanna , Sonawale Kaustubh , Soni Vaibhav , Patanwala Naved , Bansode Arvind
Published: November 2012

Compliant mechanisms with ultrahigh precision motion are being increasingly used for several applications including micromeasurement, micro/nanomanipulation, microfabrication, and so on. Flexure linkages offer inherent advantages of being frictionless, highly repeatable, and having great design flexibility. Monolithic fabrication of these mechanisms limits the use of multiple materials for optimized design and is expensive or infeasible especially for three-dimensional mechanisms. An alternative method of assembling components of a compliant mechanism is considered in this paper and design for assembly guidelines are put forth. It is found that if each of the connections of a compliant mechanism is constrained exactly using two pins as per the traditional practice, internal stresses are generated in the links and their warping does not allow the desired operation of the mechanism. The proposed guidelines, which are based on Grubler’s criteria, include a simple formulation to determine number of locating pins to be used in the entire assembly. Further, these guidelines also determine the locations of these pins. Several compliant mechanisms were fabricated and assembled using these guidelines and were found to be working satisfactorily.
T-Stresses for Edge Cracks and Vanishing Ligaments
Authors: Dempsey John P.
Published: November 2012

An edge-cracked half-plane 0 < x < A and a half-plane x > 0 with a semi-infinite crack x > a perpendicular to the edge are examined in this paper. Uniform crack-face loading is thoroughly examined, with a thorough exposition of the Koiter Wiener–Hopf approach (Koiter, 1956, “On the Flexural Rigidity of a Beam Weakened by Transverse Saw Cuts,” Proc. Royal Neth. Acad. of Sciences, B59, pp. 354–374); an analytical expression for the corresponding T-stress is obtained. For the additional cases of (i) nonuniform edge-crack crack-face loading σ(x/A)k (ℜ(k)>-1), (ii) concentrated loading at the edge-crack crack mouth, the Wiener–Hopf solutions and analytical T-stress expressions are provided, and tables of T-stress results for σ(x/A)k and σ(1-x/A)k are presented. A Green's function for the edge-crack T-stress is developed. The differing developments made by Koiter (1956, “On the Flexural Rigidity of a Beam Weakened by Transverse Saw Cuts,” Proc. Royal Neth. Acad. of Sciences, B59, pp. 354–374, Wigglesworth (1957, “Stress Distribution in a Notched Plate,” Mathematika, 4, pp. 76–96), and Stallybrass (1970, “A Crack Perpendicular to an Elastic Half-Plane,” Int. J. Eng. Sci., 8, pp. 351–362) for the case of an edge-cracked half-plane are enhanced by deducing a quantitative relationship between the three different Wiener–Hopf type factorizations. An analytical universal T-stress expression for edge-cracks is derived. Finally, the case of a vanishing uncracked ligament in a half-plane is examined, and the associated Wiener–Hopf solution and analytical T-stress expression are again provided. Several limiting cases are examined.