bluuebunny/crossref_metadata_2025 huggingface dataset:
Evaluation of humoral immune response to donor HLA after implantation of cellularized versus decellularized human heart valve allografts
Authors: Kneib C. , von Glehn C. Q. C. , Costa F. D. A. , Costa M. T. B. A. , Susin M. F.
Published: May 2012

We have evaluated the development of antibodies in response to donor allograft valve implant in patients who received cellularized and decellularized allografts and determined possible immunogenic epitopes considered responsible for antibodies reactivity. Serum samples from all recipients who received cellularized allografts or decellularized allografts were collected before valve replacement and at 5, 10, 30 and 90 days post‐operatively and frozen until required. Tests were performed using the Luminex‐based single human leukocyte antigen (HLA)‐A, ‐B, ‐C and HLA‐DR, ‐DQ antigen microsphere assay. To determine possible immunogenic epitopes, we used the HLAMatchmaker (HLAMM) software if applicable. Decellularized grafts elicited lower levels of anti‐HLA class I and II antibody formation after implantation than cellularized allografts. All patients from cellularized group presented donor‐specific antibodies class I and II within 3 months of observation period. In HLAMM analysis, the cellularized group had significantly higher numbers of immunogenic epitopes than decellularized group for both class I and II (p: 0.002 – cl I / p: 0.009 – cl II / p: 0.004 – cl I and II). Our findings demonstrate that the anti‐HLA antibodies detected in the cellularized group were against donor HLA possible immunogenic epitopes and that in the decellularized group the anti‐HLA antibodies were not against donor HLA possible immunogenic epitopes. These findings lead us to suggest that choosing sodium dodecyl sulfate decellularization process is the best alternative to decrease the immunogenicity of allograft valve transplant.
Characterization of the novel HLA‐DPB1*139:01 allele identified by sequence‐based typing in a Chinese Han individual
Authors: Wang D. , Xu Y. , He L.‐M. , Deng Z.
Published: May 2012

Compared with HLA‐DPB1*24:01, DPB1*139:01 has two changes at nucleotide positions 280 (A to C) and 338 (G to T).
Colonoscopic enema as rescue for inadequate bowel preparation before colonoscopy: a prospective, observational study
Authors: Horiuchi A. , Nakayama Y. , Kajiyama M. , Kato N. , Kamijima T. , Ichise Y. , Tanaka N.
Published: May 2012

Aim  Colonoscopy may need to be rescheduled because of inadequate bowel preparation. We evaluated the effectiveness of colonoscopic enema as rescue for an inadequate 1‐day bowel preparation before colonoscopy.

Method  Patients referred for afternoon colonoscopy were prospectively enrolled in the study during a 1‐year period. Patients took bowel preparation (polyethylene glycol) solution on the morning of the endoscopy. If during colonoscopy the bowel preparation was poor, an enema of polyethylene glycol solution (500 ml) was instilled into the colon at the level of the hepatic flexure via the biopsy channel of the colonoscope which was then removed. The patient was allowed to recover from the propofol sedation and used the bathroom to evacuate the enema. The colonoscope was then introduced and the examination continued.

Results  Of 504 patients undergoing colonoscopy, 26 (4.9%) received an enema. The median age was 59 (29–79) years and 19 (73%) were female. A subsequent successful colonoscopy was achieved in 25/26 (96%). There were no complications. The mean time spent for the entire colonoscopy from the initial preparation to the end of the examination including the enema was 7.6 ± 1.1 h (5.4 h preparation, 0.2 h first colonoscopy + enema, 0.66 h waiting in the lavatory, 0.33 h second colonoscopy and 1 h for recovery).

Conclusion  Colonoscopic enema was highly successful as rescue for patients with inadequate bowel preparation and avoided postponement of the procedure.
Serum 25‐hydroxyvitamin D predicts severity and prognosis in stroke patients
Authors: Daubail B. , Jacquin A. , Guilland J.‐C. , Hervieu M. , Osseby G.‐V. , Rouaud O. , Giroud M. , Béjot Y.
Published: May 2012

Background and purpose

We aimed to evaluate the association between 25‐hydroxyvitamin D (25(OH)D) levels and both clinical severity at admission and outcome at discharge in stroke patients.

Methods

From February 2010 to December 2010, consecutive stroke patients admitted to the Department of Neurology of Dijon, France, were identified. Clinical information was collected. Serum concentration of 25(OH)D was measured at baseline. Stroke severity was assessed at admission using the NIHSS score. Functional impairment was evaluated at discharge using the modified Rankin scale (m‐Rankin). Multivariate analyses were performed using logistic regression models.

Results

Of the 386 recorded patients, serum 25(OH)D levels were obtained in 382 (median value = 35.1 nM; IQR = 21–57.8). At admission, 208 patients had a NIHSS ≤5, with a higher mean 25(OH)D level than that observed in patients with moderate‐to‐high severity (45.9 vs. 38.6 nM, P < 0.001). In multivariate analyses, a 25(OH)D level in the lowest tertile (<25.7 nM) was a predictor of a NIHSS ≥6 (OR = 1.67; 95% CI = 1.05–2.68; P = 0.03). The mean 25(OH)D level was lower in patients with moderate‐to‐severe handicap at discharge (m‐Rankin 3–6) than in patients with no or mild handicap (35.0 vs. 47.5 nM, P < 0.001). In multivariate analyses, the lowest tertile of 25(OH)D level (<25.7 nM) was associated with a higher risk of moderate‐to‐severe handicap (OR = 2.06; 95% CI = 1.06–3.94; P = 0.03).

Conclusion

A low serum 25(OH)D level is a predictor of both severity at admission and poor early functional outcome in stroke patients. The underlying mechanisms of these associations remain to be investigated.
Alternating verbal fluency performance following bilateral subthalamic nucleus deep brain stimulation for Parkinson's disease
Authors: Marshall D. F. , Strutt A. M. , Williams A. E. , Simpson R. K. , Jankovic J. , York M. K.
Published: May 2012

Background and purpose

Despite common occurrences of verbal fluency declines following bilateral subthalamic nucleus deep brain stimulation (STN‐DBS) for the treatment of Parkinson's disease (PD), alternating fluency measures using cued and uncued paradigms have not been evaluated.

Methods

Twenty‐three STN‐DBS patients were compared with 20 non‐surgical PD patients on a comprehensive neuropsychological assessment, including cued and uncued intradimensional (phonemic/phonemic and semantic/semantic) and extradimensional (phonemic/semantic) alternating fluency measures at baseline and 6‐month follow‐up.

Results

STN‐DBS patients demonstrated a greater decline on the cued phonemic/phonemic fluency and the uncued phonemic/semantic fluency tasks compared to the PD patients. For STN‐DBS patients, verbal learning and information processing speed accounted for a significant proportion of the variance in declines in alternating phonemic/phonemic and phonemic/semantic fluency scores, respectively, whilst only naming was related to uncued phonemic/semantic performance for the PD patients. Both groups were aided by cueing for the extradimensional task at baseline and follow‐up, and the PD patients were also aided by cueing for the phonemic/phonemic task on follow‐up.

Conclusions

These findings suggest that changes in alternating fluency are not related to disease progression alone as STN‐DBS patients demonstrated greater declines over time than the PD patients, and this change was related to declines in information processing speed.
The difficulty of using species distribution modelling for the conservation of refugee species – the example of European bison
Authors: Cromsigt Joris P. G. M. , Kerley Graham I. H. , Kowalczyk Rafał
Published: May 2012

Refugee species have been confined to suboptimal habitat through historic anthropogenic factors. If this is unknown, management might actively conserve these species in suboptimal habitat assuming it represents optimal habitat. Similarly, species distribution modelling (SDM) might misguide conservation management of refugee species by only using presence data from suboptimal habitats. We illustrate this by commenting on a recentSDMforEuropean bison that reconstructed the historic distribution of the species. We challenge the interpretation of this model by suggesting an alternative historic biogeography based on the refugee species concept. We argue that, in the case of refugee species, historic reconstructions usingSDMcannot be used as a template for conservation management. Rather, experimental re‐introduction programmes should provide us with population performance and life history data from a range of suboptimal to optimal habitats. Such data could be used in mechanistic niche modelling to predict potential distribution of refugee species.
Radiographic lymphangiographyin the dog using iodized oil
Authors: Mayer M. N. , Silver T. I. , Lowe C. K. , Anthony J. M.
Published: May 2012

The objective of this study was to develop a clinically applicable technique to visualize the medial retropharyngeal, superficial cervical, axillary, superficial inguinal and medial iliac lymph nodes on radiographs. Direct and indirect lymphangiographic methods using iodized oil were repeated for a minimum of five times at eight different locations to enhance the various lymph nodes, using 16 healthy research dogs. Direct lymphangiography, although more invasive than indirect lymphangiography, resulted in uniform contrast uptake by an increased number of nodes and increased enhancement of the lymphatic vasculature, and is recommended for imaging the medial iliac and superficial cervical lymph nodes. Side effects were more frequent after indirect lymphangiography (10/20 injection sites) than after direct lymphangiography (3/16 injection sites). The small size of afferent lymphatic vessels did not allow use of direct lymphangiography for the medial retropharyngeal, axillary and superficial inguinal lymph nodes; however, indirect techniques allowed adequate visualization of these nodes.
VARIATION IN THE ABUNDANCE OF SYNECHOCOCCUS SP. CC9311 NARB MRNA RELATIVE TO CHANGES IN LIGHT, NITROGEN GROWTH CONDITIONS AND NITRATE ASSIMILATION1
Authors: Paerl Ryan W. , Tozzi Sasha , Kolber Zbigniew S. , Zehr Jonathan P.
Published: May 2012

Synechococcus‐ and Prochlorococcus‐specific narB genes that encode for an assimilatory nitrate reductase are found in coastal to open‐ocean waters. However, it remains uncertain if these picocyanobacteria assimilate nitrate in situ. This unknown can potentially be addressed by examining narB mRNA from the environment, but this requires a better understanding of the influence of environmental factors on narB gene transcription. In laboratory experiments with Synechococcus sp. CC9311 cultures exposed to diel light fluctuations and grown on nitrate or ammonium, there was periodic change in narB transcript abundance. This periodicity was broken in cultures subjected to a doubling of irradiance (40–80 μmol photons · m−2 · s−1) during the mid‐light period. Therefore, the irradiance level, not circadian rhythm, was the dominant factor controlling narB transcription. In nitrate‐grown cultures, diel change in narB transcript abundance and nitrate assimilation rate did not correlate; suggesting narB mRNA levels better indicate nitrate assimilation activity than assimilation rate. Growth history also affected narB transcription, as changes in narB mRNA levels in nitrogen‐deprived CC9311 cultures following nitrate amendment were distinct from cultures grown solely on nitrate. Environmental sampling for narB transcripts should consider time, irradiance, and the growth status of cells to ecologically interpret narB transcript abundances.
MORPHOLOGY AND MOLECULAR PHYLOGENY OF ANKISTRODINIUM GEN. NOV. (DINOPHYCEAE), A NEW GENUS OF MARINE SAND‐DWELLING DINOFLAGELLATES FORMERLY CLASSIFIED WITHIN AMPHIDINIUM1
Authors: Hoppenrath Mona , Murray Shauna , Sparmann Sarah F. , Leander Brian S.
Published: May 2012

The classical athecate dinoflagellate genera (Amphidinium, Gymnodinium, Gyrodinium) have long been recognized to be polyphyletic. Amphidinium sensu lato is the most diverse of all marine benthic dinoflagellate genera; however, following the redefinition of this genus ∼100 species remain now of uncertain or unknown generic affiliation. In an effort to improve our taxonomic and phylogenetic understanding of one of these species, namely Amphidinium semilunatum, we re‐investigated organisms from several distant sites around the world using light and scanning electron microscopy and molecular phylogenetic methods. Our results enabled us to describe this species within a new heterotrophic genus, Ankistrodinium. Cells of A. semilunatum were strongly laterally flattened, rounded‐quadrangular to oval in lateral view, and possessed a small asymmetrical epicone. The sulcus was wide and characteristically deeply incised on the hypocone running around the antapex and reaching the dorsal side. The straight acrobase with hook‐shaped end started at the sulcal extension and continued onto the epicone. The molecular phylogenetic results clearly showed that A. semilunatum is a distinct taxon and is only distantly related to species within the genus Amphidinium sensu stricto. The nearest sister group to Ankistrodinium could not be reliably determined.
Bidirectional Relations Between Authoritative Parenting and Adolescents’ Prosocial Behaviors
Authors: Padilla‐Walker Laura M. , Carlo Gustavo , Christensen Katherine J. , Yorgason Jeremy B.
Published: May 2012

This study examined the bidirectional relations between authoritative parenting and adolescents’ prosocial behavior over a 1‐year time period. Data were taken from Time 2 and 3 of the Flourishing Families Project, and included reports from 319 two‐parent families with an adolescent child (M age of child at Time 2 = 12.34, SD = 1.06, 52% girls). Cross‐lag analyses supported bidirectional relations between parenting and prosocial behavior with particular emphasis on the role of the adolescents’ prosocial behavior on subsequent parenting. Results also varied as a function of the reporter. Discussion focuses on the implications for understanding the multifaceted nature of prosocial development in adolescence.
A systematic review of psychological interventions for excessive alcohol consumption among people with psychotic disorders
Authors: Baker A. L. , Hiles S. A. , Thornton L. K. , Hides L. , Lubman D. I.
Published: May 2012

Baker AL, Hiles SA, Thornton LK, Hides L, Lubman DI. A systematic review of psychological interventions for excessive alcohol consumption among people with psychotic disorders.

Objective:  Excessive alcohol consumption is common among people with psychotic disorders. While there is an extensive literature on the efficacy of psychological treatments for excessive drinking, few studies have examined interventions addressing this issue among people with psychotic disorders.

Method:  Systematic searches in PubMed and PsycINFO were conducted to identify randomized controlled trials comparing manual‐guided psychological interventions for excessive alcohol consumption among individuals with psychotic disorders. Of the 429 articles identified, seven met inclusion criteria. Data were extracted from each study regarding study sample characteristics, design, results, clinical significance of alcohol consumption results, and methodological limitations.

Results:  Assessment interviews, brief motivational interventions, and lengthier cognitive behavior therapy have been associated with reductions in alcohol consumption among people with psychosis. While brief interventions (i.e. 1–2 sessions) were generally as effective as longer duration psychological interventions (i.e. 10 sessions) for reducing alcohol consumption, longer interventions provided additional benefits for depression, functioning, and other alcohol outcomes.

Conclusion:  Excessive alcohol consumption among people with psychotic disorders is responsive to psychological interventions. It is imperative that such approaches are integrated within standard care for people with psychosis.
The natural course of social anxiety disorder among adolescents and young adults
Authors: Beesdo‐Baum K. , Knappe S. , Fehm L. , Höfler M. , Lieb R. , Hofmann S. G. , Wittchen H.‐U.
Published: May 2012

Beesdo‐Baum K, Knappe S, Fehm L, Höfler M, Lieb R, Hofmann SG, Wittchen H‐U. The natural course of social anxiety disorder among adolescents and young adults.

Objective:  To examine the natural course of social anxiety disorder (SAD) in the community and to explore predictors for adverse long‐term outcomes.

Method:  A community sample of N = 3021 subjects aged 14–24 was followed‐up over 10 years using the DSM‐IV/M‐CIDI. Persistence of SAD is based on a composite score reflecting the proportion of years affected since onset. Diagnostic stability is the proportion of SAD subjects still affected at follow‐up.

Results:  SAD reveals considerable persistence with more than half of the years observed since onset spent with symptoms. 56.7% of SAD cases revealed stability with at least symptomatic expressions at follow‐up; 15.5% met SAD threshold criteria again. 15.1% were completely remitted (no SAD symptoms and no other mental disorders during follow‐up). Several clinical features (early onset, generalized subtype, more anxiety cognitions, severe avoidance and impairment, co‐occurring panic) and vulnerability characteristics (parental SAD and depression, behavioural inhibition, harm avoidance) predicted higher SAD persistence and – less impressively – diagnostic stability.

Conclusion:  A persistent course with a considerable degree of fluctuations in symptom severity is characteristic for SAD. Both consistently meeting full threshold diagnostic criteria and complete remissions are rare. Vulnerability and clinical severity indicators predict poor prognosis and might be helpful markers for intervention needs.
Glycan structures and intrageneric variations of venom acidic phospholipases A2 from Tropidolaemus pitvipers
Authors: Tsai Inn‐Ho , Chang Hui‐Ching , Chen Jin‐Mei , Cheng An‐Chun , Khoo Kay Hooi
Published: May 2012

Most of the phospholipases A2 (PLA2; EC3.1.1.4) variants isolated so far from snake venoms are nonglycosylated enzymes. In the present study, we purified an active glycosylated PLA2 and an inactive nonglycosylated Lys49‐like PLA2 from two geographical venom samples of Tropidolaemus. The PLA2 variants from the two samples have rather different N‐terminal sequences, implying that the samples were probably derived from two species (Tropidolaemus subannulatus and Tropidolaemus wagleri). The active PLA2s from Sulawesi and Sumatra venoms were designated as Tsu‐E6 and Twa‐E6, respectively, as a result of the presence of their conserved Glu6 residue. Tsu‐E6 inhibited ADP‐induced aggregation of mouse and human platelets. Twa‐E6 stimulated the aggregation of mouse platelets but inhibited the aggregation of human platelets. Both PLA2s were found to be glycosylated at Asn14. Using MALDI‐TOF analysis, the released glycans were shown to comprise complex type oligosaccharides without sialylation. This is the first glycan structure of the snake venom PLA2 to be solved. Furthermore, the enzymatic removal of glycans from both PLA2s did not significantly alter their effects on lipid hydrolysis and platelet aggregation. The thermostability of glycosylated Twa‐E6 was also found to be as good as that of other homologous PLA2s. The presence of these oligosaccharides in PLA2s warrants further analyses, which may provide useful insights into the functional regulation of these biomolecules.
Dispersal patterns of exotic forest pests in South Korea
Authors: Choi Won Il , Park Young‐Seuk
Published: May 2012

Abstract Invasive species have potentially devastating effects on ecological communities and ecosystems. To understand the invasion process of exotic forest pests in South Korea, we reviewed four major species of exotic forest pests: the pine needle gall midge (Thecodiplosis japonensis), pine wilt disease caused by the pine wood nematode (Bursaphelenchus xylophilus), the fall webworm (Hyphantria cunea) and the black pine bast scale (Matsucoccus thunbergianae). We consider their biology, ecology, invasion history, dispersal patterns and related traits, and management as exotic species. Among these species, the dispersal process of fall webworm was linear, showing a constant range expansion as a function of time, whereas the other three species showed biphasic patterns, rapidly increasing dispersal speed after slow dispersal at the early invasion stage. Moreover, human activities accelerated their expansion, suggesting that prevention of the artificial movement of damaged trees would be useful to slow expansion of exotic species. We believe that this information would be useful to establish management strategies for invasion species.
Inflammasome Activation of IL‐1 Family Mediators in Response to Cutaneous Photodamage†
Authors: Nasti Tahseen H. , Timares Laura
Published: May 2012

Although keratinocytes are relatively resistant to ultraviolet radiation (UVR) induced damage, repeated UVR exposure result in accumulated DNA mutations that can lead to epidermal malignancies. Keratinocytes play a central role in elaborating innate responses that lead to inflammation and influence the generation of adaptive immune responses in skin. Apart from the minor cellular constituents of the epidermis, specifically Langerhans cells and melanocytes, keratinocytes are the major source of cytokines. UVR exposure stimulates keratinocytes to secrete abundant pro‐inflammatory IL‐1‐family proteins, IL‐1α, IL‐1β, IL‐18, and IL‐33. Normal skin contains only low levels of inactive precursor forms of IL‐1β and IL‐18, which require caspase 1‐mediated proteolysis for their maturation and secretion. However, caspase‐1 activation is not constitutive, but dependents on the UV‐induced formation of an active inflammasome complex. IL‐1 family cytokines can induce a secondary cascade of mediators and cytokines from keratinocytes and other cells resulting in wide range of innate processes including infiltration of inflammatory leukocytes, induction of immunosuppression, DNA repair or apoptosis. Thus, the ability of keratinocytes to produce a wide repertoire of proinflammatory cytokines can influence the immune response locally as well as systematically, and alter the host response to photodamaged cells. We will highlight differential roles played by each IL‐1 family molecule generated by UV‐damaged keratinocytes, and reveal their complementary influences in modulating acute inflammatory and immunological events that follow cutaneous UV exposure.
Centering The Voices Of International Students In Family Studies And Family Therapy Graduate Programs
Authors: McDowell Teresa , Fang Shi‐Ruei , Kosutic Iva , Griggs Julie
Published: May 2012

In this article, we report the results of a survey that accessed the perceptions of family studies and family therapy international master’s and doctoral students across the United States. Our goals included giving collective voice to the experience of international students and gathering their suggestions for improving programs. Themes that emerged from responses to open‐ and closed‐ended questions included feeling (mis)understood and (de)valued; forming personal connections and experiencing marginalization; the importance of including international perspectives in curricula; considering the relevance/transferability of knowledge; and attending to barriers to learning. Based on the results, we share suggestions for improving family studies and family therapy graduate programs relative to program planning, curricula revision, teaching strategies, and faculty development.
Therapist–Worldview Matching: Not as Important as Matching to Clients
Authors: Blow Adrian J. , Davis Sean D. , Sprenkle Douglas H.
Published: May 2012

In this essay, we respond to Simon’s article (2012). We discuss our view that therapy works best when therapists can match therapeutic interventions to the worldview of clients. We see this matching to client worldview as rooted in research evidence, and we suggest that therapists can practice authentically and effectively using more than one divergent therapy approach. We conclude the paper by pointing out points of disagreement we have with Simon’s use of Davis and Piercy’s (Journal of Marital and Family Therapy, 2007a; 33, 298; Journal of Marital and Family Therapy, 2007b, 32, 515) study, a study Simon uses to ground his arguments.
Factors contributing to carbon fluxes from bioenergy harvests in theU.S. Northeast: an analysis using field data
Authors: Mika Anna M. , Keeton William S.
Published: May 2012

With growing interest in wood bioenergy there is uncertainty over greenhouse gas emissions associated with offsetting fossil fuels. Although quantifying postharvest carbon (C) fluxes will require accurate data, relatively few studies have evaluated these using field data from actual bioenergy harvests. We assessedCreductions and net fluxes immediately postharvest from whole‐tree harvests (WTH), bioenergy harvests withoutWTH, and nonbioenergy harvests at 35 sites across the northeasternUnitedStates. We compared the aboveground forestCin harvested with paired unharvested sites, and analyzed theCtransferred to wood products andCemissions from energy generation from harvested sites, including indirect emissions from harvesting, transporting, and processing. All harvests reduced live treeC; however, only bioenergy harvests usingWTHsignificantly reducedCstored in snags (P < 0.01). On average,WTHsites also decreased downed coarse woody debrisCwhile the other harvest types showed increases, although these results were not statistically significant. Bioenergy harvests usingWTHgenerated fewer wood products and resulted in more emissions released from bioenergy than the other two types of harvests, which resulted in a greater net flux ofC(P < 0.01). AClassification andRegressionTree analysis determined that it was not the type of harvest or amount of bioenergy generated, but rather the type of skidding machinery and specifics of silvicultural treatment that had the largest impact on netCflux. Although additional research is needed to determine the impact of bioenergy harvesting over multiple rotations and at landscape scales, we conclude that operational factors often associated withWTHmay result in an overall intensification ofCfluxes. The intensification of bioenergy harvests, and subsequentCemissions, that result from these operational factors could be reduced if operators select smaller equipment and leave a portion of tree tops on site.
Mitochondrial function in human skeletal muscle following high‐altitude exposure
Authors: Jacobs Robert A. , Boushel Robert , Wright‐Paradis Cynthia , Calbet Jose A. L. , Robach Paul , Gnaiger Erich , Lundby Carsten
Published: May 2012

New Findings

What is the central question of this study?

Are the enzymatic alterations in human skeletal muscle observed following 9–11 days of exposure to high altitude reflected in mitochondrial function?

What is the main finding and its importance?

The main findings of this study are that the capacity fat oxidation, individualized respiration capacity through mitochondrial complex I and II, and electron coupling efficiency are not greatly affected by 9–11 days of exposure to high altitude. The importance of this data is that high altitude exposure failed to affect integrated measures of mitochondrial functional capacity in skeletal muscle despite significant decrements to enzyme concentrations involved in the tricarboxylic acid (TCA) cycle and oxidative phosphorylation.

Studies regarding mitochondrial modifications in human skeletal muscle following acclimatization to high altitude are conflicting, and these inconsistencies may be due to the prevalence of representing mitochondrial function through static and isolated measurements of specific mitochondrial characteristics. The aim of this study, therefore, was to investigate mitochondrial function in response to high‐altitude acclimatization through measurements of respiratory control in the vastus lateralis muscle. Skeletal muscle biopsies were obtained from 10 lowland natives prior to and again after a total of 9–11 days of exposure to 4559 m. High‐resolution respirometry was performed on the muscle samples to compare respiratory chain function and respiratory capacities. Respirometric analysis revealed that mitochondrial function was largely unaffected, because high‐altitude exposure did not affect the capacity for fat oxidation or individualized respiration capacity through either complex I or complex II. Respiratory chain function remained unaltered, because neither coupling nor respiratory control changed in response to hypoxic exposure. High‐altitude acclimatization did, however, show a tendency (P= 0.059) to limit mass‐specific maximal oxidative phosphorylation capacity. These data suggest that 9–11 days of exposure to high altitude do not markedly modify integrated measures of mitochondrial functional capacity in skeletal muscle despite significant decrements in the concentrations of enzymes involved in the tricarboxylic acid cycle and oxidative phosphorylation.
An Investigation Into the Effects of Modelling Cylindrical Nozzle to Cylindrical Vessel Intersections Using 2D Axisymmetric Finite Element Models and a Proposed Method for Correcting the Results
Authors: Sommerville Daniel , Walter Matthew
Published: May 2012

Two dimensional (2-D) axisymmetric finite element models (FEMs) are often used as a simplification to modeling cylindrical nozzles that intersect a cylindrical pressure vessel. However, an axisymmetric model has the effect of representing the vessel as a spherical shell rather than a cylindrical shell. Previous work has been done to determine 2-D axisymmetric to three dimensional (3-D) stress correction factors (CFs) for the total stress at the nozzle blend radius to account for this inconsistency. The present paper expands on that work to investigate the effects of the 2-D axisymmetric modeling simplification on the through wall stress distribution at the nozzle corner. The through-wall stress distribution is necessary for some fracture mechanics analyses performed for corner cracked nozzles and for using the simplified elastic-plastic analysis given in NB-3228.5. A simplified method is proposed which can be used to obtain a nozzle specific correction factor, rather than a bounding correction factor, that can be applied to 2-D finite element analysis stress results to correct for the inaccuracy introduced by modeling the intersection as an axisymmetric section.
A Finite Element Study of the Effect of Partial Autofrettage on the Fatigue Life of Thick-Walled Cylinders Containing Erosions and Cracks
Authors: Ma Q. , Levy C. , Perl M.
Published: May 2012

For the investigation of cracked problems in thick-walled pressurized cylindrical vessels, the displacement-based finite element method has become one of the main computational tools to extract stress intensity results for their fatigue life predictions. The process of autofrettage, practically from partial autofrettage level of 30% to full autofrettage level of 100%, is known to introduce favorable compressive residual hoop stresses at the cylinder bore in order to increase its service life. In order to extract the fatigue life, stress intensity factors (SIFs) need to be obtained a priori. The necessity for determining SIFs and their practical importance are well understood. However, it is usually not a trivial task to obtain the SIFs required since the SIFs largely depend on not only the external loading scenarios, but also the geometrical configurations of the cylinder. Our recent work has shown that the Bauschinger Effect (BE) may come into play and affect the effective SIFs significantly for an eroded fully autofrettaged thick-walled cylinder. In this study, we further investigate the SIFs for the Bauschinger effect dependent autofrettage (BEDA) and the Bauschinger effect independent autofrettage (BEIA) at various autofrettage levels. The crack is considered to emanate from the erosion’s deepest point in a multiply eroded cylinder. The commercial finite element package, ANSYS v12, was employed to perform the necessary analysis. A two-dimensional model, analogous to the authors’ previous studies, has been adopted for this investigation. The residual stress field of autofrettage process, based on von Mises yield criterion, is simulated by thermal loading. The combined SIFs are evaluated for a variety of relative crack lengths with cracks emanating from the tip of erosions with various geometrical configurations and span angles. The effective SIFs for relatively short cracks are found to be increased by the presence of the erosion and further increased due to the BE at the same autofrettage level, which may result in a significant decrease in the vessel’s fatigue life. Deep cracks are found to be almost unaffected by the erosion, but may be considerably affected by BE as well as by the level of partial autofrettage.
Thermal Analysis of a 9975 Package in a Facility Fire Accident
Authors: Gupta Narendra K.
Published: May 2012

Surplus plutonium bearing materials in the U.S. Department of Energy (DOE) complex are stored in the 3013 containers that are designed to meet the requirements of the DOE standard DOE-STD-3013. The 3013 containers are in turn packaged inside 9975 packages that are designed to meet the NRC 10 CFR Part 71 regulatory requirements for transporting the Type B fissile materials across the DOE complex. The design requirements for the hypothetical accident conditions (HAC) involving a fire are given in 10 CFR 71.73. The 9975 packages are stored at the DOE Savannah River Site in the K-Area Material Storage (KAMS) facility for long term of up to 50 years. The design requirements for safe storage in KAMS facility containing multiple sources of combustible materials are far more challenging than the HAC requirements in 10 CFR 71.73. While the 10 CFR 71.73 postulates an HAC fire of 1475°F and 30 minutes duration, the facility fire calls for a fire of 1500°F and 86 minutes duration. This paper describes a methodology and the analysis results that meet the design limits of the 9975 components and demonstrate the robustness of the 9975 package.
Hydrogen Concentrations During Storage of 3013 Oxide Samples
Authors: Askew N. M. , Laurinat J. E. , Hensel S. J.
Published: May 2012

As part of a surveillance program intended to ensure the safe storage of plutonium bearing nuclear materials in the Savannah River Site (SRS) K-Area Materials Storage, samples of these materials are shipped to Savannah River National Laboratory (SRNL) for analysis. These samples are in the form of solids or powders which will have absorbed moisture. Potentially flammable hydrogen gas is generated due to radiolysis of the moisture. The samples are shipped for processing after chemical analysis. To preclude the possibility of a hydrogen deflagration or detonation inside the shipping containers, the shipping times are limited to ensure that hydrogen concentration in the vapor space of every layer of confinement is below the lower flammability limit of 4 volume percent (vol%) [1]. This study presents an analysis of the rate of hydrogen accumulation due to radiolysis and calculation of allowable shipping times for typical K-Area materials.
Derivation of the New Pressurized Thermal Shock Screening Criteria
Authors: Dickson Terry , Yin Shengjun , Kirk Mark , Chou Hsuing-Wei
Published: May 2012

As a result of a multi-year, multi-disciplinary effort on the part of the United States Nuclear Regulatory Commission (USNRC), its contractors, and the nuclear industry, a technical basis has been established to support a risk-informed revision to pressurized thermal shock (PTS) regulations originally promulgated in the mid-1980s. The revised regulations provide alternative (optional) reference-temperature (RT)-based screening criteria, which is codified in 10 CFR 50.61(a). How the revised screening criteria were determined from the results of the probabilistic fracture mechanics (PFM) analyses will be discussed in this paper.
Mechanistic Insights Into Risk-Informed Revision of ASME Section XI–Appendix G
Authors: Dickson Terry , Kirk Mark , Focht Eric
Published: May 2012

The current regulations, as set forth by the United States Nuclear Regulatory Commission (NRC), to insure that light-water nuclear reactor pressure vessels (RPVs) maintain their structural integrity, throughout their operating life, when subjected to planned normal reactor startup (heat-up) and shutdown (cool-down) transients are specified in Appendix G to 10 CFR Part 50, which incorporates by reference Appendix G to Section XI of the American Society of Mechanical Engineers (ASME) Code. The technical basis for these regulations are generally considered to be conservative and some plants are finding it operationally difficult to heat-up and cool-down within the accepted limits. Consequently, the nuclear industry has developed, and submitted to the ASME Code for approval, an alternative risk-informed methodology that reduces the conservatism and is consistent with methods previously used to develop a risk-informed revision to the regulations for accidental transients such as pressurized thermal shock (PTS). The objective of the alternative methodology is to increase operational flexibility while continuing to provide reasonable assurance of adequate protection to public health and safety. The NRC and its contractor at Oak Ridge National Laboratory (ORNL) are reviewing the industry proposed risk-informed methodology. Previous results of this review, have been reported at PVP, and a NRC report summarizing all results is currently in preparation. The objective of this paper is to discuss and illustrate mechanistic insights into trends shown previously associated with normal cool-down.
The Combination of Modern Sealing Materials to Assist in the Reduction of Flange Deterioration
Authors: Currie Russ
Published: May 2012

The paper discusses the use of composite gaskets containing both metallic and non-metallic components to mitigate corrosion effects and provide high tightness class sealing on restricted flange face sealing areas.
The Vital Role of the Corrosion/Materials Engineer in the Life Cycle Management of Pressure Equipment
Authors: Reynolds John
Published: May 2012

In my 40 years of experience I’ve come to firmly believe that nearly every operating site processing hydrocarbons needs the services, to some extent, of a competent, experienced corrosion/materials (C/M) engineer in order to achieve excellence in pressure equipment integrity and reliability (PEI&R). Without such services there are many PEI traps to fall into caused by lack of knowledge of corrosion and materials degradation issues. This paper outlines those traps that can lead not only to avoidable cost issues, but unanticipated breaches of containment and the ensuing undesirable safety and environmental consequences. The most well rounded C/M engineer should be knowledgeable, not just in metallurgy and materials selection, but also in process chemistry, corrosion and degradation mechanisms, corrosion barriers, materials degradation prevention, repair and replacement decisions and cost-effective mitigation practices. In this paper, I will indicate how a competent C/M engineer could easily save the company the cost of his/her services ten times over while recognizing that not all small sites may need a full time C/M engineer on staff, but should at least have access to one through contractual agreements. I will show how proactive corrosion control activities in the top ten vital C/M engineering aspects are necessary to achieve excellence (and avoid pressure equipment failures) in PEI&R.
Limit, Shakedown and Ratchet Analyses of Defective Pipeline Under Internal Pressure and Cyclic Thermal Loading
Authors: Chen Weihang , Chen Haofeng , Li Tianbai , Ure James
Published: May 2012

In this study, the limit load, shakedown and ratchet limit of a defective pipeline subjected to constant internal pressure and a cyclic thermal gradient are analyzed. Ratchet limit and maximum plastic strain range are solved by employing the new Linear Matching Method (LMM) for the direct evaluation of the ratchet limit. Shakedown and ratchet limit interaction diagrams of the defective pipeline identifying the regions of shakedown, reverse plasticity, ratcheting and plastic collapse mechanism are presented and parametric studies involving different types and dimensions of part-through slot in the defective pipeline are investigated. The maximum plastic strain range over the steady cycle with different cyclic loading combinations is evaluated for a low cycle fatigue assessment. The location of the initiation of a fatigue crack for the defective pipeline with different slot type is determined. The proposed linear matching method provides a general-purpose technique for the evaluation of these key design limits and the plastic strain range for the low cycle fatigue assessment. The results for the defective pipeline shown in the paper confirm the applicability of this procedure to complex 3-D structures.
Stress and Fracture Mechanics Analyses of Boiling Water Reactor and Pressurized Water Reactor Pressure Vessel Nozzles
Authors: Yin Shengjun Sean , Stevens Gary L. , Bass B. Richard , Kirk Mark T.
Published: May 2012

This paper describes stress analysis and fracture mechanics work performed to assess boiling water reactor (BWR) and pressurized water reactor (PWR) nozzles located in the reactor pressure vessel (RPV) adjacent to the core beltline region. Various RPV nozzle geometries were investigated: 1. BWR recirculation outlet nozzle; 2. BWR core spray nozzle; 3. PWR inlet nozzle; 4. PWR outlet nozzle; and 5. BWR partial penetration instrument nozzle. The above nozzle designs were selected based on their proximity to the core beltline region, i.e., those nozzle configurations that are located close enough to the core region such that they may receive sufficient fluence prior to end-of-license (EOL) to require evaluation as part of establishing the allowed limits on heatup, cooldown, and hydrotest (leak test) conditions. These nozzles analyzed represent one each of the nozzle types potentially requiring evaluation. The purpose of the analyses performed on these nozzle designs was as follows: • To model and understand differences in pressure and thermal stress results using a two-dimensional (2-D) axi-symmetric finite element model (FEM) versus a three-dimensional (3-D) FEM for all nozzle types. In particular, the ovalization (stress concentration) effect of two intersecting cylinders, which is typical of RPV nozzle configurations, was investigated; • To verify the accuracy of a selected linear elastic fracture mechanics (LEFM) hand solution for stress intensity factor for a postulated nozzle corner crack for both thermal and pressure loading for all nozzle types; • To assess the significance of attached piping loads on the stresses in the nozzle corner region; and • To assess the significance of applying pressure on the crack face with respect to the stress intensity factor for a postulated nozzle corner crack.
Additional Improvements to Appendix G of ASME Section XI Code for Nozzles
Authors: Mehta Hardayal S. , Griesbach Timothy J. , Sommerville Daniel V. , Stevens Gary L.
Published: May 2012

This paper is the second in a continuing series of papers to highlight additional bases and recommended improvements to Appendix G. In 2008, the authors prepared a paper that reviewed some of the original basis documents for Appendix G for calculating pressure-temperature (P-T) limits and identified recommended areas for improvement. The 2008 paper discussed the fact that the original Appendix G in Section XI of the ASME Code was primarily based on Welding Research Council (WRC) Bulletin 175, and identified the changes that have been made to Appendix G over the past 20 years. However, the nozzle corner solutions have remained the same as those given in WRC 175. Proposed revisions to Appendix G are included in this paper regarding the stress intensity factor (K) calculation procedures for pressure and thermal gradient loading at a nozzle corner based on the various solutions described in the authors’ previous paper and on other more recent investigations. The current paper is focused on incorporating the results of additional studies that have been completed associated with nozzle corner solutions. This additional work has become more important because plants must address the effects of nozzles in the reactor pressure vessel (RPV) as a part of pressure-temperature (P-T) curve development, especially if the nozzles are located sufficiently close to the active core region such that they accumulate significant fluence. In addition, the treatment of operating stresses exceeding the material yield stress is discussed and the basis for the limit of material yield strength to 90 ksi in G-2110(b) is provided. Finally, this paper identifies other areas for future improvements in Appendix G, including those areas remaining to be addressed from prior work.
A Load Combination Method for Seismic Design of Multiple Supported Piping Systems With Friction Characteristics: Part 2—Correlated Excitations Considering Characteristics of Supports
Authors: Yamauchi Tatsuya , Tsuchikawa Kazumasa , Yokota Atsushi , Masuda Arata , Sone Akira
Published: May 2012

Seismic response analysis of piping systems with friction characteristics to multiple support excitations is presented. By this analysis, the maximum responses of piping system are calculated and “response reduction factor” due to friction are taken into account by use of a stationary random vibration theory approach. Using a simple analytical SDOF piping system with friction characteristics to two support excitations, This method is supplied to various support cases with two support excitations and friction characteristics and the maximum responses of piping is calculated. From these calculation results, it is clear that the maximum acceleration responses of nonlinear piping systems can be reduced due to the friction effect. Finally, the conventional equation of the response reduction factor and the maximum response calculated by the proposed method are presented for practical use.
Acoustic and Vibration Analysis of Fluid Induced Blower and Piping Unwanted Motion
Authors: Endres Ned M.
Published: May 2012

This paper presents investigational findings and a discussion of recommendations relating to sound and vibration measurements performed in connection with a fluid induced vibration issue on two air blowers and attached exhaust piping at an industrial facility. These vibration and sound measurements were prompted by recent check valve failures for the air blower units, and unacceptable sound levels emanating from these units and affecting nearby residents. This data was acquired during steady state operating conditions of the blowers under normal operating conditions. An FFT data acquisition system, a piezoelectric microphone and three piezoelectric triaxial accelerometers were used to collect vibration measurements at each of the 70 locations on the blowers, motors, blower bases, and exhaust piping, while sound measurements were simultaneously acquired with the microphone. Piping and blower vibration readings were used to construct an operating deflection shape analysis of the blowers, foundations and attached piping system. The resulting vibration and sound analysis revealed that acoustic excitation of the piping system appeared to be the likely source of the high vibration, high sound pressure levels; piping cracks and check valve failures. Corrective actions were implemented that reduced the sound pressure levels, vibration levels, and reduced/eliminate the piping damage and valve failures.