bluuebunny/crossref_metadata_2025 huggingface dataset:
Analysis of 65 pregnancies in 34 women with five different forms of inherited platelet function disorders
Authors: Civaschi Elisa , Klersy Catherine , Melazzini Federica , Pujol‐Moix Nuria , Santoro Cristina , Cattaneo Marco , Lavenu‐Bombled Cécile , Bury Loredana , Minuz Pietro , Nurden Paquita , Cid Ana R. , Cuker Adam , Latger‐Cannard Véronique , Favier Remi , Nichele Ilaria , Noris Patrizia ,   the European Haematology Association – Scientific Working Group on Thrombocytopenias and Platelet Function Disorders
Published: April 2015

This study evaluated 65 pregnancies in 34 women with five different inherited platelet function disorders. Gestation was similar to that of the general population. Severe bleeds requiring blood transfusions were observed in 50% of deliveries in Glanzmann thrombasthenia (GT), but not in the patients with delta storage pool disease, Hermansky‐Pudlak syndrome, P2Y12 defect or defect of thromboxane A2 receptor. Of note, severe haemorrhage also occurred in women with GT who had received prophylactic platelet transfusions, suggesting that better preventive treatments are required. Diagnosis and degree of spontaneous bleeding tendency before pregnancy were reliable parameters to predict the delivery‐related bleeding risk.
Climate‐associated tundra thaw pond formation and range expansion of boreal zooplankton predators
Authors: Taylor Derek J. , Ballinger Matthew J. , Medeiros Andrew S. , Kotov Alexey A.
Published: April 2015

Most of the freshwater component of the Earth's surface is composed of shallow tundra ponds. These high latitude ecosystems have been exposed to a variety of abiotic disturbances associated with recent environmental change. However, the biological significance of these changes remains poorly understood. Here, we characterize the abiotic disturbance to the shallow tundra ponds of northwest Alaska. We used historical aerial imagery to determine that up to 53% of the sampled ponds have formed during the recent warmer decades (since the 1970s). We discovered that two top predator species (phantom midges of the genus Chaoborus) of the freshwater zooplankton have recently undergone range expansion, forming widespread (a scale of hundreds of km) stable tundra populations. We assessed the population persistence of these boreal predators by longitudinal sampling over 14 yr. Recent thaw ponds had significantly dissimilar zooplankton communities to communities of ponds that formed before 1950. Both predator and herbivore species differed by age of pond. Younger pond ages and warmer surface temperatures were the significant predictors of the presence of temperate Chaoborus americanus in tundra ponds. Ponds containing tundra populations of C. americanus and C. cf. flavicans were associated with recent formation (83–90%). Recent ponds in river valleys appeared more important than recent ponds near roads as colonization corridors for C. americanus. Only 24% of the tundra keystone predator, Heterocope septentrionalis, populations were from recent ponds. Our results suggest that climate‐associated disturbance can lead to a widespread stable range expansion of boreal species despite the propinquity of older ponds with top‐down control exerted by an endemic keystone predator.
Differences in inhibitory avoidance, cortisol and brain gene expression in TL and AB zebrafish
Authors: Gorissen M. , Manuel R. , Pelgrim T. N. M. , Mes W. , de Wolf M. J. S. , Zethof J. , Flik G. , van den Bos R.
Published: April 2015

Recently, we established an inhibitory avoidance paradigm in Tupfel Long‐Fin (TL) zebrafish. Here, we compared task performance of TL fish and fish from the AB strain; another widely used strain and shown to differ genetically and behaviourally from TL fish. Whole‐body cortisol and telencephalic gene expression related to stress, anxiety and fear were measured before and 2 h post‐task. Inhibitory avoidance was assessed in a 3‐day paradigm: fish learn to avoid swimming from a white to a black compartment where a 3V‐shock is given: day 1 (first shock), day 2 (second shock) and day 3 (no shock, sampling). Tupfel Long‐Fin fish rapidly learned to avoid the black compartment and showed an increase in avoidance‐related spatial behaviour in the white compartment across days. In contrast, AB fish showed no inhibitory avoidance learning. AB fish had higher basal cortisol levels and expression levels of stress‐axis related genes than TL fish. Tupfel Long‐Fin fish showed post‐task learning‐related changes in cortisol and gene expression levels, but these responses were not seen in AB fish. We conclude that AB fish show higher cortisol levels and no inhibitory avoidance than TL fish. The differential learning responses of these Danio strains may unmask genetically defined risks for stress‐related disorders.
How Do Auditor Fees Affect Accruals Quality? Additional Evidence
Authors: Mande Vivek , Son Myungsoo
Published: April 2015

This study examines whether the Sarbanes‐Oxley Act (SOX) moderates the association between auditor fees and accruals quality. Using a large sample of firms, we first confirm the results of Srinidhi and Gul, showing that in the pre‐SOX years, higher audit fees (non‐audit fees) denoting higher effort (rents) imply higher (lower) accruals quality. However, we find that post‐SOX, these associations weaken or disappear in some specifications. This study also finds that lengthy auditor tenure attenuates the relationship between audit fees and accruals quality. These findings provide new evidence to investors and policymakers on the impact of SOX on auditor fees and audit quality, and have implications for academic studies that use auditor fees as a proxy for audit quality.
Removal of body surface area normalisation improves raw‐measured glomerular filtration rate estimation by the Chronic Kidney Disease Epidemiology Collaboration equation and drug dosing in the obese
Authors: Chew‐Harris J. S. C. , Chin P. K. L. , Florkowski C. M. , George P. , Endre Z.
Published: April 2015

Background/Aim

We aimed to compared estimated glomerular filtration rate (eGFR) according to the Chronic Kidney Disease Epidemiology Collaboration equation (CKD‐EPI), with (mL/min/1.73 m2) and without body surface area (BSA) normalisation (CKD‐EPI_noBSA, mL/min) against measured 99m Technetium ‐ diethylenepentaacetic acid (Tc‐DTPA GFR) (mL/min) in 222 individuals, including 80 with malignancy.

Methods

BSA was calculated for each individual using the Du Bois equation. The CKD‐EPI and CKD‐EPI_noBSA equations were compared with measured Tc‐DTPA GFR with respect to bias, proportion within 30% of GFR (P30) and root mean square error for predicting levels of GFR, and concordance in relation to carboplatin dosing.

Results

The mean (SD) for BSA and measured GFR for the entire group was 1.99 (0.25) m2 and 127 (41) mL/min respectively. The P30 for Tc‐DTPA GFR was significantly higher with the CKD‐EPI_noBSA (80%) than with the CKD‐EPI equation (63%, P = 0.0001). In those with body mass index (BMI) > 30 kg/m2, the P30 values for the CKD‐EPI_noBSA and CKD‐EPI were 74% and 42% respectively (P < 0.0001). Carboplatin dosing concordance for the cancer patients using the CKD‐EPI and CKD‐EPI_noBSA equation was 71% and 56% respectively (P = 0.07). In 78 individuals with BMI > 30 kg/m2, concordance in relation to carboplatin dosing using CKD‐EPI_noBSA was 65% compared with 26% with the CKD‐EPI (P < 0.0001).

Conclusion

The CKD‐EPI without normalisation (CKD‐EPI_noBSA) equation was superior to the CKD‐EPI equation in estimating raw‐measured Tc‐DTPA GFR (mL/min).
Is telemedicine helping or hindering the delivery of stroke thrombolysis in rural areas? A qualitative analysis
Authors: Moloczij N. , Mosley I. , Moss K. M. , Bagot K. L. , Bladin C. F. , Cadilhac D. A
Published: April 2015

Background

Fast diagnosis and delivery of treatment to patients experiencing acute stroke can reduce subsequent disability. While telemedicine can improve rural community access to specialists and facilitate timely diagnosis and treatment decisions, it is not widely used for stroke in Australia.

Aim

Identifying the barriers and facilitators to clinician engagement with, and utilisation of, telemedicine consultations could expedite implementation in rural and remote locations.

Methods

Purposive sampling was used to identify and recruit medical and nursing staff varying in telemedicine experience across one hospital department. Twenty‐four in‐depth, face‐to‐face interviews were conducted examining aspects surrounding stroke telemedicine uptake. Inductive qualitative thematic analysis was undertaken, and two further researchers verified coding.

Results

The main barriers identified were contrasting opinions about the utility of thrombolysis for treating acute stroke, lack of confidence in the telemedicine system, perceived limited need for specialist advice and concerns about receiving advice from an unfamiliar doctor. Facilitators included assistance with diagnosis and treatment, the need for a user‐friendly system and access to specialists for complex cases.

Conclusions

Acceptability of telemedicine for acute stroke was multifaceted and closely aligned with regional clinician beliefs about the value of thrombolysis for stroke, highlighting an important area for education. Addressing beliefs about treatment efficacy and other perceived barriers is important for establishing a stroke telemedicine programme.
Developmental changes in genetic and environmental influences on rule‐breaking and aggression: age and pubertal development
Authors: Harden K. Paige , Patterson Megan W. , Briley Daniel A. , Engelhardt Laura E. , Kretsch Natalie , Mann Frank D. , Tackett Jennifer L. , Tucker‐Drob Elliot M.
Published: April 2015

Background

Antisocial behavior (ASB) can be meaningfully divided into nonaggressive rule‐breaking versus aggressive dimensions, which differ in developmental course and etiology. Previous research has found that genetic influences on rule‐breaking, but not aggression, increase from late childhood to mid‐adolescence. This study tested the extent to which the developmental increase in genetic influence on rule‐breaking was associated with pubertal development compared to chronological age.

Method

Child and adolescent twins (n = 1,031), ranging in age from 8 to 20 years (M age = 13.5 years), were recruited from public schools as part of the Texas Twin Project. Participants reported on their pubertal development using the Pubertal Development Scale and on their involvement in ASB on items from the Child Behavior Checklist. Measurement invariance of ASB subtypes across age groups (≤12 years vs. >12 years old) was tested using confirmatory factor analyses. Quantitative genetic modeling was used to test whether the genetic and environmental influences on aggression and rule‐breaking were moderated by age, pubertal status, or both.

Results

Quantitative genetic modeling indicated that genetic influences specific to rule‐breaking increased as a function of pubertal development controlling for age (a gene × puberty interaction), but did not vary as a function of age controlling for pubertal status. There were no developmental differences in the genetic etiology of aggression. Family‐level environmental influences common to aggression and rule‐breaking decreased with age, further contributing to the differentiation between these subtypes of ASB from childhood to adolescence.

Conclusions

Future research should discriminate between alternative possible mechanisms underlying gene × puberty interactions on rule‐breaking forms of antisocial behavior, including possible effects of pubertal hormones on gene expression.
Melatonin reduces hepatic mitochondrial dysfunction in diabetic obese rats
Authors: Agil Ahmad , El‐Hammadi Mazen , Jiménez‐Aranda Aroa , Tassi Mohamed , Abdo Walied , Fernández‐Vázquez Gumersindo , Reiter Russel J.
Published: April 2015

Hepatic mitochondrial dysfunction is thought to play a role in the development of liver steatosis and insulin resistance, which are both common characteristics of obesity and type 2 diabetes mellitus (T2DM). It was hypothesized that the antioxidant properties of melatonin could potentially improve the impaired functions of hepatic mitochondria in diabetic obese animals. Male Zucker diabetic fatty (ZDF) rats and lean littermates (ZL) were given either melatonin (10 mg/kg BW/day) orally for 6 wk (M‐ZDF and M‐ZL) or vehicle as control groups (C‐ZDF and C‐ZL). Hepatic function was evaluated by measurement of serum alanine transaminase and aspartate transaminase levels, liver histopathology and electron microscopy, and hepatic mitochondrial functions. Several impaired functions of hepatic mitochondria were observed in C‐ZDF in comparison with C‐ZL rats. Melatonin treatment to ZDF rats decreases serum levels of ALT (P < 0.001), alleviates liver steatosis and vacuolation, and also mitigates diabetic‐induced mitochondrial abnormalities, glycogen, and lipid accumulation. Melatonin improves mitochondrial dysfunction in M‐ZDF rats by increasing activities of mitochondrial citrate synthase (P < 0.001) and complex IV of electron transfer chain (P < 0.05) and enhances state 3 respiration (P < 0.001), respiratory control index (RCR) (P < 0.01), and phosphorylation coefficient (ADP/O ratio) (P < 0.05). Also melatonin augments ATP production (P < 0.05) and diminishes uncoupling protein 2 levels (P < 0.001). These results demonstrate that chronic oral melatonin reduces liver steatosis and mitochondria dysfunction in ZDF rats. Therefore, it may be beneficial in the treatment of diabesity.
Erect Penile Dimensions in a Cohort of 778 Middle Eastern Men: Establishment of a Nomogram
Authors: Habous Mohamad , Tealab Alaa , Williamson Ben , Binsaleh Saleh , El Dawy Sherif , Mahmoud Saad , Abdelwahab Osama , Nassar Mohammed , Mulhall John P. , Veale David , Muir Gordon
Published: April 2015

Introduction

Accurate data regarding the size of the erect penis are of great importance to several disciplines working with male patients, but little high-quality research exists on the subject, particularly in different ethnic groups and for erect penis size.

Aim

The aim of this study was to create a nomogram of erect penile dimensions in a large sample of Middle Eastern men.

Methods

A retrospective cohort study of 778 men (mean age 43.7; range 20–82) attending urological outpatient clinics in Saudi Arabia was conducted. Exclusion criteria were age under 18 years, a presenting complaint of small or short penis, Peyronie's disease or complaint of congenital curvature, clinical hypogonadism, and previous penile surgery or trauma.

Main Outcome Measures

Three erect penile dimensions following induction of erection using intracavernosal injection of Quadrimix.

Results

Mean patient body mass index (BMI) was 29.09 (standard deviation [SD] 5.76). The mean suprapubic skin-to-penile tip erect length was 12.53 cm (SD 1.93); the mean erect length from the symphysis pubis to the penile tip was 14.34 cm (SD 1.86); and the mean erect shaft circumference was 11.50 cm (SD 1.74). A nomogram was constructed and statistical analysis performed, demonstrating a weak negative correlation between BMI and erect penile length measured from the suprapubic skin (r = −0.283, P < 0.000) but not from bone to tip, and a weak negative correlation between age and both erect penile length measurements (skin to tip r = −0.177, P < 0.0005; bone to tip r = −0.099, P = 0.006).

Conclusion

A nomogram for Middle Eastern men can be used as a standard when advising men with small penis anxiety. The importance of measuring erect size and allowing for infra-pubic fat interference in measurement is emphasized. We envisage that this tool can be used to educate and reassure concerned men about the size of their penises.
Comorbidity in Patients with Dhat Syndrome: A Nationwide Multicentric Study
Authors: Grover Sandeep , Avasthi Ajit , Gupta Sunil , Dan Amitava , Neogi Rajarshi , Behere Prakash B. , Lakdawala Bhavesh , Tripathi Adarsh , Chakraborty Kaustav , Sinha Vishal , Bhatia Manjeet Singh , Pattojoshi Amrit , Rao T.S.S. , Rozatkar Abhijit
Published: April 2015

Introduction

There are limited numbers of studies on Dhat syndrome. Major limitations of the existing literature are heterogeneous assessment methods used to describe the comorbidity and small sample size from isolated centers.

Aim

To assess comorbidity with a common methodology in patients with Dhat syndrome from multiple centers across India.

Methods

Using a cross-sectional design, this multicentric study involved assessment of 780 male patients, aged more than 16 years, across 15 study centers.

Main Outcome Measures

ICD-10 criteria (for evaluation of psychiatric morbidity and sexual dysfunction)

Results

About one-third (32.8%) of the cases had no comorbidity. One-fifth (20.5%) of the patients had comorbid depressive disorders and another one-fifth (20.5%) had comorbid neurotic, stress-related and somatoform disorders. Half (51.3%) of the study sample had comorbid sexual dysfunction. When various combinations of comorbidities were evaluated, it was seen that more than one-fourth (28.7%) of the patients had only comorbid sexual dysfunction and one-sixth (15.9%) had only comorbid depressive/anxiety disorders. A little more than one-fifth (22.6%) had comorbidity of both sexual dysfunction and depressive/anxiety disorders.

Conclusion

Comorbid sexual dysfunction is seen in half of the cases of Dhat syndrome, and it is more common than comorbid depressive and anxiety disorders.
Effect of a Probiotic on Prevention of Diarrhea and Clostridium difficile and Clostridium perfringens Shedding in Foals
Authors: Schoster A. , Staempfli H.R. , Abrahams M. , Jalali M. , Weese J.S. , Guardabassi L.
Published: April 2015

Background

Up to 60% of foals develop diarrhea within 6 months after birth. Preventive measures are limited but potentially probiotics could be used.

Objective

To evaluate the effect of a newly designed probiotic on the incidence of foal diarrhea in a randomized field trial.

Animals

Seventy‐two healthy neonatal foals.

Methods

Randomized, placebo‐controlled field trial. Foals were administered a placebo or probiotic for 3 weeks and monitored for an additional week. A total of 3 fecal samples were taken from each foal at biweekly intervals. Statistical modeling was applied for comparison of incidence and duration of diarrhea and fecal shedding of Clostridium perfringens and Clostridium difficile between treatment and age groups.

Results

The overall incidence of diarrhea was 41 of 72 (59%) and did not differ (P = 0.37) between treatment groups. Foals treated with probiotics were more likely to develop diarrhea requiring veterinary intervention (P = 0.007). Age had a significant effect on incidence of diarrhea (P < 0.001); foals 8–15 days old having the highest probability of developing diarrhea. Duration of diarrhea and soft feces were not significantly different between groups. The prevalence of C. perfringens shedding was 55% with no difference between treatment groups (P = 0.23). The prevalence of C. difficile shedding was 11%.

Conclusion and Clinical Importance

There was no benefit of administering a 3‐week course of probiotics, but potential adverse effects were noted. Whether the probiotics lacked a clinical effect, or the choice of strains or dose was inadequate, is unknown. Clostridial shedding was not influenced by probiotics despite in vitro activity of probiotics.
Signalment, Clinical Presentation, Concurrent Diseases, and Diagnostic Findings in 28 Dogs with Dynamic Pharyngeal Collapse (2008–2013)
Authors: Rubin J.A. , Holt D.E. , Reetz J.A. , Clarke D.L.
Published: April 2015

Background

Most information about pharyngeal collapse in dogs is anecdotal and extrapolated from human medicine. A single case report describing dynamic pharyngeal collapse in a cat has been published, but there is no literature describing this disease process in dogs.

Objective

To describe the signalment, clinical presentation, concurrent disease processes, and imaging findings of a population of client‐owned dogs with pharyngeal collapse.

Animals

Twenty‐eight client‐owned dogs with pharyngeal collapse.

Methods

Radiology reports of dogs for which fluoroscopy of the respiratory system was performed were reviewed retrospectively. Patients with a fluoroscopic diagnosis of pharyngeal collapse were included in the study population. Data regarding clinical signs, diagnostic, and pathologic findings were evaluated.

Results

Twenty‐eight dogs met the inclusion criteria. The median age of affected patients was 6.6 years, whereas median body condition score was 7/9. The most common clinical signs were coughing (n = 20) and stertor (n = 5). In 27 of 28 cases, a concurrent or previously diagnosed cardiopulmonary disorder was detected. The most common concurrent disease processes were mainstem bronchi collapse (n = 18), tracheal collapse (n = 17), and brachycephalic airway syndrome (n = 8). Fluoroscopy identified complete pharyngeal collapse in 20 of 28 dogs.

Conclusions

Pharyngeal collapse is a complex disease process that likely is secondary to long‐term negative pressure gradients and anatomic and functional abnormalities. Based on the findings of this study, pharyngeal fluoroscopy may be useful diagnostic test in patients with suspected tracheal and mainstem bronchial collapse to identify concurrent pharyngeal collapse.
Skeletal Muscle Vascular Function: A Counterbalance of Insulin Action
Authors: Mahmoud Abeer M. , Brown Michael D. , Phillips Shane A. , Haus Jacob M.
Published: April 2015

Insulin is a vasoactive hormone that regulates vascular homeostasis by maintaining balance of endothelial‐derived NO and ET‐1. Although there is general agreement that insulin resistance and the associated hyperinsulinemia disturb this balance, the vascular consequences for hyperinsulinemia in isolation from insulin resistance are still unclear. Presently, there is no simple answer for this question, especially in a background of mixed reports examining the effects of experimental hyperinsulinemia on endothelial‐mediated vasodilation. Understanding the mechanisms by which hyperinsulinemia induces vascular dysfunction is essential in advancing treatment and prevention of insulin resistance‐related vascular complications. Thus, we review literature addressing the effects of hyperinsulinemia on vascular function. Furthermore, we give special attention to the vasoregulatory effects of hyperinsulinemia on skeletal muscle, the largest insulin‐dependent organ in the body. This review also characterizes the differential vascular effects of hyperinsulinemia on large conduit vessels versus small resistance microvessels and the effects of metabolic variables in an effort to unravel potential sources of discrepancies in the literature. At the cellular level, we provide an overview of insulin signaling events governing vascular tone. Finally, we hypothesize a role for hyperinsulinemia and insulin resistance in the development of CVD.
Fundamental Properties and the Laws of Nature
Authors: Demarest Heather
Published: April 2015

Fundamental properties and the laws of nature go hand in hand: mass and gravitation, charge and electromagnetism, spin and quantum mechanics. So, it is unsurprising that one's account of fundamental properties affects one's view of the laws of nature and vice versa. In this essay, I will survey a variety of recent attempts to provide a joint account of the fundamental properties and the laws of nature. Many of these accounts are new and unexplored. Some of them posit surprising entities, such as counterfacts. Other accounts posit surprising laws of nature, such as instantaneous laws that constrain the initial configuration of particles. These exciting developments challenge our assumptions about our basic ontology and provide fertile ground for further exploration.
Houses on Wheels: National Attachment, Belonging, and Cosmopolitanism in Narratives of Transnational Professionals
Authors: Erkmen T. Deniz
Published: April 2015

This article contributes to discussions on the relationship between national attachments and cosmopolitanization by unpacking the meanings of national attachments and post‐national identifications in the case of transnational professionals, focusing on narratives of professionals embedded in transnational business networks in two locations; Istanbul and New York City. Using in‐depth interviews, the article argues that in the case of transnational professionals one can talk about ‘rooted’ cosmopolitanism in two senses: first, underlining the continuing role of national attachments as roots; and second, pointing to a process in which the post‐national identity is derived from specific experiences in multiple locations, grounding the respondents in their fluid lives. It is through mobility that the respondents develop a sense of belonging – not in spite of it.
The O‐methyltransferase gene MdoOMT1 is required for biosynthesis of methylated phenylpropenes in ripe apple fruit
Authors: Yauk Yar‐Khing , Chagné David , Tomes Sumathi , Matich Adam J. , Wang Mindy Y. , Chen Xiuyin , Maddumage Ratnasiri , Hunt Martin B. , Rowan Daryl D. , Atkinson Ross G.
Published: April 2015

Phenylpropenes, such as eugenol and trans‐anethole, are important aromatic compounds that determine flavour and aroma in many herbs and spices. Some apple varieties produce fruit with a highly desirable spicy/aromatic flavour that has been attributed to the production of estragole, a methylated phenylpropene. To elucidate the molecular basis for estragole production and its contribution to ripe apple flavour and aroma we characterised a segregating population from a Royal Gala (RG, estragole producer) × Granny Smith (GS, non‐producer) apple cross. Two quantitative trait loci (QTLs; accounting for 9.2 and 24.8% of the variation) on linkage group (LG) 1 and LG2 were identified that co‐located with seven candidate genes for phenylpropene O‐methyltransferases (MdoOMT1–7). Of these genes, only expression of MdoOMT1 on LG1 increased strongly with ethylene and could be correlated with increasing estragole production in ripening RG fruit. Transient over‐expression in tobacco showed that MdoOMT1 utilised a range of phenylpropene substrates and catalysed the conversion of chavicol to estragole. Royal Gala carried two alleles (MdoOMT1a, MdoOMT1b) whilst GS appeared to be homozygous for MdoOMT1b. MdoOMT1a showed a higher affinity and catalytic efficiency towards chavicol than MdoOMT1b, which could account for the phenotypic variation at the LG1 QTL. Multiple transgenic RG lines with reduced MdoOMT1 expression produced lower levels of methylated phenylpropenes, including estragole and methyleugenol. Differences in fruit aroma could be perceived in these fruit, compared with controls, by sensory analysis. Together these results indicate that MdoOMT1 is required for the production of methylated phenylpropenes in apple and that phenylpropenes including estragole may contribute to ripe apple fruit aroma.
Phytotoxic and antiphytopathogenic compounds from Thai Alpinia galanga (L.) Willd. rhizomes
Authors: Mongkol Rachsawan , Chavasiri Warinthorn , Ishida Miki , Matsuda Kazuhiko , Morimoto Masanori
Published: April 2015

The management of weeds and diseases that are caused by phytopathogenic fungi is important for preventing the loss of agricultural products. The aim of the present study was to identify phytotoxic and antiphytopathogenic agents from the Thai Alpinia galanga rhizome. Extracts of the dried rhizomes of A. galanga (Zingiberaceae) were separated and tested for phytotoxic activity against lettuce (Lactuca sativa L. cv. Great Lakes) and Italian ryegrass (Lolium multiflorum Lam. cv. Wasefudou) and for antiphytopathogenic activity against Alternaria porri, Colletotrichum gloeosporioides, Fusarium oxysporum and Phytophthora nicotianae. 1′‐Acetoxychavicol acetate (1) was identified as one of the main components, together with trans‐p‐coumaryl acetate (3) and trans‐p‐acetoxycinnamyl acetate (2). 1′‐Acetoxychavicol acetate (1) was solvolyzed with 2% EtOH to yield trans‐p‐coumaryl ethyl ether (6), trans‐p‐coumaryl acetate (3) and trans‐p‐coumaryl alcohol (5). 1′‐Acetoxychavicol acetate (1) completely inhibited the root growth of the lettuce seedlings at 50 μg mL–1, but had a weaker inhibitory effect on the growth of Italian ryegrass. 1′‐Acetoxychavicol acetate also inhibited the growth of P. nicotianae and A. porri, with minimum inhibition concentration values of 15.6 and 31.5 μg mL–1, respectively. The plant growth‐inhibitory activity and fungal growth‐inhibitory activity of trans‐p‐coumaryl acetate (3), trans‐p‐coumaryl ethyl ether, trans‐p‐coumaryl alcohol (5) and trans‐p‐acetoxycinnamyl acetate (2) were lower than those of 1′‐acetoxychavicol acetate. A structure–activity relationship suggested that the strong phytotoxic and antiphytopathogenic activity of 1′‐acetoxychavicol acetate relied on the 1′‐acetoxyl group.
Initial Study on Controllable Roofing System to Tailor Building Solar Loads for Increased HVAC Efficiency
Authors: Wolfe Daniel M. , Goossen Keith W.
Published: April 2015

Space heating and cooling account for a significant percentage of a building's overall energy usage profile. The construction of a building's envelope is an essential component that impacts the overall heating and cooling load. For many years, flat roofs were covered with low albedo materials such as asphalt or modified bitumen, which can reach temperatures of 60 °C–80 °C during summer months. More recently, alternative technologies, such as “white roofs,” have been put forth to mitigate the problem of unwanted thermal gain. However, these traditional roofing materials and recent innovations are passive structures and only promote seasonal benefits. This paper proposes and demonstrates the concept of a controllable reflectance roofing system that can tailor solar loads to desired heating or cooling, significantly reducing overall space heating and cooling energy requirements and costs.
Static and Cyclic Mechanical Loading of Mesenchymal Stem Cells on Elastomeric, Electrospun Polyurethane Meshes
Authors: Cardwell Robyn D. , Kluge Jonathan A. , Thayer Patrick S. , Guelcher Scott A. , Dahlgren Linda A. , Kaplan David L. , Goldstein Aaron S.
Published: April 2015

Biomaterial substrates composed of semi-aligned electrospun fibers are attractive supports for the regeneration of connective tissues because the fibers are durable under cyclic tensile loads and can guide cell adhesion, orientation, and gene expression. Previous studies on supported electrospun substrates have shown that both fiber diameter and mechanical deformation can independently influence cell morphology and gene expression. However, no studies have examined the effect of mechanical deformation and fiber diameter on unsupported meshes. Semi-aligned large (1.75 μm) and small (0.60 μm) diameter fiber meshes were prepared from degradable elastomeric poly(esterurethane urea) (PEUUR) meshes and characterized by tensile testing and scanning electron microscopy (SEM). Next, unsupported meshes were aligned between custom grips (with the stretch axis oriented parallel to axis of fiber alignment), seeded with C3H10T1/2 cells, and subjected to a static load (50 mN, adjusted daily), a cyclic load (4% strain at 0.25 Hz for 30 min, followed by a static tensile loading of 50 mN, daily), or no load. After 3 days of mechanical stimulation, confocal imaging was used to characterize cell shape, while measurements of deoxyribonucleic acid (DNA) content and messenger ribonucleic acid (mRNA) expression were used to characterize cell retention on unsupported meshes and expression of the connective tissue phenotype. Mechanical testing confirmed that these materials deform elastically to at least 10%. Cells adhered to unsupported meshes under all conditions and aligned with the direction of fiber orientation. Application of static and cyclic loads increased cell alignment. Cell density and mRNA expression of connective tissue proteins were not statistically different between experimental groups. However, on large diameter fiber meshes, static loading slightly elevated tenomodulin expression relative to the no load group, and tenascin-C and tenomodulin expression relative to the cyclic load group. These results demonstrate the feasibility of maintaining cell adhesion and alignment on semi-aligned fibrous elastomeric substrates under different mechanical conditions. The study confirms that cell morphology is sensitive to the mechanical environment and suggests that expression of select connective tissue genes may be enhanced on large diameter fiber meshes under static tensile loads.
Optimization of the Idling and Acceleration Characteristics of a Vehicular Gas Turbine by Analog Simulation
Authors: Klarhoefer C.
Published: April 2015

For simulating the performance of a two-shaft regenerative gas turbine with variable nozzles on the power turbine, a mathematical model for the whole system engine-control unit-vehicle was programmed on an analog computer. This paper reports on a study carried out to discover the extent to which the acceleration of the car is influenced by the following parameters: (a) Idle speed of gas generator; (b) Power consumption of auxiliary units; (c) Transmission with a hydrokinetic torque converter; (d) Time constants of temperature gauge and fuel metering system; (e) Variation of nozzle opening during acceleration; (f) Ambient conditions.
The Effect of Inducer Shape on the Performance of High Pressure Ratio Centrifugal Compressors
Authors: Bhinder F. S. , Ingham D. R.
Published: April 2015

Three radial flow impellers, having different inducer blade shapes were designed, manufactured and tested. The inducer section of the impeller was changed in accordance with circular, parabolic and elliptical arc forms, but the meridional profile and the inducer blade inlet angle remained the same. The impellers were tested under nominally identical conditions covering top velocities up to 562 m/s (1844 ft/s). The performance characteristics are given and compared for all three impellers.
A Comparison of Analog, Digital and Hybrid Computing Techniques for Simulation of Gas Turbine Performance
Authors: MacIsaac B. D. , Saravanamuttoo H. I. H.
Published: April 2015

Simulation of gas turbine dynamic performance can be accomplished using analog, digital or hybrid computing techniques. The paper discusses computing techniques for each type of computer and reviews their advantages and disadvantages. It is concluded that the three types of simulation are complementary to each other and that all three computers have their place: the analog is essential for real time simulation of complex engines, the digital is most suitable for detailed studies and the hybrid combines the ease of integration of the analog with the logic and stored program capability of the digital.
A Laser Dual-Beam Method for Flow Measurements in Turbomachines
Authors: Schodl R.
Published: April 2015

Similar to the Doppler technique the principle of this method is also based on light scattered by small particles as they are normally contained in every fluid. Two light beams (laser beams are not necessary) are focused in two very small light spots in the measuring volume. Particles passing both the spots emit two light pulses which can be detected by a photomultiplier. From the time interval between these two pulses and from the known spots distance the flow velocity can be calculated. A statistical analysis of many signals, taken at the same treasuring point, allows calculation of the mean velocity, the mean flow angle and the turbulence degree of the velocity components in a plane normal to the beam axis. Due to the light intensity of the light spots (102 to 103 times higher than the intensity in a Doppler probe volume under similar conditions) a sufficient signal-to-noise ratio is achieved so that velocity measurements even in unseeded air flows are possible up to 500 m/s in backscattering by using a 5 mW laser. Tests were carried out in a supersonic wind tunnel up to a Mach number of 2.2. For measurements in the rotor blade channels of turbomachines a specific trigger optic has been installed.
100s and 1000s Mw Open and Semi-Closed Cycle Gas Turbines for Base and Peak Operation
Authors: Uvarov V. V. , Beknev V. S. , Manushin E. A.
Published: April 2015

There are two different approaches to develop the gas turbines for power. One can get some megawatts by simple cycle or by more complex cycle units. Both units require very different levels of turbine inlet temperature and pressure ratio for the same unit capacity. Both approaches are discussed. These two approaches lead to different size and efficiencies of gas turbine units for power. Some features of the designing problems of such units are discussed.
Protective Systems for Gas Turbines in Industry
Authors: Shinn J. N.
Published: April 2015

Modern heavy-duty gas turbine installations employ a comprehensive system of protective circuits to provide needed equipment protection without jeopardizing plant reliability. The design of these circuits and the overall protective system philosophy are discussed to illustrate how protection and reliability are maximized. Experience gained to date on the application of these protective circuits also is reviewed.
Design and Experimental Studies of Turbine Cooling
Authors: Hiroki Tsuyoshi , Katsumata Ichiro
Published: April 2015

Several problem areas associated with air-cooling of small turbine blades and vanes are identified. These problem areas include the leading edge cooling by film and impingement cooling, comparison of several configurations for trailing edge cooling, effects of Mach number on blade surface heat transfer, effects of film cooling on the aerodynamic performances of turbine cascades, the method of data correlation for the application of heat transfer data taken with low temperature, low pressure rig tests to high temperature, high pressure conditions. Experimental data are presented for each discussed area. The description of design and experimental data of one of the experimental cooled blades and vanes are presented.
Fuel Economy Study of Future Metallic and Ceramic Automotive Gas Turbines
Authors: Walzer P. , Klarhoefer Ch. , Köhler M.
Published: April 2015

An analog simulation technique is described which can calculate the behavior of a gas turbine engine and a gas turbine automobile in steady and unsteady operating conditions. The simulation results agreed well with values measured for a research gas turbine. Possible improvements to the components of a future metallic and a ceramic power plant are discussed. The metallic engine could be developed with today’s technology, but the high temperatures proposed for the ceramic gas turbine could be utilized only after the successful development of the appropriate ceramic components. For a 1550-kg automobile, the simulation technique predicts a fuel economy of 14.7 mpg in the FDC and 24.8 mpg in the EPA highway cycle for the metallic engine. For the ceramic gas turbine, the values are 19.1 mpg in the FDC and 28.2 mpg in the EPA highway cycle. Thus, the metallic gas turbine gives a fuel economy approximately comparable to a present Otto engine automobile, and the ceramic gas turbine could give almost 20 percent better values.
A Review of Specifications for Methods of Measuring Emissions of Air Pollutants and Effluent of Water Pollutants
Authors: Dibelius N. R.
Published: April 2015

The measurement of air pollutants emitted to the atmosphere in exhaust gases from stationary gas turbines must be made in accordance with applicable government specifications in those cases where the measurements are being made to determine compliance with regulations. This paper reviews the methods for measuring opacity, sulfur dioxide, oxides of nitrogen, carbon monoxide, carbon dioxide, oxygen, hydrocarbons, and particulates. In addition, the paper references the Federal Register (volume, number, and page) in which the official specification appears. Other methods, including ASME, SAE, and ASTM, are listed where applicable.
A Simple Variable-Geometry Combustor for the Automotive-Turbine Engine
Authors: Schirmer R. M.
Published: April 2015

A combustor utilizing concepts of swirling flow and orifices in order to optimize mixing rates was developed for application in low-emissions automotive gas turbine engines. Low emissions were obtained at one operating condition with a fixed-geometry configuration. Addition of a variable opening in the dome of the combustor provided low emissions over the expected operating range for an automotive gas turbine engine. Emissions of NOx obtained on a simulated Federal driving cycle were near the Federal statutory limit, and emissions of CO and HC were considerably lower.
Advanced Low NOx Combustors for Supersonic High-Altitude Aircraft Gas Turbines
Authors: Roberts P. B. , Shekleton J. R. , White D. J. , Butze H. F.
Published: April 2015

In recent years, the role of oxides of nitrogen (NOX) within the overall production mechanism of photochemical smog has been recognized, if not completely understood, and in consequence, these oxides are currently considered as serious, immediate, environmental pollutants.
Reaction Rate Determination and Correction for Finite Quenching Rate in Shock Induced Pyrolysis of Methane via a Simple Shock Tube
Authors: Hall J. , Herrin J.
Published: April 2015

Ambiguity in the literature concerning the reaction mechanism of methane pyrolysis still exists, particularly at temperatures below 2100 K. The kinetic results obtained in earlier investigations, in which the reaction progress was followed by direct chemical sampling of the products, subsequent to the reaction, are nearly an order of magnitude larger than those obtained in a more recent study in which the reaction progress was followed by optical methods. In this study, the feasibility of using a simple shock tube, without modifications to enhance the quenching rate, is explored. Such a simple shock tube is used to study the pyrolysis of methane. The rate constant for methane pyrolysis obtained in this study approaches the value reported in an earlier optical study for temperatures above 1750 K. However, the results are subject to considerable scatter. Possible explanations for this scatter are given. Finally, a method is developed to correct the rate constant determinations for any finite-quenching-rate error. This correction, applied to data of this study, resulted in a decrease in the rate constant, bringing it closer to the result of the optical study.
Approximately Calculating Optimum Pressure Ratios for Various Gas Turbine Cycles
Authors: Ushiyama I. J. , Matsumoto N.
Published: April 2015

In designing the gas turbine engine, it is important to know the rough relationship between the specific output, thermal efficiency, and pressure ratios before setting about calculating the practical cycle. In general, the specific output and the thermal efficiency have their maximum values at certain pressure ratios. The pressure ratios for these maximum values, however, differ in the case of the specific output from the thermal efficiency even in the same type of gas turbine. This paper presents the equations for the optimum pressure ratios of the specific output and thermal efficiency which are obtained for seven types of single-shaft gas turbines. Furthermore, a change in the forms of the curves is made clear by the numerical calculations for the specific output and thermal efficiency near the range of optimum pressure ratios. From the results of this paper, the optimum pressure ratios for every type of single-shaft gas turbine can be easily determined from the thermodynamical point of view.
Improved Specific Fuel Consumption of Open Cycle Gas Turbines by Utilization of Waste Heat
Authors: Balukjian H. , Gatzoulis J.
Published: April 2015

Because of the recent sharp rise in fuel costs, the U. S. Navy is re-emphasizing methods to reduce the specific fuel consumption of gas turbine powered ships to be introduced in future designs. This paper presents the results of a study in which the specific fuel consumption (SFC) of open cycle gas turbines was reduced by two alternate methods of utilizing the waste heat: (a) generation of steam for combined gas and steam turbine power (COGAS) from an existing engine design, and (b) incorporation of a recuperator for a new engine design.
Gas Turbine Air Filtration: A Means of Sulfidation Control
Authors: Labadie P. , Boutzale W.
Published: April 2015

This paper documents the relationship between increasing levels of air filtration and decreasing sulfidation corrosion over a 6-year period for a 17-MW gas turbine located adjacent to a dry lake in the Mojave Desert. The machine was subjected to high ambient dust concentrations, rich in sodium chloride and sulfate, which initially produced catastrophic sulfidation. A procedure for the selection of adequate air filtration is presented based on air sampling data and known filter properties.
The Redundant Omega Clutch: A Marine Propulsion Clutch for Turbines
Authors: Aschauer G.
Published: April 2015

The Redundant Omega Clutch is an output shaft-driven centrifugal clutch with an inbuilt hydraulic governor. The clutch is designed with a backup engaging system that provides two separated engaging systems to assure clutch plate clamp. Centrifugal thrust in the engaging cylinders alone is sufficient to maintain clutch engagement for a period of time in the unlikely event of loss of clutch apply pressure from both systems. The clutch has capability to maintain a selected output speed independent of input speed variations and to accept continuous slip heat energy. This paper deals with the design of the clutch and its control system, the principles of operation, performance characteristics, and testing results.
Noise Technology Requirements for Future Aircraft Powerplants
Authors: Kester J. D. , Peracchio A. A.
Published: April 2015

Noise technology requirements are surveyed for several future aircraft powerplants. The applications considered range from growth verions of current production engines to future advanced supersonic transport applications. Although a variety of complex and challenging noise-suppression problems are identified, a sampling of several basic problems common to a variety of engine designs are discussed in more detail. Among these are: the prediction of fan noise generation and propagation in treated ducts, the use of mixer nozzles to reduce jet exhaust noise, and the prediction and absorption of combustion noise. Discussed in the paper are analytical and experimental approaches applicable to solving these problems.
Measurement of Exhaust Emissions From Two J-58 Engines at Simulated Supersonic Cruise Flight Conditions
Authors: Holdeman J. D.
Published: April 2015

Emissions of total oxides of nitrogen, unburned hydrocarbons, carbon monoxide, and carbon dioxide from two J-58 afterburning turbojet engines at simulated high-altitude flight conditions are reported. Test conditions included flight speeds from Mach 2 to 3 at altitudes from 16 to 23 km. For each flight condition, exhaust measurements were made for four or five power levels from maximum power without afterburning through maximum afterburning. The data show that exhaust emissions vary with flight speed, altitude, power level, and radial position across the exhaust. Oxides of nitrogen (NOx) emissions decreased with increasing altitude and increased with increasing flight speed. NOx emission indices with afterburning were less than half the value without afterburning. Carbon monoxide and hydrocarbon emissions increased with increasing altitude and decreased with increasing flight speed. Emissions of these species were substantially higher with afterburning than without.
Heat Transfer With Film Cooling Within and Downstream of One to Four Rows of Normal Injection Holes
Authors: Metzger D. E. , Kuenstler P. A. , Takeuchi D. I.
Published: April 2015

Results are presented from experimental measurements of heat-transfer rates on surfaces which are cooled by injection through one to four rows of evenly spaced, flush, normal injection holes arranged in staggered and in-line patterns with hole spacings of 4.8 dia. Film cooling performanc is evaluated in both the injection and downstream recovery regions from transient tests which provide a uniform wall temperature boundary condition. Both the film and mainstream fluids are air, and film-to-mainstream mass velocity ratios of 0.1, 0.2, 0.3, and 0.5 are covered.