bluuebunny/crossref_metadata_2025 huggingface dataset:
Quantifying group size in the red fox: impacts of definition, season and intrusion by non‐residents
Authors: Dorning J. , Harris S.
Published: January 2019

Determining group membership is fundamental to studies of social behaviour and monitoring population changes. However, this can be challenging for ecologically important solitary‐foraging carnivores such as red foxes, which have flexible social systems. We used camera‐traps to quantify seasonal changes in rates of territory intrusion by non‐residents and compared group definitions based on shared space use (spatial overlap) and social encounters (spatiotemporal overlap). Group sizes based on spatial overlap were overestimated but incorporating a minimum number of sightings (sighting threshold) improved accuracy. Groups defined by spatiotemporal overlap were similar in size to those based on spatial overlap with a sighting threshold but included different individuals, highlighting the challenges of determining group membership. Groups were smallest in spring and summer and largest in autumn and winter because all definitions failed to exclude non‐residents during the mating and dispersal seasons. However, non‐residents were recorded year‐round: over half were known or probable neighbours, and so may be relatives of territory residents. Strangers were most common in winter, when non‐residents were more likely to be males in search of extra‐group copulations. We conclude that groups of territorial, solitary foragers may be defined more accurately by combining patterns of space use, sighting frequency and social connectivity rather than considering these measures in isolation. When social information is not available, spatial overlap measures should include a sighting threshold. Surveying several adjacent territories concurrently helps identify the origins, and motivations, of non‐resident visitors.
Catabolic pathway of arginine in Anabaena involves a novel bifunctional enzyme that produces proline from arginine
Authors: Burnat Mireia , Picossi Silvia , Valladares Ana , Herrero Antonia , Flores Enrique
Published: January 2019

Arginine participates widely in metabolic processes. The heterocyst‐forming cyanobacterium Anabaena catabolizes arginine to produce proline and glutamate, with concomitant release of ammonium, as major products. Analysis of mutant Anabaena strains showed that this catabolic pathway is the product of two genes, agrE (alr4995) and putA (alr0540). The predicted PutA protein is a conventional, bifunctional proline oxidase that produces glutamate from proline. In contrast, AgrE is a hitherto unrecognized enzyme that contains both an N‐terminal α/β propeller domain and a unique C‐terminal domain of previously unidentified function. In vitro analysis of the proteins expressed in Escherichia coli or Anabaena showed arginine dihydrolase activity of the N‐terminal domain and ornithine cyclodeaminase activity of the C‐terminal domain, overall producing proline from arginine. In the diazotrophic filaments of Anabaena, β‐aspartyl‐arginine dipeptide is transferred from the heterocysts to the vegetative cells, where it is cleaved producing aspartate and arginine. Both agrE and putA were found to be expressed at higher levels in vegetative cells than in heterocysts, implying that arginine is catabolized by the AgrE‐PutA pathway mainly in the vegetative cells. Expression in Anabaena of a homolog of the C‐terminal domain of AgrE obtained from Methanococcus maripaludis enabled us to identify an archaeal ornithine cyclodeaminase.
Antifungal activity of selected Malassezia indolic compounds detected in culture
Authors: Gaitanis Georgios , Magiatis Prokopios , Mexia Nikitia , Melliou Eleni , Efstratiou Maria A. , Bassukas Ioannis D. , Velegraki Aristea
Published: January 2019

Background

Malassezia yeasts produce bioactive indolic substances when grown on L‐tryptophan agar. A panel of these substances was tested against commensal and opportunistic fungi, the Minimum Inhibitory Concentration (MIC) was determined and the potential for in loco antifungal activity on the skin was assessed.

Materials and Methods

Eight indoles were included (malassezin, pityriacitrin, indirubin, indolo[3,2‐b]carbazole, 6‐formylindolo[3,2‐b]carbazole, tryptanthrin, 6‐hydroxymethylindolo[3,2‐b]carbazole and 6‐methylindolo[3,2‐b]carbazole) and were tested against 40 fungal strains [yeasts: Malassezia spp.(N = 9); Cryptococcus spp.(N = 10); Candida spp.(N = 7); Yarrowia lipolytica(N = 1); Exophialla dermatitidis (N = 2); moulds: Aspergillus spp.(N = 7); Fusarium spp.(N = 2); Rhizopus oryzae(N = 2)]. The concentration of 5/8 of the tested indoles on diseased skin was calculated from published data. Kruskal‐Wallis and Mann‐Whitney U tests were employed for group susceptibility evaluation in 33 strains.

Results

The MIC range was 0.125‐32 μg/mL, and the median log2MIC was four. Indirubin was the most potent antifungal agent and differed significantly from the others. The highest median MIC was found for FICZ.

Malassezia with Candida strains were more susceptible compared to Cryptococcus and Aspergillus, and this inhibitory activity was predicted to be valid also on human skin.

Conclusions

Malassezia yeasts produce indolic species that inhibit an array of clinically significant yeasts and moulds.
Review: PrP 106‐126 – 25 years after
Authors: Forloni G. , Chiesa R. , Bugiani O. , Salmona M. , Tagliavini F.
Published: January 2019

A quarter of a century ago, we proposed an innovative approach to study the pathogenesis of prion disease, one of the most intriguing biomedical problems that remains unresolved. The synthesis of a peptide homologous to residues 106‐126 of the human prion protein (PrP106‐126), a sequence present in the PrP amyloid protein of Gerstmann–Sträussler–Scheinker syndrome patients, provided a tractable tool for investigating the mechanisms of neurotoxicity. Together with several other discoveries at the beginning of the 1990s, PrP106‐126 contributed to underpin the role of amyloid in the pathogenesis of protein‐misfolding neurodegenerative disorders. Later, the role of oligomers on one hand and of prion‐like spreading of pathology on the other further clarified mechanisms shared by different neurodegenerative conditions. Our original report on PrP106‐126 neurotoxicity also highlighted a role for programmed cell death in CNS diseases. In this review, we analyse the prion research context in which PrP106‐126 first appeared and the advances in our understanding of prion disease pathogenesis and therapeutic perspectives 25 years later.
Heterogeneous Treatment Under Regression Discontinuity Design: Application to Female High School Enrolment
Authors: Önder Yasi˙n Kürşat , Shamsuddin Mrittika
Published: January 2019

This paper undertakes a regression discontinuity (RD) framework with multiple cutoffs unlike typical RD setting where researchers normalize the score variable and pool all the observations. This paper explores this heterogeneity in the effect of Islamic mayor on female secular high schooling in Turkey using the multiple cutoff RD framework developed in Cattaneo et al. (2016). The presence of many parties in the 1994 municipality election in Turkey means that vote share of the strongest opponent party can vary substantially leading to different cutoffs. Meyersson (2014) finds that Islamic mayors of 1994 promoted female high schooling using a normalized and pooled RD framework, which averages the effect across all the different cutoffs. We extend his work by segregating the effect of Islamic mayor across different opponent party's vote shares. Our results suggest that the positive effect on female secular high school attainment was more pronounced in municipalities where the strongest opponent party was secular than where the opponent was conservative. This heterogeneity can be attributed to a policy change in 1999, which restricted religious high school graduates from entering universities.
On the Sources of the Feldstein–Horioka Puzzle across Time and Frequencies
Authors: Ko Jun‐Hyung , Funashima Yoshito
Published: January 2019

This study quantitatively assesses existing explanations for the Feldstein–Horioka puzzle using time–frequency domain analyses for nine countries for the period 1885–2010. The main findings are summarized as follows. First, large economies (e.g. the United States, Italy) show higher correlations between saving and investment than middle‐sized and small countries do. Second, countries can be grouped into two time‐changing patterns of correlations: inverted U‐shaped and increasing patterns. Third, the fiscal balance seems most related to a positive saving‐investment correlation in many countries. Fourth, a global common factor plays an important role in explaining the Feldstein–Horioka puzzle.
The construction of a queer rhizomatic hermeneutics through an exploration of Dennis Cooper'sHTMLnovels
Authors: Barrows Cameron
Published: January 2019

Dennis Cooper's latest project, a series ofHTMLnovels composed entirely ofGIFs,Zac's Haunted Housepublished by Kiddiepunk, showcases the changing literary times and styles. As literature and the Internet become further integrated, our hermeneutical theory and praxis of style must change as well. The influence of the Internet upon the written word is irreversible and has ushered in paradigmatic change. The central question of classical hermeneutics, the relations between writing and the word, and the word to the event has become obfuscated in our digital age. Cooper'sHTMLnovels explicitly play with questions of digital hermeneutics pushing the horizons and perhaps calling for a queer rhizomatic hermeneutics of style. Through his emphasis on structure over narrative, Cooper develops a phenomenology of the digital. Cooper'sHTMLnovel forces the reader to engage in a rhizomatic hermeneutics of the imaginary, that is to say, one must allow the text to develop into multiplicities of worlds, then enter and explore those multiplicities with all the paradoxes and syntheses inherent in them. Cooper's new texts not only question the limits of reading, but also question our hermeneutical methodology and analyses, thus prompting reinterpretation of our understanding of style and its hermeneutical and rhizomatic conceptualizations.
The role of social structure for governing natural resources in decentralized political systems: Insights from governing a fishery in Indonesia
Authors: Gorris Philipp , Glaser Marion , Idrus Rijal , Yusuf Andi
Published: January 2019

This empirical research investigates whether distinct network configurations between actors facilitate or impede successful local natural resource governance in decentralized political systems. Network analysis is applied to disentangle the interaction between actors involved in a decentralized fishery governance system in Indonesia from a polycentric perspective. Using an embedded network case study design, the study examines whether common interaction patterns are observed in local study sites with more successful governance outcomes compared to study sites with less successful outcomes. Three common patterns are identified: (i) higher frequency of interaction of local actors, and (ii) stronger activity of local non‐governmental actors in the polycentric governance network are found in the sites with more successful outcomes. Furthermore, the results show (iii) a higher centralization of the local governance networks with rent‐seeking actors in strong brokerage positions where highly unsustainable resource use prevails. This points to the existence of a ‘dark side’ of brokerage.
Outcome of a High‐Frequency Transcutaneous Electrical Nerve Stimulator (hfTENS) Device for Low Back Pain: A Randomized Controlled Trial
Authors: Jamison Robert N. , Wan Limeng , Edwards Robert R. , Mei Anna , Ross Edgar L.
Published: January 2019

Objective

This controlled trial examined the benefit of a high‐frequency transcutaneous electrical nerve stimulation (hfTENS) device (the Quell, NeuroMetrix, Inc., Waltham, MA, U.S.A.) for patients with chronic low back pain (CLBP).

Methods

Thirty‐five (n = 35) participants were randomly assigned to use the device each day for 3 months (experimental group) and were compared with 33 subjects without the device (treatment‐as‐usual control group). All patients were instructed to complete baseline questionnaires and were assessed on thresholds of pressure pain and mechanical temporal summation as part of standardized quantitative sensory testing (QST). The subjects also uploaded smartphone applications (apps) for tracking use of the hfTENS and for daily pain assessment. Each participant completed weekly phone interviews, was prompted to complete daily pain app assessments, and was asked to repeat the baseline questionnaires again after 6 weeks and 3 months.

Results

Sixty percent of the subjects were female, 77.9% were Caucasian, and the average age was 46.2 years. Significant reductions in pain intensity (P < 0.01) and activity interference (P < 0.025) and significant improvements in pain catastrophizing (P < 0.025) were noted in the experimental group compared with the control group. No group differences were found on depression, anxiety, or pain‐related disability. Older subjects with a longer duration of pain tended to use the hfTENS more often. Subjects who showed greater sensitivity based on QST results revealed increased use of the hfTENS (P < 0.025) and tended to believe that the hfTENS was more helpful in reducing their back pain, but these findings did not reach significance (P = 0.09).

Conclusion

These results suggest that hfTENS can have a moderate effect in reducing pain and improving quality of life in low back pain patients. Further trials designed to determine the mechanism of action of the hfTENS are needed.
Global cognitive performance is associated with sleep efficiency measured by polysomnography in patients with Parkinson's disease
Authors: Sobreira Emmanuelle S. T. , Sobreira‐Neto Manoel A. , Pena‐Pereira Márcio A. , Chagas Marcos H. N. , Fernandes Regina M. F. , Eckeli Alan L. , Tumas Vitor
Published: January 2019

Aim

Sleep disorders can be associated with an increased risk for cognitive decline in patients with Parkinson's disease (PD). The aim of this study was to examine the association between cognitive status and presence of sleep symptoms and sleep disorders in PD patients.

Methods

We evaluated excessive sleepiness, other sleep symptoms, and performed polysomnography and neuropsychological evaluation in 79 patients. They were classified as having normal cognition (PDNC), mild cognitive impairment (PDMCI), or dementia (PDD).

Results

There were 29 PDNC, 39 PDMCI, and 11 PDD patients. PDD patients were older, had higher scores on the Unified Parkinson's Disease Rating Scale, and lower Schwab and England Activities of Daily Living scores than PDNC patients. After analysis of the polysomnographic variables, it was also found that PDD patients had a lower sleep efficiency, lower total sleep time, and lower number of sleep state changes than PDNC patients. In a stepwise analysis, defining Mattis Dementia Rating Scale scores as the dependent variable, the results were a model that selected three variables that accounted for 59% of the variation in the Mattis Dementia Rating Scale score: wake time after sleep onset, number of state changes, and schooling.

Conclusion

We found a significant association between global cognitive performance and wake time after sleep onset and the number of state changes during sleep measured in the polysomnography of PD patients. However, we did not find any other association between sleep disorders or symptoms and cognitive status or cognitive performance of PD patients.
Highly Sensitive and Selective Fluorescence Probe for 2,4‐Dinitrophenylhydrazine Detection in Wastewater Using Water‐Soluble CdTe QDs
Authors: Wang Qiuyue , Wang Xuehan , Wu Yiwei
Published: January 2019

A simple, cheap, sensitive and selective probe for determination of DNPH in wastewater using thioglycolic acid (TGA)‐coated CdTe QDs (TGA‐QDs) as fluorescence probe has been established, and the properties of CdTe QDs were characterized by TEM, FT‐IR, DLS, XRD and zeta potentials. CdTe QDs fluorescence is highly efficiently quenched after adding DNPH on account of electron transfer effect, and the fluorescence quenching behavior of CdTe QDs interaction with DNPH is static quenching process. A good linear relationship is observed between the relative fluorescence intensity (F0/F) and 0.06–10 ng mL−1 of DNPH. As compared with some of reported methods, LOD of this method for analysis of DNPH (0.23 ng mL−1) is the lowest. Masking agents of DDTC and NH4OH can eliminate the interference of Cu2+, Ag+ and Hg2+. Hence, DNPH can be selectively and accurately detected and the established method was successfully used for detecting DNPH in wastewater with acceptable recovery of 90.6–102%.
Photoprotective and Antigenotoxic Effects of the Flavonoids Apigenin, Naringenin and Pinocembrin
Authors: García Forero Adriana , Villamizar Mantilla Diego Armando , Núñez Luis A. , Ocazionez Raquel Elvira , Stashenko Elena E. , Fuentes Jorge Luis
Published: January 2019

This work evaluated the photoprotective and antigenotoxic effects against ultraviolet B (UVB) radiation of flavonoid compounds apigenin, naringenin and pinocembrin. The photoprotective efficacy of these compounds was estimated using in vitro photoprotection indices, and the antigenotoxicity against UVB radiation was evaluated using the SOS chromotest and an enzymatic (proteinase K/T4 endonuclease V enzyme) comet assay in UV‐treated Escherichia coli and human (HEK‐293) cells, respectively. Naringenin and pinocembrin showed maximum UV‐absorption peak in UVC and UVB zones, while apigenin showed UV‐absorption capability from UVC to UVA range. These compounds acted as UV filters reducing UV‐induced genotoxicity, both in bacteria and in human cells. The enzymatic comet assay resulted highly sensitive for detection of UVB‐induced DNA damage in HEK‐293 cells. In this work, the photoprotective potential of these flavonoids was widely discussed.
Carbonate drifts as marine archives of aeolian dust (Santaren Channel, Bahamas)
Authors: Lindhorst Sebastian , Betzler Christian , Wunsch Marco , Lüdmann Thomas , Kuhn Gerhard
Published: January 2019

Sediment data from the Bahamian Santaren carbonate drift reveal the variability of trans‐Atlantic Saharan dust transport back to about 100 ka bp (Marine Isotope Stage 5·3) and demonstrate that carbonate drifts are a valuable pelagic archive of aeolian dust flux. Carbonate drift bodies are common around tropical carbonate platforms; they represent large‐scale accumulations of ocean‐current transported material, which originates from the adjacent shallow‐water carbonate factory as well as from pelagic production, i.e. periplatform ooze. Subordinately, there is a clay‐size to silt‐size non‐carbonate fraction, which typically amounts to less than 10% of the sediment volume and originates from aeolian and fluvial input. Sedimentation rates in the 5·42 m long core GeoHH‐M95‐524 recovered 25 km west of Great Bahama Bank in the Santaren Channel ranges from 1·5 to 24·5 cm ka−1 with lowest values during the last glacial lowstand and highest values following platform re‐flooding around 8 ka bp. These sedimentation rates imply that carbonate drifts have not only the potential to resolve long‐term environmental changes on orbital timescales, but also millennial to centennial fluctuations during interglacials. The sediment core has been investigated with the aim of characterizing the lithogenic dust fraction. Laboratory analyses included X‐ray fluorescence core scanning, determination of carbonate content and grain‐size analyses (of bulk and terrigenous fraction), as well as visual inspections of the lithogenic residue; the age model is based on oxygen isotopes and radiocarbon ages. Data show that the input of aeolian dust in the periplatform ooze as indicated by Ti/Al and Fe/Al element ratios abruptly increases at 57 ka bp, stays elevated during glacial times, and reaches a Holocene minimum around 6·5 ka bp, contemporary to the African Humid Period. Subsequently, there is a gradual increase in dust flux which almost reaches glacial levels during the last centuries. Grain‐size data show that the majority of dust particles fall into the fine silt range (below 10 μm); however, there is a pronounced coarse dust fraction in the size range up to 63 μm and individual ‘giant’ dust particles are up to 515 μm in size. Total dust flux and the relative amounts of fine and coarse dust are decoupled. The time‐variable composition of the grain‐size spectrum is interpreted to reflect different dust transport mechanisms: fine dust particles are delivered by the trade winds and the geostrophic winds of the Saharan Air Layer, whereas coarse dust particles travel with convective storm systems. This mode of transport ensures continuous re‐suspension of large particles and results in a prolonged transport. In this context, grain‐size data from the terrigenous fraction of carbonate drifts provide a measure for past coarse dust transport, and consequently for the frequency of convective storm systems over the dust source areas and the tropical Atlantic.
Lacustrine stromatolites: Useful structures for environmental interpretation – an example from the Miocene Ebro Basin
Authors: Martin‐Bello Leticia , Arenas Concha , Jones Brian
Published: January 2019

The significance of stromatolites as depositional environmental indicators and the underlying causes of lamination in the lacustrine realm are poorly understood. Stromatolites in a ca 600 m thick Miocene succession in the Ebro Basin are good candidates to shed light on these issues because they are intimately related to other lacustrine carbonate and sulphate facies, grew under variable environmental conditions and show distinct lamination patterns. These stromatolites are associated with wave‐related, clastic‐carbonate laminated limestones. Both facies consist of calcite and variable amounts of dolomite. Thin planar stromatolites (up to 10 cm thick and less than 6 m long) occurred in very shallow water. These stromatolites represented first biological colonization after: (i) subaerial exposure in the palustrine environment (i.e. at the beginning of deepening cycles); or (ii) erosion due to surge action, then coating very irregular surfaces on laminated limestones (i.e. through shallowing or deepening cycles). Sometimes they are associated with evaporative pumping. Stratiform stromatolites (10 to 30 cm high and tens of metres long) and domed stromatolites (10 to 30 cm high and long) developed in deeper settings, between the surge periods that produced hummocky cross‐stratification and horizontal lamination offshore. Changes in stromatolite lamina shape, and thus in the growth forms through time, can be attributed to changes in water depth, whereas variations in lamina continuity are linked to water energy and sediment supply. Growth of the stromatolites resulted from in situ calcite precipitation and capture of minor amounts of fine‐grained carbonate particles. Based on texture, four types of simple laminae are distinguished. The simple micrite and microsparite laminae can be grouped into light and dark composite laminae, which represent, respectively, high and low Precipitation/Evaporation ratio periods. Different lamination patterns provide new ideas for the interpretation of microbial laminations as a function of variations in climate‐dependent parameters (primarily the Precipitation/Evaporation ratio) over variable timescales.
The role of prediagnostic data in injury epidemiology in preprofessional dancers
Authors: Moita João Paulo , Gomes António , Xarez Luís , Coelho Constança
Published: January 2019

Introduction

preprofessional dance training starts at very early ages, on a highly demanding environment placing students at significant risk for injury. Injury management and prevention are a matter of concern. Given the constant interchangeability of risk factors, identifying injury patterns may prove to be equally as important. Data looking back from the time of injury through context‐specific approaches are missing.

Objectives

To identify activity‐related injury patterns based on prediagnostic data.

Methods

Prospective, non‐randomized, observational study, over a 3 years period on a full‐time preprofessional dance school featuring both gender students aged 9‐21 years old. Non‐parametric statistics were used.

Results

A total of 625 dance injury records from 209 students, n = 68 males and n = 141 females, were analyzed. Season injury risk probability was identified, proving different for each skill level (SkL). Multiple individual injuries revealed a trend toward prevalence rates in advanced level, while index injuries incidence becomes more noticeable in entry level students. Overall incidence rates had no significant differences within SkL. Anatomical location was in line with previous research, although differences were found between gender and SkL. Most injuries occurred in classes, with jumps standing out as the main motor action associated with injury symptoms of gradual onset mechanism.

Conclusion

Dance injuries happen because of dance practice. Knowing the context of injury history from the injured dancer perspective is determinant for management and prevention. prediagnostic data are an umbrella term encompassing several aspects of injury background and represents fertile ground for research. Context‐specific methodological approaches are recommended.
Soil extension needs to be a continuum of learning; soil workshop reflections 10 years on
Authors: Andersson Karl O. , Orgill Susan E.
Published: January 2019

Effective extension of soil research builds landholder capacity to manage soils productively and sustainably. Government‐funded extension programmes also aim to improve the state of the environment through efficient use of resources and mitigating or preventing further land degradation. To these ends, a soil extension programme aimed at farmers in south‐eastern Australia was conducted during 2005–2008. The programme was designed to equip landholders with the knowledge, skills and confidence to diagnose and address soil constraints, as well as compile spatial information on soil properties. The programme involved four workshops that covered agricultural productivity, soil management and potential off‐site impacts. Workshops were held on‐farm and involved discussion, theory supported with practical exercises, and field visits. More than 1,400 participants were provided with subsidized soil tests to encourage soil monitoring and underpin the workshop theory on land capability and soil constraints (e.g., soil acidity, sodicity, salinity, nutrient decline and toxicities). Prior to the course, most participants did not regularly soil test so training on monitoring protocols was provided. The soil data indicated considerable phosphorus deficiencies, low organic carbon levels, and acidity across both cropping and pasture systems. Participant knowledge and land management intentions were tracked throughout the workshop series using surveys. The surveys identified a positive shift in the knowledge, understanding and confidence of most participants. However, a follow‐up survey 10 years later indicated that these changes may not have been broadly sustained. Based on our study, we recommend continued engagement of landholders along a learning pathway to maximize investment in soil extension.
Placement of a balloon for resuscitative endovascular balloon occlusion of the aorta without fluoroscopic guidance in canine cadavers
Authors: Loewen Jennifer Marie , Blume Lauren Melissa , Bach Jonathan Francis
Published: January 2019

Objective

To determine whether a balloon for resuscitative endovascular balloon occlusion of the aorta (REBOA) could be accurately placed in the descending aorta between the left subclavian and celiac arteries (zone I) by using external anatomic landmarks in dogs.

Study design

Cadaver study.

Sample population

Fifteen canine cadavers of 3 weight categories (10–20, 20–30, and ≥ 30 kg).

Methods

Percutaneous catheterization of the femoral artery was attempted under ultrasonographic guidance; when unsuccessful, an arterial cutdown was performed to place an introducer sheath. Distance was measured between the introducer sheath and the target region, located ventral to the epaxial muscles at the level of the 12th thoracic vertebra. The balloon was advanced the measured distance, and placement was confirmed with fluoroscopy. The volume of iohexol solution required to inflate balloons was recorded. Histopathology was performed on the aortas of the first 5 dogs.

Results

Three catheters were placed under ultrasonographic guidance. Balloons were successfully placed into zone I in 15 of 15 cadavers. Balloons were inflated with a median 0.4 mL/kg (range, 0.21–0.67) of iohexol solution. Minor changes were identified in 2 of 5 dogs examined with histopathology (linear defects in 1 dog, small focal dissection in the other).

Conclusion

A balloon for REBOA was consistently placed in the target zone I without fluoroscopic guidance.

Clinical significance

Fluoroscopy may not be required for zone I REBOA in dogs. Additional studies are warranted to evaluate the feasibility of REBOA in clinical dogs with hemoperitoneum.
Comparison of initial leak pressures after single‐ and double‐layer cystotomy closure with barbed and nonbarbed monofilament suture material in an ex vivo ovine model
Authors: Duffy Daniel J. , Kindra Cameron G. , Moore George E.
Published: January 2019

Objective

To compare initial leakage pressure after double‐layer inverting and single‐layer appositional closures with unidirectional barbed suture or an analogous monofilament absorbable suture in an ex vivo ovine model.

Study design

Experimental study.

Sample population

Ovine cadaveric bladders (n = 48).

Methods

A 4‐cm ventral cystotomy was performed in each bladder. Bladders were randomly divided into 4 groups (n = 12 each group) and sutured in an open setting with a single‐layer appositional or a double‐layer inverting pattern of unidirectional 2–0 barbed or an analogous monofilament suture. Intraluminal pressure at initial leakage and leakage location were recorded. Analysis of variance was used to compare initial leak pressure between the 4 groups (P< .05).

Results

Ovine urinary bladders closed with double‐layer inverting closures leaked at intraluminal pressures about twofold greater than bladders closed with single‐layer appositional closures (P< .0001) whether barbed or nonbarbed suture was used (P≥ .987). Bladders most commonly leaked at the suture hole after single‐layer closure. Bladders that had been repaired with a double‐layer closure leaked at the knot in nonbarbed closures or at the preconstructed end loop in barbed closures.

Conclusion

Double‐layer closure increased leakage pressures compared with single‐layer closures, irrespective of the suture type used.

Clinical significance

This study provides evidence to support double‐layer rather than single‐layer closure of cystotomies in clinical cases. The use of barbed suture may be suitable for cystorrhaphy in sheep.
Factors affecting the duration of anesthesia and surgery of canine and feline gonadectomies performed by veterinary students in a year‐long preclinical surgery laboratory
Authors: Shaver Stephanie L. , Larrosa Matias , Hofmeister Erik H.
Published: January 2019

Objective

To determine factors affecting the duration of canine and feline gonadectomies performed by second‐year veterinary students.

Study design

Retrospective study of 1288 gonadectomies.

Sample population

One hundred ninety‐four second‐year veterinary students in a 24‐week veterinary surgical teaching laboratory.

Methods

Surgical and anesthetic records were analyzed and arranged by primary surgeon in chronological order. Species, sex, weight, body condition score, occurrence of an intraoperative complication, and order of sequential cases in the year performed by the primary surgeon were assessed for their influence on anesthesia, surgery, and preparation times.

Results

Each student performed an average of 6.6 (±1.08) gonadectomies over 24 weeks. Dogs, females, increasing weight, intraoperative complications, and earlier sequential cases were associated with longer duration of surgery and anesthesia. These factors accounted for 50% and 59% of anesthetic and surgical time variance, respectively. The rate of intraoperative complications did not change across time but was higher during canine ovariohysterectomies. Duration of anesthesia and surgery for canine orchiectomy decreased by 29 and 21 minutes, respectively, and for canine ovariohysterectomy decreased by 16 and 12 minutes, respectively, over 24 weeks without reaching a learning plateau.

Conclusion

Species, sex, weight, complications, and earlier sequential cases influenced duration of anesthesia and surgery.

Clinical significance

By establishing a baseline for duration of student‐performed surgeries and describing the relative impact of factors influencing duration, students and educators may be able to set goals for student improvement during teaching laboratories.
End Effects on H2-Forced Convection in Rectangular Ducts of Large Aspect Ratios
Authors: Wang C. Y.
Published: January 2019

The H2-forced convection in a rectangular duct of large aspect ratio (>10) is studied. It is found that the short ends have non-negligible effects on the Nusselt number and the temperature distribution. Even at infinite aspect ratios, the Nusselt number depends on the net heat addition from the ends, but not how they are distributed.
Effects of Thermophysical Variable Properties on Liquid-Sodium Convective Flows in a Square Enclosure
Authors: Zamora Blas
Published: January 2019

The influence of the variable properties on the buoyancy-driven flows of liquid sodium established in a square enclosure including two inner heated plates is numerically investigated. Two-dimensional turbulent simulations are obtained, considering uniform wall temperature heating conditions. The low-Reynolds k–ω turbulence model is employed. The average Nusselt number and the dimensionless mass-flow rate evaluated between the inner plates are obtained for a wide range of the Rayleigh number, varying from 103 to 1012. Several practical correlations are presented. The results obtained for different heating intensities are analyzed and compared. The expected decay in the heat transfer coefficients is less relevant than that previously obtained for airflows. The thermal structure of the flow into the enclosure is also shown.
A Closed Form Solution of Dual-Phase Lag Heat Conduction Problem With Time Periodic Boundary Conditions
Authors: Biswas Pranay , Singh Suneet , Bindra Hitesh
Published: January 2019

The Laplace transform (LT) is a widely used methodology for analytical solutions of dual phase lag (DPL) heat conduction problems with consistent DPL boundary conditions (BCs). However, the inversion of LT requires a series summation with large number of terms for reasonably converged solution, thereby, increasing computational cost. In this work, an alternative approach is proposed for this inversion which is valid only for time-periodic BCs. In this approach, an approximate convolution integral is used to get an analytical closed-form solution for sinusoidal BCs (which is obviously free of numerical inversion or series summation). The ease of implementation and simplicity of the proposed alternative LT approach is demonstrated through illustrative examples for different kind of sinusoidal BCs. It is noted that the solution has very small error only during the very short initial transient and is (almost) exact for longer time. Moreover, it is seen from the illustrative examples that for high frequency periodic BCs the Fourier and DPL model give quite different results; however, for low frequency BCs the results are almost identical. For nonsinusoidal periodic function as BCs, Fourier series expansion of the function in time can be obtained and then present approach can be used for each term of the series. An illustrative example with a triangular periodic wave as one of the BC is solved and the error with different number of terms in the expansion is shown. It is observed that quite accurate solutions can be obtained with a fewer number of terms.
Application of Fractional Scaling Analysis for Development and Design of Integral Effects Test Facility
Authors: Dzodzo Milorad B. , Oriolo Francesco , Ambrosini Walter , Ricotti Marco , Grgic Davor , Ferri Roberta , Achilli Andrea , Bianchi Fosco , Meloni Paride
Published: January 2019

The aim of this paper is to present a fractional scaling analysis (FSA) application for a system with interacting components where multiple figures of merits need to be respected during complex transient accident scenario with several consecutive time sequences. This paper presents FSA application to the International Reactor Innovative and Secure (IRIS) reactor and Simulatore Pressurizzato per Esperienze di Sicurezza 3 (SPES3) integral effects test (IET) facility. The FSA was applied for the small break loss of coolant accident (SBLOCA) on the direct vessel injection (DVI) line as the most challenging transient scenario. The FSA methodologies were applied for two figures of merits: (1) reactor and containment vessels pressure responses, and (2) reactor vessel water collapsed level response. The space decomposition was performed first. The reactor vessel and containment vessel were divided in components so that important phenomena and their consequences can be evaluated in each of them. After that, the time decomposition in consecutive time sequences was performed for the considered transient (DVI SBLOCA) based on the starts, or ends, of the defining events. The configuration of the system in each time sequence might be different and dependent on the control system actions connecting, or disconnecting, various components of the system due to the valves openings, or closings. This way, the important phenomena and their consequences can be evaluated for each component and time sequence. Also, this paper presents and discusses options for deriving nondimensional groups and calculation of distortions between prototype and model responses for complex transients containing multiple consecutive time sequences. The input data for scaling analysis are based on the results of RELAP/GOTHIC analysis performed for IRIS and RELAP analysis performed for SPES3. The scaling analysis was applied iteratively several times for different IRIS and SPES3 configurations. Based on the intermediate results, some components in the IRIS and SPES3 were redesigned so that the distortions between IRIS and SPES3 responses are decreased.
Effect of Steam Temperature and Pressure on the Oxidation of Potential Coating Alloy FeCrAl for Supercritical Water-Cooled Reactor Application
Authors: Xiao Bingjie , Huang Xiao , Yang Qi , Patnaik Prakash
Published: January 2019

MCrAl (M = Fe, Ni, or Co) alloys have exceptional corrosion and oxidation resistance and can be used as both oxidation resistant structural materials and coatings. As coatings, they protect high temperature steels or Ni based alloys by forming a dense alumina layer on the surface and thus impeding further oxidation. In order to assess its potential usage as an overlay coating on components used in supercritical water-cooled nuclear reactors (SCWRs), an Fe-2 3Cr-5Al alloy in the form of wire was tested under two different super-heated steam (SHS) conditions (625 °C and 800 °C) and also in supercritical water (SCW) (625 °C and 26 MPa), for 500 h. The corrosion behavior of samples was assessed by measuring the weight change per unit surface area and by examining the surface, cross-sectional microstructure and the phase compositions using scanning electron microscopy (SEM) and X-ray diffraction (XRD). The tested samples showed different oxidation behavior after exposure to these three conditions. SEM and XRD results showed that FeCrAl has the ability to form protective Al- and Cr-containing oxide(s) under all three conditions. Based on the findings, it is concluded that the oxidation behavior of Fe–23Cr–5Al is highly influenced by pressure and temperature within the range of testing conditions. SHS exposure at low temperature led to greater weight gain while that in SCW resulted in weight loss. Overall, its performance is better under SHS conditions compared to CoCrWC S16 but worse under the SCW condition.
Lean-Burn Characteristics of a Heavy-Duty Diesel Engine Retrofitted to Natural-Gas Spark Ignition
Authors: Liu Jinlong , Dumitrescu Cosmin Emil
Published: January 2019

Increased utilization of natural gas (NG) in the transportation sector can decrease the use of petroleum-based fuels and reduced greenhouse gas emissions. Heavy-duty diesel engines retrofitted to NG spark ignition (SI) can achieve higher efficiencies and low NOX, CO, and hydrocarbon (HC) emissions when operated under lean-burn conditions. To investigate the SI lean-burn combustion phenomena in a bowl-in-piston combustion chamber, a conventional heavy-duty direct-injection CI engine was converted to SI operation by replacing the fuel injector with a spark plug and by fumigating NG in the intake manifold. Steady-state engine experiments and numerical simulations were performed at several operating conditions that changed spark timing (ST), engine speed, and mixture equivalence ratio. Results suggested a two-zone NG combustion inside the diesel-like combustion chamber. More frequent and significant late-burn (including double-peak heat release rate) was observed for advanced ST. This was due to the chamber geometry affecting the local flame speed, which resulted in a faster and thicker flame in the bowl but a slower and thinner flame in the squish volume. Good combustion stability (COVIMEP < 3%), moderate rate of pressure-rise, and lack of knocking showed promise for heavy-duty CI engines converted to NG SI operation.
Investigations of the Adhesive Contact Behavior of Elastic Layered Media With Surface Roughness
Authors: Zhang Yuyan , Si Lina , Zhang Xiaoqing , Li Juan , Wang Wanjun
Published: January 2019

A deterministic adhesive model for the contact between an elastic layered medium with surface roughness and a smooth elastic microsphere was developed on the basis of the Lennard–Jones surface force law. Through numerical simulations, the adhesive contact behavior of the layered medium with the measured three-dimensional (3D) surface topography was comparatively analyzed with that of the homogeneous medium. Furthermore, the contact characteristics of the layered medium with pre-assigned roughness parameters were investigated with the aid of a computer-generated technique for simulating surface roughness. Results showed that the pull-off force for the contact problem involving rough surfaces was influenced by the contact location, and the average value for the contact between an alumina (SiO2) microsphere and a diamond-like carbon/silicon (DLC/Si)-layered medium was smaller than that for the contact between a SiO2 microsphere and a Si homogeneous half-space. In addition, the effect of the diamond-like carbon (DLC) layer on reducing adhesion was smaller than that of the surface roughness. Finally, the average pull-off force for a DLC/Si-layered medium with computer-generated surface roughness rapidly decreased; however, it eventually became almost unchangeable with the increase in the root-mean-square (RMS) deviation.
Classification and Modeling of Fluid Dynamic Loss in Aeroengine Transmission Gears
Authors: Arisawa Hidenori , Shinoda Yuji , Tanaka Mitsuaki , Goi Tatsuhiko , Akahori Hirofumi , Yoshitomi Mamoru
Published: January 2019

Reducing the fluid dynamic power loss for increasing speed is critical for the development of highly efficient high-speed aircraft engine gearing. In this study, the fluid dynamic loss was experimentally performed using a precise friction loss management technique along a vacuum being drawn on the gearbox. The experimental fluid dynamic loss could be classified as either “oil jet acceleration loss and oil reacceleration loss based on the conservation law of momentum for a point mass” or “oil churning loss and windage loss based on the conservation law of momentum for an incompressible continuum.” Windage loss and oil dynamic loss (i.e., the summation of oil jet acceleration loss, oil reacceleration loss, and oil churning loss) were modeled to develop equations for a loss prediction. The equations of the windage loss are pressure loss of flow passing through the side clearance of the gears and energy loss caused by the vortex generation in the cavity between tooth valleys. Oil dynamic loss was determined by multiplying the oil jet acceleration loss by an empirical coefficient. The results of the loss prediction equations agree with the experimental results, demonstrating the validity of the proposed model of the fluid dynamic loss.
Hierarchical Multiscale Modeling of Tire–Soil Interaction for Off-Road Mobility Simulation
Authors: Yamashita Hiroki , Chen Guanchu , Ruan Yeefeng , Jayakumar Paramsothy , Sugiyama Hiroyuki
Published: January 2019

A high-fidelity computational terrain dynamics model plays a crucial role in accurate vehicle mobility performance prediction under various maneuvering scenarios on deformable terrain. Although many computational models have been proposed using either finite element (FE) or discrete element (DE) approaches, phenomenological constitutive assumptions in FE soil models make the modeling of complex granular terrain behavior very difficult and DE soil models are computationally intensive, especially when considering a wide range of terrain. To address the limitations of existing deformable terrain models, this paper presents a hierarchical FE–DE multiscale tire–soil interaction simulation capability that can be integrated in the monolithic multibody dynamics solver for high-fidelity off-road mobility simulation using high-performance computing (HPC) techniques. It is demonstrated that computational cost is substantially lowered by the multiscale soil model as compared to the corresponding pure DE model while maintaining the solution accuracy. The multiscale tire–soil interaction model is validated against the soil bin mobility test data under various wheel load and tire inflation pressure conditions, thereby demonstrating the potential of the proposed method for resolving challenging vehicle-terrain interaction problems.
Microfluidic dielectrophoresis illuminates the relationship between microbial cell envelope polarizability and electrochemical activity
Authors: Wang Qianru , Jones A.-Andrew D. , Gralnick Jeffrey A. , Lin Liwei , Buie Cullen R.
Published: January 2019

A microfluidic approach enables quick quantification of electrochemical activity in living bacteria.
Catalyst-free, highly selective synthesis of ammonia from nitrogen and water by a plasma electrolytic system
Authors: Hawtof Ryan , Ghosh Souvik , Guarr Evan , Xu Cheyan , Mohan Sankaran R. , Renner Julie Nicole
Published: January 2019

Lightning in a bottle: Plasma enables selective, electrolytic production of ammonia from nitrogen and water.
Reliable and practical computational description of molecular crystal polymorphs
Authors: Hoja Johannes , Ko Hsin-Yu , Neumann Marcus A. , Car Roberto , DiStasio Robert A. , Tkatchenko Alexandre
Published: January 2019

Quantum-mechanical calculations enable reliable computation of structures and stabilities for molecular crystal polymorphs.
FDISCO: Advanced solvent-based clearing method for imaging whole organs
Authors: Qi Yisong , Yu Tingting , Xu Jianyi , Wan Peng , Ma Yilin , Zhu Jingtan , Li Yusha , Gong Hui , Luo Qingming , Zhu Dan
Published: January 2019

We developed an advanced clearing method with superior fluorescence-preserving capability for 3D imaging of whole organs.
Li substituent tuning of LED phosphors with enhanced efficiency, tunable photoluminescence, and improved thermal stability
Authors: Zhao Ming , Xia Zhiguo , Huang Xiaoxiao , Ning Lixin , Gautier Romain , Molokeev Maxim S. , Zhou Yayun , Chuang Yu-Chun , Zhang Qinyuan , Liu Quanlin , Poeppelmeier Kenneth R.
Published: January 2019

A codoping strategy is advanced to improve luminescence efficiency, emission color tuning, and thermal stability of LED phosphors.