bluuebunny/crossref_metadata_2025 huggingface dataset:
A pre‐LGM sandur at Fiskarheden in NW Dalarna, central Sweden – sedimentology and glaciotectonic deformation
Authors: Flindt Anne‐Cécile , Benediktsson Ívar Örn , Alexanderson Helena , Möller Per
Published: January 2018

The Fiskarheden quarry, situated in NW Dalarna, central Sweden, reveals thick coarse‐grained sediments of Scott type facies association representing a sandur deposited in an ice‐proximal proglacial environment. Optically Stimulated Luminescence (OSL) dating of the sandur sediments suggests a pre‐Last Glacial Maximum (LGM) age. Most acquired ages are pre‐Saalian (>200 ka) and we regard each of these ages to represent non/poorly bleached sediment except for one small‐aliquot OSL age of 98±6 ka. This age comes from the top surface of an arguably well‐bleached sand bed deposited on the lee‐side of a braid‐bar, putting the sandur build‐up into the Early Weichselian. Large‐scale glaciotectonic structures show an imbricate thrust fan involving both ductile and brittle deformation. The deformation was from the WNW, which largely coincides with the formative trend of the predominating streamlined terrain and Rogen moraine tracts surrounding Fiskarheden. It is suggested that the deformation of the sandur sediments took place when the advancing glacier approached and pushed its own proglacial outwash sediment, during an ice‐marginal oscillation either at the inception of one of the Early Weichselian glaciations in the area, or during a general ice retreat amid a deglacial phase. The Fiskarheden sandur deposits are covered by a subglacial traction till deposited from the NE/NNE. This direction corresponds with younger streamlined terrain flowsets cross‐cutting the older NNW–SSE system and probably represents deglaciation in the area following the LGM. This study will add to the understanding of the formation and deformation of Pleistocene sandur successions and their relationship to past ice‐sheet behaviour.
Direct‐acting antiviral regimens are safe and effective in the treatment of hepatitis C in simultaneous liver–kidney transplant recipients
Authors: Nookala Anupama U. , Crismale James , Schiano Thomas , Te Helen , Ahn Joseph , Robertazzi Suzanne , Rodigas Colleen , Satoskar Rohit , KC Mandip , Hassan Mohamed , Smith Coleman
Published: January 2018

Hepatitis C (HCV) remains the single most common etiology of end‐stage liver disease leading to simultaneous liver/kidney transplant (SLKT) and has worse post‐transplant survival compared to non‐HCV patients. We aim to assess the effectiveness and tolerance of the all‐oral direct‐acting antiviral (DAA) agents with or without ribavirin (RBV) in the treatment of HCV recurrence post‐SLKT. Thirty‐four patients were studied retrospectively, composed predominantly of treatment‐naïve (73.5%) non‐Caucasian (61.8%) males (82.4%) infected with genotype 1a (64.7%). 94.1% reached a sustained virologic response (SVR) after 24 weeks (32/34 patients), without difference between 12 and 24 weeks of therapy. 64.7% had no clinical side effects. Three deaths occurred, all unrelated to treatment. One patient had liver rejection; tacrolimus was increased and prednisone was initiated while HCV treatment was continued and the patient ultimately achieved SVR. No liver graft losses. No kidney rejection or losses. We demonstrated that DAA combinations with or without RBV result in a remarkable SVR rate and tolerated in the majority of the studied SLKT patients. It is safe to wait to treat until post–kidney transplant and therefore increase the donor pool for these patients. Our cohort is ethnically diverse, making our results generalizable.
Systolic heart failure after liver transplantation: Incidence, predictors, and outcome
Authors: Sonny Abraham , Govindarajan Srinivasa R. , Jaber Wael A. , Cywinski Jacek B.
Published: January 2018

Although most patients presenting for liver transplantation have normal left ventricular function, some develop left ventricular failure after transplantation. The primary objective of our study was to determine the predictors of systolic heart failure (HF) occurring immediately after liver transplantation. Its etiology, prospects of recovery, and factors associated with nonrecovery were also studied. Liver transplantations performed at our institution from January 2006 to February 2015 were evaluated using prospectively collected institutional registries. Patients with echocardiographically documented decline in ejection fraction to <45% within 6 months after liver transplantation were identified. Four controls were chosen per case: matched for age, gender, transplant year, and model for end‐stage liver disease score. Conditional multivariable logistic regression was used for primary analysis and nonparametric tests for comparison between groups. In a cohort of 1284 adult patients, 45 cases and 180 controls were identified. Diastolic dysfunction (DD) was an independent predictor (OR 5.26, 95% CI 1.03‐28.57, P = .04) of systolic HF in multivariable analysis. Stress‐induced cardiomyopathy was the most common etiology. Left ventricular function recovered in 21 patients. Pretransplant DD decreased the chances of recovery (P = .05). In conclusion, patients with pretransplant DD need close post‐transplant follow‐up for timely identification of HF.
The role of Nrf2 signaling in counteracting neurodegenerative diseases
Authors: Dinkova‐Kostova Albena T. , Kostov Rumen V. , Kazantsev Aleksey G.
Published: January 2018

The transcription factor Nrf2 (nuclear factor‐erythroid 2 p45‐related factor 2) functions at the interface of cellular redox and intermediary metabolism. Nrf2 target genes encode antioxidant enzymes, and proteins involved in xenobiotic detoxification, repair and removal of damaged proteins and organelles, inflammation, and mitochondrial bioenergetics. The function of Nrf2 is altered in many neurodegenerative disorders, such as Huntington's disease, Alzheimer's disease, amyotrophic lateral sclerosis, and Friedreich's ataxia. Nrf2 activation mitigates multiple pathogenic processes involved in these neurodegenerative disorders through upregulation of antioxidant defenses, inhibition of inflammation, improvement of mitochondrial function, and maintenance of protein homeostasis. Small molecule pharmacological activators of Nrf2 have shown protective effects in numerous animal models of neurodegenerative diseases, and in cultures of human cells expressing mutant proteins. Targeting Nrf2 signaling may provide a therapeutic option to delay onset, slow progression, and ameliorate symptoms of neurodegenerative disorders.
Soil phosphorus does not keep pace with soil carbon and nitrogen accumulation following woody encroachment
Authors: Zhou Yong , Boutton Thomas W. , Wu X. Ben
Published: January 2018

Soil carbon, nitrogen, and phosphorus cycles are strongly interlinked and controlled through biological processes, and the phosphorus cycle is further controlled through geochemical processes. In dryland ecosystems, woody encroachment often modifies soil carbon, nitrogen, and phosphorus stores, although it remains unknown if these three elements change proportionally in response to this vegetation change. We evaluated proportional changes and spatial patterns of soil organic carbon (SOC), total nitrogen (TN), and total phosphorus (TP) concentrations following woody encroachment by taking spatially explicit soil cores to a depth of 1.2 m across a subtropical savanna landscape which has undergone encroachment byProsopis glandulosa(an N2fixer) and other woody species during the past century in southern Texas,USA.SOCandTNwere coupled with respect to increasing magnitudes and spatial patterns throughout the soil profile following woody encroachment, whileTPincreased slower thanSOCandTNin topmost surface soils (0–5 cm) but faster in subsurface soils (15–120 cm). Spatial patterns ofTPstrongly resembled those of vegetation cover throughout the soil profile, but differed from those ofSOCandTN, especially in subsurface soils. The encroachment of woody species dominated by N2‐fixing trees into this P‐limited ecosystem resulted in the accumulation of proportionally less soil P compared to C and N in surface soils; however, proportionally more P accrued in deeper portions of the soil profile beneath woody patches where alkaline soilpHand high carbonate concentrations would favor precipitation of P as relatively insoluble calcium phosphates. This imbalanced relationship highlights that the relative importance of biotic vs. abiotic mechanisms controlling C and N vs. P accumulation following vegetation change may vary with depth. Our findings suggest that efforts to incorporate effects of land cover changes into coupled climate–biogeochemical models should attempt to represent C‐N‐P imbalances that may arise following vegetation change.
Peer teaching and information retrieval: the role of the NICE Evidence search student champion scheme in enhancing students’ confidence
Authors: Sbaffi Laura , Hallsworth Elaine , Weist Anne
Published: January 2018

Background

This research reports on the NICE Evidence search (ES) student champion scheme (SCS) first five years of activity (2011–2016) in terms of its impact on health care undergraduate students’ information search skills and search confidence.

Objectives

A review of students’ evaluation of the scheme was carried out to chart the changes in attitude towards NICE Evidence search as an online health care information source and to monitor students’ approach to information seeking.

Methods

This study is based on the results of questionnaires distributed to students before and after attending a training session on NICE Evidence search delivered by their own peers. The exercise was implemented in health related universities in England over a period of five consecutive academic years.

Results

(i) Students’ search confidence improved considerably after the training; (ii) ES was perceived as being an increasingly useful resource of evidence based information for their studies; (iii) the training helped students develop discerning search skills and use evidence based information sources more consistently and critically.

Conclusions

The NICE SCS improves confidence in approaching information tasks amongst health care undergraduate students. Future developments could involve offering the training at the onset of a course of study and adopting online delivery formats to expand its geographical reach.
Three‐dimensional reconstruction of prostate cancer architecture with serial immunohistochemical sections: hallmarks of tumour growth, tumour compartmentalisation, and implications for grading and heterogeneity
Authors: Tolkach Yuri , Thomann Stefan , Kristiansen Glen
Published: January 2018

Aims

Conventional morphology of prostate cancer considers only the two‐dimensional (2D) architecture of the tumour. Our aim was to examine the feasibility of three‐dimensional (3D) reconstruction of tumour morphology based on multiple consecutive histological sections and to decipher relevant features of prostate cancer architecture.

Methods and results

Seventy‐five consecutive histological sections (5 μm) of a typical prostate adenocarcinoma (Gleason score of 3 + 4 = 7) were immunostained (pan‐cytokeratin) and scanned for further 3D reconstructions with fiji/imagej software. The main findings related to the prostate cancer architecture in this case were: (i) continuity of all glands, with the tumour being an integrated system, even in Gleason pattern 4 with poorly formed glands—no short‐range migration of cells by Gleason pattern 4 (poorly formed glands); (ii) no repeated interconnections between the glands, with a tumour building a tree‐like branched structure with very ‘plastic’ branches (maximal depth of investigation 375 μm); (iii) very stark compartmentalisation of the tumour related to extensive branching, the coexistence of independent terminal units of such branches in one 2D slice explaining intratumoral heterogeneity; (iv) evidence of a craniocaudal growth direction in interglandular regions of the prostate and for a lateromedial growth direction in subcapsular posterolateral regions; and (v) a 3D architecture‐based description of Gleason pattern 4 with poorly formed glands, and its continuum with Gleason pattern 3.

Conclusions

Consecutive histological sections provide high‐quality material for 3D reconstructions of the tumour architecture, with excellent resolution. The reconstruction of multiple regions in this typical case of a Gleason score 3 + 4 = 7 tumour provides insights into relevant aspects of tumour growth, the continuity of Gleason patterns 3 and 4, and tumour heterogeneity.
Duration of androgen deprivation therapy and nadir of testosterone at 20 ng/dL predict testosterone recovery to supracastrate level in prostate cancer patients who received external beam radiotherapy
Authors: Takei Akinori , Sakamoto Shinichi , Wakai Ken , Tamura Takaaki , Imamura Yusuke , Xu Minhui , Maimaiti Maihulan , Kawamura Koji , Imamoto Takashi , Komiya Akira , Akakura Koichiro , Ichikawa Tomohiko
Published: January 2018

Objectives

To determine the predictors of testosterone recovery after termination of androgen deprivation therapy in high/intermediate‐risk prostate cancer patients receiving external beam radiation therapy with neoadjuvant and adjuvant androgen deprivation therapy.

Methods

A total of 82 patients who underwent external beam radiation therapy with androgen deprivation therapy for prostate cancer were retrospectively analyzed. Serum testosterone levels after androgen deprivation therapy terminations were studied. Cox proportional hazard models and the Kaplan–Meier method were used for statistical analysis.

Results

Median age, baseline testosterone, nadir testosterone and duration of androgen deprivation therapy were 73 years, 456 ng/dL, 16 ng/dL and 26 months, respectively. Androgen deprivation therapy duration of 33 months (hazard ratio 0.13; P = 0.0018), nadir testosterone of 20 ng/dL (hazard ratio 0.35; P = 0.0112) and testosterone >50 ng/dL at 6 months after androgen deprivation therapy termination (hazard ratio 0.21; P = 0.0075) were significantly associated with testosterone recovery to normal levels (200 ng/dL) on multivariate analysis. Androgen deprivation therapy duration of 33 months (hazard ratio 0.31; P = 0.0023) and nadir testosterone of 20 ng/dL (hazard ratio 0.38; P = 0.0012) were significantly associated with testosterone recovery to the supracastrate level (50 ng/dL) on multivariate analysis. After dividing patients into three risk groups, the rate of testosterone recovery to the normal level after 2 years of androgen deprivation therapy termination was 100% in the low‐risk group versus 20.8% in the high‐risk group (P < 0.0001); the rate of testosterone recovery to the supracastrate level was 100% in the low‐risk group versus 51.5% in the high‐risk group (P < 0.0001).

Conclusions

Duration of androgen deprivation therapy and achievement of nadir testosterone 20 ng/dL both predict testosterone recovery to the supracastrate level in prostate cancer patients undergoing external beam radiation therapy with androgen deprivation therapy.
Boron‐dependent microstructural evolution, thermal stability, and crystallization of mechanical alloying derived SiBCN
Authors: Li Daxin , Yang Zhihua , Jia Dechang , Cai Delong , Wang Shengjin , Chen Qingqing , Zhou Yu , Yu Dongli , Tian Yongjun
Published: January 2018

Amorphous boron‐rich SiBCN were prepared by high‐energy ball‐milling of the mixtures of Si, graphite, h‐BN, and inorganic boron, which acted as extra boron source. The solid‐state amorphization, thermal stability, and crystallization of the boron‐rich SiBCN were studied in detail. It was suggested that mechanical alloying can drive solid‐state amorphization but also can be an initiation step for the nucleation of nanocrystals. The amorphous networks of Si‐C, C‐B, C‐C, C‐N, B‐N, and C‐B‐N bonds are detected by XPS; however, solid‐state NMR further confirms the formation of a new chemical environment around B atoms, BC3. The increases in boron content improve the thermal stability of SiBCN ceramics but weaken their oxidation resistance. Nano‐SiC crystallizes first while BN(C) forms subsequently. Boron promoting SiC crystallization may result from the reduced hindering effects of B‐N‐C nanodomains that retard SiC crystallization.
On the persistence and dynamics of Big 4 real audit fees: Evidence from the UK
Authors: Kacer Marek , Peel David A. , Peel Michael J. , Wilson Nicholas
Published: January 2018

Despite the huge audit pricing literature, there is a dearth of evidence on the temporal dynamics of audit fee adjustments and the persistence of audit fees. Based on a sample of 76,867 panel observations for a sample of UK companies audited by the Big 4 over the period 1998 to 2012, we employ consistent lagged dependent variable panel estimators to provide new evidence on the persistence and dynamics of real Big 4 audit fees. Contrary to extant research, which assumes that audit fees adjust immediately in a single period, our empirical results indicate that Big 4 real audit fees are persistent, being partly dependent on their previous realisations. We conclude that static audit fee models omit a potentially important temporal dimension of audit pricing behaviour and that further research is warranted into dynamic audit fee models across other jurisdictions.
Difficulties with Fine Motor Skills and Cognitive Impairment in an Elderly Population: The Progetto Veneto Anziani
Authors: Curreri Chiara , Trevisan Caterina , Carrer Pamela , Facchini Silvia , Giantin Valter , Maggi Stefania , Noale Marianna , De Rui Marina , Perissinotto Egle , Zambon Sabina , Crepaldi Gaetano , Manzato Enzo , Sergi Giuseppe
Published: January 2018

Objectives

To investigate dysfunction in fine motor skills in a cohort of older Italian adults, identifying their prevalence and usefulness as indicators and predictors of cognitive impairment.

Design

Population‐based longitudinal study with mean follow‐up of 4.4 years.

Setting

Community.

Participants

Older men and women enrolled in the Progetto Veneto Anziani (Pro.V.A.) (N = 2,361); 1,243 subjects who were cognitively intact at baseline were selected for longitudinal analyses.

Measurements

Fine motor skills were assessed by measuring the time needed to successfully complete two functional tasks: putting on a shirt and a manual dexterity task. Cognitive impairment was defined as a Mini‐Mental State Examination (MMSE) score less than 24.

Results

On simple correlation, baseline MMSE score was significantly associated with the manual dexterity task (correlation coefficient (r) = −0.25, P < .001) and time needed to put on a shirt (r = −0.29, P < .001). Over the study period, changes in time needed to perform the fine motor tasks were significantly associated with changes in MMSE (putting on a shirt: β = 0.083, P = .003; manual dexterity task: β = 0.098, P < .001). Logistic regression analyses confirmed that worse results on tasks were associated with cognitive impairment at baseline (odds ratio (OR) = 2.47, 95% confidence interval (CI) = 1.74–3.50, for the fourth quartile of time needed to put on a shirt; OR = 1.98, 95% CI = 1.42–2.76, for the fourth manual dexterity task quartile) and greater risk of cognitive impairment developing during follow‐up (OR = 4.38, 95% CI = 2.46–7.80, for the fourth quartile of time needed to put on a shirt; OR = 2.20, 95% CI = 1.30–3.72, for the fourth manual dexterity task quartile).

Conclusions

Difficulties with fine motor skills are common in older adults, and assessing them may help to identify early signs of dementia, subjects at high risk to develop cognitive decline, and individuals who can be referred to specialists.
Non‐surgical periodontal therapy reduces salivary adipocytokines in chronic periodontitis patients with and without obesity
Authors: Al‐Hamoudi Nawwaf , Abduljabbar Tariq , Mirza Sana , Al‐Sowygh Zeyad H. , Vohra Fahim , Javed Fawad , Akram Zohaib
Published: January 2018

Aim

The aim of the present study was to assess the effect of scaling and root planing (SRP) on periodontal parameters and whole salivary resistin and interleukin (IL)‐6 levels in chronic periodontitis (CP) patients with and without obesity.

Methods

Participants were divided into two groups; group 1 included obese and non‐obese individuals with CP; and group 2 included obese and non‐obese individuals without CP. In both groups, bleeding on probing (BOP) and probing depth (PD) ≥4 mm and whole salivary resistin and IL‐6 levels were measured using enzyme‐linked immunosorbent assay at baseline and 6 months after SRP. The number of missing teeth was counted, and marginal bone loss was measured on digital panoramic radiographs at baseline and 6 months' postoperatively.

Results

BOP was significantly higher among obese patients in group 1 than obese (P < .001) and non‐obese (P < .001) individuals in group 2. At 6 months' follow up, BOP (P < .001) and PD ≥4 mm (P < .001) were significantly lower among obese and non‐obese patients in group 1 than their respective baseline values. At 6 months' follow up, BOP (P < .001) and PD ≥4 mm (P < .001) were significantly higher among obese and non‐obese individuals in group 1 compared with individuals in group 2.

Conclusion

SRP is effective in reducing periodontal inflammation in CP patients with and without obesity. CP seems to be the primary factor that influences periodontal status and the expression of resistin and IL‐6 levels in obese and non‐obese patients.
Analogous on‐axis interference topographic phase microscopy (AOITPM)
Authors: XIU P. , LIU Q. , ZHOU X. , XU Y. , KUANG C. , LIU X.
Published: January 2018

The refractive index (RI) of a sample as an endogenous contrast agent plays an important role in transparent live cell imaging. In tomographic phase microscopy (TPM), 3D quantitative RI maps can be reconstructed based on the measured projections of the RI in multiple directions. The resolution of the RI maps not only depends on the numerical aperture of the employed objective lens, but also is determined by the accuracy of the quantitative phase of the sample measured at multiple scanning illumination angles. This paper reports an analogous on‐axis interference TPM, where the interference angle between the sample and reference beams is kept constant for projections in multiple directions to improve the accuracy of the phase maps and the resolution of RI tomograms. The system has been validated with both silica beads and red blood cells. Compared with conventional TPM, the proposed system acquires quantitative RI maps with higher resolution (420 nm @λ = 633 nm) and signal‐to‐noise ratio that can be beneficial for live cell imaging in biomedical applications.
Remineralization of Natural Human Carious Dentin Lesions with an Experimental Whisker‐Reinforced Atraumatic Restorative Treatment Composite
Authors: Zhang Chao , Campbell Stephen D. , Dickens Sabine H. , Yang Bin
Published: January 2018

Purpose

To evaluate the remineralization of natural human dentin caries with an experimental whisker‐reinforced Atraumatic Restorative Treatment (ART) composite.

Materials and Methods

Teeth with moderate active dentin caries were prepared with caries‐disclosing dye and hand instruments, restored with ART or resin‐modified glass ionomer cement (RM‐GIC), and then wet sliced into 120‐µm sections with 15 sections in each group. After taking transverse microradiographs and implementing digital image analysis to determine the “mineral‐loss‐before,” each section was incubated in artificial saliva solution (pH = 7.0) for 4 weeks and 8 weeks with 1 hour each workday in demineralization solution (pH = 4.3). Transverse microradiographs of each section were retaken, and the “mineral‐loss‐after” was determined. The remineralization was calculated from [1‐(“mineral‐loss‐after”/“mineral‐loss‐before”)] × 100%. Results were statistically analyzed with a repeated‐measures ANOVA with one within‐subject factor (time: 4 and 8 weeks) and one between‐subject factor (material: ART and RM‐GIC) (α = 0.05).

Results

The statistical analysis indicated that ART composite resulted in significantly higher remineralization than the RM‐GIC (p ≤ 0.05). For the remineralization of each material, there was a statistical difference between 4 weeks and 8 weeks (p ≤ 0.05).

Conclusions

This experimental ART composite remineralized natural human dentin caries better than the RM‐GIC.
Type and timing of dietary acid intake and tooth wear among American adults
Authors: Al‐Zwaylif Lynn H. , O'Toole Saoirse , Bernabé Eduardo
Published: January 2018

Objectives

To explore the interrelationship between type and timing of dietary acid intake and tooth wear among American adults.

Methods

This study used data from 3,586 adults, aged 18 years and older, who participated in the National Health and Nutrition Examination Survey (NHANES) 2003‐04. Information on four types of acidic food and beverages (fruits, fruit juices, alcoholic drinks, and soft drinks) and timing of consumption (meals versus snacks, defined according to percentage of total energy intake, self‐reported eating occasion, and time of day) was extracted from two 24‐hour dietary recalls. The association of the type and timing of dietary acid intake with the number of surfaces with moderate‐to‐severe tooth wear was assessed in Hurdle models to account for the excess zero counts and over‐dispersion. Models were adjusted for socio‐demographic factors, acid reflux medication, and dental insurance coverage.

Results

The daily intake of soft drinks was associated with tooth wear, while those of fruits, fruit juices, and alcoholic drinks were not. The consumption of soft drinks with meals was the only factor consistently associated with tooth wear, irrespective of the method used to define meals versus snacks. The above associations were found with the number of surfaces with tooth wear (among those with the condition), but not with the odds of having tooth wear (among all participants).

Conclusion

The consumption of soft drinks with meals was associated with moderate‐to‐severe tooth wear among American adults. Other acidic foods and beverages were not associated with tooth wear, regardless of their timing of consumption.
Proteinuria in neuronal intranuclear inclusion disease
Authors: Fukai Yuta , Yorimitsu Daisuke , Nishimura Hirotake , Kutoku Yumiko , Sasaki Tamaki , Kashihara Naoki , Ohsawa Yutaka , Sunada Yoshihide
Published: January 2018

Recently, clinical features of adult‐onset neuronal intranuclear inclusion disease have gradually become characterized by premortem diagnoses based on eosinophilic, ubiquitin‐positive intranuclear inclusions demonstrated using skin biopsy specimens. A 65‐year‐old healthy woman with proteinuria was admitted because of cognitive impairment and walking instability. She had frontal lobe dysfunction and sensory ataxia with high‐signal‐intensity lesions in the corticomedullary junction on performing diffusion‐weighted brain magnetic resonance imaging. She was incidentally diagnosed with adult‐onset sporadic neuronal intranuclear inclusion disease based on the presence of intranuclear inclusions in renal biopsy specimens. Proteinuria might be a non‐neuronal symptom of neuronal intranuclear inclusion disease because no other causes for proteinuria were found on renal testing.
The Individual‐Level Effect of Gender Matching in Representative Bureaucracy
Authors: Guul Thorbjørn Sejr
Published: January 2018

A substantial literature links passive bureaucratic gender representation to better outcomes for represented citizens. However, because existing studies have been carried out primarily at the organizational level, it is not known whether these effects are caused by individual‐level interaction or by organizational processes. This article investigates whether gender matching in individual relationships affects citizen outcomes. The context of the study is a program in which young job seekers without vocational training were assigned to a job counselor for one‐on‐one meetings. The article finds that gender matching has a positive effect on citizen outcomes and that this effect is partly explained by an increased level of effort on the part of the citizen. This implies that citizen outcomes can be improved by matching bureaucrats and citizens of the same gender or by providing training to bureaucrats to enable them to better serve citizens of the opposite gender.
Exploration of experimental design and statistical methods using the stick‐on‐the‐wall spaghetti rule
Authors: Montangero Simone , Vittone Francesca , Olderbak Sally , Wilhelm Oliver
Published: January 2018

We present a versatile scenario to introduce students to statistics: the test that spaghetti sticks only if sufficiently done. The statistical analyses can be performed at different levels of complexity and formal correctness, adapting it to the students' age.
Current practices in perioperative blood management for patients undergoing liver resection: a survey of surgeons and anesthesiologists
Authors: Bennett Sean , Ayoub Abdul , Tran Alexandre , English Shane , Tinmouth Alan , McIsaac Daniel I. , Fergusson Dean , Martel Guillaume
Published: January 2018

BACKGROUND

Development of intraoperative techniques and blood management strategies in liver resection, and the multidisciplinary nature of perioperative transfusion decision making, creates an opportunity for practice variation. The aim of this study was to describe the current practices in perioperative blood management and explore differences between surgeons and anesthesiologists.

STUDY DESIGN AND METHODS

A Web‐based survey was developed, piloted, and circulated to Canadian liver surgeons and anesthesiologists. The survey focused on management of preoperative anemia, blood conservation strategies, estimation of blood loss, and transfusion decision making in a multidisciplinary setting.

RESULTS

A total of 198 physicians received the survey, with 117 responding (59%). Most responding surgeons (67%) perform more than 20 liver resections per year, while most responding anesthesiologists (90%) take part in fewer than 20. Anesthesiologists most commonly stated that preoperative anemia is managed by someone else (38%), while surgeons most commonly reported “no specific treatment” (45%). The most common intraoperative blood conservation technique used is administration of antifibrinolytics (63% used them at least occasionally). The most important factor for anesthesiologists when deciding on an intraoperative transfusion was hemoglobin value (47%); for surgeons, it was patient hemodynamics (33%). Compared to when they started their career, 60% of respondents felt that they were less likely to transfuse a patient now.

CONCLUSION

The results of our survey provide insights into current transfusion practice and decision making in liver resection, including a comparison between anesthesiologist and surgeon transfusion behavior. Management of preoperative anemia, increased use of intraoperative blood conservation techniques, and improved communication between providers were identified as targets for quality improvement.
Enteral nutrition for the intubated adult intensive care unit patient prior to general anesthesia: a scoping review protocol
Authors: Barrick Christy , Stewart Mary W.
Published: January 2018

Review question:

The objectives of this scoping review are to examine and map fasting times for adult intubated intensive care unit (ICU) patients prior to general anesthesia and patient outcomes following the cessation of enteral nutrition, to examine and conceptually map the evidence, and identify any gaps.

Specifically, the review questions are:

What fasting times are implemented prior to general anesthesia among adult intubated ICU patients?

Do fasting times vary, depending on the type of surgical intervention?

What outcomes, including but not limited to aspiration, malnutrition and mortality, have been reported following the cessation of enteral nutrition prior to general anesthesia among adult intubated ICU patients?
Vocational rehabilitation for emergency services personnel: a scoping review protocol
Authors: Alexander Lyndsay , Cooper Kay
Published: January 2018

Review question:

The objective of this scoping review is to examine and map the range of vocational rehabilitation available for law enforcement and emergency services personnel.

More specifically, the scoping review questions are:

1. What types of vocational rehabilitation for police fire, and emergency medical service personnel from developed countries have been reported?

2. What are the characteristics of the vocational rehabilitation (such as but not limited to physical interventions, psychological interventions or mixed content interventions) reported for police, fire and emergency medical service personnel from developed countries?

3. In what context (healthcare setting, work setting or rehabilitation setting) are the vocational rehabilitation programs provided for police, fire and emergency medical service personnel from developed countries?
Programmable Multistable Mechanisms: Synthesis and Modeling
Authors: Zanaty Mohamed , Vardi Ilan , Henein Simon
Published: January 2018

Compliant mechanisms can be classified according to the number of their stable states and are called multistable mechanisms if they have more than one stable state. We introduce a new family of mechanisms for which the number of stable states is modified by programming inputs. We call such mechanisms programmable multistable mechanisms (PMM). A complete qualitative analysis of a PMM, the T-mechanism, is provided including a description of its multistability as a function of the programming inputs. We give an exhaustive set of diagrams illustrating equilibrium states and their stiffness as one programming input varies while the other is fixed. Constant force behavior is also characterized. Our results use polynomial expressions for the reaction force derived from Euler–Bernoulli beam theory. Qualitative behavior follows from the evaluation of the zeros of the polynomial and its discriminant. These analytical results are validated by numerical finite element method simulations.
Thermodynamic Analysis of Power Generation Cycles With High-Temperature Gas-Cooled Nuclear Reactor and Additional Coolant Heating Up to 1600 °C
Authors: Dudek Michał , Kolenda Zygmunt , Jaszczur Marek , Stanek Wojciech
Published: January 2018

Nuclear energy is one of the possibilities ensuring energy security, environmental protection, and high energy efficiency. Among many newest solutions, special attention is paid to the medium size high-temperature gas-cooled reactors (HTGR) with wide possible applications in electric energy production and district heating systems. Actual progress can be observed in the literature and especially in new projects. The maximum outlet temperature of helium as the reactor cooling gas is about 1000 °C which results in the relatively low energy efficiency of the cycle not greater than 40–45% in comparison to 55–60% of modern conventional power plants fueled by natural gas or coal. A significant increase of energy efficiency of HTGR cycles can be achieved with the increase of helium temperature from the nuclear reactor using additional coolant heating even up to 1600 °C in heat exchanger/gas burner located before gas turbine. In this paper, new solution with additional coolant heating is presented. Thermodynamic analysis of the proposed solution with a comparison to the classical HTGR cycle will be presented showing a significant increase of energy efficiency up to about 66%.
Flow-Induced Vibration and Hydrokinetic Power Conversion of Two Staggered Rough Cylinders for 2.5 × 104 < Re < 1.2 × 105
Authors: Xu Wanhai , Ji Chunning , Sun Hai , Ding Wenjun , Bernitsas Michael M.
Published: January 2018

Flow-induced vibration (FIV), primarily vortex-induced vibrations (VIV), and galloping have been used effectively to convert hydrokinetic energy to electricity in model-tests and field-tests by the Marine Renewable Energy Laboratory (MRELab) of the University of Michigan. It is known that the response of cylinders with passive turbulence control (PTC) undergoing vortex shedding differs from the oscillation of smooth cylinders in a similar configuration. Additional investigation on the FIV of two elastically mounted circular cylinders in a staggered arrangement with low mass ratio in the TrSL3 flow-regime is required and is contributed by this paper. The two PTC-cylinders were allowed to oscillate in the transverse direction to the oncoming fluid flow in a recirculating water channel. The cylinder model with a length of 0.895 m and a diameter of 8.89 cm, a mass ratio of 1.343 was used in the tests. The Reynolds number was in the range of 2.5 × 104 < Re < 1.2 × 105, which is a subset of the TrSL3 flow-regime. The center-to-center longitudinal and transverse spacing distances were T/D = 2.57 and S/D = 1.0, respectively. The spring stiffness values were in the range of 400 < K (N/m) <1200. The values of harnessing damping ratio tested were ζharness = 0.04, 0.12 and 0.24. For the values tested, the experimental results indicate that the response of the upstream cylinder is similar to the single cylinder. The downstream cylinder exhibits more complicated vibrations. In addition, the oscillation system of two cylinders with stiffer spring and higher ζharness could initiate total power harness at a higher flow velocity and obtain more power.
Influence of MoS2, H3BO3, and MWCNT Additives on the Dry and Lubricated Sliding Tribology of AMMC–Steel Contacts
Authors: Singh Harpreet , Singh ParamPreet , Bhowmick Hiralal
Published: January 2018

The present study is focused on the performance evaluation of MoS2, H3BO3, and multiwall carbon nanotubes (MWCNT) used as the potential oil additives in base oil for aluminum metal matrix composites (AMMC)–steel (EN31) tribocontact. Al–B4C composite is used for this purpose; based on a set of preliminary investigation under unlubricated and fresh oil lubrication, three different types of AMMCs (Al–SiC, Al–B4C, and Al–SiC–B4C) were used. A pin-on-disk tribometer is used for all the friction and wear tests under operating condition of load 9.8 N and sliding velocity of 0.5 m/s. From the particle-based wet tribology, it is clear that both the additives H3BO3 and MWCNT improve the friction as well as wear behavior for selected composite contacts. Multiwall carbon nanotubes emerged out as superior among all the additives, whereas MoS2 additives show marginal enhancement in frictional performance under given operating conditions. Fractography and morphological study of pin specimens are carried out to identify the underlying friction and wear mechanisms.
Baseline Evaluation of Ignition Timing and Compression Ratio Configurations on Efficiency and Combustion Stability of a Small-Bore, Two-Stroke, Natural Gas Engine
Authors: Darzi Mahdi , Johnson Derek , Ulishney Chris , Bade Mehar , Zamani Nima
Published: January 2018

Two-stroke engines continue to dominate the small engine market based on cost and simplicity, though companies have incorporated small four-stroke engines into handheld equipment. On the other end of the displacement spectrum, two-stroke natural gas engines are common in large-bore applications within the natural gas compression industry. Nearly 60% of homes utilize natural gas and could therefore benefit from its use as fuel for decentralized power generation. Such use for home applications does not require significant investment in infrastructure, which has limited its penetration into the transportation sector. Companies already offer back-up power generation systems for home use fueled by either natural gas or propane. These systems are often cost prohibitive and rely on four-stroke engines.

The ultimate goal is to apply advanced technologies, such as direct fuel injection, to improve efficiency of small two-stroke engines. To establish a baseline, researchers developed a micro-engine test facility to examine effects of ignition timing, compression ratio, and intake and exhaust systems on efficiency and combustion stability. This research focuses on an air-cooled, spark-ignited, two-stroke engine converted to operate on natural gas. In addition to fuel conversion, an electronic ignition system replaced the stock magneto driven coil. The added trigger wheel provided a signal for control of ignition and injection timing, and for in-cylinder pressure time alignment. Engine displacement was 29-cc with a bore and stroke of 35 mm and 30 mm. Tests were performed on gasoline and a natural gas blend at an engine speed of 5400 RPM. Fuel flow was adjusted for each case to produce maximum brake torque. Two different fuel delivery methods were tested for natural gas — a mass flow controller and an electronic port fuel injector. Tests examined the effects of two compression ratios for spark timings of 15, 20, 25, and 30 CAD BTDC. Fumigation and port injection decreased efficiency compared to gasoline by 24 and 32%, respectively. Brake power also decreased by 64 and 65% on average. A similar trend occurred for delivery ratio due to the volume of fresh air displaced by natural gas. Delivery ratio of fumigation and port injection decreased compared to gasoline by 12 and 27%, respectively. The coefficient of variation in indicated mean effective pressure varied from six to 27% over compression ratio and ignition timing sweeps.
Flutter Suppression of Bridge Deck Section With Controllable Winglets Using Output Feedback
Authors: Bera K. K. , Chandiramani N. K.
Published: January 2018

Control of wind induced flutter of a bridge deck is studied using static output feedback. Servomotor actuated winglets provide the control forces. Deck and winglets are modeled as flat plates and their aerodynamic interaction is neglected. Self excited wind forces acting on deck and winglets are modeled using the Scanlan-Tomko model, with flat plate flutter derivatives obtained from Theodorsen functions. Rogers rational function approximation is used for time domain representation of wind forces in order to simplify the stability and control analyses. Control input to servomotors is based on direct feedback of vertical and torsional displacements of deck. Feedback gains that are constant, or varying with wind speed, are considered. Winglet rotations being restricted, flutter and divergence behavior is studied using system eigenvalues as well as responses. Results show that variable gain output feedback control provides the maximum increase in critical speed and also response attenuation, followed by control with gain scheduling. Control with constant gain is least effective.
A Study of Roll Induced by Crane Motion on Ships: A Case Study of the Use of the Moving Frame Method
Authors: Nordvik Andreas , Khan Natalia , Burcă Roberto Andrei , Impelluso Thomas J.
Published: January 2018

This paper presents a new method in dynamics — The Moving Frame Method (MFM) — and applies it to analyze the roll, yaw and pitch of a ship at sea, as induced by an onboard moving crane. The MFM, founded on Lie Group Theory, Cartan’s Moving Frames and a compact notation from geometrical physics, enables this expedited extraction of the equations of motion. Next, the method deploys the power of the special Euclidean Group SE(3) and a restricted variation to be used in Hamilton’s Principle, to extract the equations of motion. The mathematical model is then simplified to get a clearer picture of the parameters that impact the motion of the crane. The equations of interest are numerically solved by using fourth order Runge-Kutta method to obtain the specific data for the motion induced by the crane. Then, The Cayley-Hamilton theorem is used to reconstruct the rotation matrix. To supplement the paper, a webpage is coded with a model of the crane and ship, to graphically visualize the motion in 3D. It is imperative to note that while there are many approaches to dynamics, the MFM presents a consistent method, from 2D to 3D, and across sub-disciplines. The simplification is what has enabled undergraduate students to undertake this project.
Machinability Study on SiC Particle Reinforced Aluminum Alloy Composite (SiCp/Al) Material With CVD Diamond Coated End Mills
Authors: Vargas Alexandro , Nguyen Tony , Liu Jiancheng
Published: January 2018

Particle-reinforced metal matrix composites (pMMC) such as silicon carbide particle reinforced aluminum alloys (SiCp/Al) require special cutting tools due to the high hardness and abrasive properties of the ceramic particles. Diamond coated cutting tools are ideal for machining this type of pMMC. Previous research studies focus on the machinability of pMMCs with low ceramic content. The aim of this research is to determine the optimal cutting parameters for machining SiCp/Al material containing high silicon carbide particle reinforcement (>25%). Material removal rate (MRR) was used to determine the optimal cutting parameters with the tool wear and surface roughness as constraints. Cutting speed, feed rate, and depth of cut were used as design parameters for the design of experiment. High burr formation and cutting forces were observed during the experiments. Experimental milling tests are conducted using CVD diamond coated end mills and non-diamond tungsten carbide end mills. It was found that low tool rotation speeds, feed rates and depths of cut are necessary to achieve smoother surface finishes of Ra < 1 μm. A high MRR to low tool wear and surface roughness ratio was obtainable at a tool rotation speed of 6500 r/min, feed rate of 762 mm/min, and depth of cut of 3 mm. Results showed that a smooth surface roughness of the workpiece material was achieved with non-diamond tungsten carbide end mills, however, this was at the expense of extreme tool wear and high burr formation. An endurance test was run to test for complete tool failure.
Three-Dimensional CFD Simulation of Prime Mover Stirling Engine
Authors: Rogdakis E. , Bitsikas P. , Dogkas G.
Published: January 2018

A three-dimensional Computational Fluid Dynamics - CFD simulation is conducted on a Stirling engine. The temperature in the engine spaces and the temperature profile along the regenerator are graphically presented, along with the density and the gas flow patterns in selected parts of the engine. The maximum value of pressure drop is slightly more than 6% of the mean engine pressure at the same instance. The maximum loss due to pressure drop is equal to 5 kW.

In addition, the CFD results are compared to those coming from a one-dimensional model. The comparison includes data regarding the pressure of the gas during the engine cycle, the gas mass flow-rate in all the engine spaces, the respective points of flow reversal and the gas pressure drop.

Finally, the net work output and efficiency of the engine are calculated. The net work output of the engine is equal to 6.7 kW and the engine’s efficiency is equal to 51%. The possible sources of further losses are discussed.
A Flexible-Matrix-Composite Hydraulic Engine Mount
Authors: Chokshi K. , Ghoneim H.
Published: January 2018

An effective hydraulic engine mount (HEM) should acquire a high dynamic stiffness (storage and loss) at low frequency, and low dynamic stiffness at high frequency. A passive hydraulic engine mount which can achieve this hard/soft dynamic stiffness requirement is proposed. Three new approaches are adopted in the proposed HEM: elimination of the decoupler, application of a hyperbolic flexible-matrix-composite pumping chamber, and employment of two oppositely connected identical HEM. The working principle of the proposed HEM is explained, the mathematical model is introduced, and the effect of the various physical parameters of the physical model on the dynamic stiffness are presented. It is shown that the proposed HEM can achieve the hard/soft requirement over a specific frequency range.