bluuebunny/crossref_metadata_2025 huggingface dataset:
iEnhancer-ECNN: identifying enhancers and their strength using ensembles of convolutional neural networks
Authors: Nguyen Quang H. , Nguyen-Vo Thanh-Hoang , Le Nguyen Quoc Khanh , Do Trang T.T. , Rahardja Susanto , Nguyen Binh P.
Published: December 2019

Background

Enhancers are non-coding DNA fragments which are crucial in gene regulation (e.g. transcription and translation). Having high locational variation and free scattering in 98% of non-encoding genomes, enhancer identification is, therefore, more complicated than other genetic factors. To address this biological issue, several in silico studies have been done to identify and classify enhancer sequences among a myriad of DNA sequences using computational advances. Although recent studies have come up with improved performance, shortfalls in these learning models still remain. To overcome limitations of existing learning models, we introduce iEnhancer-ECNN, an efficient prediction framework using one-hot encoding and k-mers for data transformation and ensembles of convolutional neural networks for model construction, to identify enhancers and classify their strength. The benchmark dataset from Liu et al.’s study was used to develop and evaluate the ensemble models. A comparative analysis between iEnhancer-ECNN and existing state-of-the-art methods was done to fairly assess the model performance.

Results

Our experimental results demonstrates that iEnhancer-ECNN has better performance compared to other state-of-the-art methods using the same dataset. The accuracy of the ensemble model for enhancer identification (layer 1) and enhancer classification (layer 2) are 0.769 and 0.678, respectively. Compared to other related studies, improvements in the Area Under the Receiver Operating Characteristic Curve (AUC), sensitivity, and Matthews’s correlation coefficient (MCC) of our models are remarkable, especially for the model of layer 2 with about 11.0%, 46.5%, and 65.0%, respectively.

Conclusions

iEnhancer-ECNN outperforms other previously proposed methods with significant improvement in most of the evaluation metrics. Strong growths in the MCC of both layers are highly meaningful in assuring the stability of our models.
JCDB: a comprehensive knowledge base for Jatropha curcas, an emerging model for woody energy plants
Authors: Zhang Xuan , Pan Bang-Zhen , Chen Maosheng , Chen Wen , Li Jing , Xu Zeng-Fu , Liu Changning
Published: December 2019

Background

Jatropha curcas is an oil-bearing plant, and has seeds with high oil content (~ 40%). Several advantages, such as easy genetic transformation and short generation duration, have led to the emergence of J. curcas as a model for woody energy plants. With the development of high-throughput sequencing, the genome of Jatropha curcas has been sequenced by different groups and a mass of transcriptome data was released. How to integrate and analyze these omics data is crucial for functional genomics research on J. curcas.

Results

By establishing pipelines for processing novel gene identification, gene function annotation, and gene network construction, we systematically integrated and analyzed a series of J. curcas transcriptome data. Based on these data, we constructed a J. curcas database (JCDB), which not only includes general gene information, gene functional annotation, gene interaction networks, and gene expression matrices but also provides tools for browsing, searching, and downloading data, as well as online BLAST, the JBrowse genome browser, ID conversion, heatmaps, and gene network analysis tools.

Conclusions

JCDB is the most comprehensive and well annotated knowledge base for J. curcas. We believe it will make a valuable contribution to the functional genomics study of J. curcas. The database is accessible at http://jcdb.liu-lab.com/.
Commensal microbiota modulates larval foraging behaviour, development rate and pupal production in Bactrocera tryoni
Authors: Morimoto Juliano , Nguyen Binh , Tabrizi Shabnam T. , Lundbäck Ida , Taylor Phillip W. , Ponton Fleur , Chapman Toni A.
Published: December 2019

Backround

Commensal microbes can promote survival and growth of developing insects, and have important fitness implications in adulthood. Insect larvae can acquire commensal microbes through two main routes: by vertical acquisition from maternal deposition of microbes on the eggshells and by horizontal acquisition from the environment where the larvae develop. To date, however, little is known about how microbes acquired through these different routes interact to shape insect development. In the present study, we investigated how vertically and horizontally acquired microbiota influence larval foraging behaviour, development time to pupation and pupal production in the Queensland fruit fly (‘Qfly’), Bactrocera tryoni.

Results

Both vertically and horizontally acquired microbiota were required to maximise pupal production in Qfly. Moreover, larvae exposed to both vertically and horizontally acquired microbiota pupated sooner than those exposed to no microbiota, or only to horizontally acquired microbiota. Larval foraging behaviour was also influenced by both vertically and horizontally acquired microbiota. Larvae from treatments exposed to neither vertically nor horizontally acquired microbiota spent more time overall on foraging patches than did larvae of other treatments, and most notably had greater preference for diets with extreme protein or sugar compositions.

Conclusion

The integrity of the microbiota early in life is important for larval foraging behaviour, development time to pupation, and pupal production in Qflies. These findings highlight the complexity of microbial relations in this species, and provide insights to the importance of exposure to microbial communities during laboratory- or mass-rearing of tephritid fruit flies.
Comparison of somatic variant detection algorithms using Ion Torrent targeted deep sequencing data
Authors: Wang Qing , Kotoula Vassiliki , Hsu Pei-Chen , Papadopoulou Kyriaki , Ho Joshua W. K. , Fountzilas George , Giannoulatou Eleni
Published: December 2019

Background

The application of next-generation sequencing in cancer has revealed the genomic landscape of many tumour types and is nowadays routinely used in research and clinical settings. Multiple algorithms have been developed to detect somatic variation from sequencing data using either paired tumour-blood or tumour-only samples. Most of these methods have been developed and evaluated for the identification of somatic variation using Illumina sequencing datasets of moderate coverage. However, a comprehensive evaluation of somatic variant detection algorithms on Ion Torrent targeted deep sequencing data has not been performed.

Methods

We have applied three somatic detection algorithms, Torrent Variant Caller, MuTect2 and VarScan2, on a large cohort of ovarian cancer patients comprising of 208 paired tumour-blood samples and 253 tumour-only samples sequenced deeply on Ion Torrent Proton platform across 330 amplicons. Subsequently, the concordance and performance of the three somatic variant callers were assessed.

Results

We have observed low concordance across the algorithms with only 0.5% of SNV and 0.02% of INDEL calls in common across all three methods. The intersection of all methods showed better performance when assessed using correlation with known mutational signatures, overlap with COSMIC variation and by examining the variant characteristics. The Torrent Variant Caller also performed well with the advantage of not eliminating a high number of variants that could lead to high type II error.

Conclusions

Our results suggest that caution should be taken when applying state-of-the-art somatic variant algorithms to Ion Torrent targeted deep sequencing data. Better quality control procedures and strategies that combine results from multiple methods should ensure that higher accuracy is achieved. This is essential to ensure that results from bioinformatics pipelines using Ion Torrent deep sequencing can be robustly applied in cancer research and in the clinic.
wtest: an integrated R package for genetic epistasis testing
Authors: Sun Rui , Xia Xiaoxuan , Chong Ka Chun , Zee Benny Chung-Ying , Wu William Ka Kei , Wang Maggie Haitian
Published: December 2019

Background

With the increasing amount of high-throughput genomic sequencing data, there is a growing demand for a robust and flexible tool to perform interaction analysis. The identification of SNP-SNP, SNP-CpG, and higher order interactions helps explain the genetic etiology of human diseases, yet genome-wide analysis for interactions has been very challenging, due to the computational burden and a lack of statistical power in most datasets.

Results

The wtest R package performs association testing for main effects, pairwise and high order interactions in genome-wide association study data, and cis-regulation of SNP and CpG sites in genome-wide and epigenome-wide data. The software includes a number of post-test diagnostic and analysis functions and offers an integrated toolset for genetic epistasis testing.

Conclusions

The wtest is an efficient and powerful statistical tool for integrated genetic epistasis testing. The package is available in CRAN:https://CRAN.R-project.org/package=wtest.
Microbiome changes: an indicator of Parkinson’s disease?
Authors: Haikal Caroline , Chen Qian-Qian , Li Jia-Yi
Published: December 2019

Parkinson’s disease is characterized by dopaminergic neuron loss and intracellular inclusions composed mainly of alpha synuclein (α-syn), but the mechanism of pathogenesis is still obscure. In recent years, more attention has been given to the gut as a key player in the initiation and progression of PD pathology. Several studies characterizing changes in the microbiome, particularly the gut microbiome, have been conducted. Although many studies found a decrease in the bacterial family Prevotellaceae and in butyrate-producing bacterial genera such as Roseburia and Faecalibacteria, and an increase in the genera Akkermansia many of the studies reported contradictory findings. In this review, we highlight the findings from the different studies and reflect on the future of microbiome studies in PD research.
Power quality disturbance classification based on time-frequency domain multi-feature and decision tree
Authors: Zhao Wenjing , Shang Liqun , Sun Jinfan
Published: December 2019

Accurate classification of power quality disturbance is the premise and basis for improving and governing power quality. A method for power quality disturbance classification based on time-frequency domain multi-feature and decision tree is presented. Wavelet transform and S-transform are used to extract the feature quantity of each power quality disturbance signal, and a decision tree with classification rules is then constructed for classification and recognition based on the extracted feature quantity. The classification rules and decision tree classifier are established by combining the energy spectrum feature quantity extracted by wavelet transform and other seven time-frequency domain feature quantities extracted by S-transform. Simulation results show that the proposed method can effectively identify six types of common single disturbance signals and two mixed disturbance signals, with fast classification speed and adequate noise resistance. Its classification accuracy is also higher than those of support vector machine (SVM) and k-nearest neighbor (KNN) algorithms. Compared with the method that only uses S-transform, the proposed feature extraction method has more abundant features and higher classification accuracy for power quality disturbance.
Comparative effects of crop residue incorporation and inorganic potassium fertilization on soil C and N characteristics and microbial activities in cotton field
Authors: HU Wei , SUI Ning , YU Chaoran , YANG Changqin , LIU Ruixian , ZHOU Zhiguo
Published: December 2019

Background

Crop residue incorporation into the soil is an effective method to augment soil potassium (K) content, and effects of crop residue and K fertilizer on soil K balance have been compared. However, their influences on other soil characteristics such as carbon (C) and nitrogen (N) characteristics and microbial activities have not been quantified. To address this, field experiments were conducted in 2011 at Dafeng (sandy loam) and Nanjing (clay loam) in China with treatments including blank control without crop residue incorporation and K fertilizer application, 0.9 t·ha− 1 wheat straw incorporation (W1C0), 0.7 t·ha− 1 cotton residue incorporation (W0C1), 0.9 t·ha− 1 wheat straw + 0.7 t·ha− 1 cotton residue incorporation (W1C1) and two K fertilizer rates (150 and 300 kg·ha− 1(K2O)) during the cotton season.

Results

Compared with control, K fertilizer treatments did not alter soil water-soluble organic carbon/soil organic carbon (WSOC/SOC) ratio, microbial biomass carbon (MBC)/SOC ratio, MBC/microbial biomass nitrogen (MBN) ratio, water inorganic nitrogen/total nitrogen ratio (WIN/TN), the number of cellulose-decomposing bacteria, or related enzymes activities, however, W0C1, W1C0 and W1C1 treatments significantly increased WSOC/SOC ratio, MBC/SOC ratio and MBC/ MBN ratio, and decreased WIN/TN ratio at both sites. W0C1, W1C0 and W1C1 treatments also increased the number of soil cellulose-decomposing bacteria and activities of cellulase, β-glucosidase and arylamidase. Regarding different crop residue treatments, W1C0 and W1C1 treatments had more significant influences on above mentioned parameters than W0C1 treatment. Moreover, MBC/MBN ratio was the most important factor to result in the differences in the number of cellulose-decomposing bacteria and soil enzymes activities among different treatments.

Conclusions

Short-term K fertilizer application doesn’t affect soil C and N availability and microbial activities. However, crop residue incorporation alters soil C and N characteristics and microbial activities, and the influence of wheat straw is much stronger than that of cotton straw.
Functional MRI in the pre-operative assessment of GI-RADS 3, 4, and 5 ovarian masses
Authors: Ibrahim Rania S. M. , Maher Manar A. E. L. O. , Abdalaziz Solava , Amer Samar , Shafie Doaa , Hamed Soha T.
Published: December 2019

Background

Characterization of an ovarian lesion is a diagnostic challenge. A correct preoperative assessment is of great importance so as to arrange adequate therapeutic procedures. The aim of the current study is to evaluate the diagnostic performance of functional MRI in differentiation between malignant, borderline, and benign ovarian masses.

Results

This study included 56 adnexal lesions. Bilateral synchronous ovarian lesions are detected in 16 cases. Postoperative histologically proved to be benign in 17 (30%), borderline (low potential malignancy) in 12 (22%), and malignant in 27 (48%). The overall diagnostic performance of conventional MRI in the diagnosis of adenexal lesion was a sensitivity of 74%, specificity of 47%, positive predictive value (PPV) of 76%, negative predictive value (NPV) of 44%, and an accuracy of 66%. Functional pelvic MRI examination showed an increase in overall diagnostic performance compared to conventional values with the highest sensitivity of 90% and NPV of 67% using DWI, and the highest specificity of 88%, PPV of 94%, and an accuracy of 82% using DCE MRI.

Conclusion

Functional MRI in conjugation with conventional MRI plays a key role in the ovarian lesion detection, characterization, and staging. Functional MRI is currently being evaluated as possible predictive and prognostic biomarkers in ovarian lesions.
“Choledochoscope” as an Important Addition in Difficult Airway Management: A Case Report
Authors: Poudel Anjali , Pokharel Krishna , Jaisani Mehul Rajesh
Published: December 2019

The choledochoscope is an additional tool to manage a difficult airway. We successfully used it for the first time for awake nasal intubation in a patient with no mouth opening resulting from bilateral temporomandibular ankylosis. The visual appearance of the airway structures was not compromised. However, the shorter length and larger diameter of the choledochoscope in comparison with the fiberoptic bronchoscope are crucial limiting factors of this method. We, therefore, suggest considering a choledochoscope for intubation in patients with difficult airway as a second-line alternative when a fiberoptic bronchoscope is not available.
Epidural-Like Effects With Bilateral Erector Spinae Plane Catheters After Abdominal Surgery: A Case Report
Authors: Pak Aimee , Singh Paramvir
Published: December 2019

This case report highlights the potential for adverse effects with the erector spinae plane (ESP) blocks. ESP blocks are an alternative to the traditional epidural and paravertebral block for postoperative analgesia due to their relative technical ease and seemingly safer profile. To date, few complications have been reported from ESP blocks or catheters. Despite its distance from the epidural space, epidural-like effects may still occur with ESP catheters, such as hypotension and motor blockade, as observed in this patient after abdominal surgery.
Humanistic burden and economic impact of chronic kidney disease: a systematic literature review
Authors: Freeman Caroline , Giles Lucia , Field Polly , Sörstadius Elisabeth , van Haalen Heleen
Published: December 2019

Background: Chronic kidney disease (CKD) is increasing in prevalence worldwide. Progression of CKD to end-stage renal disease (ESRD) can result in the requirement for renal replacement therapy, which incurs considerable healthcare costs and imposes restrictions on patients’ daily living. This systematic review was conducted to inform understanding of the humanistic and economic burden of CKD by collecting quality of life (QoL), symptom burden, and cost and resource use data, with a focus on the impact of disease progression.

Methods: Embase, MEDLINE, the Cochrane Library, and conference proceedings were searched in May 2017 according to predefined inclusion criteria. Data were extracted for full publications reporting either QoL or symptom burden (published 2007–2017; reporting data from ≥ 100 patients) or costs and resource use (published 2012–2017). Relevant QoL studies were those that used the 6-dimension or 8-, 12-, or 36-item Short-Form Health Surveys, 5-dimension EuroQol questionnaire, Healthy Days/Health-Related Quality of Life questionnaire, or Kidney Disease Quality of Life Questionnaire.

Results: Data were extracted from 95 studies reporting QoL data, 47 studies reporting cost and resource use data, and eight studies reporting descriptions of symptoms; 12 studies (seven QoL; five costs/resource use) reported data for patients with and without CKD, and 15 studies (seven QoL; eight costs/resource use) reported data by disease stage. Patients with CKD, including those with ESRD, had worse QoL than those with normal kidney function, and incurred higher healthcare costs. Disease progression was associated with cost increases, particularly for later stages and in patients receiving dialysis. Increasing CKD severity was also associated with reductions in QoL, although not all studies identified showed a consistent decrease with increasing disease stage.

Conclusions: The presence of CKD and CKD progression are associated with reductions in patients’ QoL and increased economic impact. This may be mitigated by interventions that slow progression.
CURRENT TRENDS AND PROBLEMS OF DEVELOPMENT OF THE HOTEL MARKET OF KRASNOYARSK KRAI
Authors: Safronova Tatyana Nikolaevna , Yabrova Olga Alexandrovna , Kamoza Tatyana Leontyevna , Evtukhova Olga Mikhailovna
Published: December 2019

Development of the hotel markets of regions is connected with diversification of a tourist product, search of the new directions. One of major factors of development of regional tourism is change of economic, social, demographic conditions of development of regions. In work socio-economic indexes of Krasnoyarsk krai are presented, statistics of the market of hotel services and tourism for 2014–2018, their structure are analysed. Problems and current trends of development of the tourist and hotel markets of Krasnoyarsk krai are defined.

The purpose – studying of the current state of the hotel market of Krasnoyarsk krai and trends of its development. Within work the following problems were solved: to define the current state of the tourist and hotel markets of Krasnoyarsk krai; to consider the main characteristics of the market and to define trends of its development.

Object of a research were the hotel enterprises of Krasnoyarsk krai.

Work is based on own researches, data of the state statistics.

Research methods: statistical, general scientific methods of the analysis were used.

Results: as a result of the proceeding political instability and decrease in real monetary income of the population the tourist market of Russia changed towards growth of internal tourism that led to growth of the hotel market. Development of the hotel market of Krasnoyarsk krai is connected with diversification of a tourist product, search of the new directions, reduction of average duration of trips, but increase in their frequency.

Scope of results: results of a research can be useful to the regional authorities, specialists of the industry, the students studying in “Hotel business”.
Databases and their security
Authors: Polischuk Yuriy , Borovskiy Aleksandr
Published: December 2019

The tutorial is devoted to the implementation of relational databases. Its purpose is to master the basic principles of design, implementation, maintenance and information security of databases. The manual includes tasks for laboratory work, control questions and tests for self-examination.
Meets the requirements of the Federal state educational standards of higher education of the last generation.
For students of higher educational institutions of all specialties and areas of training, interested in the design, implementation and security of databases.
Maintenance and repair of ship pipelines, valves and filters
Authors: Sherstnev Nikolay
Published: December 2019

The tutorial shows the design features of ship pipelines, valves and filters that affect the conditions of their operation and methods of maintenance and repair. Recommendations for external inspection and control of their elements are given. The features of disassembly and Assembly of various types of valves and filters are shown. With examples from ship practice typical defects of the specified elements, ways of their definition and elimination are considered.
It is intended for students of higher educational institutions (specialization in the specialty "Operation of ship power plants") and University teachers. It can also be used in the system of secondary vocational education in the specialty "Operation of ship power plants".
Struggles with infrastructures of information concerning hospital-to-home transitions
Authors: Norlyk Annelise , Deleuran Cecilia Lykke , Martinsen Bente
Published: December 2019

Homecare nurses play a unique role in providing care during the follow-up after hospital discharge and in preventing readmission. The aim of this study was to explore the key challenges faced by homecare nurses in relation to caring for discharged patients. Data were collected through five focus group interviews with 29 Danish homecare nurses and subjected to inductive content analyses. The key challenges faced by homecare nurses fell into three themes: struggling to see the bigger picture, caring for patients from a distance, and compromising on professionalism. The findings demonstrated a paradox between the need for information and the struggle to access this information due to complicated infrastructures of information-sharing. Homecare nurses took on a substantial responsibility in providing the best possible care despite having limited information. Ironically, by taking on this responsibility, they implicitly contribute to covering up the problems of organisational and professional information flow.
Compassionate care in the community: reflections of a student nurse
Authors: Doran Donna , Phillips Jill , Board Michele
Published: December 2019

Reflecting on practice and analysing situations when compassionate care has been delivered can be a valuable way of helping student nurses develop their understanding of humanising care. This exemplar showcases a scenario when a second-year student nurse studying for a BSc (Honours) in adult nursing explored an experience while working in the community. She critically reflected on an incident highlighting a simple yet powerful example of how she helped an older couple manage an aspect of their care. This exercise helped the student to explore and understand what compassionate care means and highlighted how the value of reflection can be used to gain new insights to enhance the care of older people in her future practice in the community.
Do you have the building blocks for leadership?
Authors: Fowler John
Published: December 2019

Can a dental nurse also be a great manager? John Fowler suggest that the attributes required by both can work well together
An advocate of health
Authors: Nazir Robiha
Published: December 2019

Dental hygienist Robiha Nazir reveals why she signed up to become what she views as a much-needed Mental Health First Aider
The use of quality of life scales for hospice and end-of-life patients
Authors: Flavell Samantha
Published: December 2019

Quality of life scales can be an important tool to the veterinary team. This article explores the use of two quality of life scales, their benefits and limitations using three case studies.
Equine behavioural first aid
Authors: Nellist Jenni
Published: December 2019

It is common for equines to become difficult to handle during procedures, veterinary or otherwise, as a direct result of handling during the procedure and as a consequence of poor mood state derived from inappropriate housing; these lead to pessimistic behavioural responses, which will include proactive defensive behaviour. Since poor equine behaviour is a common cause of injury to veterinary personnel, and not all equine owners and handlers have sufficient levels of competence to cope with dangerous equine behaviour, both the veterinary practice and the client are likely to benefit from veterinary personnel trained and competent in behavioural first aid. Behavioural first aid can prevent problematic behaviour from escalating, protect human safety and improve equine welfare.
Prenatal and Postnatal Clinical Spectrum of a Mosaic Small Supernumerary Marker Chromosome 22
Authors: Tug Esra , Karaoguz Meral Yirmibes , Ergun Mehmet Ali
Published: December 2019

An amniocentesis was performed because of the advanced maternal age at 18 weeks of gestation, and cytogenetic analyses revelaed a de novo mosaic small supernumerary marker chromosome (sSMC), as parental karotypes were normal. Fluorescence in situ hybridization (FISH) analyses with chromosome specific whole chromosome painting, locus, and alphoid satellite DNA probes were ended with the diagnosis of mosaic sSMC of chromosome 22. The result was explained to the family and genetic counselling was given together with the absence of fetal ultrasound findings. The baby was delivered at term by caesarean section. The female neonate with mosaic sSMC did not show any apparent dysmorphic features at birth. No growth and psychomotor retardation were observed at her natal period follow-up. At one year age, she had some mild dysmorphic findings such as high frontal hairline, frontal bossing, thin eyebrows, hypertelorism, flattened tip of nose and prominent philtrum. The reason of the absence of major abnormalities could be related with the presence of heterochromatin region of chromosome 22 rather than the gene rich parts. Finally, this report emphasizes the importance of acting in an analytical algorithm based on chromosomal origin, parental lineage, size and mosaic or non-mosaic status of sSMCs in the prenatal diagnosis, and using FISH technique and postnatal confirmation of the sSMC.
Representative Volume Element Homogenization of a Composite Material by Using Bond-Based Peridynamics
Authors: Xia Wenxuan , Galadima Yakubu Kasimu , Oterkus Erkan , Oterkus Selda
Published: December 2019

This study presents representative volume element (RVE) homogenization by using bond-based peridynamics. First, a method to perform RVE homogenisation analysis with bond-based peridynamic theory is demonstrated. Homogenized material properties of a unit-sized fibre reinforced composite cell with varying fibre volume fraction are predicted using the present method. Peridynamic results are compared against a finite element based RVE approach and a good agreement is observed between the two approaches.
The prevalence and effects of on-call stepdown on orthopaedic registrar training: the North West trainees’ perspective
Authors: Ajwani SH , Biant LC
Published: December 2019

Introduction

Safe staffing levels are increasingly being threatened by gaps in rotas. When a gap occurs in junior grade on-call rotas the orthopaedic registrar needs to step down and undertake the role of both junior and middle-grade doctor. This increased responsibility could compromise the safety and wellbeing of patients and doctors. This study quantifies the prevalence and effects for trainees of stepdown while on call.

Materials and methods

An anonymous online and paper survey of trainees was conducted. The primary outcomes were the prevalence of stepdown in trainees’ experience, the effects of stepdown on trainees and patients, and the overall impact on training and morale.

Results

The response rate was 93% (n = 51). Of the total, 55% of trainees had experienced stepdown, which occurred a minimum of 84 times, statistically more frequently for expected absences rather than unexpected absences (p = 0.002). Of the trainees who stepped down, 64% felt pressure to do so from seniors and 79% from hospital management. Some 50% of trainees felt that step down was managed in an unsafe manner; 40% of trainees stated that stepdown impacted on their own personal safety and 50% of trainees lost a training opportunity. Overall, 57% of trainees considered that stepdown and rota gaps affected their morale negatively. In 85% of cases there were no issues that resulted in patient harm.

Conclusion

The survey results suggest that stepdown is common and it does impact negatively upon registrar training, safety and morale. Patient safety overall seems to be well protected.
Bringing epistemology into intersectional methodology
Authors: Labelle Alexie
Published: December 2019

Since its academic introduction in the late 1980s, the concept of intersectionality has made a staple contribution to feminist scholarship. However, its institutionalised popularity and apparent depoliticisation have led scholars to raise two major concerns: the lack of a clearly defined intersectional methodology; and the erasure of black women scholars in intersectionality scholarship, particularly in the discipline of political science. While the latter rightly addresses epistemology and the politics of knowledge production, the former has lacked a thorough discussion on the ways in which epistemology impacts intersectional methodology, focusing instead on methods and method choice. Drawing on my own experience studying lesbian, gay, bisexual, trans* and queer people of colour activism in Canada, I argue that we need to bring epistemology into intersectional methodology. Hence, this article demonstrates how reflecting on one’s positionality, one’s embodiment of privileges and one’s ethical responsibilities informs the ways in which researchers operationalise intersectional projects, thereby shaping methodology.
Constitutional Job Creation
Authors: Anderson Gary M. , Tollison Robert D.
Published: December 2019

La Costituzione americana viene considerata da mold come un esempio concreto del modo in cui i vincoli costituzionali aH’opportunismo politico abbiano favorito lo sviluppo di un sistema istituzionale nel cui ambito l’economia ha avuto modo di prosperare.

Peraltro, studi recenti hanno sostenuto che le decisioni dei partecipanti alia Convenzione repubblicana del 1787 sono state influenzate dagli interessi che essi rappresentavano. In tal modo è stata riveduta la diffusa opinione secondo cui i costituenti erano persone disinteressate, con il solo obiettivo del bene pubblico.

Un aspetto che in questi studi è stato trascurato riguarda il fatto che questi rappresentanti, che erano prevalentemente ambiziosi, nel disegnare la Costituzione hanno creato una serie di cariche che essi stessi si sono poi candidati ad occupare.

Questo studio costituisce un primo tentativo di analisi di un aspetto sin ora trascurato della storia costituzionale americana. Da esso appare che dei 39 firmatari, ben 32 occuparono importanti posizioni nel governo federale.
Military Conscription, Efficient Policies, and Transfers from the Politically Weak
Authors: Greene Kenneth V. , Balkan Erol
Published: December 2019

Questo scritto mette a confronto differenti teorie economiche sull’arruolamento militare obbligatorio, sottoponendole successivamente a verifica empirica.

Si è sostenuto che, poiché il costo del servizio militare è concentrato su una ristretta base sociale, la maggioranza sarebbe pronta a votare contro la sua eliminazione.

Il contro-argomento è stato che, poiché l’arruolamento obbligatorio è inefficiente, sarebbe invece conveniente eliminarlo. Infatti, con una forte domanda di lavoro e in assenza di guerre si dovrebbe fare minore ricorso all’arruolamento.

Malgrado la varietà delle situazioni concrete, appare che i sistemi democratici sono quelli che maggiormente ricorrono all’arruolamento.

Il problema è quello del confronto tra i costi di efficienza dell’arruolamento e quelli dovuti alle distorsioni prodotte dalle imposte che dovrebbero altrimenti essere prelevate per far fronte alle spese militari.
Local Government without Taxing Authority: A Viable Party Democracy?
Authors: Sørensen Rune J. , Hagen Terje P.
Published: December 2019

Un elemento essenziale della democrazia rappresentativa è il controllo elettorale. Si assume che i votanti mantengano responsabili i governi da loro eletti. La democrazia partitica assume che ogni partito politico rappresenti un distinto programma politico. I cambiamenti nella composizione dei consigli eletti dovrebbero influenzare le politiche perseguite. L’elettorato dovrebbe essere al corrente di queste differenze partitiche ed esprimere la sua soddisfazione o insoddisfazione votando a favore di particolari partiti. Comunemente, si asserisce che queste assunzioni sono violate nella democrazia locale. Ricerche empiriche suggeriscono che la composizione partitica delle assemblee locali non ha conseguenze per le politiche locali di spesa.

Il governo locale norvegese influenza la composizione dei bilanci locali, non la grandezza del reddito locale. Questa analisi rivela che le preferenze di spesa dei consigli locali divergono a seconda della forza di un partito e che i cambiamenti nella rappresentanza locale dei partiti influenzano le effettive politiche di spesa. In aggiunta, i cittadini sembrano avere una qualche conoscenza dei programmi dei partiti. L’insoddisfazione su particolari servizi locali influenza il loro comportamento elettorale, fenomeno che offre almeno parziale supporto empirico all’ipotesi della responsabilità. Questi riscontri ristabiliscono un modesto grado di coerenza tra la rappresentanza partitica locale, lo schema di spesa del governo locale ed il comportamento elettorale.
Parasitical Political Pricing, Economic Calculation, and the Size of Government: Variations on a Theme by Maffeo Pantaleoni
Authors: Wagner Richard E.
Published: December 2019

Il lavoro estende 1’originate intuizione di Maffeo Pantaleoni che vede due distinti meccanismi del prezzo nelle contemporanee economie miste. Da una parte, vi è il meccanismo del prezzo del mercato, caratterizzato da diritti di proprietà esclusivi. Dall’altra, vi è il meccanismo di prezzo del sistema politico, distinto, fra le altre cose, da comitati amministrativi e proprietà comune. Si enfatizza come il sistema di prezzo politico può esistere solo in presenza del mercato ma non viceversa.

Tramite una semplice illustrazione si suggerisce che i «mercati politici» sono parassitari nei confronti di quelli privati. A volte questo parassitismo può essere benefico, come nel caso dei beni pubblici; mentre altre volte è nocivo, come nel caso dei sussidi pubblici che promuovono imprese inefficienti.
The Financing System of the Italian Catholic Church: An Economic Analysis
Authors: Creaco Salvo
Published: December 2019

Prima della revisione del Concordato del 1984, il meccanismo di finanziamento della Chiesa Cattolica Italiana consisteva, da un lato, di un sistema privato, basato su donazioni a carattere volontario e, dall’altro, di un sistema pubblico, con risorse derivanti sia in modo diretto che indiretto dallo Stato.

Il nuovo sistema esclude l’intervento diretto dello Stato e lascia la principale responsabilità per il sostegno economico degli ecclesiastici alia scelta degli individui, sia mediante donazioni non favorite da speciale trattamento fiscale, sia mediante contributi che beneficiano di sgravi fiscali, sia infine mediante assegnazione dell’8 per mille del gettito dell’impostapersonale sul reddito.

L’analisi del nuovo sistema fa prevedere la possibilità di conflitti tra i centri di acquisizione delle entrate, a carattere centrahzzato (Conferenza Episcopale e Istituto per il sostegno del Clero) e i centri di spesa (Diocesi), a carattere decentrato. Tali conflitti potrebbero essere non diversi da quelli che hanno caratterizzato i rapporti tra finanza centrale e finanza locale in Italia.
Effects of working pressure and power on photovoltaic and defect properties of magnetron sputtered Sb2Se3 thin-film solar cells
Authors: Wang Youyang , Li Junda , Chen Yuanjing , Zhou Jianhong , Zhang Jiayan , Mao Wangchen , Zheng Shiqi , Pan Yuhan , Liu Yiqi , Dai Kaijie , Hu Xiaobo , Tao Jiahua , Weng Guoen , Jiang Jinchun , Chen Shaoqiang , Chu Junhao
Published: December 2019

Antimony selenide (

Sb
2

Se
3

) is an emerging material with potential applications in photovoltaics, while magnetron sputtering is an important method in material growth. In this study,

Sb
2

Se
3

thin films, prepared by the magnetron sputtering technique with varied working pressures and sputtering powers, were fabricated into solar cells with a structure of

glass

/

ITO

/

CdS

/

Sb
2

Se
3

/

Au

. The current density versus voltage measurements and x-ray diffraction were introduced to compare the photovoltaic and structural properties of the cell samples. Characterization and identification of the defects in

Sb
2

Se
3

thin films were investigated by admittance measurements. The

Sb
2

Se
3

cell samples prepared with appropriate sputtering power (about 60 W) or working pressure (about 0.4 Pa) were found to own better crystal qualities and lower defect densities, which may be the reason for better efficiency.
Two-point, parallel-beam focused laser differential interferometry with a Nomarski prism
Authors: Bathel Brett F. , Weisberger Joshua M. , Herring Gregory C. , King Rudolph A. , Jones Stephen B. , Kennedy Richard E. , Laurence Stuart J.
Published: December 2019

A Nomarski polarizing prism has been used in conjunction with a focused laser differential interferometer to measure the phase velocity of a density disturbance at sampling frequencies

≥

10

M
H
z

. Use of this prism enables the simultaneous measurement of density disturbances at two closely spaced points that can be arbitrarily oriented about the instrument’s optical axis. The orientation is prescribed by rotating the prism about this axis. Since all four beams (one beam pair at each measurement point) propagate parallel to one another within the test volume, any bias imparted by density fluctuations away from the measurement plane on the disturbance phase velocity is minimized. A laboratory measurement of a spark-generated shock wave and a wind tunnel measurement of a second-mode instability wave on a cone model in a Mach 6 flow are presented to demonstrate the performance of the instrument. High-speed schlieren imaging is used in both cases to verify the results obtained with the instrument.
Quantum cryptography networks in support of path verification in service function chains
Authors: Aguado A. , López D. R. , Pastor A. , López V. , Brito J. P. , Peev M. , Poppe A. , Martín V.
Published: December 2019

Quantum key distribution (QKD) is a physical technology that enables the secure generation of bit streams (keys) in two separated locations. This technology is designed to provide a solution for very secure (quantum-safe) key agreement, which is nowadays at risk due to advances in quantum computing. The recent demonstration of a QKD network in the metropolitan area of Madrid shows how these networks can be deployed in current production infrastructure by following existing networking paradigms, such as software-defined networking. In particular, a three-node QKD network is implemented on the metropolitan area network using existing infrastructure and coexisting with other data and control services. On the other hand, telecommunication networks are drastically changing the way services are architectured. Users of the operator’s infrastructure are moving from traditional connectivity services (e.g., virtual private networks) to a set of interconnected network functions, either physical or virtual, in the shape of service function chaining (SFC). However, SFC users do not have a method to validate that the traffic flow is appropriately forwarded across the nodes in the network, a situation that may lead to very critical security breaches (e.g., a security node or a firewall in the chain that is bypassed). This work presents a method for validating ordered proof-of-transit (OPoT) on top of the Madrid Quantum Network. We first provide a general description of the QKD network deployed in Madrid. Then, we describe an existing security protocol for PoT in packet networks, analyzing its issues and vulnerabilities. Finally, this work presents a protocol for alleviating the security breach found in this work and for providing OPoT in SFC. Finally, an example of the real implementation is shown, where nodes being part of the OPoT scheme are provisioned with QKD-derived keys.
Nanoparticle–laser interaction: computation of size reduction and thermal conductance at solid–vapor interface
Authors: Movahedinejad Hadi , Nadjari Hamid , Farahbod A. H.
Published: December 2019

Laser interaction with a water-immersed metal nanoparticle can bring about a condition such that a bubble is generated and the nanoparticle is evaporated. This phenomenon is strongly dependent on the laser parameters and the nanoparticle size. In this study, we simulate the behavior of a gold nanoparticle and its surrounding medium during interaction with a nanosecond-pulsed laser by considering nanoparticle size reduction, variations in the nanoparticle absorption cross section, and variations in thermal conductance at the nanoparticle–bubble interface. Results show that the bubble dynamics under a low-energy and long-pulse-width laser (so that it does not cause evaporation) strongly depends on the nanoparticle temperature behavior, while under higher laser energy, it is dependent on the amount of nanoparticle size reduction. Moreover, by comparing the nanoparticle thermal behavior with experimental data, we are able to estimate the thermal conductance at the nanoparticle–bubble interface. This simulation not only leads to nanoparticle size control but also helps in understanding the heat transfer processes at nanoscale.
Simultaneous laser-driven x-ray and two-photon fluorescence imaging of atomizing sprays
Authors: Guénot D. , Svendsen K. , Björklund Svensson J. , Ekerfelt H. , Persson A. , Lundh O. , Berrocal E.
Published: December 2019

In this Letter, we report for the first time, to the best of our knowledge, the possibility of visualizing an atomizing spray by simultaneously recording x-ray absorption and two-photon laser-induced fluorescence imaging. This unique illumination/detection scheme is made possible due to the use of soft x rays emitted from a laser-driven x-ray source. An 800 mJ laser pulse of 38 fs duration is used to generate an x-ray beam with up to

4
×

10
8

photons ranging from 1 to 10 keV, allowing projection radiography of water jets generated by an automotive port fuel injector. In addition, a fraction of the laser pulse (

∼

10

m
J

) is employed to form a light sheet and to induce two-photon fluorescence in a dye added to the water. The resulting high-contrast fluorescence images provide fine details of the spray structure, with reduced blur from multiple light scattering, while the integrated liquid mass is extracted from the x-ray radiography. In this proof of principle, we show that the combination of these two highly complementary techniques, in both the visible and soft x-ray regimes, is very promising for future characterization of challenging spray, as well as for further understanding of the physics of liquid atomization.
Water window soft x-ray source enabled by a 25  W few-cycle 2.2 µm OPCPA at 100  kHz
Authors: Pupeikis J. , Chevreuil P.-A. , Bigler N. , Gallmann L. , Phillips C. R. , Keller U.
Published: December 2019

Coherent soft x-ray (SXR) sources enable fundamental studies in the important water window spectral region. Until now, such sources have been limited to repetition rates of 1 kHz or less, which restricts count rates and signal-to-noise ratio for a variety of experiments. SXR generation at high repetition rate has remained challenging because of the missing high-power infrared laser sources to drive the high-harmonic generation (HHG) process. Here we present an optical parametric chirped pulse amplifier (OPCPA) centered at a wavelength of 2.2 µm and generating 16.5 fs pulses (2.2 oscillation cycles of the carrier wave) with 25 W of average power and a peak power exceeding 14 GW at 100 kHz pulse repetition rate. This corresponds to the highest reported peak power for high-repetition-rate long-wavelength laser systems. The output of this 2.2 µm OPCPA system was used to generate a coherent SXR radiation extending beyond 0.6 keV through HHG in a high-pressure gas cell.
Large-scale optical phased array using a low-power multi-pass silicon photonic platform
Authors: Miller Steven A. , Chang You-Chia , Phare Christopher T. , Shin Min Chul , Zadka Moshe , Roberts Samantha P. , Stern Brian , Ji Xingchen , Mohanty Aseema , Jimenez Gordillo Oscar A. , Dave Utsav D. , Lipson Michal
Published: December 2019

Optical phased arrays are a promising beam-steering technology for ultra-small solid-state lidar and free-space communication systems. Long-range, high-performance arrays require a large beam emission area densely packed with thousands of actively phase-controlled, power-hungry light emitting elements. To date, such large-scale phased arrays have been impossible to realize since current demonstrated technologies would operate at untenable electrical power levels. Here we show a multi-pass photonic platform integrated into a large-scale phased array that lowers phase shifter power consumption by nearly 9 times. The multi-pass structure decreases the power consumption of a thermo-optic phase shifter to aPπof1.7mW/πwithout sacrificing speed or optical bandwidth. Using this platform, we demonstrate a silicon photonic phased array containing 512 actively controlled elements, consuming only 1.9 W of power while performing 2D beam steering over a70∘×6∘field of view. Our results demonstrate a path forward to building scalable phased arrays containing thousands of active elements.