bluuebunny/crossref_metadata_2025 huggingface dataset:
A Practice‐Based Research Database to Study Perinatal Nurse Home Visiting to Pregnant Women With Diabetes
Authors: Bloch Joan R. , McKeever Amy E. , Zupan Susan K. , Birati Yosefa , Chiatti Beth , Devido Jessica A. , Maldonado Linda T. , Geller Pamela A. , Barkin Jennifer L.
Published: January 2019

Background and Aims

Accumulation of real‐world evidence from practice‐based perinatal nurse home visits to pregnant women with diabetes prompted this translational perinatal health disparities research. Given the global diabetes epidemic, this academic–community partnered research team is studying the utilization, processes, and outcomes of this understudied model of perinatal nurse home visiting that provide home‐based enhanced diabetes care to pregnant women. Because the nursing records provide the rich source of data for the study, our aim is to provide an in‐depth description of the Philadelphia Pregnancy and Diabetes Home Visiting (PPD‐HV) research database developed from data in the longitudinal nursing records.

Methods

This descriptive study uses retrospective data abstracted from paper‐based perinatal nurse home visiting clinical records to create the PPD‐HV, a HIPAA compliant, secure REDCap electronic research database. The sample includes 248 urban, pregnant women with diabetes who received a total of 1,644 home visits during the year 2012. The setting was Philadelphia, a large metropolitan city in the northeastern part of the United States. The PPD‐HV database followed the information fields of the paper‐based clinical nursing forms, which were originally designed by following the Omaha System to guide documenting the nursing process used in caring for patients in their homes.

Results

Using REDCap, the PPD‐HV research database is robust with 239 variables and captures longitudinal clinical nursing data. Among the pregnant women with diabetes receiving nurse home visits, the mean age was 30.7 years, most were single, and had given birth to other children.

Linking Evidence to Action

Real‐world clinical nursing practice data provide a rich source of research data to advance understandings about this model of enhanced diabetes care and the pregnant women with diabetes receiving the care. Considering the global epidemic of diabetes, this is a perinatal nurse home visiting model to replicate and evaluate.
Examination of Talent Selection Methods in Different Sports Branches
Authors: Kaynar Ömer , Bilici Fatih
Published: January 2019

The purpose of this study was to determine the talent selection methods applied to athletes involved in different sports branches in Turkey. The research population consisted of 724 volunteer athletes who were active in sports clubs in thirty seven different cities of Turkey. Semi-structured interview form was used as data collection tool. It was determined that no talent test was applied to 512 (70.72%) of 724 athletes who participated in the study and 212 (29.28%) were put to talent test methods by their coaches. Of 212 athletes who were put to talent test, 41 (5.66%) were observed for their physical characteristics, 59 (8.14%) for their competitions, 75 (10.35%) for their basic motor skills (speed, strength, endurance, coordination, balance, flexibility and agility) and 37 (5.11%) for their technical capacities in competitions. As a result; it is estimated that the application of physical, mental, physiological, body composition and genetic tests all together while determining the talent selection in sports will be the most effective method to detect talented athletes.
The Relationship of Shooting Skill with Functional Movement Performance and Attention Level of Basketball Players
Authors: Canlı Umut , Koçak Çalık Veli
Published: January 2019

The purpose of this study was to determine the relationship of shooting skill with the functional performances and attention levels of professional basketball players. Sixteen male basketball players (age = 20.6 ± 2.30) from university basketball team who were trained on regular basis participated in this study as volunteers. Participants' body height and body weight were measured and body mass indexes were calculated. D2 test of attention was utilized to determine the focus levels. Shooting skills were determined by shooting tests. Spearman Correlation Analysis was utilized to determine the correlation of shooting skill with functional movement performances and attention levels of participants. There was a moderate level of negative correlation (rho = -0.57; p<0.05) between the shooting skill scores and deep squat scores which is one of the functional movement performances. A moderate level of positive correlation (rho = 0.54; p<0.05) between TN-E (Total number of items processed-Total error score) scores and shooting skill scores were determined. Consequently, as the deep squat values of professional basketball players increases, the shooting skill decreases and with the increasing attention level, shooting skill increases.
The Role of Psychological Hardiness on Performance of Scissors Kick
Authors: Sivrikaya M. Haluk
Published: January 2019

The main purpose of this study was to find the effect of psychological hardiness on performance of scissors kick in football. The present research was practical in terms of purpose and correlation in term of nature. The statistical population of research was Ataturk University female students (18-24 yrs old) unfamiliar to football scissors kick, in 2018. So, 28 participants were selected randomly based on Morgan Table from 30 vulenteers. In this study, two quastionnars of hardiness and Charbonneau sport performance were used to collect data. To test hypotheses, regression test was used. In this research, SPSS 20 software was used in all calculations and tests.The results showed that psychological hardiness play a significant role on performance of scissors kick.  It is one of the most important characteristics of a successful athlete.
Determination of the Perceptions of Sport Managers on the Concept of Organization: A Metaphor Analysis Study
Authors: Kurtipek Serkan , Gungor Nuri Berk
Published: January 2019

This research aims to determine the perceptions of sports managers on the concept of organization with the help of metaphors. The sample of study consists of 45 sports managers. In order to collect data in the study, "metaphor form" was prepared to determine the perceptions of the sport managers on the concept of organization. In the metaphor form, the sport managers were asked to complete the sentence "Organization is like.....; because........". In the study, phenomenological design, one of the from qualitative research approaches was used. In the analysis of the data, content analysis technique was used. The reliability coefficient for the inter-participants was calculated for the reliability of the analysis of the research data and this value was found to be 91%. With the evaluation of the data, it was seen that sport managers produced a total of 34 metaphors. These metaphors were collected in 4 different categories. These are respectively "being systematic", "management", "purpose" and "division of labor". The most produced metaphors by sports managers are family, car, human body, and puzzle. Living, lifeless, abstract and concrete metaphors were generally used for the concept of organization.
Validity and Reliability Study of Turkish Version of Number Sense Screener for Children Aged 72-83 Months
Authors: Aktulun Özgün Uyanık
Published: January 2019

The objective of this study is to perform a validity and reliability examination of Number Sense Screener (NSS) by applying it to Turkish children aged 72-83 months. The universe of this general survey model study was constituted by 72-83-month old children showing normal development and studying at primary schools under the authority of the Ministry of National Education in central Afyonkarahisar province, Turkey. In sample selection, primary schools with different socioeconomic levels (low, medium, and high) were determined by taking into account the representation capability of the universe in Afyonkarahisar province, Turkey, and 672 children were selected from these schools through systematic sampling method. Validity and reliability studies were carried out using data from the NSS application. In light of the performed analyses, the difficulty and discrimination indexes of the items of NSS have been determined to range between 0.38 and 0.97, and 0.16 and 0.64, respectively. The reliability coefficients calculated for the whole of NSS have been determined to be between .876 and .884. The infit and outfit statistics of the items of NSS have been concluded to be extremely good. In DIF analysis performed in order to determine whether the items of NSS are gender-biased, the scale items have been concluded to be unbiased.
A history of ASA standards
Authors: Blaeser Susan , Struck Christopher J.
Published: January 2019

The Acoustical Society of America's involvement in and support of standards development work, both national and international, is perhaps its major outward-facing program, serving the needs of government, industry, and academia, as well as the needs of its members. Since its inception, the Acoustical Society of America has included the development of acoustical standards as one of the main elements of its mission. The standards published by ASA provide a trusted source of technical information to people both within and outside of ASA's membership. This article recounts the historical development of the ASA Standards Program and provides background information on key developments that have shaped its course, and influenced the direction of the Society itself.
Convolutional neural network for detecting odontocete echolocation clicks
Authors: Luo Wenyu , Yang Wuyi , Zhang Yu
Published: January 2019

In this work, a convolutional neural network based method is proposed to automatically detect odontocetes echolocation clicks by analyzing acoustic data recordings from a passive acoustic monitoring system. The neural network was trained to distinguish between click and non-click clips and was subsequently converted to a full-convolutional network. The performance of the proposed network was evaluated using synthetic data and real audio recordings. The experimental results indicate that the proposed method works stably with echolocation clicks of different species.
Compliance and Practical Utility of Continuous Wearing of activPAL™ in Adolescents
Authors: Shi Yan , Huang Wendy Yajun , Yu Jane Jie , Sheridan Sinead , Sit Cindy Hui-Ping , Wong Stephen Heung-Sang
Published: January 2019

Purpose: The aim of this study was to examine the factors that influence compliance and practical utility of a continuous wear protocols for activPAL™ among adolescents. Methods: Seven hundred and fifty-five (11–18 y; 50.6% girls) students wore the waterproof activPAL™ for 7 consecutive days. The effects of factors such as weather and practical strategies on compliance were assessed. Students were asked to note reasons for removing it in a log. After the 7-day period, students anonymously completed a practical utility questionnaire. Results: The final sample used to analyze compliance contained 588 available data points; 72.4% met the validity criteria, which were ≥4 valid days. Rainfall was inversely associated with total wear time, whereas using alcohol pads and cartoon stickers during the application were positively associated with total wear time. Sweating (25.2%) and skin irritation (39.0%) were the most reasons for 290 removal episodes by 235 students. The 131 questionnaires showed that 80.1% regarded the continuous wear period as too long and encountered problems, and 55% would rather not wear it again. Conclusion: Rainy weather affected girls’ compliance with the continuous wear protocol for activPAL™. Skin irritation and sweat-induced inadvertent drops caused removal. Future studies should investigate more user-friendly protocols.
Tropical uplift may set Earth's thermostat
Authors: Voosen Paul
Published: January 2019

Indonesia's mountains could be cause of current glacial age.
Spotting evolution among us
Authors: Gibbons Ann
Published: January 2019

The half-million people in the UK Biobank hold the genetic legacy of Neanderthals—and clues to how we are still evolving.
The Little Ice Age and 20th-century deep Pacific cooling
Authors: Gebbie G. , Huybers P.
Published: January 2019

Deep Pacific cooling

Earth's climate cooled considerably across the transition from the Medieval Warm Period to the Little Ice Age about 700 years ago. Theoretically, owing to how the ocean circulates, this cooling should be recorded in Pacific deep-ocean temperatures, where water that was on the surface then is found today. Gebbie and Huybers used an ocean circulation model and observations from both the end of the 19th century and the end of the 20th century to detect and quantify this trend. The ongoing deep Pacific is cooling, which revises Earth's overall heat budget since 1750 downward by 35%.

Science
, this issue p.
70
Dynamic response and hydrodynamics of polarized crowds
Authors: Bain Nicolas , Bartolo Denis
Published: January 2019

A crowd that flows like water

The behavior of large numbers of insects, animals, and other flocks is often based on rules about individual interactions. Bain and Bartolo applied a fluid-like model to the behavior of marathon runners as they walked up to the start line of the Chicago Marathon (see the Perspective by Ouellette). They observed nondamping linear waves with the same speed for different starting corrals of runners and at different races around the world. Their model should apply both to this type of polarized crowd as well as to other groups, which may help guide crowd management.

Science
, this issue p.
46
; see also p.
27
H3K9me3-heterochromatin loss at protein-coding genes enables developmental lineage specification
Authors: Nicetto Dario , Donahue Greg , Jain Tanya , Peng Tao , Sidoli Simone , Sheng Lihong , Montavon Thomas , Becker Justin S. , Grindheim Jessica M. , Blahnik Kimberly , Garcia Benjamin A. , Tan Kai , Bonasio Roberto , Jenuwein Thomas , Zaret Kenneth S.
Published: January 2019

Reversing chromatin dynamics for development

Compacted chromatin regions, marked by trimethylation of histone H3 at position lysine 9 (H3K9me3), occur at highly repeated DNA sequences, helping to suppress recombination and gene expression. Because pluripotent cells contain low levels of H3K9me3 heterochromatin relative to differentiated cells, it has been thought that an increase in such heterochromatin helps to define cell differentiation. Nicetto
et al.
used two independent methods to examine compacted heterochromatic domains and found that H3K9me3 compaction increased at protein-coding genes during early mouse organogenesis. During differentiation, these domains open up to allow cell-specific expression. Loss of heterochromatin by genetic inactivation of the H3K9me3 methyltransferases caused ectopic expression of cell-inappropriate genes and tissue pathology.

Science
, this issue p.
294
Rovibrational quantum state resolution of the C
60
fullerene
Authors: Changala P. Bryan , Weichman Marissa L. , Lee Kevin F. , Fermann Martin E. , Ye Jun
Published: January 2019

C
60
at high resolution

It generally takes more energy for molecules to vibrate than to rotate. A vibrational absorption band thus encompasses many distinct concurrent rotational transitions, but these tend to blur together when the molecules have more than a few atoms. Changala
et al.
succeeded in cooling C
60
fullerenes sufficiently to obtain rotational resolution within a C–C stretching band. Success hinged on careful optimization of argon buffer gas flow. Such quantum state–resolved features could aid characterization of fullerene-type compounds in exotic environments such as interstellar space.

Science
, this issue p.
49
Fluorine-programmed nanozipping to tailored nanographenes on rutile TiO
2
surfaces
Authors: Kolmer M. , Zuzak R. , Steiner A. K. , Zajac L. , Engelund M. , Godlewski S. , Szymonski M. , Amsharov K.
Published: January 2019

Nanographenes on oxides

The growth of nanographene islands and ribbons on metal surfaces can be accomplished on single-crystal metal surfaces through carbon-carbon coupling reactions, but the surfaces of oxides do not assist these reactions. Kolmer
et al.
show that fluorinated aryl groups can be coupled to form nanographenes on the rutile surface of titanium oxide. The fluorine substitution of the aryl groups was selected so that as the carbon-fluorine bonds were thermally activated, a stepwise process sequentially added aromatic rings around a central aryl group until it was completely substituted.

Science
, this issue p.
57
From voluntary commitments to ocean sustainability
Authors: Neumann Barbara , Unger Sebastian
Published: January 2019

A common pledge and review system is needed
Examining author gender data
Authors: Berg Jeremy
Published: January 2019

I previously reported results of a study on author gender in
Science
(
science.sciencemag.org/content/355/6323/329
) that was based on the examination of a random sample of approximately 2600 authors for which gender was inferred by painstaking analysis of websites and similar sources. Unfortunately, this approach does not scale well to large samples necessary for many analyses. We have since initiated systematic efforts to examine gender distributions of key populations of authors and reviewers for the
Science
family of journals using additional data and tools and plan to use this information to guide policy development and other appropriate steps to address any gender disparities.
Prevalence of rheumatoid arthritis in relation to serum cadmium concentrations: cross-sectional study using Korean National Health and Nutrition Examination Survey (KNHANES) data
Authors: Joo Sang Hyun , Lee Joongyub , Hutchinson David , Song Yeong Wook
Published: January 2019

Objectives

It has been suggested that exposure to heavy metal cadmium (Cd) may contribute to a high risk of developing rheumatoid arthritis (RA). This study was to investigate the association of RA prevalence and serum concentrations of Cd and other heavy metals through large survey data analysis.

Design

A retrospective cross-sectional survey study.

Setting

Large population survey in Korea.

Participants

53 829 subjects participated in Korean National Health and Nutrition Examination Survey (KNHANES) from 2008 to 2013.

Interventions

Heavy metals were measured in different time periods of the survey programme which resulted in three different data sets for analysis: Cd, mercury (Hg) and lead (Pb) from 2008 to 2012 survey; serum manganese (Mn) and urine arsenic (As) from 2008 to 2009 survey; and serum zinc (Zn) from 2010 survey. RA prevalence and its associations with serum heavy metals were analysed using a general linear/logistic regression model of complex sample design.

Results

Serum Cd was elevated in patients with RA (RA vs control: 1.30±0.07 µg/L vs 1.17±0.01 µg/L, p<0.01). There were no significant differences in urine levels of As or serum levels of Pb, Hg, Mn or Zn between patients with RA and controls. OR (95% CI) of RA prevalence according to 1 µg/L increase of serum Cd level was 1.28(95% CI 1.03 to 1.61). Prevalence of RA in women was increased with increasing quartiles of Cd levels, with a 19-fold difference in female RA prevalence between individuals in the lowest quartile of serum Cd level and those in the highest quartile (0.18% vs 3.42%). Cubic spline curve of prevalence OR showed increased risk of RA according to increased serum Cd level. Increased risk of RA in men was not observed with increased serum Cd levels.

Conclusion

There was an increased prevalence of RA in females associated with increased serum levels of Cd in the Korean population.
Investigating a therapist-guided, parent-assisted remote digital behavioural intervention for tics in children and adolescents—‘Online Remote Behavioural Intervention for Tics’ (ORBIT) trial: protocol of an internal pilot study and single-blind randomised controlled trial
Authors: Hall Charlotte Lucy , Davies E Bethan , Andrén Per , Murphy Tara , Bennett Sophie , Brown Beverley J , Brown Susan , Chamberlain Liam , Craven Michael P , Evans Amber , Glazebrook Cristine , Heyman Isobel , Hunter Rachael , Jones Rebecca , Kilgariff Joseph , Marston Louise , Mataix-Cols David , Murray Elizabeth , Sanderson Charlotte , Serlachius Eva , Hollis Chris
Published: January 2019

Introduction

Tourette syndrome and chronic tic disorder are common, disabling childhood-onset conditions. Guidelines recommend that behavioural therapy should be offered as first-line treatment for children with tics. However, there are very few trained behaviour therapists for tics and many patients cannot access appropriate care. This trial investigates whether an internet-delivered intervention for tics can reduce severity of symptoms.

Methods and analysis

This parallel-group, single-blind, randomised controlled superiority trial with an internal pilot will recruit children and young people (aged 9–17 years) with tic disorders. Participants will be randomised to receive 10 weeks of either online, remotely delivered, therapist-supported exposure response prevention behavioural therapy for tics, or online, remotely delivered, therapist-supported education about tics and co-occurring conditions. Participants will be followed up mid-treatment, and 3, 6, 12 and 18 months post randomisation.

The primary outcome is reduction in tic severity as measured on the Yale Global Tic Severity Scale total tic severity score. Secondary outcomes include a cost-effectiveness analysis and estimate of the longer-term impact on patient outcomes and healthcare services. An integrated process evaluation will analyse quantitative and qualitative data in order to fully explore the implementation of the intervention and identify barriers and facilitators to implementation. The trial is funded by the National Institute of Health Research (NIHR), Health Technology Assessment (16/19/02).

Ethics and dissemination

The findings from the study will inform clinicians, healthcare providers and policy makers about the clinical and cost-effectiveness of an internet delivered treatment for children and young people with tics. The results will be submitted for publication in peer-reviewed journals. The study has received ethical approval from North West Greater Manchester Research Ethics Committee (ref.: 18/NW/0079).

Trial registration numbers

ISRCTN70758207andNCT03483493; Pre-results.
Lean and mean? Associations of level of performance, chronic injuries and BMI in sport climbing
Authors: Grønhaug Gudmund
Published: January 2019

Objectives

To assess possible associations between performance level (achieved level of difficulty), chronic injuries and body mass index (BMI) in sport climbing.

Method

Retrospective survey.

Setting

Web-based questionnaire.

Participants

667 active climbers (385 reported having chronic injuries).

Outcome measure

BMI, performance level in sport climbing, onset of a climbing-related injury, preferred style of climbing, education, gender.

Statistics

Descriptive statistics and general linear model(GLM) performed with SPSS V.25 for windows.

Result

No associations were found between level of performance in sport climbing, onset of a climbing-related injury, preferred style of climbing, education, gender and BMI.

Conclusion

BMI is not associated with climbing-related chronic injury or level of performance in climbing. The average BMI of climbers up to the elite level is similar to that of a lower rate of performance.

Clinical relevance

The findings in this study suggest that there is no need for maintaining a low BMI to be able to reach elite levels in climbing.
Use of Web 2.0 tools and social media for continuous professional development among primary healthcare practitioners within the Defence Primary Healthcare: a qualitative review
Authors: Willman Antony Sean
Published: January 2019

Introduction

Alongside traditional attendance at learning, general practitioners use social media and Web 2.0 tools in the UK for continuous professional development (CPD). Research has demonstrated, however, barriers to their uptake and use, as well as a requirement for training. Primary care doctors working for the Defence Primary Healthcare (DPHC) use similar technologies, but it is not known what factors affect the uptake. This qualitative research aimed to explore the knowledge and attitudes of this demographic further.

Methods

An online questionnaire was distributed to DPHC doctors via email and a social networking service (SNS) tool. Questions included demographic and open free-text response boxes. These were subjected to thematic analysis to identify initial concepts subsequently grouped into categories.

Results

DPHC doctors are already using Web 2.0 and social media for education. The benefits of convenience are recognised, but protected time is required to maximise impact. They also identified attendance at learning events, better quality information technology (IT) and further training as important enablers for their CPD.

Conclusions

The results reaffirmed previous findings that while there is engagement with online learning and Web 2.0 technologies, training in Web 2.0 use and substandard IT infrastructure were barriers to greater uptake. Attended learning events are also popular due to the peer-to-peer networking that takes place, but also as they allow protected time out of the office. The use of Web 2.0 for CPD and of SNS should be given equal status to allow the development of a DPHC doctors’‘community of practice’.
Guerin’s sign reflecting pterygoid plate dysjunction
Authors: Sahni Vaibhav
Published: January 2019

A case of panfacial trauma is reported comprising of multiple facial fractures and a clearly evident Guerin’s sign along with an oronasal communication. The case reinforces the importance of recognising this sign and its classical presentation.
Cytoskeletal control of nuclear morphology and stiffness are required for OPN-induced bone-marrow-derived mesenchymal stem cell migration
Authors: Liu Lingling , Luo Qing , Sun Jinghui , Song Guanbin
Published: January 2019

During cell migration, the movement of the nucleus must be coordinated with the cytoskeletal dynamics that influence the efficiency of cell migration. Our previous study demonstrated that osteopontin (OPN) significantly promotes the migration of bone-marrow-derived mesenchymal stem cells (BMSCs). However, the mechanism that regulates nuclear mechanics of the cytoskeleton during OPN-promoted BMSC migration remains unclear. In this study, we investigated how the actin cytoskeleton influences nuclear mechanics in BMSCs. We assessed the morphology and mechanics of the nuclei in the OPN-treated BMSCs subjected to disruption or polymerization of the actin cytoskeleton. We found that disruption of actin organization by cytochalasin D (Cyto D) resulted in a decrease in the nuclear projected area and nuclear stiffness. Stabilizing the actin assembly with jasplakinolide (JASP) resulted in an increase in the nuclear projected area and nuclear stiffness. SUN1 (Sad-1/UNC-84 1) is a component of the LINC (linker of nucleoskeleton and cytoskeleton) complex involved in the connections between the nucleus and the cytoskeleton. We found that SUN1 depletion by RNAi decreased the nuclear stiffness and OPN-promoted BMSC migration. Thus, the F-actin cytoskeleton plays an important role in determining the morphology and mechanical properties of the nucleus. We suggest that the cytoskeletal–nuclear interconnectivity through SUN1 proteins plays an important role in OPN-promoted BMSC migration.
HISCC behavior of SUS301L-MT stainless steel laser-arc hybrid welding joints
Authors: Fu Z. H. , Li T. , Mei M. L. , Gou G. Q. , Zhu Z. Y. , Ma C. P. , Gao W. , Hu Y. C.
Published: January 2019

The hydrogen-induced stress corrosion cracking (HISCC) behavior of SUS301L-MT stainless steel laser-arc hybrid welding (LAHW) joints was investigated using slow strain rate tensile (SSRT) method in 3.5 wt.% NaCl solution under different cathodic potentials. With the negative shift of applied potentials from open circle potential (OCP) to −1400 mV[Formula: see text], the HISCC susceptibility index ([Formula: see text]) decreased from 0.15 (OCP) to 0.06 (−400 mV[Formula: see text]), then increased to 0.28 (−1400 mV[Formula: see text]). The specimens tested in air and under OCP to −800 mV ruptured in weld metal zone with ductile features of dimples. While with the potential turned more negative, the specimens ruptured in base metal zone with brittle features of transgranular cleave in martensite, intergranular failure and secondary cracks [Chen et al., Int. J. Adv. Manuf. Technol. 73, 1695 (2014)].
Effect of charging hydrogen on the tensile properties of A7N01 aluminum alloy friction stir welded joints
Authors: Ma Chuanping , Kang Guozheng , Gou Guoqing , Chen Hui , Che Xiaoli
Published: January 2019

A7N01 aluminum alloy is widely used in rail transit industry due to its excellent comprehensive mechanical properties. However, due to its sensitivity to stress corrosion cracking (SCC), especially in hydrogen-containing moisture environment, the mechanical properties of hydrogen-charged A7N01 aluminum alloy friction stir welding (FSW) joints were tested through the tensile testing machine. The scanning electron microscopy (SEM) was used to study the tensile fracture morphology. The results indicate that the ductility and tensile strength loss of A7N01 Al alloy FSW joints are large in conditions of charging hydrogen. This is due to the embrittlement of the material caused by hydrogen infiltrating into the grain boundary of the aluminum alloy material.
EMPIRICAL ANALYSIS OF BITCOIN PRICES USING THRESHOLD TIME SERIES MODELS
Authors: MAGTANGGOL III DE GUZMAN RODOLFO ANGELO , SO MIKE K. P.
Published: January 2019

This paper proposes the use of threshold heteroskedastic models which integrate threshold nonlinearity [Tong, H (1978). On a Threshold Model, pp. 575–586. Netherlands: Sijthoff & Noordhoff; Tong, H and KS Lim (1980). Threshold autoregression, limit cycles and cyclical data. Journal of the Royal Statistical Society. Series B (Methodological), 3, 245–292.] and GARCH-type conditional variance for modeling Bitcoin returns to provide an understanding on the huge volatility that Bitcoin has been famous for. Specifically, the model attempts to identify different regimes throughout the history of Bitcoin using the different available Bitcoin network characteristics, such as cost per transaction, number of transactions per block, number of active addresses and number of transactions. Estimation and diagnostic checks are performed using Markov chain Monte Carlo methods. In the empirical analysis, we show that our model is able to identify periods of crashes as one of these regimes, which is also a period of declining returns and declining number of active users. We also find that the number of users and the number of transactions determine the magnitude or persistence of a crash period.
Carbon, carbides, carbonates and carbonatitic melts in the Earth's interior
Authors: Stagno Vincenzo
Published: January 2019

Over recent decades, many experimental studies have focused on the effect of CO
2
on phase equilibria and melting behaviour of synthetic eclogites and peridotites as a function of pressure and temperature. These studies have been of fundamental importance to understanding the origin of carbonated magmas varying in composition from carbonatitic to kimberlitic. The occurrence of diamonds in natural rocks is further evidence of the presence of (reduced) carbon in the Earth's interior. The oxygenation of the Earth's interior (i.e. its redox state) through time has strongly influenced the speciation of carbon from the mantle to mantle-derived magmas and, in turn, to the volcanic gases released to the atmosphere. This paper explains how the knowledge of the oxygen fugacity recorded by mantle rocks and determined through the use of appropriate oxy-thermobarometers allows modelling of the speciation of carbon in the mantle, its mobilization in the asthenospheric mantle by redox partial melting, and its sequestration and storage during subduction by redox freezing processes. The effect of a gradual increase of the mantle
f
O
2
on the mobilization of C is here discussed along with the main variables affecting its transport by subduction into the mantle.
No Silver Bullet Reloaded
Authors: Fraser Steven , Mancl Dennis
Published: January 2019

At XP2017 in Köln, a panel was convened to discuss the classic 1987 IEEE Software paper by Frederick P. Brooks, "No Silver Bullet: Essence and Accidents in Software Engineering." The ideas presented in his paper have influenced several generations of software developers. Brooks emphasized the notions of essential complexity and accidental complexity, and he offered suggestions for promising approaches to software development. While his approaches are linked to what we now recognize as "agile practices," panelists offered an implicit caveat that they must be done with discipline to avoid increased accidental complexity. Panelists also observed that agile development itself is not a "silver bullet".
Software Engineering for Smart Cyber-Physical Systems
Authors: Bures Tomas , Weyns Danny , Schmer Bradley , Fitzgerald John
Published: January 2019

Smart Cyber-Physical Systems (sCPS) are a novel kind of Cyber- Physical Systems engineered to take advantage of large-scale cooperation between devices, users and environment to achieve added value in face of uncertainty and various situations in their environment. Examples of sCPS include modern traffic systems, Industry 4.0 systems, systems for smart-buildings, smart energy grids, etc. The uniting aspect of all these systems is that to achieve their high-level of intelligence, adaptivity and ability to optimize and learn, they heavily rely on software. This makes them software-intensive systems, where software becomes their most complex part. Engineering sCPS thus becomes a recognized software engineering discipline, which however, due to specifics of sCPS, can only partially rely on the existing body of knowledge in software engineering. In fact, it turns out that many of the traditional approaches to architecture modeling and software development fail to cope with the high dynamicity and uncertainty of sCPS. This calls for innovative approaches that jointly reflect and address the specifics of such systems. This paper maps the discussions and results of the Third International Workshop on Software Engineering for Smart Cyber-Physical Systems (SEsCPS 2017), which specifically focuses on challenges and promising solutions in the area of software engineering for sCPS.
Constructing quotient inductive-inductive types
Authors: Kaposi Ambrus , Kovács András , Altenkirch Thorsten
Published: January 2019

Quotient inductive-inductive types (QIITs) generalise inductive types in two ways: a QIIT can have more than one sort and the later sorts can be indexed over the previous ones. In addition, equality constructors are also allowed. We work in a setting with uniqueness of identity proofs, hence we use the term QIIT instead of higher inductive-inductive type. An example of a QIIT is the well-typed (intrinsic) syntax of type theory quotiented by conversion. In this paper first we specify finitary QIITs using a domain-specific type theory which we call the theory of signatures. The syntax of the theory of signatures is given by a QIIT as well. Then, using this syntax we show that all specified QIITs exist and they have a dependent elimination principle. We also show that algebras of a signature form a category with families (CwF) and use the internal language of this CwF to show that dependent elimination is equivalent to initiality.
Abstraction-safe effect handlers via tunneling
Authors: Zhang Yizhou , Myers Andrew C.
Published: January 2019

Algebraic effect handlers offer a unified approach to expressing control-flow transfer idioms such as exceptions, iteration, and async/await. Unfortunately, previous attempts to make these handlers type-safe have failed to support the fundamental principle of modular reasoning for higher-order abstractions. We demonstrate that abstraction-safe algebraic effect handlers are possible by giving them a new semantics. The key insight is that code should only handle effects it is aware of. In our approach, the type system guarantees all effects are handled, but it is impossible for higher-order, effect-polymorphic code to accidentally handle effects raised by functions passed in; such effects tunnel through the higher-order, calling procedures polymorphic to them. By contrast, the possibility of accidental handling threatens previous designs for algebraic effect handlers. We prove that our design is not only type-safe, but also abstraction-safe. Using a logical-relations model that we prove sound with respect to contextual equivalence, we derive previously unattainable program equivalence results. Our mechanism offers a viable approach for future language designs aiming for effect handlers with strong abstraction guarantees.
Intersection types and runtime errors in the pi-calculus
Authors: Dal Lago Ugo , de Visme Marc , Mazza Damiano , Yoshimizu Akira
Published: January 2019

We introduce a type system for the π-calculus which is designed to guarantee that typable processes are
well-behaved
, namely they never produce a run-time error and, even if they may diverge, there is always a chance for them to “finish their work”, i.e., to reduce to an idle process. The introduced type system is based on non-idempotent intersections, and is thus very powerful as for the class of processes it can capture. Indeed, despite the fact that the underlying property is Π
2
0
-complete, there is a way to show that the system is
complete
, i.e., that any well-behaved process is typable, although for obvious reasons infinitely many derivations need to be considered.
Principality and approximation under dimensional bound
Authors: Dudenhefner Andrej , Rehof Jakob
Published: January 2019

We develop an algebraic and algorithmic theory of principality for the recently introduced framework of intersection type calculi with dimensional bound. The theory enables inference of principal type information under dimensional bound, it provides an algebraic and algorithmic theory of approximation of classical principal types in terms of computable bases of abstract vector spaces (more precisely, semimodules), and it shows a systematic connection of dimensional calculi to the theory of approximants. Finite, computable bases are shown to span standard principal typings of a given term for sufficiently high dimension, thereby providing an approximation to standard principality by type inference, and capturing it precisely for sufficiently large dimensional parameter. Subsidiary results include decidability of principal inhabitation for intersection types (given a type does there exist a normal form for which the type is principal?). Remarkably, combining bounded type inference with principal inhabitation allows us to compute approximate normal forms of arbitrary terms without using beta-reduction.
Sound and complete bidirectional typechecking for higher-rank polymorphism with existentials and indexed types
Authors: Dunfield Jana , Krishnaswami Neelakantan R.
Published: January 2019

Bidirectional typechecking, in which terms either synthesize a type or are checked against a known type, has become popular for its applicability to a variety of type systems, its error reporting, and its ease of implementation. Following principles from proof theory, bidirectional typing can be applied to many type constructs. The principles underlying a bidirectional approach to indexed types (generalized algebraic datatypes) are less clear. Building on proof-theoretic treatments of equality, we give a declarative specification of typing based on focalization. This approach permits declarative rules for coverage of pattern matching, as well as support for first-class existential types using a focalized subtyping judgment. We use refinement types to avoid explicitly passing equality proofs in our term syntax, making our calculus similar to languages such as Haskell and OCaml. We also extend the declarative specification with an explicit rules for deducing when a type is principal, permitting us to give a complete declarative specification for a rich type system with significant type inference. We also give a set of algorithmic typing rules, and prove that it is sound and complete with respect to the declarative system. The proof requires a number of technical innovations, including proving soundness and completeness in a mutually recursive fashion.
Gradual typing: a new perspective
Authors: Castagna Giuseppe , Lanvin Victor , Petrucciani Tommaso , Siek Jeremy G.
Published: January 2019

We define a new, more semantic interpretation of gradual types and use it to ``gradualize'' two forms of polymorphism: subtyping polymorphism and implicit parametric polymorphism. In particular, we use the new interpretation to define three gradual type systems ---Hindley-Milner, with subtyping, and with union and intersection types--- in terms of two preorders, subtyping and materialization. We define these systems both declaratively ---by adding two subsumption-like rules--- which yields clearer, more intelligible, and streamlined definitions, and algorithmically by reusing existing techniques such as unification and tallying.
Modalities, cohesion, and information flow
Authors: Kavvos G. A.
Published: January 2019

It is informally understood that the purpose of modal type constructors in programming calculi is to control the flow of information between types. In order to lend rigorous support to this idea, we study the category of classified sets, a variant of a denotational semantics for information flow proposed by Abadi et al. We use classified sets to prove multiple noninterference theorems for modalities of a monadic and comonadic flavour. The common machinery behind our theorems stems from the the fact that classified sets are a (weak) model of Lawvere's theory of axiomatic cohesion. In the process, we show how cohesion can be used for reasoning about multi-modal settings. This leads to the conclusion that cohesion is a particularly useful setting for the study of both information flow, but also modalities in type theory and programming languages at large.
Familial monads and structural operational semantics
Authors: Hirschowitz Tom
Published: January 2019

We propose a categorical framework for structural operational semantics, in which we prove that under suitable hypotheses bisimilarity is a congruence. We then refine the framework to prove soundness of bisimulation up to context, an efficient method for reducing the size of bisimulation relations. Finally, we demonstrate the flexibility of our approach by reproving known results in three variants of the π-calculus.
Bindings as bounded natural functors
Authors: Blanchette Jasmin Christian , Gheri Lorenzo , Popescu Andrei , Traytel Dmitriy
Published: January 2019

We present a general framework for specifying and reasoning about syntax with bindings. Abstract binder types are modeled using a universe of functors on sets, subject to a number of operations that can be used to construct complex binding patterns and binding-aware datatypes, including non-well-founded and infinitely branching types, in a modular fashion. Despite not committing to any syntactic format, the framework is ``concrete'' enough to provide definitions of the fundamental operators on terms (free variables, alpha-equivalence, and capture-avoiding substitution) and reasoning and definition principles. This work is compatible with classical higher-order logic and has been formalized in the proof assistant Isabelle/HOL.
Better late than never: a fully-abstract semantics for classical processes
Authors: Kokke Wen , Montesi Fabrizio , Peressotti Marco
Published: January 2019

We present Hypersequent Classical Processes (HCP), a revised interpretation of the “Proofs as Processes” correspondence between linear logic and the π-calculus initially proposed by Abramsky [1994], and later developed by Bellin and Scott [1994], Caires and Pfenning [2010], and Wadler [2014], among others. HCP mends the discrepancies between linear logic and the syntax and observable semantics of parallel composition in the π-calculus, by conservatively extending linear logic to hyperenvironments (collections of environments, inspired by the hypersequents by Avron [1991]). Separation of environments in hyperenvironments is internalised by ⊗ and corresponds to parallel process behaviour. Thanks to this property, for the first time we are able to extract a labelled transition system (lts) semantics from proof rewritings. Leveraging the information on parallelism at the level of types, we obtain a logical reconstruction of the delayed actions that Merro and Sangiorgi [2004] formulated to model non-blocking I/O in the π-calculus. We define a denotational semantics for processes based on Brzozowski derivatives, and uncover that non-interference in HCP corresponds to Fubini’s theorem of double antiderivation. Having an lts allows us to validate HCP using the standard toolbox of behavioural theory. We instantiate bisimilarity and barbed congruence for HCP, and obtain a full abstraction result: bisimilarity, denotational equivalence, and barbed congruence coincide.
Distributed programming using role-parametric session types in go: statically-typed endpoint APIs for dynamically-instantiated communication structures
Authors: Castro David , Hu Raymond , Jongmans Sung-Shik , Ng Nicholas , Yoshida Nobuko
Published: January 2019

This paper presents a framework for the static specification and safe programming of message passing protocols where the number and kinds of participants are dynamically instantiated.

We develop the first theory of distributed multiparty session types (MPST) to support parameterised protocols with indexed roles—our framework statically infers the different kinds of participants induced by a protocol definition as role variants, and produces decoupled endpoint projections of the protocol onto each variant. This enables safe MPST-based programming of the parameterised endpoints in distributed settings: each endpoint can be implemented separately by different programmers, using different techniques (or languages). We prove the decidability of role variant inference and well-formedness checking, and the correctness of projection.

We implement our theory as a toolchain for programming such role-parametric MPST protocols in Go. Our approach is to generate API families of lightweight, protocol- and variant-specific type wrappers for I/O. The APIs ensure a well-typed Go endpoint program (by native Go type checking) will perform only compliant I/O actions w.r.t. the source protocol. We leverage the abstractions of MPST to support the specification and implementation of Go applications involving multiple channels, possibly over mixed transports (e.g., Go channels, TCP), and channel passing via a unified programming interface. We evaluate the applicability and run-time performance of our generated APIs using microbenchmarks and real-world applications.
Quantum relational Hoare logic
Authors: Unruh Dominique
Published: January 2019

We present a logic for reasoning about pairs of interactive quantum programs – quantum relational Hoare logic (qRHL). This logic follows the spirit of probabilistic relational Hoare logic (Barthe et al. 2009) and allows us to formulate how the outputs of two quantum programs relate given the relationship of their inputs. Probabilistic RHL was used extensively for computer-verified security proofs of classical cryptographic protocols. Since pRHL is not suitable for analyzing quantum cryptography, we present qRHL as a replacement, suitable for the security analysis of post-quantum cryptography and quantum protocols. The design of qRHL poses some challenges unique to the quantum setting, e.g., the definition of equality on quantum registers. Finally, we implemented a tool for verifying proofs in qRHL and developed several example security proofs in it.