bluuebunny/crossref_metadata_2025 huggingface dataset:
Currarino Triad: Importance of Preoperative Magnetic Resonance Imaging
Authors: AbouZeid Amr AbdelHamid , Mohammad Shaimaa Abdelsattar , Seada Mohammad , Khiamy Khaled , Gamal Radwa
Published: November 2019

Currarino triad is a rare syndrome that may be occasionally encountered during managing cases of anorectal anomalies. The triad consists of anorectal anomaly, sacral bony defect, and a presacral mass. It may be familial or sporadic, with a reported female predominance. Identification of the characteristic notched sacrum (sacral scimitar) in plain X-ray (anteroposterior view) is considered the key for the diagnosis; however, not infrequently, this radiological sign is overlooked, especially with a small sacral defect.

Excision of the presacral cyst is usually performed concomitantly during anorectoplasty. The prone position is the standard approach for posterior sagittal anorectoplasty (PSARP) in males; however, in females, the supine position can be used as an alternative (anterior sagittal anorectoplasty). In this case report, excision of the presacral cyst took place in two steps: the first excision during the PSARP procedure in the prone position, and a second operation in the supine lithotomy position to remove a residual component of the lesion that was missed during the primary operation. It was clear that the supine lithotomy position provided better access to explore the presacral space than the prone position, especially with a deeply located cyst as in our case. The role of magnetic resonance imaging (MRI) in the identification of the exact nature and extent of the lesion before surgery is crucial and should be performed in all cases.
Splenic Rupture Secondary to Vascular Ehlers–Danlos Syndrome Managed by Coil Embolization of the Splenic Artery
Authors: Kamalanathan Keisha C. , Barnacle Alex M. , Holbrook Charlotte , Rees Clare
Published: November 2019

Aim Atraumatic splenic rupture is uncommon and life-threatening. It may be related to underlying pathology and be the initial manifestation of the condition. Vascular Ehlers–Danlos syndrome (V-EDS) is a rare autosomal dominant collagen vascular disorder, associated with vessel fragility and rupture. We describe a child presenting with splenic rupture managed by embolization of the splenic artery. She was subsequently diagnosed with V-EDS.

Case Description A 11-year-old girl with thalassemia trait presented with sudden onset of abdominal pain and hypovolemic shock. There was no history of trauma. Following resuscitation, abdominal computed tomography showed hemoperitoneum and active splenic arterial extravasation. Angiography demonstrated four bleeding points, from irregular vessels supplying the upper two-thirds of the spleen. These were not amenable to supraselective embolization. Therefore, coil embolization of the main splenic artery was performed, with no splenic supply seen on the postembolization angiogram. Her postoperative recovery was complicated by pancreatitis secondary to partial ischemia of the pancreatic tail. Subsequent extensive investigations excluded hematological, myeloproliferative, and infective causes for her splenic rupture. A safeguarding investigation was completed, with no pertinent factors identified. Findings of thin skin, abnormal bruising, and hypermobile joints raised a clinical suspicion of a connective tissue disorder. Genetic testing revealed a de novo mutation of the COL3A1 gene.

Conclusions There are only four reports of V-EDS causing splenic rupture in the literature to date. These patients were all adults and only one had not previously been diagnosed with V-EDS. All underwent splenectomy. While V-EDS presenting with abdominal visceral rupture in children has been reported, this is the first report of a child with V-EDS presenting with splenic rupture. It is the only case of splenic rupture secondary to V-EDS that has been managed minimally invasively by embolization.
Antibiotics for 3rd and 4th Degree Vaginal Lacerations, Uterine Tamponade, and Manual Placental Extraction
Authors: Stern-Ascher Conrad N. , Huang Yongmei , Duffy Cassandra R. , Andrikopoulou Maria , Wright Jason D. , Goffman Dena , D'Alton Mary E. , Friedman Alexander M.
Published: November 2019

Objective Trends in use of antibiotics during delivery hospitalizations complicated by (1) 3rd/4th degree vaginal lacerations, (2) manual placenta extraction, and (3) uterine tamponade are not well characterized. The objective of this study was to analyze trends in antibiotic use during vaginal delivery hospitalizations complicated by these three clinical scenarios.

Study Design An administrative inpatient database was used to perform a serial cross-sectional analysis of antibiotic administration during delivery hospitalizations in the United States from January 2006 to March 2015. The primary outcome was receipt of antibiotics during vaginal delivery hospitalizations complicated by (1) 3rd and 4th degree vaginal lacerations, (2) manual placenta extraction, and (3) uterine tamponade. Patients with other indications for antibiotics were excluded. The Cochran–Armitage test was used to assess trends. Adjusted log linear regression analyses including demographic, hospital, and obstetric factors were performed to analyze factors associated with antibiotic receipt for each of these three clinical scenarios in both primary and sensitivity analyses.

Results From 2006 to 2015 the rate of antibiotic administration during delivery hospitalizations decreased from 43.1% in 2006 to 25.5% for 3rd and 4th degree lacerations and from 59.6% to 49.2% for manual extraction (p < 0.01). Administration of antibiotics in the setting of uterine tamponade decreased from 48.6% in 2006 to 27.6% in 2009 before rising to 62.5% in the first quarter of 2015. In adjusted analyses, comparing the first quarter of 2015 to 2006 adjusted risk ratios for antibiotic administration were 0.61 (95% confidence interval [CI] 0.56–0.66) for 3rd and 4th degree vaginal lacerations, 0.76 (95% CI 0.53–1.09) for manual placental extraction, and 0.83 (95% CI 0.76–0.92) for uterine tamponade.

Conclusion Antibiotics are not used consistently during vaginal deliveries complicated by 3rd/4th degree lacerations, manual placenta extraction, and uterine tamponade. These findings support that a significant opportunity exists for comparative effectiveness research to assist in characterizing best practices.
Male-to-Female Ratios, Race/Ethnicity, and Spontaneous Preterm Birth among 11 Million California Infants
Authors: Shaw Gary M. , Mayo Jonathan A. , Eisenberg Michael L. , Catalano Ralph , Stevenson David K.
Published: November 2019

Objective An observed disparity in population-scale data are a larger number of males among preterm births (PTBs). We investigated spontaneous PTB risk among women of various race/ethnic groups in combination with infants' sex.

Study Design This observational study was conducted in > 10 million California births (1991–2012) using birth certificates linked with maternal and infant hospital discharge data.

Results Male-to-female ratios among term (37–42 weeks) infants exhibited the narrow ratio range 1.02 to 1.06 across race/ethnic groups. Such ratios among spontaneous PTBs were generally larger for all race/ethnic groups except non-Hispanic blacks. For blacks, ratios tended to be lower and similar to their term birth counterpart, 1.03. Hazard ratios adjusted for maternal age and education for non-Hispanic blacks were 0.99 (95% confidence interval [CI] 0.90–1.09), 1.01 (95% CI 0.95–1.08), 0.98 (95% CI 0.94–1.03), and 1.03 (95% CI 1.01–1.05), respectively, for gestational week groupings of 20 to 23, 24 to 27, 28 to 321, and 32 to 36. Hazard ratios for non-Hispanic whites for the same groupings were 1.08 (95% CI 0.98–1.18), 1.13 (95% CI 1.07–1.19), 1.21 (95% CI 1.17–1.25), and 1.18 (95% CI 1.17–1.19).

Conclusion Why male-to-female ratios are similar across gestational ages in blacks but substantially higher in other race/ethnic groups is theoretically considered relative to inflammation, stress, and other influences.
2 Mechanistic Aspects of Carbon—Boron Bond Formation
Authors: Carbó J. J. , Maseras F.
Published: November 2019

Mechanisms for the selective formation of carbon–boron bonds under mild reaction conditions can be better understood with the help of computational studies, either alone or in collaboration with experimental research. There is a diversity of reaction mechanisms, many of which can be effectively characterized with currently available techniques.
4 Synthesis of gem-Diboron Compounds from Diboron Reagents
Authors: Ping Y. , Wu C. , Wang J.
Published: November 2019

gem-Diboron compounds are important intermediates in organic synthesis. In recent decades, a variety of methods for the preparation of gem-diboron compounds have been developed, among which, insertion into B–B bonds represents a unique approach. This chapter summarizes the synthesis of gem-diboron compounds based on insertion reactions into diboron compounds. These reactions include the diborylation of gem-dibromides, alkenes, benzylic C–H bonds, carbonyls, carbamates, and diazo compounds.
6 Borylation of Carbonyl and Imine Groups
Authors: Clark T. B. , Cho H. Y.
Published: November 2019

The nucleophilic borylation of carbonyl groups and imines provides α-oxy and α-amino boronate esters, respectively, under a variety of metal-catalyzed and metal-free reaction conditions. The resulting boronate esters, which can be accessed in high enantiopurity, have been utilized in a variety of transformations based on the reactivity of the carbon–boron bond. For α-oxy boronate esters, the oxygen or boron is often protected for increased stability. Formation of carbon–carbon bonds by homologation reactions and Suzuki–Miyaura-type coupling reactions provides advanced intermediates in synthesis. A variety of methods have been developed for the asymmetric synthesis of α-amino boronate esters, a key precursor to the α-amino boronic acid pharmacophore. Application of these methods to the synthesis of bortezomib and a precursor to (R)-cetirizine have been demonstrated.
7 Borylative Ring Opening
Authors: Pineschi M. , Boldrini C.
Published: November 2019

This review describes published methods for the direct introduction of a boron atom into organic molecules by ring opening of strained cyclic systems using nucleophilic diboron species. Considering the synthetic versatility of functionalized organoboron derivatives, the newly formed carbon–boron bond thus installed paves the way for a wide range of useful subsequent transformations.
8 Borylative Ring Closing
Authors: Kubota K. , Ito H.
Published: November 2019

This chapter reviews metal-catalyzed and boron-mediated borylative ring-closing reactions of unsaturated substrates that offer efficient routes to a wide variety of boron-functionalized carbo- and heterocyclic compounds.
9 Decarbonylative/Decarboxylative Borylation
Authors: Xu L.
Published: November 2019

Organoboron species are versatile building blocks and have been widely used in the synthesis of bioactive molecules, natural products, and organic materials. Accordingly, approaches to access such compounds have been widely explored. Carboxylic acids, which are ubiquitous and abundant organic feedstocks, can be transformed into their borylated counterparts via several different catalytic or stoichiometric approaches. In this review, decarboxylative borylation reactions, which form a carbon–boron bond with elimination of carbon dioxide, are detailed in terms of reaction conditions, substrate scope, and experimental procedures.
10 Borylation Reactions in Water
Authors: Kitanosono T. , Kobayashi S.
Published: November 2019

Organoboron compounds are integral to modern synthetic organic chemistry as their C–B linkages undergo a range of chemical transformations. Their privileged position is underpinned by their versatile transformability with retention of stereochemistry, as well as their non-toxic nature and excellent functional-group tolerance. Although water has become a common medium in the reaction of organoboron compounds, such as Suzuki–Miyaura couplings, C–B bond formations in aqueous media have emerged only recently. This chapter offers an overview of recent developments across the broad landscape of organoboron chemistry, using solvent amounts of water and covering a range of C–B bond-formation processes, including enantioselective reactions.
11 Nanocatalyzed Borylation Reactions
Authors: Geetharani K. , Bose S. K.
Published: November 2019

Nanocatalyzed organoboron synthesis is currently a topic of significant interest as it overcomes some of the limitations of homogeneous catalyst systems. This chapter focuses on the use of nanoparticles to catalyze carbon–boron bond-formation reactions via different approaches including diboration and hydroboration of C–C multiple bonds as well as C–H and C–X (X = Br, I) borylation reactions.
12 Reactions through Radical Boryl Moieties
Authors: Zhang F.-L. , Wang Y.-F.
Published: November 2019

Recent synthetic applications of boryl radical moieties, including reduction reactions and the synthesis of organoboron compounds, are reviewed in this chapter. A specific focus is given to discussion of the methodology, applicability, and experimental details.
13 Boron “Ate” Complexes for Asymmetric Synthesis
Authors: Aiken S. G. , Bateman J. M. , Aggarwal V. K.
Published: November 2019

Addition of a nucleophile to a boronic ester results in the generation of a tetravalent boronate “ate” complex. If there is a leaving group stationed on the carbon atom α to the boron atom, the boronate complex can undergo stereospecific 1,2-migration with simultaneous expulsion of the leaving group to form a homologated boronic ester. The enantioselectivity of the process is dictated by either incorporating a chiral substituent into the boronic ester component (substrate control), or by forming a boronate complex through the addition of an enantioenriched carbenoid species to a boronic ester (reagent control). Activation of a boronic ester with organolithium reagents generates a nucleophilic boronate complex that acts as a chiral organometallic-type reagent, reacting with a wide range of electrophiles with inversion of stereochemistry. This chapter discusses methodology available for the enantioselective homologation of boronic esters using both substrate- and reagent-controlled strategies, and the development of boronate complexes as chiral nucleophiles.
14 Application of Selective Asymmetric Borylation to Target Compounds
Authors: Gong T.-J. , Ahmed E.-A. M. A. , Fu Y.
Published: November 2019

This chapter describes recent progress in the use of transition-metal-catalyzed asymmetric borylation (asymmetric hydroboration, diboration, and borylative difunctionalization) for the preparation of enantioenriched chiral boronate ester derivatives, and for the synthesis of α- and β-aminoboronates. Moreover, selected applications of these asymmetric borylation protocols to the synthesis of biologically active compounds and natural products are presented.
Social behavior for autonomous vehicles
Authors: Schwarting Wilko , Pierson Alyssa , Alonso-Mora Javier , Karaman Sertac , Rus Daniela
Published: November 2019

Significance

We present a framework that integrates social psychology tools into controller design for autonomous vehicles. Our key insight utilizes Social Value Orientation (SVO), quantifying an agent’s degree of selfishness or altruism, which allows us to better predict driver behavior. We model interactions between human and autonomous agents with game theory and the principle of best response. Our unified algorithm estimates driver SVOs and incorporates their predicted trajectories into the autonomous vehicle’s control while respecting safety constraints. We study common-yet-difficult traffic scenarios: highway merging and unprotected left turns. Incorporating SVO reduces error in predictions by 25%, validated on 92 human driving merges. Furthermore, we find that merging drivers are more competitive than nonmerging drivers.
Resolving titin’s lifecycle and the spatial organization of protein turnover in mouse cardiomyocytes
Authors: Rudolph Franziska , Hüttemeister Judith , da Silva Lopes Katharina , Jüttner René , Yu Lily , Bergmann Nora , Friedrich Dhana , Preibisch Stephan , Wagner Eva , Lehnart Stephan E. , Gregorio Carol C. , Gotthardt Michael
Published: November 2019

Significance

Building and maintaining sarcomeres is a tremendous challenge for the myocyte. This includes expression of the giant protein titin, assembly of the premyofibril, integration of titin into the sarcomere lattice, and remodeling under load with elimination of aged sarcomeric proteins. It is still unclear how titin synthesis and sarcomere assembly are orchestrated, how titin is integrated into the sarcomere, and how working sarcomeres afford constant remodeling, as they need to exchange titin proteins at the end of their lifetime. Here, we use a dual fluorophore knockin mouse that allows us to simultaneously follow titin’s N and C termini in vivo and study titin integration into the developing and mature sarcomere as well as sarcomere remodeling and disassembly.
Chromosome disentanglement driven via optimal compaction of loop-extruded brush structures
Authors: Brahmachari Sumitabha , Marko John F.
Published: November 2019

Significance

Topology simplification of chromosomes occurs simultaneously with their segregation during cell division and is driven by interplay between chromosome compaction and topology fluctuations. Loop extrusion, a mechanism of genome organization where DNA/chromatin loops are actively extruded to form a cylindrical polymer “brush,” has been proposed as a mechanism underlying chromosome folding and compaction. In this study, we show that such a brush model possesses an optimal loop size that simultaneously maximizes lengthwise compaction and minimizes interchromosomal entanglement. Our model predicts the optimal loop size and other experimentally observable properties of chromosomes for a wide range of organisms of varied genome size.
Single-molecule imaging of HIV-1 envelope glycoprotein dynamics and Gag lattice association exposes determinants responsible for virus incorporation
Authors: Pezeshkian Nairi , Groves Nicholas S. , van Engelenburg Schuyler B.
Published: November 2019

Significance

To create an infectious HIV-1 particle, the envelope glycoprotein (Env) must find a budding virus assembly site on the surface of an infected cell. Assembly sites are composed of growing 2-dimensional lattices of the structural Gag protein anchored to the plasma membrane by the matrix domain. The cytoplasmic tail of Env and the matrix domain are physically proximal on the inner leaflet of the membrane, placing these elements in direct contact upon encounter. We provide single-molecule evidence that the Env cytoplasmic tail and a single residue in matrix are necessary for lattice retention of Env, with membrane budding being dispensable. This supports a model for direct interaction or corralling of Env by the matrix domain and suggests that a druggable interface exists.
The conical shape of DIM lipids promotes
Mycobacterium tuberculosis
infection of macrophages
Authors: Augenstreich Jacques , Haanappel Evert , Ferré Guillaume , Czaplicki Georges , Jolibois Franck , Destainville Nicolas , Guilhot Christophe , Milon Alain , Astarie-Dequeker Catherine , Chavent Matthieu
Published: November 2019

Phthiocerol dimycocerosate (DIM) is a major virulence factor of the pathogen
Mycobacterium tuberculosis
(
Mtb
). While this lipid promotes the entry of
Mtb
into macrophages, which occurs via phagocytosis, its molecular mechanism of action is unknown. Here, we combined biophysical, cell biology, and modeling approaches to reveal the molecular mechanism of DIM action on macrophage membranes leading to the first step of
Mtb
infection. Matrix-assisted laser desorption ionization time-of-flight (MALDI-TOF) mass spectrometry showed that DIM molecules are transferred from the
Mtb
envelope to macrophage membranes during infection. Multiscale molecular modeling and
31
P-NMR experiments revealed that DIM adopts a conical shape in membranes and aggregates in the stalks formed between 2 opposing lipid bilayers. Infection of macrophages pretreated with lipids of various shapes uncovered a general role for conical lipids in promoting phagocytosis. Taken together, these results reveal how the molecular shape of a mycobacterial lipid can modulate the biological response of macrophages.
Distinct metabolic adaptation of liver circadian pathways to acute and chronic patterns of alcohol intake
Authors: Gaucher Jonathan , Kinouchi Kenichiro , Ceglia Nicholas , Montellier Emilie , Peleg Shahaf , Greco Carolina Magdalen , Schmidt Andreas , Forne Ignasi , Masri Selma , Baldi Pierre , Imhof Axel , Sassone-Corsi Paolo
Published: November 2019

Binge drinking and chronic exposure to ethanol contribute to alcoholic liver diseases (ALDs). A potential link between ALDs and circadian disruption has been observed, though how different patterns of alcohol consumption differentially impact hepatic circadian metabolism remains virtually unexplored. Using acute versus chronic ethanol feeding, we reveal differential reprogramming of the circadian transcriptome in the liver. Specifically, rewiring of diurnal SREBP transcriptional pathway leads to distinct hepatic signatures in acetyl-CoA metabolism that are translated into the subcellular patterns of protein acetylation. Thus, distinct drinking patterns of alcohol dictate differential adaptation of hepatic circadian metabolism.
Arousal regulates frequency tuning in primary auditory cortex
Authors: Lin Pei-Ann , Asinof Samuel K. , Edwards Nicholas J. , Isaacson Jeffry S.
Published: November 2019

Significance

Changes in brain state modulate how information is processed in sensory cortical areas. Here we use population imaging and intracellular recording to show that arousal regulates frequency tuning in layer 2/3 of primary auditory cortex. Increased arousal reduces lateral inhibition, broadens frequency tuning and enhances cortical representations of pure tones. Despite the arousal-dependent reduction in stimulus selectivity, frequency discrimination by cell ensembles improves due to a reduction in correlated variability (noise correlations).
Extensive free-energy simulations identify water as the base in nucleotide addition by DNA polymerase
Authors: Roston Daniel , Demapan Darren , Cui Qiang
Published: November 2019

Significance

The microscopic chemical mechanism of adding a base to a growing strand of DNA during DNA replication is unknown. The chemistry requires multiple proton transfers in a complex active site, and experimental probes have been unable to distinguish among the many plausible reaction pathways. This work uses an efficient computational approach to systematically survey the many plausible chemical mechanisms for the reaction and concludes that a water molecule in the active site plays a crucial role. The work also clarifies the catalytic role played by a controversial third metal cation that appeared in the active site during crystallographic studies. The new mechanistic understanding will guide studies of medically and technologically vital questions on DNA replication, gene expression, and gene editing.
Identification of Reg3β-producing cells using IL-22-stimulated enteroids
Authors: Sato Mika , Inaba Akihiko , Iwatsuki Ken , Saito Yuki , Tadaishi Miki , Shimizu Makoto , Kobayashi-Hattori Kazuo
Published: November 2019

Reg3β, a lectin, displays antibacterial activity. This study investigated Reg3β-expressing cells using IL-22-stimulated enteroids. IL-22 stimulation elevated the mRNA and protein levels of Reg3β. IL-22 also increased the mRNA levels of CD133 (a transit-amplifying cell marker) and lysozyme (a Paneth cell marker). Immunohistochemistry showed partial colocalization of Reg3β- and lysozyme-positive cells, suggesting that Paneth cells are one of Reg3β-producing cells.
Audiological and psychological profiles of children with tinnitus
Authors: Raj-Koziak Danuta , Bieńkowska Katarzyna , Gos Elżbieta , Włodarczyk Elżbieta , Skarżyński Henryk , Skarżyński Piotr Henryk
Published: November 2019

Purpose:

The objective of the study was to gauge the audiological and psychological profiles of children with tinnitus.

Method:

We recruited 25 paediatric patients (aged less than 18 years) reporting tinnitus who voluntarily came to our clinic in 2017. The children and their parents underwent a structured interview as part of a consultation in the Tinnitus Department. Otolaryngological examination and tonal and impedance audiometry were performed. Children filled in a Visual Analogue Scale (VAS) on loudness, annoyance, and how well they were coping with their tinnitus. Additionally, we used the Revised Children's Anxiety and Depression Scale and the Revised Children Anxiety and Depression Scale (Parent Version) to look for possible depressive and anxiety disorders, and the EAS Temperament Survey to assess the temperament of the children.

Results:

The group consisted of 25 children (16 girls and 9 boys) aged from 6 to 16 years. Most of the children had normal hearing. Tinnitus had a significant daily impact on sleeping, studying, and leisure. The VAS scale results revealed that younger children, 6 to 10 years old, found tinnitus more troublesome than older children (11 to 16 years). No child with tinnitus showed any severe symptoms of depression or anxiety. All showed average levels of temperamental traits, close to normative values.

Conclusion:

When diagnosing tinnitus in children it is important to recognize that tinnitus affects children differently to adults. Whether children with tinnitus require specific intervention remains a difficult question to answer. Hence, there is an urgent need to devise a questionnaire that can assess the impact of tinnitus on children’s quality of life.
The use Instagram with visiting interest: The correlation between the use @littlecollins.bdg Instagram with visiting interest
Authors: Ahmadi D , Adzhani A V
Published: November 2019

In this research the aim was to determine how far of the influence of using social media Instagram with visiting interest. As done by one Instagram of one of the new restaurants in Bandung that is Cafe Little Collins and have Instagram that is @littlecollins.bdg. In this research, researchers used a quantitative approach and using correlational studies. The results indicate the correlation between the use of Instagram with visiting followers’ interest is a significant correlation. Because the data collection technique used was a questionnaire with 95 respondents and a literature study relevant for this research. After the data collected then performed analysis and hypothesis test using Spearman Rho ranks correlation.
Utilization of information technology for sustainable rural development
Authors: Chaerowati D L , Ibrahim I S
Published: November 2019

This paper presents the utilization of information and communication technology in a rural community in Indonesia, which experiences a development gap caused by structural constraints and lack of infrastructure. The paper based on field research by taking the case of a village called Mandalamekar in Tasikmalaya, West Java, which uses information technology as a tool of struggle for rural development. This study refers to the concept of sustainable rural development using case study research with data collection techniques in the forms of interviews, observation, and document studies. This paper discusses the society of using information technology and the variety of ITs applied in the rural development. Since the rural community took advantage of information technology, the acceleration of transformation took place on ability to build and operate the technology and media as its main tool. This paper proves that IT can be effective tools for sustainable rural development. IT not only influences how people interacts each other, but at the same time, it affects how people find mutual solutions for rural problems.
A preliminary study of bit-integer hash function for bilinear pairing identity-based cryptosystem
Authors: Saputra D E
Published: November 2019

Hash function is a crucial part of identity-based cryptosystem, especially for identity-based cryptosystem that utilize bilinear pairing as its core mechanism. However, the hash function has specific requirement that most of commonly known function are not suitable for this purpose, especially the requirement that requires the output length of function is varies. A variable length hash function, such as HAVAL, only provide multiple option for its output length. While the identity-based cryptosystem require that the length of the output can be any number. This study aims to create a hash function to fulfil the identity-based cryptosystem requirement. This study modifies the MD5 hashing algorithm to produce a variable length output, which called the Bit-Integer hash function. The result shows a proof-of-concept that Merkle-Damgård construction can be used to create a variable length hash function. The hash value of Bit-Integer hash function can produce random-like result which is essential for any cryptographic hash function.
A competing risks regression model based on the exponential Gompertz-like subdistribution
Authors: Kudus A , Suliadi S , Herlina M
Published: November 2019

In some situations, research activities are conducted to measure the length of time until the event occurred. If it is possible to have not only the event of interest but also the competing events, then it is a kind of competing risks data. The main parameter of interest is the subdistribution function that shows the percentage of failing individuals due to a cause of interest. If the subdistribution needs to be predicted by predictor variables, then the regression model for competing risks data should be developed. In this paper, the regression model for the exponential Gompertz-like subdistribution is proposed. We use maximum likelihood estimation method to estimate the model parameters. Specifically, the subdistribution of the main event and all the rest competing events are estimated simultaneously. The proposed model was applied to the data of contraceptive discontinuation and gave a good result. Goodness-of-fit of the estimated regression model measured by the likelihood and Akaike Information Criterion (AIC) also gave the acceptable values.
Context integration GIS of education relevant in secondary school TVET
Authors: Bakri A , Sugiarti Y , Wahyudin D
Published: November 2019

An initiative approach that focuses on software for the integration of GIS technology in the secondary school curriculum is the same, regardless of whether one teaches technical secondary school science, social secondary school, or basic art. While demonstration of sample resources and project approaches, technology-based education reforms, structured / standardized professional development workshops or courses, and teacher education programs that focus on technology are different because students need to learn GIS technology using learning materials tailored to their needs and situations. unique. The 'Learn about GIS' approach for TVET secondary school students is an effective way to operate software, with supporting instructions in cartography, database design, and programming. Learning to think of the world through the mediation perspective provided by technology can influence geospatial thinking and its development. The researcher notes that individual teacher support, local data usage, local problem scenarios, and administrative commitment, are critical issues for the development of professional GIS in TVET Middle School. Reforming the science and technology curriculum involving the acceptance of GIS in learning requires continuous professional development, related to the implementation of the GIS curriculum. Therefore, it is important to investigate the skills needed to improve the workability of TVET secondary schools in the Geomatics and Geospatial Engineering department.
Literature study on the theory of GIS-based multi evaluation criteria
Authors: Widianingsih I , Masri R M , Abdullah A G
Published: November 2019

Multi-criteria evaluation method is a method that can be used in making decisions by making complex issues into simple. GIS (Geographic Information System) is a tool that has a positive impact in the scientific decision-making process of planning for program development activities. Decision-making by integrating the multi-criteria evaluation with GIS has significant potential for the complexity of making a decision. The study of literature of this article focuses on the discussion of multi-criteria evaluation based on GIS. The purpose of writing this article is to organize and classify articles decisions using GIS-based MCDA. Based on the results of the study, determining the location of the housing using GIS-based multicriteria evaluation became the topic most widely presented. GIS-based multicriteria evaluation gave the result of decisions capable of precise, fast and effective.
Augmented reality based on stem for supporting science literacy in vocational education
Authors: Agustina W W , Sumarto S , Trisno B
Published: November 2019

AR development is becoming very popular in various fields of science. Some researchers have demonstrated that AR has the potential in science, technology, engineering, and mathematics (STEM). Puse of total AR integrated STEM needs to be studied more deeply, how STEM-AR characteristics, and how the potential of AR-based STEM to support the scientific literacy of students. Searches through relevant sources, the online database of which seven ACM Digital Library, ERIC, ieeexplore, ISI Web of Science, ScienceDirect, Scopus, and Springer. The results showed that the use of STEM-AR potentially an effort to improve science literacy.
The effectiveness of short message service advertising using EPIC model on consumer perception and purchase intention
Authors: Oktafani F , Suryawardani B
Published: November 2019

This study was aimed to find out the effectiveness of Telkomsel SMS advertising using EPIC Model, and to find out the influence of SMS advertising to perception and purchasing interest partially and simultaneously. The method used was descriptive verification with purposive sampling technique. Then the data was analyzed using path analysis. The results showed that the effectiveness of Telkomsel SMS advertising using EPIC model has 3.58 EPIC rate. Meanwhile, the influence of SMS advertising to customer perception was 40.6%, customer perception to purchasing interest was 25.6%, and SMS advertising to purchasing interest of Telkomsel sim card users was 19.4%.
Self-control and online game addiction in early adult gamers
Authors: Safarina N , Halimah L
Published: November 2019

Early adulthood is a productive period in development stage which involves more complex experiences and responsibilities. Contrary to what early adulthood should do, it was found that there were individuals who spent almost all their time playing online games at internet cafes. They always visit cyber cafes and usually play online games for at least 10 hours every day, which usually leads to various problem. This study aimed to see the correlation of self-control and online game addiction in early adult gamers. A total of 33 online gamers in early adulthood stage participated in this study and were asked to complete self-report measures using questionnaires. Questionnaires included demographic information, Brief Self-control Scale constructed by Tangney, et al. and Game Addiction Scale constructed by Lemmens, et al. Rank Spearman correlation was used to analyze the data and the result indicated that there are two aspects of self-control that have significant correlation with online game addiction (Deliberate/Non-impulsive and Self-discipline) and the other three aspects of self-control have insignificant correlation with online game addiction (Healthy Habit, Work Ethic, and Reliability). The overall result shows that self-control is significantly negative correlated with online game addiction. This means the lower the self-control, the more severe the probability of suffering online game addiction in early adult gamers.
20 years of INT KIT-USATU collaboration in the area of SPD
Authors: Hahn H , Ivanisenko Y , Kilmametov A
Published: November 2019

The field of Severe Plastic Deformation (SPD) has provided the scientific community with ultrafine grained and nanocrystalline materials. In contrast to other techniques for the synthesis of nanostructured materials, SPD processes allow the preparation of bulk quantities of metals and alloys. Technical applications have become a reality because commercial alloys can be transformed into novel nano- and microstructures, leading to superior mechanical properties, such as high strength and high ductility, resulting in many application areas. The field was pioneered at the Ufa State Aviation Technical University and has created worldwide interest. The report emphasizes some results of the close collaboration between Ufa State Aviation Technical University and the Institute of Nanotechnology at Karlsruhe Institute of Technology (KIT).
Strength and electroconductivity of bulk nanostructured copper alloys
Authors: Alexandrov I V , Wei W
Published: November 2019

The results of a study of the strength and conductivity of electrotechnical bulk nanostructured copper alloys obtained by methods of severe plastic deformation is presented. The contribution of the microstructure parameters to the formation of high strength while maintaining sufficient electrical conductivity is discussed.
Surface modification of CP-Ti metallic implant material by plasma electrolytic oxidation
Authors: Rameshbabu N , Ravisankar B , Saikiran A , Parfenov E V , Valiev R Z
Published: November 2019

Plasma electrolytic oxidation (PEO) is a relatively new and environmentally friendly process for development of thick and adherent oxide coatings on conventional and nanostructured metallic implant materials. The PEO process involves anodic oxidation of metals or alloys in aqueous solutions at voltages higher than the breakdown voltage of the oxides present on its surfaces. Currently, the PEO process is gaining increased attention as a novel technique for the fabrication of corrosion resistant, bioactive and functionally modulated composite coatings on commercial pure titanium (Cp-Ti) and Ti based alloys for orthopedic and dental applications. The PEO process coupled with the electrophoretic deposition (EPD) technique is used for the fabrication of TiO2/hydroxyapatite (HA) composite coating on a Cp-Ti implant material in a single step. This paper briefly reviews the properties of the coatings produced on Cp-Ti by PEO and PEO coupled EPD processes.
Deformation and current interaction in nanostructured and amorphous Ti based alloys
Authors: Stolyarov V V
Published: November 2019

The deformation behavior under tension and pulse current in course-grained, nanostructured and amorphous titanium based alloys is investigated. The influence of grain size, structure state and current mode on shape memory effect and electroplastic effect has been shown. Structure refinement up to nanosize area, occurrence of interphase boundaries, and amorphous state in alloys suppress the electroplastic effect. In TiNi alloys with phase thermoelastic transformation induced by deformation or temperature, current pulses decreases stress jumps downwards induced by manifestation of the electroplastic effect and increases stress jumps upwards connected with the shape memory effect.
Structural features and mechanical properties of Grade 4 titanium from VSMPO-AVISMA (Russia) and Grade 4 titanium from Carpenter Technology Corporation (USA), subjected to ECAP-Conform
Authors: Kodirov I S , Valiev R Z , Raab G I , Aleshin G N , Raab A G
Published: November 2019

In this paper, we analyze the microstructural features and mechanical properties of the Grade 4 titanium produced in Russia (VSMPO-AVISMA) and Grade 4 titanium from Carpenter Technology Corporation (USA). It is shown that during the ECAP-Conform processing and subsequent drawing, a homogeneous UFG structure is formed in both Ti materials, providing an enhanced level of mechanical properties with an ultimate tensile strength σB > 1200 MPa and an elongation to failure δ ~ 12%.
Plasma electrolytic polishing of nitrided steel under force convection condition
Authors: Belkin P N , Silkin S A , Dyakov I G , Tambovskiy I V , Korableva S S , Kusmanov S A
Published: November 2019

The effect of plasma electrolytic polishing in an ammonium chloride electrolyte under force convection condition on the characteristics of medium carbon steel after anodic plasma electrolytic nitriding was investigated. The morphology of the steel surface was studied using a metallographic microscope. The phase composition of the surface layers was studied using an X-ray diffractometer. Treatment specimens were tested under dry friction conditions with a counter body made of bearing steel. Corrosion studies were performed using potentiodynamic polarization curves in a 3.5 % sodium chloride solution. Nitriding increased the surface hardness up to 1130 HV due to the formation of a nitride-martensite layer with an outer oxide layer. After polishing of the nitrided surface, the loose outer part of the oxide layer containing microcracks and pores is removed, surface lightening has occurred. The reduction of the wear rate of 45-fold and the corrosion current density of 4.8-fold of nitrided steel by plasma polishing without changing the structure of the diffusion layers was shown.
Contribution of structural factors to the deformation behaviour of nanostructured Cu-Zn alloys
Authors: Chembarisova R G , Alexandrov I V , Zaynullina L I
Published: November 2019

The results of the analysis of the deformation behavior of nanostructured Cu-Zn alloys, obtained as a result of severe plastic deformation, implemented by the equal-channel angular pressing method, are presented. The role of structural factors responsible for increasing the strength characteristics and uniform elongation of the Cu-Zn alloys has been revealed.
Effects of grain refinement by HPT processing in carbon steel with various cementite morphology
Authors: Ganeev A V , Ivanisenko Y , Valiev R Z
Published: November 2019

This article reports on the effect of the initial phase composition (martensitic, patented, spheroidized) of the middle carbon steel C45 (0.45 wt.% C) on grain refinement during high-pressure torsion (HPT) at elevated temperature. It is established that the cementite dissolution and the final grain size after HPT strongly depend on the processing regime, as well as on the cementite morphology in the initial state of the steel. As result of this study, new approaches to obtain a very high-strength state in carbon steels have been proposed.
Effect of high-pressure torsion on the mechanical behavior of a Zr-based BMG
Authors: Gunderov D , Boltynjuk E , Churakova A , Batirshin E , Mullayanov A , Titov V , Ivanisenko J
Published: November 2019

The effect of high-pressure torsion (HPT) on the structure and mechanical properties of a Zr-based bulk metallic glass (BMG) was investigated. The structure of the BMG changes significantly after HPT processing. In tensile tests, the BMG samples before and after HPT processing are brittle under a stress of about 1700 MPa. For the first time, three-point bending tests of the HPT-processed BMG were performed. In the three-point bending tests of the initial BMG and that after HPT processing, the strength exceeds 3000 MPa and plastic flow is observed.
Combining methods of severe plastic deformation as an effective way to increase the strength of metallic materials
Authors: Ivanov A M
Published: November 2019

The article reviews the combined methods of severe plastic deformation (SPD) for hardening metallic materials. The combined deformation processing, extrusion with the equal-channel angular pressing (ECAP) is presented. The comparison is made of the mechanical characteristics and the fracture mode of the Fe360 low carbon steel strengthened by the combined methods of extrusion with ECAP and ECAP with extrusion.
Microstructure and mechanical properties of the Mg–Zn–Ca biodegradable alloy after severe plastic deformation
Authors: Khudododova G D , Kulyasova O B , Islamgaliev R K , Valiev R Z
Published: November 2019

Mg-Zn-Ca alloys are considered as promising biodegradable metals for implants because of their biocompatibility and proper physical properties. In this study, microstructure and strength of magnesium alloy Mg-1% Zn-0.2% Ca after a combination of the severe plastic deformation (SPD) methods have been investigated. It was shown that with an increase in the degree of deformation, an increase in the strength properties occurs. It was established that the ultimate tensile strength of the initial state was 125 MPa and after SPD a 2-fold increase in strength up to 283.3 MPa was achieved with sufficient ductility.
Relationship between the stress-strain state and the imperfection of the structure of metals with SPD shear
Authors: Raab G I , Raab A G , Aleshin G N , Kodirov I S
Published: November 2019

The paper presents the results of the computer simulation and physical experiment for the free and constrained transverse shear of round specimens of steel 10 with an accumulated strain of e> 1. The stress-strain state was investigated using computer simulation, and the degree of imperfection of the emerging structures was studied by metallographic methods. The laws governing the relationship between the parameters under study and the degree of imperfection of the structure during severe plastic deformation by shear are established.
Effect of point defects and functionalization on structural stability and electron properties of borophene as investigated by means of density functional theory
Authors: Khadiullin S Kh , Kistanov A A , Morkina A Y , Korznikova E A
Published: November 2019

The discovery of a new two dimensional material is a new trend emerged after the discovery of graphene in 2004. Hundreds of new materials have been predicted, designed and investigated during last decade. Many of them have outstanding properties for potential application in new technologies. One of those materials is so-called borophene, being isolated atomically thin boron. This material can show different electronic properties, including semiconducting, semi-metallic, and metallic states due to its unique structure. Borophene demonstrates unusually high in-plane elasticity and strength. The crucial point for application of borophene is its low structural stability at room temperature. A possible way to solve this problem is the functionalization of its surface by external atoms like hydrogen and fluorine. This work presents a study on the effect of O dopants and the presence of vacancy defects on electronic properties of borophene by using first-principles calculations. It was revealed that unlike other 2D materials, the band structure of borophene is stable by respect to the above-mentioned factors. However, the doping by O atoms is found as an effective way to increase the stability of the borophene sheet.
Evolution of the structure and mechanical properties of the Mg-1%Zn-0.2%Ca alloy during ECAP
Authors: Kulyasova O B , Evdokimova I A , Islamgaliev R K
Published: November 2019

Microstructure of the Mg-1%Zn-0.2%Ca magnesium alloy after equal-channel angular pressing (ECAP) has been investigated. It was shown that an increase of the shear strain leads to significant grain refinement, as well as to the improved uniformity of microhardness. As a result of grain refinement by ECAP processing, the microhardness was increased to a value of 45.5, which is 28% higher than the initial state. Tensile tests demonstrated the enhanced ultimate tensile strength of 248.1 MPa, yield stress of 153.2 MPa, ductility of 19.4 % whereas in the initial coarse-grained state these parameters were 124 MPa, 45.3 MPa and 8.7 %, accordingly.
Mechanical behavior of coarse- and fine-grained Al-6101 samples of different geometry under tension
Authors: Magomedova D K , Gunderov D V , Efimov M A
Published: November 2019

The paper presents the experimental data obtained during static tension of cylindrical samples of two structural states and two types of geometry from Al-6101 alloy at room temperature.