bluuebunny/crossref_metadata_2025 huggingface dataset:
Mycotic aneurysm of the hepatic artery in pediatric liver transplantation: A case series and literature review
Authors: Camagni S. , Stroppa P. , Tebaldi A. , Lucianetti A. , Pinelli D. , Pellicioli I. , D'Antiga L. , Colledan M.
Published: February 2018

Mycotic aneurysm of the hepatic artery (HA) is a rare, unpredictable, and potentially lethal complication of liver transplantation (LT). Pediatric LT is not exempt from it but the related literature is rather scanty. We present our experience with post‐LT mycotic aneurysm of the HA in pediatric age, describing four cases occurred with a special focus on the possible risk factors for its development and a proposal for the management of high‐risk recipients.
The biology of extracellular microvesicles
Authors: Sedgwick Alanna E. , D'Souza‐Schorey Crislyn
Published: February 2018

The study of extracellular vesicles (EVs) is a rapidly evolving field, owing in large part to recent advances in the realization of their significant contributions to normal physiology and disease. Once discredited as cell debris, these membrane vesicles have now emerged as mediators of intercellular communication by interaction with target cells, drug and gene delivery, and as potentially versatile platforms of clinical biomarkers as a result of their distinctive protein, nucleic acid and lipid cargoes. While there are multiple classes of EVs released from almost all cell types, here we focus primarily on the biogenesis, fate and functional cargoes of microvesicles (MVs). MVs regulate many important cellular processes including facilitating cell invasion, cell growth, evasion of immune response, stimulating angiogenesis, drug resistance and many others.
Jk3 alloantibodies during pregnancy—blood bank management and hemolytic disease of the fetus and newborn risk
Authors: Lawicki Shaun , Coberly Emily A. , Lee Laura A. , Johnson Mary , Eichbaum Quentin
Published: February 2018

BACKGROUND

The Kidd‐null phenotype, Jk(a−b−), occurs in individuals who do not express the JK glycoprotein. Jk(a−b−) individuals can make an antibody against the Jk3 antigen, a high‐incidence antigen present in more than 99.9% of most populations. This presents many challenges to the blood bank including identification of the antibody, masking of other antibodies, and how to provide transfusion support given the rarity of Jk3‐negative blood products. Kidd antibodies may cause acute and delayed hemolytic reactions as well as hemolytic disease of the fetus and newborn (HDFN). In this article, we present a series of four practical cases of pregnant women with the anti‐Jk3 alloantibody that demonstrate a range of clinical presentations of Kidd‐related HDFN.

STUDY DESIGN AND METHODS

We retrospectively reviewed the clinical and blood bank records for four patients and their newborns encountered at institutions in Tennessee, Missouri, Hawaii, and Guam with an anti‐Jk3 identified during pregnancy.

RESULTS

Two cases showed no significant evidence for HDFN, while two cases were of mild‐to‐moderate severity requiring early delivery due to elevated middle cerebral artery (MCA) flow velocities but requiring only phototherapy for hyperbilirubinemia. No intrauterine or neonatal transfusions were necessary. Anti‐Jk3 alloantibody titers ranged from 2 to 128.

CONCLUSION

Clinical manifestations of anti‐Jk3 HDFN are generally mild to moderate. Anti‐Jk3 titers were not found to correlate directly with HDFN severity. We suggest a titer of 16 to 32 as a cutoff for implementing enhanced monitoring of fetal MCA flow velocities, as such titers may be indicative of elevated HDFN risk.
Molecular basis of weak D expression in the Indian population and report of a novel, predominant variant RHD allele
Authors: Fichou Yann , Parchure Disha , Gogri Harita , Gopalkrishnan Vidya , Le Maréchal Cédric , Chen Jian‐Min , Férec Claude , Madkaikar Manisha , Ghosh Kanjaksha , Kulkarni Swati
Published: February 2018

BACKGROUND

The Rh blood group system is the most polymorphic system and is implicated in hemolytic transfusion reaction and hemolytic disease of the fetus and newborn. Molecular genetics of the RH genes have been extensively studied in Caucasians, Africans, and East Asians and the variant alleles giving rise to weak and partial D phenotypes have been reported. However, limited genetic studies have been carried out in the large Indian population, even though the variability of Rh expression has been documented.

STUDY DESIGN AND METHODS

In this study we sought to characterize the molecular bases of weak D expression in Indians. RHD gene in samples presenting with a weak D phenotype by serologic analyses (n = 223) was genotyped by conventional molecular approaches.

RESULTS

In addition to referenced and novel single‐nucleotide variations, a novel approximately 12‐kb duplication event, including Exon 3, was identified predominantly in variant D samples (130/223, 58.3%) and characterized at the nucleotide sequence level. Functional analyses suggested that this genetic variation quantitatively affects the expression of the normal transcript and then subsequently the expression of the normal RhD protein.

CONCLUSION

We describe a major novel, variant RHD allele in Indians that can be easily identified routinely by implementing a simple genotyping assay. Although we may consider this variation as a weak partial D variant, further studies and observations are needed to confirm the same. These findings may contribute to improve significantly Rh blood group diagnostics in more than one billion Indians.
Does being an IMF executive board member (Re)pay? An examination of IMF loans and repayments
Authors: Malan Franck A.
Published: February 2018

This paper analyses the political economy of IMF loans and repayments using data from 99 countries over the period 1984–2014. We bring two contributions to the literature, analysing: (i) the impact of the presence of a country on the IMF Executive Board and (ii) repayment behaviour (and not only loan requests). We show evidence that loans from, and repayments to, the IMF are influenced by the presence of countries on the IMF Executive Board. In particular, the results indicate that a position on the Board increases the loan amount by approximately 0.5 points and the repayment amount by approximately 0.2 points.
Amniotic membrane transplantation for ligneous conjunctivitis in a doberman
Authors: O'Leary Louise , Specht Andrew , Isaza Natalie , Kallberg Maria , Barrie Kathleen , Cottrell Deborah , Plummer Caryn
Published: February 2018

An approximately 2‐year‐old female Doberman Pinscher was referred for the evaluation of bilateral, chronic proliferative conjunctivitis. Ophthalmic examination revealed bilateral thick, opaque pseudomembranes originating from the conjunctivae that prevented visualization of the cornea and interior structures of the eye. Histopathological findings of biopsies of the pseudomembranes were consistent with ligneous conjunctivitis. Serum plasminogen activity levels were within the normal range. Treatment with topical and systemic anti‐inflammatory and immunosuppressive drugs did not improve the conjunctival lesions. The pseudomembranes were surgically excised, and the conjunctival surfaces were reconstructed with amniotic membrane. At final re‐examination two years postsurgery, there was no evidence of recurrence of the pseudomembranes. To the authors’ knowledge, this is the first reported case of the successful treatment of canine ligneous conjunctivitis with amniotic membrane transplantation.
An Empirical Study of Technological Innovations in the Field of Accounting - Boon or Bane
Authors: Khan Ahmad Khalid , Aboud Omar Abdullah Al , Faisal Syed Mohammad
Published: February 2018

In this paper researchers make an attempt by doing intense work that how technological innovations make jobs of accountant so easy from their routine jobs from posting to generating accounting statements etc. with the help of available software and technology in accounting field.Technological innovations have changed an obstructed job of accountant into easier one and that too rapid and accurate, with these developments researchers have found and witnessed that it has affected erstwhile as it has restricted entry for so many into an accounting field  as jobs of accountants have shrunk and in few hands who are technology accelerators and technology driven.Researchers have shown how technology has affected the outcome and impact on business in terms of accuracy, pace and swiftness.Researchers have made an attempt to explore various cause and effect relationship between available software in accounting, technology and accountants.In their intense and in depth research we have designed questionnaire comprised of many questions in which respondents are selected from top management, employees and included job seekers too in order to receive their unbiased responses during primary data collection.Wherever found necessary researchers have taken secondary data also to make study more accurate, interesting and feasible.
Analysis on the three-dimensional coupled vibration of composite cylindrical piezoelectric transducers
Authors: Xu Jie , Lin Shuyu
Published: February 2018

Three-dimensional coupled vibration of the composite cylindrical piezoelectric transducer is analyzed. The composite cylindrical piezoelectric transducer consists of an inner axially polarized piezoelectric ceramic cylinder and an outer metal cylinder with the same height. Coupled vibration of the composite cylindrical piezoelectric transducer is analyzed by equivalent elasticity method, which is an approximate analytical approach. According to this method, coupled vibration of the cylindrical transducer is regarded as an interaction between a plane radial vibration and a longitudinal vibration. The radial and longitudinal electromechanical equivalent circuits of the piezoelectric transducer are acquired. Input impedances as functions of the resonance frequency and the mechanical coupling coefficient are derived to obtain resonance frequency equations. The analytical results are supported by experimental and numerical simulated results of two prototypes of the piezoelectric transducer. The composite cylindrical piezoelectric transducer presented in this paper is superior to single cylindrical piezoelectric transducers, composite ring-type, and tube-type transducers in the field of high output power and efficiency.
Calcium-Dependent Protein Kinase 5 Is Required for Release of Egress-Specific Organelles in
Plasmodium falciparum
Authors: Absalon Sabrina , Blomqvist Karin , Rudlaff Rachel M. , DeLano Travis J. , Pollastri Michael P. , Dvorin Jeffrey D.
Published: February 2018

The human malaria parasite
Plasmodium falciparum
requires efficient egress out of an infected red blood cell for pathogenesis. This egress event is highly coordinated and is mediated by several signaling proteins, including the plant-like
P
.
falciparum
calcium-dependent protein kinase 5 (PfCDPK5). Knockdown of PfCDPK5 results in an egress block where parasites are trapped inside their host cells. The mechanism of this PfCDPK5-dependent block, however, remains unknown. Here, we show that PfCDPK5 colocalizes with a specialized set of parasite organelles known as micronemes and is required for their discharge, implicating failure of this step as the cause of the egress defect in PfCDPK5-deficient parasites. Furthermore, we show that PfCDPK5 cooperates with the
P
.
falciparum
cGMP-dependent kinase (PfPKG) to fully activate the protease cascade critical for parasite egress. The PfCDPK5-dependent arrest can be overcome by hyperactivation of PfPKG or by physical disruption of the arrested parasite, and we show that both treatments facilitate the release of the micronemes required for egress. Our results define the molecular mechanism of PfCDPK5 function and elucidate the complex signaling pathway of parasite egress.

IMPORTANCE
The signs and symptoms of clinical malaria result from the replication of parasites in human blood. Efficient egress of the malaria parasite
Plasmodium falciparum
out of an infected red blood cell is critical for pathogenesis. The
P
.
falciparum
calcium-dependent protein kinase 5 (PfCDPK5) is essential for parasite egress. Following PfCDPK5 knockdown, parasites remain trapped inside their host cell and do not egress, but the mechanism for this block remains unknown. We show that PfCDPK5 colocalizes with parasite organelles known as micronemes. We demonstrate that PfCDPK5 is critical for the discharge of these micronemes and that failure of this step is the molecular mechanism of the parasite egress arrest. We also show that hyperactivation of the cGMP-dependent kinase PKG can overcome this arrest. Our data suggest that small molecules that inhibit the egress signaling pathway could be effective antimalarial therapeutics.
Role of the Antigen Capture Pathway in the Induction of a Neutralizing Antibody Response to Anthrax Protective Antigen
Authors: Verma Anita , Ngundi Miriam M. , Price Gregory A. , Takeda Kazuyo , Yu James , Burns Drusilla L.
Published: February 2018

Toxin neutralizing antibodies represent the major mode of protective immunity against a number of toxin-mediated bacterial diseases, including anthrax; however, the cellular mechanisms that lead to optimal neutralizing antibody responses remain ill defined. Here we show that the cellular binding pathway of anthrax protective antigen (PA), the binding component of anthrax toxin, determines the toxin neutralizing antibody response to this antigen. PA, which binds cellular receptors and efficiently enters antigen-presenting cells by receptor-mediated endocytosis, was found to elicit robust anti-PA IgG and toxin neutralizing antibody responses. In contrast, a receptor binding-deficient mutant of PA, which does not bind receptors and only inefficiently enters antigen-presenting cells by macropinocytosis, elicited very poor antibody responses. A chimeric protein consisting of the receptor binding-deficient PA mutant tethered to the binding subunit of cholera toxin, which efficiently enters cells using the cholera toxin receptor rather than the PA receptor, elicited an anti-PA IgG antibody response similar to that elicited by wild-type PA; however, the chimeric protein elicited a poor toxin neutralizing antibody response. Taken together, our results demonstrate that the antigen capture pathway can dictate the magnitudes of the total IgG and toxin neutralizing antibody responses to PA as well as the ratio of the two responses.

IMPORTANCE
Neutralizing antibodies provide protection against a number of toxin-mediated bacterial diseases by inhibiting toxin action. Therefore, many bacterial vaccines are designed to induce a toxin neutralizing antibody response. We have used protective antigen (PA), the binding component of anthrax toxin, as a model antigen to investigate immune mechanisms important for the induction of robust toxin neutralizing antibody responses. We found that the pathway used by antigen-presenting cells to capture PA dictates the robustness of the neutralizing antibody response to this antigen. These results provide new insights into immune mechanisms that play an important role in the induction of toxin neutralizing antibody responses and may be useful in the design of new vaccines against toxin-mediated bacterial diseases.
Coiled-Coil Antagonism Regulates Activity of Venus Flytrap-Domain-Containing Sensor Kinases of the BvgS Family
Authors: Lesne Elodie , Dupré Elian , Lensink Marc F. , Locht Camille , Antoine Rudy , Jacob-Dubuisson Françoise
Published: February 2018

Bordetella pertussis
controls the expression of its virulence regulon through the two-component system BvgAS. BvgS is a prototype for a family of multidomain sensor kinases. In BvgS, helical linkers connect periplasmic Venus flytrap (VFT) perception domains to a cytoplasmic Per-Arnt-Sim (PAS) domain and the PAS domain to the dimerization/histidine phosphotransfer (DHp) domain of the kinase. The two linkers can adopt coiled-coil structures but cannot do so simultaneously. The first linker forms a coiled coil in the kinase mode and the second in the phosphatase mode, with the other linker in both cases showing an increase in dynamic behavior. The intervening PAS domain changes its quaternary structure between the two modes. In BvgS homologues without a PAS domain, a helical “X” linker directly connects the VFT and DHp domains. Here, we used BvgS as a platform to characterize regulation in members of the PAS-less subfamily. BvgS chimeras of homologues with natural X linkers displayed various regulation phenotypes. We identified two distinct coiled-coil registers in the N- and C-terminal portions of the X linkers. Stable coil formation in the C-terminal moiety determines the phosphatase mode, similarly to BvgS; in contrast, coil formation in the N-terminal moiety along the other register leads to the kinase mode. Thus, antagonism between two registers in the VFT-DHp linker forms the basis for activity regulation in the absence of the PAS domain. The N and C moieties of the X linker play roles similar to those played by the two independent linkers in sensor kinases with a PAS domain, providing a unified mechanism of regulation for the entire family.

IMPORTANCE
The whooping cough agent
Bordetella pertussis
uses the BvgAS sensory transduction two-component system to regulate production of its virulence factors. BvgS serves as a model for a large family of multidomain bacterial sensor kinases.
B. pertussis
is virulent when BvgS functions as a kinase and avirulent when it switches to phosphatase activity in response to modulating signals. Understanding the molecular regulation of those proteins might lead to new antibacterial strategies. Here, we show that the linker regions between the perception and the enzymatic domains shift between distinct states of conformation in an alternating manner in response to signals and that their antagonistic changes control sensor kinase activity. These linker regions and mechanistic principles appear to be conserved among BvgS homologues, irrespective of the presence or absence of an intervening domain between the perception and the enzymatic domains. This work has thus uncovered general molecular mechanisms that regulate activity of sensor kinases in the BvgS family.
Market Integration Predicts Human Gut Microbiome Attributes across a Gradient of Economic Development
Authors: Stagaman Keaton , Cepon-Robins Tara J. , Liebert Melissa A. , Gildner Theresa E. , Urlacher Samuel S. , Madimenos Felicia C. , Guillemin Karen , Snodgrass J. Josh , Sugiyama Lawrence S. , Bohannan Brendan J. M.
Published: February 2018

Previous research has reported differences in the gut microbiome between populations residing in wealthy versus poorer countries, leading to the assertion that lifestyle changes associated with economic development promote changes in the gut microbiome that promote the proliferation of microbiome-associated diseases. However, a direct relationship between economic development and the gut microbiome has not previously been shown. We surveyed the gut microbiomes of a single indigenous population undergoing economic development and found signiﬁcant associations between features of the gut microbiome and lifestyle changes associated with economic development. These ﬁndings suggest that even the earliest stages of economic development can drive changes in the gut microbiome, which may provide a warning sign for the development of microbiome-associated diseases.
Progressive idiopathic unilateral corneal endothelial failure of unknown aetiology in phakic eyes
Authors: Lee Weng Hon , Tey Adrian , Gales Kevin , Mudhar Hardeep Singh , Figueiredo Francisco C
Published: February 2018

Aim

To describe a cohort of patients with irreversible unilateral bullous keratopathy (BK) of undetermined aetiology.

Method

Retrospective, single-centre case series in a tertiary corneal referral centre.

Results

Eleven consecutive patients (nine females; mean age 71.7 years) presented from 1999 to 2009 with acute onset unilateral visual loss. At presentation, the best-corrected visual acuity of the affected eyes was 6/9 or worse with mean central corneal thickness (CCT) of 684 (SD 66) μm. Specular microscopy was not possible in the affected eyes. There was no other ocular pathology in the affected eye. The fellow eye remained normal throughout the study (mean endothelial cell density (ECD) of 1980 (SD 736) cells/mm2and CCT of 536 (SD 34) μm). Topical steroid, antiviral treatments (both topical and systemic) or a combination of both did not yield any improvement. After a mean follow-up of 82.2 months, eight eyes had penetrating keratoplasty (PK). One required two regrafts. Histology showed typical BK features, with endothelial cell (EC) loss and thickened Descemet’s membrane (DM). Transmission electron microscopy revealed DM abnormalities in a non-consistent pattern, featuring variable collagen deposition posterior to the non-banded zone. The ECs were degenerated, reduced or absent. Neither viruses nor pseudoexfoliation material was identified.

Conclusion

While medical treatment is not beneficial, PK appears to offer good results. Non-guttate Fuchs’ corneal endothelial dystrophy merits consideration but it would be unusual to see an exclusively unilateral presentation. DM thickening is reflective of a chronic EC loss but the cause of this loss remains elusive.
Single-cell RNAseq reveals seven classes of colonic sensory neuron
Authors: Hockley James R F , Taylor Toni S , Callejo Gerard , Wilbrey Anna L , Gutteridge Alex , Bach Karsten , Winchester Wendy J , Bulmer David C , McMurray Gordon , Smith Ewan St John
Published: February 2018

Objective

Integration of nutritional, microbial and inflammatory events along the gut-brain axis can alter bowel physiology and organism behaviour. Colonic sensory neurons activate reflex pathways and give rise to conscious sensation, but the diversity and division of function within these neurons is poorly understood. The identification of signalling pathways contributing to visceral sensation is constrained by a paucity of molecular markers. Here we address this by comprehensive transcriptomic profiling and unsupervised clustering of individual mouse colonic sensory neurons.

Design

Unbiased single-cell RNA-sequencing was performed on retrogradely traced mouse colonic sensory neurons isolated from both thoracolumbar (TL) and lumbosacral (LS) dorsal root ganglia associated with lumbar splanchnic and pelvic spinal pathways, respectively. Identified neuronal subtypes were validated by single-cell qRT-PCR, immunohistochemistry (IHC) and Ca2+-imaging.

Results

Transcriptomic profiling and unsupervised clustering of 314 colonic sensory neurons revealed seven neuronal subtypes. Of these, five neuronal subtypes accounted for 99% of TL neurons, with LS neurons almost exclusively populating the remaining two subtypes. We identify and classify neurons based on novel subtype-specific marker genes using single-cell qRT-PCR and IHC to validate subtypes derived from RNA-sequencing. Lastly, functional Ca2+-imaging was conducted on colonic sensory neurons to demonstrate subtype-selective differential agonist activation.

Conclusions

We identify seven subtypes of colonic sensory neurons using unbiased single-cell RNA-sequencing and confirm translation of patterning to protein expression, describing sensory diversity encompassing all modalities of colonic neuronal sensitivity. These results provide a pathway to molecular interrogation of colonic sensory innervation in health and disease, together with identifying novel targets for drug development.
Penetrance estimates for BRCA1, BRCA2 (also applied to Lynch syndrome) based on presymptomatic testing: a new unbiased method to assess risk?
Authors: Evans D Gareth , Woodward Emma , Harkness Elaine F , Howell Anthony , Plaskocinska Inga , Maher Eamonn R , Tischkowitz Marc D , Lalloo Fiona
Published: February 2018

Purpose

The identification of BRCA1, BRCA2 or mismatch repair (MMR) pathogenic gene variants in familial breast/ovarian/colorectal cancer families facilitates predictive genetic testing of at-risk relatives. However, controversy still exists regarding overall lifetime risks of cancer in individuals testing positive.

Methods

We assessed the penetrance of BRCA1, BRCA2, MLH1 and MSH2 mutations in men and women using Bayesian calculations based on ratios of positive to negative presymptomatic testing by 10-year age cohorts. Mutation position was also assessed for BRCA1/BRCA2.

Results

Using results from 2264 presymptomatic tests in first-degree relatives (FDRs) of mutation carriers in BRCA1 and BRCA2 and 646 FDRs of patients with MMR mutations, we assessed overall associated cancer penetrance to age of 68 years as 73% (95% CI 61% to 82%) for BRCA1, 60% (95% CI 49% to 71%) for BRCA2, 95% (95% CI 76% to 99%) for MLH1% and 61% (95% CI 49% to 76%) for MSH2. There was no evidence for significant penetrance for males in BRCA1 or BRCA2 families and males had equivalent penetrance to females with Lynch syndrome. Mutation position and degree of family history influenced penetrance in BRCA2 but not BRCA1.

Conclusion

We describe a new method for assessing penetrance in cancer-prone syndromes. Results are in keeping with published prospective series and present modern-day estimates for overall disease penetrance that bypasses retrospective series biases.
Differences in the motor unit firing rates and amplitudes in relation to recruitment thresholds during submaximal contractions of the first dorsal interosseous between chronically resistance-trained and physically active men
Authors: Sterczala Adam J. , Miller Jonathan D. , Trevino Michael A. , Dimmick Hannah L. , Herda Trent J.
Published: February 2018

Previous investigations report no changes in motor unit (MU) firing rates during submaximal contractions following resistance training. These investigations did not account for MU recruitment or examine firing rates as a function of recruitment threshold (REC). Therefore, MU recruitment and firing rates in chronically resistance-trained (RT) and physically active controls (CON) were examined. Surface electromyography signals were collected from the first dorsal interosseous during isometric muscle actions at 40% and 70% maximal voluntary contraction (MVC). For each MU, force at REC, mean firing rate (MFR) during the steady force, and MU action potential amplitude (MUAPAMP) were analyzed. For each individual and contraction, the MFRs were linearly regressed against REC, whereas, exponential models were applied to the MFR versus MUAPAMP and MUAPAMP versus REC relationships with the y-intercepts and slopes (linear) and A and B terms (exponential) calculated. For the 40% MVC, the RT had less negative slopes (p = 0.001) and lower y-intercepts (p = 0.006) of the MFR versus REC relationships and lower B terms (p = 0.011) of the MUAPAMP versus REC relationships. There were no differences in either relationship between groups for the 70% MVC. During the 40% MVC, the RT had a smaller range of MFRs and MUAPAMPS in comparison with the CON, likely because of reduced MU recruitment. The RT had lower MFRs and recruitment during the 40% MVC, which may indicate a leftward shift in the force–frequency relationship, and thus require less excitation to the motoneuron pool to match the same relative force.
Effect of intermediate fluid layer on Kelvin–Helmholtz instability
Authors: Zhang Ying , Shang Wenqiang , Yao Mengjun , Dong Boheng , Li Peisheng
Published: February 2018

Two-dimensional K-H (Kelvin–Helmholtz) instability of the three-component immiscible fluids with an intermediate fluid layer is numerically studied using the front-tracking method (FTM). The instability is governed by the Navier–Stokes equations and the conservation of mass equation for incompressible flow. A finite difference method is used to discretize the governing system. This study focuses on the influence of flow configuration, the thickness of intermediate fluid layer and the distribution of intermediate fluid layer on K-H instability. It is shown that the larger the initial horizontal velocity difference is, the faster the internal disturbance increases, and the characteristic form of K-H instability becomes more obvious for different flow configuration. It is also observed that the thickness of the intermediate fluid layer is negatively correlated to the billow height and the numerical growth rate. In addition, when the intermediate fluid layer is thicker than 0.4 times the disturbance wavelength, the billow height and the numerical growth rate for the K-H instability of the upper and lower interfaces change over time synchronously. The higher the initial height of the lower interface is, the greater the growth rate and billow height of the upper interface are. Besides, the upper and lower interfaces are rolled up synchronously over time when the intermediate fluid layer is symmetrically distributed with y = 0.5 in the fluid system.
Spinor field in Bianchi type-IX space–time
Authors: Saha Bijan
Published: February 2018

Within the scope of Bianchi type-IX cosmological model we have studied the role of spinor field in the evolution of the Universe. It is found that unlike the diagonal Bianchi models in this case the components of energy–momentum tensor of spinor field along the principal axis are not the same (i.e., [Formula: see text]), even in the absence of spinor field nonlinearity. The presence of nontrivial non-diagonal components of energy–momentum tensor of the spinor field imposes severe restrictions both on geometry of space–time and on the spinor field itself. As a result the space–time turns out to be either locally rotationally symmetric or isotropic. In this paper we considered the Bianchi type-IX space–time both for a trivial b, that corresponds to standard Bianchi type-IX and the one with a non-trivial b. It was found that a positive self-coupling constant λ1 gives rise to an oscillatory mode of expansion, while a trivial λ1 leads to rapid expansion at the early stage of evolution.
Allowed and forbidden transition rates and corresponding wavelengths for Si-like Au ion (Au65+) by relativistic configuration interaction method
Authors: Hamasha S.M. , Almashaqba A.
Published: February 2018

Large-scale atomic calculations are carried out to produce data of atomic structure and transitions rates for Si-like Au ion (Au65+). Generated atomic data are essential for modeling of M-shell spectra of gold ions in Au plasma, and fusion research. Energy levels are calculated by applying two methods: the relativistic configuration interaction method (RCI) of the flexible atomic code (FAC) and the multi-reference many body perturbation theory method (MR-MBPT). Energy levels, oscillator strengths, and transition rates are calculated for transitions between excited and ground states from n = 3l to n′l′, where n′ = 4, 5, 6, and 7; and l and l′ are the proper angular momenta of shells n and n′, respectively. The electric dipole (E1), electric quadrupole (E2), electric octupole (E3), magnetic dipole (M1), magnetic quadrupole (M2), and magnetic octupole (M3) transitions are all considered in the calculations. Correlation effects, relativistic effects, and QED effects are also included in the calculations. The two methods yield comparable values of energy levels. Data of energy levels of low-lying states and data for inner shell transitions reported in this study demonstrate good agreement with published experimental and theoretical data.
Einstein’s accelerated reference systems and Fermi–Walker coordinates
Authors: Llosa Josep
Published: February 2018

We show that the uniformly accelerated reference systems proposed by Einstein when introducing acceleration in the theory of relativity are what is known at present as Fermi–Walker coordinate systems. We then consider more general accelerated motions and, on the one hand we obtain Thomas precession and, on the other, we prove that the only accelerated reference systems that at any time admit an instantaneously comoving inertial system belong necessarily to the Fermi–Walker class.
Emptiness of Ordered Multi-Pushdown Automata is 2ETIME-Complete
Authors: Atig Mohamed Faouzi , Bollig Benedikt , Habermehl Peter
Published: February 2018

We consider ordered multi-pushdown automata, a multi-stack extension of pushdown automata that comes with a constraint on stack operations: a pop can only be performed on the first non-empty stack (which implies that we assume a linear ordering on the collection of stacks). We show that the emptiness problem for multi-pushdown automata is 2ETIME-complete. Containment in 2ETIME is shown by translating an automaton into a grammar for which we can check if the generated language is empty. The lower bound is established by simulating the behavior of an alternating Turing machine working in exponential space. We also compare ordered multi-pushdown automata with the model of bounded-phase (visibly) multi-stack pushdown automata, which do not impose an ordering on stacks, but restrict the number of alternations of pop operations on different stacks.
A Self-Stabilizing Algorithm for a Maximal 2-Packing in a Cactus Graph Under Any Scheduler
Authors: Trejo-Sánchez Joel Antonio , Fernández-Zepeda José Alberto , Ramírez-Pacheco Julio César
Published: February 2018

In this paper, we present a self-stabilizing algorithm that computes a maximal 2-packing set in a cactus under the adversarial scheduler. The cactus is a network topology such that any edge belongs to at most one cycle. The cactus has important applications in telecommunication networks, location problems, and biotechnology, among others. We assume that the value of each vertex identifier can take any value of length [Formula: see text] bits. The execution time of this algorithm is [Formula: see text] rounds or [Formula: see text] time steps. Our algorithm matches the state of the art results for this problem, following an entirely different approach. Our approach allows the computation of the maximum 2-packing when the cactus is a ring.
Ab-initio thermodynamic and elastic properties of AlNi and AlNi3intermetallic compounds
Authors: Yalameha Shahram , Vaez Aminollah
Published: February 2018

In this paper, thermodynamic and elastic properties of the AlNi and AlNi3were investigated using density functional theory (DFT). The full-potential linearized augmented plane-wave (APW) in the framework of the generalized gradient approximation as used as implemented in the Wien2k package. The temperature dependence of thermal expansion coefficient, bulk modulus and heat capacity in a wide range of temperature (0–1600 K) were investigated. The calculated elastic properties of the compounds show that both intermetallic compounds of AlNi and AlNi3have surprisingly negative Poisson’s ratio (NPR). The results were compared with other experimental and computational data.
On resolvability of a graph associated to a finite vector space
Authors: Ali U. , Bokhary S. A. , Wahid K. , Abbas G.
Published: February 2018

In this paper, the resolving parameters such as metric dimension and partition dimension for the nonzero component graph, associated to a finite vector space, are discussed. The exact values of these parameters are determined. It is derived that the notions of metric dimension and locating-domination number coincide in the graph. Independent sets, introduced by Boutin [Determining sets, resolving set, and the exchange property, Graphs Combin. 25 (2009) 789–806], are studied in the graph. It is shown that the exchange property holds in the graph for minimal resolving sets with some exceptions. Consequently, a minimal resolving set of the graph is a basis for a matroid with the set [Formula: see text] of nonzero vectors of the vector space as the ground set. The matroid intersection problem for two matroids with [Formula: see text] as the ground set is also solved.
MSSM inflation and cosmological attractors
Authors: Dubinin M. N. , Petrova E. Yu. , Pozdeeva E. O. , Vernov S. Yu.
Published: February 2018

Inflationary scenarios motivated by the minimal supersymmetric standard model (MSSM) where five scalar fields are non-minimally coupled to gravity are considered. The potential of the model and the function of non-minimal coupling are polynomials of two Higgs doublet convolutions. We show that the use of the strong coupling approximation allows to obtain inflationary parameters in the case when a combination of the four scalar fields plays a role of inflaton. Numerical calculations show that the cosmological evolution leads to inflationary scenarios fully compatible with observational data for different values of the MSSM mixing angle [Formula: see text].
When the maximal graph is planar, outerplanar, and ring graph
Authors: Sharma Arti , Gaur Atul
Published: February 2018

Let [Formula: see text] be a commutative ring with nonzero identity. Let [Formula: see text] denote the maximal graph associated to [Formula: see text], that is, [Formula: see text] is a graph with vertices as non-units of [Formula: see text], where two distinct vertices [Formula: see text] and [Formula: see text] are adjacent if and only if there is a maximal ideal of [Formula: see text] containing both. In this paper, we characterize the finite commutative rings such that their maximal graph are planar graphs, and we also study the case where they are outerplanar and ring graphs. The equivalence of outerplanar graphs and ring graphs for [Formula: see text] is established.
clfB-tree
Authors: Kim Wook-Hee , Seo Jihye , Kim Jinwoong , Nam Beomseok
Published: February 2018

Emerging byte-addressable non-volatile memory (NVRAM) is expected to replace block device storages as an alternative low-latency persistent storage device. If NVRAM is used as a persistent storage device, a cache line instead of a disk page will be the unit of data transfer, consistency, and durability.

In this work, we design and develop
clfB-tree
—a B-tree structure whose tree node fits in a single cache line. We employ existing
write combining store buffer
and
restricted transactional memory
to provide a
failure-atomic cache line write
operation. Using the failure-atomic cache line write operations, we atomically update a clfB-tree node via a single cache line flush instruction without major changes in hardware. However, there exist many processors that do not provide SW interface for transactional memory. For those processors, our proposed clfB-tree achieves atomicity and consistency via in-place update, which requires maximum four cache line flushes. We evaluate the performance of clfB-tree on an NVRAM emulation board with ARM Cortex A-9 processor and a workstation that has Intel Xeon E7-4809 v3 processor. Our experimental results show clfB-tree outperforms wB-tree and CDDS B-tree by a large margin in terms of both insertion and search performance.
Persisting RB-Tree into NVM in a Consistency Perspective
Authors: Wang Chundong , Wei Qingsong , Wu Lingkun , Wang Sibo , Chen Cheng , Xiao Xiaokui , Yang Jun , Xue Mingdi , Yang Yechao
Published: February 2018

Byte-addressable non-volatile memory (NVM) is going to reshape conventional computer systems. With advantages of low latency, byte-addressability, and non-volatility, NVM can be directly put on the memory bus to replace DRAM. As a result, both system and application softwares have to be adjusted to perceive the fact that the persistent layer moves up to the memory. However, most of the current in-memory data structures will be problematic with consistency issues if not well tuned with NVM. This article places emphasis on an important in-memory structure that is widely used in computer systems, i.e., the Red/Black-tree (RB-tree). Since it has a long and complicated update process, the RB-tree is prone to inconsistency problems with NVM. This article presents an NVM-compatible consistent RB-tree with a new technique named
cascade-versioning
. The proposed RB-tree (i) is all-time consistent and scalable and (ii) needs no recovery procedure after system crashes. Experiment results show that the RB-tree for NVM not only achieves the aim of consistency with insignificant spatial overhead but also yields comparable performance to an ordinary volatile RB-tree.
UnistorFS
Authors: Chen Shuo-Han , Chen Tseng-Yi , Chang Yuan-Hao , Wei Hsin-Wen , Shih Wei-Kuan
Published: February 2018

With the advanced technology in persistent random access memory (PRAM), PRAM such as three-dimen-sional XPoint memory and Phase Change Memory (PCM) is emerging as a promising candidate for the next-generation medium for both (main) memory and storage. Previous works mainly focus on how to overcome the possible endurance issues of PRAM while both main memory and storage own a partition on the same PRAM device. However, a holistic software-level system design should be proposed to fully exploit the benefit of PRAM. This article proposes a union storage file system (UnistorFS), which aims to jointly manage the PRAM resource for main memory and storage. The proposed UnistorFS realizes the concept of using the PRAM resource as memory and storage interchangeably to achieve resource sharing while main memory and storage coexist on the same PRAM device with no partition or logical boundary. This approach not only enables PRAM resource sharing but also eliminates unnecessary data movements between main memory and storage since they are already in the same address space and can be accessed directly. At the same time, the proposed UnistorFS ensures the persistence of file data and sanity of the file system after power recycling. A series of experiments was conducted on a modified Linux kernel. The results show that the proposed UnistorFS can eliminate unnecessary memory accesses and outperform other PRAM-based file systems for 0.2--8.7 times in terms of read/write performance.
A k-Deviation Density Based Clustering Algorithm
Authors: Jungan Chen , Jinyin Chen , Dongyong Yang , Jun Li
Published: February 2018

Due to the adoption of global parameters, DBSCAN fails to identify clusters with different and varied densities. To solve the problem, this paper extends DBSCAN by exploiting a new density definition and proposes a novel algorithm called k-deviation density based DBSCAN (kDDBSCAN). Various datasets containing clusters with arbitrary shapes and different or varied densities are used to demonstrate the performance and investigate the feasibility and practicality of kDDBSCAN. The results show that kDDBSCAN performs better than DBSCAN.
Simulating the Evolution of Fluid Underpressures in the Great Plains, by Incorporation of Tectonic Uplift and Tilting, with a Groundwater Flow Model
Authors: Umari Amjad M. J. , Nelson Philip H. , Fridrich Chris , LeCain Gary D.
Published: February 2018

Underpressures (subhydrostatic heads) in the Paleozoic units underlying the Great Plains of North America are a consequence of Cenozoic uplift of the area. Based on tectonostratigraphic data, we have developed a cumulative uplift history with superimposed periods of deposition and erosion for the Great Plains for the period from 40 Ma to the present. Uplift, deposition, and erosion on an 800 km geologic cross-section extending from northeast Colorado to eastern Kansas is represented in nine time-stepped geohydrologic models. Sequential solution of the two-dimensional diffusion equation reveals the evolution of hydraulic head and underpressure in a changing structural environment after 40 Ma, culminating in an approximate match with the measured present-day values. The modeled and measured hydraulic head values indicate that underpressures increase to the west. The 2 to 0 Ma model indicates that the present-day hydraulic head values of the Paleozoic units have not reached steady state. This result is significant because it indicates that present-day hydraulic heads are not at equilibrium, and underpressures will increase in the future. The pattern uncovered by the series of nine MODFLOW models is of increased underpressures with time. Overall, the models indicate that tectonic uplift explains the development of underpressures in the Great Plains.
Finite-Time Robust H∞ Control for Uncertain Linear Continuous-Time Singular Systems with Exogenous Disturbances
Authors: Wo Songlin , Li Bo
Published: February 2018

Singular systems arise in a great deal of domains of engineering and can be used to solve problems which are more difficult and more extensive than regular systems to solve. Therefore, in this paper, the definition of finite-time robust H∞ control for uncertain linear continuous-time singular systems is presented. The problem we address is to design a robust state feedback controller which can deal with the singular system with time-varying norm-bounded exogenous disturbance, such that the singular system is finite-time robust bounded (FTRB) with disturbance attenuation γ. Sufficient conditions for the existence of solutions to this problem are obtained in terms of linear matrix equalities (LMIs). When these LMIs are feasible, the desired robust controller is given. A detailed solving method is proposed for the restricted linear matrix inequalities. Finally, examples are given to show the validity of the methodology.
Physiochemical Restrictions of Mineral Zoning of Sediment-Hosted Stratiform Copper Deposit in SW China
Authors: Zhang Yan , Han Runsheng , Wen Shuming , Wei Pingtang
Published: February 2018

The Chuxiong basin, located in southwest China, is well known as a mineralization area of red-bed type copper deposits in China. These deposits are characterized by mineral zoning, which is especially true for the Dayao deposits. The mineral zoning is consistent for both horizontal and vertical zoning; from the base (center) of the ore body to the top (outermost), the mineral zones are from hematite, chalcocite, chalcocite + bornite, and bornite + chalcopyrite to pyrite. We studied the mineral zoning in detail using a thermodynamic phase diagram method, such as log⁡fO2-log⁡fS2, pH-log⁡fO2, and pH-Eh, and discussed the constraints on the order of the minerals precipitation under different physiochemical conditions. It is indicated that changes in temperature have little effect on pH and Eh in the formation of minerals. S2− is stable only below 473 K, and the forming temperature of chalcocite must be below 473 K. In this paper, we also explain the mineral zoning formation mechanism and propose that the main controlling factor of mineral zoning is pH. Because this mineral zoning is widespread in sediment-hosted deposits, studies on this mechanism can considerably promote better understanding of the genesis of ore deposits in order to guide the exploration.
Corneal Subbasal Nerve Recovery in an Acute Case of Ultraviolet Keratitis Treated with Autologous Serum Eye Drops
Authors: Abedi Farshad , Hamrah Pedram
Published: February 2018

Purpose. To report degeneration of subbasal corneal nerves and the subsequent neuroregeneration in a case of acute ultraviolet (UV) keratitis, treated with autologous serum eye drops. Methods. Case report. Results. A 37-year-old female presented with ocular discomfort and blurred vision in both eyes, after exposure to UV-C light in a laboratory. On exam, she had bilateral conjunctival injection and superficial punctate keratitis (SPK), worse in the left, consistent with acute, bilateral, but asymmetric UV-C keratitis. She was initially started on antibiotic ointment and lubricant eye drops. On her follow-up visit 3 days later, corneas had persistent SPK bilaterally. Laser scanning in vivo confocal microscopy (IVCM) showed beading of subbasal corneal nerves in the right eye and decreased subbasal corneal nerve density and numerous amputated nerves in the left eye. Autologous serum eye drops 20%, eight times a day, and loteprednol 0.5% ophthalmic solution were commenced in both eyes. Twelve weeks later, her symptoms fully resolved; IVCM revealed near-normal subbasal corneal nerve density in both eyes. Conclusions. IVCM demonstrated dramatic damage to subbasal corneal nerves after brief UV-C exposure. The patient, treated with autologous serum eye drops in both eyes, achieved resolution of symptoms and recovery of subbasal corneal nerves.