bluuebunny/crossref_metadata_2025_split huggingface dataset:
Linear Quaternion Differential Equations: Basic Theory and Fundamental Results
Authors: Kou Kit Ian , Xia Yong‐Hui 
Published: April 2018

AbstractQuaternion‐valued differential equations (QDEs) are a new kind of differential equations which have many applications in physics and life sciences. The largest difference between QDEs and ordinary differential equations (ODEs) is the algebraic structure. Due to the noncommutativity of the quaternion algebra, the set of all the solutions to the linear homogenous QDEs is completely different from ODEs. It is actually a right‐free module, not a linear vector space.This paper establishes a systematic frame work for the theory of linear QDEs, which can be applied to quantum mechanics, fluid mechanics, Frenet frame in differential geometry, kinematic modeling, attitude dynamics, Kalman filter design, spatial rigid body dynamics, etc. We prove that the set of all the solutions to the linear homogenous QDEs is actually a right‐free module, not a linear vector space. On the noncommutativity of the quaternion algebra, many concepts and properties for the ODEs cannot be used. They should be redefined accordingly. A definition of Wronskian is introduced under the framework of quaternions which is different from standard one in the ODEs. Liouville formula for QDEs is given. Also, it is necessary to treat the eigenvalue problems with left and right sides, accordingly. Upon these, we studied the solutions to the linear QDEs. Furthermore, we present two algorithms to evaluate the fundamental matrix. Some concrete examples are given to show the feasibility of the obtained algorithms. Finally, a conclusion and discussion ends the paper.
Numerical Study of Blow‐Up Mechanisms for Davey–Stewartson II Systems
Authors: Klein Christian , Stoilov Nikola 
Published: April 2018

AbstractWe present a detailed numerical study of various blow‐up issues in the context of the focusing Davey–Stewartson II equation. To this end, we study Gaussian initial data and perturbations of the lump and the explicit blow‐up solution due to Ozawa. Based on the numerical results it is conjectured that the blow‐up in all cases is self‐similar, and that the time‐dependent scaling behaves as in the Ozawa solution and not as in the stable blow‐up of standard L2 critical nonlinear Schrödinger equation. The blow‐up profile is given by a dynamically rescaled lump.
Preparation and characterization of PTFE flat sheet membrane: Effect of sodium benzoate content
Authors: Abd Ghani Faezeah , Hamzah Khaidir , Wan Salleh Wan Norharyati , Mohamed Hasimah 
Published: April 2018

Polytetrafluoroethylene (PTFE) flat sheet membranes were prepared through casting and sintering methods. The effect of sodium benzoate salt on the characteristics of PTFE flat sheet membranes such as morphology, surface roughness, porosity, mechanical strength and crystallinity were studied through scanning electron microscopy (SEM), atomic force microscopy (AFM), mercury intrusion porosimetry, tensile test and X-ray diffraction (XRD). SEM analysis confirmed the formation of irregular porous microstructures in sponge-like configuration. All the fabricated membranes exhibited narrow pore size distributions and have relatively small average pore diameters between 0.074 and 1.068 µm despite having porosity between 36.41 and 74.32 %. In addition, the roughness of the PTFE flat sheet membranes increased as the sodium benzoate content increased. Increasing sodium benzoate content was positive for pore size, porosity and roughness but negative for surface roughness and mechanical properties. This research confirmed that the addition of sodium benzoate salt in aqueous PTFE solution is a useful approach for the fabrication of porous PTFE flat sheet membranes
The effect of mass ratio on the flow characteristics of hydrogen-natural gas mixture using reduced order modelling
Authors: Subani Norazlina , Amin Norsarahaida 
Published: April 2018

This work focuses on the development of a mathematical model as a viable alternative to pinpoint locations of gas leaks in a pipeline. The transient non-isothermal flow of hydrogen-natural gas mixture is considered because hydrogen is often transported in the same pipeline as natural gas to reduce the transportation cost. The mathematical model developed took into consideration the effect of the mass ratio of gas mixture. The gas mixture was assumed to be homogeneous and the transient pressure wave was created by the sudden or instantaneous closure of a downstream shut-off valve to ensure the attainment of minimum pressure at the downstream end within a short time. The governing equations were numerically solved using the reduced order modelling (ROM) technique, which had not been previously applied on non-isothermal models involving gas mixtures. Numerical results observed that the mass ratio of hydrogen to natural gas should not be more than 0.5 to ensure that leakage does not occur before the estimated leak position. An increase in the mass ratio leads to an increase in the pressure and celerity wave, while the leak location and the amount of leak discharge decrease.
Convergence of modified homotopy perturbation method for Fredholm-Volterra integro-differential equation of order m
Authors: K. Eshkuvatov Zainidin , Zulkarnain Fatimah Samihah , Muminov Zahriddin , Nik Long Nik Mohd Asri 
Published: April 2018

In this paper, modified homotopy perturbation method (MHPM) is applied to solve the general Fredholm-Volterra integro-differential equations (FV-IDEs) of order with initial conditions. Selective functions and unknown parameters allowed us to obtain two step iterations. It is found that MHPM is a semi-analytical method for FV-IDEs and could avoid complex computations. Numerical examples are given to show the efficiency and reliability of the method. Proof of the convergence of the proposed method is also given.
Management of dexamethasone-induced hyperglycemia in patients undergoing chemotherapy in an outpatient setting: a best practice implementation project
Authors: Sinaga Gery , de Koeijer Elizabeth 
Published: April 2018

ABSTRACT

Objectives:
The objective of this project was to implement best practice in an outpatient clinical setting in order to increase both nursing staff and patients’ knowledge and awareness on the importance of blood sugar management during chemotherapy and to show that through compliance with best practice, the incidence of dexamethasone-induced hyperglycemia during chemotherapy can be minimized.

Introduction:
Steroid-induced hyperglycemia is a commonly neglected symptom in cancer treatment, contributing to poor patient prognosis and extended hospital stay. Evidence shows that controlled blood sugar during chemotherapy is associated with improved patient outcomes and better tolerance to cancer treatment. For the purpose of this paper steroid-induced hyperglycemia will be referred to as dexamethasone-induced hyperglycemia.

Methods:
This project utilized the Joanna Briggs Institute Practical Application of Clinical Evidence System (JBI-PACES) and Getting Research into Practice (GRiP) audit tools to promote compliance in the clinical setting. Thirty patients participated in the audit, which was executed by nursing staff in the Medical Oncology Outpatient Unit at the Cancer Ambulatory and Community Health Support Department at the Canberra Hospital.

Results:
The baseline audit revealed large gaps between best practice and current practice. This underlined the need for more education for both nursing staff and patients. Other barriers such as the absence of assessment and documentation by the clinicians and the minimum number of potential referrals to the diabetes educator were addressed by encouraging patients to speak about their diabetes, and also in the development of a simplified referral process in order to have patients reviewed by the Diabetes Educator in a timely manner. There were significant improvements after more information sessions were held and more resources made available to both nursing staff and patients, but there were also minimal to zero compliance drop on parts of the follow-up audit.

Conclusions:
In an attempt to improve patient outcome during chemotherapy, the project has succeeded in changing the attitude towards blood sugar control, and in increasing knowledge and awareness of dexamethasone-induced hyperglycemia among nursing staff and patients. However, there is room for improvement, based on the results of the implementation project. Future audits are planned to ensure sustainability.
Defining Substrate Specificity in the CTX-M Family: the Role of Asp240 in Ceftazidime Hydrolysis
Authors: Ghiglione Barbara , Rodríguez María Margarita , Curto Lucrecia , Brunetti Florencia , Dropa Milena , Bonomo Robert A. , Power Pablo , Gutkind Gabriel 
Published: April 2018

ABSTRACT

The natural diversification of CTX-M β-lactamases led to the emergence of Asp240Gly variants in the clinic that confer reduced susceptibility to ceftazidime (CAZ). In this study, we compared the impact of this substitution on CAZ and ceftazidime-avibactam (CZA) MICs against isogenic
Escherichia coli
strains with different porin deficiencies. Our results show a noticeable increase in CAZ resistance in clones expressing Asp240Gly-harboring CTX-M when combined with OmpF porin deficiency. Kinetic analysis revealed that the
k
cat
/

K
m

for CAZ was 5- to 15-fold higher for all Asp240Gly variants but remained 200- to 725-fold lower than that for cefotaxime (CTX).
In vitro
selection of CAZ-resistant clones yielded nonsusceptible CTX-M producers (MIC of >16 μg/ml) only after overnight incubation; the addition of avibactam (AVI) decreased MICs to a susceptible range against these variants. In contrast, the use of CZA as a selective agent did not yield resistant clones. AVI inactivated both CTX-M-12 and CTX-M-96, with an apparent inhibition constant comparable to that of SHV-2 and 1,000-fold greater than that of PER-2 and CMY-2, and

k
2
/K

for CTX-M-12 was 24- and 35-fold higher than that for CTX-M-96 and CTX-M-15, respectively. Molecular modeling suggests that AVI interacts similarly with CTX-M-96 and CTX-M-15. We conclude that the impact of Asp240Gly in resistance may arise when other mechanisms are also present (i.e., OmpF deficiency). Additionally, CAZ selection could favor the emergence of CAZ-resistant subpopulations. These results define the role of Asp240 and the impact of the -Gly substitution and allow us to hypothesize that the use of CZA is an effective preventive strategy to delay the development of resistance in this family of extended-spectrum β-lactamases.
Important Late-Stage Symbiotic Role of the Sinorhizobium meliloti Exopolysaccharide Succinoglycan
Authors: Arnold Markus F. F. , Penterman Jon , Shabab Mohammed , Chen Esther J. , Walker Graham C. 
Published: April 2018

ABSTRACT

Sinorhizobium meliloti
enters into beneficial symbiotic interactions with
Medicago
species of legumes. Bacterial exopolysaccharides play critical signaling roles in infection thread initiation and growth during the early stages of root nodule formation. After endocytosis of
S. meliloti
by plant cells in the developing nodule, plant-derived nodule-specific cysteine-rich (NCR) peptides mediate terminal differentiation of the bacteria into nitrogen-fixing bacteroids. Previous transcriptional studies showed that the intensively studied cationic peptide NCR247 induces expression of the
exo
genes that encode the proteins required for succinoglycan biosynthesis. In addition, genetic studies have shown that some
exo
mutants exhibit increased sensitivity to the antimicrobial action of NCR247. Therefore, we investigated whether the symbiotically active
S. meliloti
exopolysaccharide succinoglycan can protect
S. meliloti
against the antimicrobial activity of NCR247. We discovered that high-molecular-weight forms of succinoglycan have the ability to protect
S. meliloti
from the antimicrobial action of the NCR247 peptide but low-molecular-weight forms of wild-type succinoglycan do not. The protective function of high-molecular-weight succinoglycan occurs via direct molecular interactions between anionic succinoglycan and the cationic NCR247 peptide, but this interaction is not chiral. Taken together, our observations suggest that
S. meliloti
exopolysaccharides not only may be critical during early stages of nodule invasion but also are upregulated at a late stage of symbiosis to protect bacteria against the bactericidal action of cationic NCR peptides. Our findings represent an important step forward in fully understanding the complete set of exopolysaccharide functions during legume symbiosis.

IMPORTANCE
Symbiotic interactions between rhizobia and legumes are economically important for global food production. The legume symbiosis also is a major part of the global nitrogen cycle and is an ideal model system to study host-microbe interactions. Signaling between legumes and rhizobia is essential to establish symbiosis, and understanding these signals is a major goal in the field. Exopolysaccharides are important in the symbiotic context because they are essential signaling molecules during early-stage symbiosis. In this study, we provide evidence suggesting that the
Sinorhizobium meliloti
exopolysaccharide succinoglycan also protects the bacteria against the antimicrobial action of essential late-stage symbiosis plant peptides.
RIG-I-Like Receptor and Toll-Like Receptor Signaling Pathways Cause Aberrant Production of Inflammatory Cytokines/Chemokines in a Severe Fever with Thrombocytopenia Syndrome Virus Infection Mouse Model
Authors: Yamada Shintaro , Shimojima Masayuki , Narita Ryo , Tsukamoto Yuta , Kato Hiroki , Saijo Masayuki , Fujita Takashi 
Published: April 2018

ABSTRACT

Severe fever with thrombocytopenia syndrome (SFTS) is an emerging infectious disease caused by a tick-borne phlebovirus of the family
Bunyaviridae
, SFTS virus (SFTSV). Wild-type and type I interferon (IFN-I) receptor 1-deficient (IFNAR1
−/−
) mice have been established as nonlethal and lethal models of SFTSV infection, respectively. However, the mechanisms of IFN-I production
in vivo
and the factors causing the lethal disease are not well understood. Using bone marrow-chimeric mice, we found that IFN-I signaling in hematopoietic cells was essential for survival of lethal SFTSV infection. The disruption of IFN-I signaling in hematopoietic cells allowed an increase in viral loads in serum and produced an excess of multiple inflammatory cytokines and chemokines. The production of IFN-I and inflammatory cytokines was abolished by deletion of the signaling molecules IPS-1 and MyD88, essential for retinoic acid-inducible gene I (RIG-I)-like receptor (RLR) and Toll-like receptor (TLR) signaling, respectively. However, IPS-1
−/−
MyD88
−/−
mice exhibited resistance to lethal SFTS with a moderate viral load in serum. Taken together, these results indicate that adequate activation of RLR and TLR signaling pathways under low to moderate levels of viremia contributed to survival through the IFN-I-dependent antiviral response during SFTSV infection, whereas overactivation of these signaling pathways under high levels of viremia resulted in abnormal induction of multiple inflammatory cytokines and chemokines, causing the lethal disease.

IMPORTANCE
SFTSV causes a severe infectious disease in humans, with a high fatality rate of 12 to 30%. To know the pathogenesis of the virus, we need to clarify the innate immune response as a front line of defense against viral infection. Here, we report that a lethal animal model showed abnormal induction of multiple inflammatory cytokines and chemokines by an uncontrolled innate immune response, which triggered the lethal SFTS. Our findings suggest a new strategy to target inflammatory humoral factors to treat patients with severe SFTS. Furthermore, this study may help the investigation of other tick-borne viruses.
Fungal Morphogenesis, from the Polarized Growth of Hyphae to Complex Reproduction and Infection Structures
Authors: Riquelme Meritxell , Aguirre Jesús , Bartnicki-García Salomon , Braus Gerhard H. , Feldbrügge Michael , Fleig Ursula , Hansberg Wilhelm , Herrera-Estrella Alfredo , Kämper Jörg , Kück Ulrich , Mouriño-Pérez Rosa R. , Takeshita Norio , Fischer Reinhard 
Published: April 2018

SUMMARYFilamentous fungi constitute a large group of eukaryotic microorganisms that grow by forming simple tube-like hyphae that are capable of differentiating into more-complex morphological structures and distinct cell types. Hyphae form filamentous networks by extending at their tips while branching in subapical regions. Rapid tip elongation requires massive membrane insertion and extension of the rigid chitin-containing cell wall. This process is sustained by a continuous flow of secretory vesicles that depends on the coordinated action of the microtubule and actin cytoskeletons and the corresponding motors and associated proteins. Vesicles transport cell wall-synthesizing enzymes and accumulate in a special structure, the Spitzenkörper, before traveling further and fusing with the tip membrane. The place of vesicle fusion and growth direction are enabled and defined by the position of the Spitzenkörper, the so-called cell end markers, and other proteins involved in the exocytic process. Also important for tip extension is membrane recycling by endocytosis via early endosomes, which function as multipurpose transport vehicles for mRNA, septins, ribosomes, and peroxisomes. Cell integrity, hyphal branching, and morphogenesis are all processes that are largely dependent on vesicle and cytoskeleton dynamics. When hyphae differentiate structures for asexual or sexual reproduction or to mediate interspecies interactions, the hyphal basic cellular machinery may be reprogrammed through the synthesis of new proteins and/or the modification of protein activity. Although some transcriptional networks involved in such reprogramming of hyphae are well studied in several model filamentous fungi, clear connections between these networks and known determinants of hyphal morphogenesis are yet to be established.
Trainees success rates with intubation to suction meconium at birth
Authors: Robinson Marie-Ève , Diaz Ileana , Barrowman Nicholas James , Huneault-Purney Nicole , Lemyre Brigitte , Rouvinez-Bouali Nicole 
Published: April 2018

ObjectivesTo assess the success rate and main reasons for failure of intubation performed by medical trainees to suction meconium below the vocal cords in non-vigorous infants delivered at ≥36 week gestation.DesignWe conducted a prospective cohort study involving 54 residents and nine neonatology fellows in a Canadian level 3 neonatal intensive care unit. Endotracheal intubation to suction meconium was performed using a videolaryngoscope, the video screen being covered during the procedure. All videos were reviewed by two experts blinded to the procedure and to the identity of the trainee.ResultsSixteen videos were available to review between July 2014 and March 2016. Intubation success rate assessed by the reviewers was 6%, compared with 21% as assessed by the trainees. The most common reasons for intubation failure were an improper view of the glottis (87%) and meconium or secretions obscuring the view (67%). 36 % of the time, the trainees identified different reasons for intubation failure than the reviewers.ConclusionSuccess rate of neonatal intubation to suction meconium was much lower than the success rate reported on infants without meconium. Teaching should be geared towards the most common reasons for intubation failure, possibly using video-based teaching.
High prevalence rate of digestive tract bacteria in duodenoscopes: a nationwide study
Authors: Rauwers Arjan W , Voor in ’t holt Anne F , Buijs Jolanda G , de Groot Woutrinus , Hansen Bettina E , Bruno Marco J , Vos Margreet C 
Published: April 2018

ObjectiveIncreasing numbers of outbreaks caused by contaminated duodenoscopes used for Endoscopic Retrograde Cholangiopancreatography (ERCP) procedures have been reported, some with fatal outcomes. We conducted a nationwide cross-sectional study to determine the prevalence of bacterial contamination of reprocessed duodenoscopes in The Netherlands.DesignAll 73 Dutch ERCP centres were invited to sample ≥2 duodenoscopes using centrally distributed kits according to uniform sampling methods, explained by video instructions. Depending on duodenoscope type, four to six sites were sampled and centrally cultured. Contamination was defined as (1) any microorganism with ≥20 colony forming units (CFU)/20 mL (AM20) and (2) presence of microorganisms with gastrointestinal or oral origin, independent of CFU count (MGO).ResultsSixty-seven out of 73 centres (92%) sampled 745 sites of 155 duodenoscopes. Ten different duodenoscope types from three distinct manufacturers were sampled including 69 (46%) Olympus TJF-Q180V, 43 (29%) Olympus TJF-160VR, 11 (7%) Pentax ED34-i10T, 8 (5%) Pentax ED-3490TK and 5 (3%) Fujifilm ED-530XT8. Thirty-three (22%) duodenoscopes from 26 (39%) centres were contaminated (AM20). On 23 (15%) duodenoscopes MGO were detected, including Enterobacter cloacae, Escherichia coli, Klebsiella pneumonia and yeasts. For both definitions, contamination was not duodenoscope type dependent (p values: 0.20 and higher).ConclusionIn 39% of all Dutch ERCP centres, at least one AM20-contaminated patient-ready duodenoscope was identified. Fifteen per cent of the duodenoscopes harboured MGO, indicating residual organic material of previous patients, that is, failing of disinfection. These results suggest that the present reprocessing and process control procedures are not adequate and safe.
Role of high-throughput sequencing in the diagnosis of cutaneous T-cell lymphoma
Authors: Rea Bryan , Haun Paul , Emerson Ryan , Vignali Marissa , Farooqi Midhat , Samimi Sara , Elenitsas Rosalie , Kirsch Ilan , Bagg Adam 
Published: April 2018

AimsSubstantial clinicopathological overlap exists between cutaneous T-cell lymphoma (CTCL) and benign conditions, leading to diagnostic difficulties. We sought to delineate the utility of high-throughput sequencing (HTS) across a spectrum of histological findings in CTCL and reactive mimics.MethodsOne hundred skin biopsies obtained for clinical concern for CTCL were identified, comprising 25 cases each from four histological categories: ‘definitive CTCL’, ‘atypical lymphoid infiltrate, concerning for CTCL’, ‘atypical lymphoid infiltrate, favour reactive’ or ‘reactive lymphoid infiltrate’. T-cell receptor gamma chain gene (TRG) PCR and T-cell receptor beta chain gene HTS were performed on both skin biopsy and concurrently collected peripheral blood; most peripheral blood samples were also analysed by flow cytometry.ResultsHistologically defined CTCL specimens had significantly higher clonality scores and T-cell fractions via HTS than all other groups (all p<0.002 and p<0.03, respectively). HTS was more diagnostically specific than TRG PCR in skin (100% vs 88%), while diagnostic sensitivity (68% vs 72%) and accuracy (84% vs 80%) were similar. TRG PCR and flow cytometry performed on blood were the least diagnostically useful assays. Some identically sized peaks detected by TRG PCR in concurrent skin and peripheral blood specimens were non-identical by HTS analysis.ConclusionsHTS, by assessing both clonality and T-cell fractions in skin biopsies, is a powerful tool to aid in the diagnosis of CTCL. It is more specific than TRG PCR in distinguishing definitive CTCL from reactive and indeterminate histology. Identically sized peaks by TRG PCR, typically interpreted to be clonally related, are not always clonally identical by sequencing.