bluuebunny/crossref_metadata_2025 huggingface dataset:
Haste makes waste—Should current guideline recommendations for initiation of renal replacement therapy for acute kidney injury be changed?
Authors: Vanmassenhove Jill , Vanholder Raymond , Van Biesen Wim , Lameire Norbert
Published: April 2018

There is broad consensus among guideline organizations that renal replacement therapy (RRT) should not be delayed in case of life‐threatening conditions. However, in case of severe acute kidney injury (AKI) without these conditions, it is unclear whether immediate RRT has an advantage over delayed RRT. Two recently published randomized controlled trials (AKIKI and ELAIN) with seemingly opposite results have reignited the discussion whether guideline recommendations on initiation strategies in severe AKI should be adapted. This editorial discusses RRT initiation strategies in severe AKI, based on recent literature and highlights the potential advantages and disadvantages of immediate vs delayed start. Overall, evidence in favor of immediate compared to delayed strategies is sparse and there is wide heterogeneity across studies making it difficult to draw firm conclusions. RRT should not be delayed in case of refractory hyperkalemia, severe metabolic acidosis or pulmonary edema resistant to diuretics. In all other cases, a delayed strategy seems justified and might enhance renal recovery. RRT is not a “it doesn't hurt to try” technique and can expose the patient to a higher risk of bleeding, hemodynamic problems, under‐dosing of antibiotics, loss of nutrients, catheter‐related complications and the uncertain effects of blood‐membrane interactions. There is no compelling reason to change current guideline recommendations and research focus should shift toward the development of algorithms as a decision aid tool for RRT initiation in severe AKI.
Simulation of Bayes' rule by means of Monte Carlo method
Authors: Gangur Mikuláš , Svoboda Milan
Published: April 2018

This contribution shows a simple implementation of Monte Carlo simulation method when presenting Bayes' rule. The implementation is carried out in the environment of Microsoft Excel spreadsheets by means of a generator of random numbers. The empiric results gained by simulation serve to confirm the correctness of the chosen procedures in calculations using Bayes' formula.
Video‐assisted thoracoscopic thoracic duct sealing is inconsistent when performed with a bipolar vessel‐sealing device in healthy cats
Authors: Mitchell Jeffrey W. , Mayhew Philipp D. , Johnson Eric G. , Steffey Michele A. , Pascoe Peter J.
Published: April 2018

Objective

To describe a technique for video‐assisted thoracoscopic (VATS) thoracic duct ligation (TDL) in normal cats with a bipolar vessel‐sealing device and to assess durability of the seal.

Study Design

Prospective case series.

Animals

Six healthy research cats.

Methods

Cats were placed under anesthesia for computed tomography lymphangiography (CTLA) to identify thoracic duct anatomy. On the basis of CTLA findings, cats were positioned in either right or left lateral recumbency for a 3‐port VATS TDL. Thoracic duct branches were dissected from the aorta after subcutaneous indirect near‐infrared fluorescence (NIRF) lymphography with indocyanine green was performed to optimize detection. A vessel‐sealing device was used to seal each thoracic duct in 1 or more locations. Postattenuation, indirect NIRF lymphography was repeated to confirm complete occlusion of thoracic duct flow. CTLA was repeated in all cats 3 months postoperatively.

Results

The thoracic duct was surgically approached from the right in 3 cats and from the left in 3 cats. A median of 2.5 (range 1‐6) TDL seal sites were applied. In 2 cats, leakage of chyle was detected during dissection. At 3 months postoperatively, CTLA confirmed reestablished chylous flow in 5 of 6 cats, appearing to occur through recanalization of previously sealed sites rather than through development of de novo lymphatic vessels.

Conclusion

VATS TDL is feasible in cats, although the variable and delicate nature of feline thoracic duct anatomy should be considered preoperatively.

Clinical significance

Bipolar vessel‐sealing devices are not a durable modality for thoracic duct sealing in healthy cats in a seal only fashion.
Challenges to controlling rabies in skunk populations using oral rabies vaccination: A review
Authors: Wohlers A. , Lankau E. W. , Oertli E. H. , Maki J.
Published: April 2018

Controlling rabies in skunk populations is an important public health concern in many parts of the United States due to the potential for skunk rabies outbreaks in urban centres and the possible role for skunks in raccoon rabies variant circulation. Oral rabies vaccination (ORV) programmes have supported wildlife rabies control efforts globally but using ORV to control rabies in skunk populations has proven more challenging than with other target species, like foxes, coyotes and raccoons. A review of published studies found that some ORV constructs are immunogenic in skunks and protect against virulent rabies virus challenges, especially when delivered by direct installation into the oral cavity. However, in field ORV programmes using currently available vaccine‐bait formats and distribution methods targeting other rabies reservoir species, skunks often fail to seroconvert. Field effectiveness of ORV in skunks appears to be limited by poor bait uptake or inadequate ingestion of vaccine rather than from poor vaccine efficacy. Observations of captive skunks revealed vaccine spillage when handling and biting into baits such that modification of bait formats might improve field effectiveness. In addition, a dose–response relationship between bait distribution density and post‐baiting seroconversion among skunks was observed across the limited number of field studies. Additional research is needed to identify opportunities to modify ORV baits and distribution strategies to improve the viability of ORV as a rabies control strategy in skunks.
A penalized likelihood approach to model the annual maximum flow with small sample sizes
Authors: Kahal Musakkal Nur Farhanah , Chin Su Na , Ghazali Khadizah , Gabda Darmesah
Published: April 2018

The aim of this study is to model the annual maximum flow of several sites in Sabah with small sample sizes using the generalized extreme value (GEV) distribution. Previous studies have shown that the standard method of maximum likelihood estimates would give a poor estimation of the GEV parameters and quantiles for small data set. This study will consider the penalized likelihood estimates as an alternative method to improve the inference over the standard method and retains the modeling flexibility. As comparisons, we will illustrate the results of both methods to model the annual maximum flow in Sabah. The results show the implementation of the penalty function had the same effect to the GEV parameter estimates as suggested by previous studies.
Rainfall, evapotranspiration and rainfall deficit trend in Alor Setar, Malaysia
Authors: Ahmad Aimi Athirah , Yusof Fadhilah , Mispan Muhamad Radzali , Kamaruddin Hasliana
Published: April 2018

Rainfall and potential evapotranspiration are important variables in water balance study. Rainfall data were obtained from Malaysian Meteorological Department while estimates of potential evapotranspiration were calculated using Penman-Monteith method. Trend analysis of monthly and annual rainfall, potential evapotranspiration and rainfall deficit are essential to manage irrigation system in agricultural systems. This is because changes in trend of these parameters may affect the water cycle and ecosystem. Annual and monthly values of these variables were analysed from 1980-2009. Results indicated  increasing trends of 16.2 mm yr-1 and 3.01 mm yr-1 for both annual rainfall and potential evapotranspiration, respectively. Consequently, these trends resulted in annual rainfall deficit of 1.69 mm per year.
Spatial grouping of homogeneous river flow process in Johor
Authors: Mansor Nur Syazwin , Ahmad Norhaiza
Published: April 2018

This study identifies the spatial grouping of homogeneous river flow process on eight rivers in Johor based on river discharge records of 28 years. A clustering approach using a nonlinear dissimilarity measure called Dynamic Time Warping (DTW) is used to detect the similarity between these eight rivers. The clustering results validated by an internal validity measure, C-index shows two distinct groups of rivers: Cluster 1 consist of Sungai Lenik, Sungai Segamat, Sungai Bekok, and Sungai Muar; Cluster 2 consist of Sungai Sayong, Sungai Lenggor, Sungai Johor, and Sungai Kahang. This two-cluster solution are stable and interpretable with reference to spatial variations and can be distinguish by their geographical location in the peninsular.
Modelling of Newtonian blood flow through a bifurcated artery with the presence of an overlapping stenosis
Authors: Zain Norliza Mohd , Ismail Zuhaila
Published: April 2018

Mathematical modelling of blood flow is developed by treating the blood as a Newtonian fluid. In this study, stenosis has been accounted as an overlapping shaped in two-dimensional Cartesian coordinate system. Blood are assumed as steady laminar flow, fully developed and incompressible which flowing through an arterial bifurcation where the wall considered rigid with no-slip condition. Galerkin weighted residual method is performed and a Matlab code is developed to solve the problem. To validate the code, comparison has been made with the results obtained by COMSOL Multiphysics. Results on the velocity profiles and the streamlines pattern are observed and discussed in details.
Global Canny algorithm based on Canny edge detector framework in magnetic resonance imaging
Authors: Tengku Alang Tengku Ahmad Iskandar , Swee Tan Tian , Hou Tan Jia , Meng Leong Kah , Malik Sameen Ahmed , Asari Muhammad Amir , Hussein Adil , Yaakub Azhany , Chai Hum Yan , Haron Juhara
Published: April 2018

Magnetic resonance imaging is an important modality in the diagnosis and pathology detection. Edge detection is used for image segmentation and feature extraction as part of the medical image analysis. There is no ideal and universal algorithm which performs perfectly under all conditions. Conventional Canny edge detector is not suitable to be used in Magnetic resonance images that contaminated by Rician noise. In this paper, we propose the use of customized non-local means into the Canny edge detector instead of Gaussian smoothing in the conventional Canny edge detector to effectively remove Rician noise while preserving edges in Magnetic resonance image of an internal organ. The result shows that our method can yield better edge detection than conventional method, with minimal false edge detection. The proposed method undergoes several attempts of parameter adjustment to detect true edges successfully using optimal parameter setting.
Study on empathetic-pain perception in brain induced by three levels of empathetic-pain perception stimuli
Authors: Md Yassin Siti Norhayati , Priya Utama Nugraha , Mohamad Salim Maheza Irna
Published: April 2018

Empathetic-pain perception is a divergence from empathy which is a pain perceived as a reflection of perception from others.  The study of empathetic-pain perception and empathy were always related with psychological disorder effecting social and humanity values.  The process involved in empathetic-pain perception formations in brain were believed to be different if induced by different level of empathetic-pain perception stimuli.  Therefore, this paper was aimed to study the processes involved in empathetic-pain perception formation by revealing the activation-time intervals and source location of the highest empathetic-pain perception intensity.  This study conducted an experiment to induce empathetic-pain perception on 16 participants using still pictures as visual-stimuli.  Electroencephalograph (EEG) recorded brain signal of the participants during the visual-stimuli presentations while the EEG signal were analysed using MATLAB® toolbox, EEGLAB.  Time/frequency decomposition in EEGLAB produces ERSP images which determines the activation-time intervals for empathetic-pain perception and, by performing source localization within the activation-time intervals using sLORETA, the source locations for most active processes in empathetic-pain perception were determined.  The processes involved in empathetic-pain perception formation in every level were ‘stimuli-learning’ and ‘memory-reconstructions’ by Posterior Cingulate BA 30, pain-regulation by either Postcentral Gyrus BA 2, Cingulate Gyrus BA 24 or both, and visual-stimuli and visual-memory processing by Lingual Gyrus at almost similar time intervals.  However, the processes were also performed by various brain areas to either perform attention-sustain process while managed working memory and self-control regulation by Middle Frontal Gyrus BA 46, mirror-neurons activation while processed attention information and emotions by Inferior Parietal Lobule BA 40, multisensory integration by Superior Temporal Gyrus BA 22, or motor-neurons activation to control the skeletal system respectively in every level by Paracentral Lobule BA 6 and Precentral Gyrus BA44.  In conclusion, the empathetic-pain perception formation process discovery were necessary to differentiate every affectional level of the empathetic-pain perception.
Single segment actuator using shape memory alloy for three-directional bending endoscopic tip
Authors: Abdul Kadir Muhammad Raihan , Dewi Dyah Ekashanti Octorina , Mohamed Ali Mohamed Sultan , Mohd Faudzi Ahmad ‘Athif
Published: April 2018

Shape Memory Alloy (SMA) is a specially fabricated alloy which is capable of altering its shape based on external stimuli. With this mechanism, SMA can be used as actuator with highly controlled maneuverability and flexibility. This study was aimed to design, fabricate, test and analyze an SMA actuator with three-directional bending capabilities. The design consisted of a set of SMA actuators with a pseudo-elastic alloy bias wire. A silicone rubber sheathe was fabricated to act as a heat buffer. The actuator was activated with a DC current between 0-900mA at 70% PWM duty cycle. Bending and heat tests resulted in positive bending of about 30° consistently while the instrument without the silicone rubber sheathe on the instrument. Temperature readings on the thermal camera are 40°C. With the silicone rubber sheathe, the bending angle is halved over the entire instrument, but with a smaller decrease in recorded temperature of the main bodies. This SMA-based actuator is prospectively used to improve the maneuverability and flexibility of an endoscopic tip.
Pulsatile flow simulation of patent ductus arteriosus to evaluate thrombosis factors on closure device
Authors: Ahmad Nurulnatisya , Taib Ishkrizat , Osman Kahar , Md Khudzari Ahmad Zahran
Published: April 2018

Transcatheter treatment using occlusion devices is the most common treatment used to treat the Patent Ductus Arteriosus (PDA). The occlusion device act as a physical barrier to blood flow in the duct which facilitates thrombogenesis and occludes the duct. Over the past 15 years, there have been significant developments in the devices used to close PDA. Various design of occlusion device affects the flow of blood in the duct. To improve the efficiency of the thrombogenesis on the surface of occlusion device and estimate the time needed to occludes the duct, it is important to simulate blood flow through different design of occlusion device. Two design was used which is the concave and convex shape of the occlusion device. Blood was simulated as Newtonian with the incompressible and laminar flow. A computational fluid dynamics (CFD) study has been done in pulsatile blood flow through the aortic arch and the occlusion device. The hemodynamic parameters that contribute to the thrombosis formation have been studied and showed that the convex shape yielded more TAWSSlow (< 0.5 Pa) magnitude (65.72%), generated 51.84% areas that exposed to high OSI and calculated 14.46% areas that exposed to RRT ≥ 10 Pa-1. While, concave shape yielded 13.21% of TAWSSlow (< 0.5 Pa), generated only 47.84% of areas that exposed to high OSI and calculated 14.46% areas that exposed to RRT ≥ 10 Pa-1. Therefore, from the preliminary work on PDA occlusion device, it is suggested that to promote thrombosis, the convex shape was much better compared to concave shape.
Phytochemical, cytotoxicity and antioxidant studies on the stem bark of Piper arborescens
Authors: Daniel Nicholas Anak , Ahmad Fasihuddin Badruddin , Assim Zaini , Pin Chua Hun
Published: April 2018

Phytochemical study on the stem bark of P. arborescens has isolated six secondary metabolites from the crude extracts by using column chromatography, while identification was performed by using Gas Chromatography - Mass Spectrometry (GC-MS), Nuclear Magnetic Resonance (NMR) and Fourier Transform Infrared (FTIR). The isolated metabolites were identified as caryophyllene oxide (1), α-bisabolol (2), benzamide 2-(methylamino) (3), 2-ethylpiperidine (4), piperine (5) and methyl eugenol (6). Toxicity test on the four crude extracts of P. arborescens shows a high cytotoxicity against Artemia salina brine shrimp with LC50 values ranging from 13.12 to 58.70 µg/mL. Greater cytotoxicity of the crude extracts of P. arborescens indicated the presence of potent cytotoxic components in this Piper spp. Antioxidant assay of P. arborescens against 2-diphenyl-1-picrylhydrazyl (DPPH) indicated moderate antioxidant activities of methanol, dichloromethane, chloroform and hexane crude extracts with EC50 values of 21.68, 23.82, 32.88 and 36.88 µg/mL, respectively.
The conjugacy class graph of some finite groups and its energy
Authors: Mahmoud Rabiha , Sarmin Nor Haniza , Erfanian Ahmad
Published: April 2018

The energy of a graph which is denoted by  is defined to be the sum of the absolute values of the eigenvalues of its adjacency matrix. In this paper we present the concepts of conjugacy class graph of dihedral groups and introduce the general formula for the energy of the conjugacy class graph of dihedral groups. The energy of any dihedral group of order   in different cases, depends on the parity of   is proved in this paper. Also we introduce the general formula for the conjugacy class graph of generalized quaternion groups and quasidihedral groups.
SPR sensor for detection of heavy metal ions: Manipulating the EM waves polarization modes
Authors: Mukhtar Wan Maisarah , Mohd Halim Razman , Ahmad Dasuki Karsono , Abdul Rashid Affa Rozana , Mohd Taib Nur Athirah
Published: April 2018

Water contamination by heavy metals is a common issue encountered in many countries due to industrial and urban wastes in water resources which give health and socio-economic impacts. This work is carried out to investigate the effect of EM wave polarization modes on the sensing properties of surface plasmon resonance (SPR) sensor in detecting heavy metal ions namely mercury (Hg) and plumbum (Pb). Three types of polarization modes such as p-polarized, s-polarized and circular-polarized light were introduced. Gold and silver thin films with thicknesses of 50nm were deposited on top of SPR layer system to excite surface plasmon polaritons (SPPs). The SPR curves were analyzed by studying the FWHM, Q-factor and angle shifting characteristics. We manage to prove theoretically that the SPR phenomena able to be created by using not only the p-polarized light, yet by employing a circular-polarized light. The sensor shows positive respond for both polarization modes, where the troughs were red-shifted about 23.78% as Pb was introduced on the top of the gold-coated SPR sensor.  The SPR angles were shifted about 24.45% as the sensor was exposed with Hg metal ions. Different response due to the presence of different analytes exhibits an excellent criteria of high selectivity sensor.  In conclusion, the combination of p-polarized light or circular-polarized light and gold thin film able to accentuate the significant role of SPR sensor in detecting heavy metal ions.
Modeling of lead (II) adsorption on sodium hydroxide treated rice husk: Fixed-bed studies
Authors: Garba Abdurrahman , Basri Hatijah , Nasri Noor Shawal , Siddiq Umar Hayatu , Abdul Rahman Abdul Rasheed
Published: April 2018

The treated rice husk has been evaluated as a sorbent for removing lead (II) from aqueous solutions in fixed-bed studies. In this paper, the effects of flow rate (3 and 9 mL/min), bed depth (0.9, 1.8 and 2.8 cm) and influent lead concentration of (5 and 20 mg/L) on the adsorption capacity of the adsorbent in a fixed-bed column were investigated. The highest adsorption capacity (78 %) on a 20 mg/L Pb (II) solution was achieved within a flow rate of 9 mL/min and a bed depth of 2.8 cm. The experimental data obtained from the adsorption process was correlated with the Thomas, Adams– Bohart and Yoon–Nelson models. The results of the parameters indicated Adams–Bohart model fitted well over the other models.
Adsorption of ammonia nitrogen by jackfruit (Artocarpus heterophyllus) seeds: Isotherms and kinetic modeling studies
Authors: Ibrahim Azreen , Yusof Lija , Yaser Abu Zahrim
Published: April 2018

Ammonia nitrogen (NH3 - N) is one of the common and toxic species of nitrogen and excess of it in waterway causes eutrophication, decreased in dissolved oxygen and toxic to aquatic organisms. This study aims to investigate the isotherm and kinetic modeling of adsorption of ammonia nitrogen from aqueous solution by using jackfruit (Artocarpus heterophyllus) seed. Batch equilibrium experiments were carried out at 60 minute of contact time with initial pH value of 7. The adsorption isotherm data fitted well with Langmuir model with correlation (R2) of 0.9809 and maximum monolayer adsorption capacitiy (Qe) of 3.94 mg/g. Meanwhile, the adsorption of NH3 - N follows pseudo second order with correlation (R2) values ranges from 0.62 to 0.96 for various concentrations. Besides, the adsorption capacity obtained from experiment also has the smallest difference with calculated adsorption capacity. This suggest that the adsorption is mainly governed by chemical process involving cations sharing or exchange between the adsorbent and NH3 - N in the solution. In conclusion, jackfruit seed can be used as adsorbent materials for ammonia nitrogen removal from aqueous solution.
Nursing quality indicator outcomes in hospitals with a Clinical Nurse Leader: a scoping review protocol
Authors: Sage Lauren , Harris Janet
Published: April 2018

Review question/objective:

What nursing quality indicator outcomes related to nosocomial infections have been identified in studies reporting upon care of patients by Clinical Nurse Leaders?

The objective of this scoping review is to explore existing literature related to nursing quality indicator outcomes specific to nosocomial infections in studies reporting upon care of patients by Clinical Nurse Leaders, examine and conceptually map the evidence, and identify any gaps.
Patient involvement interventions for older adults in transitional care between hospital and primary care: a scoping review protocol
Authors: Ludvigsen Mette Spliid , Høy Bente
Published: April 2018

Review question/objective:

The objective of this scoping review is to identify and map existing evidence of patient involvement interventions for older adults in transitional care between hospital and primary care.

The questions of this review are:

What types of patient involvement interventions for older adults in transitional care have been described?

Which theories, principles, components, methods, outcome measures and suggested practical applications of patient involvement interventions for older adults in transitional care have been described?

Which levels of patient involvement for older adults in transitional care interventions can be identified?

What are the key issues encountered by healthcare providers related to patient involvement interventions for older adults in transitional care?

What evidence gaps in patient involvement interventions for older adults in transitional care can be identified?
Men's perceptions of the impact of the physical consequences of a radical prostatectomy on their quality of life: a qualitative systematic review
Authors: Carrier Judith , Edwards Deborah , Harden Jane
Published: April 2018

Objective:

To identify men's perceptions of the impact of the physical consequences of a radical prostatectomy on their quality of life.

Introduction:

Prostate cancer is the most common male cancer and second most common cause of cancer death of men in the Western world. Compared to other prostate cancer treatments, trials report worse urinary incontinence and sexual function and similar bowel function among men with prostate-specific antigen detected prostate cancer who underwent radicalized prostatectomy.

Inclusion criteria:

This review included men of all ages and nationalities who had undergone a radical prostatectomy as treatment for any stage of prostate cancer. It considered studies that investigated:

The physical consequences of radical prostatectomy and its impact on quality of life and life experience as identified by the men.

The psychosocial implications of the identified physical consequences of radical prostatectomy as identified by the men.

Any setting where the topic was addressed with participants meeting the inclusion criteria was included. The review considered studies that focused on qualitative data including, but not limited to: phenomenology, grounded theory, ethnography and action research. Studies were included if they reported results relating to one or more of the phenomena of interest. Studies not written in English were excluded.

Methods:

The search strategy aimed to find published studies from six databases from database inception to November 2017. Methodological quality of studies was independently assessed by two reviewers using the standardized JBI Critical Appraisal Checklist for Qualitative Research. For data extraction, the standardized Joanna Briggs Institute System for the Unified Management, Assessment and Review of Information (JBI SUMARI) data extraction tool was used. A meta-aggregation was undertaken and the final synthesis of the findings was reached through discussion. Results are presented as five aggregated qualitative syntheses.

Results:

Nineteen qualitative studies were included in the review. The five synthesized findings were:

1. Urinary incontinence is a significant problem for which men feel ill prepared.

2. The impact of erectile dysfunction on men post-radicalized prostatectomy.

3. Acceptance of the side-effects of radical prostatectomy.

4. The impact of erectile dysfunction on relationships.

5. Physical and psychosocial support are perceived to be essential for men to deal with the physical impact of radical prostatectomy on their quality of life.

Conclusions:

Urinary incontinence and erectile dysfunction are significant side-effects of radical prostatectomy which have a negative impact on men's quality of life for which they feel ill prepared, and physical and psychosocial support is essential.
Effectiveness and safety of pharmacological sedation for aggressive or agitated adult patients in a prehospital emergency situation: a systematic review protocol
Authors: Raab Martin , Lizarondo Lucylynn , Brook Carol
Published: April 2018

Review question/objective:

The objective of this systematic review is to identify, evaluate and synthesize evidence on the effectiveness and safety of pharmacological sedation for aggressive or agitated adult patients in a prehospital emergency situation.
Integration of nicotinic acid adenine dinucleotide phosphate (NAADP)‐dependent calcium signalling
Authors: Guse Andreas H. , Diercks Björn‐Philipp
Published: April 2018

Nicotinic acid adenine dinucleotide phosphate (NAADP) is currently the most potent endogenous Ca2+ mobilizing second messenger. Upon specific extracellular stimulation, rapid production of NAADP has been observed in different cell types from sea urchin eggs to mammalian cells. More than 20 years after the discovery of NAADP, there is still controversy surrounding its metabolism and target receptors/ion channels and organelles. This article briefly reviews recent developments in the NAADP field. Besides the metabolism of NAADP, this review focuses on assumed organelles and putative targets, e.g. ion channels, with special emphasis on ryanodine receptor type 1 (RyR1) and two‐pore channels (TPCs). The role of NAADP as a Ca2+ trigger is also discussed and the importance of NAADP in the formation of initial Ca2+ microdomains is highlighted.

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A nanoscale reorganization of the IL-15 receptor is triggered by NKG2D in a ligand-dependent manner
Authors: Bálint Štefan , Lopes Filipa B. , Davis Daniel M.
Published: April 2018

The activating receptor NKG2D clusters with the IL-15 receptor in NK cells upon stimulation with ULBP2.
HIV Protease-Generated Casp8p41, When Bound and Inactivated by Bcl2, Is Degraded by the Proteasome
Authors: Natesampillai Sekar , Cummins Nathan W. , Nie Zilin , Sampath Rahul , Baker Jason V. , Henry Keith , Pinzone Marilia , O'Doherty Una , Polley Eric C. , Bren Gary D. , Katzmann David J. , Badley Andrew D.
Published: April 2018

HIV protease is known to cause cell death, which is dependent upon cleavage of procaspase 8. HIV protease cleavage of procaspase 8 generates Casp8p41, which directly binds Bak with nanomolar affinity, causing Bak activation and consequent cell death. Casp8p41 can also bind Bcl2 with nanomolar affinity, in which case cell death is averted. Central memory CD4 T cells express high levels of Bcl2, possibly explaining why those cells do not die when they reactivate HIV. Here, we determine that the Casp8p41-Bcl2 complex is polyubiquitinated and degraded by the proteasome. Ixazomib, a proteasome inhibitor in clinical use, blocks this pathway, increasing the abundance of Casp8p41 and causing more cells to die in a Casp8p41-dependent manner.

IMPORTANCE
The Casp8p41 pathway of cell death is unique to HIV-infected cells yet is blocked by Bcl2. Once bound by Bcl2, Casp8p41 is polyubiquitinated and degraded by the proteasome. Proteasome inhibition blocks degradation of Casp8p41, increasing Casp8p41 levels and causing more HIV-infected cells to die.
Colesevelam attenuates cholestatic liver and bile duct injury in Mdr2−/− mice by modulating composition, signalling and excretion of faecal bile acids
Authors: Fuchs Claudia Daniela , Paumgartner Gustav , Mlitz Veronika , Kunczer Victoria , Halilbasic Emina , Leditznig Nadja , Wahlström Annika , Ståhlman Marcus , Thüringer Andrea , Kashofer Karl , Stojakovic Tatjana , Marschall Hanns-Ulrich , Trauner Michael
Published: April 2018

Background and aims

Interruption of the enterohepatic circulation of bile acids (BAs) may protect against BA-mediated cholestatic liver and bile duct injury. BA sequestrants are established to treat cholestatic pruritus, but their impact on the underlying cholestasis is still unclear. We aimed to explore the therapeutic effects and mechanisms of the BA sequestrant colesevelam in a mouse model of sclerosing cholangitis.

Methods

Mdr2−/− mice received colesevelam for 8 weeks. Gene expression profiles of BA homeostasis, inflammation and fibrosis were explored in liver, intestine and colon. Hepatic and faecal BA profiles and gut microbiome were analysed. Glucagon-like peptide 1 (GLP-1) levels in portal blood were measured by ELISA. Furthermore, Mdr2−/− mice as well as wild-type 3,5-diethoxy-carbonyl-1,4-dihydrocollidine-fed mice were treated with GLP-1-receptor agonist exendin-4 for 2 weeks prior to analysis.

Results

Colesevelam reduced serum liver enzymes, BAs and expression of proinflammatory and profibrogenic markers. Faecal BA profiling revealed increased levels of secondary BAs after resin treatment, while hepatic and biliary BA composition showed a shift towards more hydrophilic BAs. Colonic GLP-1 secretion, portal venous GLP-1 levels and intestinal messenger RNA expression of gut hormone Proglucagon were increased, while ileal Fgf15 expression was abolished by colesevelam. Exendin-4 treatment increased bile duct mass without promoting a reactive cholangiocyte phenotype in mouse models of sclerosing cholangitis. Microbiota analysis showed an increase of the phylum δ-Proteobacteria after colesevelam treatment and a shift within the phyla Firmicutes from Clostridiales to Lactobacillus.

Conclusion

Colesevelam increases faecal BA excretion and enhances BA conversion towards secondary BAs, thereby stimulating secretion of GLP-1 from enteroendocrine L-cells and attenuates liver and bile duct injury in Mdr2−/− mice.
Abundance of the arbuscular mycorrhizal fungal taxa associated with the roots and rhizosphere soil of different durum wheat cultivars in the Canadian prairies
Authors: Ellouze Walid , Hamel Chantal , Singh Asheesh K. , Mishra Vachaspati , DePauw Ron M. , Knox Ron E.
Published: April 2018

Understanding the variation in how wheat genotypes shape their arbuscular mycorrhizal (AM) fungal communities in a prairie environment is foundational to breeding for enhanced AM fungi–wheat interactions. The AM fungal communities associated with 32 durum wheat genotypes were described by pyrosequencing of amplicons. The experiment was set up at two locations in the Canadian prairies. The intensively managed site was highly dominated by Funneliformis. Genotype influenced the AM fungal community in the rhizosphere soil, but there was no evidence of a differential genotype effect on the AM fungal community of durum wheat roots. The influence of durum wheat genotype on the AM fungal community of the soil was less important at the intensively managed site. Certain durum wheat genotypes, such as Strongfield, Plenty, and CDC Verona, were associated with high abundance of Paraglomus, and Dominikia was undetected in the rhizosphere of the recent cultivars Enterprise, Eurostar, Commander, and Brigade. Genetic variation in the association of durum wheat with AM fungi suggests the possibility of increasing the sustainability of cropping systems through the use of durum wheat genotypes that select highly effective AM fungal taxa residing in the agricultural soils of the Canadian prairies.
Underwater unidirectional acoustic transmission through a plate with bilateral asymmetric gratings
Authors: Song Ailing , Chen Tianning , Wang Xiaopeng , Xi Yanhui , Liang Qingxuan
Published: April 2018

In this paper, a novel underwater unidirectional acoustic transmission (UAT) device consisting of a plate with bilateral asymmetric gratings is proposed and numerically investigated. The transmission spectra, the acoustic intensity field distributions, and the displacement field distributions are numerically calculated based on the finite element method. The transmission spectra show that the proposed device exhibits different UAT effects in three bands. The acoustic intensity field distributions demonstrate that the proposed device can realize UAT, which agree well with the transmission spectra. The mechanism is discussed by analyzing the displacement field distributions, and the UAT is attributed to the symmetric mode excited in brass plate. Furthermore, the effects of the lattice constant, the upper slit width, and the lower slit width on bands are discussed. Our design provides a good reference for designing underwater UAT devices and has potential applications in some fields, such as medical ultrasonic devices, acoustic barrier, and noise insulation.
On divisibility between Alexander polynomials of Turk’s head links
Authors: Takemura Atsushi
Published: April 2018

We show that for any positive integers [Formula: see text] and [Formula: see text], the Alexander polynomial of the [Formula: see text]-Turk’s head link is divisible by that of the [Formula: see text]-Turk’s head link.
Tile number and space-efficient knot mosaics
Authors: Heap Aaron , Knowles Douglas
Published: April 2018

In this paper, we introduce the concept of a space-efficient knot mosaic. That is, we seek to determine how to create knot mosaics using the least number of non-blank tiles necessary to depict the knot. This least number is called the tile number of the knot. We determine strict bounds for the tile number of a knot in terms of the mosaic number of the knot. We also determine the tile number of several knots and provide space-efficient knot mosaics for each of them.
Droplet breakup in the liquid drop model with background potential
Authors: Alama Stan , Bronsard Lia , Choksi Rustum , Topaloglu Ihsan
Published: April 2018

We consider a variant of Gamow’s liquid drop model, with a general repulsive Riesz kernel and a long-range attractive background potential with weight [Formula: see text]. The addition of the background potential acts as a regularization for the liquid drop model in that it restores the existence of minimizers for arbitrary mass. We consider the regime of small [Formula: see text] and characterize the structure of minimizers in the limit [Formula: see text] by means of a sharp asymptotic expansion of the energy. In the process of studying this limit we characterize all minimizing sequences for the Gamow model in terms of “generalized minimizers”.
Concentration behavior of ground state solutions for a fractional Schrödinger–Poisson system involving critical exponent
Authors: Yang Zhipeng , Yu Yuanyang , Zhao Fukun
Published: April 2018

We are concerned with the existence and concentration behavior of ground state solutions of the fractional Schrödinger–Poisson system with critical nonlinearity [Formula: see text] where [Formula: see text] is a small parameter, [Formula: see text], [Formula: see text], [Formula: see text] denotes the fractional Laplacian of order [Formula: see text] and satisfies [Formula: see text]. The potential [Formula: see text] is continuous and positive, and has a local minimum. We obtain a positive ground state solution for [Formula: see text] small, and we show that these ground state solutions concentrate around a local minimum of [Formula: see text] as [Formula: see text].
Asymptotics for optimizers of the fractional Hardy–Sobolev inequality
Authors: Marano Salvatore A. , Mosconi Sunra J. N.
Published: April 2018

The existence of optimizers [Formula: see text] in the space [Formula: see text], with differentiability order [Formula: see text], for the Hardy–Sobolev inequality is established through concentration-compactness. The asymptotic behavior [Formula: see text] as [Formula: see text] and the summability information [Formula: see text] for all [Formula: see text] are then obtained. Such properties turn out to be optimal when [Formula: see text], in which case optimizers are explicitly known.
The nilpotent variety of W(1;n)p is irreducible
Authors: Chen Cong
Published: April 2018

In the late 1980s, Premet conjectured that the nilpotent variety of any finite dimensional restricted Lie algebra over an algebraically closed field of characteristic [Formula: see text] is irreducible. This conjecture remains open, but it is known to hold for a large class of simple restricted Lie algebras, e.g. for Lie algebras of connected algebraic groups, and for Cartan series [Formula: see text] and [Formula: see text]. In this paper, with the assumption that [Formula: see text], we confirm this conjecture for the minimal [Formula: see text]-envelope [Formula: see text] of the Zassenhaus algebra [Formula: see text] for all [Formula: see text].
A Hybrid Method for Density-Related Topology Optimization
Authors: Xiao Mi , Chu Sheng , Gao Liang , Li Hao
Published: April 2018

In this study, a hybrid method for density-related topology optimization is proposed, which consists of two parts: the discrete level-set method (LSM) based on solid isotropic material with penalization (SIMP) and the structural boundary extraction method based on support vector machine (SVM). In the hybrid method, the SIMP method is implemented to create new holes which are inserted into the topological structure obtained by the discrete LSM. SVM is utilized for extracting the boundary of the structure obtained by the SIMP-based discrete LSM. Based on the clear boundary extracted by SVM, a smooth boundary can be further obtained after data filtering. Four numerical examples are used to test the advantages of the hybrid method.
Optimizing the Geometric Parameters of Cutting Edge for the Finishing Machining of 30CR Alloy Steel
Authors: Jiang Feng , Guo Bicheng , Liao Tongkai , Wang Fuzeng , Cheng Xin , Yan Lan , Xie Hong
Published: April 2018

In order to optimize the geometric parameters of cutting edge for the finishing machining of 30Cr alloy steel, a two-dimensional (2D) finite element (FE) model of orthogonal cutting was built with FE software AdvantEdge. The optimized methodology of the cutting edge geometric parameters was likewise proposed based on the simulated results. Thereafter, the geometric parameters of the cutting edge were optimized based on a comprehensive criterion that combines chip deformation coefficient and tool stress. The chip deformation coefficient indirectly determines the surface roughness, whereas tool stress determines tool wear, thereby affecting the dimensional precision of the components. The rake angle ranges from 12[Formula: see text] to 20[Formula: see text], while the cutting edge radius ranges from 12[Formula: see text][Formula: see text]m to 20[Formula: see text][Formula: see text]m in the optimization process. The optimal rake angle for the finishing machining 30Cr alloy steel is 16[Formula: see text], while the optimal cutting edge radius is 14[Formula: see text][Formula: see text]m with a given relief angle of 7[Formula: see text].
Perfect fluid Bianchi type-I cosmological models with time-dependent cosmological term Λ
Authors: Singh J. P. , Baghel Prashant S. , Singh Abhay
Published: April 2018

We present perfect fluid Bianchi type-I cosmological models with time-dependent cosmological term [Formula: see text]. Exact solutions of the Einstein’s field equations are presented via a suitable functional form for Hubble parameter [Formula: see text], which yields a model of the universe that represents initially decelerating and late-time accelerating expansion. We discuss, in the context of some vacuum decay laws, cosmological implications of the corresponding solutions. The physical and geometrical features of the models are also discussed.
Covariant-differential formulation of Lagrangian field theory
Authors: Canarutto Daniel
Published: April 2018

Building on the Utiyama principle we formulate an approach to Lagrangian field theory in which exterior covariant differentials of vector-valued forms replace partial derivatives, in the sense that they take up the role played by the latter in the usual jet bundle formulation. Actually a natural Lagrangian can be written as a density on a suitable “covariant prolongation bundle”; the related momenta turn out to be natural vector-valued forms, and the field equations can be expressed in terms of covariant exterior differentials of the momenta. Currents and energy-tensors naturally also fit into this formalism. The examples of bosonic fields and spin one-half fields, interacting with non-Abelian gauge fields, are worked out. The “metric-affine” description of the gravitational field is naturally included, too.
Media Exposure and National Identity Formation among College Youth in Postcolonial Macau
Authors: WANG HONGYU
Published: April 2018

Using survey method, this study compares the relative importance of exposure to Chinese media, pro-China local media, pro-democracy local media, and new media (e.g., Weibo, Facebook) on the building of national identity among Macau college students. We argue that the effect of media exposure on national identity formation is not uniform, owing to the political leanings of the media and the platform on which the information is transmitted (new media vs. traditional media). We find that getting news about China on Facebook is the most important predictor of the formation of national identity among college youth in Macau, followed by getting news on Weibo and exposure to traditional Chinese media. Conversely, exposure to pro-democracy local media and frequent use of Facebook exert a negative effect on national identity building among college youth in Macau. Positive sentiment toward China and trust in the central government act as mediators and fully explain the relationship between exposure to traditional pro-China media and national identity but cannot explain the positive effect of exposure to new media on national identity formation.
Physical Generation of Tsunami Waves in Offshore Region
Authors: Wang Qian , Fang Yong-Liu , Liu Hua
Published: April 2018

This work describes a new physical wave-generation system, which is capable of generating the following waves in a wave flume: solitary waves, surge waves, and undular bores. The solitary waves are generated by a 2.4-m long stroke piston-type wavemaker using conventional methods. To generate surge waves, the system works with a reservoir built on one side of the wave flume. A high-power pump-pipe system with a pneumatic valve is used to connect the wave flume and the reservoir. The undular bores are generated by superimposing multiple solitary waves on the surge wave. This new wave generation system has gone through a careful calibration and the experimental data show good repeatability.
Existence and approximative fixed points for multifunctions
Authors: Afshari Hojjat , Aydi Hassen
Published: April 2018

The purpose of this paper is to present some new fixed point theorems for multifunctions, obtained by combining the methods of Suzuki and Samet and by using different conditions for generalized contractive multifunctions. Some examples are also considered.
An elementary proof of the symplectic spectral theorem
Authors: Malagón Camilo Sanabria
Published: April 2018

The classical spectral theorem completely describes self-adjoint operators on finite-dimensional inner product vector spaces as linear combinations of orthogonal projections onto pairwise orthogonal subspaces. We prove a similar theorem for self-adjoint operators on finite-dimensional symplectic vector spaces over perfect fields. We show that these operators decompose according to a polarization, i.e. as the product of an operator on a Lagrangian subspace and its dual on a complementary Lagrangian. Moreover, if all the eigenvalues of the operator are in the base field, then there exists a Darboux basis such that the matrix representation of the operator is [Formula: see text] blocks block-diagonal, where the first block is in Jordan normal form and the second block is the transpose of the first one.
Global solvability and regularity for ∂¯ on an annulus between two weakly convex domains which satisfy property (P)
Authors: Saber Sayed
Published: April 2018

Let [Formula: see text] be a complex manifold of dimension [Formula: see text] and let [Formula: see text]. Let [Formula: see text] be a weakly [Formula: see text]-convex and [Formula: see text] be a weakly [Formula: see text]-convex in [Formula: see text] with smooth boundaries such that [Formula: see text]. Assume that [Formula: see text] and [Formula: see text] satisfy property [Formula: see text]. Then the compactness estimate for [Formula: see text]-forms [Formula: see text] holds for the [Formula: see text]-Neumann problem on the annulus domain [Formula: see text]. Furthermore, if [Formula: see text] is [Formula: see text]-closed [Formula: see text]-form, which is [Formula: see text] on [Formula: see text] and which is cohomologous to zero on [Formula: see text], the canonical solution [Formula: see text] of the equation [Formula: see text] is smooth on [Formula: see text].
Orbital stability of standing waves for nonlinear fractional Schrödinger equation with unbounded potential
Authors: Liu Xiaohua
Published: April 2018

In this paper, the orbital stability of standing waves for nonlinear fractional Schrödinger equation is considered. By constructing the constrained functional extreme-value problem, the existence of standing waves is studied. With the help of the orbital stability theories presented by Grillakis, Shatah and Strauss, the orbital stability of standing waves is determined by the sign of a discriminant. To our knowledge, it is the first time that the abstract orbital stability theories presented by Grillakis, Shatah and Strauss are applied to study the stability of solutions for fractional evolution equation.