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Fulltext Landslide susceptibility mapping using averaged weightage score and GIS: a case study at Kuala Lumpur

Mahmud, A.R., Awad, A., Billa, R.

Pertanika Journal of Science & Technology, 2013;21(2):473-486.
MyJurnal

Many residential areas of Kuala Lumpur are susceptible to landslides; this is seen in the frequency of landslide occurences in these areas. The objective of this study is to delineate landslide risk areas in support of development planning, monitoring and control of unstable areas. In this study, five landslide causative factors were extracted from satellite imagery and maps provided by the Geological Survey Department of Malaysia. Factors included in the study including land use, river density and lineament derived from Landsat ETM image, precipitation amount from rain gauge stations and lithology, were extracted from the geological map of the study area. Layers were analyzed and divided into subclasses. An average weightage score was applied to calculate the subclasses into percentage weights of influence on landslide. Overlay, geo-processing and geo-statistic techniques in GIS were used to discriminate these weighted subclasses into landslide susceptibility at low, medium and high levels of risk areas. Results showed very high susceptible areas covering 0.21% of Kuala Lumpur of which 5.02% were found in the highly urbanized areas. Meanwhile, a landslide susceptibility map was generated to show low, medium and high susceptible areas in Kuala Lumpur. Results were verified using recorded cases of landslides in Kuala Lumpur which showed a 77% agreement with the study.
Fulltext The Role of Zinc Chloride in Enhancing Mechanical, Thermal and Electrical Performance of Ethylene Vinyl Acetate/Carbonized Wood Fiber Conductive Composite

Mohd Pisal MH, Osman AF, Jin TS, Rahman RA, Alrashdi AA, Masa A

Polymers (Basel), 2021 Feb 17;13(4).
PMID: 33671304 DOI: 10.3390/polym13040600

Carbonized natural filler can offer the production of low cost composites with an eco-friendliness value. The evolving field of electronics encourages the exploration of more functions and potential for carbonized natural filler, such as by modifying its surface chemistry. In this work, we have performed surface modification on carbonized wood fiber (CWF) prior to it being used as filler in the ethylene vinyl acetate (EVA) composite system. Zinc chloride (ZnCl2) with various contents (2 to 8 wt%) was used to surface modify the CWF and the effects of ZnCl2 composition on the surface morphology and chemistry of the CWF filler were investigated. Furthermore, the absorptive, mechanical, thermal, and electrical properties of the EVA composites containing CWF-ZnCl2 were also analyzed. SEM images indicated changes in the morphology of the CWF while FTIR analysis proved the presence of ZnCl2 functional groups in the CWF. EVA composites incorporating the CWF-ZnCl2 showed superior mechanical, thermal and electrical properties compared to the ones containing the CWF. The optimum content of ZnCl2 was found to be 6 wt%. Surface modification raised the electrical conductivity of the EVA/CWF composite through the development of conductive deposits in the porous structure of the CWF as a channel for ionic and electronic transfer between the CWF and EVA matrix.
Fulltext On the Use of OPEFB-Derived Microcrystalline Cellulose and Nano-Bentonite for Development of Thermoplastic Starch Hybrid Bio-Composites with Improved Performance

Lai DS, Osman AF, Adnan SA, Ibrahim I, Alrashdi AA, Ahmad Salimi MN, et al.

Polymers (Basel), 2021 Mar 15;13(6).
PMID: 33803984 DOI: 10.3390/polym13060897

Thermoplastic starch (TPS) hybrid bio-composite films containing microcrystalline cellulose (C) and nano-bentonite (B) as hybrid fillers were studied to replace the conventional non-degradable plastic in packaging applications. Raw oil palm empty fruit bunch (OPEFB) was subjected to chemical treatment and acid hydrolysis to obtain C filler. B filler was ultra-sonicated for better dispersion in the TPS films to improve the filler-matrix interactions. The morphology and structure of fillers were characterized by scanning electron microscope (SEM), Fourier transform infrared spectroscopy (FTIR) and X-ray diffraction (XRD). TPS hybrid bio-composite films were produced by the casting method with different ratios of B and C fillers. The best ratio of B/C was determined through the data of the tensile test. FTIR analysis proved the molecular interactions between the TPS and the hybrid fillers due to the presence of polar groups in their structure. XRD analysis confirmed the intercalation of the TPS chains between the B inter-platelets as a result of well-developed interactions between the TPS and hybrid fillers. SEM images suggested that more plastic deformation occurred in the fractured surface of the TPS hybrid bio-composite film due to the higher degree of stretching after being subjected to tensile loading. Overall, the results indicate that incorporating the hybrid B/C fillers could tremendously improve the mechanical properties of the films. The best ratio of B/C in the TPS was found to be 4:1, in which the tensile strength (8.52MPa), Young's modulus (42.0 MPa), elongation at break (116.4%) and tensile toughness of the film were increased by 92%, 146%, 156% and 338%, respectively. The significantly improved strength, modulus, flexibility and toughness of the film indicate the benefits of using the hybrid fillers, since these features are useful for the development of sustainable flexible packaging film.
Fulltext Awareness and Attitude Toward Epidural Analgesia During Labor Among Pregnant Women in Taif City: A Hospital-Based Study

Abdelhafeez AM, Alomari FK, Al Ghashmari HM, Newera A, Alshehri HO, Alzulfi FM, et al.

Cureus, 2023 Nov;15(11):e49367.
PMID: 38146556 DOI: 10.7759/cureus.49367

Objectives This study aimed to investigate the awareness and attitudes towards epidural analgesia (EA) among pregnant women in Taif City, Saudi Arabia. The rationale was to identify potential barriers to the acceptance and use of EA, which is an effective pain management option during labor. Methods We conducted a cross-sectional survey at a single healthcare center in Taif City. The participants, pregnant women visiting the center, were recruited using a convenience sampling method. Data collection was facilitated by a questionnaire distributed through a quick response (QR) code. The questionnaire assessed demographic information, awareness levels, previous exposure to EA, and personal attitudes toward its use during labor. Data analysis focused on quantifying the levels of awareness and identifying patterns in attitudes. Results The results revealed a low level of awareness about EA among the participants, with a significant proportion having never been exposed to it before the survey. Attitudes towards EA were varied, with some expressing openness to its use and others displaying apprehension or resistance, which appeared to be influenced by cultural perceptions and a lack of information. Conclusions The study highlighted a substantial lack of awareness and varied attitudes towards EA among pregnant women in Taif City. Educational interventions are necessary to increase awareness and address cultural misconceptions. The study's limited scope and potential sample bias suggest the need for broader culturally tailored research to inform strategies for improving the acceptance and utilization of labor analgesia.
Treg cell dysfunction and cutaneous exposure to S. aureus underlie eczema in DOCK8 deficiency

Wilkie H, Das M, Pelovitz T, Bainter W, Woods B, Alasharee M, et al.

J Allergy Clin Immunol, 2024 Jan 05.
PMID: 38185418 DOI: 10.1016/j.jaci.2023.12.020

BACKGROUND: DOCK8-deficient patients have severe eczema, elevated IgE and eosinophilia, features of Atopic Dermatitis (AD).
OBJECTIVE: To understand the mechanisms of eczema in DOCK8 deficiency.
METHODS: Skin biopsies were characterized for histology, immuno-fluorescence microscopy, and gene expression. Skin barrier function was measured by trans-epidermal water loss. Allergic skin inflammation was elicited in mice by epicutaneous (EC) sensitization with ovalbumin (OVA) or cutaneous application of S. aureus.
RESULTS: Skin lesions of DOCK8-deficient patients exhibited type-2 inflammation and the patients' skin was colonized by S. aureus, like in AD. Unlike in AD, DOCK8-deficient patients had a reduced FOXP3:CD4 ratio in their skin lesions, and their skin barrier function was intrinsically intact. Dock8-/- mice exhibited reduced numbers of cutaneous T regulatory cells (Tregs) and a normal skin barrier. Dock8-/- mice and mice with an inducible Dock8 deletion in Tregs exhibited increased allergic skin inflammation following EC sensitization with OVA. DOCK8 was shown to be important for Treg stability at sites of allergic inflammation and for the generation, survival, and suppressive activity of inducible Tregs (iTregs). Adoptive transfer of wild-type, but not DOCK8-deficient, OVA-specific iTregs suppressed allergic inflammation in OVA-sensitized skin of Dock8-/- mice. These mice developed severe allergic skin inflammation and elevated serum IgE levels following topical exposure to S. aureus. Both were attenuated following adoptive transfer of WT but not DOCK8 deficient Tregs CONCLUSION: Treg cell dysfunction increases susceptibility to allergic skin inflammation in DOCK8 deficiency and synergizes with cutaneous exposure to S. aureus to drive eczema in DOCK8 deficiency.
Study of B Meson Production in p+Pb Collisions at √[S(NN)]=5.02 TeV Using Exclusive Hadronic Decays

Khachatryan V, Sirunyan AM, Tumasyan A, Adam W, Asilar E, Bergauer T, et al.

Phys Rev Lett, 2016 Jan 22;116(3):032301.
PMID: 26849587 DOI: 10.1103/PhysRevLett.116.032301

The production cross sections of the B^{+}, B^{0}, and B_{s}^{0} mesons, and of their charge conjugates, are measured via exclusive hadronic decays in p+Pb collisions at the center-of-mass energy sqrt[s_{NN}]=5.02 TeV with the CMS detector at the CERN LHC. The data set used for this analysis corresponds to an integrated luminosity of 34.6 nb^{-1}. The production cross sections are measured in the transverse momentum range between 10 and 60 GeV/c. No significant modification is observed compared to proton-proton perturbative QCD calculations scaled by the number of incoherent nucleon-nucleon collisions. These results provide a baseline for the study of in-medium b quark energy loss in Pb+Pb collisions.
Fulltext Measurement of inclusive jet production and nuclear modifications in pPb collisions at [Formula: see text]

Khachatryan V, Sirunyan AM, Tumasyan A, Adam W, Asilar E, Bergauer T, et al.

Eur Phys J C Part Fields, 2016;76(7):372.
PMID: 28280445 DOI: 10.1140/epjc/s10052-016-4205-7

Inclusive jet production in pPb collisions at a nucleon-nucleon (NN) center-of-mass energy of [Formula: see text] is studied with the CMS detector at the LHC. A data sample corresponding to an integrated luminosity of 30.1 nb[Formula: see text] is analyzed. The jet transverse momentum spectra are studied in seven pseudorapidity intervals covering the range [Formula: see text] in the NN center-of-mass frame. The jet production yields at forward and backward pseudorapidity are compared and no significant asymmetry about [Formula: see text] is observed in the measured kinematic range. The measurements in the pPb system are compared to reference jet spectra obtained by extrapolation from previous measurements in pp collisions at [Formula: see text]. In all pseudorapidity ranges, nuclear modifications in inclusive jet production are found to be small, as predicted by next-to-leading order perturbative QCD calculations that incorporate nuclear effects in the parton distribution functions.
Measurement of differential cross sections for Higgs boson production in the diphoton decay channel in pp collisions at [Formula: see text]

Khachatryan V, Sirunyan AM, Tumasyan A, Adam W, Asilar E, Bergauer T, et al.

Eur Phys J C Part Fields, 2016 01 11;76:13.
PMID: 26855607

A measurement is presented of differential cross sections for Higgs boson (H) production in pp collisions at [Formula: see text][Formula: see text]. The analysis exploits the [Formula: see text] decay in data corresponding to an integrated luminosity of 19.7[Formula: see text] collected by the CMS experiment at the LHC. The cross section is measured as a function of the kinematic properties of the diphoton system and of the associated jets. Results corrected for detector effects are compared with predictions at next-to-leading order and next-to-next-to-leading order in perturbative quantum chromodynamics, as well as with predictions beyond the standard model. For isolated photons with pseudorapidities [Formula: see text], and with the photon of largest and next-to-largest transverse momentum ([Formula: see text]) divided by the diphoton mass [Formula: see text] satisfying the respective conditions of [Formula: see text] and [Formula: see text], the total fiducial cross section is [Formula: see text][Formula: see text].
Measurement of the [Formula: see text] production cross section in the all-jets final state in pp collisions at [Formula: see text][Formula: see text]

Khachatryan V, Sirunyan AM, Tumasyan A, Adam W, Asilar E, Bergauer T, et al.

Eur Phys J C Part Fields, 2016 03 08;76:128.
PMID: 27471431

The cross section for [Formula: see text] production in the all-jets final state is measured in pp collisions at a centre-of-mass energy of 8 [Formula: see text] at the LHC with the CMS detector, in data corresponding to an integrated luminosity of 18.4 [Formula: see text]. The inclusive cross section is found to be [Formula: see text] [Formula: see text]. The normalized differential cross sections are measured as a function of the top quark transverse momenta, [Formula: see text], and compared to predictions from quantum chromodynamics. The results are reported at detector, parton, and particle levels. In all cases, the measured top quark [Formula: see text] spectra are significantly softer than theoretical predictions.
Event generator tunes obtained from underlying event and multiparton scattering measurements

Khachatryan V, Sirunyan AM, Tumasyan A, Adam W, Asilar E, Bergauer T, et al.

Eur Phys J C Part Fields, 2016 03 17;76:155.
PMID: 27471433

New sets of parameters ("tunes") for the underlying-event (UE) modelling of the pythia8, pythia6 and herwig++ Monte Carlo event generators are constructed using different parton distribution functions. Combined fits to CMS UE proton-proton ([Formula: see text]) data at [Formula: see text] and to UE proton-antiproton ([Formula: see text]) data from the CDF experiment at lower [Formula: see text], are used to study the UE models and constrain their parameters, providing thereby improved predictions for proton-proton collisions at 13[Formula: see text]. In addition, it is investigated whether the values of the parameters obtained from fits to UE observables are consistent with the values determined from fitting observables sensitive to double-parton scattering processes. Finally, comparisons are presented of the UE tunes to "minimum bias" (MB) events, multijet, and Drell-Yan ([Formula: see text] lepton-antilepton+jets) observables at 7 and 8[Formula: see text], as well as predictions for MB and UE observables at 13[Formula: see text].
Fulltext Search for Dark Matter and Supersymmetry with a Compressed Mass Spectrum in the Vector Boson Fusion Topology in Proton-Proton Collisions at sqrt[s]=8 TeV

Khachatryan V, Sirunyan AM, Tumasyan A, Adam W, Asilar E, Bergauer T, et al.

Phys Rev Lett, 2017 Jan 13;118(2):021802.
PMID: 28128610 DOI: 10.1103/PhysRevLett.118.021802

A first search for pair production of dark matter candidates through vector boson fusion in proton-proton collisions at sqrt[s]=8 TeV is performed with the CMS detector. The vector boson fusion topology enhances missing transverse momentum, providing a way to probe supersymmetry, even in the case of a compressed mass spectrum. The data sample corresponds to an integrated luminosity of 18.5 fb^{-1}, recorded by the CMS experiment. The observed dijet mass spectrum is consistent with the standard model expectation. In an effective field theory, dark matter masses are explored as a function of contact interaction strength. The most stringent limit on bottom squark production with mass below 315 GeV is also reported, assuming a 5 GeV mass difference with respect to the lightest neutralino.
Fulltext Measurements of the [Formula: see text] production cross section in lepton+jets final states in pp collisions at 8 [Formula: see text] and ratio of 8 to 7 [Formula: see text] cross sections

Khachatryan V, Sirunyan AM, Tumasyan A, Adam W, Asilar E, Bergauer T, et al.

Eur Phys J C Part Fields, 2017;77(1):15.
PMID: 28260978 DOI: 10.1140/epjc/s10052-016-4504-z

A measurement of the top quark pair production ([Formula: see text]) cross section in proton-proton collisions at the centre-of-mass energy of 8[Formula: see text] is presented using data collected with the CMS detector at the LHC, corresponding to an integrated luminosity of 19.6[Formula: see text]. This analysis is performed in the [Formula: see text] decay channels with one isolated, high transverse momentum electron or muon and at least four jets, at least one of which is required to be identified as originating from hadronization of a b quark. The calibration of the jet energy scale and the efficiency of b jet identification are determined from data. The measured [Formula: see text] cross section is [Formula: see text]. This measurement is compared with an analysis of 7[Formula: see text] data, corresponding to an integrated luminosity of 5.0[Formula: see text], to determine the ratio of 8[Formula: see text] to 7[Formula: see text] cross sections, which is found to be [Formula: see text]. The measurements are in agreement with QCD predictions up to next-to-next-to-leading order.
Measurement of the [Formula: see text] cross section in pp collisions at [Formula: see text] TeVand limits on anomalous gauge couplings

Khachatryan V, Sirunyan AM, Tumasyan A, Adam W, Asilar E, Bergauer T, et al.

Eur Phys J C Part Fields, 2016;76(7):401.
PMID: 28286414 DOI: 10.1140/epjc/s10052-016-4219-1

A measurement of the W boson pair production cross section in proton-proton collisions at [Formula: see text] TeV is presented. The data collected with the CMS detector at the LHC correspond to an integrated luminosity of 19.4[Formula: see text]. The [Formula: see text] candidates are selected from events with two charged leptons, electrons or muons, and large missing transverse energy. The measured [Formula: see text] cross section is [Formula: see text], consistent with the standard model prediction. The [Formula: see text] cross sections are also measured in two different fiducial phase space regions. The normalized differential cross section is measured as a function of kinematic variables of the final-state charged leptons and compared with several perturbative QCD predictions. Limits on anomalous gauge couplings associated with dimension-six operators are also given in the framework of an effective field theory. The corresponding 95 % confidence level intervals are [Formula: see text], [Formula: see text], [Formula: see text], in the HISZ basis.

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