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Modelling the effect of non-pharmaceutical interventions on COVID-19 transmission from mobility maps

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Infectious Disease Modelling 2022年第3期7卷 400-418页

作者： Umair Hasan hamad al Jassmi Abdessamad Tridane Anderson Stanciole Farida.al-Hosani Bashir Aden Emirates Centre for Mobility Research United Arab Emirates UniversityAl Ain15551United Arab Emirates Department of Civil and Environmental Engineering United Arab Emirates UniversityAl Ain15551United Arab Emirates Mathematical Sciences Department College of ScienceUnited Arab Emirates UniversityAl Ain15551United Arab Emirates Department of Health Abu DhabiUnited Arab Emirates Abu Dhabi Public Health Center Abu DhabiUnited Arab Emirates

The world has faced the COVID-19 pandemic for over two years now,and it is time to revisit the lessons learned from lockdown measures for theoretical and practical epidemiological *** interlink between these measures and the resulting change in mobility(a predictor of the disease transmission contact rate)is *** thus propose a new method for assessing the efficacy of various non-pharmaceutical interventions(NPI)and examine the aptness of incorporating mobility data for epidemiological *** mobility maps for the United Arab Emirates are used as input datasets from the first infection in the country to mid-Oct *** was limited to the pre-vaccination period as this paper focuses on assessing the different NPIs at an early epidemic stage when no vaccines are available and NPIs are the only way to reduce the reproduction number(R_(0)).We developed a travel network density parameterβ_(t)to provide an estimate of NPI impact on mobility *** the infection-fa.ality ratio and time lag(onset-to-death),a Bayesian probabilistic model is adapted to calculate the change in epidemic development withβ*** showed that the change inβ_(t)clearly impacted R_(0).The three lockdowns strongly affected the growth of transmission rate and collectively reduced R_(0)by 78%before the restrictions were *** model forecasted daily infections and deaths by 2%and 3%fractional *** also projected what-if scenarios for different implementation protocols of each *** developed model can be applied to identify the most efficient NPIs for confronting new COVID-19 waves and the spread of variants,as well as for future pandemics.

关键词： Non-pharmaceutical interventions COVID-19 Epidemiological modelling Mobility maps

Magnetoelectric effect in multiferroic NdMn2O5

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Chinese Physics B 2017年第1期26卷 526-529页

作者： Syed hamad Bukhari Javed Ahmad Department of Physics Bahauddin Zakariya University Multan 60800 Pakistan

We have measured the dielectric constant for NdMn2O5 in an external magnetic field to map out the magnetoelectric phase diagram. The phase diagram corresponds well with the previously reported data of neutron diffraction and magnetic susceptibility. Our main finding is the observation of a dielectric anomaly in the low temperature phase with a strong magnetoelectric effect, which is attributed to the independent Nd^3＋ ordering. Moreover, the absence of the dielectric anomaly in the paramagnetic phase is discussed, keeping in view the exchange interaction and its dependence on the rareearth R^3＋ ionic radius.

关键词： sol–gel synthesis dielectric constant magnetoelectric effect phase transition

Thermo-Mechanical Simulation of Self-Heating of a High-Power Diode Made of Ti_(3)SiC_(2)(MAX) Phase-on-4H-SiC Substrate

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Journal of Thermal Science 2021年第3期30卷 939-949页

作者： ABOU hamad Valdemar SOUEIDAN Maher hamad Hassan GREMILLARD Laurent FABREGUE Damien ZGHEIB Charbel ZAATAR Youssef LPA Lebanese UniversityFaculty of ScienceJdeidetBP 90656Lebanon MATEIS UMR 5510Universitéde LyonINSA-Lyon20 Avenue Albert EinsteinF-69621 VilleurbanneFrance Lebanese National Council for Scientific Research Lebanese Atomic Energy CommissionRiad El Solh 11072260 BeirutLebanon Lebanese University Faculty of Engineering IIIRafic Hariri University CampusHadathLebanon Department of Physics and Astronomy(DPA) Faculty of Natural Sciences and applied SciencesNotre Dame University-LouaizeLebanon

The fact that traditional semiconductors have almost reached their performance limits in high power applications,is leading to failure in high power *** failure results from self-heating effects,leading to higher temperature and a breakdown of the electrical *** good thermal and mechanical properties of 4 H-SiC and Ti_(3)SiC_(2) and their good performance at high temperatures make them good candidates for high power *** order to improve the performance of electrical contacts,a thermo-mechanical simulation was carried out using the finite element method to study the self-heating effects in a high power PN diode made of a 4 H-SiC substrate with a Ti_(3)SiC_(2) electrical contact and al_(3)Ti *** three-dimensional model took into account the temperature dependency of several thermal and mechanical properties of the different materials to improve calculation *** simulate the self-heating,the power loss in the diode was calculated from the corresponding direct I-V *** addition,the interfacial thermal resistances(ITR)between the different layers were varied and studied in the thermo-mechanical investigation,in sequence to determine their effects on the heat dissipation and the resulting stresses in the *** results show that for realistic ITR values,the ITR barely affects heat diffusion mechanical stresses of the ***,ITR may cause serious problem to the functionality and the efficiency of some electronic *** the other hand,extremely large ITR leads to a decrease in the thermal stress in the *** control on the ITR may help to improve the performance of high-power devices in the future,in addition to providing more efficient electrical contacts.

关键词： thermo-mechanical simulation self-heating 4H-SiC MAX Phase electrical contact

Meteorological drought in semi-arid regions:A case study of Iran

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Journal of Arid Land 2022年第11期14卷 1212-1233页

作者： Hushiar HAMARASH Rahel hamad Azad RASUL Scientific Research Center Soran UniversitySoran 44008Iraq Faculty of Arts Department of GeographySoran UniversitySoran 44008Iraq

Drought occurs in almost all climate zones and is characterized by prolonged water deficiency due to unbalanced demand and supply of water,persistent insufficient precipitation,lack of moisture,and high *** caused by insufficient precipitation is a temporary and recurring meteorological *** in semi-arid regions is different from that in other regions,ranging from 50 to 750 *** general,the semi-arid regions in the west and north of Iran received more precipitation than those in the east and *** Terrestrial Climate(TerraClimate)data,including monthly precipitation,minimum temperature,maximum temperature,potential evapotranspiration,and the Palmer Drought Severity Index(PDSI)developed by the University of Idaho,were used in this *** PDSI data was directly obtained from the Google Earth Engine *** Standardized Precipitation Index(SPI)and the Standardized Precipitation Evapotranspiration Index(SPEI)on two different scales were calculated in time series and also both SPI and SPEI were shown in spatial distribution *** result showed that normal conditions were a common occurrence in the semi-arid regions of Iran over the majority of years from 2000 to 2020,according to a spatiotemporal study of the SPI at 3-month and 12-month time scales as well as the SPEI at 3-month and 12-month time ***,the PDSI detected extreme dry years during 2000-2003 and in 2007,2014,and *** many semi-arid regions of Iran,the SPI at 3-month time scale is higher than the SPEI at 3-month time scale in 2000,2008,2014,2015,and *** general,this study concluded that the semi-arid regions underwent normal weather conditions from 2000 to *** a way,moderate,severe,and extreme dry occurred with a lesser percentage,gradually *** to the PDSI,during 2000-2003 and 2007-2014,extreme dry struck practically all hot semi-arid regions of *** parts of the cold semi-arid regions,on the other hand,only ex

关键词： meteorological drought precipitation Standardized Precipitation Index Standardized Precipitation Evapotranspiration Index Palmer Drought Severity Index Iran

Topographic characteristics of keratoconus among a sample of Jordanian patients

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International Journal of Ophthalmology(English edition) 2014年第4期7卷 714-719页

作者： Mohammed ali Abu Ameerh Nathalie Bussières Ghada Ismail hamad Muawyah Dawoud al Bdour The University of Jordan Faculty of Applied Medical Sciences German Jordanian University

· AIM: To identify topographic characteristics of keratoconus in a Jordanian sample.· METHODS: This study characterized 210 corneas affected with keratoconus presenting to Jordan University Hospital. Patients were diagnosed based on clinical examinations and Pentacam imaging. Eyes of males(n =101) were of a similar proportion to females(n =109). all of the 111 patients were affected *** ranged between 13 and 44 y with a mean age of25.2y.· RESULTS: Results revealed significant differences between males and females at the level of the flat curvature power, basement membrane thickness and size of the anterior chamber. Eyes were arranged in three groups based on severity levels: mild, moderate and severe determined by the mean curvature power(Km).Results show that the flat(K1) and steep(K2) curvature powers, corneal asphericity coefficient(QV), thinnest point, pachy apex and basement membrane thickness are significantly different among the three groups, but not the corneal and anterior chamber *** a.alyses, based on sagittal maps, show no differences in keratometric values between eyes with different sagittal patterns except for the vertical location of the pachy apex relative to the pupil center and the thinnest point. Eyes with the island front elevation map are significantly more affected than eyes with the U shape and the ridge pattern.· CONCLUSION: all keratometric values measured except for corneal and anterior chamber volumes vary significantly with disease severity. The vertical pachy apex location correlates well with severity levels while the horizontal location seems to have no effect. Ourstudy also indicates that front elevation maps may be a better predictor of the severity of keratoconus than sagittal maps.

关键词： keratoconus morphology of keratoconus topographic characteristics

Brittle and ductile characteristics of intermetallic compounds in magnesium alloys: A large-scale screening guided by machine learning

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Journal of Magnesium and alloys 2023年第1期11卷 392-404页

作者： Russlan Jaafreh Yoo Seong Kang Kotiba hamad School of Advanced Materials Science&Engineering Sungkyunkwan UniversitySuwon 16419South Korea School of Applied Data Science Sungkyunkwan UniversitySuwon 16419South Korea

In the present work,we have employed machine learning(ML)techniques to evaluate ductile-brittle(DB)behaviors in intermetallic compounds(IMCs)which can form magnesium(Mg)*** procedure was mainly conducted by a proxy-based method,where the ratio of shear(G)/bulk(B)moduli was used as a proxy to identify whether the compound is ductile or *** from compounds information(composition and crystal structure)and their moduli,as found in open databases(AFLOW),ML-based models were built,and those models were used to predict the moduli in other compounds,and accordingly,to foresee the ductile-brittle behaviors of these new *** results reached in the present work showed that the built models can effectively catch the elastic moduli of new *** was confirmed through moduli calculations done by density functional theory(DFT)on some compounds,where the DFT calculations were consistent with the ML prediction.A further confirmation on the reliability of the built ML models was considered through relating between the DB behavior in MgBe_(13) and MgPd_(2),as evaluated by the ML-predicted moduli,and the nature of chemical bonding in these two compounds,which in turn,was investigated by the charge density distribution(CDD)and electron localization function(ELF)obtained by DFT *** ML-evaluated DB behaviors of the two compounds was also consistent with the DFT calculations of CDD and *** findings and confirmations gave legitimacy to the built model to be employed in further prediction ***,as examples,the DB characteristics were investigated in IMCs that might from in three Mg alloy series,involving AZ,ZX and WE.

关键词： Mg alloys Intermetallic compounds Ductile-brittle Machine learning algorithm Features DFT

Investigating materials and orientation parameters for the creation of a 3D musculoskeletal interface co-culture model

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Regenerative Biomaterials 2020年第4期7卷 413-425页

作者： hamad alsaykhan Jennifer Z.Paxton Anatomy@Edinburgh Edinburgh Medical School:Biomedical SciencesThe University of EdinburghTeviot PlaceEdinburgh EH89AGUK Department of Basic Medical Sciences College of Medicine and Health SciencesQassim UniversityPO Box 99151911 Unaizah CampusAl-Qassim 51911Saudi Arabia

Musculoskeletal tissue interfaces are a common site of injury in the young,active *** particular,the interface between the musculoskeletal tissues of tendon and bone is often injured and to date,no single treatment has been able to restore the form and function of damaged tissue at the bone-tendon *** engineering and regeneration hold great promise for the manufacture of bespoke in vitro models or implants to be used to advance repair and so this study investigated the material,orientation and culture choices for manufacturing a reproducible 3D model of a musculoskeletal interface between tendon and bone cell *** models are essential for future studies focussing on the regeneration of musculoskeletal interfaces in ***-encapsulated fibrin hydrogels,arranged in a horizontal orientation though a simple moulding procedure,were shown to best support cellular growth and migration of cells to form an in vitro tendon-bone *** study highlights the importance of acknowledging the material and technical challenges in establishing co-cultures and suggests a reproducible methodology to form 3D co-cultures between tendon and bone,or other musculoskeletal cell types,in vitro.

关键词： tendon bone 3D co-culture hydrogels musculoskeletal interface

Sodium-glucose co-transporter 2 inhibitors induced euglycemic diabetic ketoacidosis within four days of initiation

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World Journal of Diabetes 2022年第3期13卷 272-274页

作者： almurtada Razok Fateen Ata Sara Mohamed Ibrahim Ahmed Dabia hamad S H al Mohanadi Department of Internal Medicine Hamad Medical CorporationDoha 3050Qatar Department of Endocrinology Hamad Medical CorporationDoha 3050Qatar

Euglycemic diabetic ketoacidosis(EDKA)is a well-known complication of sodium-glucose co-transporter 2 inhibitors,and many cases with variable onset following the initiation of these agents are reported before,with a median onset of approximately 2 *** letter discusses a 45-year-old lady who initially presented with ischemic stroke but developed EDKA 4 d after starting empagliflozin,a rare *** patient had severe metabolic acidosis that necessitated admission into the intensive care *** discontinuation of empagliflozin and DKA management resulted in clinical recovery.

关键词： Euglycemic diabetic ketoacidosis Sodium-glucose co-transporter 2 inhibitors Type 2 diabetes mellitus Empagliflozin

Improved Multi-party Quantum Key Agreement with Four-qubit Cluster States

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Computers, Materials & Continua 2022年第10期73卷 225-232页

作者： Hussein Abulkasim Eatedal alabdulkreem Safwat hamad Faculty of Science New Valley UniversityEl-Kharga&the Academy of Scientific Research and TechnologyCairoEgypt College of Computer and Information Sciences Princess Nourah bint Abdulrahman UniversityRiyadhSaudi Arabia Faculty of Computer and Information Sciences Ain Shams UniversityCairoEgypt

Quantum key agreement is a promising key establishing protocol that can play a significant role in securing 5G/6G communication ***,Liu et al.(Quantum Information Processing 18(8):1-10,2019)proposed a multi-party quantum key agreement protocol based on four-qubit cluster states was *** aim of their protocol is to agree on a shared secret key among multiple remote *** et *** four-qubit cluster states to be the quantum resources and the X operation to securely share a secret *** addition,Liu et al.’s protocol guarantees that each participant makes an equal contribution to the final *** authors also claimed that the proposed protocol is secure against participant attack and dishonest participants cannot generate the final shared key ***,we show here that Liu et *** is insecure against a collusive attack,where dishonest participants can retrieve the private inputs of a trustworthy participant without being ***,the corresponding modifications are presented to address these security flaws in Liu et al.’s protocol.

关键词： Quantum key agreement 5G/6G communication networks collusive attacks quantum cryptography