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The effect of reactive plasticizer on viscoelastic and mechanical properties of solid rocket propellants based on different types of HTPB resin

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defence Technology（防务技术） 2024年第3期33卷 66-77页

作者： Tihomir Kovacevic Slavko Mijatov Jelena Grzetic Suzana Cakic Bojana Fidanovski Sasa Brzic Military Technical Institute Ministry of DefenceRatka Resanovica 1BelgradeSerbia Faculty of Technology University of NisBulevar osloboCenja 124LeskovacSerbia

Conventional plasticizers deteriorate mechanical and viscoelastic properties of the propellants due to their migration upon aging and long-term storage,which affects reliability and safety properties during *** address this issue,conventional plasticizer,dioctyl adipate(DOA),is replaced by reactive one,castor oil(CO).In addition,three different types of HTPB were used to obtain propellants with designed viscoelastic and mechanical *** CO increased propellants viscosity,without a significant impact on the propellant processability,regardless to the type of ***,mechanical properties were different depending on the type of resin,which were further analyzed by gel permeation chromatography(GPC).Addition of CO formed a denser polymer network and shifted T_(g) to higher values,compared to the compositions with *** tensile strength of CO-containing propellants was lower at +20℃ and +50℃ compared to the reference compositions,while the strain at maximum load and strain at break were significantly increased with pronounced plastic deformation,especially for samples at -30℃.The inclusion of CO in the propellants composition gives more room for adjusting a wide range of mechanical properties.

关键词： HTPB-based composite propellants Castor oil Reactive plasticizer Gel permeation chromatography Sol-gel analysis Mechanical and viscoelastic properties

Treatment of uveitis and scleritis patients in Malaysia

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International Journal of Ophthalmology(English edition) 2024年第3期17卷 518-527页

作者： Sieng Teng Seow Iqbal Tajunisah Fei Yee Lee Pooi Wah Lott Sagili Chandrasekhara Reddy Department of Ophthalmology University Malaya Eye Research Centre(UMERC)Faculty of MedicineUniversiti MalayaKuala Lumpur 59100Malaysia Clinical Research Centre Selayang HospitalMinistry of Health MalaysiaSelangor 68100Malaysia Department of Ophthalmology Faculty of Medicine and Defence HealthNational Defence University of MalaysiaKuala Lumpur 57000Malaysia

●AIM:To determine the common causes and visual outcome after treatment among uveitis and scleritis patients.●METHODS:This is a retrospective cohort observational *** consecutive clinical records of patients with newly diagnosed uveitis and scleritis over a 4-year period,from Jan.1,2017 to Dec.31,2020,were *** was collected at the presentation and included a follow-up period of one year.●RESULTS:A total of 288 patients were recruited during the study *** uveitis was the most common anatomical diagnosis(50.0%)followed by panuveitis(25.0%),scleritis(13.5%),posterior uveitis(6.9%),and intermediate uveitis(4.5%).Viral Herpes was the most common cause of infectious cases,while Vogt-Koyanagi-Harada(VKH)disease and human leucocyte antigen(HLA)B27 spondyloarthropathy were the leading causes of identifiable non-infectious *** of patients presented with unilateral,non-granulomatous uveitis with an absence of *** locations like posterior uveitis and panuveitis,and visual acuity worse than 3/60 at presentation were the factors associated with poor visual outcomes(P<0.05).About 60%of patients had an identifiable cause for the uveitis and scleritis,with nearly equal distribution of infectious(n=85,29.5%)and noninfectious causes(n=84,29.2%).About 14.5%of patients were clinically blind at 1y of *** most common complication in our uveitis patients was glaucoma(47.5%),followed by cystoid macula oedema(18.9%)and cataract(13.9%).●CONCLUSION:Uveitis and scleritis are important causes of ocular *** are potentially blinding diseases which can have a good outcome if diagnosed and treated early.

关键词： uveitis scleritis ocular morbidity blindness aetiology

Coumarin and eugenol ameliorate LPS-induced inflammation in RAW 264.7 cells via modulating the NLRP3 inflammasome pathway

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Asian Pacific Journal of Tropical Biomedicine 2024年第1期14卷 40-46页

作者： Jyotsana Bakshi Somnath Singh KP Mishra DRDO defence Institute of Physiology and Allied Sciences DelhiIndia

Objective:To investigate the underlying mechanism of anti-inflammatory action of coumarin and eugenol in lipopolysaccharide(LPS)-stimulated RAW 264.7 ***:RAW 264.7 cells were treated with 2.5μg/mL of LPS,50μM of coumarin,and 50μM eugenol for 24 *** viability of the cells was assessed using MTT *** production of nitric oxide was determined using Griess reagent and DCFH-DA was used to measure the production of reactive oxygen *** protein expression of NLRP3,IL-1β,NF-κB,and cyclooxygenase 2 was assessed using Western blot ***:Coumarin and eugenol showed anti-inflammatory effects against LPS-induced inflammatory response by ameliorating the expression of NLRP3 inflammasome and NF-κB,which further led to a subsequent reduction in IL-1β,nitric oxide,and reactive oxygen ***:Coumarin and eugenol exert their anti-inflammatory activities by modulating the NLRP3 inflammasome pathway and NF-κ*** compounds may have promising therapeutic applications for the treatment of various inflammatory diseases.

关键词： Inflammation Cytokines Coumarin Eugenol NLRP3 LPS

Redefining biofuels:Investigating oil palm biomass as a promising cellulose feedstock for nitrocellulose-based propellant production

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defence Technology（防务技术） 2024年第7期37卷 111-132页

作者： Khoirul Solehah binti Abdul Rahim Alinda binti Samsuri Siti Hasnawati binti Jamal Siti Aminah binti Mohd Nor Siti Nor Ain binti Rusly Hafizah binti Ariff Nur Shazwani binti Abdul Latif Centre for Tropicalization(CENTROP) Defence Research InstituteUniversiti Pertahanan Nasional MalaysiaKem Sungai Besi57000 Kuala LumpurMalaysia Department of Chemistry and Biology Centre for Defence Foundation StudiesUniversiti Pertahanan Nasional MalaysiaKem Sungai Besi57000 Kuala LumpurMalaysia

This review paper explores the potential of oil palm biomass as a valuable cellulose source for the production of nitrocellulose-based propellants,contributing to the green revolution and sustainable energy *** highlights the availability of the corresponding biomass in Malaysia and in line with global studies,the chemical compositions,as well as a brief description of current technologies for converting biomass of oil palm into value added products specifically *** to achieve maximum utilization of biomass from oil palm industry for cellulose production and prospective source for nitrocellulose-based propellant are also *** methodology section outlines the pretreatment of lignocellulosic fibres,cellulose extraction,and nitrocellulose production ***,the review underscores the prospective of palm oil biomass as a sustainable cellulose source for propellant manufacturing,while acknowledging the need for further research and advancements in the field.

关键词： Biopolymer Cellulose nitrate Energetic materials Green technology Palm oil

Velocity equation for grenades while impacting on dry sand media

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defence Technology（防务技术） 2024年第5期35卷 168-173页

作者： Martin Macko Xuan Son Bui Kongsathit Phanthavong Duc Hung Pham Van Gion Do Van Minh Do Jiri Skala University of defence BrnoCzech Republic Le Quy Don Technical University Ha NoiViet Nam

This paper deals with the collision of sphere shape grenades with sand *** central issue of the article is the establishing of an empirical velocity equation of the grenade while impacting on sand that is used to solve motion equations of the mechanical mechanism inside the impact grenade *** paper focuses on impact velocities that are lower than 5 m s^(-1).An experiment was conducted to study the velocity of the grenade while impacting on dry sand.A high-speed camera video was used to capture the grenade *** grenade velocity in the impact process was generated from these video *** types of fitting curves are used to regress the velocity equation of the grenade while interacting with the sand media and the best-fitting model is *** result shows the regression curve has a high correlation with the experiment data for grenade velocities below 5 m s^(-1).The received regression equation is useful for analyzing the working ability of the inertial mechanism inside the impact grenade or analyzing and choosing the appropriate parameters of each part in the inertial mechanism to meet the required characteristics of the mechanism.

关键词： Dynamic response Impact velocity Impact grenade Low-velocity impact

Parameter-Free Shifted Laplacian Reconstruction for Multiple Kernel Clustering

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IEEE/CAA Journal of Automatica Sinica 2024年第4期11卷 1072-1074页

作者： Xi Wu Zhenwen Ren F.Richard Yu the School of National defence Science and Technology Southwest University of Science and TechnologyMianyang 621010China the School of National defence Science and Technology Southwest University of Science and TechnologyMianyang 621010 the Guangxi Key Laboratory of Machine Vision and Intelligent Control Wuzhou UniversityWuzhou 543002 the Guangdong Laboratory of Artificial Intelligence and Digital Economy(SZ) Shenzhen 518060China

Dear Editor,This letter proposes a parameter-free multiple kernel clustering(MKC)method by using shifted Laplacian *** MKC can effectively cluster nonlinear data,but it faces two main challenges:1)As an unsupervised method,it is up against parameter problems which makes the parameters intractable to tune and is unfeasible in real-life applications;2)Only considers the clustering information,but ignores the interference of noise within Laplacian.

关键词： parameter letter Parameter

Neoadjuvant treatment of pancreatic ductal adenocarcinoma:Whom,when and how

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World Journal of Gastrointestinal Surgery 2024年第5期16卷 1223-1230页

作者： Nebojsa Manojlovic Goran Savic Stevan Manojlovic Clinic for Gastroenterology and Hepatology Military Medical AcademyFaculty of Medicine of the Military Medical AcademyUniversity of DefenceBelgrade 11000Serbia Military Medical Academy Faculty of Medicine of the Military Medical AcademyUniversity of DefenceBelgrade 11000Serbia Faculty of Medicine University of BelgradeBelgrade 11000Serbia

Pancreatic ductal adenocarcinoma(PDAC),which is notorious for its aggressiveness and poor prognosis,remains an area of great unmet medical need,with a 5-year survival rate of 10%-the lowest of all solid *** diagnosis,only 20%of patients have resectable pancreatic cancer(RPC)or borderline RPC(BRPC)disease,while 80%of patients have unresectable tumours that are locally advanced pancreatic cancer(LAPC)or have distant *** 60%of patients who undergo upfront surgery for RPC are unable to receive adequate adjuvant chemotherapy(CHT)because of postoperative complications and early cancer *** important paradigm shift to achieve better outcomes has been the sequence of therapy,with neoadjuvant CHT preceding *** surgical stages have emerged for the preoperative assessment of nonmetastatic pancreatic cancers:RPC,BRPC,and *** main goal of neoadjuvant treatment(NAT)is to improve postoperative outcomes through enhanced selection of candidates for curative-intent surgery by identifying patients with aggressive or metastatic disease during initial CHT,reducing tumour volume before surgery to improve the rate of margin-negative resection(R0 resection,a microscopic margin-negative resection),reducing the rate of positive lymph node occurrence at surgery,providing early treatment of occult micrometastatic disease,and assessing tumour chemosensitivity and tolerance to treatment as potential surgical *** this editorial,we summarize evidence concerning NAT of PDAC,providing insights into future practice and study *** research is needed to establish predictive biomarkers,measures of therapeutic response,and multidisciplinary stra tegies to improve patient-centered outcomes.

关键词： Pancreatic adenocarcinoma Neoadjuvant treatment Chemotherapy Upfront surgery Radiotherapy Response evaluation

Study of relationship between motion of mechanisms in gas operated weapon and its shock absorber

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defence Technology（防务技术） 2024年第3期33卷 42-54页

作者： Jiri Balla Roman Vitek Dung Nguyen Van Zbynek Krist Hung Nguyen Van Department of Weapons and Ammunition University of Defence BrnoCzech Republic Department of Weapons Le Quy Don Technical UniversityHanoiViet Nam Department of Design and Special Engineering Alexander Dubcek University of TrencinSlovakia

The article deals with the motion of the breech block carrier and the weapon casing of an automatic weapon mounted on a flexible carriage and the base of the *** works,which did not consider the dynamic properties of the base of the weapon,did not allow to reconcile the calculated and experimental results of the weapon casing displacement when shooting from firing *** the analysis of the motion of individual parts,the methods of mathematical modelling and firing experiments using a high-speed camera were *** show the best accord with experiment when modelling the system with 4 degrees of *** oscillation of the system regarding the movement of the breech block carrier and the weapon casing was investigated under changed conditions of rate of fire,the use of a muzzle brake and different types of shock *** velocities and displacements of the weapon casing and the breech block carrier at different values of the impulse of the gases to the breech block carrier were determined.

关键词： Shock absorber Gas-operated weapon Force-impulse diagram Recoil system Breech block carrier

Prolonged intermittent theta burst stimulation restores the balance between A_(2A)R-and A_(1)R-mediated adenosine signaling in the 6-hydroxidopamine model of Parkinson's disease

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Neural Regeneration Research 2025年第7期20卷 2053-2067页

作者： Milica Zeljkovic Jovanovic Jelena Stanojevic Ivana Stevanovic Milica Ninkovic Tihomir V.Ilic Nadezda Nedeljkovic Milorad Dragic Laboratory for Neurobiology Department of General Physiology and BiophysicsFaculty of BiologyUniversity of BelgradeBelgradeSerbia Medical Faculty of Military Medical Academy University of DefenceBelgradeSerbia

An imbalance in adenosine-mediated signaling,particularly the increased A_(2A)R-mediated signaling,plays a role in the pathogenesis of Parkinson's *** therapeutic approaches fail to alter disease progression,demonstrating the need for novel approaches in *** transcranial magnetic stimulation is a non-invasive approach that has been shown to improve motor and non-motor symptoms of Parkinson's ***,the underlying mechanisms of the beneficial effects of repetitive transcranial magnetic stimulation remain *** purpose of this study is to investigate the extent to which the beneficial effects of prolonged intermittent theta burst stimulation in the 6-hydroxydopamine model of experimental parkinsonism are based on modulation of adenosine-mediated *** with unilateral 6-hydroxydopamine lesions underwent intermittent theta burst stimulation for 3 weeks and were tested for motor skills using the Rotarod ***,quantitative reverse transcription polymerase chain reaction,immunohistochemistry,and biochemical analysis of components of adenosine-mediated signaling were performed on the synaptosomal fraction of the lesioned caudate *** intermittent theta burst stimulation improved motor symptoms in 6-hydroxydopamine-lesioned animals.A 6-hydroxydopamine lesion resulted in progressive loss of dopaminergic neurons in the caudate *** with intermittent theta burst stimulation began 7 days after the lesion,coinciding with the onset of motor *** treatment with prolonged intermittent theta burst stimulation,complete motor recovery was *** improvement was accompanied by downregulation of the e N/CD73-A_(2A)R pathway and a return to physiological levels of A_(1)R-adenosine deaminase 1 after 3 weeks of intermittent theta burst *** results demonstrated that 6-hydroxydopamine-induced degeneration reduced the expression of A_(1)R and elevated the expression of A_(2A)***

关键词： A_(1)R A_(2A)R adenosine receptors adenosine ecto-5′-nucleotidase intermittent theta burst stimulation non-invasive brain stimulation Parkinson's disease purinergic signalling