Allelopathic Potential of Adhatoda vasica NEES

Ayaz,Sajjida,Hussain, Farrukh,Ilahi, Ihsan,Kil, Bong-Seop 圓光大學校 基礎自然科學硏究所 1989 基礎科學硏究誌 Vol.8 No.3

파키스탄에 나는 Adhatoda vasica는 열대, 아열대성 관목으로 덤불을 이루고 있는데 그 주위에는 식물이 비교적 드물고 잘 자라지 못한다. 그래서 이 식물의 수용추출액, 빗물세탈액, 낙엽 낙지 및 임상토양을 써서 5종 실험 식물의 종자발아, 유식물 생장, 생체량, 수분과 엽록소 함량을 조사해 본 결과 상당히 억제됨을 알았다. 크로마토그래피 분석으로 caffeic acid등 5종의 화학물질을 확인했으며 이들은 A. vasica식물이 우점하며 그 주위 식물에 미치는 영향 즉 알에로패티작용에 일차적으로 관계가 있다고 본다. Adhatoda vasica Nees is a shrubby component of tropical and subtropical vegetation in Pakistan. It harbours relatively few unhealthy associated species in and around its thickets. Aqucous extracts, ram leachates, litter from shoots and soil underneath it invariably reduced germination, early growth, biomass, moisture and chlorophyll contents of Pemnisetum americanum, Setaria italica, Zea mays, Brassica campestris and Triticum vulgare in different laboratory experiments. Chromatographic analysis revealed the presence of caffeic, ferulic, vanillic, p-coumaric, p-OH-benzoic, and tannic acids in aqucous extracts. The phytotoxicity was related to the test species used, part assayed and parameter measured. It is suggested that the preclusion of the associated species and the dominance of A. vasica is primarily due to allelopathy. Negative grazing also provides better chances for its establishment.

Performance Evaluation of X-MAC/BEB Protocol for Wireless Sensor Networks

Ayaz Ullah,안종석 한국통신학회 2016 Journal of communications and networks Vol.18 No.5

This paper proposes an X-MAC/BEB protocol that runs abinary exponential backoff (BEB) algorithm on top of an X-MACprotocol to save more energy by reducing collision, especially indensely populated wireless sensor networks (WSNs). X-MAC, alightweight asynchronous duty cycle mediumaccess control (MAC)protocol, was introduced for spending less energy than its predeces-sor, B-MAC. One of X-MAC ’s conspicuous technique is a mech-anism to allow senders to promptly send their data when theirreceivers wake up. X-MAC, however, has no mechanism to dealwith sudden traffic fluctuations that often occur whenever closelylocated nodes simultaneously diffuse their sense data. To precisely evaluate the impact of the BEB algorithm on X-MAC, this paper builds an analytical model of X-MAC/BEB thatintegrates the BEB model with the X-MAC model. The analyticaland simulation results confirmed that X-MAC/BEB outperformedX-MAC in terms of throughput, delay, and energy consumption,especially in congested WSNs.

Numerical Analysis for Thermal Management of an Electric Vehicle Battery Module with the Nanofluid

Ayaz Hamza(아야즈 함자),Honghyun Cho(조홍현) 대한기계학회 2021 대한기계학회 춘추학술대회 Vol.2021 No.6

Thermal management system plays a key role in maintaining the temperature of the battery module in its optimal operating condition. Among different cooling strategies, the liquid cooling thermal management system is widely utilized due to its high energy density. Several factors affect the performance of the system like system design, mass flowrate, and different coolant. To find an optimal condition for the thermal management system, a three-dimensional rectangular cooling plate was designed and employed with base fluid and nanofluid to analyze its performance. The performance of this system was analyzed by two main factors were selected the battery maximum temperature and temperature difference along the battery module. The temperature difference along the module was 12°C for a time of 30 minutes.

Effect of plate size on meal energy intake in normal weight women

Ayaz, Aylin,Akyol, Asli,Cetin, Cansu,Besler, H. Tanju The Korean Nutrition Society 2016 Nutrition Research and Practice Vol.10 No.5

BACKGROUND/OBJECTIVES: Use of smaller plates to control food intake is a commonly recommended strategy for restricting energy intake, despite conflicting results. Therefore, the aim of this study was to examine whether or not three different sizes of plates influence energy intake during a multi-itemed buffet meal in normal weight women. SUBJECTS/METHODS: This was a cross-over study conducted on 37 female participants aged 19-25 years with normal BMI levels. Participants were recruited from Hacettepe University and the surrounding community. On experimental days, participants ate a standard breakfast and were then randomly assigned to eat lunch using a small (19 cm), medium (23 cm), or large (28 cm) diameter plate. Visual analogue scale (VAS) scores on sensory and satiety outcomes were measured for all meals. Energy and macronutrient intakes during lunch were recorded. RESULTS: There was no evidence that use of a smaller plate size reduced energy or specific macronutrient intake during the free choice lunch meal. Multiple visits to the serving table were not associated with energy or macronutrient intake. Plate size did not affect VAS scores during the test days. CONCLUSIONS: Plate size did not influence energy intake, meal composition, or palatability in normal weight women during a multi-itemed open buffet lunch. Studies in natural settings at the population level are needed to clarify current outcomes.

The effect of acrylamide incorporation on the thermal and physical properties of denture resins

Ayaz, Elif Aydogan,Durkan, Rukiye,Bagis, Bora The Korean Academy of Prosthodonitics 2013 The Journal of Advanced Prosthodontics Vol.5 No.2

PURPOSE. Polymethyl methacrylate (PMMA) is the most commonly used denture base material despite typically low in strength. The purpose of this study was to improve the physical properties of the PMMA based denture base resins (QC-20, Dentsply Ltd., Addlestone, UK; Stellon, AD International Ltd, Dentsply, Switzerland; Acron MC; GC Lab Technologies Inc., Alsip, Japan) by copolymerization mechanism. MATERIALS AND METHODS. Control group specimens were prepared according to the manufacturer recommendations. In the copolymer groups; resins were prepared with 5%, 10%, 15% and 20% acrylamide (AAm) (Merck, Hohenbrunn, Germany) content according to the moleculer weight ratio, respectively. Chemical structure was characterized by a Bruker Vertex-70 Fourier transform infrared spectroscopy (FTIR) (Bruker Optics Inc., Ettlingen, Germany). Hardness was determined using an universal hardness tester (Struers Duramin, Struers A/S, Ballerup, Denmark) equipped with a Vickers diamond penetrator. The glass transition temperature ($T_g$) of control and copolymers were evaluated by Perkin Elmer Diamond DSC (Perkin Elmer, Massachusetts,USA). Statistical analyses were carried out using the statistical package SPSS for Windows, version 15.0 (SPSS, Chicago, IL, USA). The results were tested regarding the normality of distribution with the Shapiro Wilk test. Data were analyzed using ANOVA with post-hoc Tukey test (P<.01). RESULTS. The copolymer synthesis was confirmed by FTIR spectroscopy. Glass transition temperature of the copolymer groups were higher than the control groups of the resins. The 10%, 15% and 20% copolymer groups of Stellon presented significantly higher than the control group in terms of hardness. 15% and 20% copolymer groups of Acron MC showed significantly higher hardness values when compared to the control group of the resin. Acrylamide addition did not affect the hardness of the QC-20 resin significantly. CONCLUSION. Within the limitation of this study, it can be concluded that copolymerization of PMMA with AAm increased the hardness value and glass transition temperature of PMMA denture base resins.

Multiview registration-based handheld 3D profiling system using visual navigation and structured light

Ayaz, Shirazi Muhammad,Kim, Min Young Informa UK (TaylorFrancis) 2017 International journal of optomechatronics Vol.11 No.1

<P>This article describes the 3D handheld profiling system composed of a stereo camera and an illumination projector to collect high-resolution data for close range of applications. Visual navigation approach is either based on feature matching or on accurate target, and the target-based approach was found to be more accurate if the 3D object has less texture on its surface. Block matching algorithm was used to render the single-view 3D reconstruction. For multiview 3D modeling, coarse registration and final refinement of the point clouds using iterative closest point algorithm were utilized. The proposed approach yields good accuracy for multiview registration as demonstrated in the results of this research.</P>

Gold Nanoparticles Conjugation Enhances Antiacanthamoebic Properties of Nystatin, Fluconazole and Amphotericin B

( Ayaz Anwar ),( Ruqaiyyah Siddiqui ),( Muhammad Raza Shah ),( Naveed Ahmed Khan ) 한국미생물 · 생명공학회 2019 Journal of microbiology and biotechnology Vol.29 No.1

Parasitic infections have remained a significant burden on human and animal health. In part, this is due to lack of clinically-approved, novel antimicrobials and a lack of interest by the pharmaceutical industry. An alternative approach is to modify existing clinically-approved drugs for efficient delivery formulations to ensure minimum inhibitory concentration is achieved at the target site. Nanotechnology offers the potential to enhance the therapeutic efficacy of drugs through modification of nanoparticles with ligands. Amphotericin B, nystatin, and fluconazole are clinically available drugs in the treatment of amoebal and fungal infections. These drugs were conjugated with gold nanoparticles. To characterize these goldconjugated drug, atomic force microscopy, ultraviolet-visible spectrophotometry and Fourier transform infrared spectroscopy were performed. These drugs and their gold nanoconjugates were examined for antimicrobial activity against the protist pathogen, Acanthamoeba castellanii of the T4 genotype. Moreover, host cell cytotoxicity assays were accomplished. Cytotoxicity of these drugs and drug-conjugated gold nanoparticles was also determined by lactate dehydrogenase assay. Gold nanoparticles conjugation resulted in enhanced bioactivity of all three drugs with amphotericin B producing the most significant effects against Acanthamoeba castellanii (p < 0.05). In contrast, bare gold nanoparticles did not exhibit antimicrobial potency. Furthermore, amoebae treated with drugs-conjugated gold nanoparticles showed reduced cytotoxicity against HeLa cells. In this report, we demonstrated the use of nanotechnology to modify existing clinically-approved drugs and enhance their efficacy against pathogenic amoebae. Given the lack of development of novel drugs, this is a viable approach in the treatment of neglected diseases.

Risk factors for intensive care unit admission and mortality in hospitalized COVID-19 patients

Ayaz Ahmed,Arshad Ainan,Malik Hajra,Ali Haris,Hussain Erfan,Jamil Bushra 대한중환자의학회 2020 Acute and Critical Care Vol.35 No.4

Background: This study investigated the clinical features and outcome of hospitalized coronavirus disease 2019 (COVID-19) patients admitted to our quaternary care hospital. Methods: In this retrospective cohort study, we included all adult patients with COVID-19 infection admitted to a quaternary care hospital in Pakistan from March 1 to April 15, 2020. The extracted variables included demographics, comorbidities, presenting symptoms, laboratory tests and radiological findings during admission. Outcome measures included in-hospital mortality and length of stay. Results: Sixty-six COVID-19 patients were hospitalized during the study period. Sixty-one percent were male and 39% female; mean age was 50.6±19.1 years. Fever and cough were the most common presenting symptoms. Serial chest X-rays showed bilateral pulmonary opacities in 33 (50%) patients. The overall mortality was 14% and mean length of stay was 8.4±8.9 days. Ten patients (15%) required intensive care unit (ICU) care during admission, of which six (9%) were intubated. Age ≥60 years, diabetes, ischemic heart disease, ICU admission, neutrophil to lymphocyte ratio ≥3.3, and international normalized ratio ≥1.2 were associated with increased risk of mortality. Conclusions: We found a mortality rate of 14% in hospitalized COVID-19 patients. COVID-19 cases are still increasing exponentially around the world and may overwhelm healthcare systems in many countries soon. Our findings can be used for early identification of patients who may require intensive care and aggressive management in order to improve outcomes.

Preparation of gold nanoparticles using Salicornia brachiata plant extract and evaluation of catalytic and antibacterial activity

Ayaz Ahmed, K.B.,Subramanian, S.,Sivasubramanian, A.,Veerappan, G.,Veerappan, A. Pergamon 2014 Spectrochimica acta. Part A, Molecular and biomole Vol.130 No.-

The current study deals with the synthesis of gold nanoparticles (AuNPs) using Salicornia brachiata (Sb) and evaluation of their antibacterial and catalytic activity. The SbAuNPs showed purple color with a characteristic surface plasmon resonance peak at 532nm. Scanning electron microscopy and transmission electron microscopy revealed polydispersed AuNPs with the size range from 22 to 35nm. Energy dispersive X-ray and thin layer X-ray diffraction analysis clearly shows that SbAuNPs was pure and crystalline in nature. As prepared gold nanoparticles was used as a catalyst for the sodium borohydride reduction of 4-nitro phenol to 4-amino phenol and methylene blue to leucomethylene blue. The green synthesized nanoparticles exhibited potent antibacterial activity against the pathogenic bacteria, as evidenced by their zone of inhibition. In addition, we showed that the SbAuNPs in combination with the regular antibiotic, ofloxacin, exhibit superior antibacterial activity than the individual.

Selection of Web Services by Using Diversified Service Rank

Ayaz Nazir Ahmed,Farooque Azam 보안공학연구지원센터 2014 International Journal of Software Engineering and Vol.8 No.4