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      • SCOPUS

        The Role of Small and Medium Enterprises in Achieving Economic Goals of the Vision of Saudi Arabia 2030

        Mohammed Ali Mohamed Ahmed ALI(Mohammed Ali Mohamed Ahmed ALI ),Ahmed Saied Rahama ABDALLAH(Ahmed Saied Rahama ABDALLAH ),SalimAhmed Mohamed AlSHEHRI(SalimAhmed Mohamed AlSHEHRI ) 한국유통과학회 2023 The Journal of Asian Finance, Economics and Busine Vol.10 No.2

        This research aims to identify the role that small and medium enterprises (SMEs) can play in achieving the economic goals of the vision of Saudi Arabia 2030. The study relied on descriptive analysis, designing a standard model, and analyzing it using the Eviews9 program. The study also adopted the questionnaire as a tool for data collection. The study area covered Alkharj and Hawtat Bani Tamim governorates. The sample size of the study was 142 participants. The study’s results confirmed the existence of a significant impact of changes in independent variables (X1, X2, X3, X4), which are (GDP, non-oil exports, number of employees, and public revenues), respectively. The dependent variable (Y) represents the number of small and medium-sized businesses in the Kingdom of Saudi Arabia. Additionally, it was found that 61.3% of small and medium-sized enterprises in the governorates of Al-Kharj and Hawtat Bani Tamim operate in the commercial sector. Most study participants concur that SMEs significantly lowered the unemployment rate and helped boost the GDP rate in the Kingdom of Saudi Arabia. The obstacles and difficulties facing the establishment of these enterprises were financial problems, marketing problems, and corporate monopoly. Furthermore, most of the small and medium l enterprises faced financing problems.

      • Channel Clustering and QoS Level Identification Scheme for Multi-Channel Cognitive Radio Networks

        Ali, Amjad,Yaqoob, Ibrar,Ahmed, Ejaz,Imran, Muhammad,Kwak, Kyung Sup,Ahmad, Adnan,Hussain, Syed Asad,Ali, Zulfiqar IEEE 2018 IEEE communications magazine Vol.56 No.4

        <P>The increasing popularity of wireless services and devices necessitates high bandwidth requirements; however, spectrum resources are not only limited but also heavily underutilized. Multiple license channels that support the same levels of QoS are desirable to resolve the problems posed by the scarcity and inefficient use of spectrum resources in multi-channel cognitive radio networks (MCRNs). One reason is that multimedia services and applications have distinct, stringent QoS requirements. However, due to a lack of coordination between primary and secondary users, identifying the QoS levels supported over available licensed channels has proven to be problematic and has yet to be attempted. This article presents a novel Bayesian non-parametric channel clustering scheme, which identifies the QoS levels supported over available license channels. The proposed scheme employs the infinite Gaussian mixture model and collapsed Gibbs sampler to identify the QoS levels from the feature space of the bit rate, packet delivery ratio, and packet delay variation of licensed channels. Moreover, the real measurements of wireless data traces and comparisons with baseline clustering schemes are used to evaluate the performance of the proposed scheme.</P>

      • Endophytic bacterial diversity of <i>Avicennia marina</i> helps to confer resistance against salinity stress in <i>Solanum lycopersicum</i>

        Ali, Amjad,Shahzad, Raheem,Khan, Abdul Latif,Halo, Boshera A.,Al-Yahyai, Rashid,Al-Harrasi, Ahmed,Al-Rawahi, Ahmed,Lee, In-Jung Informa UK (TaylorFrancis) 2017 Journal of plant interactions Vol.12 No.1

        <P>The current study aimed to explore the endophytic bacterial diversity of Avicennia marina and the potential roles of these endophytes in counteracting saline conditions in tomato plants. Molecular analysis revealed strains from Paenibacillus, Bacillus, Microbacterium, Citrobacter, Lysinibacillus, Halomonas, Virgibacillus, Exiguobacterium, and Vibrio. However, Bacillus pumilus AM11 and Exiguobacterium sp. AM25 showed significantly higher growth in saline media. In response to salinity stress, tomato plants treated with AM11 and AM25 showed significantly higher (similar to 15-23%) biomass, photosynthetic rate and pigment accumulation compared to controls. Salinity-exposed plants had significantly reduced growth and increased (three-fold) lipid peroxidation, whilst glutathione, catalase, and peroxidase activities were significantly reduced. In contrast, AM11, AM25, and methionine improved these physiochemical attributes. The study concludes that the application of bacterial endophytes from plants growing in saline conditions can offer other plants similar stress-resistance potential. Such halophytic bacterial strains can be used to improve plant growth in saline conditions.</P>

      • Molecular determinants of ovarian cancer chemoresistance: new insights into an old conundrum

        Ali, Ahmed Y.,Farrand, Lee,Kim, Ji Young,Byun, Sanguine,Suh, Jeong‐,Yong,Lee, Hyong Joo,Tsang, Benjamin K. Blackwell Publishing Inc 2012 Annals of the New York Academy of Sciences Vol.1271 No.1

        <P>Ovarian cancer is the most lethal gynecological malignancy. Cisplatin and its derivatives are first-line chemotherapeutics, and their resistance is a major hurdle in successful ovarian cancer treatment. Understanding the molecular dysregulation underlying chemoresistance is important for enhancing therapeutic outcome. Here, we review two established pathways in cancer chemoresistance. p53 is a major tumor suppressor regulating proliferation and apoptosis, and its mutation is a frequent event in human malignancies. The PI3K/Akt axis is a key oncogenic pathway regulating survival and tumorigenesis by controlling several tumor suppressors, including p53. The interplay between these pathways is well established, although the oncogenic phosphatase PPM1D adds a new layer to this intricate relationship and provides new insights into the processes determining cell fate. Inhibition of the PI3K/Akt pathway by functional food compounds as an adjunct to chemotherapeutics may tip the balance in favor of apoptosis rather than survival, enhancing therapeutic efficacy, and reducing side effects.</P>

      • New approach to calculate Weibull parameters and comparison of wind potential of five cities of Pakistan

        Ahmed Ali Rajput,Muhammad Daniyal,Muhammad Mustaqeem Zahid,Hasan Nafees,Misha Shafi,Zaheer Uddin Techno-Press 2022 Advances in energy research Vol.8 No.2

        Wind energy can be utilized for the generation of electricity, due to significant wind potential at different parts of the world, some countries have already been generating of electricity through wind. Pakistan is still well behind and has not yet made any appreciable effort for the same. The objective of this work was to add some new strategies to calculate Weibull parameters and assess wind energy potential. A new approach calculates Weibull parameters; we also developed an alternate formula to calculate shape parameters instead of the gamma function. We obtained k (shape parameter) and c (scale parameter) for two-parameter Weibull distribution using five statistical methods for five different cities in Pakistan. Maximum likelihood method, Modified Maximum likelihood Method, Method of Moment, Energy Pattern Method, Empirical Method, and have been to calculate and differentiate the values of (shape parameter) k and (scale parameter) c. The performance of these five methods is estimated using the Goodness-of-Fit Test, including root mean square error, mean absolute bias error, mean absolute percentage error, and chi-square error. The daily 10-minute average values of wind speed data (obtained from energydata.info) of different cities of Pakistan for the year 2016 are used to estimate the Weibull parameters. The study finds that Hyderabad city has the largest wind potential than Karachi, Quetta, Lahore, and Peshawar. Hyderabad and Karachi are two possible sites where wind turbines can produce reasonable electricity.

      • KCI등재

        Silver and zinc oxide nanoparticles induce developmental and physiological changes in the larval and pupal stages of Spodoptera littoralis (Lepidoptera: Noctuidae)

        Ahmed M.A. Ibrahim,Ali M. Ali 한국응용곤충학회 2018 Journal of Asia-Pacific Entomology Vol.21 No.4

        The rapid growth of nanotechnology application in various fields of science led to need of understanding their possible effects on development and physiology of insects before using them as control agents. Instead of feeding on a toxic dose, the impact of silver nanoparticles (AgNPs, 50–60 nm) and zinc oxide nanoparticles (ZnONPs, 10–30 nm) was studied at a nonlethal concentration on the larval stages of Spodoptera littoralis. Late second instar larvae of S. littoralis were treated with water, 10 mg/mL AgNPs and ZnONPs dipped castor leaves for 6 days. Both nanoparticles treated leaves caused reduction in both larval weight gain and pupal weight than water dipped leaves while ZnONPs only caused extended larval period. ZnONPs increased total hemocyte, granular cell and plasmatocyte counts while AgNPs increased plasmatocytes only. ZnONPs decreased the levels of protein, lipids and carbohydrates than control and AgNPs treated larvae. On the contrary, ZnONPs induced significant increase in the activities of amylase, glucose 6 phosphate dehydrogenase (G6PD), lipase as well as two antioxidative enzymes, the catalase and superoxide dismutase. These results clearly show that ZnONPs ingestion interfere with the digestive and immunological physiology as well as the development of S. littoralis.

      • KCI등재

        Expression and characterization of a recombinant Drosophila tyramine-β-hydroxylase in silkworm infected with recombinant baculovirus

        Ahmed M.H. Ali,Jae Man Lee,Mayumi Yoshida,Kosuke Sakashita,Jumpei Torii,Takahiro Kusakabe,Akinori Hirashima 한국응용곤충학회 2012 Journal of Asia-Pacific Entomology Vol.15 No.4

        The insect nervous systemcontains biogenic amines such octopamine (OA),which is synthesized fromtyramine (TA) by catalysis of tyramine-β-hydroxylase (TβH). In this study, the Drosophila 70 kDa tyramine-β-hydroxylase (DmTβH) protein was purified after the recombinant nucleopolyhedrovirus isolated from Bombyx mori (BmNPV) containing the TβH gene was injected into the hemocoel of the fifth instar larvae from the d17B. mori strain. Western blot analysis revealed an immunoreactive band with a molecular mass of 70 kDa. The products formed by incubating the enzyme reaction mixture were separated and detected by reverse phase high-performance liquid chromatography. The optimum pH, temperature, and incubation time for the conversion of TA to OAwere 7.6, 25 °C, and 30 min, respectively. The inhibitory experiments using various concentrations of 1-(2-methoxy-5-methylphenyl) imidazole-2(3H)-thione (MMIT) showed that MMIT inhibited DmTβH dose-dependently and that this method can be applied for screening DmTβH inhibitors.

      • KCI등재

        Molecular cloning and characterization of a recombinant Bombyx mori tyramine-β-hydroxylase in a silkworm cell line using a baculovirus expression vector system

        Ahmed M.H. Ali,Nazmul Hasan,Renkai Guo,Hiroto Ohta,Akinori Hirashima 한국응용곤충학회 2014 Journal of Asia-Pacific Entomology Vol.17 No.3

        Octopamine (OA) and tyramine (TA) are biogenic amines that act as neurotransmitters, neurohormones, andneuromodulators in the invertebrate nervous system. Tyramine-β-hydroxylase (TβH) catalyzes the biosynthesisof OA from TA. In this study, cDNA encoding Bombyx mori TβH (BmTβH) was cloned from the brain of the silkwormB. mori. The BmTβH mRNA comprised 2204 nucleotide residues and contained an open reading frameencoding 592 amino acids. The deduced amino acid sequence shared homology to several proteins belongingto the insect TβH family. Functional expression of the cloned cDNA was obtained using a B. mori baculovirus expressionvector system. Western blot analysis revealed an immunoreactive band with a molecular mass of~67.4 kDa. Reverse-phase high-performance liquid chromatography (HPLC) was used to identify the productsformed during incubation of the enzyme reaction mixture. The optimumpH and temperature for the conversionof TA to OA were 7.5 and 25 °C, respectively. During incubation, the reaction was linear for the first 30 min at25 °C and pH 7.5. Inhibitory experiments carried out with various concentrations of an inhibitor showed thatthis method can be used for screening of BmTβH inhibitors.

      • KCI등재

        Association of Plasma Ghrelin Levels with Insulin Resistance in Type 2 Diabetes Mellitus among Saudi Subjects

        Ali Ahmed Al Qarni,Faris Elbahi Joatar,Nagalla Das,Mohamed Awad,Mona Eltayeb,Ahmed Gasim Al-Zubair,Muhalab E. Ali,Abdulaziz Al Masaud,Abdirashid M. Shire,Khalid Gumaa,Hayder A. Giha 대한내분비학회 2017 Endocrinology and metabolism Vol.32 No.2

        Background: Although the exact mechanism of insulin resistance (IR) has not yet been established, IR is the hallmark characteristic of type 2 diabetes mellitus (T2DM). The aim of this study was to examine the relationship between plasma ghrelin levels and IR in Saudi subjects with T2DM. Methods: Patients with T2DM (n=107, cases) and non-diabetic apparently healthy subjects (n=101, controls) from Saudi Arabia were included in this study. The biochemical profiles and plasma insulin levels of all subjects were analyzed, and IR was estimated using the homeostatic model assessment of insulin resistance (HOMA-IR) index. Active ghrelin levels in plasma were measured using the radioimmunoassay technique. Results: Only 46.7% (50 of 107) of the T2DM subjects had IR, including 26% (28 of 107) with severe IR (HOMA-IR ≥5), while 5.9% (six of 101) of the controls had moderate IR (3≤ HOMA-IR <5). HOMA-IR values were not associated with age, disease duration, or gender. Importantly, T2DM itself and the co-occurrence of IR with T2DM were significantly associated with low plasma ghrelin levels. However, ghrelin levels were inversely correlated with the HOMA-IR index, body weight, and fasting plasma insulin levels, mainly in the control subjects, which was indicative of the breakdown of metabolic homeostasis in T2DM. Conclusion: The prevalence of IR was relatively low, and IR may be inversely associated with plasma ghrelin levels among Saudi patients with T2DM.

      • KCI등재

        Synthesis and Three-dimensional Qualitative Structure Selectivity Relationship of 3,5- Disubstituted-2,4-Thiazolidinedione Derivatives As COX2 Inhibitors

        Ahmed M. Ali,Gamal E. Saber,Nadia M. Mahfouz,Mahmoud A. El-Gendy,Awwad A. Radwan,Mohamed A.-El. Hamid 대한약학회 2007 Archives of Pharmacal Research Vol.30 No.10

        In our effort for synthesis of selective COX2 inhibitors, certain new 2,4-thiazolidinedione derivatives were synthesized. It necessitates preparation of potassium salt of 2,4-thiazolidinedione 2, which condensed with intermediate 4a. The resulting 3-[2-(4-methylphenyl)-2-oxo-1-phenylethyl]- 2,4-thiazolidinedione 8 was condensed with appropriate aldehyde to afford compounds 10a, 10i-l, 10o and 10p. Compounds (9a-l, 10a-n, 10p, 11 and 12) were obtained through the preparation of 5-arylmethylidene-2,4-thiazolidinediones 6a-p and reaction of its potassium salt 7a-p with compounds 4a, 4b, and 5. Some compounds displayed significant analgesic activity as compared to reference standards. The anti-inflammatory activity of the synthesized compounds revealed that intermediate 8 and compounds 9c, 10c and 10d showed good results. Compound 10c produced no significant mucosal injury. HipHop methodology of Catalyst program was used to build up hypothetical model of selective COX2 inhibitors followed by fitting the synthesized compounds to this model. Compounds 10c and 10d were suspected to be promising selective COX2 inhibitors. Also, compounds (6c, 8, 9a,c,d,k, 10a,c,d,k, 11 and 12) were docked into COX1 and COX2 X-ray structures, using DOCK6 program. Docking results suggested that several of these derivatives are active COX inhibitors with a significant preference for COX2.

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