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排序方式: 共有113条查询结果,搜索用时 11 毫秒
81.
Joonyoung Lee Ki-Yoon Kim Yongchai Kwon Dahl-Young Khang 《Advanced functional materials》2024,34(1):2309386
Various sensors and electronic devices are recently developed to monitor human health in mechanically flexible or even stretchable forms for intimate contact with non-flat curvilinear surfaces of the human body. For successful operation of these devices, finding a proper way to electrically power them is very important. In this work, glucose/oxygen fueled enzymatic biofuel cells (EBFCs) based on microfluidic structured elastomeric polydimethylsiloxane substrate with wrinkled gold (Au) electrodes are suggested for power supply. For doing that, firstly, bottom surface of microfluidic channel is covered with buckled Au electrodes for stretchability. By microfluidic design showing capillary imbibition through fluidic channels, loading of catalyts is promoted. Interestingly, buckled Au electrodes induce much better anodic and cathodic reaction rates than those of non-buckled Au electrodes by 25% and 33%, respectively. This is because surface area and the amount of catalyst loading in electrodes increase by Au wrinkling. In evaluations of EBFCs using the buckled Au electrodes, maximum power density reaches 7.1 ± 0.64 µW cm−2, while they show decent performance of 5.4 ± 0.49 µW cm−2 even under external stretching. Taken together, it is corroborated that such proposed stretchable EBFCs are alternative for providing electrical power in wearable or implantable devices. 相似文献
82.
Nguyen Van Khang Nguyen Phong Dien Nguyen Thi Van Huong 《Archive of Applied Mechanics (Ingenieur Archiv)》2009,79(10):939-953
The main objective of the paper is to investigate the dynamic response of the prestressed beams on rigid supports to moving
concentrated loads. The governing equation of the transverse vibration of a prestressed continuous beam under the ununiformly
distributed load is analytically formulated, taking into account the effect of the prestressing. The forced transverse vibration
of the beam under the action of a large number of moving bodies has been investigated by using the method of substructures.
In addition, the reaction forces at every rigid supports can be determined from the obtained differential equations. A comparison
between the numerical results for the prestressed and the non-prestressed beam is presented to show the influence of the prestressing
and the moving velocity of the bodies on the dynamic response of the beam. The calculating results are also examined and validated
by experimental measurements at a large ferroconcrete bridge in Vietnam. 相似文献
83.
Lian Ee Khoo Ngoh Khang Goh Lip lin Koh Yan Xu Deborah J Whalen George Eng 《应用有机金属化学》1996,10(6):459-465
Four triphenyltin carboxylates formulated as o- Ph3SnOCOC6H4CH=N–Ar (Ar=C6H5; p -CH3C6H4; o -CH3C6H4; o -HOC6H4) were prepared and spectroscopically characterized. The crystal structure of o -Ph3SnOCOC6 H4CH=NC6H5 indicates that the tin atom, in each of the two molecules comprising the asymmetric unit, exists in a distorted tetrahedral geometry owing to an intramolecular acyl O. . .Sn contact. These new triphenyltin carboxylates display marked toxicity against the fungus Ceratocystis ulmi . 相似文献
84.
Faiza Naureen Yasar Shah Sayyed Ibrahim Shah Muhammad Abbas Inayat Ur Rehman Salar Muhammad Hamdullah Khang Wen Goh Fazli Khuda Amjad Khan Siok Yee Chan Mehwish Mushtaq Long Chiau Ming 《Molecules (Basel, Switzerland)》2022,27(13)
Mirtazapine is a tetracyclic anti-depressant with poor water solubility. The aim of this study was to improve the dissolution rate of mirtazapine by delivering the drug as a liquisolid compact. Central composite design (CCD) was employed for the preparation of mirtazapine liquisolid compacts. In this, the impacts of two independent factors, i.e., excipient ratio (carrier:coating) and different drug concentration on the response of liquisolid system were optimized. Liquisolid compacts were prepared using propylene glycol as a solvent, microcrystalline cellulose as a carrier, and silicon dioxide (Aerosil) as the coating material. The crystallinity of the formulated drug and the interactions between the excipients were examined using X-ray powder diffraction (XRD) and Fourier-transform infrared spectroscopy (FTIR), respectively. The dissolution study for the liquisolid compact was carried out as per FDA guidelines. The results showed loss of crystallinity of the mirtazapine in the formulation and was completely solubilized in non-volatile solvent and equally dispersed throughout the powder system. Moreover, drug dissolution was found to be higher in liquisolid compacts than the direct compressed conventional tablets (of mirtazapine). The liquisolid technique appears to be a promising approach for improving the dissolution of poorly soluble drugs like mirtazapine. 相似文献
85.
Emad M. Abdallah Abueliz Modwi Samiah H. Al-Mijalli Afrah E. Mohammed Hajo Idriss Abdulkader Shaikh Omar Mohamed Afifi Ammar AL-Farga Khang Wen Goh Long Chiau Ming 《Molecules (Basel, Switzerland)》2022,27(23)
In this work, ZnO, CrZnO, RuZnO, and BaZnO nanomaterials were synthesized and characterized in order to study their antibacterial activity. The agar well diffusion, minimum inhibitory concentration (MIC), and minimum bactericidal concentration (MBC) assays were used to determine the antibacterial activity of the fabricated nanomaterials against Staphylococcus aureus ATCC 29213, Escherichia coli ATCC35218, Klebsiella pneumoniae ATCC 7000603, and Pseudomonas aeruginosa ATCC 278533. The well-diffusion test revealed significant antibacterial activity against all investigated bacteria when compared to vancomycin at a concentration of 1 mg/mL. The most susceptible bacteria to BaZnO, RuZnO, and CrZnO were Staphylococcus aureus (15.5 ± 0.5 mm), Pseudomonas aeruginosa (19.2 ± 0.5 mm), and Pseudomonas aeruginosa (19.7 ± 0.5), respectively. The MIC values indicated that they were in the range of 0.02 to 0.2 mg/mL. The MBC values showed that the tested bacteria’s growth could be inhibited at concentrations ranging from 0.2 to 2.0 mg/mL. According to the MBC/MIC ratio, BaZnO, RuZnO, and CrZnO exhibit bacteriostatic effects and may target bacterial protein synthesis based on the results of the tolerance test. This study shows the efficacy of the above-mentioned nanoparticles on bacterial growth. Further biotechnological and toxicological studies on the nanoparticles fabricated here are recommended to benefit from these findings. 相似文献
86.
The Ramanujan Journal - This paper investigates the zero distribution of a sequence of polynomials $$left{ P_{m}(z)right} _{m=0}^{infty }$$ which satisfy a four-term recurrence whose... 相似文献
87.
Yik-Ling Chew Mei-Ann Khor Zhao Xu Sue-Kei Lee Jing-Wen Keng Sze-Huey Sang Gabriel Akyirem Akowuah Khang Wen Goh Kai Bin Liew Long Chiau Ming 《Molecules (Basel, Switzerland)》2022,27(17)
Traditional medicine is critical in disease treatment and management. Herbs are gaining popularity for disease management and treatment. Therefore, they can be utilised as complementary and alternative treatment (CAT) ingredients. Atopic dermatitis (AD) is one of the common non-communicable diseases. It is characterised by chronic inflammatory skin disease with intense pruritus and eczematous lesions. AD is associated with oxidative stress, microbial infection, and upregulation of inflammatory cytokines. Both children and adults could be affected by this skin disorder. The prevalence of AD is increasing along with the country’s level of development. This review revisited the literature on four medicinal herbs widely used as complementary medicine to manage AD. These therapeutic herbs are commonly eaten as food and used as spices in Asian cuisine. The four food herbs reviewed are Cassia alata, Coriandrum sativum, Curcuma longa Linn, and Azadirachta indica. Their traditional uses and phytochemical content will be covered. Four relevant pharmacological and biological activities of the plants crucial in AD management have been reviewed and discussed, including anti-inflammatory, anti-microbial, antioxidant, and wound recovery. 相似文献
88.
Jagjit Singh Dhaliwal Said Moshawih Khang Wen Goh Mei Jun Loy Md. Sanower Hossain Andi Hermansyah Vijay Kotra Nurolaini Kifli Hui Poh Goh Sachinjeet Kaur Sodhi Dhaliwal Hayati Yassin Long Chiau Ming 《Molecules (Basel, Switzerland)》2022,27(20)
Chalcones have been well examined in the extant literature and demonstrated antibacterial, antifungal, anti-inflammatory, and anticancer properties. A detailed evaluation of the purported health benefits of chalcone and its derivatives, including molecular mechanisms of pharmacological activities, can be further explored. Therefore, this review aimed to describe the main characteristics of chalcone and its derivatives, including their method synthesis and pharmacotherapeutics applications with molecular mechanisms. The presence of the reactive α,β-unsaturated system in the chalcone’s rings showed different potential pharmacological properties, including inhibitory activity on enzymes, anticancer, anti-inflammatory, antibacterial, antifungal, antimalarial, antiprotozoal, and anti-filarial activity. Changing the structure by adding substituent groups to the aromatic ring can increase potency, reduce toxicity, and broaden pharmacological action. This report also summarized the potential health benefits of chalcone derivatives, particularly antimicrobial activity. We found that several chalcone compounds can inhibit diverse targets of antibiotic-resistance development pathways; therefore, they overcome resistance, and bacteria become susceptible to antibacterial compounds. A few chalcone compounds were more active than conventional antibiotics, like vancomycin and tetracycline. On another note, a series of pyran-fused chalcones and trichalcones can block the NF-B signaling complement system implicated in inflammation, and several compounds demonstrated more potent lipoxygenase inhibition than NSAIDs, such as indomethacin. This report integrated discussion from the domains of medicinal chemistry, organic synthesis, and diverse pharmacological applications, particularly for the development of new anti-infective agents that could be a useful reference for pharmaceutical scientists. 相似文献
89.
Youssef Elouafy Adil El Yadini Hamza El Moudden Hicham Harhar Mohammed Merae Alshahrani Ahmed Abdullah Al Awadh Khang Wen Goh Long Chiau Ming Abdelhakim Bouyahya Mohamed Tabyaoui 《Molecules (Basel, Switzerland)》2022,27(22)
The present study investigated and compared the quality and chemical composition of Moroccan walnut (Juglans regia L.) oil. This study used three extraction techniques: cold pressing (CP), soxhlet extraction (SE), and ultrasonic extraction (UE). The findings showed that soxhlet extraction gave a significantly higher oil yield compared to the other techniques used in this work (65.10% with p < 0.05), while cold pressing and ultrasonic extraction gave similar yields: 54.51% and 56.66%, respectively (p > 0.05). Chemical composition analysis was carried out by GC–MS and allowed 11 compounds to be identified, of which the major compound was linoleic acid (C18:2), with a similar percentage (between 57.08% and 57.84%) for the three extractions (p > 0.05). Regarding the carotenoid pigment, the extraction technique significantly affected its content (p < 0.05) with values between 10.11 mg/kg and 14.83 mg/kg. The chlorophyll pigment presented a similar content in both oils extracted by SE and UE (p > 0.05), 0.20 mg/kg and 0.16 mg/kg, respectively, while the lowest content was recorded in the cold-pressed oil with 0.13 mg/kg. Moreover, the analysis of phytosterols in walnut oil revealed significantly different contents (p < 0.05) for the three extraction techniques (between 1168.55 mg/kg and 1306.03 mg/kg). In addition, the analyses of tocopherol composition revealed that γ-tocopherol represented the main tocopherol isomer in all studied oils and the CP technique provided the highest content of total tocopherol with 857.65 mg/kg, followed by SE and UE with contents of 454.97 mg/kg and 146.31 mg/kg, respectively, which were significantly different (p < 0.05). This study presents essential information for producers of nutritional oils and, in particular, walnut oil; this information helps to select the appropriate method to produce walnut oil with the targeted quality properties and chemical compositions for the desired purpose. It also helps to form a scientific basis for further research on this plant in order to provide a vision for the possibility of exploiting these oils in the pharmaceutical, cosmetic, and food fields. 相似文献
90.
Ilhame Bourais Salma Elmarrkechy Douae Taha Bouabid Badaoui Yassine Mourabit Najoua Salhi Mohammed Merae Alshahrani Ahmed Abdullah Al Awadh Abdelhakim Bouyahya Khang Wen Goh Ching Siang Tan Souad El Hajjaji Nadia Dakka Naima Iba 《Molecules (Basel, Switzerland)》2022,27(24)
Leaves, husk, kernels, and bark methanolic extracts of Juglans regia L. were tested for their in vitro antidiabetic, anti-inflammatory, and antioxidant activities. For these purposes, α-amylase and α-glucosidase were used as the main enzymes to evaluate antidiabetic activities. Moreover, lipoxidase and tyrosinase activities were tested to estimate anti-inflammatory properties. Antioxidant properties of Juglans regia L., extracts were determined using three different assays. Leaves extract has an important radical scavenging activity and a-amylase inhibition. Similarly, husk extracts showed high total phenolic content (306.36 ± 4.74 mg gallic acid equivalent/g dry extract) with an important α-amylase inhibition (IC50 = 75.42 ± 0.99 µg/mL). Kernels exhibit significant tyrosinase (IC50 = 51.38 ± 0.81 µg/mL) correlated with antioxidant activities (p < 0.05). Husk and bark extracts also showed strong anti-lipoxidase activities with IC50 equal to 29.48 ± 0.28 and 28.58 ± 0.35 µg/mL, respectively. HPLC-DAD-ESI-MS/MS analysis highlights the phenolic profile of methanolic extracts of Juglans regia L. plant parts. The identified polyphenols were known for their antioxidant, antidiabetic (dicaffeoyl-quinic acid glycoside in kernels), and anti-inflammatory (3,4-dihydroxybenzoic acid in leaves) activities. Further investigations are needed to determine molecular mechanisms involved in these effects as well as to study the properties of the main identified compounds. 相似文献