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51.
Bayesian networks (BNs) are a useful tool for applications where dynamic decision-making is involved. However, it is not easy to learn the structure and conditional probability tables of BNs from small datasets. There are many algorithms and heuristics for learning BNs from sparse datasets, but most of these are not concerned with the quality of the learned network in the context of a specific application. In this research, we develop a new heuristic on how to build BNs from sparse datasets in the context of its performance in a real-time recommendation system. This new heuristic is demonstrated using a market basket dataset and a real-time recommendation model where all items in the grocery store are RFID tagged and the carts are equipped with an RFID scanner. With this recommendation model, retailers are able to do real-time recommendations to customers based on the products placed in cart during a shopping event. 相似文献
52.
An electrochemical drug‐DNA biosensor was developed for the detection of interaction between the anti‐cancer drug, Temozolomide (TMZ), and DNA sequences by using Differential Pulse Voltammetry at the graphite electrode surfaces. TMZ is a pro‐drug and an alkylating agent that crosses the blood‐brain barrier, so it is mainly used for brain cancers treatment. In this study, we aim to develop a‐proof‐of‐concept study to investigate the effect of TMZ on formerly methylated DNA sequences since TMZ shows its anti‐cancer activity by methylating the DNA. Interaction between TMZ and DNA causes localized distortion of DNA away from an idealized B‐form, resulting in a wider major groove and greater steric accessibility of functional groups in the base of the groove. According to the results, TMZ behaves as a ‘hybridization indicator’ because of its different electrochemical behavior to different strands of DNA. After interaction with TMZ, hybrid (double stranded DNA‐dsDNA) signals decreased dramatically whereas probe (single stranded DNA‐ssDNA) and control signals remain almost unchanged. The signal differences enabled us to distinguish ssDNA and dsDNA without using a label or tag. It is the first study to demonstrate the interaction between the TMZ and dsDNA created from probe and target. We use specific oligonucleotides sequences instead of using long dsDNA sequences. 相似文献
53.
Yusuf Nur Seda Yurteri Ioan Cianga Yusuf Yagci Jale Hacaloglu 《Journal of Analytical and Applied Pyrolysis》2007,80(2):453-459
Thermal degradation characteristic of polyphenylenes is an important issue for developing a rational technology of polymer processing and applications. In this study, we discussed thermal degradation of polyphenylenes (PP) with poly(-caprolactone) (PCL) and/or PCL/polystyrene copolymers (PSt) prepared by combined controlled polymerization and cross-coupling processes via direct pyrolysis mass spectrometry. When PP-graft-PCL/PSt copolymers were considered, thermally less stabile PCL side chains decomposed in the first step. In the second stage of pyrolysis, the decomposition of the polystyrene chains has taken place. A slight increase in thermal stability of PCL chains for PP-graft-PCL/PSt copolymers was noted compared to copolymer PP-graft-PCL due to the interaction between PSt and PCL chains. This interaction was stronger when PSt chains were linked to the 2-position of the 1,4-phenylene ring. 相似文献
54.
Eka Sunarwidhi Prasedya Nur Ardiana Hasriaton Padmi Bq Tri Khairina Ilhami Ni Wayan Riyani Martyasari Anggit Listyacahyani Sunarwidhi Aluh Nikmatullah Sri Widyastuti Haji Sunarpi Andri Frediansyah 《Molecules (Basel, Switzerland)》2021,26(21)
The red macroalga Gelidium latifolium is widely distributed in the coastal areas of Indonesia. However, current knowledge on its potential biological activities is still limited. In this study, we investigated the potential bioactive compounds in Gelidium latifolium ethanol extract (GLE), and its cytotoxic effects against the murine B16-F10 melanoma cell line. GLE shows high total phenolic content (107.06 ± 17.42 mg GAE/g) and total flavonoid content (151.77 ± 3.45 mg QE/g), which potentially contribute to its potential antioxidant activity (DPPH = 650.42 ± 2.01 µg/mL; ABTS = 557.01 ± 1.94 µg/mL). ESI-HR-TOF-MS analysis revealed large absorption in the [M-H]- of 327.2339 m/z, corresponding to the monoisotopic molecular mass of brassicolene. The presence of this compound potentially contributes to GLE’s cytotoxic activity (IC50 = 84.29 ± 1.93 µg/mL). Furthermore, GLE significantly increased the number of apoptotic cells (66.83 ± 3.06%) compared to controls (18.83 ± 3.76%). Apoptosis was also confirmed by changes in the expression levels of apoptosis-related genes (i.e., p53, Bax, Bak, and Bcl2). Downregulated expression of Bcl2 indicates an intrinsic apoptotic pathway. Current results suggest that components of Gelidium latifolium should be further investigated as possible sources of novel antitumor drugs. 相似文献
55.
Hemalatha Murugaiah Chow Lun Teh Kai Chew Loh Ahmad Ramli Mohamad Yahya Nur Asshifa Md Noh Noor Hana Hanif Abu Bakar Daruliza Kernain Rokiah Hashim Yazmin Bustami 《Molecules (Basel, Switzerland)》2021,26(21)
Here, we report the extracellular biosynthesis of silver nanoparticles (AgNPs) and determination of their antibacterial and anticancer properties. We also explore the efficacy of bioAgNPs incorporated in cellulose nanocrystals (CNCs) and alginate (Alg) for the formation of an antibacterial hydrogel film. Streptomyces sp. PBD-311B was used for the biosynthesis of AgNPs. The synthesized bioAgNPs were characterized using UV-Vis spectroscopy, TEM, XRD, and FTIR analysis. Then, the bioAgNPs’ antibacterial and anticancer properties were determined using TEMA and cytotoxicity analysis. To form the antibacterial hydrogel film, bioAgNPs were mixed with a CNC and Alg solution and further characterized using FTIR analysis and a disc diffusion test. The average size of the synthesized bioAgNPs is around 69 ± 2 nm with a spherical shape. XRD analysis confirmed the formation of silver nanocrystals. FTIR analysis showed the presence of protein capping at the bioAgNP surface and could be attributed to the extracellular protein binding to bioAgNPs. The MIC value of bioAgNPs against P. aeruginosa USM-AR2 and MRSA was 6.25 mg/mL and 3.13 mg/mL, respectively. In addition, the bioAgNPs displayed cytotoxicity effects against cancer cells (DBTRG-0.5MG and MCF-7) and showed minimal effects against normal cells (SVG-p12 and MCF-10A), conferring selective toxicity. Interestingly, the bioAgNPs still exhibited inhibition activity when incorporated into CNC/Alg, which implies that the hydrogel film has antibacterial properties. It was also found that bioAgNP-CNC/Alg displayed a minimal or slow release of bioAgNPs owing to the intermolecular interaction and the hydrogel’s properties. Overall, bioAgNP-CNC/Alg is a promising antibacterial hydrogel film that showed inhibition against the pathogenic bacteria P. aeruginosa and MRSA and its application can be further evaluated for the inhibition of cancer cells. It showed benefits for surgical resection of a tumor to avoid post-operative wound infection and tumor recurrence at the surgical site. 相似文献
56.
Yudi Pranoto Brigitta Laksmi Paramita Muhammad Nur Cahyanto Soottawat Benjakul 《Molecules (Basel, Switzerland)》2021,26(20)
Oxidation of tapioca via ozone oxidation was carried out under different conditions in comparison with H2O2. The impact of ozonation on physicochemical properties of tapioca was studied and fried peanuts coated with different tapioca were characterized. Different ozone oxidation times (10, 20, and 30 min) and various pH values (5, 7, and 9) were used for tapioca modification. Tapioca oxidized by ozone for 20 min at pH 7 had higher swelling power (SP), water holding capacity (WHC), oil holding capacity (OHC), and viscosity than the native counterpart (P < 0.05). This coincided with the higher carbonyl and carboxyl contents (P < 0.05). The highest frying expansion (FE) with the lowest hardness was attained for fried peanut coated with tapioca oxidized under the aforementioned condition. Therefore, oxidation of tapioca using ozone under optimal conditions could be a potential means to improve frying expansion as well as the crispiness of the fried coated peanuts. 相似文献
57.
M.Iqbal Choudhary Irfan Baig M. Nur‐e‐Alam S. Shahzad‐ul‐Hussan Purev
ndognii M. Bunderya Z. Oyun Atta‐ur‐Rahman 《Helvetica chimica acta》2001,84(8):2409-2416
The four new and four known sesquiterpenoid derivatives 1 – 4 and 5 – 8 , respectively, were isolated from the air‐dried roots of Ferula mongolica. The structures of these compounds were determined by spectroscopic methods and found to be rel‐(2R,3R)‐2‐[(3E)‐4,8‐dimethylnona‐3,7‐dienyl]‐3,4‐dihydro‐3,8‐dihydroxy‐2‐methyl‐2H,5H‐pyrano[2,3‐b][1]benzopyran‐5‐one ( 1 ), rel‐(2R,3R)‐2‐[(3E)‐4,8‐dimethylnona‐3,7‐dienyl]‐2,3‐dihydro‐7‐hydroxy‐2,3‐dimethyl‐4H‐furo[2,3‐b][1]benzopyran‐4‐one ( 2 ), rel‐(2R,3R)‐2‐[(3E)‐4,8‐dimethylnona‐3,7‐dienyl]‐2,3‐dihydro‐7‐hydroxy‐2,3‐dimethyl‐4H‐furo[3,2‐c][1]benzopyran‐4‐one ( 3 ), rel‐(2R,3R)‐2‐[(3E)‐4,8‐dimethylnona‐3,7‐dienyl]‐2,3‐dihydro‐7‐methoxy‐2,3‐dimethyl‐4H‐furo[3,2‐c][1]benzopyran‐4‐one ( 4 ), (4E,8E)‐1‐(2‐hydroxy‐4‐methoxyphenyl)‐5,9,13‐trimethyltetradeca‐4,8,12‐trien‐1‐one ( 5 ), the rel‐(2R,3S) diastereoisomer 6 of 2 , the rel‐(2R,3S) diastereoisomer 7 of 4 , and (4E,8E)‐1‐(2,4‐dihydroxyphenyl)‐5,9,13‐trimethyltetradeca‐4,8,12‐trien‐1‐one ( 8 ). These compounds were tested as inhibitors against the enzyme α‐glucosidase. The compounds 1 – 6 and 8 exhibited significant inhibitory activity and, therefore, represent a new class of α‐glucosidase inhibitors. 相似文献
58.
The authentication of food products is essential for food quality and safety. Authenticity assessments are important to ensure that the ingredients or contents of food products are legitimate and safe to consume. The metabolomics approach is an essential technique that can be utilized for authentication purposes. This study aimed to summarize food authentication through the metabolomics approach, to study the existing analytical methods, instruments, and statistical methods applied in food authentication, and to review some selected food commodities authenticated using metabolomics-based methods. Various databases, including Google Scholar, PubMed, Scopus, etc., were used to obtain previous research works relevant to the objectives. The review highlights the role of the metabolomics approach in food authenticity. The approach is technically implemented to ensure consumer protection through the strict inspection and enforcement of food labeling. Studies have shown that the study of metabolomics can ultimately detect adulterant(s) or ingredients that are added deliberately, thus compromising the authenticity or quality of food products. Overall, this review will provide information on the usefulness of metabolomics and the techniques associated with it in successful food authentication processes, which is currently a gap in research that can be further explored and improved. 相似文献
59.
Nur Mahammad Felicity J. Ashcroft Astrid J. Feuerherm Samah Elsaadi Esten N. Vandsemb Magne Brset Berit Johansen 《Molecules (Basel, Switzerland)》2021,26(24)
Cytosolic phospholipase A2α (cPLA2α) is the rate-limiting enzyme in releasing arachidonic acid and biosynthesis of its derivative eicosanoids. Thus, the catalytic activity of cPLA2α plays an important role in cellular metabolism in healthy as well as cancer cells. There is mounting evidence suggesting that cPLA2α is an interesting target for cancer treatment; however, it is unclear which cancers are most relevant for further investigation. Here we report the relative expression of cPLA2α in a variety of cancers and cancer cell lines using publicly available datasets. The profiling of a panel of cancer cell lines representing different tissue origins suggests that hematological malignancies are particularly sensitive to the growth inhibitory effect of cPLA2α inhibition. Several hematological cancers and cancer cell lines overexpressed cPLA2α, including multiple myeloma. Multiple myeloma is an incurable hematological cancer of plasma cells in the bone marrow with an emerging requirement of therapeutic approaches. We show here that two cPLA2α inhibitors AVX420 and AVX002, significantly and dose-dependently reduced the viability of multiple myeloma cells and induced apoptosis in vitro. Our findings implicate cPLA2α activity in the survival of multiple myeloma cells and support further studies into cPLA2α as a potential target for treating hematological cancers, including multiple myeloma. 相似文献
60.
A. Zainelabdin S. Zaman G. Amin O. Nur M. Willander 《Applied Physics A: Materials Science & Processing》2012,108(4):921-928
We demonstrate the synthesis and investigate the electrical and optical characteristics of ‘nanocorals’ (NCs) composed of CuO/ZnO grown at low temperature through the hydrothermal approach. High-density CuO nanostructures (NSs) were selectively grown on ZnO nanorods (NRs). The synthesized NCs were used to fabricate p–n heterojunctions that were investigated by the current density–voltage (J–V) and the capacitance–voltage (C–V) techniques. It was found that the NC heterojunctions exhibit a well-defined diode behavior with a threshold voltage of about 1.52 V and relatively high rectification factor of ~760. The detailed forward J–V characteristics revealed that the current transport is controlled by an ohmic behavior for V≤0.15 V, whereas at moderate voltages 1.46≤V<1.5 the current follows a J? α?exp(βV) relationship. At higher voltages (≥1.5 V) the current follows the relation J? α? V 2, indicating that the space-charge-limited current mechanism is the dominant current transport. The C–V measurement indicated that the NC diode has an abrupt junction. The grown CuO/ZnO NCs exhibited a broad light absorption range that is covering the UV and the entire visible parts of the spectrum. 相似文献