Displaying publications 2961 - 2980 of 10390 in total

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  1. Cheong HR, Nguyen NT, Khaw MK, Teoh BY, Chee PS
    Lab Chip, 2018 10 09;18(20):3207-3215.
    PMID: 30229248 DOI: 10.1039/c8lc00776d
    This paper reports a wirelessly powered ionic polymer-metal composite (IPMC) soft actuator operated by external radio frequency (RF) magnetic fields for targeted drug delivery. A 183 μm thick IPMC cantilever valve was fitted with an embedded LC resonant circuit to wirelessly control the actuator when the field frequency is tuned to its resonant frequency of approximately 25 MHz. Experimental characterization of the fabricated actuator showed a cumulative cantilever deflection of 160 μm for three repeated RF ON-OFF cycles at 0.6 W input power. The device was loaded with a dye solution and immersed in DI water to demonstrate wireless drug release. The qualitative result shows the successful release of the dye solution from the device reservoir. The release rate can be controlled by tuning the RF input power. We achieved a maximum average release rate of ∼0.1 μl s-1. We further conducted an in vitro study with human tumor cells (HeLa) to demonstrate the proof of concept of the developed device. The experiments show promising results towards the intended drug delivery application.
    Matched MeSH terms: Dimethylpolysiloxanes/chemistry*; Metals/chemistry*
  2. Bruguière A, Derbré S, Coste C, Le Bot M, Siegler B, Leong ST, et al.
    Fitoterapia, 2018 Nov;131:59-64.
    PMID: 30321650 DOI: 10.1016/j.fitote.2018.10.003
    Usually isolated from Garcinia (Clusiaceae) or Hypericum (Hypericaceae) species, some Polycyclic Polyprenylated AcylPhloroglucinols (PPAPs) have been recently reported as potential research tools for immunotherapy. Aiming at exploring the chemodiversity of PPAPs amongst Garcinia genus, a dereplication process suitable for such natural compounds has been developed. Although less sensitive than mass spectrometry, NMR spectroscopy is perfectly reproducible and allows stereoisomers distinction, justifying the development of 13C-NMR strategies. Dereplication requires the use of databases (DBs). To define if predicted DBs were accurate enough as dereplication tools, experimental and predicted δC of natural products usually isolated from Clusiaceae were compared. The ACD/Labs commercial software allowed to predict 73% of δC in a 1.25 ppm range around the experimental values. Consequently, with these parameters, the major PPAPs from a Garcinia bancana extract were successfully identified using a predicted DB.
    Matched MeSH terms: Plant Extracts/chemistry*; Garcinia/chemistry*
  3. MohdMaidin N, Oruna-Concha MJ, Jauregi P
    Food Chem, 2019 Jan 15;271:224-231.
    PMID: 30236671 DOI: 10.1016/j.foodchem.2018.07.083
    Red grape pomace, a wine-making by-product is rich in anthocyanins and has many applications in food and pharmaceutical industry. However, anthocyanins are unstable during processing and storage. This study aimed to investigate the stability of anthocyanins obtained by hydroalcoholic extraction (with and without sorbic acid) and colloidal gas aphrons (CGA) separation; a surfactant (TWEEN20) based separation. Anthocyanins in CGA samples showed higher stability (half-life = 55 d) than in the crude extract (half-life = 43 d) and their stability increased with the concentration of TWEEN20 in the CGA fraction (6.07-8.58 mM). The anthocyanins loss in the CGA sample (with the maximum content of surfactant, 8.58 mM) was 34.90%, comparable to that in the crude ethanolic extract with sorbic acid (EE-SA) (31.53%) and lower than in the crude extract (44%). Colour stabilisation was also observed which correlated well with the stability of individual anthocyanins in the EE and CGA samples. Malvidin-3-o-glucoside was the most stable anthocyanin over time.
    Matched MeSH terms: Anthocyanins/chemistry; Vitis/chemistry*
  4. Alade IO, Bagudu A, Oyehan TA, Rahman MAA, Saleh TA, Olatunji SO
    Comput Methods Programs Biomed, 2018 Sep;163:135-142.
    PMID: 30119848 DOI: 10.1016/j.cmpb.2018.05.029
    BACKGROUND AND OBJECTIVES: The refractive index of hemoglobin plays important role in hematology due to its strong correlation with the pathophysiology of different diseases. Measurement of the real part of the refractive index remains a challenge due to strong absorption of the hemoglobin especially at relevant high physiological concentrations. So far, only a few studies on direct measurement of refractive index have been reported and there are no firm agreements on the reported values of refractive index of hemoglobin due to measurement artifacts. In addition, it is time consuming, laborious and expensive to perform several experiments to obtain the refractive index of hemoglobin. In this work, we proposed a very rapid and accurate computational intelligent approach using Genetic Algorithm/Support Vector Regression models to estimate the real part of the refractive index for oxygenated and deoxygenated hemoglobin samples.

    METHODS: These models utilized experimental data of wavelengths and hemoglobin concentrations in building highly accurate Genetic Algorithm/Support Vector Regression model (GA-SVR).

    RESULTS: The developed methodology showed high accuracy as indicated by the low root mean square error values of 4.65 × 10-4 and 4.62 × 10-4 for oxygenated and deoxygenated hemoglobin, respectively. In addition, the models exhibited 99.85 and 99.84% correlation coefficients (r) for the oxygenated and deoxygenated hemoglobin, thus, validating the strong agreement between the predicted and the experimental results CONCLUSIONS: Due to the accuracy and relative simplicity of the proposed models, we envisage that these models would serve as important references for future studies on optical properties of blood.

    Matched MeSH terms: Hemoglobins/chemistry*; Oxygen/chemistry*
  5. Lim V, Schneider E, Wu H, Pang IH
    Nutrients, 2018 Oct 26;10(11).
    PMID: 30373159 DOI: 10.3390/nu10111580
    Cataract is an eye disease with clouding of the eye lens leading to disrupted vision, which often develops slowly and causes blurriness of the eyesight. Although the restoration of the vision in people with cataract is conducted through surgery, the costs and risks remain an issue. Botanical drugs have been evaluated for their potential efficacies in reducing cataract formation decades ago and major active phytoconstituents were isolated from the plant extracts. The aim of this review is to find effective phytoconstituents in cataract treatments in vitro, ex vivo, and in vivo. A literature search was synthesized from the databases of Pubmed, Science Direct, Google Scholar, Web of Science, and Scopus using different combinations of keywords. Selection of all manuscripts were based on inclusion and exclusion criteria together with analysis of publication year, plant species, isolated phytoconstituents, and evaluated cataract activities. Scientists have focused their attention not only for anti-cataract activity in vitro, but also in ex vivo and in vivo from the review of active phytoconstituents in medicinal plants. In our present review, we identified 58 active phytoconstituents with strong anti-cataract effects at in vitro and ex vivo with lack of in vivo studies. Considering the benefits of anti-cataract activities require critical evaluation, more in vivo and clinical trials need to be conducted to increase our understanding on the possible mechanisms of action and the therapeutic effects.
    Matched MeSH terms: Plant Extracts/chemistry; Phytochemicals/chemistry
  6. Dabbagh A, Hedayatnasab Z, Karimian H, Sarraf M, Yeong CH, Madaah Hosseini HR, et al.
    Int J Hyperthermia, 2019;36(1):104-114.
    PMID: 30428737 DOI: 10.1080/02656736.2018.1536809
    PURPOSE: Although magnetite nanoparticles (MNPs) are promising agents for hyperthermia therapy, insufficient drug encapsulation efficacies inhibit their application as nanocarriers in the targeted drug delivery systems. In this study, porous magnetite nanoparticles (PMNPs) were synthesized and coated with a thermosensitive polymeric shell to obtain a synergistic effect of hyperthermia and chemotherapy.

    MATERIALS AND METHODS: PMNPs were produced using cetyltrimethyl ammonium bromide template and then coated by a polyethylene glycol layer with molecular weight of 1500 Da (PEG1500) and phase transition temperature of 48 ± 2 °C to endow a thermosensitive behavior. The profile of drug release from the nanostructure was studied at various hyperthermia conditions generated by waterbath, magnetic resonance-guided focused ultrasound (MRgFUS), and alternating magnetic field (AMF). The in vitro cytotoxicity and hyperthermia efficacy of the doxorubicin-loaded nanoparticles (DOX-PEG1500-PMNPs) were assessed using human lung adenocarcinoma (A549) cells.

    RESULTS: Heat treatment of DOX-PEG1500-PMNPs containing 235 ± 26 mg·g-1 DOX at 48 °C by waterbath, MRgFUS, and AMF, respectively led to 71 ± 4%, 48 ± 3%, and 74 ± 5% drug release. Hyperthermia treatment of the A549 cells using DOX-PEG1500-PMNPs led to 77% decrease in the cell viability due to the synergistic effects of magnetic hyperthermia and chemotherapy.

    CONCLUSION: The large pores generated in the PMNPs structure could provide a sufficient space for encapsulation of the chemotherapeutics as well as fast drug encapsulation and release kinetics, which together with thermosensitive characteristics of the PEG1500 shell, make DOX-PEG1500-PMNPs promising adjuvants to the magnetic hyperthermia modality.

    Matched MeSH terms: Polyethylene Glycols/chemistry*; Magnetite Nanoparticles/chemistry*
  7. Monajemi H, Md Zain S, Ishida T, Wan Abdullah WAT
    Biochem. Cell Biol., 2019 08;97(4):497-503.
    PMID: 30444637 DOI: 10.1139/bcb-2018-0220
    The search for the mechanism of ribosomal peptide bond formation is still ongoing. Even though the actual mechanism of peptide bod formation is still unknown, the dominance of proton transfer in this reaction is known for certain. Therefore, it is vital to take the quantum mechanical effects on proton transfer reaction into consideration; the effects of which were neglected in all previous studies. In this study, we have taken such effects into consideration using a semi-classical approach to the overall reaction mechanism. The M06-2X density functional with the 6-31++G(d,p) basis set was used to calculate the energies of the critical points on the potential energy surface of the reaction mechanism, which are then used in transition state theory to calculate the classical reaction rate. The tunnelling contribution is then added to the classical part by calculating the transmission permeability and tunnelling constant of the reaction barrier, using the numerical integration over the Boltzmann distribution for the symmetrical Eckart potential. The results of this study, which accounts for quantum effects, indicates that the A2451 ribosomal residue induces proton tunnelling in a stepwise peptide bond formation.
    Matched MeSH terms: Peptides/chemistry*; Ribosomes/chemistry*
  8. Rasouli E, Basirun WJ, Rezayi M, Shameli K, Nourmohammadi E, Khandanlou R, et al.
    Int J Nanomedicine, 2018;13:6903-6911.
    PMID: 30498350 DOI: 10.2147/IJN.S158083
    Introduction: In the present research, we report a quick and green synthesis of magnetite nanoparticles (Fe3O4-NPs) in aqueous solution using ferric and ferrous chloride, with different percentages of natural honey (0.5%, 1.0%, 3.0% and 5.0% w/v) as the precursors, stabilizer, reducing and capping agent, respectively. The effect of the stabilizer on the magnetic properties and size of Fe3O4-NPs was also studied.

    Methods: The nanoparticles were characterized by X-ray diffraction (XRD) analysis, field emission scanning electron microscopy, energy dispersive X-ray fluorescence, transmission electron microscopy (TEM), vibrating sample magnetometry (VSM) and Fourier transform infrared spectroscopy.

    Results: The XRD analysis indicated the presence of pure Fe3O4-NPs while the TEM images indicated that the Fe3O4-NPs are spherical with a diameter range between 3.21 and 2.22 nm. The VSM study demonstrated that the magnetic properties were enhanced with the decrease in the percentage of honey. In vitro viability evaluation of Fe3O4-NPs performed by using the MTT assay on the WEHI164 cells demonstrated no significant toxicity in higher concentration up to 140.0 ppm, which allows them to be used in some biological applications such as drug delivery.

    Conclusion: The presented synthesis method can be used for the controlled synthesis of Fe3O4-NPs, which could be found to be important in applications in biotechnology, biosensor and biomedicine, magnetic resonance imaging and catalysis.

    Matched MeSH terms: Ferric Compounds/chemistry*; Magnetite Nanoparticles/chemistry*
  9. Low KL, Idris A, Mohd Yusof N
    Food Chem, 2020 Mar 01;307:125631.
    PMID: 31634761 DOI: 10.1016/j.foodchem.2019.125631
    Lutein available in the current market is derived from marigold petals. However, extensive studies showed that microalgae are rich in lutein content and potentially exploitable for its dietary and other industrial applications. In this study, microwave assisted binary phase solvent extraction method (MABS) was the novel protocol being developed and optimized to achieve maximum lutein recovery from microalgae Scenedesmus sp. biomass. Results showed that 60% potassium hydroxide solution with acetone in the ratio of 0.1 (ml/ml) was the ideal binary phase solvent composition. Empirical model developed using response surface methodology revealed highest lutein content can be recovered through MABS extraction method at 55 °C treatment temperature, 36 min in extraction time, 0.7 (mg/ml) for biomass to solvent ratio, 250 Watt microwave power and 250 rpm stirring speed. This optimized novel protocol had increased the amount of lutein recovered by 130% and shorten the overall extraction time by 3-folds.
    Matched MeSH terms: Scenedesmus/chemistry*; Microalgae/chemistry
  10. Tan SP, Tan EN, Lim QY, Nafiah MA
    J Ethnopharmacol, 2020 May 10;253:112610.
    PMID: 31991202 DOI: 10.1016/j.jep.2020.112610
    ETHNOPHARMACOLOGICAL RELEVANCE: Phyllanthus acidus (L.) Skeels is not only used for its edible fruits but also used to treat a wide spectrum of diseases such as inflammatory, rheumatism, bronchitis, asthma, respiratory disorder, hepatic diseases and diabetes in India, Asia, the Caribbean region, and Central and South America. This paper aims to discuss the current understanding regarding the traditional uses, phytochemical and pharmacological studies of P. acidus, and their possible research opportunities.

    MATERIALS AND METHODS: All information on P. acidus was collected from various electronic database (ACS, PubMed, Scopus, Web of Science, SciFinder, Science Direct, Google Scholar, Springer, Wiley, Taylor and Mendeley) and also from those published materials (Ph.D. and M.Sc. dissertations and books) by using a combination of various meaningful keywords.

    RESULTS: Phytochemical analyses on barks, leaves, roots and fruits of P. acidus identified triterpene, diterpene, sesquiterpene, and glycosides as predominant classes of bioactive substances found in this plant. P. acidus was reported with various pharmacological activities such as in vivo hepatoprotective and hypoglycemic, in vitro anti-oxidant, α-glucosidase inhibitory, anti-inflammatory and antimicrobial activities. However, none of these studies are with clinical research. Some of the studies were performed with only a single set of experiments or with a high dose of extract, and thus the validity of the experimental data may be questionable. In addition, most of the studies described were without identifying the effective components. Some of the assays were even without a positive control for comparison which makes results questionable.

    CONCLUSION: Although P. acidus has been proven as a valuable medicinal source from its traditional uses. However, the pharmacological experiments conducted were not sufficient to verify its traditional uses. More investigation is required to confirm the traditional claims such as bioassay-guided isolation of bioactive compounds, detailed pharmacological investigations, clinical studies, and its toxicity investigation. Additionally, an experimental design with sufficient data replication, the use of controls and authenticated research materials, and the selection of a rationale dose or concentration for the analysis are keys to providing reproducible experimental data.

    Matched MeSH terms: Plant Preparations/chemistry; Phyllanthus/chemistry*
  11. Yap JY, Hii CL, Ong SP, Lim KH, Abas F, Pin KY
    J Sci Food Agric, 2020 May;100(7):2932-2937.
    PMID: 32031257 DOI: 10.1002/jsfa.10320
    BACKGROUND: Papaya is widely grown in Malaysia and normally only the fruits are consumed. Other parts of the plant such as leaves, roots, bark, peel, seeds and pulp are also known to have medicinal properties and have been used to treat various diseases. Papaya leaves also contain flavonoids, alkaloids phenolic compounds and cynogenetic compounds, and are also reported to be able to treat dengue fever.

    RESULTS: Studies were carried out on drying of papaya leaves using hot air (60, 70 and 80 °C), shade and freeze drying. Effective diffusivities were estimated ranging from 2.09 × 10-12 to 2.18 × 10-12 m2 s-1 from hot air drying, which are within the order of magnitudes reported for most agricultural and food products. The activation energy to initiate drying showed a relatively low value (2.11 kJ mol-1 ) as a result of the thin leave layer that eased moisture diffusion. In terms of total polyphenols content and antioxidant activities, freeze-dried sample showed a significantly higher (P 

    Matched MeSH terms: Plant Leaves/chemistry; Carica/chemistry*
  12. Khandaker MU, Shuaibu HK, Alklabi FAA, Alzimami KS, Bradley DA
    Health Phys, 2019 06;116(6):789-798.
    PMID: 30889102 DOI: 10.1097/HP.0000000000001042
    The presence of natural radionuclides in the food chain point to a need to assess concentration levels and concomitant radiological risk. Highly popular and forming a staple part of the diet in North Africa, the Arabian Peninsula, and West Asia, palm dates growing naturally there have even greater marketability than simple satisfaction of domestic demand, the palm dates representing a valuable export item. Accurate knowledge of the levels of natural radioactivity in the fruit is thus of importance. In this study, using high-purity germanium gamma-ray spectrometry, quantification has been made of natural radionuclide concentrations in imported dates originating from Iran, Saudi Arabia, and Tunisia. Sample analyses reveal respective mean activity concentrations of 1.4 ± 0.3, 0.8 ± 0.4, and 186 ± 9 Bq kg dry weight for Ra, Ra, and K. For each nuclide, the mean concentration varies little between the dates of the three represented regions. The estimated committed effective dose resulting from the consumption of date fruits for a typical adult was found to be 29.9 μSv y, well below the global internal dose of 290 μSv y assessed by the United Nations Scientific Committee on the Effects of Atomic Radiation to be due to food and water intake. Similarly, the excess lifetime cancer risk due to naturally occurring radioactive material exposure via date fruit consumption is seen to be below the International Commission on Radiological Protection cancer risk factor of 2.5 × 10 based on the additional annual dose limit of 1 mSv for a member of the general public. The results show no significant uptake in the analyzed date fruits.
    Matched MeSH terms: Fruit/chemistry*; Phoeniceae/chemistry*
  13. Chen JH, Liu L, Lim PE, Wei D
    Bioprocess Biosyst Eng, 2019 Jul;42(7):1129-1142.
    PMID: 30919105 DOI: 10.1007/s00449-019-02110-z
    Microalgal lipid production by Chlorella protothecoides using sugarcane bagasse hydrolysate was investigated in this study. First, maximum glucose and reducing sugar concentrations of 15.2 and 27.0 g/L were obtained in sugarcane bagasse hydrolysate (SCBH), and the effects of different percentages of glucose and xylose on algal cultivation were investigated. Afterwards, SCBH was used as a carbon source for the cultivation of C. protothecoides and higher biomass concentration of 10.7 g/L was achieved. Additionally, a large amount of fatty acids, accounting up to 16.8% of dry weight, were accumulated in C. protothecoides in the nitrogen-limited (0.1-1 mmol/L) culture. Although SCBH inhibited fatty acid accumulation to a certain degree and the inhibition was aggravated by nitrogen starvation, SCBH favored microalgal cell growth and fatty acid production. The present study is of significance for the integration of cost-effective feedstocks production for biodiesel with low-cost SCBH as well as environmentally friendly disposal of lignocellulosic wastes.
    Matched MeSH terms: Cellulose/chemistry*; Saccharum/chemistry*
  14. Li S, Li C, Yang Y, He X, Zhang B, Fu X, et al.
    Food Chem, 2019 Jun 15;283:437-444.
    PMID: 30722895 DOI: 10.1016/j.foodchem.2019.01.020
    The present study aimed at investigating the effects of octenylsuccinylation and particle size on the emulsifying properties of starch granules as Pickering emulsifiers. Starch spherulites (1-5 μm), native rice starch (5-10 μm), waxy maize starch (10-20 μm) and waxy potato starch (20-30 μm) were modified with octenylsuccinic anhydride. Results showed that octenylsuccinylation caused a significant increase in the contact angle, and there was a weak positive linear correlation with the emulsifying capacity of the starch granules. After octenylsuccinylation, smaller particles of octenylsuccinate-starch granules exhibited better emulsifying properties with smaller droplet size and lower creaming index. Overall, both octenylsuccinylation and particle size have important effects on the emulsifying properties of starch granules as Pickering stabilizers. This study could be useful in the design and development of starch-based Pickering emulsifiers, and provide potential applications in the food and pharmaceutical industries.
    Matched MeSH terms: Starch/chemistry*; Emulsifying Agents/chemistry*
  15. Ibrahim NUA, Abd Aziz S, Hashim N, Jamaludin D, Khaled AY
    J Food Sci, 2019 Apr;84(4):792-797.
    PMID: 30861127 DOI: 10.1111/1750-3841.14436
    Total polar compounds (TPC) and free fatty acids (FFA) are important indicators in evaluating the quality of frying oil. Conventional methods to determine TPC and FFA are often time consuming, involved laboratory analyses which required skilled personnel and used substantial amount of harmful solvent. In this study, dielectric spectroscopy technique was used to investigate the relation between dielectric property of refined, bleached and deodorized palm olein (RBDPO) during deep frying with TPC and FFA. In total, 150 batches of French fries were intermittently fried at 185 ± 5 °C for 7 hr a day over 5 consecutive days. A total of 30 frying oil samples were collected. The dielectric property of frying oil samples were measured using impedance analyzer with frequencies ranging from 100 Hz to 10 MHz. The TPC of frying oil samples were measured with a Testo 270, while the FFA analysis was done using Malaysian Palm Oil Board (MPOB) test method. Results showed that dielectric constant, TPC and FFA of RBDPO increased as the frying time increased. Dielectric constant increased from 3.09 to 3.17, while TPC and FFA increased from 9.96 to 19.52 and from 0.08% to 0.36%, respectively. Partial least square (PLS) analysis produced good prediction of TPC and FFA with the application of genetic algorithm (GA). Model developed for prediction of TPC and FFA yielded highly significant correlation with R2 of 0.91 and 0.95, respectively and both had root mean square error in cross-validation (RMSECV) of 1.06%. This study demonstrates the potential of dielectric spectroscopy in monitoring palm olein degradation during frying. PRACTICAL APPLICATION: The application of dielectric spectroscopy to detect degradation of palm olein during frying was studied. The dielectric property of palm olein during frying has successfully correlated with TPC and FFA. The model developed in this study could be used for the development of a sensing system for palm olein degradation monitoring.
    Matched MeSH terms: Fatty Acids, Nonesterified/chemistry; Solanum tuberosum/chemistry
  16. Yunus NA, Mazlan SA, Ubaidillah, Abdul Aziz SA, Tan Shilan S, Abdul Wahab NA
    Int J Mol Sci, 2019 Feb 10;20(3).
    PMID: 30744210 DOI: 10.3390/ijms20030746
    Determination of the thermal characteristics and temperature-dependent rheological properties of the magnetorheological elastomers (MREs) is of paramount importance particularly with regards to MRE applications. Hitherto, a paucity of temperature dependent analysis has been conducted by MRE researchers. In this study, an investigation on the thermal and rheological properties of epoxidized natural rubber (ENR)-based MREs was performed. Various percentages of carbonyl iron particles (CIPs) were blended with the ENR compound using a two roll-mill for the preparation of the ENR-based MRE samples. The morphological, elemental, and thermal analyses were performed before the rheological test. Several characterizations, as well as the effects of the strain amplitude, temperature, and magnetic field on the rheological properties of ENR-based MRE samples, were evaluated. The micrographs and elemental results were well-correlated regarding the CIP and Fe contents, and a uniform distribution of CIPs was achieved. The results of the thermal test indicated that the incorporation of CIPs enhanced the thermal stability of the ENR-based MREs. Based on the rheological analysis, the storage modulus and loss factor were dependent on the CIP content and strain amplitude. The effect of temperature on the rheological properties revealed that the stiffness of the ENR-based MREs was considered stable, and they were appropriate to be employed in the MRE devices exposed to high temperatures above 45 °C.
    Matched MeSH terms: Rubber/chemistry*; Elastomers/chemistry*
  17. Alizamir M, Kisi O, Ahmed AN, Mert C, Fai CM, Kim S, et al.
    PLoS One, 2020;15(4):e0231055.
    PMID: 32287272 DOI: 10.1371/journal.pone.0231055
    Soil temperature has a vital importance in biological, physical and chemical processes of terrestrial ecosystem and its modeling at different depths is very important for land-atmosphere interactions. The study compares four machine learning techniques, extreme learning machine (ELM), artificial neural networks (ANN), classification and regression trees (CART) and group method of data handling (GMDH) in estimating monthly soil temperatures at four different depths. Various combinations of climatic variables are utilized as input to the developed models. The models' outcomes are also compared with multi-linear regression based on Nash-Sutcliffe efficiency, root mean square error, and coefficient of determination statistics. ELM is found to be generally performs better than the other four alternatives in estimating soil temperatures. A decrease in performance of the models is observed by an increase in soil depth. It is found that soil temperatures at three depths (5, 10 and 50 cm) could be mapped utilizing only air temperature data as input while solar radiation and wind speed information are also required for estimating soil temperature at the depth of 100 cm.
    Matched MeSH terms: Soil/chemistry*; Rivers/chemistry
  18. Ahmad N, Colak B, Gibbs MJ, Zhang DW, Gautrot JE, Watkinson M, et al.
    Biomacromolecules, 2019 07 08;20(7):2506-2514.
    PMID: 31244015 DOI: 10.1021/acs.biomac.9b00245
    Inflammatory conditions are frequently accompanied by increased levels of active proteases, and there is rising interest in methods for their detection to monitor inflammation in a point of care setting. In this work, new sensor materials for disposable single-step protease biosensors based on poly(2-oxazoline) hydrogels cross-linked with a protease-specific cleavable peptide are described. The performance of the sensor material was assessed targeting the detection of matrix metalloproteinase-9 (MMP-9), a protease that has been shown to be an indicator of inflammation in multiple sclerosis and other inflammatory conditions. Films of the hydrogel were formed on gold-coated quartz crystals using thiol-ene click chemistry, and the cross-link density was optimized. The degradation rate of the hydrogel was monitored using a quartz crystal microbalance (QCM) and showed a strong dependence on the MMP-9 concentration. A concentration range of 0-160 nM of MMP-9 was investigated, and a lower limit of detection of 10 nM MMP-9 was determined.
    Matched MeSH terms: Oxazoles/chemistry*; Peptides/chemistry*
  19. Hamada T, Harano K, Niihara R, Kitahara H, Yamamoto M, Vairrapan CS, et al.
    J Oleo Sci, 2020;69(6):643-648.
    PMID: 32493886 DOI: 10.5650/jos.ess19296
    Sour citrus are prized for their flavor and fragrance. This work identified the components of the peel oil of Hetsuka-daidai (Citrus sp. hetsukadaidai), a special sour citrus that is native to the southern part of the Osumi peninsula, Kagoshima, Japan. These compounds were compared to those identified from the peels of six other major sour citrus: lime (Citrus latifolia), lemon (Citrus limon), Yuzu (Citrus junos), Kabusu (Citrus aurantium), Kabosu (Citrus sphaerocarpa), and Sudachi (Citrus sudachi). Peel oil contents were analyzed for the duration of four months during harvest season to investigate the differences in peel oil/fragrance during ripening. These results could facilitate the development of preferred flavor and scent profiles using local species.
    Matched MeSH terms: Citrus/chemistry*; Oils, Volatile/chemistry*
  20. Kadir R, Awang K, Khamaruddin Z, Soit Z
    An Acad Bras Cienc, 2015 Apr-Jun;87(2):743-51.
    PMID: 26131633 DOI: 10.1590/0001-3765201520140041
    Wood extractives from heartwood of Callophylum inophyllum (bintangor) were obtained by shaker method and analyzed for their constituents by gas chromatography-mass spectrometry (GC-MS). Ten compounds were identified by ethanol (EtOH) solvents, fourteen by methanol (MeOH) and only nine by petroleum ether (PETETHR). Major compounds were contributed by monoterpenes (75.11%, 53.75%) when extracted with EtOH and PETETHR solvents. The anti-termitic assay of the wood extracts was also investigated against Coptotermes curvignathus. The level of concentration for anti-termite activity may be an indication of the dose application of the wood extracts for new development of termiticide.
    Matched MeSH terms: Wood/chemistry; Calophyllum/chemistry*
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