Search results for: plasma electrolytic oxide

Authors: Manfred Szerencsits, Christine Weinberger, Maximilian Kuderna, Franz Feichtinger, Eva Erhart, Stephan Maier

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Cover or catch crops have beneficial effects for soil, water, erosion, etc. If harvested, they also provide feedstock for biogas without competition for arable land in regions, where only one main crop can be produced per year. On average gross energy yields of approx. 1300 m³ methane (CH₄) ha^-1 can be expected from 4.5 tonnes (t) of cover crop dry matter (DM) in Austria. Considering the total energy invested from cultivation to compression for biofuel use a net energy yield of about 1000 m³ CH₄ ha^-1 is remaining. With the straw of grain maize or Corn Cob Mix (CCM) similar energy yields can be achieved. In comparison to catch crops remaining on the field as green manure or to complete fallow between main crops the effects on soil, water and climate can be improved if cover crops are harvested without soil compaction and digestate is returned to the field in an amount equivalent to cover crop removal. In this way, the risk of nitrate leaching can be reduced approx. by 25% in comparison to full fallow. The risk of nitrous oxide emissions may be reduced up to 50% by contrast with cover crops serving as green manure. The effects on humus content and erosion are similar or better than those of cover crops used as green manure when the same amount of biomass was produced. With higher biomass production the positive effects increase even if cover crops are harvested and the only digestate is brought back to the fields. The ecological footprint of arable farming can be reduced by approx. 50% considering the substitution of natural gas with CH₄ produced from cover crops.

Keywords: biogas, cover crops, catch crops, land use competition, sustainable agriculture

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Authors: Miao Zhang, Limin Liu, Feng Zhi, Panpan Niu, Mengya Yang, Xuemei Zhu, Ying Diao, Jun Wang, Ying Zhao

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Background and Aims: Clinical studies have demonstrated that serum semicarbazide-sensitive amine oxidase (SSAO) activities positively correlate with the progression of atherosclerosis. The aim of the present study is to investigate the effect of SSAO inactivation on the development of atherosclerosis. Methods: Female LDLr knockout (KO) mice were given the Western-type diet for 6 and 9 weeks to induce the formation of early and advanced lesions, and semicarbazide (SCZ, 0.125%) was added into the drinking water to inactivate SSAO in vivo. Results: Despite no impact on plasma total cholesterol levels, abrogation of SSAO by SCZ not only resulted in the enlargement of both early (1.5-fold, p=0.0043) and advanced (1.8-fold, p=0.0013) atherosclerotic lesions, but also led to reduced/increased lesion contents of macrophages/smooth muscle cells (SMCs) (macrophage: ~0.74-fold, p=0.0002(early)/0.0016(advanced); SMC: ~1.55-fold, p=0.0003(early) /0.0001(advanced)), respectively. Moreover, SSAO inactivation inhibited the migration of circulating monocytes into peripheral tissues and reduced the amount of circulating Ly6Chigh monocytes (0.7-fold, p=0.0001), which may account for the reduced macrophage content in lesions. In contrast, the increased number of SMCs in lesions of SCZ-treated mice is attributed to an augmented synthetic vascular SMC phenotype switch as evidenced by the increased proliferation of SMCs and accumulation of collagens in vivo. Conclusion: SSAO inactivation by SCZ promotes the phenotypic switch of SMCs and the development of atherosclerosis. The enzymatic activity of SSAO may thus represent a potential target in the prevention and/or treatment of atherosclerosis.

Keywords: atherosclerosis, phenotype switch of smooth muscle cells, SSAO/VAP-1, semicarbazide

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Authors: Ahmad Rasyadan Arshad, A. Rahman A. Jamal, N. Mohamed Ibrahim, Nor Azian Abdul Murad

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Introduction: Parkinson’s disease (PD) is a complex and asymptomatic disease where patients are usually diagnosed at late stage where about 70% of the dopaminergic neurons are lost. Therefore, identification of molecular biomarkers is crucial for early diagnosis of PD. MicroRNA (miRNA) is a short nucleotide non-coding small RNA which regulates the gene expression in post-translational process. The involvement of these miRNAs in neurodegenerative diseases includes maintenance of neuronal development, necrosis, mitochondrial dysfunction and oxidative stress. Thus, miRNA could be a potential biomarkers for diagnosis of PD. Objective: This study aim to identify the miRNA involved in Late Onset PD (LOPD) and Early Onset PD (EOPD) compared to the controls. Methods: This is a case-control study involved PD patients in the Chancellor Tunku Muhriz Hospital at the UKM Medical Centre. miRNA samples were extracted using miRNeasy serum/plasma kit from Qiagen. The quality of miRNA extracted was determined using Agilent RNA 6000 Nano kit in the Bioanalyzer. miRNA expression was performed using GeneChip miRNA 4.0 chip from Affymetrix. Microarray was performed in EOPD (n= 7), LOPD (n=9) and healthy control (n=11). Expression Console and Transcriptomic Analyses Console were used to analyze the microarray data. Result: miR-129-5p was significantly downregulated in EOPD compared to LOPD with -4.2 fold change (p = <0.050. miR-301a-3p was upregulated in EOPD compared to healthy control (fold = 10.3, p = <0.05). In LOPD versus healthy control, miR-486-3p (fold = 15.28, p = <0.05), miR-29c-3p (fold = 12.21, p = <0.05) and miR-301a-3p (fold = 10.01, p =< 0.05) were upregulated. Conclusion: Several miRNA have been identified to be differentially expressed in EOPD compared to LOPD and PD versus control. These miRNAs could serve as the potential biomarkers for early diagnosis of PD. However, these miRNAs need to be validated in a larger sample size.

Keywords: early onset PD, late onset PD, microRNA (miRNA), microarray

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Authors: Amirhossein Moghanian, Morteza Elsa, Mehrnaz Aminitabar

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Modified bioactive glass has been considered as a promising multifunctional candidate in bone repair and regeneration due to its attractive properties. The present study mainly aims to evaluate how the individual substitution of lithium (L-BG) and magnesium (M-BG) for calcium can affect the in vitro bioactivity of sol-gel derived substituted 58S bioactive glass (BG); and to present one composition in both of the 60SiO2–(36-x)CaO–4P₂O₅–(x)Li₂O and 60SiO₂ –(36-x)CaO–4P₂O₅–(x)MgO quaternary systems (where x= 0, 5, 10 mol.%) with improved biocompatibility, enhanced alkaline phosphatase (ALP) activity, and the most efficient antibacterial activity against methicillin-resistant staphylococcus aureus bacteria. To address these aims, and study the effect of CaO/Li₂O and CaO/MgO substitution up to 10 mol % in 58S-BGs, the samples were characterized by X-ray diffraction, Fourier transform infrared spectroscopy, inductively coupled plasma atomic emission spectrometry and scanning electron microscopy after immersion in simulated body fluid up to 14 days. Results indicated that substitution of either CaO/ Li₂O and CaO/ MgO had a retarding effect on in vitro hydroxyapatite (HA) formation due to the lower supersaturation degree for nucleation of HA compared with 58s-BG. Meanwhile, magnesium had a more pronounced effect. The 3-(4,5dimethylthiazol-2-yl)-2,5-diphenyltetrazolium bromide (MTT) and alkaline phosphatase (ALP) assays showed that both substitutions of CaO/ Li₂O and CaO/ MgO up to 5mol % in 58s-BGs led to increased biocompatibility and stimulated proliferation of the pre-osteoblast MC3T3 cells with respect to the control. On the other hand, the substitution of either Li or Mg for Ca in the 58s BG composition resulted in improved bactericidal efficiency against MRSA bacteria. Taken together, sample 58s-BG with 5 mol % CaO/Li₂O substitution (BG-5L) was considered as a multifunctional biomaterial in bone repair/regeneration with improved biocompatibility, enhanced ALP activity as well as significant antibacterial activity against methicillin-resistant staphylococcus aureus (MRSA) bacteria.

Keywords: alkaline, alkaline earth, bioactivity, biomedical applications, sol-gel processes

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Authors: Rehan Deshmukh, Sunil Bhand, Utpal Roy

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We report the label-free electrochemical detection of Escherichia coli O157:H7 (ATCC 43895) in potable water using a DNA probe as a sensing molecule targeting the open reading frame marker. Indium tin oxide (ITO) surface was modified with organosilane and, glutaraldehyde was applied as a linker to fabricate the DNA sensor chip. Non-Faradic electrochemical impedance spectroscopy (EIS) behavior was investigated at each step of sensor fabrication using cyclic voltammetry, impedance, phase, relative permittivity, capacitance, and admittance. Atomic force microscopy (AFM) and scanning electron microscopy (SEM) revealed significant changes in surface topographies of DNA sensor chip fabrication. The decrease in the percentage of pinholes from 2.05 (Bare ITO) to 1.46 (after DNA hybridization) suggested the capacitive behavior of the DNA sensor chip. The results of non-Faradic EIS studies of DNA sensor chip showed a systematic declining trend of the capacitance as well as the relative permittivity upon DNA hybridization. DNA sensor chip exhibited linearity in 0.5 to 25 pg/10mL for E. coli O157:H7 (ATCC 43895). The limit of detection (LOD) at 95% confidence estimated by logistic regression was 0.1 pg DNA/10mL of E. coli O157:H7 (equivalent to 13.67 CFU/10mL) with a p-value of 0.0237. Moreover, the fabricated DNA sensor chip used for detection of E. coli O157:H7 showed no significant cross-reactivity with closely and distantly related bacteria such as Escherichia coli MTCC 3221, Escherichia coli O78:H11 MTCC 723 and Bacillus subtilis MTCC 736. Consequently, the results obtained in our study demonstrated the possible application of developed DNA sensor chips for E. coli O157:H7 ATCC 43895 in real water samples as well.

Keywords: capacitance, DNA sensor, Escherichia coli O157:H7, open reading frame marker

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Authors: Santram Lodhi, Alok Pal Jain, Awesh K. Yadav, Gopal Rai

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Rhodiola rosea L. (Crassulaceae) is commonly known as golden root or rose root. It is a perennial herbaceous plant and most investigated species of the genus Rhodiola. Rhodiola rosea contains flavonoids, terpenoids, phenylpropanoid glycosides and phenylethanol derivatives in the roots of the plant. The objective of present study was to investigate the protective effect of hydroalcoholic extract from Rhodiola rosea roots in DSS induced colitis in mice. The ulcerative colitis was induced by DSS (3%, w/v) in mice and estimated weight loss and stool consistency. Various parameters including Colon length, spleen weights and ulcer index were also measured. The histological observations were observed by H&E staining. Effect of hydroalcoholic extract on various antioxidant parameter of rat colon such as tissue myeloperoxidase (MPO), reduced GSH, SOD concentrations and lipid peroxidation were determined. Pro-inflammatory mediators, such as tumour necrosis factor-α (TNF-α) and nitric oxide (NO) were determined by ELISA. In DSS induced group, mice body weight decreased gradually as compared to the control group. Redness and edema were observed in the colons intensely and scores representing inflammation in this group. The extract treated showed with tissue levels of TNF-α, IL-6 and MPO activity were significantly (p<0.05) increased. The mice treated with higher doses of hydroalcoholic extract (300 mg/kg) significantly reduced the activity compared with standard drug sulfasalazine (100 mg/kg. B.wt). Conclusion: Results of this study were suggested that the efficacy of hydroalcoholic extract, especially at the higher dose, was similar to that of standard drug, which concerned its potential application as a natural medicine for the treatment of ulcerative colitis.

Keywords: phenylpropanoid, Rhodiola rosea, sulfasalazin, ulcerative colitis

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Authors: Sharon Waichman, Shahaf Froim, Ido Zukerman, Shmuel Barzilai, Shmual Hayun, Avi Raveh

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Boron carbide is a ceramic material with superior properties such as high chemical and thermal stability, high hardness and high wear resistance. Moreover, it has a big cross section for neutron absorption and therefore can be employed in nuclear based applications. However, an efficient attachment of boron carbide to a metal such as aluminum can be very challenging, mainly because of the formation of aluminum-carbon bonds that are unstable in humid environment, the affinity of oxygen to the metal and the different thermal expansion coefficients of the two materials that may cause internal stresses and a subsequent failure of the bond. Here, we aimed to achieving a strong and a durable attachment between the boron carbide coating and the aluminum substrate. For this purpose, we applied Ti as a thin intermediate layer that provides a gradual change in the thermal expansion coefficients of the configured layers. This layer is continuous and therefore prevents the formation of aluminum-carbon bonds. Boron carbide coatings with a thickness of 1-5 µm were deposited on the aluminum substrate by pulse-DC magnetron sputtering. Prior to the deposition of the boron carbide layer, the surface was pretreated by energetic ion plasma followed by deposition of the Ti intermediate adhesive layer in a continuous process. The properties of the Ti intermediate layer were adjusted by the bias applied to the substrate. The boron carbide/aluminum bond was evaluated by various methods and complementary techniques, such as SEM/EDS, XRD, XPS, FTIR spectroscopy and Glow Discharge Spectroscopy (GDS), in order to explore the structure, composition and the properties of the layers and to study the adherence mechanism of the boron carbide/aluminum contact. Based on the interfacial bond characteristics, we propose a desirable solution for improved adhesion of boron carbide to aluminum using a highly efficient intermediate adhesive layer.

Keywords: adhesion, boron carbide coatings, ceramic/metal bond, intermediate layer, pulsed-DC magnetron sputtering

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Authors: Elshymaa A. Abdelnaby, Amal M. Abo El-Maaty

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This study aimed to investigate dynamics of dominant and subordinate follicles change in dimensions, vascularity and angiogenic hormones after completing deviation till ovulation. Five cyclic mares were subjected to daily blood sampling and rectal Doppler ultrasonographic examination along two estrous cycles. Using electronic calipers, three diameters were recorded for each follicle to estimate area and volume. Leptin, Insulin-like growth factor-I (IGF-1), nitric oxide (NO) and estradiol (E2) were measured. Area of color- and power- Doppler modes with area and circumference of the first (preovulatory) and subordinate follicles were measured in pixels. Follicles were classified into F1O (preovulatory), F2O (subordinate), F3O (third ovulatory) on the dominant ovary and F1C (first contra) and F2C (second contra) on the contralateral ovary. Days before ovulation significantly (P < 0.0001) affected diameter, circumference, area, volume, area/pixel and antrum area of the preovulatory follicle. With the increase of diameter, area, volume area/pixel, antrum area/pixel and circumference of F1O, those of all subordinates were decreasing. The blue blood flow area, power and power minus red blood flow area of F1O increased from day -6 till day of ovulation (day 0), but red blood flow area significantly decreased. F1O had the lowest percent of colored pixels and percent of the colored pixels without antrum. Estradiol and leptin increased from day -6 till day 0 but IGF-1 decreased till day -1 but NO achieved a peak on day -3 then decreased till day 0. In conclusion, antrum growth, blood flow and angiogenic hormones play a role in maturation and ovulation of the dominant follicle in mares.

Keywords: angiogenic hormones, blood flow, mare, preovulatory follicle

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Authors: Mohannad Mayyas, Farshid Pahlevani, Veena Sahajwalla

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Automotive shredder residue (ASR) is an industrial waste, generated during the recycling process of End-of-life vehicles. The large increasing production volumes of ASR and its hazardous content have raised concerns worldwide, leading some countries to impose more restrictions on ASR waste disposal and encouraging researchers to find efficient solutions for ASR processing. Although a great deal of research work has been carried out, all proposed solutions, to our knowledge, remain commercially and technically unproven. While the volume of waste materials continues to increase, the production of materials from new sustainable sources has become of great importance. Advanced ceramic materials such as nitrides, carbides and borides are widely used in a variety of applications. Among these ceramics, a great deal of attention has been recently paid to Titanium nitride (TiN) owing to its unique characteristics. In our study, we propose a new sustainable approach for ASR management where TiN nanoparticles with ideal particle size ranging from 200 to 315 nm can be synthesized as a by-product. In this approach, TiN is thermally synthesized by nitriding pressed mixture of automotive shredder residue (ASR) incorporated with titanium oxide (TiO2). Results indicated that TiO2 influences and catalyses degradation reactions of ASR and helps to achieve fast and full decomposition. In addition, the process resulted in titanium nitride (TiN) ceramic with several unique structures (porous nanostructured, polycrystalline, micro-spherical and nano-sized structures) that were simply obtained by tuning the ratio of TiO2 to ASR, and a product with appreciable TiN content of around 85% was achieved after only one hour nitridation at 1550 °C.

Keywords: automotive shredder residue, nano-ceramics, waste treatment, titanium nitride, thermal conversion

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Authors: Samane Maroufi, Rasoul Khayyam Nekouei, Sajjad Mofarah

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Fabrication of the state-of-the-art portable pseudocapacitors with the desired transparency, mechanical flexibility, capacitance, and durability is challenging. In most cases, the fabrication of such devices requires critical elements which are either under the crisis of depletion or their extraction from virgin mineral ores have sever environmental impacts. This urges the use of secondary resources instead of virgin resources in fabrication of advanced devices. In this research, ultrathin films of defect-rich Mn1−x−y(CexLay)O2−δ with controllable thicknesses in the range between 5 nm to 627 nm and transmittance (≈29–100%) have been fabricated via an electrochemical chronoamperometric deposition technique using an aqueous precursor derived during the selective purification of rare earth oxide (REOs) isolated from end-of-life nickel-metal hydride (Ni-MH) batteries. Intercalation/de-intercalation of anionic O2− through the atomic tunnels of the stratified Mn1−x−y(CexLay)O2−δ crystallites was found to be responsible for outstanding areal capacitance of 3.4 mF cm−2 of films with 86% transmittance. The intervalence charge transfer among interstitial Ce/La cations and Mn oxidation states within the Mn1−x−y(CexLay)O2−δ structure resulted in excellent capacitance retention of ≈90% after 16 000 cycles. The synthesised transparent flexible Mn1−x−y(CexLay)O2−δ full-cell pseudocapacitor device possessed the energy and power densities of 0.088 μWh cm⁻² and 843 µW cm⁻², respectively. These values show insignificant changes under vigorous twisting and bending to 45–180° confirming these value-added materials are intriguing alternatives for size-sensitive energy storage devices. This research confirms the feasibility of utilisation of secondary waste resources for the fabrication of high-quality pseudocapacitors with engineered defects with the desired flexibility, transparency, and cycling stability suitable for size-sensitive portable electronic devices.

Keywords: pseudocapacitors, energy storage devices, flexible and transparent, sustainability

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Authors: Patricia Jayshree Jacob, Mas Jaffri Masarudinb, Mohd Zobir Hussein, Raha Abdul Rahim

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Iron based ferromagnetic nanoparticles (IONP) and silver nanostructures (AgNP) have found a wide range of application in antimicrobial therapy, cell targeting, and environmental applications. As such, the design of well-defined monodisperse IONPs and AgNPs have become an essential tool in nanotechnology. Fabrication of these nanostructures using conventional methods is not environmentally conducive and weigh heavily on energy and outlays. Selected microorganisms possess the innate ability to reduce metallic ions in colloidal aqueous solution to generate nanoparticles. Hence, harnessing this potential is a way forward in constructing microbial nano-factories, capable of churning out high yields of well-defined IONP’s and AgNP's with physicochemical characteristics on par with the best synthetically produced nanostructures. In this paper, we report the isolation and characterization of bacterial strains isolated from the tropical marine and freshwater ecosystems of Malaysia that demonstrated facile and rapid generation of ferromagnetic nanoparticles and silver nanostructures when precursors such as FeCl₃.6H₂O and AgNO₃ were added to the cell-free bacterial lysate in colloidal solution. Characterization of these nanoparticles was carried out using FESEM, UV Spectrophotometer, XRD, DLS and FTIR. This aerobic bioprocess was carried out at ambient temperature and humidity and has the potential to be developed for environmental friendly, cost effective large scale production of IONP’s. A preliminary bioprocess study on the harvesting time, incubation temperature and pH was also carried out to determine pertinent abiotic parameters contributing to the optimal production of these nanostructures.

Keywords: iron oxide nanoparticles, silver nanoparticles, biosynthesis, aquatic bacteria

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Authors: Anza-Vhudziki Mboyi, Ilunga Kamika, Maggy Momba

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The aim of this study was to ascertain the survival limit and capability of commonly found wastewater protozoan (Aspidisca sp, Trachelophyllum sp, and Peranema sp) and bacterial (Bacillus licheniformis, Brevibacillus laterosporus, and Pseudomonas putida) species to remove COD while exposed to commercial nanomaterials under varying pH conditions. The experimental study was carried out in modified mixed liquor media adjusted to various pH levels (pH 2, 7 and 10), and a comparative study was performed to determine the difference between the cytotoxicity effects of commercial zinc oxide (nZnO) and silver (nAg) nanomaterials (NMs) on the target wastewater microbial communities using standard methods. The selected microbial communities were exposed to lethal concentrations ranging from 0.015 g/L to 40 g/L for nZnO and from 0.015 g/L to 2 g/L for nAg for a period of 5 days of incubation at 30°C (100 r/min). Compared with the absence of NMs in wastewater mixed liquor, the relevant environmental concentration ranging between 10 µg/L and 100 µg/L, for both nZnO and nAg caused no adverse effects, but the presence of 20 g of nZnO/L and 0.65 g of nAg/L significantly inhibited microbial growth. Statistical evidence showed that nAg was significantly more toxic compared to nZnO, but there was an insignificant difference in toxicity between microbial communities and pH variations. A significant decrease in the removal of COD by microbial populations was observed in the presence of NMs with a moderate correlation of r = 0.3 to r = 0.7 at all pH levels. It was evident that there was a physical interaction between commercial NMs and target wastewater microbial communities; although not quantitatively assessed, cell morphology and cell death were observed. Such phenomena suggest the high resilience of the microbial community, but it is the accumulation of NMs that will have adverse effects on the performance in terms of COD removal.

Keywords: bacteria, biological treatment, chemical oxygen demand (COD) and nanomaterials, consortium, pH, protozoan

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Authors: Hye Jin Choi, Mirim Jin, Jeong June Choi

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Green tea, which is one of the most popular of tea, contains various ingredients that help health. Epigallocatechin gallate (EGCG) is one of the main active polyphenolic compound possessing diverse biologically beneficial effects such as anti-oxidation, anti-cancer founding in green tea. This study was performed to investigate the anti-diabetic effect of high-purity EGCG ( > 98%) in a spontaneous diabetic mellitus animal model, db/db mouse. Four-week-old male db/db mice, which was induced to diabetic mellitus by the high-fat diet, were orally administered with high-purity EGCG (10, 50 and 100 mg/kg) for 4 weeks. Daily weight and diet efficiency were examined, and blood glucose level was assessed once a week. After 4 weeks of EGCG administration, fasting blood glucose level was measured. Then, the mice were sacrificed and total abdominal fat was sampled to examine the change in fat weight. Plasma was separated from the blood and the levels of aspartate amino-transferase (ALT) and alanine amino-transferase (AST) were investigated. As results, blood glucose and body weight were significantly decreased by EGCG treatment compared to the control group. Also, the amount of abdominal fat was down-regulated by EGCG. However, ALT and AST levels, which are indicators of liver function, were similar to those of control group. Taken together, our study suggests that high purity EGCG is capable of treating diabetes mellitus based in db / db mice with safety and has a potent to develop a therapeutics for metabolic disorders. This work was supported by Korea Institute of Planning and Evaluation for Technology in Food, Agriculture, Forestry (IPET) through High Value-added Food Technology Development Program, funded by Ministry of Agriculture, Food and Rural Affairs (MAFRA) (317034-03-2-HD030)

Keywords: anti-diabetic effect, db/db mouse, diabetes mellitus, green tea, epigallocatechin gallate

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Authors: M. Zeitoun, K. Abdallah, M. Rashwan

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Introduction: A growing body of evidence indicates that apelin, a relatively recent member of the adipokines family, has a potential anti-atherogenic effect. An association between low serum apelin state and coronary artery disease (CAD) was previously reported; however, the relationship between apelin and the atherosclerotic burden was unclear. Objectives: Our aim was to explore the correlation of serum apelin level with coronary calcium score (CCS) as a quantitative marker of coronary atherosclerosis. Methods: This observational cross-sectional study enrolled 100 consecutive subjects referred for cardiac multi-detector computed tomography (MDCT) for assessment of CAD (mean age 54 ± 9.7 years, 51 male and 49 females). Clinical parameters, glycemic and lipid profile, high sensitivity CRP (hsCRP), homeostasis model assessment of insulin resistance (HOMA-IR), serum creatinine and complete blood count were assessed. Serum apelin levels were determined using a commercially available Enzyme Immunoassay (EIA) Kit. High-resolution non-contrast CT images were acquired by a 64-raw MDCT and CCS was calculated using the Agatston scoring method. Results: Forty-three percent of the studied subjects had positive coronary artery calcification (CAC). The mean CCS was 79 ± 196.5 Agatston units. Subjects with detectable CAC had significantly higher fasting plasma glucose, HbA1c, and WBCs count than subjects without detectable CAC (p < 0.05). Most importantly, subjects with detectable CAC had significantly lower serum apelin level than subjects without CAC (1.3 ± 0.4 ng/ml vs. 2.8 ± 0.6 ng/ml, p < 0.001). In addition, there was a statistically significant inverse correlation between serum apelin levels and CCS (r = 0.591, p < 0.001); on multivariate analysis this correlation was found to be independent of traditional cardiovascular risk factors and hs-CRP. Conclusion:To the best of our knowledge, this is the first report of an independent association between apelin and CCS in patients with suspected CAD. Apelin emerges as a possible novel biomarker for CAD, but this result remains to be proved prospectively.

Keywords: HbA1c, apelin, adipokines, coronary calcium score (CCS), coronary artery disease (CAD)

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Authors: Irena Baranowska-Bosiacka, Mateusz Bosiacki, Patrycja Kupnicka, Anna Lubkowska, Dariusz Chlubek

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Physical activity and a balanced diet are among the key factors of "healthy ageing". Physical effort, including swimming in cold water (including bathing in natural water reservoirs), is widely recognized as a hardening factor, with a positive effect on the mental and physical health. At the same time, there is little scientific evidence to verify this hypothesis. In the literature to date, it is possible to obtain data on the impact of these factors on selected physiological and biochemical parameters of the blood, at the same time there are no results of research on the effect of immersing in cold water on mineral metabolism, especially bones, hence it seems important to perform such an analysis in relation to the key elements such as calcium (Ca), magnesium (Mg) and phosphorus (P). Taking the above into account, a hypothesis was put forward about the possibility of a positive effect of exercise in cold water on mineral metabolism and bone density in aging rats. The aim of the study was to evaluate the effect of an 8-week swimming training on mineral metabolism and bone density in aging rats in response to exercise in cold water (5oC) in comparison to swimming in thermal comfort (36oC) and sedentary (control) rats of both sexes. The examination of the concentration of the examined elements in the bones was carried out using inductively coupled plasma atomic emission spectrometry (ICP-OES). The mineral density of the femurs of the rats was measured using the Hologic Horizon DEXA System® densitometer. The results of our study showed that swimming in cold water affects bone mineral metabolism in aging rats by changing the Ca, Mg, P concentration and at the same time increasing their bone density. In males, a decrease in Mg concentration and no changes in bone density were observed. In the light of the research results, it seems that swimming in cold water may be a factor that positively modifies the bone aging process by improving the mechanisms affecting their density.

Keywords: swimming in cold water, adaptation to cold water, bone mineral metabolism, aging

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Authors: Milton Manyangadze, Joseph Govha, T. Bala Narsaiah, Ch. Shilpa Chakra

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The availability and access to fresh water is today a serious global challenge. This has been a direct result of factors such as the current rapid industrialization and industrial growth, persistent droughts in some parts of the world, especially in the sub-Saharan Africa as well as population growth. Growth of the chemical processing industry has also seen an increase in the levels of pollutants in our water bodies which include heavy metals among others. Heavy metals are known to be dangerous to both human and aquatic life. As such, they have been linked to several diseases. This is mainly because they are highly toxic. They are also known to be bio accumulative and non-biodegradable. Lead for example, has been linked to a number of health problems which include damage of vital internal body systems like the nervous and reproductive system as well as the kidneys. From this background therefore, the removal of the toxic heavy metal, Pb2+ from waste water was investigated using nano silica hollow spheres (NSHS) as the adsorbent. Synthesis of NSHS was done using a three-stage process in which CaCO3 nanoparticles were initially prepared as a template. This was followed by treatment of the formed oxide particles with NaSiO3 to give a nanocomposite. Finally, the template was destroyed using 2.0M HCl to give NSHS. Characterization of the nanoparticles was done using analytical techniques like XRD, SEM, and TGA. For the adsorption process, both thermodynamic and equilibrium studies were carried out. Thermodynamic studies were carried out and the Gibbs free energy, Enthalpy and Entropy of the adsorption process were determined. The results revealed that the adsorption process was both endothermic and spontaneous. Equilibrium studies were also carried out in which the Langmuir and Freundlich isotherms were tested. The results showed that the Langmuir model best described the adsorption equilibrium.

Keywords: characterization, endothermic, equilibrium studies, Freundlich, Langmuir, nanoparticles, thermodynamic studies

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Authors: Soad Ali Yehia, Mohamed Shafik El-Ridi, Mina Ibrahim Tadros, Nolwa Gamal El-Sherif

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Fexofenadine hydrochloride (FXD) is a slightly soluble, bitter-tasting, drug having an oral bioavailability of 35%. The maximum plasma concentration is reached 2.6 hours (Tmax) post-dose. The current work aimed to develop taste-masked FXD orodispersible tablets (ODTs) to increase extent of drug absorption and reduce Tmax. Taste masking was achieved via solid dispersion (SD) with chitosan (CS) or sodium alginate (ALG). FT-IR, DSC and XRD were performed to identify physicochemical interactions and FXD crystallinity. Taste-masked FXD-ODTs were developed via addition of superdisintegrants (crosscarmelose sodium or sodium starch glycolate, 5% and 10%, w/w) or sublimable agents (camphor, menthol or thymol; 10% and 20%, w/w) to FXD-SDs. ODTs were evaluated for weight variation, drug-content, friability, wetting time, disintegration time and drug release. Camphor-based (20%, w/w) FXD-ODT (F12) was optimized (F23) by incorporation of a more hydrophilic lubricant, sodium stearyl fumarate (Pruv®). The topography of the latter formula was examined via scanning electron microscopy (SEM). The in vivo estimation of FXD pharmacokinetics, relative to Allegra® tablets, was evaluated in healthy human volunteers. Based on the gustatory sensation test in healthy volunteers, FXD:CS (1:1) and FXD:ALG (1:0.5) SDs were selected. Taste-masked FXD-ODTs had appropriate physicochemical properties and showed short wetting and disintegration times. Drug release profiles of F23 and phenylalanine-containing Allegra® ODT were similar (f2 = 96) showing a complete release in two minutes. SEM micrographs revealed pores following camphor sublimation. Compared to Allegra® tablets, pharmacokinetic studies in healthy volunteers proved F23 ability to increase extent of FXD absorption (14%) and reduce Tmax to 1.83 h.

Keywords: fexofenadine hydrochloride, taste masking, chitosan, orodispersible

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Authors: Samy S. Eleawa, Mahmoud A. Alkhateeb, Fahaid H. Alhashem, Ismaeel bin-Jaliah, Hussein F. Sakr, Hesham M. Elrefaey, Abbas O. Elkarib, Mohammad A. Haidara, Abdullah S. Shatoor, Mohammad A. Khalil

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This effect of Resveratrol (RES) against CdCl2- induced toxicity in the rat testes was investigated. Seven experimental groups of adult male rats were formulated as follows: A) Controls + NS, B) Control+ vehicle (saline solution of hydroxypropyl cyclodextrin), C) RES treated, D) CdCl2 +NS, E) CdCl2+ vehicle, F) RES followed by CdCl2 and M) CdCl2 followed by RES. At the end of the protocol, serum levels of FSH, LH, and testosterone were measured in all groups. Testicular levels of TBARS and Super Oxide Dismutase (SOD) activity were also measured. Epidydidimal semen analysis was performed and testicular expression of Bcl-2, p53 and Bax were assessed by RT-PCR. Also, histopathological changes of testes were examined microscopically and described. Pre and Post administration of RES in cadmium chloride-intoxicated rats improved semen parameters including count, motility, daily sperm production and morphology, increased serum concentrations of gonadotropins and testosterone, decreased testicular lipid peroxidation and increased SOD activity. Not only RES attenuated cadmium chloride induced testicular histopathology but was also able to protect against the onset of cadmium chloride testicular toxicity. Cadmium chloride downregulated the anti-apoptotic gene Bcl2 and upregulated the expression of both pro-apoptotic genes p53 and Bax. Resveratrol protected from and partially reversed cadmium chloride testicular via upregulation of Bcl2 and down regulation of p53 and Bax gene expression. Antioxidant activity of RES protects against cadmium chloride testicular toxicity and partially reverses its effect via upregulation of BCl2 and downregulation of p53 and Bax expression. These findings have far reaching implications on subfertility and impotency frequently seen in hypertensive as well as metabolic syndrome patients.

Keywords: resveratrol, cadmium, infertility, sperm, testis, metabolic syndrome

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Authors: Sonia Barbouchi, Meriem Samcha

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Scale deposition during water injection into aquifer of oil reservoirs is a serious problem experienced in the oil production industry. One of the primary causes of scale formation and injection well plugging is mixing two waters which are incompatible. Considered individually, the waters may be quite stable at system conditions and present no scale problems. However, once they are mixed, reactions between ions dissolved in the individual waters may form insoluble products. The purpose of this study is to identify the causes of well plugging in a southern Tunisian oilfield, where fresh water has been injected into the producing wells to counteract the salinity of the formation waters and inhibit the deposition of halite. X-ray diffraction (XRD) mineralogical analysis has been carried out on scale samples collected from the blocked well. Two samples collected from both formation water and injected water were analysed using inductively coupled plasma atomic emission spectroscopy, ion chromatography and other standard laboratory techniques. The results of complete waters analysis were the typical input parameters, to determine scaling tendency. Saturation indices values related to CaCO3, CaSO4, BaSO4 and SrSO4 scales were calculated for the water mixtures at different share, under various conditions of temperature, using a computerized scale prediction model. The compatibility study results showed that mixing the two waters tends to increase the probability of barite deposition. XRD analysis confirmed the compatibility study results, since it proved that the analysed deposits consisted predominantly of barite with minor galena. At the studied temperatures conditions, the tendency for barite scale is significantly increasing with the increase of fresh water share in the mixture. The future scale inhibition and removal strategies to be implemented in the concerned oilfield are being derived in a large part from the results of the present study.

Keywords: compatibility study, produced water, scaling, water injection

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Authors: A. A. Adebayo, O. Osibanjo

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Informal electronic waste (e-waste) processing is a crude method of recycling, which is on the increase in Nigeria. The release of hazardous substances such as heavy metals (HMs) into the environment during informal e-waste processing has been a major concern. However, there is insufficient information on environmental contamination from e-waste recycling, associated ecological risk in Alaba International Market, a major electronic market in Lagos, Nigeria. The aims of this study were to determine the levels of HMs in soil, resulting from the e-waste recycling; and also assess associated ecological risks in Alaba international market. Samples of soils (334) were randomly collected seasonally for three years from fourteen selected e-waste activity points and two control sites. The samples were digested using standard methods and HMs analysed by inductive coupled plasma optical emission. Ecological risk was estimated using Ecological Risk index (ER), Potential Ecological Risk index (RI), Index of geoaccumulation (Igeo), Contamination factor (Cf) and degree of contamination factor (Cdeg). The concentrations range of HMs (mg/kg) in soil were: 16.7-11200.0 (Pb); 14.3-22600.0 (Cu); 1.90-6280.0 (Ni), 39.5-4570.0 (Zn); 0.79-12300.0 (Sn); 0.02-138.0 (Cd); 12.7-1710.0 (Ba); 0.18-131.0 (Cr); 0.07-28.0 (V), while As was below detection limit. Concentrations range in control soils were 1.36-9.70 (Pb), 2.06-7.60 (Cu), 1.25-5.11 (Ni), 3.62-15.9 (Zn), BDL-0.56 (Sn), BDL-0.01 (Cd), 14.6-47.6 (Ba), 0.21–12.2 (Cr) and 0.22-22.2 (V). The trend in ecological risk index was in the order Cu > Pb > Ni > Zn > Cr > Cd > Ba > V. The potential ecological risk index with respect to informal e-waste activities were: burning > dismantling > disposal > stockpiling. The index of geo accumulation indices revealed that soils were extremely polluted with Cd, Cu, Pb, Zn and Ni. The contamination factor indicated that 93% of the studied areas have very high contamination status for Pb, Cu, Ba, Sn and Co while Cr and Cd were in the moderately contaminated status. The degree of contamination decreased in the order of Sn > Cu > Pb >> Zn > Ba > Co > Ni > V > Cr > Cd. Heavy metal contamination of Alaba international market environment resulting from informal e-waste processing was established. Proper management of e-waste and remediation of the market environment are recommended to minimize the ecological risks.

Keywords: Alaba international market, ecological risk, electronic waste, heavy metal contamination

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Authors: Mohammad Karimi, Magnus Heurlin, Lars Samuelson, Magnus Borgstrom, Hakan Pettersson

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Nanowire semiconductors are promising candidates for optoelectronic applications such as solar cells, photodetectors and lasers due to their quasi-1D geometry and large surface to volume ratio. The functional wavelength range of NW-based detectors is typically limited to the visible/near-infrared region. In this work, we present electrical and optical properties of IR photodetectors based on large square millimeter ensembles (>1million) of vertically processed semiconductor heterostructure nanowires (NWs) grown on InP substrates which operate in longer wavelengths. InP NWs comprising single or multiple (20) InAs/InAsP QDics axially embedded in an n-i-n geometry, have been grown on InP substrates using metal organic vapor phase epitaxy (MOVPE). The NWs are contacted in vertical direction by atomic layer deposition (ALD) deposition of 50 nm SiO2 as an insulating layer followed by sputtering of indium tin oxide (ITO) and evaporation of Ti and Au as top contact layer. In order to extend the sensitivity range to the mid-wavelength and long-wavelength regions, the intersubband transition within conduction band of InAsP QDisc is suggested. We present first experimental indications of intersubband photocurrent in NW geometry and discuss important design parameters for realization of intersubband detectors. Key advantages with the proposed design include large degree of freedom in choice of materials compositions, possible enhanced optical resonance effects due to periodically ordered NW arrays and the compatibility with silicon substrates. We believe that the proposed detector design offers the route towards monolithic integration of compact and sensitive III-V NW long wavelength detectors with Si technology.

Keywords: intersubband photodetector, infrared, nanowire, quantum disc

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Authors: Sellidj Abdelaziz, Lebaili Soltane

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A cobalt-based alloy type Co-Cr-Ni-WC was deposited by plasma transferred arc projection (PTA) on a stainless steel valve. The alloy is characterized at the equilibrium by a solid solution Co (γ) mainly dendritic, and eutectic carbides M₇C₃ and ηM₆C. At the deposit/substrate interface, this microstructure is modified by the fast cooling mode of the alloy when applied in the liquid state on the relatively cold steel substrate. The structure formed in this case is heterogeneous and metastable phases can occur and evolve over temperature service. Coating properties and reliability are directly related to microstructures formed during deposition. We were interested more particularly in this microstructure formed during the solidification of the deposit in the region of the interface joining the soldered couple and its evolution during cyclic heat treatments at temperatures similar to those of the thermal environment of the valve. The characterization was carried out by SEM-EDS microprobe CAMECA, XRD, and micro hardness profiles. The deposit obtained has a linear and regular appearance that is free of cracks and with little porosity. The morphology of the microstructure represents solidification stages that are relatively fast with a temperature gradient high at the beginning of the interface by forming a plane front solid solution Co (γ). It gradually changes with the decreasing temperature gradient by getting farther from the junction towards the outer limit of the deposit. The matrix takes the forms: cellular, mixed (cells and dendrites) and dendritic. Dendritic growth is done according to primary ramifications in the direction of the heat removal which takes place in the direction perpendicular to the interface, towards the external surface of the deposit, following secondary and tertiary undeveloped arms. The eutectic carbides M₇C₃ and ηM₆C formed are very thin and are located in the intercellular and interdendritic spaces of the solid solution Co (γ).

Keywords: Co-Ni-Cr-W-C alloy, solid deposit, microstructure, carbides, cyclic heat treatment

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Authors: Amir Khaleghipour, Amirhossein Moghanian, Elhamalsadat Ghaffari

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Modified bioactive glass has been considered as a promising multifunctional candidate in bone repair and regeneration due to its attractive properties. The present study mainly aims to evaluate how the individual substitution of lithium (L-BG) and magnesium (M-BG) for calcium can affect the in vitro bioactivity of sol-gel derived substituted 58S bioactive glass (BG); and to present one composition in both of the 60SiO₂–(36-x)CaO–4P₂O₅–(x)Li₂O and 60SiO₂–(36-x)CaO–4P₂O₅–(x)MgO quaternary systems (where x= 0, 5, 10 mol.%) with improved biocompatibility, enhanced alkaline phosphatase (ALP) activity, and the most efficient antibacterial activity against methicillin-resistant Staphylococcus aureus bacteria. To address these aims, and study the effect of CaO/Li₂O and CaO/MgO substitution up to 10 mol % in 58S-BGs, the samples were characterized by X-ray diffraction, Fourier transform infrared spectroscopy, inductively coupled plasma atomic emission spectrometry and scanning electron microscopy after immersion in simulated body fluid up to 14 days. Results indicated that substitution of either CaO/ Li₂O and CaO/ MgO had a retarding effect on in vitro hydroxyapatite (HA) formation due to the lower supersaturation degree for nucleation of HA compared with 58s-BG. Meanwhile, magnesium had a more pronounced effect. The 3-(4, 5dimethylthiazol-2-yl)-2,5-diphenyltetrazolium bromide (MTT) and alkaline phosphatase (ALP) assays showed that both substitutions of CaO/ Li₂O and CaO/ MgO up to 5mol % in 58s-BGs led to increased biocompatibility and stimulated proliferation of the pre-osteoblast MC3T3 cells with respect to the control. On the other hand, substitution of either Li or Mg for Ca in the 58s BG composition resulted in improved bactericidal efficiency against MRSA bacteria. Taken together, sample 58s-BG with 5 mol % CaO/Li₂O substitution (BG-5L) was considered as a multifunctional biomaterial in bone repair/regeneration with improved biocompatibility, enhanced ALP activity as well enhanced antibacterial efficiency against methicillin-resistant Staphylococcus aureus (MRSA) bacteria among all of the synthesized L-BGs and M-BGs.

Keywords: alkaline, alkaline earth, bioactivity, biomedical applications, sol-gel processes

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Authors: Vaiyapuri Subbarayn Periasamy, Jegan Athinarayanan, Ali A. Alshatwi

Abstract:

The widespread use of Titanium oxide nanoparticles (TiO2-NPs), now are found with different physic-chemical properties (size, shape, chemical properties, agglomeration, etc.) in many processed foods, agricultural chemicals, biomedical products, food packaging and food contact materials, personal care products, and other consumer products used in daily life. Growing evidences have been highlighted that there are risks of physico-chemical properties dependent toxicity with special attention to “TiO2-NPs and human immune system”. Unfortunately, agglomeration and aggregation have frequently been ignored in immuno-toxicological studies, even though agglomeration and aggregation would be expected to affect nanotoxicity since it changes the size, shape, surface area, and other properties of the TiO2-NPs. In this present investigation, we assessed the immune toxic effect of TiO2-NPs on human immune cells Total WBC including Lymphocytes (T cells (CD3+), T helper cells (CD3+, CD4+), Suppressor/cytotoxic T cells (CD3+/CD8+) and NK cells (CD3-/CD16+ and CD56+), Monocytes (CD14+, CD3-) and B lymphocytes (CD19+, CD3-) in order to find the immunological response (IL1A, IL1B, IL2 IL-4, IL5 IL-6, IL-10, IL-12, IL-13, IFN-γ, TGF-β, and TNF-a) and redox gene regulation (TNF, p53, BCl-2, CAT, GSTA4, TNF, CYP1A, POR, SOD1, GSTM3, GPX1, and GSR1)-linking physicochemical properties with special reference to agglomeration of TiO2-NPs. Our findings suggest that TiO2-NPs altered cytokine production, enhanced phagocytic indexing, metabolic stress through specific immune regulatory- genes expression in different WBC subsets and may contribute to pro-inflammatory response. Although TiO2-NPs have great advantages in the personal care products, biomedical, food and agricultural products, its chronic and acute immune-toxicity still need to be assessed carefully with special reference to food and environmental safety.

Keywords: TiO2 nanoparticles, oxidative stress, cytokine, human immune cells

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Authors: Tanira Kingi, Oscar Montes Oca, Reina Tamepo

Abstract:

The introduction of the Climate Change Response (Zero Carbon) Amendment Act (2019) and the National Policy Statement for Freshwater Management (2020) both contain underpinning statements that refer to the principles of the Treaty of Waitangi and cultural concepts of stewardship and environmental protection. Maori interests in New Zealand’s agricultural, forestry, fishing and horticultural sectors are significant. The organizations that manage these investments do so on behalf of extended family groups that hold inherited interests based on genealogical connections (whakapapa) to particular tribal units (iwi and hapu) and areas of land (whenua) and freshwater bodies (wai). This paper draws on the findings of current research programmes funded by the New Zealand Agricultural Greenhouse Gas Research Centre (NZAGRC) and the Our Land & Water National Science Challenge (OLW NSC) to understand the impact of cultural knowledge and imperatives on agricultural GHG and freshwater mitigation and land-use change decisions. In particular, the research outlines mitigation and land-use change scenario decision support frameworks that model changes in emissions profiles (reductions in biogenic methane, nitrous oxide and nutrient emissions to freshwater) of agricultural and forestry production systems along with impacts on key economic indicators and socio-cultural factors. The paper also assesses the effectiveness of newly introduced partnership arrangements between Maori groups/organizations and key government agencies on policy co-design and implementation, and in particular, decisions to adopt mitigation practices and to diversify land use.

Keywords: co-design and implementation of environmental policy, indigenous environmental knowledge, Māori land tenure and agribusiness, mitigation and land use change decision support frameworks

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Authors: Elitsa Kolentsova, Dimitar Dimitrov, Vasko Idakiev, Tatyana Tabakova, Krasimir Ivanov

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Formaldehyde production by selective oxidation of methanol is an important industrial process. The main by-products in the waste gas are CO and dimethyl ether (DME). The idea of this study is to combine the advantages of both Cu-Mn and Cu-Co catalytic systems by obtaining a new mixed Cu-Mn-Co catalyst with high activity and selectivity at the simultaneous oxidation of CO, methanol, and DME. Two basic Cu-Mn samples with high activity were selected for further investigation: (i) manganese-rich Cu-Mn/γ–Al2O3 catalyst with Cu/Mn molar ratio 1:5 and (ii) copper-rich Cu-Mn/γ-Al2O3 catalyst with Cu/Mn molar ratio 2:1. Manganese in these samples was replaced by cobalt in the whole concentration region, and catalytic properties were determined. The results show a general trend of decreasing the activity toward DME oxidation and increasing the activity toward CO and methanol oxidation with the increase of cobalt up to 60% for both groups of catalyst. This general trend, however, contains specific features, depending on the composition of the catalyst and the nature of the oxidized gas. The catalytic activity of the sample with Cu/(Mn+Co) molar ratio of 2:1 is gradually changed with increasing the cobalt content. The activity of the sample with Cu/(Mn+Co) molar ratio of 1: 5 passes through a maximum at 60% manganese replacement by cobalt, probably due to the formation of highly dispersed Co-based spinel structures (Co3O4 and/or MnCo2O4). In conclusion, the present study demonstrates that the Cu-Mn-Co/γ–alumina supported catalysts have enhanced activity toward CO, methanol and DME oxidation. Cu/(Mn+Co) molar ratio 1:5 and Co/Mn molar ratio 1.5 in the active component can ensure successful oxidation of CO, CH3OH and DME. The active component of the mixed Cu-Mn-Co/γ–alumina catalysts consists of at least six compounds - CuO, Co3O4, MnO2, Cu1.5Mn1.5O4, MnCo2O4 and CuCo2O4, depending on the Cu/Mn/Co molar ratio. Chemical composition strongly influences catalytic properties, this effect being quite variable with regards to the different processes.

Keywords: Cu-Mn-Co catalysts, oxidation, carbon oxide, VOCs

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Authors: Biswajit Pal, Amit Mallik, Anil K. Barik

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Current years have witnessed a phenomenal growth in the research on the rare earth-doped transparent host materials, the essential components in optoelectronics that meet up the increasing demand for fabrication of high quality optical devices especially in telecommunication system. The combination of low phonon energy (because of fluoride environment) and high chemical durability with superior mechanical stability (due to oxide environment) makes the oxyfluoride glass–ceramics the promising and useful materials in optoelectronics. The present work reports on the undoped and doped (1 mol% Pr2O3) glass ceramics of composition 16.52 Al2O3•1.5AlF3• 12.65LaF3•4.33Na2O•64.85 SiO2 (mol%), prepared by melting technique initially that follows annealation at 450 ºC for 1 h. The glass samples so obtained were heat treated at constant 600 ºC with a variation in heat treatment schedule (10- 80 h). TEM techniques were employed to structurally characterize the glass samples. Pr2O3 affects the phase separation in the glass and delays the onset of crystallization in the glass ceramic. The modified crystallization mechanism is established from the analysis of advanced STEM/EDXS results. The phase separated droplets after annealing turn into 10-20 nm of LaF3 nano crystals those upon scrutiny are found to be dotted with the doped Pr3+ ions within the crystals themselves. The EDXS results also suggest that the inner LaF3 crystal core is swallowed by an Al enriched layer that follows a Si enriched surrounding shell as the outer core. This greatly increases the viscosity in the periphery of the crystals that restricts further crystal growth to account for the formation of nano sized crystals.

Keywords: advanced STEM/EDXS, crystallization mechanism, nano crystals, pr3+ ion doped glass and glass ceramic, structural characterization

Procedia PDF Downloads 171

Authors: Magdalena Bury-Kaminska, Aneta Szudy-Szczyrek, Aleksandra Nowaczynska, Olga Jankowska-Lecka, Marek Hus, Klaudia Kot

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Introduction: The aim of the research was to determine the changes in cognitive functioning in patients with plasma cell myeloma by comparing patients’ state before the treatment and during chemotherapy as well as to determine the biological factors that can be used to predict patients’ cognitive state. Methods: The patients underwent the research procedure twice: before chemotherapy and after 4-6 treatment cycles. A psychological test and measurement of the following biological variables were carried out: TNF-α (tumor necrosis factor), IL-6 (interleukin 6), IL-10 (interleukin 10), BDNF (brain-derived neurotrophic factor). The following research methods were implemented: the Montreal Cognitive Assessment (MoCA), Battery of Tests for Assessing Cognitive Functions PU1, experimental and clinical trials based on the Choynowski’s Memory Scale, Stroop Color-Word Interference Test (SCWT), depression measurement questionnaire. Results: The analysis of the research showed better cognitive functions of patients during chemotherapy in comparison to the phase before it. Moreover, neurotrophin BDNF allows to predict the level of selected cognitive functions (semantic fluency and execution control) already at the diagnosis stage. After 4-6 cycles, it is also possible to draw conclusions concerning the extent of working memory based on the level of BDNF. Cytokine TNF-α allows us to predict the level of letter fluency during anti-cancer treatment. Conclusions: It is possible to presume that BDNF has a protective influence on patients’ cognitive functions and working memory and that cytokine TNF-α co-occurs with a diminished execution control and better material grouping in terms of phonological fluency. Acknowledgment: This work was funded by the National Science Center in Poland [grant no. 2017/27/N/HS6/02057.

Keywords: chemobrain, cognitive impairment, non−central nervous system cancers, hematologic diseases

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Authors: Ismail I. Abo-Ghanema, Faheim E. Wehaish, Rasha M. Saleh , Walaa F. Awadin, Mohamed F. Elshal

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The antidiabetic activity of myrrh and ginseng ethanolic extracts were investigated in streptozotocin (STZ)-induced diabetic rats. Thirty male albino rats were divided into five groups, each consisted of six rats. The first group (G1) is the negative control that was fed basal diet, the second group (G2) was injected with STZ and received no treatment, the third group (G3) injected with STZ and received metformin (50 mg/kg, b.wt) as standard anti-diabetic drug, the fourth group (G4) injected with STZ and ginseng (50 mg/kg, b.wt), the fifth group (G5) injected with STZ and received myrrh (500 mg/kg, b.wt). As compared with G1-group, STZ injection increased blood concentrations of glucose (6.2 fold), glycated hemoglobin (HbA1c) (2.51 fold), aspartateaminotransferase (AST), and alanine aminotransferase (ALT) (2.64, 4.60 fold respectively), creatinine (2.91 fold), cholesterol (1.79 fold), triglycerides (2.06 fold), low density lipoprotein-cholesterol (LDL) (2.92 fold), nitric oxide (NO) (20.18 fold), and malondialdehyde (MDA) (2.25 fold), whereas it decreased blood insulin (0.40 fold), albumin (0.60 fold), high density lipoprotein-cholesterol (HDL) (0.33 fold), and reduced glutathione (GSH) (0.49 fold). Vascular permeability index (VPI as measured by Evan's Blue; EB extravasations test) was significantly increased in the skin of diabetic animals (9.6 fold) when compared with the G1-group. In addition, histological alterations in liver, pancreas, kidneys and heart were observed. After 4 weeks of treatment, rats in G4 and G5 showed significant corrections in the all measured parameters and indices. In conclusions, the ethanolic extracts of ginseng and myrrh exhibited promising and safe anti-diabetic activity especially on peripheral circulation as manifested by decreased vascular permeability and improved histopathological alterations of examined organs and insulin secretion. Hence, it may be pursued for their clinical usefulness in the management of diabetes mellitus (DM) and associated vascular complications.

Keywords: diabetic rats, peripheral circulation, natural plants, myrrh, ginseng

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Authors: Vishnu Varthan Vaithiyalingamjagannathan, M. N. Sathishkumar, K. S. Lakhsmi, D. Satheeshkumar, Srividyaammayappanrajam

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Background:Naringenin, aglycone flavonoid possess certain activities like anti-oxidant, anti-estrogenic, anti-diabetic, cardioprotective, anti-obesity,anti-inflammatory, hepatoprotective and also have anti-cancer characteristics like carcinogenic inactivation, cell cycle arrest, anti-proliferation, apoptosis, anti-angiogenesis and enhances anti-oxidant activity. Methodology:The inhibitory effect of Naringenin in lung tumor progression estimated with adenocarcinoma (A549) cell lines (in vitro) and C57BL/6 mice injected with 5 X 106A549 cell lines (in vivo) in a tri-dose manner (Naringenin 100mg/kg,150mg/kg, and 200mg/kg) compared with standard chemotherapy drug cisplatin (7mg/kg). Results:The results of the present study revealed a dose-dependent activity in Naringenin and combination with cisplatin at a higher dose which showed decreased tumor progression in mice. In vitro studies carried out for estimation of cell survival and Nitric Oxide (NO) level, shows dose dependent action of Naringenin with IC50 value of 42µg/ml. In vivo studies were carried out in C57BL/6 mice. Naringenin satisfied the condition of an anti-cancer molecule with its characteristics in fragmentation assay, Zymography assay, anti-oxidant, and myeloperoxidase studies, than cisplatin which failed in anti-oxidant and myeloperoxidase effect. Both in vitro and in vivo establishes dose dependent decrease in NO levels. But whereas, Naringenin showed adverse results in Matrix Metalloproteinase (MMP) enzymatic levels with increase in dose levels. Conclusion:From the present study, Naringenin could suppress the lung tumor progression when given individually and also in combinatorial with standard chemotherapy drug.

Keywords: naringenin, in vitro, cell line, anticancer

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