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21.
Advanced classes of modern application require new generation of versatile solar cells showcasing extreme mechanical resilience, large‐scale, low cost, and excellent power conversion efficiency. Conventional crystalline silicon‐based solar cells offer one of the most highly efficient power sources, but a key challenge remains to attain mechanical resilience while preserving electrical performance. A complementary metal oxide semiconductor‐based integration strategy where corrugation architecture enables ultraflexible and low‐cost solar cell modules from bulk monocrystalline large‐scale (127 × 127 cm2) silicon solar wafers with a 17% power conversion efficiency. This periodic corrugated array benefits from an interchangeable solar cell segmentation scheme which preserves the active silicon thickness of 240 µm and achieves flexibility via interdigitated back contacts. These cells can reversibly withstand high mechanical stress and can be deformed to zigzag and bifacial modules. These corrugation silicon‐based solar cells offer ultraflexibility with high stability over 1000 bending cycles including convex and concave bending to broaden the application spectrum. Finally, the smallest bending radius of curvature lower than 140 µm of the back contacts is shown that carries the solar cells segments.  相似文献   
22.
Spexin (SPX) is a novel biomarker abundantly expressed in several animal and human tissues implicated in food intake and glucose control, respectively. As new roles for SPX are emerging, the present study explored for the first time, the associations of SPX to several cardiometabolic indices and inflammatory markers in pregnant women, a demographic not yet investigated with respect to SPX. A total of 117 Saudi women subdivided to those with gestational diabetes mellitus (GDM) (N?=?63) and those without (N?=?54) were included in this cross-sectional study. Anthropometry, glycemic, lipid, vitamin D, adipocytokines and inflammatory markers were measured consecutively at baseline and after the 2nd and 3rd trimesters. Age- and BMI adjusted comparisons revealed that levels of SPX were not significantly different in pregnant women with and without GDM. In all subjects, circulating levels of SPX showed modest associations with glucose (R?=?0.18; p?=?.08) and HOMA β (R?=??0.19; p?=?.09) as well as significant positive associations with total cholesterol (R?=?0.25; p?=?.02), LDL-cholesterol (R?=?0.25; p?=?.02), 25(OH)D (R?=?0.22; p?=?.04), albumin (R?=?0.30; p?<?.01) and IL1β (R?=?0.41; p?<?.01). Stepwise regression analysis also suggested that IL1β, leptin and albumin were the significant predictors of SPX. In summary, SPX levels modestly affect glucose and insulin sensitivity in pregnant women but is not associated with GDM and obesity. The significant association of SPX to ILβ warrants further investigation as to the role of SPX in immune modulation.  相似文献   
23.
Most of the studies investigated the effects of nutrient-based fertilizers on olive fruits and oil quality; few studies have been interested in the modification of the chemical composition of olive leaves in response to fertilization. Thus, the current study aims to examine the effects of foliar fertilization on the mineral profile of olive leaves as well as the concentrations of chlorophyll, antioxidants (phenolic compounds) and carbohydrates. Experimentation consists of the annual application of six treatments during two successive growing seasons (2009–2010): TC (untreated trees), P1 (nitrogen-based fertilizer), P2 (contains boron, magnesium and manganese), P3 (phosphorus and potassium based fertilizer), P4 (rich in calcium and phosphorus), T5 (P1 and P2 application) and T6 (P1, P2, P3 and P4 application). At the end of the experiment, mineral analysis of olive leaves showed an increase in the concentrations of most nutrients which induced changes in biochemical composition: an increase of chlorophyll content, a reduction of total phenols and oleuropein concentrations coupled with an increase of hydroxytyrosol level. Moreover, an increase of total sugar content and most individual sugars, principally translocated forms of sugars (mannitol, sucrose and raffinose), was also observed. The accumulation of these key physiological parameters by foliar fertilization suggests an improvement of physiological performance and photosynthetic capacity of olive trees. Moreover, from a biological point of view, the results of the study revealed the possibility to improve plants of medicinal interest by enhancing the accumulation of some bio-active compounds, such as hydroxytyrosol and mannitol, via foliar nutrient supply.  相似文献   
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Sea cucumbers are benthic marine invertebrates with immense ecological and commercial value. Processed sea cucumbers known as “Beche-de-mer” are a delicacy in southeast Asian countries with an ever-increasing demand depleting wild stocks on a global scale. Aquaculture techniques are well developed for commercially important species (e.g. Holothuria scabra) to aid in conservation and trade. In the Arabian Peninsula and Iran, where the major land mass is surrounded by marginal seas (Arabian Gulf, Gulf of Oman, Arabian Sea, Gulf of Aden, and Red Sea), studies on sea cucumbers are rather limited and its economic value is underestimated. Historical and current research trends indicate impoverished diversity (82 species) due to environmental extremes. Artisanal fisheries exist for the sea cucumbers of Iran, Oman, and Saudi Arabia, with Yemen and United Arab Emirates (UAE) playing a key role in collection and export to Asian countries. Stock assessment and data on export indicates depletion of natural stocks in Saudi Arabia and Oman. Aquaculture trials of high value species (H. scabra) were successful in Saudi Arabia, Oman and Iran with prospects for further expansion. Research on ecotoxicological properties and bioactive substances conducted in Iran demonstrates an immense research potential. Molecular phylogeny, biology, use in bioremediation, and characterisation of bioactive compounds were identified as potential gaps in research. Expanding aquaculture operations could revive exports and recuperate damaged stocks through sea ranching. Furthermore, regional cooperation, networking, training, and capacity building could help fill the gaps in sea cucumber research, which will aid in its effective conservation and management.  相似文献   
26.
<正>Dear Editor,With the intense crowding in mass gatherings such as Hajj,there is a high risk of acquisition of airborne in-fections with the potential for its transmission in the pilgrims’country of origin(Memish Z A,et al.,2014).The risk of importing serious infections from Hajj has escalated since the emergence of the Middle East respiratory syndrome coronavirus(MERS-CoV)in Saudi Arabia and other neighbouring countries from September2012.Active surveillance of Hajj pilgrims in 2012 and 2013  相似文献   
27.
The electrochemical behavior of redox centers in the active site of amine oxidases from lentil seedlings and Euphorbia characias latex was investigated using a mercury film electrode. Tyrosine-derived 6-hydroxydopa quinone (TPQ) and copper ions in the active site are redox centers of these amine oxidases. The enzymes undergo two reduction processes at negative potentials related to the reduction of the TPQ cofactor to the corresponding hydroquinones and the reduction of copper ions, (Cu(II)-->Cu(I)). Copper depleted enzymes, prepared by reduction with dithionite followed by dialysis against cyanide, undergo only one reduction process. Nyquist diagrams, recorded at potentials corresponding to the reduction of cofactors as dc-offset, represent charge transfer impedance followed by a Warburg-type line at low frequencies, indicating the occurrence of a diffusion controlled process in the rate-limiting step of the reduction process.  相似文献   
28.
The objective of this research work was to produce acceptable quality functional foods, namely, extruded snacks, digestive biscuits and pan bread, on a pilot scale, using vitamin E and β-carotene-rich red palm olein (RPOL) and red palm shortening (RPS). These products were evaluated for their chemical composition and sensory quality along with the antioxidants and vitamin contents during the six months of storage at room temperature (22 ± 1 °C). Extruded snacks and digestive biscuits prepared with RPOL and RPS were found to be good sources of these antioxidant vitamins. The average β-carotene content of the control and test snacks at the end of six months of storage ranged from 26.8 to 56.1 mg/kg fat, and from 430.9 to 468.9 mg/kg fat, respectively. The total vitamin E content in control and test snacks made in Plant No. 1 decreased after six months of storage from 786.1 to 704.4 mg/kg fat, and from 765.1 to 695.4 mg/kg fat, respectively. As expected, the total tocotrienol content was four to five times higher than the total tocopherols in control biscuits. The RPOL containing 600–750 ppm of carotenes (mainly α- and β-carotenes), 710–774 ppm of vitamin E, was found to be suitable for industrial application in producing acceptable quality pan bread, digestive biscuits and snacks. These functional foods contained significant amounts of β-carotene and total vitamin E, indicating the possibility of producing such foods rich in these two of the important antioxidant vitamins coming from a natural source. The research findings strongly indicate that good-quality pan bread, extruded snacks and digestive biscuits can successfully be produced to offer healthier eating choices to the consumers of this region, thereby promoting better health and productivity among the population.  相似文献   
29.
3-Nitropropionic acid (3-NP), an irreversible inhibitor of succinate dehydrogenase enzyme (SDH), induces neurodegeneration similar to that observed in Huntington’s disease (HD). Reduction of prepulse inhibition (PPI) of acoustic startle response, locomotor hypoactivity, bilateral striatal lesions as well as brain oxidative stress are major features of HD. The present study was designed to investigate neuroprotective effect of Ginkgo biloba extract (EGb 761) on 3-NP induced neurobehavioral changes and striatal lesions.Rats administered 3-NP (20 mg/kg, s.c.) for five consecutive days exhibited PPI deficits and locomotor hypoactivity whereas, pretreatment of animals with EGb 761 (100 mg/kg, i.p. for 15 days) ahead of and during the induction of HD by 3-NP (20 mg/kg for 5 days starting at day 8) ameliorated 3-NP-induced neurobehavioral deficits. Administration of 3-NP increased the level of striatal malondialdehyde (MDA). This effect was prevented in animals pre-treated with EGb 761. Changes in the level of apoptotic regulatory gene expressions, following 3-NP treatment, were demonstrated as both an up-regulation and a down-regulation of the expression levels of striatal Bax and Bcl-xl genes, respectively. In addition, an up-regulation of the expression level of striatal glyceraldehyde-3-phosphate dehydrogenase (GAPDH) was also observed. Pre-treatment with EGb 761 caused a down-regulation in striatal GAPDH and Bax together with an up-regulation of striatal Bcl-xl expression level as compared to the 3-NP treated group. Histochemical examination of striatal tissue showed that EGb 761 significantly prevented 3-NP induced inhibition of SDH activity. Histopathological examination further affirmed the neuroprotective effect of EGb 761 against 3-NP toxicity.Taken together, these results suggest that EGb 761 has a neuroprotective role in the current HD paradigm, which may be related to improvement of energy metabolism, antioxidant properties and antiapoptotic effects.  相似文献   
30.
Puerarin (daidzein-8-C-glucoside), a major isoflavone glycoside purified from Pueraria lobata, is well reported to have a neuroprotective effect primarily by the antioxidant mechanisms. This investigation was designed to evaluate the efficacy of Puerarin (Pur) to offset 3-nitropropionic acid (3-NP) induced neurotoxicity. Male Wistar strain rats were given 3-NP (20 mg/kg, s.c.) over five consecutive days, whereas Pur (200 mg/kg, i.p.) was administrated 30 min before 3-NP. Rats treated with 3-NP exhibited significant weight loss, reduction of the prepulse inhibition, locomotor hypoactivity and hypothermia. The striata, hippocampi and cortices of the 3-NP treated rats showed abnormal levels of neurotransmitters, oxidative damage and characteristic histopathological lesions. Treatment with Pur ahead of 3-NP, significantly prevented weight loss, PPI deficit, locomotor hypoactivity and hypothermia. Pur treatment blocked the 3-NP-induced neurotransmitters abnormalities (GABA, DA, 5-HT and NE), and normalized the oxidative stress biomarkers (lipid peroxidation, reduced glutathione, glutathione peroxidase). Histopathological examination further affirmed Pur’s neuroprotective effect against 3-NP-induced neurotoxicity. In conclusion, Pur protected the brain tissues from 3-NP induced neurotoxicity primarily by its neuromodulation and antioxidant effect.  相似文献   
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