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171.
Elmira Tavasoli Morteza Sadeghi Hossein Riazi Ahmad Arabi Shamsabadi Masoud Soroush 《Fibers and Polymers》2018,19(10):2049-2055
This paper presents new mixed-matrix membranes (MMMs) synthesized via incorporating hexamethylenetetramine dicyanamide cadmium nanoparticles, a metal organic framework (MOF), into the polysulfone (PSF) matrix. The MMMs are characterized using FTIR and SEM analyses, and their gas permeation properties are evaluated at different MOF loadings and various pressures. The results show that the nanoparticle is compatible with the polymer and distributes homogenously in the matrix. Compared to the pristine PSF membrane, the MMM with 2.5 wt. % of the MOF nanoparticles has lower CO2, CH4, N2 and O2 permeabilities but significantly higher CO2/CH4, CO2/N2 and O2/N2 gas pair selectivities (i.e., 41.66, 20.08 and 5.09, respectively, which are 42.6, 61.6 and 60.02 % higher). As the total pressure increases, the gas permeabilities of the pristine PSF membrane and the MMMs decrease, but their sieving abilities increase. These results suggest that gas selectivities of high free-volume polymers with poor sieving abilities can be improved by incorporating the MOF into the polymer. 相似文献
172.
Seyed Mohammad Moein Sadeghi John Toland Van Stan Thomas Grant Pypker Jelveh Tamjidi Jan Friesen Moein Farahnaklangroudi 《European Journal of Forest Research》2018,137(1):121-130
The temporal dynamics of forest canopy rainfall partitioning are important to forest ecology and management as it influences all subsequent hydrological processes along the rainfall-to-discharge flow path. Despite a growing body of literature on the importance of coupled hydrological–ecological interactions during periodic forest life cycle events, little work has examined how canopy rainfall partitioning varies across transitional leaf states (between the leafed vs. leafless states). This study analyzed a 3 year field monitoring campaign for two tree species in semiarid Iran (Robinia pseudoacacia and Platanus orientalis) to describe rainfall partitioning dynamics across the full-leaf, senescence, leafless, and leafing states. Crown saturation point, canopy storage capacity, free throughfall coefficient and the ratio of wet canopy evaporation rate to mean rainfall intensity were related to decreases/increases in plant area index and canopy closure. The high variability of rainfall partitioning observed in this study highlights the importance of transitional leaf states in the temporal characterization of water inputs to forest surfaces and boundary layer. 相似文献
173.
Zohreh Bahraini Somayyeh Salari Mohsen Sari Jamal Fayazi Mehdi Behgar 《Animal Science Journal》2017,88(9):1425-1435
This study was conducted to compare the effects of electron beam (EB) and gamma ray (GR) irradiation treatments at doses of 10, 20 and 30 kGy on chemical composition, protein quality and protein digestibility of cottonseed meal (CSM). GR irradiation in all doses significantly decreased the crude fiber of samples compared to raw CSM. Free and total gossypol content of CSM was decreased significantly by utilizing both types of irradiation in a dose‐dependent manner. Also, EB irradiation caused decrease in free and total gossypol content more than that of GR irradiation. GR irradiation at doses of 20 and 30 kGy, and EB irradiation at doses of 10, 20 and 30 kGy can significantly decrease protein solubility of CSM compared to that of a raw sample. GR irradiation at a dose of 30 kGy significantly increased apparent digestibility of protein compared to raw and EB irradiation of CSM at a dose of 10 kGy in Leghorn cockerels. Maximum increase in protein digestibility of CSM was observed in GR irradiation at a dose of 30 kGy. In conclusion, the present study showed that EB and GR irradiation reduced gossypol and crude fiber and increased protein digestibility of CSM but had no effect on protein quality of CSM. 相似文献
174.
Rutin promoted resistance of tomato against <Emphasis Type="Italic">Xanthomonas perforans</Emphasis>
Ali Safaie Farahani S. Mohsen Taghavi 《European journal of plant pathology / European Foundation for Plant Pathology》2018,151(2):527-531
Xanthomonas perforans is the causal agent of bacterial spot, one of the most devastating diseases of tomato that results in considerable yield losses worldwide. Rutin, as a polyphenolic substance, was used to induce resistance in tomato against X. perforans. Rutin at concentration of 2 mM had ability to reduce the disease severity of bacterial spot. On the other hand, 2 mM rutin had no antibacterial activity in vitro. Expression profiling of pathogenesis-related gene 5 (PR-5), Phenylalanine ammonia-lyase (PAL) and lipoxygenase (LOX) was probed during the enhanced resistance by rutin. Pretreatment with rutin (rutin/ X. perforans) led to induction of PR-5, PAL and LOX compared to controls (water/ X. perforans). Our results suggest that rutin-induced resistance against X. perforans in tomato might be mediated through stimulation of some defense genes such as PR-5, PAL and LOX. 相似文献
175.
Intraspecific variability in morphological and ecophysiological leaf traits might be theorized to be present in declining populations,since they seem to be exposed to stress and plasticity could be advantageous.Here we focused on declining Persian oaks(Quercus brantii Lindl.var.persica(Jaub and Spach)Zohary)in the Zagros Mountains of western Iran,representing the most important tree species of this region.We selected trees with contrasting crown dieback,from healthy to severely defoliated,to investigate the relationships between canopy dieback and leaf morphology,water content and pigments.We also measured esterase and peroxidase,as enzymatic antioxidants and indicators of contrasting genotypes.Trees showing moderate to severe defoliation showed higher leaf mass area(LMA),reduced relative water content(RWC),and lower stomatal density(SD).Increasing LMA indicates a more sclerophyllic structure,according to drier conditions.We did not find significant differences in leaf pigments(chlorophyll a and b,and carotenoids)among crown dieback classes,suggesting that Persian oak trees are able to maintain accurate photochemical efficiency,while reduced RWC and SD suggest hydraulic limitations.Our results do not provide a consistent pattern as regards enzymatic antioxidant defense in Persian oak.Morphological leaf traits would be important drivers of future adaptive evolution in Persian oak,leading to smaller and thicker leaves,which have fitness benefits in dry environments.Nonetheless,drought responses may be critically affecting carbon uptake,as photosynthetic compounds are less effectively used in leaves with higher sclerophylly. 相似文献
176.
Take home message Mucilage secreted by roots and EPS produced by microorganisms alter the physical properties of the soil solution and impact the water dynamics in the rhizosphere. The high viscosity of mucilage and EPS is responsible for the formation of thin filaments and interconnected thin lamellae that span throughout the soil matrix maintaining the continuity of the liquid phase across the pore space even during severe drying. The impact of these mechanisms on plant and microorganisms needs to be explored. 相似文献
177.
Mehdi Marjani Vahid Akbarinejad Mohsen Bagheri 《Veterinary anaesthesia and analgesia》2015,42(2):178-181
ObjectiveThe aim of the present study was to compare intranasal (INS) and intramuscular (IM) routes of administration of a ketamine-midazolam combination in cats.Study designRandomized block design.AnimalsTwelve healthy mixed breed cats (six males and six females).MethodsThe drug combination was ketamine (14 mg kg−1) and midazolam (0.5 mg kg−1). In the IM group, drugs were injected into quadratus femoris muscle; in the INS. group, the combination dropped equally into the two nostrils. Pulse and respiratory rates, peripheral haemoglobin oxygen saturation (SpO2) and rectal temperature were monitored before and at intervals after drug administration. Time to onset and duration of sedation and, during recovery to head up, sternal recumbency and recovery were recorded.ResultsThere were no significant differences between the groups in any time measured except for recovery to sternal recumbency, where time was lower in the INS than in the IM (p = 0.034). Respiratory rate was greater in the INS than in the IM group (p = 0.029), but there was no difference between groups in other physiological parameters. In both groups SpO2 was low before and fell further during sedation.ConclusionsThe results substantiated that INS ketamine-midazolam can produce effective sedation in cats.Clinical relevanceIntranasal (INS) administration of ketamine-midazolam is atraumatic, and its use may avoid the pain of injection of ketamine combinations when this drug is used to induce sedation in cats. 相似文献
178.
Chemical industry project management involves complex decision making situations that require discerning abilities and methods to make sound decisions. Chemical engineers as project managers are faced with decision environments and problems in chemical industry projects that are complex. Multiple-criteria decision making (MCDM) approaches are major parts of decision theory and analysis. This paper presents all of MCDM approaches for use in chemical engineering management decisions. In this work, case study is Research and Development (R&D) project selection in chemical industry. The ability to make sound decisions is very important to success of R&D projects. It is hoped that this work will provide a ready reference on MCDM and this will encourage the application of the MCDM in chemical engineering management. 相似文献
179.
Comparative study on immunomodulatory and growth enhancing effects of three prebiotics (galactooligosaccharide,fructooligosaccharide and inulin) in common carp (Cyprinus carpio) 下载免费PDF全文
Seyed Hossein Hoseinifar Alireza Ahmadi Mojtaba Raeisi Seyyed Morteza Hoseini Mohsen Khalili Nasser Behnampour 《Aquaculture Research》2017,48(7):3298-3307
This study investigated the effects of different prebiotics, including galactooligosaccharide (GOS), fructooligosaccharide (FOS) and inulin (INL), on skin mucosal immune parameters, humoral immune responses as well as performance of common carp (Cyprinus carpio). Two hundred and forty specimens (13.85 ± 0.85 g) were stocked in 12 fibreglass tanks assigned into three treatments and a control group. The experimental diets were formulated to have equal level (2%) of the prebiotics. At the end of the feeding trial, the highest skin mucus lysozyme activities and total immunoglobulin (total Ig) were observed in GOS‐fed group (P < 0.05). However, skin mucus protease activity showed no significant difference among different dietary groups (P < 0.05). Blood respiratory burst activity was significantly increased in all prebiotic‐fed fish compared to the control group (P < 0.05); the highest activity was observed in GOS treatment. Furthermore, evaluation of humoral immune response revealed that feeding with GOS‐supplemented diet significantly increased lysozyme and alternative complement (ACH50) activity as well as total Ig compared to the control and other prebiotic groups. While no significant difference was observed between FOS and INL groups, common carps fed GOS‐supplemented displayed improved (P < 0.05) growth performance, including final weight, weight gain, specific growth rate (SGR) and feed conversion ratio (FCR), compared to the control treatment. These results revealed that different prebiotics modulate carp growth and immune response in different manner, and GOS seems to be the most suitable prebiotic. 相似文献
180.
The study of antioxidant enzymes and immune‐related genes expression in common carp (Cyprinus carpio) fingerlings fed different prebiotics 下载免费PDF全文
Seyed Hossein Hoseinifar Alireza Ahmadi Mohsen Khalili Mojtaba Raeisi Hien Van Doan Christopher Marlowe Caipang 《Aquaculture Research》2017,48(11):5447-5454
The aim of the present study was to study the effects of different prebiotics (galacto‐, fructooligosaccharide and inulin) on immune response and oxidative stress of common carp (Cyprinus carpio) fingerlings at the molecular level. A total number of 240 fish (13.85 ± 0.85 g) were supplied and randomly stocked in twelve fiberglass tanks (20 specimens per tank). Fish were fed a basal formulated diet (Control) or basal diet supplemented with equal level (2%) of different prebiotics (four treatments repeated in triplicated) for 8 weeks. At the end of feeding trial, the expression of immune‐related genes (interleukin 1 beta [IL‐1β], IL‐8, IL‐10, lysozyme [LYZ], tumour necrosis factor alpha [TNF‐α] and transforming growth factor beta [TGF‐β]) were determined in head kidney and intestine tissues and the expression of antioxidant‐related genes (glutathione S‐transferase [GST‐α], glutathione reductase [GR] and glutathione peroxidase genes [GPX]) were studied in intestine. The results revealed that dietary administration of prebiotics modulated the expression of immune‐related genes and the degree of expression was affected by the type of prebiotics and the organ that was used for analyses. Also, evaluation of antioxidant genes expression showed that GSTα and GR expression levels increased as a result of feeding common carp with the prebiotics. According to these findings, it can be concluded that feeding on different prebiotics had altered effects on the expression of immune and antioxidant‐related genes. 相似文献