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An analytical expression for the drying time of thin lumber is derived, based on a method presented in this study. The laws of moisture content change in wood as function of mass transfer are used for the theoretical approach. The diffusion equation for moisture content is set up for a three-dimensional block of lumber based on the assumption of uniform initial distribution of moisture throughout the specimen. The boundary condition stipulates that the moisture gradient at the boundary is proportional to the deviation of the moisture content of the slab from the equilibrium value at that temperature. These conditions are used to derive an analytical expression for the time required to get from an initial moisture distribution to a desired final moisture content of thin lumber. For a sample calculation, the result of drying time agrees within 10% with the prediction of previously published analytical formulas for the drying curve. 相似文献
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J Sancho-Pelluz M V Alavi A Sahaboglu S Kustermann P Farinelli S Azadi T van Veen F J Romero F Paquet-Durand P Ekstr?m 《Cell death & disease》2010,1(2):e24
Inherited retinal degenerations, collectively termed retinitis pigmentosa (RP), constitute one of the leading causes of blindness in the developed world. RP is at present untreatable and the underlying neurodegenerative mechanisms are unknown, even though the genetic causes are often established. Acetylation and deacetylation of histones, carried out by histone acetyltransferases (HATs) and histone deacetylases (HDACs), respectively, affects cellular division, differentiation, death and survival. We found acetylation of histones and probably other proteins to be dramatically reduced in degenerating photoreceptors in the rd1 human homologous mouse model for RP. Using a custom developed in situ HDAC activity assay, we show that overactivation of HDAC classes I/II temporally precedes photoreceptor degeneration. Moreover, pharmacological inhibition of HDACs I/II activity in rd1 organotypic retinal explants decreased activity of poly-ADP-ribose-polymerase and strongly reduced photoreceptor cell death. These findings highlight the importance of protein acetylation for photoreceptor cell death and survival and propose certain HDAC classes as novel targets for the pharmacological intervention in RP. 相似文献
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A comprehensive study based on gland and seed micromorphology in Euphorbia (Euphorbiaceae) for species distributed in Iranian highlands is presented. A total of 86 species were studied. The gland structure was examined by direct field observations. Taxonomically important characters of glands were observed and measured: size, texture, shape, color, and horns. For species out of Iran herbarium materials were studied. Seed characteristics were examined using scanning electron microscopy (SEM) as well as dissecting light microscopy. Significant features are: seed size, seed shape, presence of caruncle, shape of caruncle, and seed surface ornamentation. A phylogenetic study using Maximum Parsimony (MP) and Bayesian Inference (BI) was performed based on sequences of nuclear DNA internal transcribed spacers (ITS) for selected species representing the main clades known in Euphorbia and with special focus on the species distributed in Iranian highlands. ITS sequences for 20 accessions representing 19 species are provided for the first time, and 48 accessions of 47 species were used from GenBank. The topologies of both analyses were congruent. The results indicate: (1) four main clades with high supports in subgen. Esula which are appropriate to be recognized at sectional rank. (2) E. larica is nested within clade A including few members of subgen. Rhizanthium and is closely related to sect. Balsamis, which is suggested here to be transferred from subgen. Esula into subgen. Rhizanthium. (3) E. osyridea of the monotypic subsect. Osyrideae is closely related to E. buhsei and to the members of sect. Esula. Tracing morphological characters on the phylogenetic tree shows that several morphological characters, such as seed ornamentation applied in previous subgeneric classification of the subgen. Esula, are homoplasious, but the gland structure and capsule surface characters are more reliable for classification purposes. 相似文献
36.
Parastoo Pourali Behrooz Yahyaei Hatef Ajoudanifar Rahele Taheri Hassan Alavi Ashraf Hoseini 《Current microbiology》2014,69(6):785-793
Different wound dressings with antibacterial property have been surveyed and one among them is bacterial cellulose (BC). Since the BC does not have antibacterial property, the biologically produced silver nanoparticles (SNPs) were impregnated into the BC. For the BC production, Hestrin–Schramm broth was used. Formation of the BC was proven by enzymatic hydrolysis. For SNPs production, the bacterial supernatant was treated with AgNO3 and formation of SNPs was monitored through spectrophotometer, TEM and XRD. For impregnation of SNPs into the BC, the cleaned membrane was placed in the bacterial supernatant that contained 1 mmol of AgNO3. The antibacterial assay was done for the BC/SNPs. Enzymatic hydrolysis proved the presence of the BC. Spectrophotometer and XRD results showed the formation of SNPs. TEM analysis revealed the presence of SNPs with sizes around 5–100 nm. SEM micrographs showed the impregnation of SNPs into the BC. Antibacterial test exhibited the antibacterial activity of the BC/SNPs. 相似文献
37.
Mika Bendiksby Yasaman Salmaki Christian Bräuchler Olof Ryding 《Plant Systematics and Evolution》2014,300(5):961-971
We have investigated the phylogenetic position of Stachys tibetica by use of both plastid (rps16 intron, trnL-F region and matK) and nuclear ribosomal (ITS) DNA sequence data and both parsimony and Bayesian phylogenetic methods. All data corroborate that S. tibetica is extraneous in Stachys (tribe Stachydeae) and suggest a phylogenetic affiliation in a different lamioid tribe, Lamieae. The molecular data suggest that the species is most closely related to the genus Stachyopsis, while most of the morphological data suggest an intermediate position between Stachyopsis and Eriophyton. Due to difficulties in distinguishing Stachyopsis and Eriophyton, and the possible embedding of the former in the latter genus, we prefer to amalgamate the two closely related genera and refer S. tibetica to the expanded Eriophyton. As a consequence, five new combinations are made: Eriophyton lamiflorum (Rupr.) Bräuchler, Eriophyton maleolens (Rech.f.) Salmaki, Eriophyton marrubioides (Regel) Ryding, Eriophyton oblongatum (Schrenk) Bendiksby and Eriophyton tibeticum (Vatke) Ryding. 相似文献
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Nadali Alavi Ali-Reza Mesdaghinia Kazem Naddafi Ghasemali Mohebali Hiua Daraei Afshin Maleki 《Soil & Sediment Contamination》2014,23(5):586-597
Microbial degradation of hydrocarbons in soils polluted by oil-based drilling mud and cuttings has been investigated by static methods such as composting or biopiling. Bioremediation of polluted soils by oil-based drilling cuttings through a slurry bioreactor has not previously been reported. The main aim of this work is to monitor hydrocarbon biodegradation in slurry of drilling cuttings and unpolluted soils and the effects of nutrients on it. Indigenous, bacterial-mixed culture isolated from a polluted soil by drilling cuttings adapted to drilling mud concentrations up to 15% (v/v) was done during a 15-month program. The total petroleum hydrocarbons’ (TPHs) removal efficiency in C/N/P 100/5/1 ratio was 90.5 and 79.85% under experimental and control conditions, respectively. The microbial count on the first day, 15 × 107 CFUg?1, reached 20 × 109 CFUg?1on the twenty-first day at experimental conditions. The TPH removal efficiency in C/N/P 100/10/2 was 92.5 and 82.25% at experiment and control, respectively. Increasing nitrogen and phosphorous amount couldn't increase microbial count in comparison with C/N/P ratio 100/5/1. The measured biomass contents and microbial counts in experiments were significantly higher than the control and confirmed hydrocarbons’ biodegradation during the time. Results showed that slurry bioreactors could accelerate the biodegradation of TPHs and reduce remediation time in soil polluted by oil-based drilling cuttings. 相似文献
40.
Amir Ali Rahsepar Asadollah Mirzaee Fatemeh Moodi Mohsen Moohebati Shima Tavallaie Fatemeh Khorashadizadeh Ali Eshraghi Maryam-Sadat Alavi Laya Zarrabi Mostafa Sajjadian Maral Amini Roshanak Khojasteh Roghayeh Paydar Somayeh Mousavi Majid Ghayour-Mobarhan Gordon A. Ferns 《Cell stress & chaperones》2013,18(1):65-74
The relationship between serum anti-heat shock protein (Hsp)27 antibody and high sensitive C-reactive protein (hs-CRP) levels and indices of cardiac function were investigated in patients undergoing coronary artery bypass grafting (CABG) or heart valve replacement. The changes in anti-Hsp27 antibody titers and hs-CRP levels were compared among patients undergoing off-pump and on-pump CABG or valvular heart replacement. Fifty-three patients underwent off-pump, on-pump CABG, and heart valvular replacement in each group. Serum anti-Hsp27 titers and hs-CRP values were measured 24 h before and after the operation and at discharge. Echocardiography was performed before surgery and before discharge. The results were compared with values from 83 healthy controls. hs-CRP levels increased and anti-Hsp27 antibody decreased following surgery (P < 0.001 and P < 0.05, respectively), although these changes were independent of operative procedure (P = 0.361 and P = 0.120, respectively). Anti-Hsp27 antibody levels were higher at the time of discharge (P = 0.016). Only in coronary patients were anti-Hsp27 antibody levels negatively associated with E/E′ (r = −0.268, P = 0.022), a marker of pulmonary capillary wedge pressure. In conclusions, anti-Hsp27 antibody levels are associated with indices of cardiac function in coronary patients. Cardiopulmonary bypass had no significant effect on the induction of changes in anti-Hsp27 levels. Moreover, anti-Hsp27 antibody levels fell in all groups postoperatively; this may be due to the formation of immune complexes of antigen–antibody, and antibody levels were higher at the time of discharge.