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1.
We examined the carbon stock and rate of carbon sequestration in a tropical deciduous forest dominated by Dipterocarpus tuberculatus in Manipur,North East India.Estimation of aboveground biomass was determined by harvest method and multiplied with density of tree species.The aboveground biomass was between18.27–21.922 t ha-1and the carbon stock ranged from9.13 to 10.96 t C ha-1across forest stands.Aboveground biomass and carbon stock increased with the increase in tree girth.The rate of carbon sequestration varied from1.4722 to 4.64136 t ha-1year-1among the dominant tree species in forest stands in tropical deciduous forest area.The rate of carbon sequestration depends on species composition,the density of large trees in different girth classes,and anthropogenic disturbances in the present forest ecosystem.Further work is required to identify tree species having the highest potential to sequester CO2 from the atmosphere,which could lead to recommendations for tree plantations in a degraded ecosystem.  相似文献   
2.
Mango and papaya, which are rich sources of beta-carotene, are widely consumed in India. In this study, beta-carotene content and its bioaccessibility were determined in six locally available varieties of mango, namely, Badami, Raspuri, Mallika, Malgoa, Totapuri, and Neelam, and two varieties of papaya, namely, Honey Dew and Surya. Varietal differences were evident in both beta-carotene content and its bioaccessibility in the case of mango. beta-Carotene content in ripe mango ranged from 0.55 +/- 0.03 mg/100 g in the Malgoa variety to 3.21 +/- 0.25 mg/100 g in the Badami variety. Similarly, in the Honey Dew and Surya varieties of papaya, beta-carotene contents were 0.70 +/- 0.10 and 0.74 +/- 0.12 mg/100 g, respectively. Bioaccessibility of beta-carotene ranged from 24.5% in Badami to 39.1% in Raspuri varieties of mango. Considering both the percent bioaccessibility and the inherent beta-carotene content, the amount of bioaccessible beta-carotene was highest in the Mallika variety (0.89 mg/100 g), followed by Badami (0.79 mg/100 g). Because mango and papaya are also consumed as a blend with milk, the influence of the presence of milk on the bioaccessibility of beta-carotene from these fruits was also examined. Addition of milk generally brought about a significant increase in the bioaccessibility of beta-carotene from mango, the increase ranging from 12 to 56%. Bioaccessibility of beta-carotene from the two varieties of papaya examined was similar (31.4-34.3%). Addition of milk increased this bioaccessibility by 19 and 38% in these two varieties. Considering the beta-carotene content of mango and papaya, the latter has to be consumed in amounts roughly 3 times that of mango to derive the same amount of beta-carotene. Thus, this study has indicated that varietal differences exist in the content and bioaccessibility of beta-carotene in mango and that the addition of milk is advantageous in deriving this provitamin A from the fruit pulp of mango and papaya.  相似文献   
3.
Fish Physiology and Biochemistry - Yolk processing pathways vary in the oocytes of benthophil and pelagophil teleosts. The present study investigated the yolk processing pattern in the oocytes of...  相似文献   
4.
Polycyclic aromatic hydrocarbons(PAHs) in soil retain for a quite long period due to their hydrophobicity and aggregation properties. Biofilm-forming marine bacterial consortium(named as NCPR), composed of Stenotrophomonas acidaminiphila NCW702,Alcaligenes faecalis NCW402, Pseudomonas mendocina NR802, Pseudomonas aeruginosa N6P6, and Pseudomonas pseudoalcaligenes NP103, was used for the bioremediation of PAHs in a soil microcosm. Phenanthrene and pyrene were used as reference PAHs. Parameters that can affect PAH degradation, such as chemotaxis, solubility of PAHs in extracellular polymeric substances(EPS), and catechol2,3-dioxygenase(C23O) activity, were evaluated. P. aeruginosa N6P6 and P. pseudoalcaligenes NP103 showed chemotactic movement towards both the reference PAHs. The solubility of both the PAHs was increased with an increase in EPS concentration(extracted from all the 5 selected isolates). Significantly(P 0.001) high phenanthrene(70.29%) and pyrene(55.54%) degradation was observed in the bioaugmented soil microcosm. The C23O enzyme activity was significantly(P 0.05) higher in the bioaugmented soil microcosm with phenanthrene added at 173.26 ± 2.06 nmol min~(-1) mg~(-1) protein than with pyrene added at 61.80 ± 2.20 nmol min~(-1) mg~(-1) protein. The C23O activity and gas chromatography-mass spectrometer analyses indicated catechol pathway of phenanthrene metabolism. However, the metabolites obtained from the soil microcosm added with pyrene revealed both the catechol and phthalate pathways for pyrene degradation.  相似文献   
5.
Progesterone (P4) plays a key role in the establishment and maintenance of pregnancy in most mammals. Unravelling the expression of progesterone‐regulated genes can expand the understanding of the embryonic mortality. Accordingly, we studied the relative mRNA expression of the P4‐regulated genes in the buffalo. Uteri were collected from the abattoir and categorized into nonpregnant late luteal phase, stage I (28–38th days of gestation) and stage II (48–56th days of gestation) of pregnancy (n = 6/group). After extraction of total RNA from the endometrial tissues, we carried out qRT‐PCR for determining the relative mRNA expression of the P4‐regulated genes using nonpregnant late luteal phase as calibrator group. The expression of LGALS3BP (essential for maternal recognition of pregnancy) gene was found to be significantly upregulated (p < 0.05), while MUC1 (important for embryo attachment) gene was downregulated in stage I and II of pregnancy. We observed no significant change in the expression of LGALS1, LGALS9 and CTSL genes. The SLC5A11 and SLC2A1 genes (involved in the transport of glucose to endometrium) in early pregnancy were upregulated in the pregnancy stage I (p < 0.05) relative to nonpregnant late luteal phase. The CST3 gene was significantly upregulated in pregnancy stage II (p < 0.01). These results provide molecular insights into the specific pathways involved in foeto‐maternal communication during early pregnancy in buffaloes.  相似文献   
6.
The innate immune system, particularly the external body surface, plays a frontier role in protecting fish from relevant infections. The present study is aimed at understanding and comparing the mucosal immunity of Indian major carp, that is, Labeo rohita, Catla catla and Cirrhinus mrigala, by evaluating different immune parameters such as protein content, lysozyme, myeloperoxidase, proteases and alkaline phosphatase activity in the skin mucus. The protein content of mucus sample of these species was compared, and the highest protein content was found in C. catla among the three Indian major carp species. The levels of proteases (40 ± 0.211 units/ml) and myeloperoxidase OD450 nm (1.525 ± 0.108) were found to be highest in the skin mucus of C. catla. However, lysozyme levels were highest in the skin mucus of L. rohita (10.95 ± 0.330 μg/ml), and C. mrigala had the highest alkaline phosphatase activity (30.74111 ± 0.680 U/l). Besides the enzyme activities, the epidermal mucus samples of three Indian major carp species were also tested and compared for the antibacterial activity against seven bacterial strains. Skin mucus of C. catla showed highest antibacterial activity among the three Indian major carps against all the seven bacterial strain, except that Micrococcus lysodeikticus and Vibrio cholerae, however, showed highest activity against mucus of C. mrigala. Also, the epidermal mucus from all the three species successfully agglutinated three freshwater pathogens, viz. Aeromonas hydrophila, Pseudomonas fluorescens and Edwardsiella tarda, with agglutination titres being the highest for Labeo rohita for all the pathogens. The epidermal mucus samples from the Indian major carp species showed haemagglutination activity and successfully lysed human, chicken and goat RBCs showing highest activity in C. catla. These results provide information for a better understanding of the role of epidermal mucus and its components in the innate immune system of Indian major carps.  相似文献   
7.
Forty varieties of sorghum grown locally and four cereals were screened for inhibitory activity against human salivary amylase. Three varieties of sorghum (IS-22422, Nagi Monadi and Ngd Marnm) had maximum inhibitory activity of 124 units. Among the cereals rice had the lowest inhibitory activity. Amylase inhibitory activity was lost on germination and heating the seeds.  相似文献   
8.
Origin recognition complex (ORC) proteins serve as a landing pad for the assembly of a multiprotein prereplicative complex, which is required to initiate DNA replication. During mitosis, the smallest subunit of human ORC, Orc6, localizes to kinetochores and to a reticular-like structure around the cell periphery. As chromosomes segregate during anaphase, the reticular structures align along the plane of cell division and some Orc6 localizes to the midbody before cells separate. Silencing of Orc6 expression by small interfering RNA (siRNA) resulted in cells with multipolar spindles, aberrant mitosis, formation of multinucleated cells, and decreased DNA replication. Prolonged periods of Orc6 depletion caused a decrease in cell proliferation and increased cell death. These results implicate Orc6 as an essential gene that coordinates chromosome replication and segregation with cytokinesis.  相似文献   
9.
In the present study, thiourea-induced thyroid hormone depletion and thyroxine (T4) ‘overdose’ were used as a strategy to understand the influence of thyroid hormones on ovarian recrudescence of juvenile (3-months-old), immature (8-months-old) and adult (1-year-old) air-breathing catfish, Clarias gariepinus. Thiourea-induced thyroid hormone depletion in juvenile catfish impaired ovarian development, but no significant effect was observed in immature catfish and during late stage of ovarian recrudescence of mature catfish. T4 treatment in females undergoing late stages of ovarian recrudescence induced rapid oocyte growth by promoting its early entry into maturational phase as evident from the presence of more number of vitellogenic and post-vitellogenic follicles, decrease in aromatse immunoreactivity and reduced estradiol–17β levels. Hence, thyroid hormones have an important role to play during early stages of ovarian development and vitellogenesis of catfish and also indicating that thyroid has a stage dependent effect on ovary.  相似文献   
10.
Infectious and inflammatory diseases have repeatedly shown strong genetic associations within the major histocompatibility complex (MHC); however, the basis for these associations remains elusive. To define host genetic effects on the outcome of a chronic viral infection, we performed genome-wide association analysis in a multiethnic cohort of HIV-1 controllers and progressors, and we analyzed the effects of individual amino acids within the classical human leukocyte antigen (HLA) proteins. We identified >300 genome-wide significant single-nucleotide polymorphisms (SNPs) within the MHC and none elsewhere. Specific amino acids in the HLA-B peptide binding groove, as well as an independent HLA-C effect, explain the SNP associations and reconcile both protective and risk HLA alleles. These results implicate the nature of the HLA-viral peptide interaction as the major factor modulating durable control of HIV infection.  相似文献   
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