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61.
Crows (Corvus splendens) and white herons (Ardea alba) inhabit the agricultural landscapes nearby human habitats which represent dynamic ecosystem and show seasonal crop patterns. We studied the movement pattern in these birds at dawn and dusk, during solstices (December and June) and equinoxes (March and September). The movement directions were changed from uniform at dawn to a concentrated distribution at dusk all along the season suggesting that morning movements are more exploratory than evening with seasonal differences. Differential use of directions in December than June could be the effect of temperature, food availability or wind direction and speed. During breeding, less number of directions used suggests that birds might be moving towards the directions having high probability of food availability. It is likely that avian dispersal in space and time is dependent on the food availability however, further studies are required to be carried out. 相似文献
62.
Suitability of tomato leaves for larval development of Potato Tuber Moth,Phthorimaea operculella (Zeller) (Lepidoptera: Gelechiidae) 总被引:1,自引:0,他引:1
The potato tuber moth (PTM) is an important pest of the potato plant and its tuber. With the expansion of its geographic range, the PTM could be potential threat to the tomato (Solanum lycopersicum L.), a congeneric species of the potato. To assess that risk, we tested larval feeding and development of PTM on leaves of five cultivated tomato varieties namely Moneymaker, Campari, Ailsa Craig, LA3475, E6203 and one wild tomato variety S. pimpinellifolium. PTM larvae accepted all tested plant leaves and developed into adults. Larval development was fastest on the Ailsa Craig variety. Pupae developed fastest on the Moneymaker variety and slowest on LA3475. Host acceptance and survival were highest on Ailsa Craig and lowest on LA3475. The significantly highest male proportion occurred on LA3475 variety. The study showed that PTM could be a potential threat to tomato cultivation which is rapidly increasing in temperate regions owing to climate change. 相似文献
63.
Janhvi Pandey Sukhmal Chand Shweta Chaurasiya Raj Kumari D.D. Patra R.K. Verma 《Soil & Sediment Contamination》2019,28(4):395-410
A field experiment was conducted to observe the effect of TS amendments on soil enzymes and phytoremediation potential of two economically important cultivars of geranium. Different doses of TS were applied in soil to examine threshold limit of HMs where geranium cultivars can be grown successfully in contaminated sites. Treatment variation significantly affected pH, EC, OC, N, P, K and HM content in soil after 50 days of incubation. After harvest, both cultivars were examined to assess the impact of various treatments on their fresh herb, dry matter, essential oil yield and HM accumulation. C/G ratio close to 1 was observed at 50 tha?1 sludge treatment in both cultivars. Urease and β-glucosidase activities in soil were maximum at 50 tha?1 whereas dehydrogenase and phosphatase activities were maximum at 100 tha?1 in both cultivars. β-glucosidase, acid and alkaline phosphatase, urease and dehydrogenase activities were relatively high after 85 days over 45 days in both cultivars. Maximum metal uptake was found in roots of cv. Bourbon followed by leaves. Geranium was observed to be a good candidate for phytoremediation as it mitigates metal toxicity by root absorption and cv. Bourbon is better candidate for the same. 相似文献
64.
Deep Raj 《人类与生态风险评估》2019,25(3):659-671
Mercury (Hg), arsenic (As), cadmium (Cd), and lead (Pb) are the major toxic metals released by coal mining activities in the surrounding environment. These metals get accumulated in the soils. The plants grown on the contaminated soil uptake these toxic metals in their roots and aerial parts. This study monitored the bioaccumulation of Hg and other three toxic metals in coal mine soil. The pot study of Hg accumulation in Brassica juncea showed that the extent of Hg uptake by roots and shoots of the plants grown on was high in the mature plant and Hg content in root was higher than the shoot. In the soil of unreclaimed overburden (OB) dump, the toxic metal content was higher than that of reclaimed OB dump which posed high ecological risk in the soil of unreclaimed OB dump. Bioaccumulation coefficient (BAC) value showed that Hg was not accumulated in the leaves of Dalbergia sissoo L., Gmelina arborea, Peltaphorum inerme L., Cassia seamea L, and Acacia mangium L grown on coal mine soil. 相似文献
65.
K. Diraviya Raj G. Mathews P. Dinesh Kumar 《Marine and Freshwater Behaviour and Physiology》2019,52(2):101-105
Gulf of Mannar (GoM) in the southeast coast of India is known for its coral reefs and reef-associated biodiversity. Corals in GoM were affected to a significant extent by climate change-driven coral bleaching in 2016, and are currently recovering. After the bleaching mortality that corals suffered, the competition for space between corals and sponges is obvious in GoM. Rhabdastrella globostellata is a common marine sponge found overgrowing live coral colonies of the patch reefs in GoM at Pattinamaruthoor in March 2019. Underwater assessment of the reef revealed that 60.06% live coral cover was dominated by Acropora corals (81.91%). Among the acroporans 8.23% of colonies were found overgrown by R. globostellata. During the night dives the tiger cowrie Cypraea tigris was observed to feed on R. globostellata. From this observation the present study infers that C. tigris helps the corals fight these sponges, and concludes that tiger cowries should be protected and promoted to tackle climate change implications. 相似文献
66.
The hepatoprotective and antioxidant effect of Cassia fistula Linn. leaf extract on liver injury induced by diethylnitrosamine (DEN) was investigated. Wistar rats weighing 200+/-10g were administered a single dose of DEN (200mg/kg b.w., i.p.) and left for 30 days. For hepatoprotective studies, ethanolic leaf extract (ELE) of C. fistula Linn. (500mg/kg b.w., p.o.) was administered daily for 30 days. AST, ALT, ALP, LDH, gamma-GT and bilirubin were estimated in serum and liver tissue. Lipid peroxidation (LPO), SOD and CAT were also estimated in liver tissue as markers of oxidative stress. DEN induced hepatotoxicity in all the treated animals were evident by elevated serum ALT, AST, ALP and bilirubin levels and a simultaneous fall in their levels in the liver tissue after 30 days. Induction of oxidative stress in the liver was evidenced by increased LPO and fall in the activities of SOD and CAT. ELE administration for 30 days prevented the DEN induced hepatic injury and oxidative stress. In conclusion, it was observed that ELE of C. fistula Linn. protects the liver against DEN induced hepatic injury in rats. 相似文献
67.
Uracil DNA glycosylases (UDGs) excise uracil from DNA and initiate the base (uracil) excision repair pathway. Ung, a highly conserved protein, is the only UDG characterized so far in mycobacteria. Here, we show that Rv1259 from Mycobacterium tuberculosis codes for a double-stranded DNA (dsDNA) specific UDG (MtuUdgB). MtuUdgB is thermo-tolerant, contains Fe-S cluster and, in addition to uracil, it excises ethenocytosine and hypoxanthine from dsDNA. MtuUdgB is product inhibited by AP-site containing dsDNA but not by uracil. While MtuUdgB excises uracil present as a single-nucleotide bulge in dsDNA, it is insensitive to inhibition by dsDNA containing AP-site in the bulge. Interestingly, in the presence of cellular factors, the uracil excision activity of MtuUdgB is enhanced, and when introduced into E. coli (ung(-)), it rescues its mutator phenotype and prevents C to T mutations in DNA. Novel features of the mechanism of action of MtuUdgB and the physiological significance of the family 5 UDG in mycobacteria have been discussed. 相似文献
68.
69.
Saurabh Kumar Agnihotri Balawant Kumar Ankita Jain Anjali Anjali Mahendra Pal Singh Negi Rekha Sachan Madan Lal Brahma Bhatt Raj Kamal Tripathi Monika Sachdev 《Reports of Biochemistry & Molecular Biology》2022,10(4):711
Background:This study correlates the serum levels of sCD95 & TNF-α with a simple cell-based assay to evaluate the capacity of the serum sample to induce apoptosis in Jurkat cells. Interlinking of these parameters can be explored to design a minimum invasive diagnostic strategy for cervical cancer (CC).Methods:Sera samples were assessed to induce apoptosis in Jurkat cells through FACS. Serum levels of sCD95 and TNF-α were measured by ELISA. JNK phosphorylation was evaluated in sera incubated Jurkat cells. Data was scrutinized through statistical analysis.Results:Significantly higher serum levels of sCD95 and lower TNF-α levels were observed in CC patients; their sera samples inhibited induction of apoptosis in Jurkat cells through reduced JNK phosphorylation. Statistical analysis linked these three parameters for the early screening of CC.Conclusion:Distinct sera levels of sCD95 & TNF-α in CC patients showed an anti-apoptotic effect, which can be considered for early detection of CC.Key Words: Apoptosis, sCD95, Jurkat Cells, Tumor Necrosis Factor-alpha, Uterine Cervical Neoplasms 相似文献
70.
Anna S. Weiss Anna G. Burrichter Abilash Chakravarthy Durai Raj Alexandra von Strempel Chen Meng Karin Kleigrewe Philipp C. Münch Luis Rssler Claudia Huber Wolfgang Eisenreich Lara M. Jochum Stephanie Ging Kirsten Jung Chiara Lincetto Johannes Hübner Georgios Marinos Johannes Zimmermann Christoph Kaleta Alvaro Sanchez Brbel Stecher 《The ISME journal》2022,16(4):1095
A key challenge in microbiome research is to predict the functionality of microbial communities based on community membership and (meta)-genomic data. As central microbiota functions are determined by bacterial community networks, it is important to gain insight into the principles that govern bacteria-bacteria interactions. Here, we focused on the growth and metabolic interactions of the Oligo-Mouse-Microbiota (OMM12) synthetic bacterial community, which is increasingly used as a model system in gut microbiome research. Using a bottom-up approach, we uncovered the directionality of strain-strain interactions in mono- and pairwise co-culture experiments as well as in community batch culture. Metabolic network reconstruction in combination with metabolomics analysis of bacterial culture supernatants provided insights into the metabolic potential and activity of the individual community members. Thereby, we could show that the OMM12 interaction network is shaped by both exploitative and interference competition in vitro in nutrient-rich culture media and demonstrate how community structure can be shifted by changing the nutritional environment. In particular, Enterococcus faecalis KB1 was identified as an important driver of community composition by affecting the abundance of several other consortium members in vitro. As a result, this study gives fundamental insight into key drivers and mechanistic basis of the OMM12 interaction network in vitro, which serves as a knowledge base for future mechanistic in vivo studies.Subject terms: Microbiome, Microbial ecology 相似文献