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21.
Eight new and four known peptaibols were isolated from a strain of the fungus, Trichoderma atroviride (NF16), which was cultured from an Axinellid sponge collected from the East Mediterranean coast of Israel. The structures of the pure compounds were determined using HRMS, MS/MS and one- and two-dimensional NMR measurements. The isolated compounds belong to the trichorzianines, a family of 19-residue linear hydrophobic peptides containing a high proportion of α-aminoisobutyric acid (Aib), an acetylated N-terminus and a C-terminal amino alcohol. These new peptaibols exhibited antimicrobial activity against environmental bacteria isolated from the Mediterranean coast of Israel. 相似文献
22.
Irina GARCIA-ISPIERTO M. Angels ROSELLó Fabio DE RENSIS Fernando LóPEZ-GATIUS 《The Journal of reproduction and development》2013,59(6):544-548
This study compared the efficiency of a five-day or standard (nine-day)
progesterone-based regimen combined with equine chorionic gonadotrophin (eCG) in a
fixed-time AI (FTAI) protocol for dairy cows. The data examined were derived from
3577 inseminations conducted in three dairy herds. Animals with no estrus signs
detected over 21 days were randomly assigned to a PRID-9 or PRID-5 group. Cows in
each group received a progesterone intravaginal device (PRID) for 9 or 5 days,
respectively, PGF2α and eCG on PRID removal, and GnRH 48 h later.
Fixed-time AI was performed 12 h after the GnRH dose. Cows artificially inseminated
following spontaneous estrus during the study period were considered as controls.
Based on the odds ratio, the likelihoods of animals in PRID-9 in the warm (conception
rate [CR] of 22.3%) and cool (32% CR) periods, and control animals in the warm period
(26.6% CR) becoming pregnant were reduced (by factors of 0.6, 0.3 and 0.4,
respectively) compared with the control animals in the cool period (CR of 43.7%). The
risk of a twin pregnancy was higher (51.4%) for cystic PRID-9 cows (by a factor of
3.6) and lower (9.9%) for cyclic PRID-5 animals (by a factor of 0.4) compared with
the PRID-9 cyclic cows. These findings indicate that the proposed protocol achieves
similar results during the cool or warm season to those obtained when AI is conducted
at spontaneous estrus during the cool season. In addition, PRID-5 reduced twin
pregnancy compared with PRID-9. 相似文献
23.
Irina Vladimirovna KIRILLOVA Fedor Kasperovich SHIDLOVSKIY Andrei Valerievich ZINOVIEV 《Integrative zoology》2019,14(3):270-279
A total of 175 metapodials (MP) of Pleistocene and early Holocene bison (Bison priscus Boj.) from the vast area of northeast Russia were studied. MP were attributed to males and females both visually and statistically. Data on the withers height of bison from northeast Russia are provided. Stress markers were recorded, including so‐called “buttresses.” With rare exceptions, stress markers were not of a pathological nature. The origin and development of the buttresses are age‐related; their prevalence in bison females can be considered as the response to an increased load during pregnancy. Changes in the periosteum, found in males, are related to their greater activity. Buttresses are also well developed on metatarsals of the red deer and the elk; they are less developed in reindeer and not found in giant deer. A relationship among stress markers, locomotion and the environment is established. Possible peculiarities of the Rauchua River bison locomotion are discussed. 相似文献
24.
Natalia A. Kulikova Olga I. Filippova Alexander B. Volikov Irina V. Perminova 《Journal of Soils and Sediments》2018,18(4):1400-1408
Purpose
The purpose of the present study is to evaluate slow-release nitrogen capabilities of soil amendments obtained by modification of humic materials from peat and lignite with alkoxyorganosilanes carrying different amine substituents.Materials and methods
The humates from lignite and peat were modified using (3-aminopropyltriethoxy)-silane (APTES) and (1-aminohexamethylenene, 6-aminomethylene)-triethoxysilane (AHATES). The obtained derivatives were characterized using elemental analysis and Fourier transform infrared spectroscopy. Nitrogen release in the form of ammonia or nitrate was evaluated using dissolution tests under sterile aqueous conditions as well as long-term soil experiments. Ammonium and nitrate were determined using ion-selective electrodes. Activity index (AI) was calculated from the dissolution tests. For soil trials, arable Retisol was sampled from 0- to 5-cm layer in Yaroslavl region (Russia). The soil experiments were conducted over 78 days using (NH4)2SO4 as an activator of nitrification and 3-amino-1,2,4-triazole as an inhibitor of autotrophic nitrifying bacteria.Results and discussion
Modification of lignite and peat humates leads to an increase in nitrogen content up to 2 and 4.3 %, respectively, in case of APTES, and up to 3 and 6 %, respectively, in case of AHATES. All humic derivatives gradually released N upon dissolution in water over 6 days up to 51 % of the total N. The AI values ranged from 4 to 13 %. Amendment of soil with the modified humic materials induced an increase in nitrate content resulting from nitrification of released ammonia by soil microflora. This was confirmed by aminotriasole experiments. The nitrogen release occurred slowly: over the first week of incubation, it did not exceed 36–69 % of the total N content. The higher release rate of ammonium nitrogen was observed for CHS-AHATES versus CHS-APTES derivative, whereas no difference was seen between the two peat derivatives, which showed release rate on the level of CHS-AHATES derivative. Positive effect of all modified humic materials lasted over 78 days.Conclusions
Modification of lignite and peat humates with two aminoorganosilanes carrying one and two nitrogen atoms in the amine substituent brought about twofold to threefold enrichment of the parent humic materials with nitrogen, which was capable of slow release upon incubation in soils. It was released in the form of ammonia and transformed to nitrates by autotrophic nitrifying soil microflora. There was no clear relationship established between structure of amine substituent of organosilane and slow-release properties of the corresponding humic derivatives. The conclusion was met that principal application of aminoorganosilane derivatives of humic substances (HS) is soil structuring, whereas nitrogen-fertilizing capabilities might be considered as beneficial added-value feature of these humic products.25.
Fernando L
PEZ-GATIUS Irina GARCIA-ISPIERTO Ronald H.F. HUNTER 《The Journal of reproduction and development》2021,67(4):251
This study sought to establish whether temperature gradients between the cervix, vagina, and rectum at and 7 days post-artificial insemination (AI) were associated with the incidence of pregnancy in lactating dairy cows (Experiment I; n = 90 ovulating cows) and to evaluate temperature gradient dynamics from the time of insemination to 7 days post-AI under heat stress conditions (Experiment II; n = 16 ovulating and 4 non-ovulating cows). In Experiment I, 39 cows (43.3%) became pregnant. The odds ratio for pregnancy was 2.5 for each one-tenth of a degree drop in cervical temperature with reference to the control rectal temperature at the time of AI (P = 0.01), whereas the same decrease in the cervix–rectum temperature differential 7 days post-AI resulted in an odds ratio of 0.44 (P = 0.02). In Experiment II, 5 of the ovulating cows (31.3%) became pregnant. The mean values of the vagina–rectum, vagina–cervix, and cervix–rectum temperature differentials at AI (day 0), 8 h, 24 h, and 7 days post-AI changed significantly from day 0 to day 7 (within-subject effect; P < 0.02) in ovulating cows but not in non-ovulating cows. Temperature differentials on days 0 and 7 were similar between ovulating cows and cows of Experiment I. Overall, our findings support the notion that a temperature differential between the caudal cervical canal and rectum at AI may be an indicator of the likelihood of pregnancy. Possible prospects of confirming estrus at the herd-level are also suggested. 相似文献
26.
Sushkova Svetlana Minkina Tatiana Deryabkina Irina Mandzhieva Saglara Zamulina Inna Bauer Tatiana Vasilyeva Galina Antonenko Elena Rajput Vishnu K?z?lkaya R?dvan 《Journal of Soils and Sediments》2018,18(6):2361-2367
Journal of Soils and Sediments - The investigation of accumulation, migration, and transformation features of benzo[a]pyrene (BaP) in a soil-plant system by using new ecologically friendly... 相似文献
27.
28.
Irina Kouplevatskaya-Buttoud 《Small-Scale Forestry》2009,8(2):231-247
Changes in small-scale forest governance as a reaction to global changes are viewed from the system dynamics perspective,
focused on two levels of dynamic systems: the policy system with sets of interactions at the national level and the management
system at the local level. These interactions are considered through permanent adaptation and re-shaping of stakeholders’
networks and positions provoking further changes in the systems. Empirical evidence has been obtained from two case studies
related to small-scale rural forestry in distinct contexts—France (the Territorial Forestry Charters) and Kyrgyzstan (collaborative
forest management and leasing of forest plots)—and viewed through a theoretical framework of social-political systems dynamics.
The changes caused by the systems’ capacity for adaptability and resilience are expressed through a double spiral of decision-making,
characterising the interactions between national policies and local management practices. The analysis leads to a conclusion
that changes are basically determined by the formal and informal stakeholders’ strategies developed in a specific context
and their mutual adaptation aimed at system resilience.
相似文献
Irina Kouplevatskaya-ButtoudEmail: |
29.
Irina Shtangeeva 《Communications in Soil Science and Plant Analysis》2017,48(19):2338-2346
Till now information on bromine (Br) in the environment is still incomplete. The purposes of this research were the following: to study accumulation of Br in plants grown under different environmental conditions and to assess the factors controlling Br uptake by different plant species when the plants grow in soil uncontaminated with Br. For the determination of Br and other elements, neutron activation analysis was used. This method allows for determining a wide range of elements in various samples with high sensitivity and accuracy. Model tests and greenhouse experiments demonstrated different abilities of plants to uptake Br from various media and transfer it from roots to upper plant parts. It was shown that the main source of Br for a plant was soil. As a result of the plant growth concentration of Br in the rhizosphere soil decreased. The characteristics of soil have a pronounced effect on the Br uptake by plants. 相似文献
30.
SARAPULTSEV Alexey RANTSEV Maxim SARAPULTSEV Petr MEDVEDEVA Svetlana DANILOVA Irina 《园艺学报》2013,29(10):1870-1876
AIM: To establish a one-stage model of experimental acute necrotizing pancreatitis (ANP) in rats characterized by the simplicity of performance and a high degree of repeatability. METHODS: ANP modeling in rats was performed based on modification of the ligation model as follows: synthetic material ligature using an atraumatic needle was performed to capture pancreatic gland ducts and marginal duodenum vessels. Ligature tips were exteriorized to the abdominal wall, and the ligature was skinned over to avoid catching intestine loops. Pancreatic macroscopic appearance and histological changes were observed. Blood biochemical and hemostatic indicators were also determined. RESULTS: Laboratory analysis of rats with experimental ANP showed a pattern of disturbances similar to that observed during pancreatic necrosis in humans as soon as the first day. General blood analysis revealed enhanced leukocytosis and alterations in leukogram characteristics, indicating acute inflammation. Serum levels of amylase, aspartate aminotransferase and creatinine significantly increased (P<0.05). Hemostatic indicators showed alterations indicating formation of disseminated intravascular coagulation, and signs of endotoxicosis were observed. These typical pancreatic necrosis patterns of disturbances were validated by the results of histological investigation. CONCLUSION: Histological changes and laboratory indicators confirm the development of a suitable model of ANP. 相似文献