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181.
Coral spawning on the oceanic reef systems of north-western Australia was recently discovered during autumn and spring, but the degree to which species and particularly colonies participated in one or both of these spawnings was unknown. At the largest of the oceanic reef systems, the participation by colonies in the two discrete spawning events was investigated over three years in 13 species of Acropora corals (n = 1,855 colonies). Seven species spawned during both seasons; five only in autumn and one only in spring. The majority of tagged colonies (n = 218) spawned once a year in the same season, but five colonies from three species spawned during spring and autumn during a single year. Reproductive seasonality was not influenced by spatial variation in habitat conditions, or by Symbiodinium partners in the biannual spawner Acropora tenuis. Colonies of A. tenuis spawning during different seasons separated into two distinct yet cryptic groups, in a bayesian clustering analysis based on multiple microsatellite markers. These groups were associated with a major genetic divergence (G”ST = 0.469), despite evidence of mixed ancestry in a small proportion of individuals. Our results confirm that temporal reproductive isolation is a common feature of Acropora populations at Scott Reef and indicate that spawning season is a genetically determined trait in at least A. tenuis. This reproductive isolation may be punctuated occasionally by interbreeding between genetic groups following favourable environmental conditions, when autumn spawners undergo a second annual gametogenic cycle and spawn during spring.  相似文献   
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This study investigated the effects of clothing providing different Clo values upon the circadian rhythm of sympathetic nervous activity, as inferred from urinary catecholamine excretion and heart rate, in a thermoneutral environment. Seven health female subjects were studied for 37.5 h, from 21:00 h on the first day to 10:30 h on the third day, in an isolated climatic chamber controlled at 23.8?±?0.2 °C and 60?±?5% RH. Light intensity was 500 lux from 06:30 to 19:30 h, 100 lux from 19:30 to 22:30 h and 0 lux from 22:30 to 06:30 h. Subjects were tested while wearing two different types of clothing: Type L, offering 1.048 Clo of thermal insulation and with the subjects’ extremities covered; and Type H, 0.744 Clo of thermal insulation and the subjects’ extremities exposed. Urine samples were collected every 4 h, their volumes were measured and they were later assayed for their contents of adrenaline and noradrenaline; the mean heart rate for each of these 4-h periods was also calculated. The daily profiles of the variables were assessed by ANOVA, which indicated that the amplitudes and phases of the daily rhythms differed between the clothing types. This result was examined in more detail by assessing the profiles by single and group cosinor analysis (period = 24 h). All four physiological variables showed clear and statistically significant group cosinor rhythms with both types of clothing. The mean amplitudes of urine flow, the excretion rate of urinary adrenaline and heart rate were greater when wearing Type H rather than Type L clothing (p = 0.01 for urine flow and heart rate; p = 0.072 for rate of excretion of adrenaline). Also, the acrophase of the rate of urinary adrenaline excretion was earlier in all subjects wearing Type H rather than Type L clothing (p = 0.048), and the acrophases of urine flow and urinary noradrenaline excretion rate were earlier in six and five of the subjects, respectively. These results show that clothing which is worn in an environment of moderate temperature (23.8 °C) and which offers a lower Clo value (especially if the distal extremities are exposed) might induce an increase in amplitude and/or an advance of acrophase in circadian rhythms of urine flow, excretion of urinary catecholamines and heart rate. It is suggested that these rhythmic changes, which imply changes in the daily profile of sympathetic nervous system activity, might be important when daily thermoregulation and comfort in response to the type of clothing being worn in daily life are considered.  相似文献   
184.
AimTo analyse the efficacy and toxicity of postprostatectomy SRT in patients with a BCR evaluated with mpMRI.BackgroundMultiparametric magnetic resonance imaging (mpMRI) has the ability to detect the site of pelvic recurrence in patients with biochemical recurrence (BCR) after radical prostatectomy (RP). However, we do not know the oncological outcomes of mpMRI-guided savage radiotherapy (SRT).ResultsLocal, lymph node, and pelvic bone recurrence was observed in 13, 4 and 2 patients, respectively. PSA levels were significantly lower in patients with negative mpMRI (0.4 ng/mL [0.4]) vs. positive mpMRI (2.2 ng/mL [4.1], p = 0.003). Median planning target volume doses in patients with visible vs. non-visible recurrences were 76 Gy vs. 70 Gy. Overall, mean follow-up was 41 months (6–81). Biochemical relapse-free survival (bRFS) at 3 years was 82.3% and 82.5%, respectively, for the negative and positive mpMRI groups (p = 0.800). Three-year rates of late grade ≥2 urinary and rectal toxicity were 14.8% and 1.9%, respectively; all but one patient recovered without sequelae.ConclusionSRT to the macroscopic recurrence identified by mpMRI is a feasible and well-tolerated option. In this study, there were no differences in bRFS between MRI-positive and MRI-negative patients, indicating effective targeting of MRI-positive lesions.  相似文献   
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Major knowledge gaps exist regarding effects of landscape-level agroecosystem composition on the presence of natural enemies of agricultural pests. The objective of this study was to evaluate the influence of landscape mosaic characteristics on the diversity of predators and parasitoids of a viticultural landscape in La Rioja, Spain. Five habitats were evaluated: Mediterranean forest, Mediterranean scrub, olive groves, natural grassland, and vineyards. In all, we collected 28,640 arthropods, representing 10 orders: Araneae, Coleoptera, Dermaptera, Diptera, Hemiptera, Hymenoptera, Mantodea, Neuroptera, Solifugae, and Thysanoptera. The grassland habitat presented the highest arthropod abundances. Carabid beetles showed preferences for Mediterranean forest and scrub, whereas reduviid bugs showed preferences for natural grassland. Landscape heterogeneity and connectivity with natural elements in the study area turn out to be effective in conservation of diversity of natural enemies of viticulture.  相似文献   
187.
Ecosystems - When a water reservoir is created, the pre-existing soils and vegetation are flooded. Here, we took advantage of the complete emptying of the Sarrans Reservoir, which was flooded...  相似文献   
188.
The possibility of using the volatile-producing fungus Muscodor albus for biofumigation against building molds was investigated. Several species of Aspergillus and Penicillium as well as fungi belonging to nine other genera were inhibited or killed in vitro by volatiles produced by potato dextrose agar or rye grain cultures of M. albus. Trichoderma viride was the only fungus that was not inhibited by M. albus volatiles. To test biofumigation as a preventative treatment against fungal colonization of building material, dry pieces of gypsum drywall were fumigated with grain cultures of M. albus in closed boxes. After a simulated water damage and incubation under saturated humidity for 2 weeks, untreated drywall developed natural fungal populations of about 10(5)-10(6) cfu/cm2, while drywall fumigated with M. albus culture (20 g/11 L) had nondetectable fungal populations. To test for curative ability, moist pieces of drywall heavily colonized with Cladosporium cladosporioides, Aspergillus niger, or Stachybotrys chartarum were fumigated for 48 h with grain cultures of M. albus. Cladosporium cladosporioides was eliminated within 48 h, while A. niger and S. chartarum were usually more resistant. However, a longer curative fumigation of 96 h was effective in reducing A. niger or naturally occurring mold populations by about 5 log values. The production of volatile organic compounds from 20 g of rye grain culture in 11 L containers was monitored by solid-phase micro extraction and gas chromatography. Concentrations of isobutyric acid, the most abundant volatile, increased gradually in the headspace until it reached 25 microg/L (m/v) within 96 h. The second and third most abundant compounds, 2-methyl-1-butanol and isobutanol, peaked at about 10 and 5 microg/L (m/v), respectively, within the first 24 h and declined gradually afterwards.  相似文献   
189.
The white-rot fungus Trametes versicolor decolorized the mono-azo-substituted naphthalenic dye Amaranth. The relationship between the amount of enzymes present in the system and the efficiency of the decoloration process was investigated. The two responses used to quantify the process of decoloration (i.e., initial decoloration rate, v0, and the percent concentration of dye decolorized in 1 h, %c) were correlated with the amount of three enzymes considered for the study (lignin peroxidase, manganese peroxidase, and laccase) and analyzed through stepwise regression analysis (forward, backward, and mixed). The results of the correlation analysis and those of the regression analysis indicated that lignin peroxidase is the enzyme having the greatest influence on the two responses.  相似文献   
190.
The synthesis of (4,5,6-13C)-deoxymannojirimycin is described. The route employed is based on Sharpless asymmetric epoxidation of (1,2,3-13C)(E)-2,4-pentadien-1-ol and uses ring-closing metathesis as a key step. The labeled compound may be easily used for protein-binding experiments using NMR spectroscopic methods.  相似文献   
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