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1.
Steven M. Melemis 《The Yale journal of biology and medicine》2015,88(3):325-332
There are four main ideas in relapse prevention. First, relapse is a gradual process with distinct stages. The goal of treatment is to help individuals recognize the early stages, in which the chances of success are greatest. Second, recovery is a process of personal growth with developmental milestones. Each stage of recovery has its own risks of relapse. Third, the main tools of relapse prevention are cognitive therapy and mind-body relaxation, which are used to develop healthy coping skills. Fourth, most relapses can be explained in terms of a few basic rules. Educating clients in these rules can help them focus on what is important: 1) change your life (recovery involves creating a new life where it is easier to not use); 2) be completely honest; 3) ask for help; 4) practice self-care; and 5) don’t bend the rules. 相似文献
2.
L. R. Smales 《International journal for parasitology》1977,7(6):449-456
Smales L. R. The life history of Labiostrongylus eugenii, a nematode parasite of the Kangaroo Island Wallaby (Macropus eugenii): development and hatching of the egg and the free living stages. International Journal for Parasitology7: 449–456. Labiostrongylus eugenii (Trichonematidae) occurs in the stomach of the Kangaroo Island Wallaby. Egg morphology is similar to that of other strongyloids. When incubated at 25°C embryogenesis is completed in about 30 h. An incomplete moult occurs within the egg, and larvae hatch at a sheathed second-stage h later. Development occurred at all temperatures between 2° and 37°C with an optimum about 25°C and an upper limit near 37°C. The hatching process is very rapid, taking about 2 min. It is signalled by increased larval activity followed by a change in shell permeability. The larva hatches at that pole of the shell which has become plastic.The sheathed second-stage larva measures 659.50 ± 22.54 μm by 27.98 ± 1.22 μm. Its internal structures are concealed by a mass of opaque granules which were demonstrated as neutral lipid by oil red O staining. A second incomplete moult at 3–4 days results in a doubly sheathed infective larva from which the lipid gradually disappears. The mouth never appears patent and the larvae neither feed nor grow but rather decrease in size with age. Optimal temperatures for larvae range between 15°–25°C with 37°C about the upper limit. The significance of this developmental pattern is discussed. 相似文献
3.
Alan C. Love 《Philosophical transactions of the Royal Society of London. Series B, Biological sciences》2010,365(1540):679-690
Idealization is a reasoning strategy that biologists use to describe, model and explain that purposefully departs from features known to be present in nature. Similar to other strategies of scientific reasoning, idealization combines distinctive strengths alongside of latent weaknesses. The study of ontogeny in model organisms is usually executed by establishing a set of normal stages for embryonic development, which enables researchers in different laboratory contexts to have standardized comparisons of experimental results. Normal stages are a form of idealization because they intentionally ignore known variation in development, including variation associated with phenotypic plasticity (e.g. via strict control of environmental variables). This is a tension between the phenomenon of plasticity and the practice of staging that has consequences for evolutionary developmental investigation because variation is conceptually removed as a part of rendering model organisms experimentally tractable. Two compensatory tactics for mitigating these consequences are discussed: employing a diversity of model organisms and adopting alternative periodizations. 相似文献
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The brood cycle in anostracans results from the overlapping of two successive reproductive cycles in the genital tract of females. While a clutch of oocytes begins to mature at the ovaries (ovarian period), the nauplii, cysts or unfertilised products of a previous clutch are developing in the ovisac or being released to the medium (oviduct-ovisac period). Models are proposed for the sequence of stages and their duration in a complete brood cycle under two treatments, i.e., females with males (1:1 ratio), and isolated virginal females of Artemia persimilis in laboratory conditions. The whole brood cycle in both treatments took 6 days, however, they differed in the duration of some stages. The differences are discussed and observations on amplexus are added. 相似文献
7.
The nymphs of Antillotolania Ramos and Deiroderes Ramos are described for the first time, along with the first host record for the genus Antillotolania, represented by Antillotolania myricae, sp. n. Nymphal features of both genera, such as a ventrally fused, cylindrical tergum IX (anal tube), the presence of abdominal lamellae, and heads with foliaceous ventrolateral lobes confirm their placement in Membracidae and are consistent with phylogenetic analyses placing them in Stegaspidinae but in conflict with a cladistic analysis showing a closer relationship to Nicomiinae. Head processes and emarginate forewing pads in the last instars of both genera support an earlier estimate, based on nuclear genes, that the two genera form a monophyletic group in Stegaspidinae. Distinguishing features of the four species of Antillotolania are tabulated. 相似文献
8.
Guangzhou Wang Peggy Schultz Alice Tipton Junling Zhang Fusuo Zhang James D. Bever 《Ecology letters》2019,22(8):1221-1232
Which processes drive the productivity benefits of biodiversity remain a critical, but unanswered question in ecology. We tested whether the soil microbiome mediates the diversity‐productivity relationships among late successional plant species. We found that productivity increased with plant richness in diverse soil communities, but not with low‐diversity mixtures of arbuscular mycorrhizal fungi or in pasteurised soils. Diversity‐interaction modelling revealed that pairwise interactions among species best explained the positive diversity‐productivity relationships, and that transgressive overyielding resulting from positive complementarity was only observed with the late successional soil microbiome, which was both the most diverse and exhibited the strongest community differentiation among plant species. We found evidence that both dilution/suppression from host‐specific pathogens and microbiome‐mediated resource partitioning contributed to positive diversity‐productivity relationships and overyielding. Our results suggest that re‐establishment of a diverse, late successional soil microbiome may be critical to the restoration of the functional benefits of plant diversity following anthropogenic disturbance. 相似文献
9.
Lei Chen Jian‐Guo Huang Qianqian Ma Heikki Hnninen Francine Tremblay Yves Bergeron 《Global Change Biology》2019,25(3):997-1004
Contrary to the generally advanced spring leaf unfolding under global warming, the effects of the climate warming on autumn leaf senescence are highly variable with advanced, delayed, and unchanged patterns being all reported. Using one million records of leaf phenology from four dominant temperate species in Europe, we investigated the temperature sensitivities of spring leaf unfolding and autumn leaf senescence (ST, advanced or delayed days per degree Celsius). The ST of spring phenology in all of the four examined species showed an increase and decrease during 1951–1980 and 1981–2013, respectively. The decrease in the ST during 1981–2013 appears to be caused by reduced accumulation of chilling units. As with spring phenology, the ST of leaf senescence of early successional and exotic species started to decline since 1980. In contrast, for late successional species, the ST of autumn senescence showed an increase for the entire study period from 1951 to 2013. Moreover, the impacts of rising temperature associated with global warming on spring leaf unfolding were stronger than those on autumn leaf senescence. The timing of leaf senescence was positively correlated with the timing of leaf unfolding during 1951–1980. However, as climate warming continued, the differences in the responses between spring and autumn phenology gradually increased, so that the correlation was no more significant during 1981–2013. Our results further suggest that since 2000, due to the decreased temperature sensitivity of leaf unfolding the length of the growing season has not increased any more. These finding needs to be addressed in vegetation models used for assessing the effects of climate change. 相似文献
10.
Martina H. Stiasny Michael Sswat Felix H. Mittermayer Inger‐Britt Falk‐Petersen Nalani K. Schnell Velmurugu Puvanendran Atle Mortensen Thorsten B. H. Reusch Catriona Clemmesen 《Global Change Biology》2019,25(3):839-849
In order to understand the effect of global change on marine fishes, it is imperative to quantify the effects on fundamental parameters such as survival and growth. Larval survival and recruitment of the Atlantic cod (Gadus morhua) were found to be heavily impaired by end‐of‐century levels of ocean acidification. Here, we analysed larval growth among 35–36 days old surviving larvae, along with organ development and ossification of the skeleton. We combined CO2 treatments (ambient: 503 µatm, elevated: 1,179 µatm) with food availability in order to evaluate the effect of energy limitation in addition to the ocean acidification stressor. As expected, larval size (as a proxy for growth) and skeletogenesis were positively affected by high food availability. We found significant interactions between acidification and food availability. Larvae fed ad libitum showed little difference in growth and skeletogenesis due to the CO2 treatment. Larvae under energy limitation were significantly larger and had further developed skeletal structures in the elevated CO2 treatment compared to the ambient CO2 treatment. However, the elevated CO2 group revealed impairments in critically important organs, such as the liver, and had comparatively smaller functional gills indicating a mismatch between size and function. It is therefore likely that individual larvae that had survived acidification treatments will suffer from impairments later during ontogeny. Our study highlights important allocation trade‐off between growth and organ development, which is critically important to interpret acidification effects on early life stages of fish. 相似文献