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1.
The transdiagnostic expression of psychotic experiences in common mental disorder (anxiety/depression/substance use disorder) is associated with a poorer prognosis, and a small minority of people may indeed develop a clinical picture that meets criteria for schizophrenia. However, it appears neither useful nor valid to observe early states of multidimensional psychopathology in young people through the “schizo”‐prism, and apply misleadingly simple, unnecessary and inefficient binary concepts of “risk” and “transition”. A review of the “ultra‐high risk” (UHR) or “clinical high risk” (CHR) literature indicates that UHR/CHR samples are highly heterogeneous and represent individuals diagnosed with common mental disorder (anxiety/depression/substance use disorder) and a degree of psychotic experiences. Epidemiological research has shown that psychotic experiences are a (possibly non‐causal) marker of the severity of multidimensional psychopathology, driving poor outcome, yet notions of “risk” and “transition” in UHR/CHR research are restrictively defined on the basis of positive psychotic phenomena alone, ignoring how baseline differences in multidimensional psychopathology may differentially impact course and outcome. The concepts of “risk” and “transition” in UHR/CHR research are measured on the same dimensional scale, yet are used to produce artificial diagnostic shifts. In fact, “transition” in UHR/CHR research occurs mainly as a function of variable sample enrichment strategies rather than the UHR/CHR “criteria” themselves. Furthermore, transition rates in UHR/CHR research are inflated as they do not exclude false positives associated with the natural fluctuation of dimensional expression of psychosis. Biological associations with “transition” thus likely represent false positive findings, as was the initial claim of strong effects of omega‐3 polyunsatured fatty acids in UHR samples. A large body of UHR/CHR intervention research has focused on the questionable outcome of “transition”, which shows lack of correlation with functional outcome. It may be more productive to consider the full range of person‐specific psychopathology in all young individuals who seek help for mental health problems, instead of “policing” youngsters for the transdiagnostic dimension of psychosis. Instead of the relatively inefficient medical high‐risk approach, a public health perspective, focusing on improved access to a low‐stigma, high‐hope, small scale and youth‐specific environment with acceptable language and interventions may represent a more useful and efficient strategy.  相似文献   

2.
In this review, we focus on strategies for designing functional nano gene carriers, as well as choosing therapeutic genes targeting the tumor microenvironment. Gene mutations have a great impact on the occurrence of cancer. Thus, gene therapy plays a major role in cancer therapy and has the potential to cure cancer. Well‐designed gene therapy largely relies on effective gene carriers, which can be divided into viral carriers and non‐viral carriers. A gene carrier delivers functional genes to their intracellular target and avoids nucleic acids being degraded by nucleases in the serum. Most conventional cancer gene therapies only target cancer cells and do not appear to be sufficintly efficient to pass clinical trials. Accumulating evidence has shown that extending the therapeutic strategies to the tumor microenvironment, rather than the tumor cell itself, can allow more options for achieving robust anti‐cancer efficiency. In addition, unusual features between tumor microenvironment and normal tissues, such as a lower pH, higher glutathione and reactive oxygen species concentrations, and overexpression of some enzymes, facilitate the design of smart stimuli‐responsive gene carriers regulated by the tumor microenvironment. These carriers interact with nucleic acids and then form stable nanoparticles under physiological conditions. By regulation of the tumor microenvironment, stimuli‐responsive gene carriers are able to change their properties and achieve high gene delivery efficiency. Considering the tumor microenvironment as the “regulator” and “target” when designing gene carriers and choosing therapeutic genes shows significant benefit with respect to improving the accuracy and efficiency of cancer gene therapy.  相似文献   

3.
Eating behavior can be influenced by the rewarding value of food, i.e., “liking” and “wanting.” The objective of this study was to assess in normal‐weight dietary restrained (NR) vs. unrestrained (NU) eaters how rewarding value of food is affected by satiety, and by eating a nonhealthy perceived, dessert‐specific food vs. a healthy perceived, neutral food (chocolate mousse vs. cottage cheese). Subjects (24NR age = 25.0 ± 8.2 years, BMI = 22.3 ± 2.1 kg/m2; 26NU age = 24.8 ± 8.0 years, BMI = 22.1 ± 1.7 kg/m2) came to the university twice, fasted (randomized crossover design). Per test‐session “liking” and “wanting” for 72 items divided in six categories (bread, filling, drinks, dessert, sweets, stationery (placebo)) was measured, before and after consumption of chocolate mousse/cottage cheese, matched for energy content (5.6 kJ/g) and individual daily energy requirements (10%). Chocolate mousse was liked more than cottage cheese (P < 0.05). After consumption of chocolate mousse or cottage cheese, appetite and “liking” vs. placebo were decreased in NR and NU (P < 0.03), whereas “wanting” was only decreased in NR vs. NU (P ≤ 0.01). In NR vs. NU “wanting” was specifically decreased after chocolate mousse vs. cottage cheese; this decrease concerned especially “wanting” for bread and filling (P < 0.05). To conclude, despite similar decreases in appetite and “liking” after a meal in NR and NU, NR decrease “wanting” in contrast to NU. NR decrease “wanting” specifically for a nonhealthy perceived, “delicious,” dessert‐specific food vs. a nutritional identical, yet healthy perceived, slightly less “delicious,” “neutral” food. A healthy perceived food may thus impose greater risk for control of energy intake in NR.  相似文献   

4.
150 years “Biogenetic Law” The zoologist Ernst Haeckel is one of the most well‐known, but also one of the most controversial scientists of the late 19th and early 20th centuries. He was one of the earliest Darwinists and a forceful advocate of evolutionary theory. Together with “Darwin's Bulldog” Thomas Henry Huxley, Haeckel was a central figure in the early history and popularization of Darwinism. But his name is not only a symbol for the disputes about the theory of evolution and its popularization, but also for a campaign for monism, a world‐view or philosophy created by Haeckel himself. Together with Fritz Müller, Ernst Haeckel was one of the first to formulate a “Biogenetic Law”. He also created several concepts and terms still in use in biology today, such as “ontogeny”, “phylogeny”, “ecology”, “cholorogy” and “phylum” in his first, and maybe most important book “General Morphology of Organism”, which was published in 1866, 150 years ago.  相似文献   

5.
A key goal of aging research was to understand mechanisms underlying healthy aging and develop methods to promote the human healthspan. One approach is to identify gene regulations unique to healthy aging compared with aging in the general population (i.e., “common” aging). Here, we leveraged Genotype‐Tissue Expression (GTEx) project data to investigate “healthy” and “common” aging gene expression regulations at a tissue level in humans and their interconnection with diseases. Using GTEx donors' disease annotations, we defined a “healthy” aging cohort for each tissue. We then compared the age‐associated genes derived from this cohort with age‐associated genes from the “common” aging cohort which included all GTEx donors; we also compared the “healthy” and “common” aging gene expressions with various disease‐associated gene expressions to elucidate the relationships among “healthy,” “common” aging and disease. Our analyses showed that 1. GTEx “healthy” and “common” aging shared a large number of gene regulations; 2. Despite the substantial commonality, “healthy” and “common” aging genes also showed distinct function enrichment, and “common” aging genes had a higher enrichment for disease genes; 3. Disease‐associated gene regulations were overall different from aging gene regulations. However, for genes regulated by both, their regulation directions were largely consistent, implying some aging processes could increase the susceptibility to disease development; and 4. Possible protective mechanisms were associated with some “healthy” aging gene regulations. In summary, our work highlights several unique features of GTEx “healthy” aging program. This new knowledge could potentially be used to develop interventions to promote the human healthspan.  相似文献   

6.
Understanding changes in biodiversity requires the implementation of monitoring programs encompassing different dimensions of biodiversity through varying sampling techniques. In this work, fish assemblages associated with the “outer” and “inner” sides of four marinas, two at the Canary Islands and two at southern Portugal, were investigated using three complementary sampling techniques: underwater visual censuses (UVCs), baited cameras (BCs), and fish traps (FTs). We firstly investigated the complementarity of these sampling methods to describe species composition. Then, we investigated differences in taxonomic (TD), phylogenetic (PD) and functional diversity (FD) between sides of the marinas according to each sampling method. Finally, we explored the applicability/reproducibility of each sampling technique to characterize fish assemblages according to these metrics of diversity. UVCs and BCs provided complementary information, in terms of the number and abundances of species, while FTs sampled a particular assemblage. Patterns of TD, PD, and FD between sides of the marinas varied depending on the sampling method. UVC was the most cost‐efficient technique, in terms of personnel hours, and it is recommended for local studies. However, for large‐scale studies, BCs are recommended, as it covers greater spatio‐temporal scales by a lower cost. Our study highlights the need to implement complementary sampling techniques to monitor ecological change, at various dimensions of biodiversity. The results presented here will be useful for optimizing future monitoring programs.  相似文献   

7.
Seed for restoration projects has traditionally been sourced locally to “preserve” the genetic integrity of the replanted site. Plants grown from locally sourced seeds are perceived to have the advantage of being adapted to local conditions, and the use of local provenance is a requirement of many restoration projects. However, the processes of climate change and habitat fragmentation, with the subsequent development of novel environments, are forcing us to reconsider this basic tenet of restoration ecology. We tested the “local provenance is best” paradigm, by comparing the performance of plants grown from local with non‐local seed sources within a common garden experiment. We selected six species representing a range of growth forms (Acacia falcata, Bursaria spinosa ssp. spinosa, Eucalyptus crebra, E. tereticornis, Hardenbergia violacea and Themeda australis) from an assemblage known as the Cumberland Plain Woodland, a threatened community in western Sydney. Multiple provenances were collected from within the range of each species and grown at two field sites on the Cumberland Plain. Growing time varied between species and ranged from 7 months to 2 years. With the exception of B. spinosa, and to a lesser extent T. australis, we found little evidence that local provenance plants were superior to distant provenances in terms of survival and establishment.  相似文献   

8.
The United Nations (UN) Convention on the Rights of Persons with Disabilities (CRPD) is the most up‐to‐date international legal instrument concerning the rights of persons with disabilities. Such persons are taken to include those with serious mental disorders. According to an authoritative interpretation of a crucial Article (Article 12 ‐ Equal recognition before the law) by the UN CRPD Committee, involuntary detention and treatment of people with mental health disabilities are prohibited under the Convention. Both conventional mental health law and “capacity‐based” law are deemed to violate the Convention. However, some other UN bodies are not in full agreement (for example, the UN Human Rights Committee and the Subcommittee on Prevention of Torture and Other Cruel, Inhuman or Degrading Treatment or Punishment), while others are less explicitly absolutist (for example, the Human Rights Council). Furthermore, strong criticisms of the position of the CRPD Committee have been mounted from a number of academic quarters. These criticisms center on whether the role of a person's ability to make a decision can be ignored, no matter the circumstances. Much of the above debate turns on the concept of “legal capacity” and the now often‐repeated precept that one must always respect the “will and preferences” of the person with a disability. However, “will and preferences” remains undefined. In this paper, I offer an analysis of “will and preferences” that can clarify interventions that may be acceptable or non‐acceptable under the terms of the UN Convention.  相似文献   

9.
10.
There is an intensive search for heterogeneous single atom catalysts (SACs) of high activity, efficiency, durability, and selectivity for a wide variety of electrocatalytic conversion and chemical reactions, such as the hydrogen evolution reaction (HER), oxygen evolution/reduction reaction (OER and ORR), CO2 reduction reaction (CO2 RR), and nitrogen reduction reaction (NRR). With the downsizing from nanoparticles and clusters to single atoms, there are steady changes in the bond and coordination environment for each and every atom involved. Indeed, the single atoms in these electrocatalysts are not “singles”; they are “married” to the supporting surfaces, and their performance is controlled by the bonding and coordination with the substrate surfaces. Herein, an overview is presented on the brief history leading to the rapid development of SACs and their current status, by focusing on their synthesis, control of composition, strategies to realize single atoms with the desired bonds and coordination, and targeted performance in selected reactions. Their applications in the selected spectrum of energy conversion and chemical reactions are discussed, in relation to their structures at varying length scales down to the atomic level. A particular emphasis is placed on on‐going research activities, together with the future perspectives and particular challenges for SACs.  相似文献   

11.
Public works programs have been posited as win–win solutions for achieving societal goals for ecological restoration and poverty alleviation. However, little is documented regarding the challenges of implementing such projects. A commonly cited example is South Africa's invasive alien plant control program “Working for Water” (WfW), which aims to create employment via restoring landscapes invaded with alien plants. Recent studies have raised questions over the effectiveness of this program in achieving both its restoration and poverty alleviation goals. This is the first study that we are aware of that synthesizes the knowledge of managers on both the poverty alleviation and environmental outcomes of a public works project. Herein, we sought to understand the challenges and constraints faced by 23 WfW managers in fulfilling the program's environmental and poverty alleviation objectives. We found that the challenges most frequently cited by managers related to the capacity and competence of managers and teams, followed by challenges relating to planning and coordination, specifically the challenges of being flexible and adaptive when constrained by operating procedures. In addition, the current focus on maximizing short‐term employment was perceived by some as limiting the efficiency and long‐term effectiveness of the WfW program in achieving its environmental and social goals. We suggest that improving the conditions and duration of employment could improve the effectiveness of invasive alien plant control and ecological outcomes. We also suggest that WfW measure the impacts of their interventions through an adaptive management approach so that it can learn and adapt to the challenges it faces.  相似文献   

12.
Since 1989, efforts to understand the nature of interfirm resource sharing in the form of industrial symbiosis and to replicate in a deliberate way what was largely self‐organizing in Kalundborg, Denmark have followed many paths, some with much success and some with very little. This article provides a historical view of the motivations and means for pursuing industrial symbiosis—defined to include physical exchanges of materials, energy, water, and by‐products among diversified clusters of firms. It finds that “uncovering” existing symbioses has led to more sustainable industrial development than attempts to design and build eco‐industrial parks incorporating physical exchanges. By examining 15 proposed projects brought to national and international attention by the U.S. President's Council on Sustainable Development beginning in the early 1990s, and contrasting these with another 12 projects observed to share more elements of self‐organization, recommendations are offered to stimulate the identification and uncovering of already existing “kernels” of symbiosis. In addition, policies and practices are suggested to identify early‐stage precursors of potentially larger symbioses that can be nurtured and developed further. The article concludes that environmentally and economically desirable symbiotic exchanges are all around us and now we must shift our gaze to find and foster them.  相似文献   

13.
14.
H. Kokko 《Ecology letters》2001,4(4):322-326
“Good genes” models of mate choice are commonly tested by examining whether attractive males sire offspring with improved survival. If offspring do not survive better (or indeed survive less well), but instead inherit the attractiveness of their father, results are typically interpreted to support the Fisherian process, which allows the evolution of preferences for arbitrary traits. Here, I show that the above view is mistaken. Because of life‐history trade‐offs, an attractive male may perform less well in other components of fitness. A female obtains a “good genes” benefit whenever males show heritable variation in quality, even if high‐quality males invest so much in sexual advertisement that attractiveness has no positive correlation with any other life‐history trait than male mating success itself. Therefore, a negative correlation between attractiveness and viability does not falsify good genes, if mating with a high‐quality male results on average in superior offspring performance (mating success of sons included). The heritable “good genes” benefit can be sustained even if sexually antagonistic genes cause female offspring sired by high‐quality males to survive and reproduce less well. Neglecting the component of male mating success from measurements of fitness returns from sons and daughters will bias the advantage of mating with a high‐quality male downwards. This result may partly account for the rather weak “good genes” effects found in a recent meta‐analysis.  相似文献   

15.
The “at risk mental state” for psychosis approach has been a catalytic, highly productive research paradigm over the last 25 years. In this paper we review that paradigm and summarize its key lessons, which include the valence of this phenotype for future psychosis outcomes, but also for comorbid, persistent or incident non‐psychotic disorders; and the evidence that onset of psychotic disorder can at least be delayed in ultra high risk (UHR) patients, and that some full‐threshold psychotic disorder may emerge from risk states not captured by UHR criteria. The paradigm has also illuminated risk factors and mechanisms involved in psychosis onset. However, findings from this and related paradigms indicate the need to develop new identification and diagnostic strategies. These findings include the high prevalence and impact of mental disorders in young people, the limitations of current diagnostic systems and risk identification approaches, the diffuse and unstable symptom patterns in early stages, and their pluripotent, transdiagnostic trajectories. The approach we have recently adopted has been guided by the clinical staging model and adapts the original “at risk mental state” approach to encompass a broader range of inputs and output target syndromes. This approach is supported by a number of novel modelling and prediction strategies that acknowledge and reflect the dynamic nature of psychopathology, such as dynamical systems theory, network theory, and joint modelling. Importantly, a broader transdiagnostic approach and enhancing specific prediction (profiling or increasing precision) can be achieved concurrently. A holistic strategy can be developed that applies these new prediction approaches, as well as machine learning and iterative probabilistic multimodal models, to a blend of subjective psychological data, physical disturbances (e.g., EEG measures) and biomarkers (e.g., neuroinflammation, neural network abnormalities) acquired through fine‐grained sequential or longitudinal assessments. This strategy could ultimately enhance our understanding and ability to predict the onset, early course and evolution of mental ill health, further opening pathways for preventive interventions.  相似文献   

16.
Sexual dichromatism is widespread among animals, but examples of “reverse” sexual dichromatism, in which females are more brightly colored than males, are extremely rare. We discovered a unique case of reverse sexual dichromatism in the golden rocket frog (Anomaloglossus beebei), a diurnal Neotropical frog. Females are bright “golden” in color, and males are drab tan with brown pigmentation that darkens when they are calling. Here, we document this color variation with calibrated digital photography and further show that there is no evidence for sex‐specific habitat matching; both sexes live in the same well‐lit habitat on green bromeliad leaves. Our results suggest that color variation in this species is an intraspecific signal and provide an important exception to the general expectation that males are more visually conspicuous in species with conventional sex roles.  相似文献   

17.
  1. Animal behavior is elicited, in part, in response to external conditions, but understanding how animals perceive the environment and make the decisions that bring about these behavioral responses is challenging.
  2. Animal heads often move during specific behaviors and, additionally, typically have sensory systems (notably vision, smell, and hearing) sampling in defined arcs (normally to the front of their heads). As such, head‐mounted electronic sensors consisting of accelerometers and magnetometers, which can be used to determine the movement and directionality of animal heads (where head “movement” is defined here as changes in heading [azimuth] and/or pitch [elevation angle]), can potentially provide information both on behaviors in general and also clarify which parts of the environment the animals might be prioritizing (“environmental framing”).
  3. We propose a new approach to visualize the data of such head‐mounted tags that combines the instantaneous outputs of head heading and pitch in a single intuitive spherical plot. This sphere has magnetic heading denoted by “longitude” position and head pitch by “latitude” on this “orientation sphere” (O‐sphere).
  4. We construct the O‐sphere for the head rotations of a number of vertebrates with contrasting body shape and ecology (oryx, sheep, tortoises, and turtles), illustrating various behaviors, including foraging, walking, and environmental scanning. We also propose correcting head orientations for body orientations to highlight specific heading‐independent head rotation, and propose the derivation of O‐sphere‐metrics, such as angular speed across the sphere. This should help identify the functions of various head behaviors.
  5. Visualizations of the O‐sphere provide an intuitive representation of animal behavior manifest via head orientation and rotation. This has ramifications for quantifying and understanding behaviors ranging from navigation through vigilance to feeding and, when used in tandem with body movement, should provide an important link between perception of the environment and response to it in free‐ranging animals.
  相似文献   

18.
Like many economic exchanges, industrial symbiosis (IS) is thought to be influenced by social relationships and shared norms among actors in a network. While many implicit references to social characteristics exist throughout the literature, there have been few explicit attempts to operationalize and measure the concepts. The “short mental distance,”“trust,”“openness,” and “communication” recorded among managers in Kalundborg, Denmark, set a precedent for examining and encouraging social interactions among key personnel in the dozens of eco‐industrial networks around the world. In this article we explore the relationships among various aspects of social embeddedness, social capital, and IS. We develop a conceptual framework and an approach using quantitative and qualitative methods to identify and measure these social characteristics, including social network structure, communication, and similarities in norms and conceptions of waste, and apply them in an industrial network in Nanjangud, South India. The findings suggest that there is a fairly high level of shared norms about dealing with waste—the “short mental distance”—in this network, but by‐product transactions are only weakly correlated with the structure and content of communication among managers. Replication of this approach can increase the understanding and comparability of the role of social characteristics in eco‐industrial activities around the world.  相似文献   

19.
Within the Asteridae (“Sympetalae Tetracyclicae”) two main developmental patterns can be distinguished as regards the formation of corolla tubes, namely “early” and “late sympetaly”. Since the character “ontogeny of sympetaly”, after intensive studies, proved to be valuable for systematic considerations, we now recognize two blocks of orders within the Asteridae (and related groups): the Asteridae A-block and the Asteridae B-block (Figs. 82 and 83). By and large this bipartition referring mainly to the corolla tube development corresponds well with major lineages indentified by recent molecular data (see, e.g., Chase et al., 1993). Asteridae A-block is characterized predominantely by “late sympetaly” the “early sympetaly” in Rubiales and Oleales can be interpreted as derived within this block or can be linked with that in Asteridae B-block. Asteridae B-block is uniform throughout in its “early sympetaly”. In this block it is a primitive character, as judged from its occasional occurrence in the choripetalous Cornales and Apiales (Apiaceae, Araliaceae, Pittosporaceae), which can be regarded as ancestral for block B.  相似文献   

20.
Abstract The ecology and evolutionary biology of insect–plant associations has realized extensive attention, especially during the past 60 years. The classifications (categorical designations) of continuous variation in biodiversity, ranging from global patterns (e.g., latitudinal gradients in species richness/diversity and degree of herbivore feeding specialization) to localized insect–plant associations that span the biospectrum from polyphenisms, polymorphisms, biotypes, demes, host races, to cryptic species, remain academically contentious. Semantic and biosystematic (taxonomical) disagreements sometimes detract from more important ecological and evolutionary processes that drive diversification, the dynamics of gene flow and local extinctions. This review addresses several aspects of insect specialization, host‐associated divergence and ecological (including “hybrid”) speciation, with special reference to the climate warming impacts on species borders of hybridizing swallowtail butterflies (Papilionidae). Interspecific hybrid introgression may result in collapse of multi‐species communities or increase species numbers via homoploid hybrid speciation. We may see diverging, merging, or emerging genotypes across hybrid zones, all part of the ongoing processes of evolution. Molecular analyses of genetic mosaics and genomic dynamics with “divergence hitchhiking”, combined with ecological, ethological and physiological studies of “species porosity”, have already begun to unveil some answers for some important ecological/evolutionary questions. (i) How rapidly can host‐associated divergence lead to new species (and why doesn't it always do so, e.g., resulting in “incomplete” speciation)? (ii) How might “speciation genes” function, and how/where would we find them? (iii) Can oscillations from specialists to generalists and back to specialists help explain global diversity in herbivorous insects? (iv) How could recombinant interspecific hybridization lead to divergence and speciation? From ancient phytochemically defined angiosperm affiliations to recent and very local geographical mosaics, the Papilionidae (swallowtail butterflies) have provided a model for enhanced understanding of ecological patterns and evolutionary processes, including host‐associated genetic divergence, genomic mosaics, genetic hitchhiking and sex‐linked speciation genes. Apparent homoploid hybrid speciation in Papilio appears to have been catalyzed by climate warming‐induced interspecific introgression of some, but not all, species diagnostic traits, reflecting strong divergent selection (discordant), especially on the Z (= X) chromosome. Reproductive isolation of these novel recombinant hybrid genotypes appears to be accomplished via a delayed post‐diapause emergence or temporal isolation, and is perhaps aided by the thermal landscape. Changing thermal landscapes appear to have created (and may destroy) novel recombinant hybrid genotypes and hybrid species.  相似文献   

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