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Black phosphorus (BP) has gained renewed attention due to its singular anisotropic electronic and optical properties that might be exploited for a wide range of technological applications. In this respect, the thermal properties are particularly important both to predict its room temperature operation and to determine its thermoelectric potential. From this point of view, one of the most spectacular and poorly understood phenomena is indeed the BP temperature-induced band gap opening; when temperature is increased, the fundamental band gap increases instead of decreases. This anomalous thermal dependence has also been observed recently in its monolayer counterpart. In this work, based on ab initio calculations, we present an explanation for this long known and yet not fully explained effect. We show that it arises from a combination of harmonic and lattice thermal expansion contributions, which are in fact highly interwined. We clearly narrow down the mechanisms that cause this gap opening by identifying the peculiar atomic vibrations that drive the anomaly. The final picture we give explains both the BP anomalous band gap opening and the frequency increase with increasing volume (tension effect).

Haematopoiesis is a developmental cascade that generates all blood cell lineages in health and disease. This process relies on quiescent haematopoietic stem cells capable of differentiating, self renewing and expanding upon physiological demand. However, the mechanisms that regulate haematopoietic stem cell homeostasis and function remain largely unknown. Here we show that the neurotrophic factor receptor RET (rearranged during transfection) drives haematopoietic stem cell survival, expansion and function. We find that haematopoietic stem cells express RET and that its neurotrophic factor partners are produced in the haematopoietic stem cell environment. Ablation of Ret leads to impaired survival and reduced numbers of haematopoietic stem cells with normal differentiation potential, but loss of cell-autonomous stress response and reconstitution potential. Strikingly, RET signals provide haematopoietic stem cells with critical Bcl2 and Bcl2l1 surviving cues, downstream of p38 mitogen-activated protein (MAP) kinase and cyclic-AMP-response element binding protein (CREB) activation. Accordingly, enforced expression of RET downstream targets, Bcl2 or Bcl2l1, is sufficient to restore the activity of Ret null progenitors in vivo. Activation of RET results in improved haematopoietic stem cell survival, expansion and in vivo transplantation efficiency. Remarkably, human cord-blood progenitor expansion and transplantation is also improved by neurotrophic factors, opening the way for exploration of RET agonists in human haematopoietic stem cell transplantation. Our work shows that neurotrophic factors are novel components of the haematopoietic stem cell microenvironment, revealing that haematopoietic stem cells and neurons are regulated by similar signals.

Age‐related DNA damage is regarded as one of the possible explanations of aging. Although a generalized idea about the accumulation of DNA damage with age exists, results found in the literature are inconsistent. To better understand the question of age‐related DNA damage in humans and to identify possible moderator variables, a metaanalysis was conducted. Electronic databases and bibliographies for studies published since 2004 were searched. Summary odds ratios (ORs) and 95% confidence intervals (CIs) for age‐related DNA damage were calculated in a random‐effects model. A total of 76 correlations from 36 studies with 4676 participants were included. Based on our analysis, a correlation between age and DNA damage was found (r=0.230, p=0.000; 95% confidence interval=0.111‐0.342). The test for heterogeneity of variance indicates that the study´s results are significantly high (Q (75)=1754.831, p=0.000). Moderator variables such as smoking habits, technique used, and the tissue/sample analyzed, are shown to influence age‐related DNA damage (p=0.026; p=0.000; p=0.000, respectively). Nevertheless, sex did not show any influence on this relation (p=0.114). In conclusion, this meta‐analysis showed an association between age and DNA damage in humans. It was also found that smoking habits, the technique used, and tissue/sample analyzed, are important moderator variables in age‐related DNA damage.

This study aims to describe the daily physical activity (PA) of a sample of adults over the course of 1 year and to examine if there are any changes in achieving PA recommendations when assessed at different periods of the year. Participants, 257 women (age: 58.99 ± 18.93 years, BMI: 26.75 ± 4.57 kg m(-2)) and 178 men (age: 49.22 ± 20.39 years, BMI: 26.81 ± 3.51 kg m(-2)), wore an accelerometer 4-7 days. Periods of data collection were defined as T1 (September to December), T2 (January to April) and T3 (May to July). From T1 and T2, men from 20 to 39 years significantly increased values of daily average ct.min(-1) (U = 506, p = 0.012), due to an increase in moderate-to-vigorous PA by 15.96 min (U = 455, p = 0.003). Achievement of the two PA recommendations varied throughout the year and among the gender/age groups. Results from this study showed that women generally maintain their level of PA throughout the year, whereas men show some variation, and that there are periods of the year when individuals are more likely to be involved in PA, or perform lower-intensity activities, especially older age groups. Also, recommendations of minimum PA are not accomplished in a constant way throughout the year. PA interventions should be conducted while being mindful of the time of year in which they will take place in order to help maintain a consistent PA level throughout the year to ensure health benefits from PA.

Background: Systematic studies of the efficacy of Narrative Therapy (NT) for depression are sparse., Objective: To evaluate the efficacy of individual NT for moderate depression in adults compared to Cognitive-Behavioral Therapy (CBT)., Method: Sixty-three depressed clients were assigned to either NT or CBT. The Beck Depression Inventory-II (BDI-II) and Outcome Questionnaire-45.2 (OQ-45.2) were used as outcome measures., Results: We found a significant symptomatic reduction in both treatments. Group differences favoring CBT were found on the BDI-II, but not on the OQ-45.2., Conclusions: Pre- to post-treatment effect sizes for completers in both groups were superior to benchmarked waiting-list control groups.

Self-multiplicity is a widely recognized phenomenon within psychology. The study of how self-continuity emerges amidst self-multiplicity remains a crucial issue, however. Dialogical approaches are widely viewed as suitable for developing this field of study but they demand coherent methods compatible with their theoretical bases. After reviewing the available methods for the study of the dialogical self, as well as other dialogical methods for the study of psychotherapy, we conclude that we still lack a method which can be used by external observers and is devoted to the systematic tracing of the dialogical dynamics of self-positions as they unfold over time. A new method, positioning microanalysis, is described in detail as a possible way to overcome current limitations in methods focused on the dialogicality inherent in selfhood processes. Positioning microanalysis takes a genetic-developmental perspective on dialogical processes in the self and allows for the depiction of microgenetic movements of self-positions over time and the establishment of more or less stable sequences or patterns of positions. This is illustrated by its application to an emotion-focused therapy session.

Objective: To review the use of accelerometry as an objective measure of physical activity in adults and elderly people., Methods: A systematic review of studies on the use of accelerometty as an objective measure to assess physical activity in adults were examined in PubMed Central, Web of Knowledge, EBSCO and Medline databases from March 29 to April 15, 2010. The following keywords were used: "accelerometry," "accelerometer," "physical activity," "PA," "patterns," "levels," "adults," "older adults," and "elderly," either alone or in combination using "AND" or "OR." The reference lists of the articles retrieved were examined to capture any other potentially relevant article. Of 899 studies initially identified, only 18 were fully reviewed, and their outcome measures abstracted and analyzed., Results: Eleven studies were conducted in North America (United States), five in Europe, one in Africa (Cameroon) and one in Australia. Very few enrolled older people, and only one study reported the season or time of year when data was collected. The articles selected had different methods, analyses, and results, which prevented comparison between studies., Conclusions: There is a need to standardize study methods for data reporting to allow comparisons of results across studies and monitor changes in populations. These data can help design more adequate strategies for monitoring and promotion of physical activity.

This study aims to further the understanding of how innovative moments (IMs), which are exceptions to a client's problematic self-narrative in the therapy dialogue, progress to the construction of a new self-narrative, leading to successful psychotherapy. The authors' research strategy involved tracking IMs, and the themes expressed therein (or protonarratives), and analysing the dynamic relation between IMs and protonarratives within and across sessions using state space grids in a good-outcome case of constructivist psychotherapy. The concept of protonarrative helped explain how IMs transform a problematic self-narrative into a new, more flexible, self-narrative. The increased flexibility of the new self-narrative was manifested as an increase in the diversity of IM types and of protonarratives. Results suggest that new self-narratives may develop through the elaboration of protonarratives present in IMs, yielding an organizing framework that is more flexible than the problematic self-narrative.