Defects in crystalline materials have a tremendous impact on their functional behavior. Controlling and tuning of these imperfections can lead to marked improvements in their physical, electrical, ...magnetic, and optical properties. Thanks to the development of aberration‐corrected (scanning) transmission electron microscopy (STEM/TEM), direct visualization of defects at multiple length scales has now become possible, including those critically important defects at the atomic scale. Thorough understanding of the nature and dynamics of these defects is the key to unraveling the fundamental origins of structure–property relationships. Such insight can therefore allow the creation of new materials with desired properties through appropriate defect engineering. Herein, several examples of new insights obtained from representative functional materials are shown, including piezoelectrics/ferroelectrics, oxide interfaces, thermoelectrics, electrocatalysts, and 2D materials.
Direct visualization of structural defects, especially for atomic‐scale defects, and thorough understanding of their nature and dynamics, are crucial to unravel structure–property relationships. Such insights can therefore guide further property optimization through appropriate defect engineering. Two representative examples are coexisting nanophases with polarization rotation at the atomic‐scale of piezoelectrics, and atomic‐scale interstitials for simultaneously optimizing thermal and electrical transport properties in classic PbTe thermoelectric materials.
•We study the role of leader creative self-efficacy (LCSE) in follower creativity.•LCSE is positively related to leader encouragement of creativity (LEC).•Follower creative process engagement (FCPE) ...is related to follower creativity.•Leader–member exchange (LMX) strengthens the positive effect of LEC on FCPE.•LMX boosts the effect of LCSE on follower creativity via LEC and FCPE.
Creativity scholars have long called for more research on the effects of leader characteristics on employee creativity. Answering this call, this study draws on social cognitive theory to examine the effect of leader creative self-efficacy (CSE) on follower creativity. Using a sample of 544 employees nested under 106 supervisors at a large information technology company in the U.S., we obtained support for the indirect effect of leader CSE on follower creativity via leader encouragement of creativity and follower creative process engagement. In addition, follower leader–member exchange (LMX) strengthened the relationship between leader encouragement of creativity and follower creative process engagement. Thus, in the presence of higher LMX, leader CSE is likely to have a stronger positive impact on employee creativity through leader encouragement of creativity and, subsequently, follower creative process engagement. Our findings contribute to a better understanding of the role of leader attributes in employee creativity.
Rationale
While human depressive illness is indeed uniquely human, many of its symptoms may be modeled in rodents. Based on human etiology, the assumption has been made that depression-like behavior ...in rats and mice can be modulated by some of the powerful early life programming effects that are known to occur after manipulations in the first weeks of life.
Objective
Here we review the evidence that is available in literature for early life manipulation as risk factors for the development of depression-like symptoms such as anhedonia, passive coping strategies, and neuroendocrine changes. Early life paradigms that were evaluated include early handling, separation, and deprivation protocols, as well as enriched and impoverished environments. We have also included a small number of stress-related pharmacological models.
Results
We find that for most early life paradigms per se, the actual validity for depression is limited. A number of models have not been tested with respect to classical depression-like behaviors, while in many cases, the outcome of such experiments is variable and depends on strain and additional factors.
Conclusion
Because programming effects confer vulnerability rather than disease, a number of paradigms hold promise for usefulness in depression research, in combination with the proper genetic background and adult life challenges.
Radiation dose intensification improves outcome in men with high-risk prostate cancer (HR-PCa). A prospective trial was conducted to determine safety, feasibility, and maximal tolerated dose of ...multilevel magnetic resonance imaging (MRI)-based 5-fraction SABR in patients with HR-PCa.
This phase I clinical trial enrolled patients with HR-PCa with grade group ≥4, prostate-specific antigen (PSA) ≥20 ng/mL, or radiographic ≥T3, and well-defined prostatic lesions on multiparametric MRI (mpMRI) into 4 dose-escalation cohorts. The initial cohort received 47.5 Gy to the prostate, 50 Gy to mpMRI-defined intraprostatic lesion(s), and 22.5 Gy to pelvic lymph nodes in 5 fractions. Radiation doses were escalated for pelvic nodes to 25 Gy and mpMRI lesion(s) to 52.5 Gy and then 55 Gy. Escalation was performed sequentially according to rule-based trial design with 7 to 15 patients per cohort and a 90-day observation period. All men received peri-rectal hydrogel spacer, intraprostatic fiducial placement, and 2 years of androgen deprivation. The primary endpoint was maximal tolerated dose according to a 90-day acute dose-limiting toxicity (DLT) rate <33%. DLT was defined as National Cancer Institute Common Toxicity Criteria for Adverse Events ≥grade 3 treatment-related toxicity. Secondary outcomes included acute and delayed gastrointestinal (GI)/genitourinary (GU) toxicity graded with Common Toxicity Criteria for Adverse Events.
Fifty-five of the 62 enrolled patients were included in the analysis. Dose was escalated through all 4 cohorts without observing any DLTs. Median overall follow-up was 18 months, with a median follow-up of 42, 24, 12, and 7.5 months for cohorts 1 to 4 respectively. Acute and late grade 2 GU toxicities were 25% and 20%, while GI were 13% and 7%, respectively. Late grade 3 GU and GI toxicities were 2% and 0%, respectively.
SABR dose for HR-PCa was safely escalated with multilevel dose painting of 47.5 Gy to prostate, 55 Gy to mpMRI-defined intraprostatic lesions, and 25 Gy to pelvic nodal region in 5 fractions. Longer and ongoing follow-up will be required to assess late toxicity.
Evidence of the relationship of cardiovascular health (CVH), defined by the American Heart Association, and specific cardiovascular outcomes is lacking, particularly among Hispanics. This study ...sought to evaluate the relationship between the number of ideal CVH metrics and cardiovascular risk, overall and by event subtype, in a multiethnic community-based prospective cohort.
A total of 2981 subjects (mean age, 69±10 years; 54% Caribbean Hispanic, 25% black, 21% white) free of myocardial infarction and stroke at baseline in the Northern Manhattan Study were prospectively followed up (median follow-up, 11 years). The relationship between the number of ideal CVH metrics and the risk of cardiovascular disease, including myocardial infarction, stroke, and vascular death, was investigated. Overall, a strong gradient relationship was observed between the adjusted hazard ratios for cardiovascular disease and the number of ideal CVH metrics: 0.73 (95% confidence interval, 0.60-0.89), 0.61 (95% confidence interval, 0.50-0.76), 0.49 (95% confidence interval, 0.38-0.63), and 0.41 (95% confidence interval, 0.26-0.63) for those having 2, 3, 4, and 5 to 6 ideal CVH metrics, respectively, compared with those having 0 to 1 ideal CVH metrics (P for trend <0.0001). Similar graded relationships were found between the number of ideal CVH metrics and the adjusted incidence rate for each specific outcome and among whites, blacks, and Caribbean Hispanics.
Our findings demonstrated a steep gradient relationship between ideal CVH and individual cardiovascular disease end points, including stroke, that was similar for whites, blacks, and Caribbean Hispanics. This evidence supports the application of the AHA ideal cardiovascular health metrics for cardiovascular disease risk assessment and health promotion for all Americans regardless of race-ethnic background.
Ageing of the immune system, or immunosenescence, contributes to the morbidity and mortality of the elderly
. To define the contribution of immune system ageing to organism ageing, here we ...selectively deleted Ercc1, which encodes a crucial DNA repair protein
, in mouse haematopoietic cells to increase the burden of endogenous DNA damage and thereby senescence
in the immune system only. We show that Vav-iCre
;Ercc1
mice were healthy into adulthood, then displayed premature onset of immunosenescence characterized by attrition and senescence of specific immune cell populations and impaired immune function, similar to changes that occur during ageing in wild-type mice
. Notably, non-lymphoid organs also showed increased senescence and damage, which suggests that senescent, aged immune cells can promote systemic ageing. The transplantation of splenocytes from Vav-iCre
;Ercc1
or aged wild-type mice into young mice induced senescence in trans, whereas the transplantation of young immune cells attenuated senescence. The treatment of Vav-iCre
;Ercc1
mice with rapamycin reduced markers of senescence in immune cells and improved immune function
. These data demonstrate that an aged, senescent immune system has a causal role in driving systemic ageing and therefore represents a key therapeutic target to extend healthy ageing.
Differentiation between obstructive and central apneas and hypopneas requires quantitative measurement of respiratory effort (RE) using esophageal pressure (PES), which is rarely implemented. This ...study investigated whether the sleep mandibular movements (MM) signal recorded with a tri-axial gyroscopic chin sensor (Sunrise, Namur, Belgium) is a reliable surrogate of PES in patients with suspected obstructive sleep apnea (OSA).
In-laboratory polysomnography (PSG) with PES and concurrent MM monitoring was performed. PSGs were scored manually using AASM 2012 rules. Data blocks (n=8042) were randomly sampled during normal breathing (NB), obstructive or central apnea/hypopnea (OA/OH/CA/CH), respiratory effort-related arousal (RERA), and mixed apnea (MxA). Analyses were evaluation of the similarity and linear correlation between PES and MM using the longest common subsequence (LCSS) algorithm and Pearson's coefficient; description of signal amplitudes; estimation of the marginal effect for crossing from NB to a respiratory disturbance for a given change in MM signal using a mixed linear-regression.
Participants (n=38) had mild to severe OSA (median AH index 28.9/h; median arousal index 23.2/h). MM showed a high level of synchronization with concurrent PES signals. Distribution of MM amplitude differed significantly between event types: median (95% confidence interval) values of 0.60 (0.16-2.43) for CA, 0.83 (0.23-4.71) for CH, 1.93 (0.46-12.43) for MxA, 3.23 (0.72-18.09) for OH, and 6.42 (0.88-26.81) for OA. Mixed regression indicated that crossing from NB to central events would decrease MM signal amplitude by -1.23 (CH) and -2.04 (CA) units, while obstructive events would increase MM amplitude by +3.27 (OH) and +6.79 (OA) units (all p<10
).
In OSA patients, MM signals facilitated the measurement of specific levels of RE associated with obstructive, central or mixed apneas and/or hypopneas. A high degree of similarity was observed with the PES gold-standard signal.
We predict a new type of two- and three-dimensional stable quantum droplets persistently rotating in broad external two-dimensional and weakly anharmonic potential. Their evolution is described by ...the system of the Gross-Pitaevskii equations with Lee-Huang-Yang quantum corrections. Such droplets resemble whispering-gallery modes localized in the polar direction due to nonlinear interactions and, depending on their chemical potential and rotation frequency, they appear in rich variety of shapes, ranging from nearly flat-top or strongly localized rotating wave packets, to crescentlike objects extending nearly over the entire range of polar angles. Above critical rotation frequency quantum droplets transform into vortex droplets (in two dimensions) or vortex tori (in three dimensions), whose topological charge gradually increase with the increase of the modulus of chemical potential, and therefore they belong to the family of nonlinear modes connecting fundamental and vortex quantum droplets. Rotating quantum droplets are exceptionally robust objects, stable practically in the entire range of their existence.
As an alternative technology to energy intensive distillations, adsorptive separation by porous solids offers lower energy cost and higher efficiency. Herein we report a topology-directed design and ...synthesis of a series of Zr-based metal-organic frameworks with optimized pore structure for efficient separation of C6 alkane isomers, a critical step in the petroleum refining process to produce gasoline with high octane rating. Zr
O
(OH)
(bptc)
adsorbs a large amount of n-hexane but excluding branched isomers. The n-hexane uptake is ~70% higher than that of a benchmark adsorbent, zeolite-5A. A derivative structure, Zr
O
(OH)
(H
O)
(abtc)
, is capable of discriminating all three C6 isomers and yielding a high separation factor for 3-methylpentane over 2,3-dimethylbutane. This property is critical for producing gasoline with further improved quality. Multicomponent breakthrough experiments provide a quantitative measure of the capability of these materials for separation of C6 alkane isomers. A detailed structural analysis reveals the unique topology, connectivity and relationship of these compounds.
The interface heat transfer of two layers induced by van der Waals (vdW) contacts is theoretically investigated, based on first-principles calculations at low temperatures. The results suggest that ...out-of-plane acoustic phonons with low frequencies dominate the interface thermal transport due to the vdW interaction. The interface thermal conductivity is proportional to the cubic of temperature at very low temperatures, but becomes linearly proportional to temperature as temperature increases. We show that manipulating the strain alters vdW coupling, leading to increased interfacial thermal conductivity at the interface. Our findings provide valuable insights into the interface heat transport in vdW heterostructures and support further design and optimization of electronic and optoelectronic nanodevices based on vdW contacts.
The heat transfer induced by van der Waals contacts is dominated by ZA phonons. The interface thermal conductivity is proportional to the cubic of temperature, but becomes linearly proportional to temperature as temperature increases.
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