One major factor limiting the efficiency in organic solar cells (OSCs) is the low open-circuit voltage (V oc). Existing theoretical studies link the V oc with the charge transfer (CT) state and ...nonradiative recombination. However, also morphology and energetic disorder can have a strong impact on the V oc within realistic bulk-heterojunction OSCs. In this work, we present a kinetic Monte Carlo study on the role of the energetic disorder on the maximum V oc. We compute the quasi-Fermi level splitting for different energetic disorder and analyze the impact of the energetic disorder at the donor–acceptor interface as well as correlations in the site energies on the V oc. Our results show that the interface strongly controls the maximum V oc. For a higher interface disorder, charge densities and nongeminate recombination increase and the V oc is reduced. Furthermore, the correlated morphologies show an increase in the maximum V oc and a reduced impact of the energetic disorder.
Dissecting the cellular signaling that governs the motility of eukaryotic cells is one of the fundamental tasks of modern cell biology, not only because of the large number of physiological processes ...in which cell migration is crucial, but even more so because of the pathological ones, in particular tumor invasion and metastasis. Cell migration requires the coordination of at least four major processes: polarization of intracellular signaling, regulation of the actin cytoskeleton and membrane extension, focal adhesion and integrin signaling and contractile forces generation and rear retraction. Among the molecular components involved in the regulation of locomotion, the phosphatidylinositol-3-kinase (PI3K) pathway has been shown to exert fundamental role. A pivotal node of such pathway is represented by the serine/threonine kinase 3-phosphoinositide-dependent protein kinase-1 (PDPK1 or PDK1). PDK1, and the majority of its substrates, belong to the AGC family of kinases (related to c
MP-dependent protein kinase 1, cyclic
uanosine monophosphate-dependent protein kinase and protein kinase
), and control a plethora of cellular processes, downstream either to PI3K or to other pathways, such as RAS GTPase-MAPK (mitogen-activated protein kinase). Interestingly, PDK1 has been demonstrated to be crucial for the regulation of each step of cell migration, by activating several proteins such as protein kinase B/Akt (PKB/Akt), myotonic dystrophy-related CDC42-binding kinases alpha (MRCKα), Rho associated coiled-coil containing protein kinase 1 (ROCK1), phospholipase C gamma 1 (PLCγ1) and β3 integrin. Moreover, PDK1 regulates cancer cell invasion as well, thus representing a possible target to prevent cancer metastasis in human patients. The aim of this review is to summarize the various mechanisms by which PDK1 controls the cell migration process, from cell polarization to actin cytoskeleton and focal adhesion regulation, and finally, to discuss the evidence supporting a role for PDK1 in cancer cell invasion and dissemination.
Over the last years the zebrafish imposed itself as a powerful model to study skeletal diseases, but a limit to its use is the poor characterization of collagen type I, the most abundant protein in ...bone and skin. In tetrapods collagen type I is a trimer mainly composed of two α1 chains and one α2 chain, encoded by COL1A1 and COL1A2 genes, respectively. In contrast, in zebrafish three type I collagen genes exist, col1a1a, col1a1b and col1a2 coding for α1(I), α3(I) and α2(I) chains. During embryonic and larval development the three collagen type I genes showed a similar spatio-temporal expression pattern, indicating their co-regulation and interdependence at these stages. In both embryonic and adult tissues, the presence of the three α(I) chains was demonstrated, although in embryos α1(I) was present in two distinct glycosylated states, suggesting a developmental-specific collagen composition. Even though in adult bone, skin and scales equal amounts of α1(I), α3(I) and α2(I) chains are present, the presented data suggest a tissue-specific stoichiometry and/or post-translational modification status for collagen type I. In conclusion, this data will be useful to properly interpret results and insights gained from zebrafish models of skeletal diseases.
The six-minute walk test (6MWT) distance could facilitate the assessment of cardiorespiratory fitness (CRF) in clinical practice as recommended. We aimed to develop a CRF classification using the ...6MWT distance in asymptomatic adults considering the treadmill maximum oxygen uptake (V˙O2max) as the gold standard method.
We evaluated V˙O2max and 6MWT distance in 1295 asymptomatic participants aged 18–80 years (60% women). Age- and sex-related CRF was classified based on the percentiles as very low (<5th percentile), low (5th–25th percentile), regular (26th–50th percentile), good (51st–75th percentile), excellent (76th–95th percentile), and superior (>95th percentile) for both V˙O2max and 6MWT distance. We investigated the 6MWT distance cut-off (%pred.) with the highest sensitivity and specificity for identifying each V˙O2max classification.
V˙O2max declined by 8.7% per decade in both men and women. The 6MWT distance declined by 9.3% per decade in women and 9.5% in men. We formulated age- and sex-related classification tables for CRF using the 6MWT distance. Moreover, the 6MWT distance (%pred.) showed excellent ability to identify very low CRF (6MWT distance ≤ 96%; AUC=0.819) and good ability to differentiate CRF as low (6MWT distance=97%–103%; AUC=0.735), excellent (6MWT distance=107%–109%; AUC=0.715), or superior (6MWT distance>109%; AUC=0.790). It was not possible to differentiate between participants with regular and good CRF.
The CRF classification by the 6MWT distance is valid in comparison with V˙O2max, especially for identifying adults with low CRF. It could be useful in clinical practice for screening and monitoring the cardiorespiratory risk in adults.
Abstract Objective: This study updates work published in 1998, which found that of 47 rating instruments appearing on websites offering health information, 14 described how they were developed, five ...provided instructions for use, and none reported the interobserver reliability and construct validity of the measurements. Design: All rating instrument sites noted in the original study were visited to ascertain whether they were still operating. New rating instruments were identified by duplicating and enhancing the comprehensive search of the internet and the medical and information science literature used in the previous study. Eligible instruments were evaluated as in the original study. Results: 98 instruments used to assess the quality of websites in the past five years were identified. Many of the rating instruments identified in the original study were no longer available. Of 51 newly identified rating instruments, only five provided some information by which they could be evaluated. As with the six sites identified in the original study that remained available, none of these five instruments seemed to have been validated. Conclusions: Many incompletely developed rating instruments continue to appear on websites providing health information, even when the organisations that gave rise to those instruments no longer exist. Many researchers, organisations, and website developers are exploring alternative ways of helping people to find and use high quality information available on the internet. Whether they are needed or sustainable and whether they make a difference remain to be shown. What is already known on this topic The rapid growth of healthcare websites in the 1990s was accompanied by initiatives to rate their quality, including award-like symbols on websites A systematic review of the reliability and validity of such rating instruments, published in 1998, showed that they were incompletely developed What this study adds Few of the rating instruments identified in 1998 remain functional; 51 new instruments were identified Of the 51 newly identified instruments, 11 were not functional, 35 were available but provided no information, and five provided information but were not validated Many researchers, organisations, and website developers are exploring alternative ways of helping people to find high quality information on the internet
The 6-minute walk test (6MWT) is a simple field test that is widely used in clinical settings to assess functional exercise capacity. However, studies with healthy subjects are scarce. We ...hypothesized that the 6MWT might be useful to assess exercise capacity in healthy subjects. The purpose of this study was to evaluate 6MWT intensity in middle-aged and older adults, as well as to develop a simple equation to predict oxygen uptake ( V ˙ O 2 ) from the 6-min walk distance (6MWD). Eighty-six participants, 40 men and 46 women, 40-74 years of age and with a mean body mass index of 28±6 kg/m2, performed the 6MWT according to American Thoracic Society guidelines. Physiological responses were evaluated during the 6MWT using a K4b2 Cosmed telemetry gas analyzer. On a different occasion, the subjects performed ramp protocol cardiopulmonary exercise testing (CPET) on a treadmill. Peak V ˙ O 2 in the 6MWT corresponded to 78±13% of the peak V ˙ O 2 during CPET, and the maximum heart rate corresponded to 80±23% of that obtained in CPET. Peak V ˙ O 2 in CPET was adequately predicted by the 6MWD by a linear regression equation: V ˙ O 2 mL·min-1·kg-1 = -2.863 + (0.0563×6MWDm) (R2=0.76). The 6MWT represents a moderate-to-high intensity activity in middle-aged and older adults and proved to be useful for predicting cardiorespiratory fitness in the present study. Our results suggest that the 6MWT may also be useful in asymptomatic individuals, and its use in walk-based conditioning programs should be encouraged.
Human activities are affecting habitats and wildlife populations worldwide. Tropical forests are one of the most affected environments, mainly due to deforestation and poaching. Since high levels of ...anthropogenic pressure on forest ecosystems, including illegal logging and hunting, occur in southwest Myanmar (Rakhine State), we analyzed the effects of human disturbance on medium to large mammals in this region. We used camera‐trapping data collected over three consecutive years to investigate occurrence probabilities of 10 species: five common species exploited for bushmeat consumption, and five threatened species targeted by the illegal wildlife trade. We used a hierarchical single‐species multi‐season occupancy model implemented in a Bayesian framework to evaluate the effects of human disturbances and persistent habitat characteristics, such as the proportion of remaining pristine evergreen forest and the elevation, on occurrence probabilities. We found that occupancy probabilities of three out of five target species for the illegal wildlife trade were positively linked to forest habitats, whereas among common species hunted for bushmeat consumption the Northern red muntjak and the Malayan porcupine were negatively affected by human presence. The effects of human and habitat covariates were varied for other species of both groups. We confirmed results from previous studies that human disturbance is a driver of occurrence probabilities for some species in tropical areas. Our findings suggest that as protection of rainforest habitat is fundamental to the conservation of tropical ecosystems, law enforcement, patrolling, and local engagement activities are also recommended to mitigate forest and species exploitation. Finally, camera trapping could be a first step to identify areas where human presence affects species occupancy and help local authorities to develop more fine‐tuned conservation plans.
We used camera trapping data in Rakhine (Myanmar) to investigate human impact on 10 selected species targeted by hunting. We found that threatened species targeted by illegal wildlife trade are positively affected by evergreen forest habitats, while species hunted for bushmeat consumption are negatively affected by human presence associated with different activities in the forests. These data provide useful information for the development of specific conservation actions in our study area.
Spirometry has been used as the main strategy for assessing ventilatory changes related to occupational exposure to particulate matter (OEPM). However, in some cases, as one of its limitations, it ...may not be sensitive enough to show abnormalities before extensive damage, as seen in restrictive lung diseases. Therefore, we hypothesized that cardiopulmonary exercise testing (CPET) may be better than spirometry to detect early ventilatory impairment caused by OEPM. We selected 135 male workers with at least one year of exposure. After collection of self-reported socioeconomic status, educational level, and cardiovascular risk data, participants underwent spirometry, CPET, body composition assessment (bioelectrical impedance), and triaxial accelerometry (for level of physical activity in daily life). CPET was performed using a ramp protocol on a treadmill. Metabolic, cardiovascular, ventilatory, and submaximal relationships were measured. We compared 52 exposed to 83 non-exposed workers. Multiple linear regressions were developed using spirometry and CPET variables as outcomes and OEPM as the main predictor, and adjusted by the main covariates. Our results showed that OEPM was associated with significant reductions in peak minute ventilation, peak tidal volume, and breathing reserve index. Exposed participants presented shallower slope of ΔVT/ΔlnV̇E (breathing pattern), i.e., increased tachypneic breathing pattern. The OEPM explained 7.4% of the ΔVT/ΔlnV̇E variability. We found no significant influence of spirometric indices after multiple linear regressions. We conclude that CPET might be a more sensitive feature of assessing early pulmonary impairment related to OEPM. Our cross-sectional results suggested that CPET is a promising tool for the screening of asymptomatic male workers.
Background
MRgFUS Vim ablation is increasingly used for the treatment of tremor in ET e PD patients but there is little published research on the importance of operator experience in this procedure. ...This study aims to evaluate the learning curve and the influence of the operator experience on the procedural and clinical outcomes.
Methods
We retrospectively evaluated 90 patients (38 ET, 52 PD) submitted to MRgFUS unilateral thalamotomy in the period between February 2018 and July 2020. Clinical endpoints, procedural times, and technical parameters were recorded in all procedures. Based on the time of treatment, patients were divided into three groups of 30 units each, comparing all variables between each time period group.
Results
In Group A, the average patient preparation time was 120.6 min, the treatment time was 105.2 min, the number of was sonications 14.1, and the mean target shifts 3.1. In Group B, the mean preparation time was 105.5 min, the treatment time was 89.5 min, the number of sonications was 13.2, and the target shifts 3.0. Group C showed inferior values of preparation time (101.9 min), treatment time (71.7 min), numbers of sonications (10.6), and shifts (1.7). Thalamotomy-related complications occurred in 9 patients of Group A, 2 of Group B, and 5 of Group C. Tremor relapse occurred in 7 patients of Group A, 3 of Group B, and 2 of Group C. The days of hospitalization were comparable in the three groups.
Conclusions
The operators experience is associated with the improvement of clinical and procedural outcome in MRgFUS thalatomy for the treatment of ET and PD tremor.
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