The structural dimension of metal-organic frameworks (MOFs) is of great importance in defining their properties and thus applications. In particular, 2D layered MOFs are of considerable interest ...because of their useful applications, which are facilitated by unique structural features of 2D materials, such as a large number of open active sites and high surface areas. Herein, this work demonstrates a methodology for the selective synthesis of a 2D layered MOF in the presence of the competitive formation of a 3D MOF. The ratio of the reactants, metal ions and organic building blocks used during the reaction is found to be critical for the selective formation of a 2D MOF, and is associated with its chemical composition. In addition, the well defined and uniform micro-sized 2D MOF particles are successfully synthesized in the presence of an ultrasonic dispersion. Moreover, the laminated 2D MOF layers are directly synthesized via a modified bottom-up lamination method, a combination of chemical and physical stimuli, in the presence of surfactant and ultrasonication.
Highlights • A maternal group B streptococcal (GBS) vaccine is currently in trials. • Maternal GBS vaccination would reduce the GBS disease burden in South Africa and be very cost-effective by WHO ...guidelines. • Risk factor-based intrapartum antibiotic prophylaxis (RFB-IAP) is also very cost-effective but has limited health impact. • Vaccination plus RFB-IAP would be more effective and more costly than vaccination alone, but still very cost-effective. • Vaccine will be an especially useful public health tool in settings where RFB-IAP is not feasible.
Abstract Purpose To reanalyze results reported in 2008, using propensity score matching, to test the treatment effect of non-leisure physical activity on survival. Methods McCullagh's ordinal logit ...model was used to estimate propensity scores, separately for adults aged 35–59 and 60–74 years at baseline in the National Health and Nutrition Examination Survey I Epidemiologic Followup Study, for three levels of non-leisure activity. Each untreated adult (low non-leisure activity) was matched to two treated adults from the same age group, one with moderate and one with high non-leisure activity. Multivariable Cox proportional hazard regressions were fitted to the matched samples and compared with regressions fitted to unmatched samples. Results Except for moderate leisure-time activity and age, observed covariates were well balanced after matching. For adults aged 35–59 years, matched regressions showed smaller mortality reductions: 23% for moderate and 32% for high non-leisure activity, compared with low non-leisure activity. For adults aged 60–74 years, matched regressions showed a smaller mortality reduction for moderate non-leisure activity (29%) but a larger reduction for high non-leisure activity (47%). Conclusions In line with published reviews of conventional multivariable analysis versus propensity score matching, Cox regressions on matched and unmatched samples produced similar estimates of treatment effects for non-leisure activity, but the estimates from matched regressions were usually smaller.
Porous metal–organic frameworks (MOFs) are interesting materials owing to their interesting structural features and their many useful properties and applications. In particular, the structural ...features are greatly important to optimize the MOFs’ porosities and so properties. Indeed, the MOFs’ well-developed micropore and high surface area are the most important structural features, and as such, many practical applications of MOFs originate from these structural features. We herein demonstrate a strategy for improving the crystallinity of MOFs, and so increasing the porosity and surface area of poorly crystalline MOFs by making them in core–shell-type hybrids through the induced growth on the well-crystalline template. Although poorly crystalline versions of MOFs generate naturally in the absence of the well-crystalline template, well-crystalline versions of MOFs produce inductively in the presence of the well-crystalline template. In addition, the crystallinity enhancement of MOFs brings together the improvement in their porosities and surface areas. The surface areas and pore volumes of the well-crystalline versions of MOFs produced through the induced growth on the template are calculated based on this study, indicating that MOF surface areas increase by up to 7 times compared to the poorly crystalline versions.
Translational control plays a key role in regulation of neuronal activity and behavior. Deletion of the translational repressor 4E-BP2 in mice alters excitatory and inhibitory synaptic functions, ...engendering autistic-like behaviors. The contribution of 4E-BP2-dependent translational control in excitatory and inhibitory neurons and astrocytic cells to these behaviors remains unknown. To investigate this, we generated cell-type-specific conditional 4E-BP2 knockout mice and tested them for the salient features of autism, including repetitive stereotyped behaviors (self-grooming and marble burying), sociability (3-chamber social and direct social interaction tests), and communication (ultrasonic vocalizations in pups). We found that deletion of 4E-BP2 in GABAergic inhibitory neurons, defined by Gad2, resulted in impairments in social interaction and vocal communication. In contrast, deletion of 4E-BP2 in forebrain glutamatergic excitatory neurons, defined by Camk2a, or in astrocytes, defined by Gfap, failed to cause autistic-like behavioral abnormalities. Taken together, we provide evidence for an inhibitory-cell-specific role of 4E-BP2 in engendering autism-related behaviors.
Effective and timely responses to unexpected contingencies are crucial for enhancing the resilience of power grids. Given the fast, complex process of cascading propagation, corrective actions such ...as optimal load shedding (OLS) are difficult to attain in large-scale networks due to the computation complexity and communication latency issues. This work puts forth an innovative learning-for-OLS approach by constructing the optimal decision rules of load shedding under a variety of potential contingency scenarios through offline neural network (NN) training. Notably, the proposed NN-based OLS decisions are fully decentralized, enabling individual load centers to quickly react to the specific contingency using readily available local measurements. Numerical studies on the IEEE 14-bus system have demonstrated the effectiveness of our scalable OLS design for real-time responses to severe grid emergency events.
Survival analysis is an advanced statistical method to investigate the occurrence and the timing of an important event such as school access, dropout, and graduation in a longitudinal framework. The ...aim of our study is to provide practical guidelines for empirical researchers in choosing an appropriate survival analysis model. For this goal, this study chose two major survival analytical models of a discrete-time hazard model and a Cox regression model and compared analytical outcomes considering time metrics, as well as sample sizes and censoring proportions. In the analytical model, the combined specifications of varying factors using two models were adopted to analyse the Educational Longitudinal Study of 2002. We chose the college access of Hispanic English Language Learners to understand the importance of adopting a proper survival model to examine the educational outcome in the educational context. Importantly, we considered the hazard probability for the target event in the model specification which is a fundamental yet often neglected component of survival analysis. We recommended discrete models for the cases with a smaller number of time points, larger time metrics, larger sample size, and smaller proportions of censored observations.
Students with emotional and behavioral disorders (EBD) characteristically experience academic difficulties. There is growing evidence that the continuum from academic competence to underachievement ...is partially explained by executive function (EF; neurocognitive attention-regulation processes) and stress. Yet, there is scarce research investigating these relationships among students with or at risk for EBD, especially during the elevated stress and risk period of middle school, and particularly among racially/ethnically under-represented groups. Therefore, with 118 U.S. middle schoolers with or at risk for EBD and typical peers (70% Hispanic/Latinx; 25% Black), we examined group differences and relationships among perceived family, peer, and school stress, EF, and academic outcomes. When compared with their typical peers, students with or at risk for EBD scored lower on EF and academic tasks. For all students, higher EF predicted better academic functioning. Perceived stress was directly and negatively related with EF and indirectly associated with academic outcomes via EF.
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