Advanced piezoresistance of extended metal/insulator core shell nanoparticle assemblies

Assembled metal/insulator nanoparticles with a core/shell geometry provide access to materials containing a large number (>106) of tunneling barriers. We demonstrate the production of ceramic coated metal nanoparticles exhibiting an exceptional pressure sensitive conductivity. We further show that graphene bi- and trilayers on 20 nm copper nanoparticles are insulating in such core/shell geometry and show a similar pressure dependent conductivity. This demonstrates that core/shell metal/insulator assemblies offer a route to alternative sensing materials.Comment: 14 pages, 3 figures, published in Physical Review Letter

Biodegradable All-Polymer Field-Effect Transistors Printed on Mater-Bi

The growing demand of disposable electronics raises serious concerns for the corresponding increase in the amount of electronic waste, with severe environmental impact. Organic and flexible electronics have been proposed long ago as a more sustainable and energy-efficient technological platform with respect to established ones. Yet, such technology is leading to a drastic increase of plastic waste if common approaches for flexible substrates are followed. In this scenario, biodegradable solutions can significantly limit the environmental impact, actively contributing to eliminate the waste streams (plastic or electronic) associated with disposal of devices. However, achieving suitably scalable processes to pattern mechanically robust organic electronics onto largely available biodegradable substrates is still an open challenge. In this work, all-organic and highly flexible field-effect transistors, inkjet printed onto the biodegradable and compostable commercial substrate Mater-Bi, are demonstrated. Because of the thermal instability of Mater-Bi, no annealing steps are applied, producing devices with limited carrier mobility, yet showing correct n-type behavior and robustness to bending and crumpling. The degradation behavior of the final system shows unaltered biodegradability level according to ISO 14851. These results represent a promising step toward sustainable flexible and large-area electronics, combining energy and materials efficient processes with largely available biodegradable substrates

Top Management Team Diversity: A systematic Review

Empirical research investigating the impact of top management team (TMT) diversity on executives’ decision making has produced inconclusive results. To synthesize and aggregate the results on the diversity-performance link, a meta-regression analysis (MRA) is conducted. It integrates more than 200 estimates from 53 empirical studies investigating TMT diversity and its impact on the quality of executives’ decision making as reflected in corporate performance. The analysis contributes to the literature by theoretically discussing and empirically examining the effects of TMT diversity on corporate performance. Our results do not show a link between TMT diversity and performance but provide evidence for publication bias. Thus, the findings raise doubts on the impact of TMT diversity on performance

Economic liberalization and the antecedents of top management teams: evidence from Turkish 'big' business

There has been an increased interest in the last two decades in top management teams (TMTs) of business firms. Much of the research, however, has been US-based and concerned primarily with TMT effects on organizational outcomes. The present study aims to expand this literature by examining the antecedents of top team composition in the context of macro-level economic change in a late-industrializing country. The post-1980 trade and market reforms in Turkey provided the empirical setting. Drawing upon the literatures on TMT and chief executive characteristics together with punctuated equilibrium models of change and institutional theory, the article develops the argument that which firm-level factors affect which attributes of TMT formations varies across the early and late stages of economic liberalization. Results of the empirical investigation of 71 of the largest industrial firms in Turkey broadly supported the hypotheses derived from this premise. In the early stages of economic liberalization the average age and average organizational tenure of TMTs were related to the export orientation of firms, whereas in later stages, firm performance became a major predictor of these team attributes. Educational background characteristics of teams appeared to be under stronger institutional pressures, altering in different ways in the face of macro-level change

Differences that matter: hiring modes and demographic (dis)similarity in executive selection

Scholars, practitioners, and policymakers have long acknowledged the importance of understanding the antecedents of top management team (TMT) composition. Yet, research on how and why firms select executives who are demographically dissimilar to incumbent TMT members remains limited. We take a step toward answering these questions by employing a sample of 575 individual-level executive appointments at 170 large European firms between 2005 and 2009. Drawing on the person-group fit perspective, we argue that firms are more likely to appoint socio-demographically dissimilar executives through internal promotion – while external hires are more likely to socio-demographically resemble incumbent top managers. Our results support the hypothesized relationship. They also show that this relationship is influenced by the level of administrative complexity and environmental uncertainty facing the firm. Overall, our theory and results enhance our understanding of ‘why top management teams are composed the way they are’, by highlighting the impact of internal and external hiring modes in the selection of demographically (dis)similar executives

The Political De-Determination of Legal Rules and the Contested Meaning of the ‘No Bailout’ Clause

Traditional debates on legal theory have devoted a great deal of attention to the question of the determinacy of legal rules. With the aid of social sciences and linguistics, this article suggests a way out of the ‘determinate-indeterminate’ dichotomy that has dominated the academic debate on the topic so far. Instead, a dynamic approach is proposed, in which rules are deemed to undergo processes of political ‘de-determination’ and ‘re-determination’. To illustrate this, the article uses the example of Art. 125 of the Treaty on the Functioning of the European Union, the ‘no bailout’ provision, which played a major role in the management of the Euro-crisis. As will be shown, with the start of the crisis, this provision, whose meaning was once scarcely controversial, became the object of intense interpretative disagreement. As it became politically relevant, the rule also became the site of interpretative competitions, until the intervention of the European Court of Justice disambiguated and redefined its meaning

First-line treatment for advanced ovarian cancer: paclitaxel, platinum and the evidence

Four large randomised trials of paclitaxel in combination with platinum against a platinum-based control treatment have now been published in full, representing around 88% (3588 out of 4057) of patients randomised into the eight known trials of this question. There is substantial heterogeneity in the results of these four trials. Four main explanations for this heterogeneity have been proposed: differences in the extent and timing of ‘crossover’ to taxanes in the control groups; differences in the types of patient included; differences in the effectiveness of the research regimens used; differences in the effectiveness of the control regimens used. In this study we examine whether any of these explanations is consistent with the pattern of results seen in these trials. Each explanation suggests that a particular characteristic of each trial was responsible for the results observed. For each explanation the trials were split into groups according to that characteristic, in order to partition the total heterogeneity into that seen ‘within’ and ‘between’ groups of trials. If a particular explanation was consistent with the pattern of results, we would expect to see relatively little heterogeneity within each group of trial results viewed in this way, with most of the heterogeneity being between groups which are dissimilar with respect to the key characteristic. Heterogeneity ‘within’ and ‘between’ groups was formally compared using the F-ratio. If any explanation appeared to be consistent with the results of the trials, it was considered whether the explanation was also consistent with other evidence available about these regimens. Only one explanation appeared to be consistent with the pattern of results seen in these trials, and that was differences in effectiveness of the control arms used in these trials. This suggests that the very positive results in favour of paclitaxel/cisplatin seen in two of the trials may have been due to the use of a suboptimal control arm. There is no direct evidence about the relative effectiveness of the control arms used in these trials, but indirect evidence is consistent with the conclusion that the cyclophosphamide/cisplatin regimen used in two of the trials may be less effective than the control regimens used in the other trials. Specific concerns about the choice of a cyclophosphamide/cisplatin control arm in the first of these trials to report were raised before the results of the other trials were known, i.e. before any heterogeneity had been observed. Further investigation of this question would be useful. In the meantime, given all of the randomised evidence on the efficacy and toxicity associated with the regimens used in these trials, we conclude that single agent carboplatin is a safe and effective first-line treatment for women with advanced ovarian cancer

Radiotherapy and temozolomide for newly diagnosed glioblastoma and anaplastic astrocytoma: validation of Radiation Therapy Oncology Group-Recursive Partitioning Analysis in the IMRT and temozolomide era

Since the development of the Radiation Therapy Oncology Group-Recursive Partitioning Analysis (RTOG-RPA) risk classes for high-grade glioma, radiation therapy in combination with temozolomide (TMZ) has become standard care. While this combination has improved survival, the prognosis remains poor in the majority of patients. Therefore, strong interest in high-grade gliomas from basic research to clinical trials persists. We sought to evaluate whether the current RTOG-RPA retains prognostic significance in the TMZ era or alternatively, if modifications better prognosticate the optimal selection of patients with similar baseline prognosis for future clinical protocols. The records of 159 patients with newly-diagnosed glioblastoma (GBM, WHO grade IV) or anaplastic astrocytoma (AA, WHO grade III) were reviewed. Patients were treated with intensity-modulated radiation therapy (IMRT) and concurrent followed by adjuvant TMZ (n = 154) or adjuvant TMZ only (n = 5). The primary endpoint was overall survival. Three separate analyses were performed: (1) application of RTOG-RPA to the study cohort and calculation of subsequent survival curves, (2) fit a new tree model with the same predictors in RTOG-RPA, and (3) fit a new tree model with an expanded predictor set. All analyses used a regression tree analysis with a survival outcome fit to formulate new risk classes. Overall median survival was 14.9 months. Using the RTOG-RPA, the six classes retained their relative prognostic significance and overall ordering, with the corresponding survival distributions significantly different from each other (P < 0.01, χ2 statistic = 70). New recursive partitioning limited to the predictors in RTOG-RPA defined four risk groups based on Karnofsky Performance Status (KPS), histology, age, length of neurologic symptoms, and mental status. Analysis across the expanded predictors defined six risk classes, including the same five variables plus tumor location, tobacco use, and hospitalization during radiation therapy. Patients with excellent functional status, AA, and frontal lobe tumors had the best prognosis. For patients with newly-diagnosed high-grade gliomas, RTOG-RPA classes retained prognostic significance in patients treated with TMZ and IMRT. In contrast to RTOG-RPA, in our modified RPA model, KPS rather than age represented the initial split. New recursive partitioning identified potential modifications to RTOG-RPA that should be further explored with a larger data set

Composition of the Top Management Team and Firm International Diversification

This study investigates the impact of various top management team characteristics on firm international diversification. Relying on data from 126 firms in the electronics industry, we find that certain top management team characteristics are related to international expansion. Specifically, results indicate that lower average age, higher average tenure, higher average elite education, higher average international experience, and higher tenure heterogeneity are associated with firm international diversification. The study reinforces the importance of top management team composition in internationalization decisions and suggests further research in this context.Yeshttps://us.sagepub.com/en-us/nam/manuscript-submission-guideline

Wettability Switching Techniques on Superhydrophobic Surfaces

The wetting properties of superhydrophobic surfaces have generated worldwide research interest. A water drop on these surfaces forms a nearly perfect spherical pearl. Superhydrophobic materials hold considerable promise for potential applications ranging from self cleaning surfaces, completely water impermeable textiles to low cost energy displacement of liquids in lab-on-chip devices. However, the dynamic modification of the liquid droplets behavior and in particular of their wetting properties on these surfaces is still a challenging issue. In this review, after a brief overview on superhydrophobic states definition, the techniques leading to the modification of wettability behavior on superhydrophobic surfaces under specific conditions: optical, magnetic, mechanical, chemical, thermal are discussed. Finally, a focus on electrowetting is made from historical phenomenon pointed out some decades ago on classical planar hydrophobic surfaces to recent breakthrough obtained on superhydrophobic surfaces