Phonon-polaritonics: enabling powerful capabilities for infrared photonics

Here, we review the progress and most recent advances in phonon-polaritonics, an emerging and growing field that has brought about a range of powerful possibilities for mid- to far-infrared (IR) light. These extraordinary capabilities are enabled by the resonant coupling between the impinging light and the vibrations of the material lattice, known as phonon-polaritons (PhPs). These PhPs yield a characteristic optical response in certain materials, occurring within an IR spectral window known as the reststrahlen band. In particular, these materials transition in the reststrahlen band from a high-refractive-index behavior, to a near-perfect metal behavior, to a plasmonic behavior – typical of metals at optical frequencies. When anisotropic they may also possess unconventional photonic constitutive properties thought of as possible only with metamaterials. The recent surge in two-dimensional (2D) material research has also enabled PhP responses with atomically-thin materials. Such vast and extraordinary photonic responses can be utilized for a plethora of unusual effects for IR light. Examples include sub-diffraction surface wave guiding, artificial magnetism, exotic photonic dispersions, thermal emission enhancement, perfect absorption and enhanced near-field heat transfer. Finally, we discuss the tremendous potential impact of these IR functionalities for the advancement of IR sources and sensors, as well as for thermal management and THz-diagnostic imaging

The Expanding Role of Dapagliflozin Beyond the Glucose-lowering Effect

Sodium-glucose cotransporter 2 (SGLT2) inhibitors have varied metabolic effects beyond increasing glycosuria. This consensus review examines the role of dapagliflozin in health promotion, particularly its benefits in patients with and without type 2 diabetes mellitus (T2DM) and in cardiorenal rehabilitation post-coronavirus disease 2019 (COVID-19). Consensus recommendations were developed by subject experts in Endocrinology and Diabetology based on the online meeting held on 27 June 2020 to review the available evidence related to the role of SGLT2 inhibitors, with a focus on cardiovascular and renal metabolic therapy. Evidence suggests that dapagliflozin has a direct role in improving clinical outcomes in patients with chronic kidney disease (CKD) or heart failure (HF). These benefits of dapagliflozin were independent of reduction in blood pressure, glycemic control and weight, and also extend to patients without diabetes. The use of dapagliflozin in metabolic syndrome was endorsed by the majority of the experts; however, this would be off-label.It was opined that the role of dapagliflozin would currently be limited to treating T2DM with a focus on preventing HF or kidney disease progression. The need for conducting multidisciplinary academic meetings to have a balanced approach regarding the use of dapagliflozin among nondiabetic patients and the need for detailed evaluation of the role of SGLT2 inhibitors in vasculometabolic and cardiorenal rehabilitation post-COVID was also suggested

The Expanding Role of Dapagliflozin Beyond the Glucose-lowering Effec

Sodium-glucose cotransporter 2 (SGLT2) inhibitors have varied metabolic effects beyond increasing glycosuria. This consensus review examines the role of dapagliflozin in health promotion, particularly its benefits in patients with and without type 2 diabetes mellitus (T2DM) and in cardiorenal rehabilitation post-coronavirus disease 2019 (COVID-19). Consensus recommendations were developed by subject experts in Endocrinology and Diabetology based on the online meeting held on 27 June 2020 to review the available evidence related to the role of SGLT2 inhibitors, with a focus on cardiovascular and renal metabolic therapy. Evidence suggests that dapagliflozin has a direct role in improving clinical outcomes in patients with chronic kidney disease (CKD) or heart failure (HF). These benefits of dapagliflozin were independent of reduction in blood pressure, glycemic control and weight, and also extend to patients without diabetes. The use of dapagliflozin in metabolic syndrome was endorsed by the majority of the experts; however, this would be off-label. It was opined that the role of dapagliflozin would currently be limited to treating T2DM with a focus on preventing HF or kidney disease progression. The need for conducting multidisciplinary academic meetings to have a balanced approach regarding the use of dapagliflozin among nondiabetic patients and the need for detailed evaluation of the role of SGLT2 inhibitors in vasculometabolic and cardiorenal rehabilitation post-COVID was also suggested

Ultrathin compound semiconductor on insulator layers for high performance nanoscale transistors

Over the past several years, the inherent scaling limitations of electron devices have fueled the exploration of high carrier mobility semiconductors as a Si replacement to further enhance the device performance. In particular, compound semiconductors heterogeneously integrated on Si substrates have been actively studied, combining the high mobility of III-V semiconductors and the well-established, low cost processing of Si technology. This integration, however, presents significant challenges. Conventionally, heteroepitaxial growth of complex multilayers on Si has been explored. Besides complexity, high defect densities and junction leakage currents present limitations in the approach. Motivated by this challenge, here we utilize an epitaxial transfer method for the integration of ultrathin layers of single-crystalline InAs on Si/SiO2 substrates. As a parallel to silicon-on-insulator (SOI) technology14,we use the abbreviation "XOI" to represent our compound semiconductor-on-insulator platform. Through experiments and simulation, the electrical properties of InAs XOI transistors are explored, elucidating the critical role of quantum confinement in the transport properties of ultrathin XOI layers. Importantly, a high quality InAs/dielectric interface is obtained by the use of a novel thermally grown interfacial InAsOx layer (~1 nm thick). The fabricated FETs exhibit an impressive peak transconductance of ~1.6 mS/{\mu}m at VDS=0.5V with ON/OFF current ratio of greater than 10,000 and a subthreshold swing of 107-150 mV/decade for a channel length of ~0.5 {\mu}m

Moraxella catarrhalis acquisition, airway inflammation and protease-antiprotease balance in chronic obstructive pulmonary disease

<p>Abstract</p> <p>Background</p> <p><it>Moraxella catarrhalis </it>causes approximately 10% of exacerbations in chronic obstructive pulmonary disease (COPD) and also colonizes the lower airway in stable patients. Little is known about the effects of colonization by <it>M. catarrhalis </it>on airway inflammation and protease-antiprotease balance, and how these changes compare to those seen during exacerbations. Since COPD is a progressive inflammatory disease, elucidating the effects of bacterial colonization and exacerbation on airway inflammation is relevant to understanding disease progression in COPD. Our aims were (1) Analyze changes in airway inflammation in colonization and exacerbation of COPD due to <it>M. catarrhalis</it>; (2) Explore protease-antiprotease balance in colonization and exacerbation due to <it>M. catarrhalis</it>. Our hypothesis were (1) Acquisition of a new strain of M. catarrhalis in COPD increases airway inflammation from baseline and alters the protease-antiprotease balance towards a more proteolytic environment; (2) These changes are greater during exacerbations associated with <it>M. catarrhalis </it>as compared to colonization.</p> <p>Methods</p> <p>Thirty-nine consecutive COPD patients with 76 acquisitions of a new strain of <it>M. catarrhalis </it>over a 6-year period were identified in a prospective study. Seventy-six pre-acquisition sputum supernatant samples, obtained just before acquisition of <it>M catarrhalis</it>, and 76 acquisition samples (34 were associated with exacerbation, 42 with colonization) were analyzed for IL-8, TNF-α, Neutrophil Elastase (NE) and Secretory leukocyte protease inhibitor (SLPI). Changes were compared in paired samples from each patient.</p> <p>Results</p> <p>IL-8, TNF-α and NE were significantly elevated after acquisition of <it>M. catarrhalis</it>, compared to pre-acquisition samples (p =< 0.001 for all three). These changes were present in colonization (p = 0.015 for IL-8; p =< 0.001 for TNF-α and NE) as well as in exacerbation (p =< 0.001 for all three), compared to pre-acquisition levels. SLPI was significantly lower after acquisition (p =< 0.001), in colonization (p =< 0.001) as well as in exacerbation (p = 0.004), compared to pre-acquisition levels. SLPI levels correlated negatively with NE levels (R²= 0.07; p = 0.001).</p> <p>Conclusion</p> <p>Acquisition of <it>M. catarrhalis </it>in COPD causes increased airway inflammation and worsening protease-antiprotease imbalance during exacerbations and also in colonization, even in the absence of increased symptoms. These effects could contribute to progression of airway disease in COPD.</p

Control of molecular topology and metal nuclearity in multimetallic assemblies: designer metallosiloxanes derived from silanetriols

Lipophilic N-bonded silanetriol RSi(OH)3 (R=(2,6-iPr2C6H3)N(SiMe3)) can be utilized as an effective synthon for building a variety of multimetallic assemblies containing the Si-O-M motif. The type of metallosiloxane synthesized-its nuclearity and its molecular topology-can be readily modulated by the choice of the metal substrate, reaction stoichiometry, and reaction conditions. It is anticipated that the synthetic principles elaborated here will allow the design of many other multifunctional synthons