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Abstract: Wavefront shaping, which is often achieved using liquid crystal (LC) spatial light modulators, is particularly important for a wide range of applications including laser microfabrication and micromanipulation, microscopy, and quantum optics. In this work, results are presented for the first integrated LC phase modulator that combines a flexoelectro‐optic LC layer (that behaves as a switchable λ/2 waveplate) with a polymerized reactive mesogen layer (which acts as a λ/4 waveplate) and a mirrored substrate that creates a double‐pass geometry. For a flexoelectro‐optic LC layer that exhibits switching angles of ±45° at a voltage of ±85 V a full 2π phase modulation is observed when driven by a 1 kHz waveform. Experimental results are also compared with modeling using Jones calculus of the amplitude and phase variation when the LC and the polymer layer deviate from their desired waveplate conditions. The development and demonstration of an integrated device is particularly significant for applications where size and cost are critical factors such as in LiDAR for the Space and Automotive industries, respectively.

Electrocaloric (EC) materials show promise in eco-friendly solid-state refrigeration and integrable on-chip thermal management. While direct measurement of EC thin-films still remains challenging, a generic theoretical framework for quantifying the cooling properties of rich EC materials including normal-, relaxor-, organic- and anti-ferroelectrics is imperative for exploiting new flexible and room-temperature cooling alternatives. Here, we present a versatile theory that combines Master equation with Maxwell relations and analytically relates the macroscopic cooling responses in EC materials with the intrinsic diffuseness of phase transitions and correlation characteristics. Under increased electric fields, both EC entropy and adiabatic temperature changes increase quadratically initially, followed by further linear growth and eventual gradual saturation. The upper bound of entropy change (∆Smax) is limited by distinct correlation volumes (V cr ) and transition diffuseness. The linearity between V cr and the transition diffuseness is emphasized, while ∆Smax = 300 kJ/(K.m3) is obtained for Pb0.8Ba0.2ZrO3. The ∆Smax in antiferroelectric Pb0.95Zr0.05TiO3, Pb0.8Ba0.2ZrO3 and polymeric ferroelectrics scales proportionally with V cr-2.2, owing to the one-dimensional structural constraint on lattice-scale depolarization dynamics; whereas ∆Smax in relaxor and normal ferroelectrics scales as ∆Smax ~ V cr-0.37, which tallies with a dipolar interaction exponent of 2/3 in EC materials and the well-proven fractional dimensionality of 2.5 for ferroelectric domain walls.

In the last 2 years, rubber tree abnormal leaf fall occurred over large area in Xishuangbanna rubber plantation, and the symptoms were similar to those of rubber tree Phytophthora leaf fall disease. In order to clarify the pathogenic species and screen fungicides for effective control of this disease, the pathogen was isolated and purified by tissue isolation and mycelia cusp purification method, and the pathogenicity was determined by Koch' s postulates test, morphological and physiological characteristics, rDNA-ITS and COX II gene sequence analysis. The results showed that the pathogen caused rubber tree abnormal leaf fall was identified as Phytophthora botryosa, which was a new record pathogen of rubber tree Phytophthora leaf fall disease in China. The antibiotic activities of 15 fungicides was tested in vitro with mycelial growth rate method. 48% dimethomorph-cyazofamid SC (suspension concentrate), 80% dimethomorph WG (water dispersible granule), 30% metalaxyl-dimethomorph WG, 35% dimethomorph-cymoxanil SC, 30% floridomide-metalaxyl WG and 0.3% tetramycin AS (aqueoces solution) could effectively inhibit the mycelial growth of the pathogen, with EC50 of 0.137 1, 0.175 9, 0.201 7, 0.2577, 0.265 1, 0.351 0 mg⋅L-1, respectively, which could be used as candidates for control of the disease in the field. [ABSTRACT FROM AUTHOR]

3D architecratured transition metal dichalcogenides constructed by atomically thin layers are appealing building blocks in various applications, such as catalysts, energy storage, conversions, sensors, and so on. However, the direct growth of 3D transition metal dichalcogenides architectures with high crystal quality and well‐controlled size/thickness remains a huge challenge. Herein, we report a facile, highly‐repeatable, and versatile chemical vapor deposition strategy, for the mass production of high‐quality 3D‐architecratured transition metal dichalcogenides (e.g., MoS2, WS2, and ReS2) and their alloys (e.g., WxMo(1–x)S2 and RexMo(1–x)S2) nanosheets on naturally abundant and low‐cost diatomite templates. Particularly, the purified transition metal dichalcogenides products exhibit unique and designable 3D biomorphic hierarchical microstructures, controllable layer thicknesses, tailorable chemical compositions, and good crystallinities. The weak interlayer interactions endow them with good dispersity in solutions to form stable additive‐free inks for solution‐processing‐based applications, for example, high‐permeable and high‐stable separation membranes for water purification, and efficient electrocatalysts for hydrogen evolution reactions. This work paves ways for the low‐cost, mass production of versatile transition metal dichalcogenides powder‐like materials with designable structures and properties, toward energy/environmental‐related applications and beyond. [ABSTRACT FROM AUTHOR]

Background and Purpose: Muscle protein catabolism in patients with diabetic nephropathy (DN) results in striking loss of muscle proteins, which increases morbidity and mortality risks. Evidence shows that short‐chain fatty acids (SCFAs) play an important role in health maintenance and disease development. Recently, the connection between butyrate (a SCFA) and DN has been revealed, although the relationship between butyrate and muscle atrophy remains unclear. Experimental Approach We studied changes in serum butyrate levels in DN patients using metabolomic analyses. In db/db mice, protective effects of butyrate on DN‐induced muscle atrophy. were explored. Inhibition of muscle atrophy by butyrate and the underlying mechanism(s) were studied in C2C12 cells exposed to high glucose/lipopolysaccharide (HG/LPS). Key Results: Butyrate levels in DN patients were significantly decreased. In db/db mice, supplementing normal diet with butyrate improved intestinal barrier function. Concurrently, butyrate alleviated muscle atrophy, promoted PI3K/Akt/mTOR signalling, and suppressed oxidative stress and autophagy in skeletal muscle of db/db mice, and in HG/LPS‐exposed C2C12 cells. Further, FFA2 receptors, key components of SCFA signalling, were decreased in skeletal muscle of db/db mice and in HG/LPS‐exposed C2C12 cells. Overexpression of FFA2 receptors activated PI3K/Akt/mTOR signalling and inhibited oxidative stress and autophagy in HG/LPS‐exposed C2C12 cells. Silencing of FFA2 blocked PI3K/Akt/mTOR signalling that was improved by butyrate, as well as the suppression of oxidative stress and reduction of autophagy. Conclusion and Implication: Butyrate exerts protective effects on muscle atrophy induced by DN by enhancing intestinal barrier function and activating the FFA2 receptor‐mediated PI3K/Akt/mTOR pathway. [ABSTRACT FROM AUTHOR]