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This investigation reveals a practical method for improving thermal stability and reducing the specific contact resistivity ( $\rho _{\text {c}}$ ) of titanium-based Ohmic contact. Inserting an ultrathin molybdenum (Mo) layer, with thicknesses ranging from 3 to 10Å, between titanium (Ti) and heavily doped silicon (Si) substrates effectively impedes the further diffusion of Si into the metal layer. Mo silicide contributes to lowering the temperature required for the formation of the C54-phase Ti silicide by 50 °C to 100 °C and facilitates the emergence of the low-resistance phase C54-TiSi2. Experimental evidence indicates that the insertion of thinner Mo layers significantly reduces $\rho _{\text {c}}$ , which remains around the order of $10^{-{8}}~\Omega \cdot $ cm2 after extensive annealing at 750 °C for 30 minutes.

We proposed a high-sensitivity torsion sensor based on the helical long-period grating (HLPG) inscribed in the cladding-etched double cladding fiber (DCF). The torsion sensitivity has been greatly improved by reducing the cladding diameter of the DCF, from 0.342 to 1.162 nm/(rad/m), which is one order of magnitude higher than that of the conventional long-period fiber grating (LPFG). The cladding mode coupling characteristics during the etching process are also investigated experimentally. The DCF-HLPG has a low strain and temperature sensitivity, and the maximum strain sensitivity is only about 0.0022 nm/ $\mu \varepsilon $ . The proposed DCF-HLPG has a potential application as a high-sensitivity torsion sensor with low strain and temperature crosstalk.

Location-controlled single grains were obtai- ned through amorphous silicon grown on substrates embedded with microstructure called grain filters (GFs) using long-pulse green laser annealing. This work demonstrates the significant influence of GF spacing and size on grain quality. Accomplished results in this work evidenced that defects like grain boundary could be decreased by manipulating the GF spacing and dimensions to achieve high-integrity single grains with large grain sizes, which is beneficial for device fabrication. Thin-film transistors (TFTs) (W/L = 0.18/ $0.22~\mu \text{m}$ ) fabricated on the grains under optimized conditions exhibit excellent electrical performance, with an extracted field-effect mobility of 336 cm2/V-s and an exceptional ${I}_{\text {on}}/{I}_{\text {off}}$ ratio of $5.16\times 10^{{6}}$ .

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In this article, a refined ladder transmission line model (R-LTLM) test structure capable of extracting significantly low specific contact resistivity ( $\rho _{c}$ ) eliminating parasitic metal resistance is proposed. Theoretical derivations, technology computer-aided design (TCAD) simulations, and experiments are performed to verify the validity and superiority of R-LTLM. Compared with refined transmission line model (RTLM) and ladder transmission line model (LTLM), R-LTLM not only achieves higher extraction accuracy than RTLM but also relieves the impact of process variation during the formation of contact area patterns and contact spacings. Moreover, the impacts of process variation on the extraction of $\rho _{c}$ using LTLM and R-LTLM are analyzed. As for experimental verification, RTLM, LTLM, and R-LTLM test structures are fabricated to extract $\rho _{c}$ of TiSix/ $\text{n}^{+}$ -Si Ohmic contacts. Results show that R-LTLM can eliminate parasitic metal resistance, leading to higher extraction accuracy than RTLM.

This paper is devoted to the research of full implication triple I method under Pythagorean fuzzy environment. We first propose the concepts of Pythagorean t-norm, Pythagorean t-conorm, residual Pythagorean fuzzy implication operator (RPFIO) and Pythagorean fuzzy biresiduum. The full implication triple I method for Pythagorean fuzzy modus ponens (PFMP) and Pythagorean fuzzy modus tollens (PFMT) are also established. In addition, the properties of full implication triple I method of PFMP and PFMT models including the robustness, continuity and reversibility are analyzed. Finally, a practical problem is discussed to demonstrate the effectiveness of the Pythagorean fuzzy full implication multiple I method in medical diagnosis. The advantages of the new method are also explained. Overall, compared with the existing methods, the proposed methods are based on logical reasoning rather than using aggregation operators, so they can more accurately and completely express decision information.

Nonalcoholic fatty liver disease (NAFLD) has become a common chronic liver disease that is harmful to human health. Moreover, there is currently no FDA-approved first-line drug for the treatment of nonalcoholic steatohepatitis (NASH) or NAFLD. Traditional Chinese medicine (TCM) is widely used to ameliorate liver diseases, such as the traditional ancient recipe called Three Flower Tea (TFT), which consists of double rose (Rosa rugosa), white chrysanthemum (Chrysanthemum morifolium), and Daidaihua (Citrus aurantium). However, the mechanisms of the action of TFT are not clear. Therefore, this study aimed to elucidate the mechanisms of TFT against NAFLD in high-fat diet (HFD)-induced rats.

The excellent performance and safety of direct formic acid fuel cells (DFAFCs) promote them as potential power sources for portable electronic devices. However, their real application is still highly challenging due to the poor power performance and high complexity in the fabrication of catalyst electrodes. In this work, we demonstrate a new gas diffusion electrode (GDE) with ultrathin PtCu alloy nanowire (NW) arrays in situ grown on the carbon paper gas diffusion layer surface. The growing process is achieved by a facile template- and surfactant-free self-growth assisted reduction method at room temperature. A finely controlled ion reduction process tunes the nucleation and crystal growth of Pt and Cu leading to the formation of alloy nanowires with an average diameter of about 4 nm. The GDE is directly used as the anode for DFAFCs. The results in the half-cell GDE measurement indicate that the introduction of Cu in PtCu NWs boosts the direct oxidation pathway for formic acid. The Pt3Cu1NW GDE shows a 2.4-fold higher power density compared to the Pt NW GDE in the membrane electrode assembly test in single cells.

Recently, the tetrahedral Ti4L6cage (L = embonate) has been applied as the starting material to realize coordination assembly with transition and rare-earth ornoble metal ions through a two-step reaction. In this work, by employing the Ti4L6cages to assemble with alkaline-earth metal ions (such as Mg2+, Ca2+and Ba2+) under different solvothermal conditions, a series of Ti4L6-based structures from simple cages to 1D chain, 2D layer and 3D framework have been synthesized and structurally characterized. In addition, thermal stability, phase purity, UV-vis absorption spectrum, the fluorescent and third-order nonlinear-optical properties are also investigated.

A series of novel S-DACO derivatives were designed by structure-based linker optimization strategy. Most compounds showed potential activities against HIV-1 with IC50values ranging from 7.55 μmol/L to 0.018 μmol/L. Preliminary SAR and molecular modeling of these novel congeners were investigated.

A 4 × 4 invertible circulant matrix on GF(28) can represent the Mixcolumn operation of AES, which plays an important role as a confusion operation. Starting from the analysis of the Mixcolumns operation of AES, we have mainly research the properties of circulant matrix over finite field, and present a novel algorithm that generates the 4 × 4 circulant inverse matrices and the 4 × 4 circulant matrices with the maximal branch number in this paper. At last, some characteristics of the orthormorphic or symmetrical circulant matrices to arrive at the maximal branch number have been discussed in this paper. An algorithm for generating the 4 × 4 orthormorphic circulant matrix with the maximal branch number is also obtained on the finite field. Furthermore, the conclusion is gained that the symmetrical matrix with maximal branch number does not exist.

This paper reports an efficient method of preparing porous polymeric microspheres by solvent evaporation in foam phase, in which phase separation between polymer and porogen occurs in foam phase instead of that in water phase by using the traditional solvent evaporation method. The method provides outstanding features, including being time-saving, of high-yield and able for continuous production, in which formation of porous polymeric microspheres finished within 3 min with a high production yield up to approximate 95 wt% and the process was able to be developed into a continuous process for production of porous polymeric microspheres. It was also universal to non-crosslinked polymers since the method is a development on the traditional emulsion solvent evaporation method. The new method is efficient and can be used potentially on the industrial scale for continuous production of porous polymeric microspheres.

A general and versatile strategy to prepare melamine-formaldehyde (MF) microcapsules encapsulating oil-based fragrances by combining solvent evaporation and in situpolymerization was proposed in this work. The oil-based fragrance was pre-encapsulated by an inner polyacrylate membrane viasolvent evaporation, followed by in situpolymerization of MF precondensates as an outer shell. The polyacrylate membrane is used as an intermediate bridging layer to stabilize the oil-based fragrance, and to provide driving forces for in situpolymerization of MF precondensates through electrostatic attractions between carboxyl groups and ammonium ions. It was demonstrated that MF microcapsules containing clove oil were prepared successfully. The amount and the composition of the intermediate polyacrylate bridging layer were critical. Smooth and sphere-shaped MF-clove oil microcapsules were prepared when the weight ratio of polyacrylate to clove oil was over 60 wt% and the concentration of acrylic acid (AA) increased to 10 wt% in polyacrylate. In addition, MF microcapsules containing sunflower oil and hexyl salicylate were prepared by using this method. The work suggests that this new approach can be potentially used to encapsulate various core materials, tuning the shell properties of microcapsules such as thickness, mechanical strength and release properties.

Background: S-dihydro-alkyloxy-benzyl-oxopyrimidines (S-DABOs) as non-nucleoside reverse transcriptase inhibitors have received considerable attention during the last decade due to their high potency against HIV-1. Methods: In this study, three-dimensional quantitative structure-activity relationship (3D-QSAR) of a series of 38 S-DABO analogues developed in our lab was studied using Comparative Molecular Field Analysis (CoMFA) and Comparative Molecular Similarity Indices Analysis (CoMSIA). The Docking/MMFF94s computational protocol based on the co-crystallized complex (PDB ID: 1RT2) was used to determine the most probable binding mode and to obtain reliable conformations for molecular alignment. Statistically significant CoMFA (q2=0.766 and r2=0.949) and CoMSIA (q2=0.827 and r2=0.974) models were generated using the training set of 30 compounds on the basis of hybrid docking-based and ligand-based alignment. Results: The predictive ability of CoMFA and CoMSIA models was further validated using a test set of eight compounds with predictive r2 pred values of 0.843 and 0.723, respectively. Conclusion: The information obtained from the 3D contour maps can be used in designing new SDABO derivatives with improved HIV-1 inhibitory activity.

Effective triage of high-risk human papillomavirus (hrHPV)+ women is warranted to avoid unnecessary referral and overtreatment. Molecular triage tests have recently begun to impact cervical intraepithelial neoplasia grade 3 (CIN3) or cervical cancer (CC), termed CIN3+, detection. We find that zinc finger protein 671 methylation (ZNF671m) test has superior performance for CIN3+ detection in all single molecular triage tests, including HPV16/18 genotyping, paired box gene 1 methylation (PAX1m), and ZNF671m, in the training set. Using ZNF671mtest instead of Thinprep cytologic test (TCT) as a single triage strategy or as a combined triage strategy with HPV16/18 genotyping has achieved comparable sensitivity but higher specificity for CIN3+ detection among 391 hrHPV+ women in the validation set. Little attention has been paid to the women with hrHPV− status but detected CIN3+. We find that the CIN3+ risk after a negative result could be reduced further by triage using ZNF671min hrHPV− patients.

Currently available deformability cytometry, combining microfluidics with the bright‐field high‐speed imaging system, has allowed label‐free mechanical characterizations of cells at a rate of hundreds of cells per second. However, the poor contrast between the signal and background under bright‐field imaging, especially for abnormal cells or cells treated with drugs, may produce artifacts during the recognition of cellular contours and subsequently bias the analysis of cellular deformability. In this study, a quantitative phase deformability cytometry (QPDC), constructed from a quantitative phase imaging system, is demonstrated with an improved signal‐to‐noise ratio of the acquired images and mitigated image artifacts, allowing a truthful illustration of cellular contours, especially for cells subjected to actin depolymerization. We have also demonstrated that the phase value extracted from captured images may provide an additional biophysical characteristic of cells. The presented QPDC platform is therefore expected to complement the existing deformability cytometry and expand the capacity of label‐free characterization of cells for biological and clinical applications. A quantitative phase deformability cytometry (QPDC) combines the microfluidics‐based deformability cytometry and a quantitative phase imaging system, aiming to improve the image quality. The improved signal‐to‐noise ratio of QPDC allows for a truthful illustration of cellular contours, especially for cells subjected to actin depolymerization. At the same time, the phase value extracted from the reconstructed phase map may provide an additional biophysical characteristic of cells.

Rhyzopertha dominicais one of the most important stored grain pests that seriously damage rice and wheat. At present, the method of controlling stored grain pests mainly relies on insecticide fumigation. However, the excessive use of pesticides not only leaves pesticide residues, with harmful effects on human health and the environment, but also induces insect resistance. Ozone is a strong oxidant with the characteristics of easy decomposition and without residue. Although ozone has been widely used in the food industry in recent years, research on the control of stored grain pests is limited. In this research, we used ozone treatment to control R. dominicaadults and explore the molecular mechanisms that affect them. Here, we found that ozone treatment on R. dominicaadults could decrease life span and increase malondialdehyde (MDA) content, as well as reduce activity of total superoxide dismutase (SOD) and catalase (CAT). Using RNA-seq technology, we identified 641 genes that were differentially expressed between ozone-treated and control R. dominicaadults [fold-change of ≥ 2 (q-value < 5%)]. When comparing ozone treatment with control R. dominicaadults, 330 genes were significantly upregulated and 311 were downregulated. RT-qPCR confirmed that 11 genes were differentially expressed in ozone-treated and control R. dominicaadults. These genes were involved in insect cuticle protein and antioxidant system. This research showed that ozone treatment could reduce the lifespan of R. dominicathrough antioxidant system. It is an environmentally benign method for the control of stored grain pests and has great development potential.

Two-photon photopolymerization (TPP) has recently become a popular method for the fabrication of three-dimensional (3D) micro- and nanostructures. The reproduction fidelity of the designed micro- and nanostructures is influenced by experimental writing conditions, including laser power, exposure time, etc. To determine the appropriate writing parameters, characterization of morphological features and surface roughness during the experiment is needed. Traditional characterization methods for TPP, e.g., scanning electron microscopy and atomic force microscopy, have limited speed and cannot study internal structures without invasive approaches. Optical diffraction tomography (ODT) is an emerging label-free 3D imaging technique based on reconstructing the object’s 3D refractive index (RI) distribution with diffraction-limited resolution. Here, we propose a non-invasive solution to fully characterize the TPP-fabricated structures using a high-speed ODT technique, which can eliminate the need for complex sample preparation, such as fluorescence labelling or metal-coating, and achieve a full 3D measurement time of 6 ms. By visualizing and studying different TPP-fabricated structures, including embedded spirals and cubes, via the ODT system, the fabrication quality, including 3D morphological features, exposure levels, and surface roughness, can be examined quantitatively. The results suggest our method can effectively improve the fabrication quality and reproducibility of TPP, generating impacts on the nanofabrication community.

In this study, formulation of latex with methyl methacrylate (MMA) as a function of surfactant concentration ([S]) under critical micelle concentration (CMC) was investigated to explore the nucleation mechanism and the key to control the particle number (Np) of latex in emulsion polymerization. Influences of surfactant concentration [S] on the conversion of monomer, particle size (PS), Np, and surfactant surface coverage (θ) were studied, as well. Flocculation nucleation was considered as the main mechanism to generate particle nuclei when [S] was much less than CMC. The nucleation mechanism experienced an evolution of a flocculation nucleation-dominated region ([S] < 3.3 mmol L−1) to a micellar nucleation-dominated region ([S] > 3.3 mmol L−1). The contribution ratio of the flocculation nucleation was 86 % compared with the micellar nucleation. The particle number (Np) was found to be controlled by the combination of micellar and flocculation nucleation-dominated regions under CMC, and the regulation range was about 1–6. The results can be used to guide the preparation of a bimodal high solid content (HSC) latex by creating a population of small particles in the presence of an initial population of larger ones in a controllable way. In this way, a controllable amount of large latex particles were prepared using a high emulsifier concentration, at first, and then the second population of small particles was formulated by secondary nucleation at a proper time through controlling surfactant concentration at a low level, followed by the growth of the two groups of the particles, and then the bimodal HSC latex can be prepared at low viscosity.

Abstract: Probability distributions of surface wind speeds (SWS) near coastal regions are needed for applications such as estimating offshore wind power and ocean surface fluxes and for offshore wind risk assessments. Ocean surface wind speed probability distribution (PDF) is characterized using three-year QuikSCAT and AIRS satellite observations in the southeast Pacific of marine stratus and stratocumulus (MSC) regions. Seasonal variation is removed from wind statistics. It was found that the observed SWS standard deviation has a linear positive relationship with its mean SWS; while the SWS skewness decreases with mean SWS in regimes of strong winds and increases with mean SWS in regimes of weak winds. A simple 1D conceptual model is developed near the Peruvian region, which successfully reproduces the observed relationship between higher moments of SWS and its mean value. The model based physical picture among ocean surface winds, SST, and marine boundary clouds are supported by three-year QuikSCAT surface wind observations and fifteen-year ERA40 re-analysis data. Model sensitive tests suggest that large-scale divergence, and strengths of momentum and cloud fluctuations have significant effects on the ocean SWS-PDF in marine stratus and stratocumulus regions.

Abstract: The relationship between surface latent heat flux and the lower-tropospheric stability (LTS) is examined using ERA-40 reanalysis, NCEP reanalysis and COADS (Comprehensive Ocean-Atmosphere Data Set) ship data in two southern subtropical marine stratus and stratocumulus regions. The change of surface latent heat flux with LTS is determined by a comparison of the correlation of LTS with surface wind speed and with near surface humidity difference. At intermediate LTS (10 K-15 K), both surface evaporation and downward surface radiation flux amplify small LTS perturbations due to the surface wind-LTS relationship and cloud-radiation feedback. At high LTS, surface latent heat flux exceeds its peak value and becomes a regulating mechanism to keep LTS at its commonly observed equilibrium value. Surface radiation flux is seen to decrease at a smaller rate with LTS than surface latent heat flux. By applying the regulating effect of LTS on near surface humidity differences, monthly surface latent heat flux can be better represented.

Summary. A series of 6-naphthylmethyl substituted HEPT analogues bearing a ß-carbonyl and a terminal phenyl ring or ester groups on the N-1 side chain of uracil were synthesized, and the in vitro anti-HIV activity was evaluated. Most of these HEPTs were considerably less potent and selective or inactive, only a few compounds showed moderate or high activity against HIV-1. The results demonstrated that the anti-HIV-1 activity of 6-naphthylmethyl substituted HEPT analogues was diminished or eliminated when the ß-oxygen of N-1 side chain was replaced by a carbonyl group.

Objective In this study, we aimed to determine the effects of physical therapy intervention on mental function in patients with stroke.Methods In this retrospective experimental study, we included 134 patients previously diagnosed with anxiety and depression who presented to our outdoor physical therapy clinic with hemiplegia owing to stroke during 2016 to 2018. The main interventions were neurodevelopmental techniques, strength training, stationary cycling, and shoulder wheel exercise. The treatment duration was 6 months, 5 days a week. Key outcome measurement tools included the Patient Health Questionnaire-9 (PHQ-9), Disability Rating Scale (DRS), and Functional Independent Measure (FIM). Baseline and post-interventional measurements were compared using a paired-sample t-test.Results Baseline scores on the PHQ-9, DRS, and FIM were 24.77±1.24, 19.67±1.25, and 20.77±1.74, respectively; post-intervention scores on these three scales were 9.08±0.49, 7.78±1.49, and 82.52±10.03 respectively. In the comparison, significant differences were observed between baseline and post-interventional scores.Conclusion We found that physiotherapy interventions improved motor function in patients with stroke as well as their mental function. Patients with stroke with impaired mental function can improve by participating in a physiotherapy treatment program.

For Abstract see ChemInform Abstract in Full Text.