On-chip multi-trap optical tweezers based on a guided wave-driven metalens.

Optical tweezer arrays (OTAs) have emerged as a powerful tool for quantum simulation, quantum computation, and quantum many-body physics. Conventional OTAs require bulky and costly optical components to generate multiple optical traps, such as spatial light modulators (SLMs). An integrated way to achieve on-chip OTAs is a sought-after goal for compact optical manipulation. In this Letter, we have numerically demonstrated compact on-chip multi-trap optical tweezers based on a guided wave-driven metalens. The presented on-chip optical tweezers are capable of capturing multiple polystyrene nanospheres in parallel. Moreover, we proposed an analytical design method to generate customized focal points from the integrated photonics chip into free space. Different trapping patterns are demonstrated to validate our proposed off-chip emission scheme. Our approach offers a promising solution to realize on-chip optical tweezers and provides a prospective way to realize elaborate emission control of guided waves into free-space beams.

[Analysis of clinical characteristics and risk factors of early heat stroke-related acute liver injury].

OBJECTIVE: To analyze the clinical characteristics and risk factors of early acute liver injury in patients with heat stroke (HS), and to provide basis for early identification of HS-related liver injury and its pathogenesis in clinical practice. METHODS: The clinical data of patients with HS admitted to the department of critical care medicine of Haian People's Hospital from June 2015 to August 2022 were retrospectively analyzed. The patients with HS were divided into early liver injury group and early non-liver injury group according to the occurrence of acute liver injury within 24 hours of admission. The differences of basic data, clinical data, laboratory indexes and clinical outcomes of the two groups were analyzed. Logistic regression was used to analyze the risk factors for early HS-related acute liver injury, and receiver operator characteristic (ROC) curves were drawn to evaluate their value in predicting the occurrence of early HS-related acute liver injury. RESULTS: A total of 76 patients with HS were enrolled, and 46 patients with acute liver injury, accounting for 60.53%. In the early liver injury group, 14 patients (30.43%) had elevated aminotransferase alone, 9 patients (19.57%) had elevated total bilirubin (TBil) alone, and 23 patients (50.00%) had elevated both aminotransferase and TBil. Among the patients with elevated aminotransferases, 24 patients (64.87%) had mild elevation, 5 patients (13.51%) had moderate elevation, 8 patients (21.62%) had severe elevation. Compared with the early non-liver injury group, acute physiology and chronic health evaluation II (APACHE II), sequential organ failure assessment (SOFA), arterial blood lactate (Lac), interleukin-6 (IL-6), procalcitonin (PCT), alanine aminotransferase (ALT), aspartate aminotransferase (AST), TBil, γ-gamma glutamyl transferase (γ-GGT), lactate dehydrogenase (LDH), creatine kinase (CK), MB isoenzyme of creatine kinase (CK-MB), cardiac troponin I (cTnI), myoglobin (MYO), N-terminal B-type pro-brain natriuretic peptide (NT-proBNP), prothrombin time (PT), activated partial thromboplastin time (APTT), D-dimer in the early liver injury group were significantly increased, while platelet count (PLT) were significantly decreased within 24 hours after admission, the 28-day mortality was significantly increased [28.26% (13/46) vs. 6.67% (2/30)], and the differences were statistically significant (all P < 0.05). Univariate Logistic regression analysis showed that APACHE II score, SOFA score, PLT, Lac, IL-6, PCT, γ-GGT, LDH, CK, CK-MB, cTnI, MYO, PT, APTT, D-dimer were risk factors of early HS-related acute liver injury (all P < 0.05). Multivariate Logistic regression analysis showed that PLT, IL-6, and LDH were independent risk factors of early HS-related acute liver injury [odds ratio (OR) and 95% confidence interval (95%CI) were 0.986 (0.974-0.998), 1.027 (1.012-1.041), and 1.002 (1.000-1.004), all P < 0.05]. The ROC curve analysis showed that the area under the ROC curve (AUC) of PLT, IL-6 and LDH for predicting the occurrence of early HS-related acute liver injury was 0.672 (95%CI was 0.548-0.797), 0.897 (95%CI was 0.824-0.971) and 0.833 (95%CI was 0.739-0.927), respectively. IL-6 had the highest predictive value for early HS-related liver injury. When the optimal diagnostic threshold of IL-6 was 48.25 ng/L, the sensitivity was 95.7%, the specificity was 73.3%, and the predictive value of PLT was the lowest. CONCLUSIONS: The early HS-related liver injury is mainly manifested as the simultaneous elevation of aminotransferase and TBil, and most of cases are mild liver injury. PLT, IL-6 and LDH are independent risk factors of early HS-related acute liver injury.

White blood cell count combined with LDL cholesterol as a valuable biomarker for coronary artery disease.

OBJECTIVE: Inflammation and dyslipidemia are important pathophysiological bases for the occurrence and development of coronary artery disease (CAD); however, combination of these two entities is rarely used to diagnose CAD and its severity. Our aim was to determine whether the combination of white blood cell count (WBCC) and LDL cholesterol (LDL-C) can serve as a biomarker for CAD. METHODS: We enrolled 518 registered patients and measured serum WBCC and LDL-C on admission. The clinical data were collected, and the Gensini score was used to assess the severity of coronary atherosclerosis. RESULTS: WBCC and LDL-C levels in the CAD group were higher than in the control group ( P  < 0.01). Spearman correlation analysis showed that WBCC combined with LDL-C was positively correlated with the Gensini score ( r  = 0.708, P  < 0.01) and the number of coronary artery lesions ( r  = 0.721, P  < 0.01). Receiver operating characteristic curve analysis revealed that WBCC combined with LDL-C had a higher predictive value for CAD, severe CAD, and three-vessel CAD [area under the curve (AUC) values were 0.909, 0.867, and 0.811, respectively] than WBCC (AUC values were 0.814, 0.753, 0.716, respectively) and LDL-C (AUC values were 0.779, 0.806, 0.715, respectively) alone (all P  < 0.05). CONCLUSION: WBCC combined with LDL-C is correlated with the degree of coronary artery lesion. It had high sensitivity and specificity in the diagnosis of CAD, severe CAD, and three-vessel CAD.

An investigation of the psychological stress of medical staff in Shanghai shelter hospital during COVID-19.

Objective: The purpose of this study was to assess the psychological status of medical workers from other locations who helped support the fight against COVID-19 in Shanghai and to provide a basis for psychological crisis intervention plans under designated emergencies. Methods: While supporting the Shanghai Lingang Shelter Hospital, we investigated 1,097 medical staff from other cities working in the hospital. A questionnaire comprising the general information questionnaire, health questionnaire depression scale, generalized anxiety scale, insomnia severity index scale, and mental health self-assessment questionnaire was used. Results: There were no statistically significant differences in the incidence rates of anxiety, depression, and sleep disorders among subjects of different genders, ages, and educational levels. There were statistically significant differences in the incidences of anxiety, depression, stress response, and sleep disturbance among subjects with different levels of worry about COVID-19. Conclusion: During the COVID-19 pandemic, the Lingang Shelter Hospital team experienced more psychological pressure, suggesting that medical institutions should pay attention to the mental health of frontline medical workers during COVID-19 and prepare psychological intervention measures for team members.

An as-cast high-entropy alloy with remarkable mechanical properties strengthened by nanometer precipitates.

High-entropy alloys (HEAs) with good ductility and high strength are usually prepared by a combination of forging and heat-treatment processes. In comparison, the as-cast HEAs typically do not reach strengths similar to those of HEAs produced by the forging and heat-treatment processes. Here we report a novel equiatomic-ratio CoCrCuMnNi HEA prepared by vacuum arc melting. We observe that this HEA has excellent mechanical properties, i.e., a yield strength of 458 MPa, and an ultimate tensile strength of 742 MPa with an elongation of 40%. Many nanometer precipitates (5-50 nm in size) and domains (5-10 nm in size) are found in the inter-dendrite and dendrite zones of the produced HEA, which is the key factor for its excellent mechanical properties. The enthalpy of mixing between Cu and Mn, Cr, Co, or Ni is higher than those of mixing between any two of Cr, Co, Ni and Mn, which leads to the separation of Cu from the CoCrCuMnNi HEA. Furthermore, we reveal the nanoscale-precipitate-phase-forming mechanism in the proposed HEA.

An innovation for microstructural modification and mechanical improvement of TiAl alloy via electric current application.

In this article, microstructural evolution during the solidification of Ti-48Al-2Cr-2Nb with current density, as well as the formation mechanisms, are discussed, along with the impacts on microhardness and hot compression properties. The applied electric current promotes the solidification from the α primary phase to a largely ß solidification in Ti-48Al-2Cr-2Nb. With an increase in supercooling, the solidification process have a tendency to change from an α-led primary phase to (α + ß)-led primary phase. The primary dendrites, grain size, and lamellar spacing show a tendency to decrease first before increasing with increasing current density. Microhardness and high-temperature yield strength increase with a decrease in primary dendrite spacing, grain size, and lamellar spacing. Correlations between primary dendrite spacing, lamellar spacing, microhardness, yield strength, and current density are described by a fitting formula. An increase of α2 phase, due to the application of electric current, results in improved microhardness. The yield strength of Ti-48Al-2Cr-2Nb alloy increases linearly with microhardness. Yield stress increases with a decrease in microstructure parameters, in accordance with the Hall-Petch equation. The predominant modification mechanism with electric current application for TiAl solidification is the variation of supercooling and temperature gradients ahead of the mush zone due to Joule heating.

Effects of Tantalum on Microstructure Evolution and Mechanical Properties of High-Nb TiAl Alloys Reinforced by Ti2AlC.

Experiments have been carried out to study the relationship between the addition of tantalum and microstructure, especially the formation of the B2 phase in lamellar colonies. The mechanical properties, with different contents of Ta, were also measured. Ti46Al8Nb2.6CxTa alloys were prepared by casting with the content of Ta varying from zero to 1.0 at.%. Experimental results show that the B2 phase forms in lamellar colonies with the addition of Ta, and its content increases when the content of Ta increases. Meanwhile, the γ phase decreases and the lattice parameter of the α 2 phase increases. The size of the lamellar colony decreased from 29.9 to 21.6 µm. Ta dissolves into Ti2AlC by substitution, and its solubility is more than 1.1% tested by EDS. Nb, which is necessary for the formation of the B2 phase, comes from two aspects. The first is that Ta dissolves into the Ti2AlC and partly replaces the Nb atom and the second is the decrease in the γ phase because it has higher solid solubility for Nb. The increase in Nb in the liquid phase increases the composition supercooling and heteronucleation at the solidification front, which accounts for refining the lamellar colony. Room temperature compressive testing showed that the compressive strength and the strain increased when the Ta content increased up to 0.8% and then decreased. Improvement of the compressive properties resulted from the grain boundary strengthening and their decrease induced by more content of the B2 phase. Tensile properties, at elevated temperature, were improved with testing temperature increasing from 750 to 950°C, because solid solution strengthening is a major influence factor.

Overexpression of miR-582-5p Inhibits the Apoptosis of Neuronal Cells after Cerebral Ischemic Stroke Through Regulating PAR-1/Rho/Rho Axis.

OBJECTIVE: The purpose of this study was to explore the role of miR-582-5p/proteinase-activated receptors type I (PAR-1)/Rho/Rho in neuronal cell apoptosis after cerebral ischemic stroke (CIS). METHODS: In vivo mouse model of CIS induced by middle cerebral artery occlusion and in vitro model induced by oxygen-glucose deprivation/reoxygenation (OGD/R) in N2A cells was established. The expressions of miR-582-5p, PAR-1, RhoA, and ROCKII in brain tissues and N2A cells were detected. Neuronal cell apoptosis was detected by flow cytometry. RESULTS: We found that miR-582-5p expression was decreased and the expressions of PAR-1, RhoA, and ROCKII were increased in CIS mice and OGD/R model. Moreover, miR-582-5p negatively regulated PAR-1, and overexpression of miR-582-5p inhibited the activation of Rho/Rho pathway by downregulating PAR-1, thus reducing OGD/R-induced neuronal cell apoptosis. CONCLUSIONS: Our results suggested that miR-582-5p overexpression could regulate Rho/Rho-kinase signaling pathway via targeting PAR-1, thereby governing the apoptosis of neuronal cells after CIS.

High-density deformation nanotwin induced significant improvement in the plasticity of polycrystalline γ-TiAl-based intermetallic alloys.

Intermetallic alloys with high melting point can mostly serve as promising high-temperature structural materials, but their intrinsic brittleness limits their further application. Herein, we developed a strategy to realize high strength and high plasticity simultaneously in Cr-rich γ-TiAl-based intermetallic alloys via introducing high-density deformation nanotwins. Non-equilibrium continuous casting followed by annealing in the (α + γ) phase region generated numerous Shockley partial dislocations and stacking faults as well as a number of α2 nanoparticles in the γ-TiAl phase. The substantial Shockley partial dislocations and stacking faults acting as effective heterogeneous nucleation sites favored the generation of high-density nanotwins in the as-annealed alloys during deformation, especially within the γ lamellae. This strategy can also be applied to other brittle alloys with a favorable twinning deformation mechanism and paves the way for the development of high-strength and high-ductility materials.

Effects and mechanism of ultrasonic irradiation on solidification microstructure and mechanical properties of binary TiAl alloys.

In spite of their high temperature and reactivity, the binary TiAl alloys are successfully imposed by the ultrasonic irradiation and the microstructure evolution, solidification behaviors and mechanical properties are elaborately investigated. After ultrasonic irradiation, a high quality ingot without shrinkage defects and element segregation is obtained and the coarse dendrite structure is well modified into fine non-dendrite globular grains. The coarse lamellar colony and lamellar space of Ti44Al alloy is refined from 685µm to 52µm and 1185nm to 312nm, respectively (similarly, 819µm to 102µm and 2085nm to 565nm for Ti48Al alloy). For Ti48Al alloy, the α peritectic phase is simultaneously precipitated from the melt as well as the ß primary phase before the peritectic reaction and the solidification is transformed into the mixed α-solidifying and ß-solidifying. Ultrasonic irradiation promotes the peritectic reaction and phase transformation completely and the phase constituent becomes more close to the equilibrium level. The compressive strength of Ti44Al and Ti48Al alloys are increased from 623MPa to 1250MPa and 980MPa to 1295MPa, respectively. The grain refinement and dendrite transformation enhance the grain boundary sliding improving the plastic deformation ability. Ultrasonic irradiation significantly accelerates the melt flow and solute redistribution and the main grain refinement mechanism is the cavitation-enhanced nucleation by inclusion activation and heightened supercooling.

Pyrolytic Temperature Dependent and Ash Catalyzed Formation of Sludge Char with Ultra-High Adsorption to 1-Naphthol.

Massively produced sewage sludge brings a serious problem to environment. Pyrolysis is a promising and bifunctional technology to dispose the sewage sludge and recover energy, in which a large amount of pyrolytic sludge char is also produced. In this study, we proposed a value-added utilization of sludge char. We prepared an adsorbent with ultrahigh capacity for hydrophobic organic pollutant (1-naphthol) by pyrolysis of sludge and removal of the ash moiety from the sludge char. The adsorptive behavior of the adsorbent is strongly dependent on the pyrolytic temperature of sludge, and the maximum adsorption capacity of 666 mg g(-1) was achieved at 800 °C, which is comparable to deliberately modified graphene. Further exploration indicated that the robust adsorption to 1-naphthol is attributed to the catalytic effect of ash in sludge which facilitated the formation of more orderly graphitic structures and aromaticity at high pyrolytic temperatures.

Self-heating co-pyrolysis of excessive activated sludge with waste biomass: energy balance and sludge reduction.

In this work, co-pyrolysis of sludge with sawdust or rice husk was investigated. The results showed that the co-pyrolysis technology could be used to dispose of the excessive activated sludge without external energy input. The results also demonstrated that no obvious synergistic effect occurred except for heat transfer in the co-pyrolysis if the co-feeding biomass and sludge had similar thermogravimetric characteristics. The experimental results combined with calculation showed that adding sawdust accounting for 49.6% of the total feedstock or rice husk accounting for 74.7% could produce bio-oil to keep the energy balance of the co-pyrolysis system and self-heat it. The sludge from solar drying bed can be further reduced by 38.6% and 35.1% by weight when co-pyrolyzed with rice husk and sawdust, respectively. This study indicates that sludge reduction without external heat supply through co-pyrolysis of sludge with waste biomass is practically feasible.

Mass production of chemicals from biomass-derived oil by directly atmospheric distillation coupled with co-pyrolysis.

Production of renewable commodity chemicals from bio-oil derived from fast pyrolysis of biomass has received considerable interests, but hindered by the presence of innumerable components in bio-oil. In present work, we proposed and experimentally demonstrated an innovative approach combining atmospheric distillation of bio-oil with co-pyrolysis for mass production of renewable chemicals from biomass, in which no waste was produced. It was estimated that 51.86 wt.% of distillate just containing dozens of separable organic components could be recovered using this approach. Ten protogenetic and three epigenetic compounds in distillate were qualitatively identified by gas chromatography/mass spectrometry and quantified by gas chromatography. Among them, the recovery efficiencies of acetic acid, propanoic acid, and furfural were all higher than 80 wt.%. Formation pathways of the distillate components in this process were explored. This work opens up a fascinating prospect for mass production of chemical feedstock from waste biomass.

Selectively improving the bio-oil quality by catalytic fast pyrolysis of heavy-metal-polluted biomass: take copper (Cu) as an example.

Heavy-metal-polluted biomass derived from phytoremediation or biosorption is widespread and difficult to be disposed of. In this work, simultaneous conversion of the waste woody biomass into bio-oil and recovery of Cu in a fast pyrolysis reactor were investigated. The results show that Cu can effectively catalyze the thermo-decomposition of biomass. Both the yield and high heating value (HHV) of the Cu-polluted fir sawdust biomass (Cu-FSD) derived bio-oil are significantly improved compared with those of the fir sawdust (FSD) derived bio-oil. The results of UV-vis and (1)H NMR spectra of bio-oil indicate pyrolytic lignin is further decomposed into small-molecular aromatic compounds by the catalysis of Cu, which is in agreement with the GC-MS results that the fractions of C7-C10 compounds in the bio-oil significantly increase. Inductively coupled plasma-atomic emission spectrometry, X-ray diffraction, and X-ray photoelectron spectroscopy analyses of the migration and transformation of Cu in the fast pyrolysis process show that more than 91% of the total Cu in the Cu-FSD is enriched in the char in the form of zerovalent Cu with a face-centered cubic crystalline phase. This study gives insight into catalytic fast pyrolysis of heavy metals, and demonstrates the technical feasibility of an eco-friendly process for disposal of heavy-metal-polluted biomass.