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1.
Int J Legal Med ; 136(6): 1621-1636, 2022 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-36180601

RESUMO

The present study combined three-dimensional (3D) motion capture with finite element simulation to reconstruct a real shaking adult syndrome (SAS) case and further explore the injury biomechanics of SAS. The frequency at which an adult male can shake the head of another person, head-shaking amplitude, and displacement curves was captured by the VICON 3D motion capture system. The captured shaking frequency and shaking curve were loaded on the total human model for safety (THUMS) head to simulate the biomechanical response of brain injury when a head was shaken in anterior-posterior, left-right, and left anterior-right posterior directions at frequencies of 4 Hz (Hz), 5 Hz, 6 Hz, and 7 Hz. The biomechanical response of the head on impact in the anterior, posterior, left, left anterior, and right posterior directions at the equivalent velocity of 6 Hz shaking was simulated. The violent shaking frequency of the adult male was 3.2-6.8 Hz; head shaking at these frequencies could result in serious cerebral injuries. SAS-related injuries have obvious directionality, and sagittal shaking can easily cause brain injuries. There was no significant difference between the brain injuries caused by shaking in the simulated frequency range (4-7 Hz). Impact and shaking at an equivalent velocity could cause brain injuries, though SAS more commonly occurred due to the cumulative deformation of brain tissue. Biomechanical studies of SAS should play a positive role in improving the accuracy of forensic identification and reducing this form of abuse and torture in detention or places of imprisonment.


Assuntos
Lesões Encefálicas Traumáticas , Síndrome do Bebê Sacudido , Adulto , Anodontia , Fenômenos Biomecânicos , Mama/anormalidades , Hemorragia Cerebral , Displasia Ectodérmica , Análise de Elementos Finitos , Humanos , Obstrução dos Ductos Lacrimais , Deformidades Congênitas dos Membros , Masculino , Modelos Biológicos , Unhas Malformadas , Transtornos da Pigmentação , Síndrome do Bebê Sacudido/etiologia
2.
Front Plant Sci ; 15: 1434926, 2024.
Artigo em Inglês | MEDLINE | ID: mdl-39104846

RESUMO

Introduction: High-yield and high-quality production of silage maize in cold regions is crucial for ensuring the sustainable development of livestock industry. Methods: This study first conducted an experiment to select the optimized silage maize varieties and densities using a split-plot design. The tested maize varieties were Xuntian 3171, Xuntian 16, Xunqing 858, and Fengtian 12, with each variety planted at densities of 67,500, 79,500, and 90,000 plants ha-1. Following the variety and density selection, another experiment on optimizing nitrogen management for silage maize was carried out using a completely randomized design: no nitrogen fertilizer (T1), applying urea-N 320 kg ha-1 (T2), applying urea-N 240 kg ha-1 (T3), applying polymer-coated urea-N 240 kg N ha-1 (T4), and ratios of polymer-coated urea-N to urea-N at 9:1 (T5), 8:2 (T6), 7:3 (T7), and 6:4 (T8). T5-T8 all applied 240 kg N ha-1. The yield and quality of silage maize, nitrogen use efficiency and balance, and economic benefits were evaluated. Results: Results showed that Xunqing 858 had significantly higher plant height (8.7%-22.6% taller than the other three varieties) and leaf area (30.9% larger than Xuntian 3171), resulting in yield 11.5%-51.6% higher than the other three varieties. All varieties achieved maximum yields at a planting density of 79,500 plants ha-1. Integrated management strategy 7 (T7: Xunqing 858, 79,500 plants ha-1, polymer-coated urea-N to urea-N ratio of 7:3) achieved the highest yield of 73.1 t ha-1, a 6.1%-58.1% increase over other treatments. This strategy also produced the highest crude protein (11.1%) and starch (19.1%) contents, and the lowest neutral detergent fiber content (50.6%), with economic benefits improved by 10.3%-97.8% compared to other strategies. Additionally, T7 improved nitrogen use efficiency by 15.4%-94.5%, reduced soil nitrate leaching by 4.4%-36.5%, and decreased nitrogen surplus by 7.0%-46.6%. Conclusion and discussion: Comprehensive analysis revealed that the integrated management strategy 7 significantly improved silage maize yield and quality in cold regions while enhancing nitrogen use efficiency and reducing the risk of nitrate leaching, aligning with green agriculture development requirements. These findings will provide vital theoretical insights and practical guidance for high-yield and high-quality silage maize production in cold regions worldwide.

3.
J Physiol Biochem ; 80(1): 113-126, 2024 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-37882938

RESUMO

The global prevalence and incidence of non-alcoholic fatty liver disease (NAFLD) are exhibiting an increasing trend. NAFLD is characterized by a significant accumulation of lipids, though its underlying mechanism is still unknown. Here we report that high-fat diet (HFD) feeding induced hepatic steatosis in mice, which was accompanied by a reduction in the expression and function of hepatic TRPV2. Moreover, conditional knockout of TRPV2 in hepatocytes exacerbated HFD-induced hepatic steatosis. In an in vitro model of NAFLD, TRPV2 regulated lipid accumulation in HepG2 cells, and TRPV2 activation inhibited the expression of the cellular senescence markers p21 and p16, all of which were mediated by AMPK phosphorylation. Finally, we found that administration of probenecid, a TRPV2 agonist, impaired HFD-induced hepatic steatosis and suppressed HFD-induced elevation in p21 and p16. Collectively, our findings imply that hepatic TRPV2 protects against the accumulation of lipids by modulating p21 signalling.


Assuntos
Canais de Cálcio , Dieta Hiperlipídica , Hepatopatia Gordurosa não Alcoólica , Canais de Cátion TRPV , Animais , Camundongos , Dieta Hiperlipídica/efeitos adversos , Regulação para Baixo , Hepatócitos/metabolismo , Metabolismo dos Lipídeos , Lipídeos , Fígado/metabolismo , Camundongos Endogâmicos C57BL , Hepatopatia Gordurosa não Alcoólica/etiologia , Hepatopatia Gordurosa não Alcoólica/metabolismo , Canais de Cátion TRPV/genética , Canais de Cátion TRPV/metabolismo , Canais de Cálcio/genética , Canais de Cálcio/metabolismo , Inibidor de Quinase Dependente de Ciclina p21/metabolismo
4.
ChemSusChem ; 16(2): e202201801, 2023 Jan 20.
Artigo em Inglês | MEDLINE | ID: mdl-36401564

RESUMO

Solid lithium batteries (SLBs) have received much attention due to their potential to achieve secondary batteries with high energy density and high safety. The solid electrolyte (SE) is believed to be the essential material for SLBs. Among the recent SEs, composite electrolytes have good interfacial compatibility and customizability, which have been broadly investigated as promising contenders for commercial SLBs. The high Li+ transference number (t Li + ${{_{{\rm Li}{^{+}}}}}$ ) of composite electrolytes is critically important concerning the power/energy density and cycling life of SLBs, however, which is often overlooked. This Review presents a current opinion on the key factors in high t Li + ${{_{{\rm Li}{^{+}}}}}$ composite electrolytes, including polymers, Li-salts, inorganic fillers, and additives. Various strategies concerning providing a continuous pathway for Li-ions and immobilizing anions via component interaction are discussed. This Review highlights the major obstacles hindering the development of high t Li + ${{_{{\rm Li}{^{+}}}}}$ composite electrolytes and proposes future research directions for developing composite electrolytes with high t Li + ${{_{{\rm Li}{^{+}}}}}$ .

5.
ACS Appl Mater Interfaces ; 14(21): 24929-24937, 2022 Jun 01.
Artigo em Inglês | MEDLINE | ID: mdl-35594362

RESUMO

High-energy density and safe solid lithium batteries call for cathodes with high capacity and good kinetic properties. In this work, LiNi0.6Co0.2Mn0.2O2 (NCM622) cathodes are coated with the ionic-electronic dual-conductive polymers composed of poly(ethylene glycol) (PEG)-doped polyaniline (PANI). Scanning electron microscopy, transmission electron microscopy, Fourier transform infrared, and thermogravimetric analysis reveal that the dual-conductive polymers are homogeneously coated on the surfaces of NCM622 cathodes with a thickness of approximately 10 nm. The solid-state lithium batteries consisting of the NCM622 cathodes coated with PANI-PEG show a specific capacity of 158 mA h g-1 and a retention rate of 88% after 100 cycles at the rate of 0.1 C and room temperature, which are superior to the discharge capacity of 153 mA h g-1 and capacity retention of 59% after 100 cycles for the batteries with the pristine NCM622 cathodes. Moreover, the cells with the coated cathodes display a better rate performance of 84 mA h g-1 at 1 C than those with the uncoated ones which show a rate performance of 11 mA h g-1 at 1 C.

6.
Chem Commun (Camb) ; 58(62): 8638-8641, 2022 Aug 02.
Artigo em Inglês | MEDLINE | ID: mdl-35820145

RESUMO

An ionic-electronic dual-conductive polymer, fabricated by doping polyethylene glycol into polyaniline, is used to modify LiCoO2 cathodes for solid lithium batteries. The polymer enables uniform and fast conductive networks in cathodes and stabilizes the generation of cathode interface layers. The cell maintains high cycle stability of 91.8% capacity retention after 200 cycles.

7.
ACS Appl Mater Interfaces ; 12(41): 46231-46238, 2020 Oct 14.
Artigo em Inglês | MEDLINE | ID: mdl-32955855

RESUMO

The demand for solid lithium batteries with high energy density and safety boosts the development of solid-state electrolytes in which composite membrane electrolytes consisting of polymers and ceramic fillers are attractive. As the common ceramic filler, perovskite-structured Li0.33La0.557TiO3 (LLTO) has great advantage on cost and environmental friendliness by using earth-abundant raw materials in the production. Nevertheless, the chemical instability of LLTO against Li-metal hinders its application. Herein, LLTO particles are coated by biodegradable polydopamine (PDA) layers and united with poly(vinylidene fluoride) (PVDF) to prepare composite electrolytes which perform superior stability against Li-metal. Besides, PVDF:LLTO membranes are assembled at cathode sides and show high voltage tolerance. The Li/Ni0.6Mn0.2Co0.2O2 cells with bilayer membrane electrolytes can deliver the specific capacity of 158.2 mAh g-1 and maintain 83% capacity after 100 cycles at 0.1 C. Furthermore, based on the bilayer membranes with outstanding flexibility and stretchability, the cells can even survive under several extreme conditions, such as bending, twisting, crimping, and stretching. This study offers an environmentally friendly strategy to improve the stability of LLTO against Li and sheds light on the development of cost-effective solid electrolytes.

8.
Polymers (Basel) ; 12(6)2020 Jun 10.
Artigo em Inglês | MEDLINE | ID: mdl-32532045

RESUMO

Composite electrolytes consisting of polymers and three-dimensional (3D) fillers are considered to be promising electrolytes for solid lithium batteries owing to their virtues of continuous lithium-ion pathways and good mechanical properties. In the present study, an electrolyte with polyethylene oxide-lithium (bis trifluoromethyl) sulfate-succinonitrile (PLS) and frameworks of three-dimensional SiO2 nanofibers (3D SiO2 NFs) was prepared. Taking advantage of the highly conductive interfaces between 3D SiO2 NFs and PLS, the total conductivity of the electrolyte at 30 °C was approximately 9.32 × 10-5 S cm-1. With a thickness of 27 µm and a tensile strength of 7.4 MPa, the electrolyte achieved an area specific resistance of 29.0 Ω cm2. Moreover, such a 3D configuration could homogenize the electrical field, which was beneficial for suppressing dendrite growth. Consequently, Li/LiFePO4 cells assembled with PLS and 3D SiO2 NFs (PLS/3D SiO2 NFs), which delivered an original specific capacity of 167.9 mAh g-1, only suffered 3.28% capacity degradation after 100 cycles. In particular, these cells automatically shut down when PLS was decomposed above 400 °C, and the electrodes were separated by the solid framework of 3D SiO2 NFs. Therefore, the solid lithium batteries based on composite electrolytes reported here offer high safety at elevated temperatures.

9.
ACS Appl Mater Interfaces ; 12(41): 46162-46169, 2020 Oct 14.
Artigo em Inglês | MEDLINE | ID: mdl-32935964

RESUMO

Flexible membrane electrolytes consisting of Li6.4La3Zr1.4Ta0.6O12 (LLZTO) fillers in poly(propylene carbonate) (PPC) are considered promising for developing solid lithium batteries with high energy density and safety. However, LLZTO particles tend to agglomerate owing to their high surface energy, especially concerning their distribution in PPC that has low surface energy. Moreover, basic LLZTO particles attack PPC, resulting in its decomposition. Such problems make it difficult to achieve membrane electrolytes of PPC/LLZTO with high conduction and stability. In this work, continuous polydopamine (PDA) layers with a thickness of 4 nm are coated on LLZTO particles. Characterized by synchrotron X-ray microtomography and scanning electron microscopy, the PDA-coated LLZTO particles show homogeneous dispersion in PPC, which is attributed to the reduced surface energy of the LLZTO particles. Besides, this coating hinders the reaction between LLZTO and PPC, which improves the chemical stability of the membrane electrolytes. Consequently, the cells based on membrane electrolytes with PDA-coated LLZTO particles in PPC show improved electrochemical performance and cycling stability. These results demonstrate that the strategy of coating basic LLZTO particles is powerful for enhancing their usability in the high-performance membrane electrolytes for solid lithium batteries.

10.
Leg Med (Tokyo) ; 45: 101697, 2020 Apr 07.
Artigo em Inglês | MEDLINE | ID: mdl-32305675

RESUMO

The finite element (FE) method can potentially help in reconstructing skull fracture biomechanisms, enabling differentiation of the injury patterns caused by traffic accidents. This study aims to (1) reconstruct a motorcycle driver-car accident case using the total human model for safety and FE simulations; and (2) analyze the biomechanisms of fatal ring fractures in the motorcyclist's skull base to determine if the fatal craniocerebral injuries were caused by a fall onto the highway after hitting a pedestrian or by the subsequent impact of a car. We simulated a series of loading scenarios of falls onto the road and impacts by a car, with and without a helmet being used. We reconstructed the injury processes and compared the biomechanics results to the skull tolerance limit. For the scenario of falling with a helmet, the Von-Mises stress around the foramen magnum indicated ring fractures with a slight fracture at the impact site, consistent with that detected in a traditional forensic pathology autopsy. Moreover, we found that a helmet can significantly protect the skull by controlling the increase in stress around the impact site. However, it has very little effect on the skull base, neck, or cervical spine. We determined that the characteristic ring fracture was most probably caused by the fall onto the highway. Thus, the subsequent car accident did not contribute to the motorcyclist's death. Our study demonstrates that the FE model and method can explore injury biomechanisms, assisting in the identification of injury patterns in forensic practices.

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