Publications by authors named "KeJian Chen"

Active faults along railways in the mountainous regions of western China pose significant challenges to bridge safety. To ensure the safe operation of long-span railway bridges under complex geological conditions, this study investigates the synthesis of artificial ground motions for bridges crossing strike-slip faults and analyzes their nonlinear seismic response. First, we develop a theoretical method for simulating high- and low-frequency seismic motions using a finite fault and an equivalent velocity pulse model.

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Increasing attention is being paid to the application potential of multi-functional reconfigurable metamaterials in intelligent communication, sensor networks, homeland security, and other fields. A polarization-independent multi-functional reconfigurable metasurface based on doped vanadium dioxide (VO) is proposed in this paper. It can be controlled to switch its function among three working modes: electromagnetically induced absorption (EIA), electromagnetically induced transparency (EIT), and asymmetrical absorption.

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Temperature is an important factor affecting the water purification performance of constructed wetland (CW). In the previous study, the combined measures of Iris sibirica and aeration at the bottom of the first quarter filtration chamber could improve the pollutant removal capacity of CW at low temperature. However, the mechanism between the combined measures of Iris sibirica and aeration on enhancing the performance of domestic sewage treatment is unclear.

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A transparent in visible wavelengths and ultrabroadband microwave meta-absorber (MMA) based on indium tin oxide (ITO) metasurfaces and a water layer is proposed. After optimizing a series of structural parameters, the proposed MMA can achieve ultrabroadband absorption with an absorption efficiency of more than 90%, covering the frequency range of 9.44-120.

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Objective: This study was performed to evaluate the effectiveness of social platform-based continuity of care in improving cognitive and prognostic effects of young age diabetic patients without diabetic retinopathy (DR).

Methods: A total of 88 young age diabetic patients admitted to the outpatient clinic of First Affiliated Hospital of Soochow University (Endocrine and Ophthalmology Outpatient) from January 2021 to May 2022 were recruited and assigned via random number table method to receive either routine follow-up care (routine group) or social platform-based continuity of care (WeChat group), with 44 patients in each group. Treatment compliance, cognitive-behavioral ability, self-care ability (self-care responsibility, self-care skills, self-status, knowledge of diabetic retinopathy), quality of life (physical function, psychosocial, symptom and visual function, social activity), and prognosis of the patients were analyzed to investigate the effectiveness of WeChat social platform-based continuity of care.

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In recent years, nanoparticles camouflaged by red blood cell membrane (RBCM) have become a potential nano-drug delivery platform due to their good biocompatibility and immune evasion capability. Here, a multifunctional drug nanocarrier based on RBCM camouflaged mesoporous silica nanorods (MSNR) is presented, which can be used in pH and near-infrared (NIR) light triggered synergistic chemo-photothermal killing of cancer cells. To fabricate such a nanocarrier, MSNR and RBCM were prepared by the sol-gel method and modified hypotonic lysis method, respectively.

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Background: The risk factors for skin injuries remain poorly understood in cancer patients with peripherally inserted central catheters (PICC). We herein aimed at exploring the effect of clinical factors on the risk of PICC-related skin injuries.

Methods: We included 1245 cancer patients with PICC from 16 hospitals in Suzhou, China.

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Background: This study aimed to evaluate the healing process of chronic wounds treated with hydrogel combined with antimicrobial protease dressing and emotional support intervention in patients taking immunosuppressive agents.

Cases: The case series involved 8 patients treated at a tertiary public hospital for 12 weeks. Data were analysed by SPSS version 27.

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This study investigated a novel magnesium carbon micro-electrolysis (Mg-C ME) system for strengthening the removal of phenolic compounds in wastewater. The effects of the Mg/C mass ratio, aeration intensity, initial pH and reaction time on the degradation of three phenolic compounds and the COD removal efficiency in the simulated wastewater were evaluated using one-factor-at-a-time (OFAT) method. The optimum values obtained for the Mg/C mass ratio, aeration intensity, initial pH and reaction time were 3:1, 4.

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In this paper, a chiral excitation method based on the asymmetric interface condition is proposed. The chiral characteristics of the metamaterials are affected by the difference in the environmental parameters of the front and rear surfaces. Thus, the device can achieve functional reconfiguration and two applications based on this mechanism are presented, one for sensing and the other for chiral switching.

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A reconfigurable metamaterial for chirality switching and selective intensity modulation is demonstrated experimentally. Through simple folding strategy, nonchiral state, single-band chiral states and dual-bands chiral states can be switched. Circular dichroism up to 0.

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Older adults generally experience difficulties with hearing. Age-related changes in the chemistry of central auditory regions, especially the chemistry underlying synaptic transmission between neurons, may be of particular relevance for hearing changes. In this study, we used quantitative microchemical methods to map concentrations of amino acids, including the major neurotransmitters of the brain, in all the major central auditory structures of young (6 months), middle-aged (22 months), and old (33 months old) Fischer 344 x Brown Norway rats.

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Background: Coagulopathy after injury contributes to hemorrhage and death. Treatment with specific coagulation factors could decrease hemorrhage and mortality. Our aim was to compare fibrinogen and prothrombin complex concentrate (PCC) in a rabbit model of hemorrhagic shock.

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Acoustic trauma often leads to loss of hearing of environmental sounds, tinnitus, in which a monotonous sound not actually present is heard, and/or hyperacusis, in which there is an abnormal sensitivity to sound. Research on hamsters has documented physiological effects of exposure to intense tones, including increased spontaneous neural activity in the dorsal cochlear nucleus. Such physiological changes should be accompanied by chemical changes, and those chemical changes associated with chronic effects should be present at long times after the intense sound exposure.

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Hypothesis: Magnetically susceptible PLGA nanoparticles will effectively target the round window membrane (RWM) for delivery of dexamethasone-acetate (Dex-Ac) to the scala tympani.

Background: Targeted delivery of therapeutics to specific tissues can be accomplished using different targeting mechanisms. One technology includes iron oxide nanoparticles, susceptible to external magnetic fields.

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Temporary vascular shunts (TVSs) are relied on frequently in the current military theater. Details of their physiology and outcome are of increasing interest and needed to further define their place in the management of trauma. This study was conducted using a porcine hemorrhagic shock model and aimed to 1) establish the time to failure of short, proximally placed vascular shunts; and 2) examine histological changes in the shunted artery.

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Exposure to intense sounds often leads to loss of hearing of environmental sounds and hearing of a monotonous tonal sound not actually present, a condition known as tinnitus. Chronic physiological effects of exposure to intense tones have been reported for animals and should be accompanied by chemical changes present at long times after the intense sound exposure. By using a microdissection mapping procedure combined with high-performance liquid chromatography (HPLC), we have measured concentrations of nine amino acids, including those used as neurotransmitters, in the cochlear nucleus, inferior colliculus, medial geniculate, and auditory cortex of hamsters 5 months after exposure to an intense tone, compared with control hamsters of the same age.

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We experimentally investigate the differences in the evolution of surface-microstructured silicon fabricated by femtosecond laser pulses with different wavelength as a function of irradiated laser energy. The results show that when laser energy absorbed by the silicon material is the same, laser pulses with a shorter wavelength can form the surface-microstructured silicon with less laser energy, while the corresponding spike height is much lower than that of laser pulses with a longer wavelength. This is because the penetration depth of the laser pulses increases exponentially at the increase of the laser wavelength.

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The purpose of this study was to reveal synaptic plasticity within the dorsal cochlear nucleus (DCN) as a result of noise trauma and to determine whether effective antioxidant protection to the cochlea can also impact plasticity changes in the DCN. Expression of synapse activity markers (synaptophysin and precerebellin) and ultrastructure of synapses were examined in the DCN of chinchilla 10 days after a 105 dB SPL octave-band noise (centered at 4 kHz, 6 h) exposure. One group of chinchilla was treated with a combination of antioxidants (4-hydroxy phenyl N-tert-butylnitrone, N-acetyl-l-cysteine and acetyl-l-carnitine) beginning 4 h after noise exposure.

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Objective. Inhibition of inflammation and free radical formation in the cochlea may be involved in antioxidant treatment in acute acoustic trauma. Procedure.

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Objective: Hair cell death caused by acute acoustic trauma (AAT) reaches a secondary maximum at 7-10 days after noise exposure due to a second oxidative stress. Therefore, this study tested the effects of a combination of hydroxylated alpha-phenyl-tert-butylnitrone (4-OHPBN), N-acetyl-L-cysteine (NAC) and acetyl-L-carnitine (ALCAR) on AAT when the duration of treatment was extended over the period of 7-10 days after noise exposure as well as when the initial treatment was delayed 24 to 48 h after noise exposure.

Methods: Thirty chinchilla were exposed to a 105 dB octave-band noise centred at 4 kHz for 6 h and received the following treatments: (1) noise + saline (2-5) 4-OHPBN (20 mg/kg) + NAC (50 mg/kg) + ALCAR (20 mg/kg) intraperitoneally injected beginning 24 or 48 h after noise exposure twice daily for the next 2, 8 or 9 days.

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Among ten sodium channel alpha-subunit genes mapped in human and mouse genomes, the SCN8A gene is primarily expressed in neurons and glia. Mice with two types of Scn8a null mutations--Scn8a ( med ) and Scn8a ( medTg )--live for only 21-24 days, but those with incomplete mutations-Scn8a ( medJ ) and Scn8a ( medJo )--and those with knockout of Scn8a only in cerebellar Purkinje cells live to adult age. We review here previous work on cerebellum and related regions of Scn8a mutant mice and include some newer immunohistochemical and microchemical results.

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Terahertz wave (THz) photoconductive (PC) antennas were fabricated on oxygen-implanted GaAs (GaAs:O) and low-temperature-grown GaAs (LT-GaAs). The measured cw THz power at 0.358 THz from the GaAs:O antenna is about twice that from the LT-GaAs antenna under the same testing conditions, with the former showing no saturation up to a bias of 40 kV/cm, while the latter is already beginning to saturate at 20 kV/cm.

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Acute acoustic trauma (AAT) results in oxidative stress to the cochlea through overproduction of cellular reactive oxygen, nitrogen, and other free radical species appearing from 1 h to 10 days after noise exposure. It has been shown that N-acetyl-L-cysteine (NAC), a glutathione prodrug, and acetyl-L-carnitine (ALCAR), a mitochondrial biogenesis agent, are effective in reducing noise-induced hearing loss. Phenyl N-tert-butylnitrone (PBN), a nitrone-based free radical trap, appears to suppress oxidative stress in a variety of disorders and several biological models.

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The Purkinje cells of the cerebellum provide inhibitory input to vestibular nucleus neurons, with gamma-aminobutyrate (GABA) as neurotransmitter. Using extracellular recordings and bath application of agonists and antagonists, we compared GABA receptors in the medial vestibular nucleus of brain slices from Scn8a mutant mice of med(J) type, in which there is greatly reduced spontaneous and evoked activity of Purkinje cells, to those in slices from control mice. Muscimol, an agonist at GABA(A) receptors, produced a larger reduction of firing rate in neurons of mutant mice than in neurons of control mice, whereas there was no difference for baclofen, an agonist at GABA(B) receptors.

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