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1.
Neurosci Bull ; 2023 Nov 16.
Artículo en Inglés | MEDLINE | ID: mdl-37973720

RESUMEN

Neuroinflammation mediated by microglia and oxidative stress play pivotal roles in the development of chronic temporal lobe epilepsy (TLE). We postulated that kainic acid (KA)-Induced status epilepticus triggers microglia-dependent inflammation, leading to neuronal damage, a lowered seizure threshold, and the emergence of spontaneous recurrent seizures (SRS). Extensive evidence from our laboratory suggests that dextromethorphan (DM), even in ultra-low doses, has anti-inflammatory and neuroprotective effects in many animal models of neurodegenerative disease. Our results showed that administration of DM (10 ng/kg per day; subcutaneously via osmotic minipump for 4 weeks) significantly mitigated the residual effects of KA, including the frequency of SRS and seizure susceptibility. In addition, DM-treated rats showed improved cognitive function and reduced hippocampal neuronal loss. We found suppressed microglial activation-mediated neuroinflammation and decreased expression of hippocampal gp91phox and p47phox proteins in KA-induced chronic TLE rats. Notably, even after discontinuation of DM treatment, ultra-low doses of DM continued to confer long-term anti-seizure and neuroprotective effects, which were attributed to the inhibition of microglial NADPH oxidase 2 as revealed by mechanistic studies.

2.
Sensors (Basel) ; 23(16)2023 Aug 08.
Artículo en Inglés | MEDLINE | ID: mdl-37631572

RESUMEN

The application of mulching film has significantly contributed to improving agricultural output and benefits, but residual film has caused severe impacts on agricultural production and the environment. In order to realize the accurate recycling of agricultural residual film, the detection of residual film is the first problem to be solved. The difference in color and texture between residual film and bare soil is not obvious, and residual film is of various sizes and morphologies. To solve these problems, the paper proposes a method for detecting residual film in agricultural fields that uses the attention mechanism. First, a two-stage pre-training approach with strengthened memory is proposed to enable the model to better understand the residual film features with limited data. Second, a multi-scale feature fusion module with adaptive weights is proposed to enhance the recognition of small targets of residual film by using attention. Finally, an inter-feature cross-attention mechanism that can realize full interaction between shallow and deep feature information to reduce the useless noise extracted from residual film images is designed. The experimental results on a self-made residual film dataset show that the improved model improves precision, recall, and mAP by 5.39%, 2.02%, and 3.95%, respectively, compared with the original model, and it also outperforms other recent detection models. The method provides strong technical support for accurately identifying farmland residual film and has the potential to be applied to mechanical equipment for the recycling of residual film.

3.
Int J Biol Macromol ; 251: 126257, 2023 Aug 12.
Artículo en Inglés | MEDLINE | ID: mdl-37573900

RESUMEN

Mentha spicata L. is a valuable plant that yields spearmint oil, widely utilized in the pharmaceutical, chemical, and cosmetic industries. The mitochondrial genome (mitogenome) is an essential material for molecular breeding and evolution studies. Here, the mitogenome of M. spicata was assembled by combining Nanopore and Illumina reads. It consisted of a linear chromosome (Ch1) and two circular chromosomes (Ch2 and Ch3). Furthermore, we showed two pairs of repeats (R1 and R2) mediated recombinations resulting in multiple chromosomal configurations. The R1-mediated-recombination generated a large molecule formed by joining Ch2 and Ch1. Similarly, the R2-mediated-recombination generated a large molecule formed by joining Ch3 and Ch1. Then, we identified 17 mitochondrial plastid DNAs (MTPTs) by comparing the mitogenome and cpgenome. The MTPT14 was conserved in multiple species, which has undergone the same evolutionary process as the two organellar genomes among M. spicata, Hesperelaea palmeri and Castilleja paramensis. Based on the RNA-seq reads, 246 RNA editing sites were predicted, resulting in the conversion of cytosine to uracil bases. Furthermore, we successfully validated 40 out of 43 predicted sites. This project reported a complex structure of the M. spicata mitogenome resulting from repeat-mediated recombinations, which will provide valuable information for gene function study and the breeding of different varieties.

4.
Nanomaterials (Basel) ; 11(8)2021 Jul 30.
Artículo en Inglés | MEDLINE | ID: mdl-34443795

RESUMEN

Mechanical anisotropy and point defects would greatly affect the product quality while producing silicon wafers via diamond-wire cutting. For three major orientations concerned in wafer production, their mechanical performances under the nanoscale effects of a point defect were systematically investigated through molecular dynamics methods. The results indicated anisotropic mechanical performance with fracture phenomena in the uniaxial deformation process of monocrystalline silicon. Exponential reduction caused by the point defect has been demonstrated for some properties like yield strength and elastic strain energy release. Dislocation analysis suggested that the slip of dislocations appeared and created hexagonal diamond structures with stacking faults in the [100] orientation. Meanwhile, no dislocation was observed in [110] and [111] orientations. Visualization of atomic stress proved that the extreme stress regions of the simulation models exhibited different geometric and numerical characteristics due to the mechanical anisotropy. Moreover, the regional evolution of stress concentration and crystal fracture were interrelated and mutually promoted. This article contributes to the research towards the mechanical and fracture anisotropy of monocrystalline silicon.

5.
Nat Commun ; 11(1): 1402, 2020 Mar 16.
Artículo en Inglés | MEDLINE | ID: mdl-32179750

RESUMEN

Amongst the rare-earth perovskite nickelates, LaNiO3 (LNO) is an exception. While the former have insulating and antiferromagnetic ground states, LNO remains metallic and non-magnetic down to the lowest temperatures. It is believed that LNO is a strange metal, on the verge of an antiferromagnetic instability. Our work suggests that LNO is a quantum critical metal, close to an antiferromagnetic quantum critical point (QCP). The QCP behavior in LNO is manifested in epitaxial thin films with unprecedented high purities. We find that the temperature and magnetic field dependences of the resistivity of LNO at low temperatures are consistent with scatterings of charge carriers from weak disorder and quantum fluctuations of an antiferromagnetic nature. Furthermore, we find that the introduction of a small concentration of magnetic impurities qualitatively changes the magnetotransport properties of LNO, resembling that found in some heavy-fermion Kondo lattice systems in the vicinity of an antiferromagnetic QCP.

6.
Opt Lett ; 42(18): 3658-3661, 2017 Sep 15.
Artículo en Inglés | MEDLINE | ID: mdl-28914926

RESUMEN

A new record for high-finesse silica waveguide ring resonators (WRRs), to the best of our knowledge, is demonstrated experimentally. The achieved finesse and resonant depths of the silica WRR with a length of 7.9 cm and a diameter of 2.5 cm are 196.7% and 98%, respectively. In addition, the silica WRR chip is coupled with single-polarization fiber to improve the polarization extinction ratio (PER) and, thus, to reduce the polarization error. With the application of this high-finesse and high-PER WRR to the resonant micro-optic gyroscope (RMOG), a bias stability of 0.004°/s is observed over a 1 h timeframe. To the best of our knowledge, this is the first RMOG reported in the open literature that can sense the earth's rotation rate (15°/h).

7.
Exp Ther Med ; 13(2): 495-502, 2017 Feb.
Artículo en Inglés | MEDLINE | ID: mdl-28352321

RESUMEN

Inflammation is implicated in the pathogenesis of diabetic nephropathy (DN). Toll-like receptor 2 (TLR2) is a ligand-activated membrane-bound receptor, which induces an inflammatory response, thus serving a crucial role in the pathogenesis of DN. The present study aimed to determine whether a TLR2 agonist, Pam3CysSK4, modulates the development of DN. A mouse model of DN was induced using streptozotocin (STZ) and, following the confirmation of hyperglycemia, mice were treated with or without Pam3CysSK4. Pathological and functional markers, including the activation of nuclear factor (NF)-κB, expression of TLR2, inflammatory infiltration, myeloid differentiation primary response gene 88 and monocyte chemoattractant protein-1 were assessed. STZ-treated mice exhibited elevated blood glucose levels and increased serum creatinine levels, which increased further following Pam3CysSK4 treatment. In addition, Pam3CysSK4 treatment was observed to increase podocyte foot process formation. Furthermore, STZ-induced renal glomerular sclerosis was significantly exacerbated in Pam3CysSK4-treated mice. Pam3CysSK4-treated mice also exhibited increased levels of collagen IV following renal immunostaining, associated with increased macrophage infiltration. Renal expression of TLR2 was markedly elevated in STZ-induced mice; this was further increased in Pam3CysSK4-treated mice, accompanied by upregulation of proinflammatory genes and activation of NF-κB. This indicates that enhanced renal expression of TLR2 is associated with inflammatory infiltration in DN and demonstrates that renal injury was exacerbated by the TLR2 agonist in diabetic mice.

8.
Appl Opt ; 55(32): 9329-9333, 2016 Nov 10.
Artículo en Inglés | MEDLINE | ID: mdl-27857328

RESUMEN

A fiber ring resonator is the key element in a resonant fiber optic gyroscope (RFOG). Both reflection and loss characteristics can severely decrease the accuracy of the RFOG. This paper first implements optical frequency domain reflectometry (OFDR) to measure the reflection and loss coefficients of the hybrid air-core photonic-bandgap fiber (PBF) ring resonator. Compared with the traditional measurement method of the resonant curve, OFDR can clearly distinguish the two junctions between the air-core PBF and the solid-core fiber. The measured reflection coefficients at the two splicing points are 1.77% and 2.65%, respectively. The excess losses are 2.28 dB and 3.22 dB, respectively. Thus, the measurement of the junctions in the fiber ring resonator is realized.

9.
Ying Yong Sheng Tai Xue Bao ; 27(1): 207-14, 2016 Jan.
Artículo en Chino | MEDLINE | ID: mdl-27228611

RESUMEN

China's livestock and poultry productions have changed significantly in the last three decades, from mainly traditional and small-scale systems in early 1980s towards more intensive and industrialized ones in recent years, due to the booming economy and the changes in people' diet. There is an urgent need to increase the understanding of the changes in the livestock and poultry productions and the impact of manure recycle on the environment. Here, we reported on a systematic and quantitative analysis on the temporal and spatial variability of livestock and poultry productions and manure nutrients in Shanxi Province, China, using a large database and a coupled food chain nutrient flow model (NUFER) with GIS. In the period of 1978 to 2012, total animal manure production increased from 1.61 x 107 t to 2.75 x 107 t by 171%. The manure N increased from 7.74 x 104 t to 17.32 x 104 t, and the manure P from 1.09x104 t to 3.39x104 t. Besides the huge increase in total animal manure production, the distribution of animal manure was much uneven among regions, with high amounts of manure N and P per unit land in the north, middle and southeastern regions and low values in the north-central and southwestern regions, based on the results of 2012. The uneven distribution of manure was the combined effect of regional specializations in livestock and poultry productions and related policies. Our findings suggested that optimizing the structure of livestock and poultry productions and enhancing interregional collaborations on nutrient management could be two effective measures for reducing pollution and environmental risks, while achieving efficient and sustainable use of manure nutrient in the long term.


Asunto(s)
Agricultura , Ganado , Estiércol , Aves de Corral , Análisis Espacio-Temporal , Animales , China , Ambiente , Contaminación Ambiental , Nitrógeno/análisis , Fósforo/análisis
12.
Opt Lett ; 40(24): 5862-5, 2015 Dec 15.
Artículo en Inglés | MEDLINE | ID: mdl-26670531

RESUMEN

A novel hybrid integrated scheme is proposed for a high-performance resonant micro-optic gyro (RMOG), which requires a low-loss micro-ring resonator for mass production. A new record for the RMOG is established experimentally with a short fiber ring resonator and an integrated signal detecting and processing circuit. The finesse of the short fiber ring resonator with a length of 60 cm and a diameter of 4.77 cm is as high as 202, and the theoretical sensitivity of the RMOG is better than 0.3°/h assuming the average optical intensity at the photodetector is 1 mW. The 60 cm long spliceless micro-ring resonator is experimentally proved to be sufficient for a tactical-grade RMOG. An angle random walk coefficient of 0.64°/√h and a typical bias stability below 9.6°/h for the integration time of 50 s are successfully demonstrated using an innovative open-loop approach for an operation time of 1600 s.

13.
Opt Express ; 23(12): 15088-97, 2015 Jun 15.
Artículo en Inglés | MEDLINE | ID: mdl-26193493

RESUMEN

It is well-known that the closed-loop operation in optical gyros offers wider dynamic range and better linearity. By adding a stair-like digital serrodyne wave to a phase modulator can be used as a frequency shifter. The width of one stair in this stair-like digital serrodyne wave should be set equal to the optical transmission time in the resonator, which is relaxed in the hybrid digital phase modulation (HDPM) scheme. The physical mechanism for this relaxation is firstly indicated in this paper. Detailed theoretical and experimental investigations are presented for the HDPM. Simulation and experimental results show that the width of one stair is not restricted by the optical transmission time, however, it should be optimized according to the rise time of the output of the digital-to-analogue converter. Based on the optimum parameters of the HDPM, a bias stability of 0.05°/s for the integration time of 400 seconds in 1 h has been carried out in an RMOG with a waveguide ring resonator with a length of 7.9 cm and a diameter of 2.5 cm.

14.
Artículo en Chino | MEDLINE | ID: mdl-25916453

RESUMEN

OBJECTIVE: To investigate the significance of monitoring procalcitonin (PCT) when applying antibiotics to trichlorethylene (TCE)-induced dermatitis. METHODS: One hundred and two patients who were hospitalized and recovered from TCE-induced dermatitis in our hospital from 2006 to 2013 were enrolled as subjects. Based on whether the PCT level was monitored or not, we divided patients into regular group and PCT group. For the regular group, we applied antibiotic treatment and determined the course of treatment based on clinical symptoms, laboratory test results, medical imaging results, and bacterial culture. For the PCT group, in addition to the above treatments, antibiotic treatment was applied when the PCT level was not lower than 0.25 ng/ml and stopped when the PCT level was lower than 0.25 ng/ml. The distribution of bacterial infection sites, type of bacteria, type of antibiotics, average period of hospitalization, and course of antibiotic treatment were compared between the two groups. RESULTS: There were no significant differences in the distribution of bacterial infection sites, type of bacteria, type of antibiotics, and average period of hospitalization between the two groups (P > 0.05). The course of antibiotic treatment for the PCT group was significantly shorter than that for the regular group (25.37 ± 11.66 vs 20.58 ± 7.53 d, P < 0.05). CONCLUSION: Under similar conditions of bacterial infection, antibiotic treatment of TCE-induced dermatitis based on the serum PCT level can significantly shorten the course of treatment and avoid the abuse of antibiotics.


Asunto(s)
Antibacterianos/uso terapéutico , Calcitonina/análisis , Erupciones por Medicamentos/tratamiento farmacológico , Monitoreo Fisiológico , Precursores de Proteínas/análisis , Tricloroetileno/toxicidad , Bacterias , Infecciones Bacterianas , Péptido Relacionado con Gen de Calcitonina , Hospitalización , Humanos
15.
Ying Yong Sheng Tai Xue Bao ; 25(4): 955-60, 2014 Apr.
Artículo en Chino | MEDLINE | ID: mdl-25011285

RESUMEN

The soil organic carbon (SOC) and total nitrogen (TN) storage under five different land use patterns, i. e. , poplar and Caragana microphylla plantation, C. microphylla artificial shrubland, poplar plantation, bare land and cropland were studied in the hilly [ness Plateau of northwestern Shanxi. The results showed that the contents, densities and storage of SOC and TN varied remarkably under the different land-use patterns. Soil carbon and nitrogen contents and storage in the 0-20 cm soil layer were significantly higher in the 20-40 cm and 40-60 cm soil layers under each of the five land use patterns. In the same soil layer, the contents and densities of SOC and TN under the five land use patterns were in the order of poplar and C. microphylla plantation > C. microphylla artificial shrubland > poplar plantation > bare land > cropland. The SOC storage in the 0-60 cm soil layer was in the order of poplar and C. microphylla plantation (30.09 t x hm(-2)) > C. microphylla artificial shrubland (24.78 t x hm(-2)) > poplar plantation (24.14 t x hm(-2)) > bare land (22.06 t x hm(-2)) > cropland (17.59 t x hm(-2)). Soil TN storage had the same trend as SOC storage, and TN storage in the 0-60 cm soil layer was the highest (4.94 t x hm(-2)) in poplar and Caragana microphylla plantation, followed by C. microphylla artificial shrubland (3.53 t x hm(-2)), poplar plantation (3.51 t x hm(-2)), bare land (3.40 t x hm(-2)), and cropland (2.71 t x hm(-2)). Poplar and C. microphylla plantation and C. microphylla artificial shrubland were the good land use patterns in the process of vegetation construction and ecological restoration in the hilly Loess Plateau of northwestern Shanxi.


Asunto(s)
Carbono/análisis , Nitrógeno/análisis , Suelo/química , China , Restauración y Remediación Ambiental , Fabaceae , Bosques , Populus
16.
Artículo en Chino | MEDLINE | ID: mdl-25608901

RESUMEN

OBJECTIVE: To analyze the cause of misdiagnosis of occupational chronic n-hexane poisoning and to investigate the diagnosis and differential diagnosis of this disease. METHODS: The clinical data of 16 patients with occupational chronic n-hexane poisoning who had been misdiagnosed with other diseases were collected. The hospital they first visited, cause of misdiagnosis, clinical features, and the misdiagnosis rate among inpatients during the same period were retrospectively analyzed. RESULTS: Sixteen of 62 patients hospitalized during the same period were misdiagnosed at the first visit; 11 cases were in the upper first-class hospitals, and 5 cases in the upper second-class hospitals; 5 cases were misdiagnosed as Green Barry syndrome, 2 cases as motor neuron disease, 2 cases as drug-induced peripheral neuropathy, 3 cases as periodic paralysis, and 4 cases had uncertain diagnosis. CONCLUSION: Most doctors who work in ordinary hospitals do not know occupational chronic n-hexane poisoning, which is often misdiagnosed as general neuropathies or difficult diseases. The key to correct diagnosis is to know the patient's occupational history and clinical features.


Asunto(s)
Errores Diagnósticos , Hexanos/envenenamiento , Enfermedad Crónica , Diagnóstico Diferencial , Hospitales , Humanos , Enfermedades del Sistema Nervioso Periférico/inducido químicamente , Estudios Retrospectivos
17.
Artículo en Chino | MEDLINE | ID: mdl-24053959

RESUMEN

OBJECTIVE: To investigate and analyze the social support for inpatients with occupational diseases and to provide reference and basis for relevant medical and nursing interventions. METHODS: The social support rating scale (SSRS) was used to investigate the social support for 95 inpatients with occupational diseases. RESULTS: The total SSRS score of these patients was significantly lower than the national norm (32.5±9.31 vs 34.56±3.73, P < 0.05). The social support was mainly from the family, but medical staff and spiritual support were the main source and type of social support that are expected. CONCLUSION: Patients with occupational diseases have gained little social support, in both economic and spiritual aspects. In clinical practice, the patient's demand for knowledge of diseases and spiritual needs should be satisfied, and appropriate social support should be provided.


Asunto(s)
Enfermedades Profesionales , Apoyo Social , Adulto , Femenino , Humanos , Pacientes Internos , Masculino , Encuestas y Cuestionarios , Adulto Joven
19.
Artículo en Chino | MEDLINE | ID: mdl-22804985

RESUMEN

OBJECTIVE: To study the sympathetic skin response (SSR) to the effects of N-hexane on autonomic nerves function in patients with chronic N-hexane poisoning. METHODS: The subjects in present study included 30 controls and 37 cases with chronic N-hexane poisoning. Also 37 patients were divided into 3 subgroups (mild, moderate and severe poisoning) according to diagnostic criteria of occupational diseases. All subjects were examined by SSR test and nerve conduction velocity (NCV) test. All patients were reexamined by SSR and NCV every 1 ∼ 2 months. The differences in SSR parameters (latency, amplitude) among groups were observed. In the severe poisoning subgroup, the changes of SSR and NCV parameters (conduction velocity, amplitude) in different poisoning stages were observed. RESULTS: There were significant differences in SSR latency of upper extremity among groups and the significant differences in SSR amplitude of upper and lower extremity among groups (P < 0.05). No significant differences in SSR parameters were found between the adjacent groups (P > 0.05). There were significant differences in SSR latency of upper extremity during different periods and the significant differences in SSR amplitude of upper and lower extremity during different periods among all groups (P < 0.05). The change of SSR parameters consistent with that in NCV. The longest SSR latency of upper extremity and the smallest SSR amplitudes of upper and lower extremity appears 1 - 2 months earlier than that of the smallest action potential amplitude. CONCLUSION: The damage of autonomic nerves induced by N-hexane increased with poisoning progresses. The damage of autonomic nerves corresponded with the damage of myelin sheath of large myelinated nerves, but which appeared 1 - 2 months earlier than the damage of axon of large myelinated nerves. SSR test may serve as a method to detect the damage of autonomic nerves function in patients with chronic N-hexane poisoning.


Asunto(s)
Hexanos/envenenamiento , Conducción Nerviosa , Enfermedades Profesionales/fisiopatología , Sistema Nervioso Simpático/fisiopatología , Adolescente , Adulto , Vías Autónomas/fisiopatología , Estudios de Casos y Controles , Femenino , Respuesta Galvánica de la Piel , Humanos , Masculino , Piel/inervación , Piel/fisiopatología , Adulto Joven
20.
Artículo en Chino | MEDLINE | ID: mdl-22730693

RESUMEN

OBJECTIVE: To study the better efficacy of clinic treatment for dermatitis medicamentosa like of trichloroethylene (DMLT) and observe the clinic efficacy of Xuebejing injection for DMLT patients with systemic inflammatory response syndrome (SIRS). METHODS: 16 DMLT patients with SIRS were randomly divided into control group (conventional therapy) and xuebijing group (conventional therapy plus xuebijing). We evaluated all the patients with APACHE II before treatment and checked the TNF-alpha in blood at the different time (before treatment and the 7th day of treatment). The total usages, first dosage of medrol and the time of therapy for each group were counted. RESULTS: All patients were cured, there was no significant difference according to APACHE II and TNF-alpha before treatment in two groups . The level of TNF-alpha of all the patients were decreased markedly, but more significantly in xuebijing group (P < 0.01). Moreover, the treatment group patients were given relatively less total usages, first dosage of medrol and time of therapy (P < 0.01). CONCLUSION: Xuebejing injection combined glucocorticoids can cure DMLT patients with SIRS effectively, and reduce the total usages, first dosage of medrol and time of therapy.


Asunto(s)
Erupciones por Medicamentos/tratamiento farmacológico , Medicamentos Herbarios Chinos/uso terapéutico , Glucocorticoides/uso terapéutico , Tricloroetileno/toxicidad , APACHE , Adolescente , Adulto , Quimioterapia Combinada , Femenino , Humanos , Masculino , Factor de Necrosis Tumoral alfa/sangre , Adulto Joven
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