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1.
Opt Express ; 31(23): 37597-37603, 2023 Nov 06.
Artigo em Inglês | MEDLINE | ID: mdl-38017886

RESUMO

A high power single-frequency operation at 1112 nm with novel insertable monolithic planar ring oscillator based on a Nd:YAG/YAG bonded crystal is proposed. In a proof-of-principle experiment, a finely designed coating on the output surface is carried out to ensure single-wavelength oscillation at 1112 nm, together with a half-wave plate and a Tb3Ga5O12 crystal inserted in the open space of the bonded block to realize the unidirectional operation with power scalability. Consequently, the single-frequency laser delivers an output power of 3.9 W at 1112.3 nm with a slope efficiency of 58.6% and an optical-to-optical efficiency of 17.7%. The power fluctuation is measured to be within ± 0.26% over 20 min, and the laser linewidth is estimated to be 4.15 MHz (Δλ = 0.017 pm).

2.
Appl Opt ; 61(19): 5614-5618, 2022 Jul 01.
Artigo em Inglês | MEDLINE | ID: mdl-36255789

RESUMO

A compact 200 W level diode-side-pumped microsecond (µs) pulse linearly polarized rod Nd:YAG laser oscillator was demonstrated with nearly diffraction-limited beam quality. The oscillator was based on a thermally near-unstable cavity design with two concave lenses in the cavity to enlarge the volume of the fundamental mode, leading to improvement of the laser efficiency and beam quality. Consequently, a record-high average power of 222 W was obtained at a repetition rate of 400 Hz with a 180 µs pulse width, corresponding to an optical-to-optical (o-o) conversion efficiency of 37%. The average beam quality factor was measured to be M2=1.32, resulting in a brightness value as high as of 11.25GW/sr⋅cm2. To the best of our knowledge, this represented the highest average power, the highest o-o efficiency, and the highest brightness for a µs pulse 1064 nm rod Nd:YAG laser oscillator.

3.
Chemosphere ; 244: 125582, 2020 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-32050352

RESUMO

As the most typical geological environment, limestone landforms are widespreading in the world and affect the waters that flow around them, which may also change the fate of organic contaminants in these waters. In this study, aquatic environment surrounding limestone was simulated with calcium carbonate, and the photolysis of tetracycline was evaluated under UV irradiation (30 µW/cm2). More tetracycline (up to 98%) was removed in 4 h in the presence of calcium carbonate while only 50% of tetracycline was eliminated in control experiment. The removal of tetracycline was greatly enhanced due to the major roles of alkaline pH and minor roles of Ca2+ and HCO3-/CO32-. In alkaline pH, tetracycline existed as TCs- with higher electronic density in the ring structures, which was more easily attacked by OH. Besides, it could also change the bond orbital energy to facilitate tetracycline absorbing more photon. Moreover, alkaline pH was beneficial to generate more OH and thus promote the indirect photolysis. In addition, alkaline pH also changed the degradation path of tetracycline and rapidly convert tetracycline to the byproducts with m/z 457 via hydroxylation and hydrogen abstraction. This work provides not only better understanding about the fate of tetracycline in aquatic environments but also new insights into the treatment of antibiotic-contaminated water.


Assuntos
Poluentes Químicos da Água/química , Antibacterianos , Carbonato de Cálcio , Cinética , Fotólise , Tetraciclina/análise , Tetraciclina/química , Raios Ultravioleta , Poluentes Químicos da Água/análise
4.
Sci Total Environ ; 706: 136086, 2020 Mar 01.
Artigo em Inglês | MEDLINE | ID: mdl-31855650

RESUMO

Recently, biochar is widely used as a soil amendment to improve soil properties, which might affect the fate and behavior of contaminants in soil. In this study, we investigated the effect of biochar on the migration of tetracycline (TC) in soil and their combined impacts on microbiome. Due to the strong interaction between soil and TC, adsorption, rather than photolysis or biodegradation, was the dominating dissipation way of TC in soil. Moreover, biochar could promote the vertical migration of TC through the decreased soil bulk density and its lower adsorption capacity. After 90-day incubation, only slight impact of TC on soil bacterial community was observed due to the rapid dissipation of TC in soil, whereas more available C supply induced by biochar significantly altered bacterial community via the enhancement of copiotrophic bacteria. Besides, biochar could decrease the soil pH and thus change the composition of fungal community. The effect of TC on fungal community was partially counteracted by biochar, which could adsorb part of TC and thus decrease the contact of TC with microorganisms. This work will improve our understanding of the fate of organic pollutants and evolution of microbiome in soil where biochar servers as soil amendment.


Assuntos
Carvão Vegetal , Microbiota , Agricultura , Solo , Microbiologia do Solo , Poluentes do Solo
5.
Artigo em Inglês | MEDLINE | ID: mdl-30800168

RESUMO

Dysfunction of insulin secretion and hyperglycaemia were commonly found due to damaged ß cells of pancreas. In our previous research, it was found that mulberry branch bark powder (MBBP) was effective in treating diabetes in mice which were induced by STZ and high fat diet. The present study was designed to evaluate the protective effect of MBBP on STZ-induced ß cells injury and investigate underlying mechanisms. By preventive administration of branch bark powder, the damage caused by STZ injection was found to be alleviated. In MBBP feed groups, pathological weight loss was inhibited, fasting blood glucose was controlled, the incidence of diabetes decreased, and blood lipid level and antioxidant capacities were restored. The PI3K/AKT/FoxO1 signal pathway was found to be activated by key proteins expression and gene testing. In liver, the increased PI3K and phosphorylated AKT, the phosphorylated, and inactivated FoxO1, which regulates the expression of gluconeogenic gene and explains the effect of relieving insulin resistance of MBBP. Therefore, the MBBP improves the tolerance of pancreas to the toxicity of STZ involving the PI3K/AKT/FoxO1 signalling pathway.

6.
Food Nutr Res ; 61(1): 1368847, 2017.
Artigo em Inglês | MEDLINE | ID: mdl-28970780

RESUMO

This experiment, based on the previous study on R. mori, introduces whole mulberry branch powder into the diet to treat diabetic mice. Mulberry branch bark powder (MBBP) was administered orally to streptozotocin (STZ)-induced type II diabetic (T2D) mice to investigate hypoglycemic effects. After a 4-week period of diet consumption containing 5%, 10% and 20% MBBP, the fasting blood glucose, body weight and the related western blotting were measured, pathologic and immunohistochemical were observed. The 20% MBBP group showed a significant reduction in hyperglycemia and hyperinsulinemia; fasting blood glucose and insulin decreased from 25.0 to 14.8 mmol/L and 26.5 to 16.0 mU/L, respectively. Pathologic and immunohistochemical observation showed that MBBP administration lead to the repair of pancreas cells and restoration of insulin secretion. Dietary MBBP was associated with the decrease in the contents of 3, 4-methylenedioxeamphetamine, 8-OHdG, aspartate aminotransferase, and alanine aminotransferase, and the increase in antioxidative ability and glucose tolerance. Western blotting (WB) analysis suggested that MBBP decreased the TNF-α levels, thus relieving inflammation and improving liver function. It also led to the downregulation of apoptosis factor expression. WB also confirmed that MBBP enhanced the gene expression of the key enzymes: insulin receptor, insulin receptor substrate, p-AKT, GSK3ß, glycogen synthase, G6Pase and phosphoenolpyruvate carboxykinase, which are related to glucose metabolism in the liver, and increase the expression of the genes PDX-1, GLUT2, MafA, and glucokinase, related to insulin secretion. Thus, oral administration of MBBP regulated insulin secretion and effectively maintained normal levels of glucose metabolism in mice, which may be done by improving the antioxidant capacity and activating insulin signaling with T2D..

7.
Chin J Traumatol ; 19(4): 199-205, 2016 Aug 01.
Artigo em Inglês | MEDLINE | ID: mdl-27578374

RESUMO

PURPOSE: To enhance the awareness of rare complications of pelvic fracture and describe the correct diagnosis and effective treatment. METHODS: A total of 188 cases of pelvic fractures were retrospectively reviewed, and four patients who suffered from four types of rare pelvic fracture complications were described, namely ureteral obstruction caused by retroperitoneal hematoma-induced abdominal compartment syndrome (ACS), bowel entrapment, external iliac artery injury, and open scrotal sac injury. RESULTS: We demonstrated that combined measures should be employed to prevent the occurrence of ACS following major pelvic fractures. Ureteral catheter support may be a good option at an early stage when ACS occurred. Contrasted computed tomography examination and sufficient awareness are keys to a correct diagnosis of bowel entrapment following pelvic fractures. Recognition of risk factors, early diagnosis, and prompt treatment of suspected injury of the external iliac artery are keys to patient survival and to avoid limb loss. Scrotal and/or testicular injury complicated by pelvic fractures should be carefully treated to maintain normal gonad function. Additionally, establishment of a sophisticated trauma care system and multi-disciplinary coordination are important for correct diagnosis and treat- ment of rare complications in pelvic fractures. CONCLUSIONS: Rare complications of pelvic fractures are difficult to diagnose and negatively impact outcome. Recognition of risk factors and sufficient awareness are essential for correct diagnosis and prompt treatment.


Assuntos
Fraturas Ósseas/complicações , Hipertensão Intra-Abdominal/diagnóstico , Ossos Pélvicos/lesões , Adulto , Feminino , Humanos , Artéria Ilíaca/lesões , Hipertensão Intra-Abdominal/terapia , Masculino , Pessoa de Meia-Idade , Escroto/lesões , Testículo/lesões , Tomografia Computadorizada por Raios X
8.
Food Nutr Res ; 60: 31606, 2016.
Artigo em Inglês | MEDLINE | ID: mdl-27257845

RESUMO

BACKGROUND: Diabetes is a group of metabolic diseases that has become a global health problem worldwide. Many researchers have found that mulberry branches have a hypoglycemic effect, but there have been few studies or investigations regarding the use of mulberry branches to prevent the incidence of diabetes. OBJECTIVE: This study aimed to investigate the potential preventive effect of mulberry branch bark powder (MBBP) from Morus multicaulis L against type II diabetes in mice induced by streptozotocin (STZ). DESIGN: The normal mice were fed a diet containing 2.5, 5.0, and 10.0%, MBBP, respectively, for 2 weeks. After that, STZ (100 mg/kg) was injected into the caudal vein of these mice. These mice continued to be fed the same diet, and the fasting blood glucose (FBG) levels were monitored on the 17th and 21st days. RESULTS: Oral administration of MBBP could effectively inhibit weight loss and maintain the FBG level. The incidence of diabetes in mice was almost inhibited by treatment with 10% MBBP. MBBP could also maintain the original antioxidant capacity and regulate the lipid metabolism in mice. An immunohistochemical assay showed that MBBP could prevent the injury of the insulin-secreting islet beta cells induced by STZ. RT-PCR also confirmed that the mRNA expression of the genes PI3K, Pdk1, Akt, and FoxO1, which were involved in the PI3K/Akt signaling pathway, hardly suffered from STZ in the 10% MBBP-dose group. CONCLUSIONS: Our results indicate that powdered mulberry branch bark has a powerful anti-diabetic effect. These results clearly illustrated that MBBP has a potential use as a health food additive in the prevention of diabetes.

9.
ScientificWorldJournal ; 2014: 614265, 2014.
Artigo em Inglês | MEDLINE | ID: mdl-25177729

RESUMO

Branch bark extract (BBE) derived from the mulberry cultivar Husang 32 (Morus multicaulis L.) with aqueous alcohol solution has been investigated as an inhibitor of α-glycosidase in vitro. Mulberry BBE was orally administered to STZ-induced diabetic mice for three weeks, and it improved the weight gain and ameliorated the swelling of liver and kidney in diabetic mice. Obviously, mulberry BBE not only can reduce the abnormally elevated levels of serum insulin and ameliorate insulin resistance induced by STZ, but also it regulates dyslipidemia in diabetic mice. To understand this therapeutic effect and the regulatory mechanisms of BBE in diabetic mice, a qRT-PCR experiment was performed, indicating that the mulberry BBE can regulate the mRNA expression of glycometabolism genes in diabetic mice, including glucose-6-phosphatase (G6Pase), glucokinase (GCK), and phosphoenolpyruvate carboxykinase (PEPCK), thereby regulating sugar metabolism and reducing the blood glucose level in diabetic mice. The mulberry BBE can increase the mRNA expression of the genes Ins1, Ins2 and pancreatic duodenal homeobox-1 (PDX-1) and may decrease the insulin resistance in diabetic mice. Those results provide an important basis for making the best use of mulberry branch resources and producing biomedical drugs with added value.


Assuntos
Diabetes Mellitus Experimental/tratamento farmacológico , Medicamentos de Ervas Chinesas/uso terapêutico , Morus/química , Animais , Glicemia/metabolismo , Diabetes Mellitus Experimental/metabolismo , Glucoquinase/genética , Glucoquinase/metabolismo , Glucose-6-Fosfatase/genética , Glucose-6-Fosfatase/metabolismo , Proteínas de Homeodomínio/genética , Proteínas de Homeodomínio/metabolismo , Insulina/genética , Insulina/metabolismo , Resistência à Insulina , Masculino , Camundongos , Camundongos Endogâmicos ICR , Fosfoenolpiruvato Carboxiquinase (ATP)/genética , Fosfoenolpiruvato Carboxiquinase (ATP)/metabolismo , Casca de Planta/química , RNA Mensageiro/genética , RNA Mensageiro/metabolismo , Transativadores/genética , Transativadores/metabolismo
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