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A modified 3D re-entrant honeycomb is designed and fabricated utilizing Laser Cladding Deposition (LCD) technology, the mechanical properties of which are systematically investigated by experimental and finite element (FE) methods. Firstly, the influences of honeycomb angle on localized deformation and the response of force are studied by an experiment. Experimental results reveal that the honeycomb angles have a significant effect on deformation and force. Secondly, a series of numerical studies are conducted to analyze stress characteristics and energy absorption under different angles (α) and velocities (v). It is evident that two variables play an important role in stress and energy. Thirdly, response surface methodology (RSM) and the Non-Dominated Sorting Genetic Algorithm II (NSGA-II) are implemented with high precision to solve multi-objective optimization. Finally, the final compromise solution is determined based on the fitness function, with an angle of 49.23° and an impact velocity of 16.40 m/s. Through simulation verification, the errors of energy absorption (EA) and peak crush stress (PCS) are 9.26% and 0.4%, respectively. The findings of this study offer valuable design guidance for selecting the optimal design parameters under the same mass conditions to effectively enhance the performance of the honeycomb.
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To understand the distribution of non-structural carbohydrates (NSC) and adaptive mechanism in the process of drought-induced mortality, two-year-old Pinus sylvestris var. mongolica seedlings were grown under continuous natural drought condition. Needle water potential and the contents of soluble sugar, starch and total NSC in different organs (current-year-old needles, one-year-old needles, stems, coarse roots and fine roots) of the seedlings were measured when soil water content decreased to 60%, 40%, 30%, 20% and 15% of the soil field water capacity (SFC). The results showed that when the soil water content decreased from 40% SFC to 15% SFC, there was no significant change in needle water potential at predawn and midday. When soil water content decreased from 60% SFC to 30% SFC, the contents of soluble sugar, starch, total NSC and the ratio of soluble sugar and starch first decreased and then increased in all organs. When soil water content dropped from 30% SFC to 20% SFC, the soluble sugar, starch and total NSC contents decreased in the current-year-old needles, one-year-old needles, stems and fine roots. The soluble sugar content increased, but the starch and total NSC contents decreased in the coarse roots. When soil water content decreased from 20% SFC to 15% SFC, the contents of soluble sugar, starch and total NSC decreased in the current-year-old needles, one-year-old needles and stems, and the soluble sugar and total NSC contents decreased, but the starch content increased in the coarse roots, the soluble sugar content decreased, but the starch and total NSC contents increased in fine roots. The results indicated that NSC content in different organs of P. sylvestris var. mongolica seedlings varied in their adaptation to different degrees of drought. The contents of soluble sugar and total NSC in seedlings decreased under less than 30% of the soil field water capacity, with the starch being accumulated in the coarse roots and fine roots. The seedlings might be died due to carbon depletion.
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Carboidratos/análise , Secas , Pinus sylvestris/fisiologia , Raízes de Plantas , PlântulaRESUMO
BACKGROUND: Mycoplasmal pneumonia is a common type of adult community-acquired pneumonia in China, but round/spherical pneumonia caused by mycoplasma pneumoniae has rarely been reported. Here, we report an outbreak of mycoplasmal round pneumonia in a military dormitory in China. METHODS: We analysed epidemiological, clinical, imaging and laboratory data from a series of adults affected by an outbreak of mycoplasmal round pneumonia in the dormitory of a military hospital (Fuzhou General Hospital) in Fuzhou, China. The dormitory included 2 separate buildings. Mycoplasma antibody was detected using a passive agglutination assay. RESULTS: The first case in our series, a 23-year-old male intern, presented on July 16, 2015 with a 3-day history of low-grade fever, dizziness, fatigue and chest tightness. Chest computed tomography revealed spherical masses. Over the following 4 days, 11 individuals who had been in close contact with the first patient were found to have similar masses. All 12 cases were mildly symptomatic or asymptomatic, and fever was the only sign visible upon physical examination. Chest radiology revealed single, round consolidations in 3 cases and multiple round consolidations in 9 cases; consolidations ranged in size from 0.2 to 2.9 cm. Most cases had normal blood cell count, erythrocyte sedimentation rate and C reactive protein level. Nasopharyngeal swabs from all cases tested negative for 25 pathogens, including Mycoplasma pneumoniae, in a PCR-based assay performed on August 1, 2015. All 12 patients showed a 4-fold increase in the titre of anti-mycoplasmal pneumonia antibody in paired sera on August 13, 2015. Patients were given the antibiotic moxifloxacin or symptomatic treatment, and 11 of the 12 cases showed complete resolution of round pneumonia lesions within 4 weeks. CONCLUSION: This case series illustrates the diversity of clinical manifestations as well as imaging findings for mycoplasmal pneumonia, to which clinicians should pay more attention. Mycoplasmal round pneumonia should be included in differential diagnosis of multiple pulmonary nodules in adults in order to enable accurate clinical identification of disease and successful treatment and resolution.
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Infecções Comunitárias Adquiridas/epidemiologia , Moxifloxacina/uso terapêutico , Mycoplasma pneumoniae/imunologia , Pneumonia por Mycoplasma/epidemiologia , Testes de Aglutinação , Antibacterianos/uso terapêutico , China/epidemiologia , Infecções Comunitárias Adquiridas/diagnóstico , Infecções Comunitárias Adquiridas/tratamento farmacológico , Diagnóstico Diferencial , Surtos de Doenças , Humanos , Masculino , Moxifloxacina/administração & dosagem , Mycoplasma pneumoniae/genética , Pneumonia por Mycoplasma/diagnóstico por imagem , Pneumonia por Mycoplasma/tratamento farmacológico , Tomografia Computadorizada por Raios X , Resultado do Tratamento , Adulto JovemRESUMO
To understand the effects of precipitation increase and nitrogen addition on non-structural carbohydrates (NSC) of poplar seedlings, Populus × xiaozhuanica cv. Zhangwu seedlings were grown under a full factorial experimental design of two factors, i.e., three water treatments (W1,natural precipitation; W2, natural precipitation increased by 50%; W3, increased by 100%) and four N fertilization levels (N1,0 g N·m-2·a-1; N2,5 g N·m-2·a-1; N3,10 g N·m-2·a-1; N4,15 g N·m-2·a-1). The results showed that changes in NSC contents in each organ of P. Zhangwu seedlings reflected significant interactions between precipitation increase and nitrogen addition. With the increase of precipitation, under the N1 level, soluble sugar content was unchanged in leaves and branches, while the starch content decreased in leaves, branches, stems, coarse and fine roots. With the increase of precipitation, the soluble sugar content remained unchanged or declined, while the starch content decreased or firstly increased and then decreased in different organs under the N2 and N3 levels. The soluble sugar and starch contents increased or firstly decreased and then increased in different organs under the N4 level. With the increase of N addition, the soluble sugar content remained unchanged and the starch content increased in leaves, soluble sugar content increased and starch content was unchanged in fine roots in the W1 treatment. The soluble sugar content remained unchanged or firstly increased and then decreased, and the starch content decreased or firstly increased and then decreased in different organs in the W2 treatment. The soluble sugar, starch and NSC contents increased in the W3 treatment. In different precipitation and N addition treatments, the soluble sugar contents of P. Zhangwu seedlings ranged from 39.1 to 88.3 mg·g-1, with the highest value observed in leaves and the lowest value in fine roots, and the starch content ranged from 23.3 to 46.8 mg·g-1, with the highest in coarse roots and the lowest in fine roots.
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Carboidratos , Populus , Plântula , Nitrogênio , Folhas de Planta , Raízes de PlantasRESUMO
BACKGROUND/AIMS: The main purpose of the present study was to determine the effect of peritoneal charge barrier dysfunction on hypoalbuminemia during CAPD. METHODS: We measured the association of dialysis dose, peritoneal equilibration test (PET) results (ratio of dialysate and plasma creatinine), and peritoneal charge barrier index (ratio of pancreatic and salivary α-amylase clearance) on protein loss in 33 patients on maintenance CAPD. All patients were from a single institution and were diagnosed with chronic nephritis (n = 18 cases), diabetic nephropathy (n = 8), hypertension (n = 5), and hepatitis B virus-associated glomerulonephritis (n = 2). RESULTS: The mean (± SD) dialysate protein loss was 4.04 g (± 1.97) per day. Protein loss was positively correlated with dialysis dose (r = 0.438, p = 0.01) but was not significantly correlated with PET results. The mean (± SD) peritoneal charge barrier index was 6.12 (± 21.20) and was inversely correlated with protein loss into the peritoneal dialysate (r = -0.532, p < 0.01). CONCLUSIONS: Taken together, our study of CAPD patients indicates that protein loss into the peritoneal dialysate increases with peritoneal dialysis dose and with disruption of the peritoneal charge barrier. © 2013 S. Karger AG, Basel.
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Creatinina/sangue , Soluções para Diálise/administração & dosagem , Soluções para Diálise/efeitos adversos , Hipoalbuminemia/sangue , Hipoalbuminemia/diagnóstico , Diálise Peritoneal Ambulatorial Contínua/efeitos adversos , Adulto , Idoso , Idoso de 80 Anos ou mais , Biomarcadores/sangue , Feminino , Humanos , Masculino , Pessoa de Meia-Idade , Adulto JovemRESUMO
BACKGROUND: The plasma concentration of very low density lipoprotein (VLDL) is negatively correlated to renal function in glomerular diseases. Effects of VLDL on renal function have been partially attributed to the proliferation of mesangial cells. This study examined the potential role of the p42/44 mitogen activated protein kinase (MAPK) in mesangial cell proliferation induced by VLDL. METHODS: Mesangial cells were treated with VLDL at different concentrations or for different time. The cell cycle of the mesangial cells was analyzed by XTT assay and flow-cytometry; MAPK activity was also assayed. In some experiments, cells were treated with VLDL together with or without 0.1 µmol/L PD 98059. RESULTS: Ten to 500 µg/ml VLDL stimulated the proliferation of mesangial cells cultured in vitro in a concentration-dependent manner. The effect was associated with an increase in p42/44 MAPK activity. Increased proliferation of mesangial cells by VLDL was significantly attenuated by PD98059, a specific p42/44 MAPK inhibitor. CONCLUSION: These results indicate that the p42/44 MAPK pathway is an important regulator of mesangial cell proliferation and of renal functions.