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Motivated by communication networks, we study a single-server queue with varying service rates and multiple customers' types. The difference between types of customers is defined by the profits contributed to the system. We show that the optimal trunk reservation policy exists and we compare the optimal control levels with different parameter values. Furthermore, when the optimal trunk reservation policy is more than one, we prove the uniqueness of the bias optimal policy. [ABSTRACT FROM AUTHOR]

Background: To observe the effects of chalazion and its treatments on meibomian gland function and morphology in the chalazion area.Methods: This nonrandomized, prospective observational clinical study included 58 patients (67 eyelids) who were cured of chalazion, including 23 patients (23 eyelids) treated with a conservative method and 35 patients (44 eyelids) treated with surgery. Infrared meibomian gland photography combined with image analysis by ImageJ software was used to measure the chalazion area proportion. Slit-lamp microscopy was employed to evaluate meibomian gland function, and a confocal microscope was used to observe meibomian gland acinar morphology before treatment and 1 month after complete chalazion resolution.Results: At 1 month after chalazion resolution, the original chalazion area showed meibomian gland loss according to infrared meibomian gland photography in both groups. In patients who received conservative treatment, the meibomian gland function parameters before treatment were 0.74 ± 0.75, 0.48 ± 0.67, and 1.22 ± 0.60, respectively. One month after chalazion resolution, the parameters were 0.35 ± 0.49, 0.17 ± 0.49, and 0.91 ± 0.60, respectively; there was significant difference (P < 0.05). The proportion of the chalazion area before treatment was 14.90 (11.03, 25.3), and the proportion of meibomian gland loss at 1 month after chalazion resolution was 14.64 (10.33, 25.77); there was no significant difference (P > 0.05). In patients who underwent surgery, the meibomian gland function parameters before surgery were 0.93 ± 0.87, 1.07 ± 0.70, and 1.59 ± 0.76, respectively, and at 1 month after chalazion resolution, they were 0.93 ± 0.82, 0.95 ± 0.75, and 1.52 ± 0.70, respectively; there was no significant difference (P > 0.05). The proportion of the chalazion area before surgery was 14.90 (12.04, 21.6), and the proportion of meibomian gland loss at 1 month after chalazion resolution was 14.84 (11.31, 21.81); there was no significant difference (P > 0.05). The acinar structure could not be observed clearly in the meibomian gland loss area in most patients.Conclusions: Chalazion causes meibomian gland loss, and the range of meibomian gland loss is not related to the treatment method but to the range of chalazion itself. A hot compress as part of conservative treatment can improve meibomian gland function at the site of chalazion in the short term. [ABSTRACT FROM AUTHOR]

In this paper, 1-mm-thickness monomer cast nylon 6 sheets were joined under the pressure and the frictional heat generated between the pinless tool and thin stainless steel plates, which was named friction spot pressure welding technology. Influences of welding parameters on spot weld diameter, morphology, and mechanical performance were investigated. Results showed that incomplete interfacial bonding was observed under insufficient plunge depth. Increased rotational speed, plunge depth, and dwell time caused severer extrusion ring and reticular cracks on the joint surface. Material overheating occurred under rotational speed of 1000 rpm and material adhesion on the back of steel plate happened under plunge depth of 0.25 mm. The weld-bonded area diameter increased with larger welding parameters, but the corresponding joint fracture loads increased and then decreased. Four failure modes including lap interface tearing (IT), upper sheet fracture (UF), outer bonding area separation (BS), and the mixed UF and BS were observed. Spot welds failed with UF possessed the maximum tensile load while joints fractured with IT showed low performance. Three different morphologies were observed on the fracture surface of the IT joints while the fracture surfaces of the joints failed with other fracture modes showed elongated strips and flocculent structures. [ABSTRACT FROM AUTHOR]

BACKGROUND: Protein degradation is the main reason of exercise induced muscle damage (ElMO). High-intensity exercise may lead to the misfolding of proteins and fonn aggregates, which is harmful to the ultrastructure of skeleton muscle. OBJECTIVE: To determine the formation and role of protein aggregate (especially the desmin aggregate) in ElMO. METHODS: Sixty-four adult male Sprague-Dawtey rats (purchased from Beijing Vital River Laboratory Animal Technology Co., Ltd., China) were randomly divided into eight groups (control, post-exercise 0, 3, 6, 12, 24, 48, and 72 hours, eight rats in each). A damage model was established by downhill running (-160, 16m/min, 90 minutes). All rats were then killed at corresponding time points to take the soleus as specimen. Severity of damage was observed histologically under a transmission electron microscope. Expression of ubiquitin in the insoluble protein of soleus muscle was detected using western blot, and expression of desmin aggregates was observed by immunofluorescence double labeling. All experimental procedures were approved by the Beijing Sport University Institutional Review Board. RESULTS AND CONCLUSION: (1) After a large-load eccentric exercise, the sarcomere of the soleus muscle was widened, the Z-line was broken, and the myofibril was broken and distorted, all of which was most serious at 12 hours after exercise, and recovered completely at 72 hours after exercise. (2) Western blot results indicated that the expression of ubiquitin in the skeletal muscle increased first and then decreased after a large-load eccentric exercise. The expression peaked at 12 hours after exercise and returned to normal at 72 hours after exercise. (3)0verall expression of desmin aggregates significantly raised (P < 0.01) instantly when the ElMO occurred. It reached the peak at 12 hours after exercise, then reduced somewhat (P < 0.01) at 24 and 48 hours, and finally recovered at 72 hours. (4)These findings indicate that desmin aggregation may be one of the causes of ElMO. [ABSTRACT FROM AUTHOR]

Two undescribed phenolic compounds, angelicols A (1) and B (2) and one undescribed coumarin rhamnoside, angelicoside A (3), together with 17 known compounds (4–20) were isolated from the roots of Angelica dahurica. Their structures were characterized by physical data analyses such as NMR, HRESIMS, and X-ray diffraction. Compounds 2, 3, 5, 6 and L-ascorbic acid (positive control) exhibited obvious DPPH radical scavenging activities with IC50 values of 0.36 mM, 0.43 mM, 0.39 mM, 0.44 mM, 0.25 mM, respectively. At a concentration of 25 μM, all compounds showed weaker tyrosinase inhibition activities (%inhibition < 5%) than kojic acid (26.00 ± 0.67%, IC50 = 44.29 ± 0.06 μM). [ABSTRACT FROM AUTHOR]

BACKGROUND: A high-intensity eccentric exercise may lead to skeletal muscle damage, endoplasmic reticulum stress, increasing misfolded proteins. Aggraphagy works as an effective way of controlling quality of proteins and plays an important role in damage repair. OBJECTIVE: To discover the activation degree of aggrephagy in the damage repair process after an overload eccentric exercise, and to discuss the role of aggrephagy in the exercise-induced muscle damage, which is supplementary to the protein degradation pathway in skeletal muscle damage. METHODS: Sixty-four male adult Sprague Dawley rats were randomly divided into a static control group (n=8) and seven exercise groups according to post-exercise time (0, 3, 6, 12, 24,48 and 72 hours, eight rats in each). Damage models were established by downhill running (-16°, 16m/min, 90 minutes). Subsequently, the histological changes of the rat soleus muscle was observed under an electron microscope and protein expressions of histone deacetylase 6 and microtubule-associated protein 1 light chain 3II/I related to aggrephagy were detected using western bot assay. RESULTS AND CONCLUSION: (1) Under the transmission electron microscope, the rat soleus muscle was disordered and widened and appeared to have transient sarcomere, the Z line was water wave-like, broken and disappeared, and the mitochondria were swollen and unevenly distributed with an unclear structure after high-intensity eccentric exercise. The model rats suffered severest muscle damage at 12 hours and recovered completely at 72 hours after high-intensity eccentric exercise. (2) After one-time eccentric exercise, the expression of histone deacetylase 6 had a transient increase. The histone deacetylase 6 expression reached the peak at 6 hours, then gradually reduced and recovered at 72 hours after exercise. The microtubule-associated protein 1 light chain 3II/I expression was significantly increased at 3 hours after exercise, reached the peak at 12 hours, then reduced significantly and recovered at 72 hours after exercise. All these findings indicate that aggrephagy transiently happens and exerts important roles in the clearance of misfolded proteins, maintenance of cellular environmental homeostasis and recovery of skeletal muscle damage. [ABSTRACT FROM AUTHOR]

One novel neoligan glucoside, Ginkgoside B (1), and one new glucose ester, 6-O-(4-hydroxyhydrocinnamoyl)-d-glucopyranose (2), along with nine known compounds (3–11) were isolated from the ethanol extract of Ginkgo biloba leaves. Their structures were elucidated by combination of spectroscopic analyses and alkaline methanolysis. The absolute configuration of compound 1 was determined by single-crystal X-ray diffraction. All the isolated compounds were evaluated for their cytotoxicity activities, and compound 11 exhibited IC50 values of 36.20 and 58.95 μM against 5637 and HeLa cell lines, respectively. [ABSTRACT FROM AUTHOR]

In this paper, Burr-X distribution with unified hybrid censored data is considered. The maximum likelihood method, the Bayesian and the E-Bayesian (the expectation of the Bayesian estimate) approaches are studied for the distribution parameter and the associated reliability function. The Bayesian and the E-Bayesian estimates are derived under LINEX and squared error loss (SEL) functions. We apply Markov chain Monte Carlo (MCMC) techniques to derive the Bayesian and the E-Bayesian estimates. Also, confidence intervals (CIs) of the maximum likelihood estimates, as well as credible intervals (CRIs) of the Bayesian and the E-Bayesian estimates, are computed. On the other hand, an example of a real data set is provided for the purpose of illustration. Finally, a numerical comparison among the proposed methods is performed. [ABSTRACT FROM AUTHOR]