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In mechanical sugarcane harvesting, the basecutter is a critical component determining the basecutting quality and energy consumption, both of which have a close relationship with basecutting times (number of contacts between sugarcane and basecutting blades to completely cut cane stools). Therefore, the purpose of this study was to investigate the relationship between the influencing factors and basecutting times by employing a high-speed camera. In this paper, the influencing factors were determined to be the rotational speed (RS) and tilt angle (TA) of the cutting disk, sugarcane stalk feeding rate (FR), and sugarcane stool diameter (SD). Four single-factor experiments and an orthogonal experiment (four factors and four levels) were carried out. In addition, two methods were employed to analyze the experimental data: analysis of range (ANOR) and analysis of variance (ANOVA). The results showed that RS, TA, and SD had positive effects on the basecutting times, while FR had a negative effect. In addition, the order of influence of the above four factors on the basecutting times, obtained by ANOR, was FR > SD > RS > TA (2.625 > 1.75 > 1.425 > 1), and the optimal combination (150 rpm of RS, 5° of TA, 60 mm of SD, and 1.3 m/s of FR) to minimize the basecutting times was also determined. Based on the ANOVA results, basecutting times were significantly affected by FR and RS (p = 0.008, 0.047 0.05). The results of this study will provide a reference for engineers to design and optimize sugarcane basecutters.

HighlightsThis study focused on the base cutting energy consumption for sugarcane stools instead of single stalks, thus being more consistent with actual field harvesting.The energy consumption increased with increasing rotational speed (RS) and stool diameter (SD), while it decreased with increasing tilt angle (TA) and feed rate (FR).Each pair of levels of each factor was compared using Duncan’s multiple range test. Three factors (RS, SD, and FR) had significant effects on energy consumption at 95% confidence level, while one factor (TA) had no significant effect.The order of influence and the optimal combination of the four factors to minimize the energy consumed during base cutting were determined.Abstract. Previous studies on contra-rotating basecutter designs based on supported cutting have mainly focused on the base cutting energy consumption for single sugarcane stalks instead of sugarcane stools. However, in the actual base cutting process, a basecutter typically cuts multiple sugarcane stalks (in one sugarcane stool) simultaneously. Therefore, this study investigated how the rotational speed (RS) and tilt angle (TA) of the cutting discs, the sugarcane stool diameter (SD), and the feed rate (FR) affected the energy consumed when cutting cane stools using a contra-rotating cutting platform. Four single-factor experiments and an orthogonal experiment were performed using a Taguchi orthogonal experimental design, and each group was replicated five times. The results of the single-factor experiments showed that the energy consumption was proportional to RS and SD, while it was negatively correlated with TA and FR. The significance of the difference between each pair of levels of each factor was investigated using Duncan’s multiple range test. According to the results of the orthogonal experiment, RS, SD, and FR had significant influences on the base cutting energy consumption at the 95% confidence level; however, TA had no significant influence. The order of influence of the four factors was SD > FR > RS > TA (18.45 > 18.39 > 12.91 > 9.06), and the optimal factor-level combination for minimizing the cutting energy was RS2, TA4, SD1, and FR3 (200 rpm disc RS, 20° disc TA, 60 mm SD, and 1.0 m s-1 FR). An understanding of the relationships between energy consumption and its influencing factors can serve as a valuable reference for researchers seeking to optimize the design of contra-rotating basecutters, which could lead to increased energy efficiency and a reduction in energy consumption during sugarcane harvesting. Keywords: Contra-rotating basecutter, Energy consumption, Orthogonal experiment, Single-factor experiment, Sugarcane stools, Supported cutting.

HighlightsAn under-the-ground basecutting mode was employed, which is different from the typical above-the-ground basecutting mode.A series of field experiments were carried out using the response surface methodology (RSM).The complicated effect of critical parameters on three indicators (stubble breaking index, stubble uprooting index, and power consumption) was explored.The optimal values of critical parameters were determined using a multi-objective optimization method.Abstract. Basecutting is an important process in mechanical sugarcane harvesting, thus, it’s necessary to develop a high-efficient basecutter. The previous research about basecutting has mainly focused on the above-the-ground basecutting instead of under-the-ground basecutting. Therefore, the objective of this study was to analyze how the critical structural parameters, such as blade number (BN), oblique angle and bevel angle of blades (OA, BA), affect the cutting performance of a sugarcane harvester with an under-the-ground basecutting mode. A series of field tests were carried out using Liugong sugarcane harvester. The experimental indexes were determined as stubble breaking index (BI), stubble uprooting index (UI), and power consumption (PC). The ANOVA results indicated that three regression models of indicators were significant, and were in agreement with the test data. Additionally, it was concluded that OA and BN were the two most important factors when optimizing BI, UI, and PC. BA was the last factor to be considered although it had significant effect on BI and UI. The multi-objective optimization results showed that the optimal parameter combination was 3 of BN, 10° of OA, and 20° of BA, and the corresponding BI, UI, and PC reached the minimum. For sugarcane growers, reduced stubble damage and power consumption could increase the sugarcane germination and decrease the harvesting cost, respectively. For sugarcane mills, this cutting mode might cause potential decrease in sugar quality, specifically sediment levels. However, this disadvantage could be overcome by optimizing basecutter parameters. Keywords: Basecutter, Cutting mode, Power consumption, Stubble breaking, Stubble uprooting, Under-the-ground basecutting.

HighlightsThis article is focused on the technology review of sugarcane basecutters.Two cutting theories and two cutting modes are briefly reviewed.Three optimization methods of parameters for the sugarcane basecutter are summarized.Four potential research interests to improve the basecutting quality are discussed.Abstract. Basecutter is a core component of a sugarcane harvester, and its performance significantly influences cane yield and harvesting efficiency. Therefore, it is meaningful to conduct a critical review of sugarcane basecutters. In this article, an introduction about basecutter structure was performed first; then two cutting theories (support/free cutting) and two cutting modes (straight/sliding cutting) were briefly reviewed; and the advantages and disadvantages of different cutting modes were summarized. It was followed by a comprehensive introduction of three optimization methods: theoretical analysis and simulation, indoor experiments, and field experiments. Finally, four potential research interests in improving basecutting quality and exploring the stubble damage process were discussed. In this review, the comprehensive, detailed, and accurate information about sugarcane basecutter was expected to provide engineers with a technology reference to improve the basecutting performance. Keywords: Basecutter, Cutting theories and modes, Optimization methods, Potential research interests, Sugarcane harvester.

Reciprocity is a behavior which makes human society more harmonious. It is also a common concept in behavioral economics. There are many factors can influence trust and reciprocity between people. In this study, we utilized some previous experiments’ results done by predecessors to expect the relationship between gender and reciprocity in certain age group-university students (Teenagers). Combining with game theory, particularly the investment game, our research will exhibit the likelihood of being trusted and trustworthiness level between men and women when they make decision. The overview of this essay comprises four sections: The introduction of reciprocity, the literature review of two articles about age and gender respectively, the experiment design and the conclusion. Our methodology mainly based on the improvement of double blind trials and the hypothesis is: The trust between the same gender is easier to achieve compared to different gender. Furthermore, the final part of this essay will analyze the improvement and suggest some recommendations.

BACKGROUND: Uric acid was once considered an effective endogenous antioxidant, but now more and more evidence shows that it may play a significant role in the pathophysiology of cardiovascular diseases.OBJECTIVES: It has not been clear that UA is a sign of poor prognosis or a risk factor for CVD. Our aim is to figure out the exact relationship between CVD and uric acid. METHODS: We studied 3356 publications in the past 44 years through MEDLINE, EMBASE, and Cochrane library searches, and selected 22 studies that met our inclusion criteria. RESULTS: The meta-analysis showed that hyperuricemia was associated with an increased risk of death from CVD (RR=1.37; 95% CI:1.29-1.45; I2=31.4%, P=0.157). Sensitivity analysis reviewed several potential sources of heterogeneity between studies, such as average SUA level, study location, and outcome indicators.

Basecutter is a core component of the sugarcane harvester and its performance greatly influences the cane yield and the efficiency of harvester. Therefore, it is meaningful to conduct a critical technology review on the current research status of the basecutters for sugarcane harvesting. In this paper, a brief introduction was performed firstly, then two cutting theories (supported / free cutting theory) and two cutting modes (straight / sliding cutting) were briefly reviewed, and the advantages and disadvantages of different cutting modes were summarized. It is followed by a comprehensive introduction of three optimizing methods of structural and kinematic parameters for the sugarcane basecutter: theoretical analysis and simulation, indoor experiments, and field experiments. Finally, some potential research interests to explore the stubble damaging process and improve the basecutting quality were discussed. The technology review is expected to provide researchers with more comprehensive, detailed, and accurate information about the basecutter in harvesting sugarcanes, which will also provide a technology reference to improve its basecutting performance.

Drug delivery systems are required to be safe, minimally invasive and effectively delivery drug to the target tissues. But delivery drugs to the eye has not yet satisfied this need. Here, we focused on examining the distribution of dexamethasone (DEX) in ocular and plasmic samples following controllable continuous sub-Tenon drug delivery (CCSDD) of dexamethasone disodium phosphate (DEXP) in rabbit, and to compare that with two traditional routes: subconjunctival injection and intravenous injection. The DEX concentration was analyzed by Shimadzu LC–MS 2010 system. In CCSDD group, during observed 24 h, the mean DEX level in collected samples from highest to lowest following in order: sclera, cornea, retina/choroid, iris, plasma, aqueous humor, lens and vitreous body. In ocular solid tissue, the DEX level in posterior segment is higher than in anatomic corresponding anterior segment, but it is opposite in ocular fluid tissue. High levels of DEX were maintained at 12 h in the ocular tissue immediately after the administration. Even at 24 h, the mean DEX concentration was 31.72 ng/ml and 22.40 ng/ml in aqueous and vitreous, respectively. In CCSDD group, the ocular DEX exposure (AUC0-24) is much higher and plasma exposure is much less than IV group, and it is also similar in SC group except iris. The amount of DEX levels are markedly increased in ocular tissues but it yield lower plasma levels indicating reduction of systemic absorption by CCSDD. Thus, CCSDD is an effective method of delivering DEX into anterior and posterior segment of the eye.

Corticosteroids have been used for treatment of posterior segment eye diseases, but the delivery of drug to the posterior segments is still a problem to resolve. In our study, we explore the feasibility of Sub-tenon’s Controllable Continuous Drug Delivery to ocular posterior segment. Controllable continuous sub-tenon drug delivery (CCSDD) system, intravenous injections (IV) and sub-conjunctival injections (SC) were used to deliver dexamethasone disodium phosphate (DEXP) in rabbits, the dexamethasone concentration was measured in the ocular posterior segment tissue by Shimadzu LC-MS 2010 system at different time points in 24 h after first dose injection. Levels of dexamethasone were significantly higher at 12, 24 h in CCSDD than two other approaches, and at 3, 6 h in CCSDD than IV in vitreous body (p

Purpose: To compare the demethylvancomycin’s diffusion–deposition characteristics in the ocular solid tissues of sustained subtenon drug delivery with subconjunctival injection. Method: Sixty adult white rabbits were randomly assigned to the subtenon drug delivery group and the subconjunctival injection group. The subtenon drug delivery group was continuously infused demethylvancomycin to the subtenon of rabbits. The subconjunctival injection group was injected demethylvancomycin to the subconjunctival of rabbits. Cornea, iris and sclera were collected for high-performance liquid chromatography analyses to determine drug concentrations at one hour, three hours, six hours, 12 h and 24 h of drug administration. WinNonlin 6.3 was used to calculate the parameters of cumulative area under the curve (AUCcum) of demethylvancomycin. Results: The peak levels of demethylvancomycin concentration of the subtenon drug delivery group and the subconjunctival injection group were 92.406 ± 21.555 and 51.778 ± 14.001 μg/g in cornea, 28.451 ± 10.229 μg/g and 42.271 ± 27.291 μg/g in iris, 153.166 ± 51.738 μg/g and 57.423 ± 18.480 μg/g in sclera. The differences of concentrations between the two groups in cornea and sclera were statistically significant (F = 487.775, p

Few studies have reported the relationship between retinal artery occlusion (RAO) and plasma homocysteine (Hcy) levels. Our goal was to evaluate the association between the plasma Hcy level and the risk of RAO disease. Several databases were searched for all published studies that involved Hcy and RAO. Six studies evaluated hyperhomocysteinemia (hHcy) in retinal artery occlusion patients and controls; the incidence of hHcy in patients with RAO was higher than the control and the pooled odds ratio (OR) was 6.64 (95% confidence interval (CI): 3.42, 12.89). Subgroup analyses showed that the ORs were 4.77 (95% CI: 2.69, 8.46) in Western countries, 22.19 (95% CI: 2.46, 200.37) in Asian countries, 9.70 (95% CI: 4.43, 21.20) in the age matched group, 11.41 (95% CI: 3.32, 39.18) in the sex matched group, 9.70 (95% CI: 4.37, 21.53) in the healthy control group, and 6.82 (95% CI: 4.19, 11.10) in the sample size >30. The mean plasma Hcy level from 5 case-control studies was higher than controls, and the weighted mean difference (WMD) was 6.54 (95% CI: 2.79, 10.29). Retinal artery occlusion is associated with elevated plasma Hcy levels. Our study results suggest that hHcy is probably an independent risk factor for RAO.

The aim of this study was to investigate the effect of advanced glycation end products (AGEs) on the expression of hypoxia-inducible factor-1α (HIF-1α) and vascular endothelial growth factor (VEGF) proteins in RF/6A cells cultured in vitro, and to investigate the association between the expression of HIF-1α and VEGF proteins. RF/6A cells were cultured in vitro and treated with AGEs and non-glycated albumin control at various concentrations (0, 50, 100, 200, 400 and 800 mg/l) for 24 h. The expression of the VEGF protein was detected by ELISA, and western blot analysis was used to determine the levels of HIF-1α protein. The expression of HIF-1α and VEGF proteins was significantly higher in the AGE group compared with the non-glycated control group (all P

Background and objective Conventional methods to treat intraocular diseases are invasive or associated with adverse effects. A minimally invasive means of sustained-release drug delivery to the vitreous is required. This study evaluated a novel device for subtenon drug delivery to the vitreous, relative to a single subconjunctival injection. Methods Sixty adult New Zealand White rabbits were randomly assigned to receive demethylvancomycin (DMV) by continuous subtenon delivery with the flow rate of 0.1 ml/hr for 24 hr, or as a single 0.3 ml subconjunctival injection in the right eyes. Rabbits were killed in subgroups of six at 1, 3, 6, 12 and 24 hr. The DMV concentration of the vitreous humour of the right eye was analysed by high-performance liquid chromatography. Results Overall, the vitreous DMV concentration of the subtenon group was significantly higher than that of the subconjunctival group (F = 25.928, p = 0.001). The DMV concentration of the subtenon group was also significantly higher than that of the subconjunctival group at 3, 6, 12 and 24 hr (t = 2.457, 5.064, 3.085, 4.207; p = 0.04, 0.01, 0.018, 0.004, respectively). In the subtenon group, the DMV concentration reached maximum (2.41 ± 0.67 μg/ml) at 6 hr, and at 24 hr was 2.37 ± 1.23 μg/ml. In the subconjunctival group, the DMV concentration reached maximum (0.48 ± 0.27 μg/ml) at 1 hr and declined to 0.09 ± 0.05 μg/ml at 24 hr. Conclusion Subtenon application with this novel minimally invasive design is an effective method for delivering an appropriate drug to the vitreous in a sustained and controllable amount.

Background: Retinitis pigmentosa (RP) is a group of inherited retinal dystrophies characterized by night blindness, progressive peripheral visual field loss, and loss of central vision. Fifty-three RP pathogenic genes are responsible for RP. Pre-mRNA processing factor 31(PRPF31) gene is the third most common cause of autosomal dominant retinitis pigmentosa (adRP), and so far more than 40 mutations in PRPF31 have been detected. Purpose: To identify the underlying genetic defect in a five-generation Chinese family affected with adRP and to study the genotype-phenotype relationship of this family. Methods: Detailed clinical investigations were undertaken and peripheral blood samples were collected from 25 individuals. Microsatellite (STR) markers tightly linked to genes known to be responsible for adRP were selected for linkage analysis. Exons and adjacent splice junctions of the candidate gene were amplified and sequenced. Results: This adRP family exhibited an incomplete penetrance of the RP phenotype. In affected individuals, age of disease onset was from infancy to 4 years of age. Typical RP features were associated with this mutation. Linkage analysis identified a maximum two-point LOD score of 3.20 with D19S418, which is close to PRPF31. A mutation PRPF31: (c.358-359 del AA) was identified by linkage analysis. Conclusions :A PRPF31 mutation was identified to be responsible for adRP in a large Chinese family. Our findings expand the mutation spectrum of RP in the Chinese population.