Coupled modelling and sampling approaches to assess the impacts of human water management on land-sea carbon transfer

Land-sea riverine carbon transfer (LSRCT) is one of the key processes in the global carbon cycle. Although natural factors (e.g. climate, soil) influence LSRCT, human water management strategies have also been identified as a critical component. However, few systematic approaches quantifying the contribution of coupled natural and anthropogenic factors on LSRCT have been published. This study presents an integrated framework coupling hydrological modeling, field sampling and stable isotope analysis for the quantitative assessment of the impact of human water management practices (e.g. irrigation, dam construction) on LSRCT under different hydrological conditions. By applying this approach to the case study of the Nandu River, China, we find that carbon (C) concentrations originating from different land-uses (e.g. forest, cropland) are relatively stable and outlet C variations are mainly dominated by controlled runoff volumes rather than by input C concentrations. These results indicate that human water management practices are responsible for a reduction of ∼60% of riverine C at seasonal timescales, with an even greater reduction during drought conditions. Annual C discharges have been significantly reduced (e.g. 77 ± 5% in 2015 and 39 ± 11% in 2016) due to changes in human water extraction coupled with climate variation. In addition, isotope analysis also shows that C fluxes influenced by human activities (e.g. agriculture, aquaculture) could contribute the dominant particulate organic carbon under typical climatic conditions, as well as drought conditions. This research demonstrates the substantial effect that human water management practices have on the seasonal and annual fluxes of LSRCT, especially in such small basins. This work also shows the applicability of this integrated approach, using multiple tools to quantify the contribution of coupled anthropogenic and natural factors on LSRCT, and the general framework is believed to be feasible with limited modifications for larger basins in future research.Coupled modelling and sampling approaches to assess the impacts of human water management on land-sea carbon transfe

Identification and validation of critical genes with prognostic value in gastric cancer

Background: Gastric cancer (GC) is a digestive system tumor with high morbidity and mortality rates. Molecular targeted therapies, including those targeting human epidermal factor receptor 2 (HER2), have proven to be effective in clinical treatment. However, better identification and description of tumor-promoting genes in GC is still necessary for antitumor therapy.Methods: Gene expression and clinical data of GC patients were downloaded from The Cancer Genome Atlas (TCGA) and Gene Expression Omnibus (GEO) databases. Last absolute shrinkage and selection operator (LASSO) Cox regression were applied to build a prognostic model, the Prognosis Score. Functional enrichment and single-sample gene set enrichment analysis (ssGSEA) were used to explore potential mechanisms. Western blotting, RNA interference, cell migration, and wound healing assays were used to detect the expression and function of myosin light chain 9 (MYL9) in GC.Results: A four-gene prognostic model was constructed and GC patients from TCGA and meta-GEO cohorts were stratified into high-prognosis score groups or low-prognosis score groups. GC patients in the high-prognosis score group had significantly poorer overall survival (OS) than those in the low-prognosis score groups. The GC prognostic model was formulated as PrognosisScore = (0.06 × expression of BGN) - (0.008 × expression of ATP4A) + (0.12 × expression of MYL9) - (0.01 × expression of ALDH3A1). The prognosis score was identified as an independent predictor of OS. High expression of MYL9, the highest weighted gene in the prognosis score, was correlated with worse clinical outcomes. Functional analysis revealed that MYL9 is mainly associated with the biological function of epithelial-mesenchymal transition (EMT). Knockdown of MYL9 expression inhibits migration of GC cells in vitro.Conclusion: We found that PrognosisScore is potential reliable prognostic marker and verified that MYL9 promotes the migration and metastasis of GC cells

Effect of Ascorbic Acid on Mineral and Bone Disorders in Hemodialysis Patients: a Systematic Review and Meta-Analysis

Background/Aims: Hemodialysis (HD) patients often have inadequate nutrition, especially with respect to ascorbic acid (AA). It is reported that every HD session may cause a 50%– 75% decrease in plasma AA levels. Some studies have shown that supplementation of AA can change the outcome of chronic kidney disease-mineral bone disorders (CKD-MBD), but the effect of AA on HD patients with CKD-MBD remains controversial. Consequently, we decided to perform a meta-analysis to evaluate the efficacy of AA supplementation in CKD-MBD patients requiring dialysis. Methods: A search was conducted using Pubmed, EMBASE, Cochrane Central Register of Controlled Trials, Chinese National Knowledge Infrastructure (CNKI), Wanfang database and VIP information database up to April 2018 for all English and Chinese language publications. The main indicators of our study were changes in serum phosphate (P), calcium (Ca) and parathyroid hormone (PTH) levels after AA treatment. The efficacy of AA was evaluated by weighted mean difference (WMD) and confidence intervals (CI). Cardiovascular events, mortality and adverse events reported during the experiment were also noted. Results: In total, 371 patients in six studies were involved in this meta-analysis. Compared to placebo, AA treatment had no positive effect on serum P (353 patients; WMD = -0.05; 95% CI, -0.3 to 0.2; I2 = 28%) or PTH levels (275 patients; WMD = -17.04; 95%CI, -63.79 to 29.72; I2 = 75%). The pooled mean difference of the change of Ca levels from baseline was higher in the AA therapy group versus placebo (353 patients; WMD = 0.15; 95% CI, 0.01 to 0.3; I2 = 0%). No side effects were observed. Conclusion: Our systematic review and meta-analysis does not support prescription of AA to HD patients with CKD-MBD. AA had no positive effect on CKD-MBD patients as it couldn’t influence the serum P or PTH levels but did raise serum Ca levels in the short-term

Multistage Machining Process Design And Optimization Using Error Equivalence Method

In design of a multistage machining process, process tolerance allocation at each stage and design of process layouts, in particular, the fixture layouts, should be optimized considering dimensional tolerance stackup or variation propagation. When multiple error sources contribute to the tolerance stackup, the dimensionality of the design space could be large and design solution may not be unique. One strategy is to prioritize the allocation of tolerances to different error sources at each stage through proper selection of cost functions. Considering the fact that the cost function selection can be very subjective and the knowledge regarding cost structures is very limited, we propose a hierarchical process design method using error equivalence concept to aggregate multiple error sources together. The main idea is to allocate tolerances to the aggregated error sources at each stage and then further distribute the tolerance to individual error sources through cost analysis. The advantage is two-fold: (1) limiting the impact of cost function selection within individual stages to avoid overhaul of process design caused by subtle change in cost functions, and (2) enabling the optimization of fixture layouts to reduce the overall tolerance stackup due to multiple error sources. To reduce computational load in optimizing process layouts, a computer experiment model is developed to explore a large number of process design alternatives. The robustness of the optimal tolerance is evaluated through sensitivity analysis, which provides guidance for process design. We illustrate the error-equivalence-based process design method by a multistage machining process. The results have shown that the proposed method could significantly reduce the design space and increase the design efficiency. Copyright © 2009 by ASME

Diagnosis Of Multiple Error Sources Under Variation Equivalence

Variation equivalence concerns the mechanism by which multiple types of error sources (e.g., the fixture error, machine tool error and datum error) result in identical variation patterns on part features. This phenomenon poses challenges in distinguishing the effects from multiple variation sources and thereby diagnoses the root cause. This paper improves the root cause diagnosis taking into account the variation equivalence phenomenon. Variation equivalence model is established to study the equivalent properties among different variation sources. Through exploring a number of possible equivalent variations scenarios, an equivalent variation patterns library is created for an improved interpretation of fault patterns by considering variation equivalence among multiple error sources. Combined with the library, this paper proposes an excitation-response path method to distinguish multiple error sources under variation equivalence. A case study verifies the diagnostic approach

Takaful in Singapore : a study on the concept, opportunities, efficiency and future of Takaful.

With the growing demand for Islamic insurance, especially in the Middle East and South-East Asia, we seek to explore the further development of such a system in Singapore. From the successful experiences of other Islamic countries and conventional insurance operators which have tapped into the vast Islamic insurance’s market, we anticipate that it will provide a competitive edge to Singapore in becoming a more holistic insurance hub in Asia. Through analyzing the principles behind Islamic insurance, we seek to have a deeper understanding of the workings of the Islamic world. Our research aims to explore how to further the development of Islamic insurance through efficiency analysis of life insurers in Singapore. This will bring about higher productivity. In addition, we have also examined several issues which may affect this development locally. In summary, the development of Islamic insurance can provide customers with more alternatives. Our analysis has shown that for Islamic insurance operators to be more productive, they should aim for technical change rather than efficiency change

The association of body mass index with difficult tracheal intubation management by direct laryngoscopy: a meta-analysis

Abstract Background Obesity is a serious disorder and may bring about many difficulties of perioperative management. A systematic review was conducted to assess the association between obesity and difficult intubation. Methods We searched electronic databases for related reviews and references of meta-analyses on August 14, 2017. The databases of PubMed, Embase, and the Cochrane controlled trials register were searched compared obese with non-obese patients in which difficult intubation rate of the adult population were retrieved. Patients with a BMI ≥ 30 kg·m− 2 were considered obese. The primary outcome was difficult tracheal intubation; secondary outcomes were the rates of difficult laryngoscopy and Mallampati score ≥ 3. This review included papers published from 1998 to 2015. Results This review included 204,303 participants in 16 studies. There was a statistically significant association between obesity and risk of difficult tracheal intubation (pooled RR = 2.04, 95% CI: 1.16–3.59, p = 0.01; I2 = 71%, p = 0.008, Power = 1.0). It also showed significantly association between obesity and risk of difficult laryngoscopy (pooled RR = 1.54, 95% CI: 1.25–1.89, p < 0.0001; I2 = 45%, p = 0.07, Power = 1.0), obesity and risk of Mallampati score ≥ 3 (pooled RR = 1.83, 95% CI: 1.24–2.69, p = 0.002; I2 = 81%, p < 0.00001, Power = 0.93). However, there were no association of obesity and risks of difficult intubation compared with non-obesity in the cohort studies (pooled RR = 3.41, 95% CI: 0.88–13.23, p = 0.08; I2 = 50%, p = 0.14) and the elective tracheal intubation (pooled RR = 2.31, 95% CI: 0.76–6.99, p = 0.14; I2 = 73%, p = 0.01), no associated with an increased risk of difficult laryngoscopy in the sniffing position (pooled RR = 2.00, 95% CI: 0.97–4.15, p = 0.06; I2 = 67%, p = 0.03). Conclusion Obesity was associated with an increased risk of difficult intubation, difficult laryngoscopy and Mallampati score ≥ 3 in adults patients undergoing general surgical procedures. However, there were no association of obesity and risks of difficult intubation compared with non-obesity in the cohort studies and the elective tracheal intubation, no associated with an increased risk of difficult laryngoscopy in the sniffing position. Future analyses should explore the association of BMI and difficult airway