147 research outputs found

    Attenuation performance of geosynthetic sorption sheets against arsenic subjected to compressive stresses

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    The attenuation layer method has been considered an effective countermeasure to deal with excavated soils and rocks containing geogenic toxic elements like arsenic (As). The geosynthetic sorption sheet is a geosynthetic product that can be employed in the attenuation layer method applications as a sorption material. The sorption sheets used in the attenuation layer will be inevitably subjected to overburdened loads in the field. In this study, laboratory column experiments are conducted to evaluate the attenuation performance of the geosynthetic sorption sheets coated with hydrotalcite as sorbent against As under different overburden pressure conditions (10, 100, and 200 kPa). Experimental results showed that the cumulative sorption masses of As for 200 kPa cases are approximately 10.5–13.3 times greater than that for 10 kPa cases. Microstructure characterizations of the geosynthetic sorption sheet before and after loading were also detected. More compacted and involved fiber configuration as a result of higher loading produces a more effective contact between As solution and hydrotalcite. The presence of partial dissolution of hydrotalcite is confirmed through the chemical analysis of effluent. However, hydrotalcite would gradually become stable during continuous use

    A ZigBee/Wi-Fi Cooperative Channel Control Method and Its Prototyping

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    Coexistence between ZigBee and Wi-Fi technologies, which operate within the same frequency band, is increasing with the widespread use of the IoT (Internet of Things). ZigBee devices suffer significant decrease in the sink arrival rate of packets in the presence of Wi-Fi interference. To overcome this problem, many channel control methods have been proposed. These existing methods switch only ZigBee channels to avoid interference with Wi-Fi. In contrast, we propose a cooperative channel control method for improving ZigBee packet arrival rate by controlling both the Wi-Fi and ZigBee channels. Specifically, the proposed method not only controls ZigBee devices and channels but also requests a temporary pause in the use of specific Wi-Fi channels. Finally, we show the effectiveness of the proposed method from the viewpoints of ZigBee’s packet arrival rate and applications’ satisfaction using computer simulations. In addition, the effective action of the proposed method is also demonstrated by experiments with prototyping

    Premorbid Clinical Frailty Score and 30‐day mortality among older adults in the emergency department

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    Objectives: The association between frailty and short-term prognosis has not been established in critically ill older adults presenting to the emergency department. We sought to examine the association between premorbid frailty and 30-day mortality in this patient population. Methods: This is a retrospective observational study on older adults aged over 75 who were triaged as Level 1 resuscitation with subsequent admissions to intermediate units or intensive care units (ICUs) in a single critical care center, from January to December 2019. We excluded patients with out-of-hospital cardiac arrest or those transferred from other hospitals. Frailty was evaluated by the Clinical Frailty Scale (CFS) from the patients' chart reviews. The primary outcome was 30-day mortality, and we examined the association between frailty scored on the CFS and 30-day mortality using a multivariable logistic regression model with CFS 1-4 as a reference. Results: A total of 544 patients, median age: 82 years (interquartile rang 78 to 87), were included in the study. Of these, 29% were in shock and 33% were in respiratory failure. The overall 30-day mortality was 15.1%. The adjusted risk difference (95% confidence interval [CI]) in mortality for CFS 5, CFS 6, and CFS 7-9 was 6.3% (-3.4 to 15.9), 11.2% (0.4 to 22.0), and 17.7% (5.3 to 30.1), respectively; and the adjusted risk ratio (95% CI) was 1.45 (0.87 to 2.41), 1.85 (1.13 to 3.03), and 2.44 (1.50 to 3.96), respectively. Conclusion: The risk of 30-day mortality increased as frailty advanced in critically ill older adults. Given this high risk of short-term outcomes, ED clinicians should consider goals of care conversations carefully to avoid unwanted medical care for these patients

    Fair Routing for Overlapped Cooperative Heterogeneous Wireless Sensor Networks

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    In recent years, as WSNs (Wireless Sensor Networks) are diffused widely, multiple overlapping WSNs constructed on the same area become more common. In such a situation, their lifetime is expected to be extended by cooperative packet forwarding. Although some researchers have studied about cooperation in multiple WSNs, most of them do not consider the heterogeneity in characteristics of each WSN such as battery capacity, operation start time, the number of nodes, nodes locations, energy consumption, packet size and/or data transmission timing, and so on. In a heterogeneous environment, naive lifetime improvement with cooperation may not be fair. In this paper, we propose a fair cooperative routing method for heterogeneous overlapped WSNs. It introduces an energy pool to maintain the total amount of energy consumption by cooperative forwarding. The energy pool plays a role of broker for fair cooperation. Finally, simulation results show the excellent performance of the proposed method

    Impact of Gba2 on neuronopathic Gaucher’s disease and α-synuclein accumulation in medaka (Oryzias latipes)

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    Homozygous mutations in the lysosomal glucocerebrosidase gene, GBA1, cause Gaucher's disease (GD), while heterozygous mutations in GBA1 are a strong risk factor for Parkinson's disease (PD), whose pathological hallmark is intraneuronal α-synuclein (asyn) aggregates. We previously reported that gba1 knockout (KO) medaka exhibited glucosylceramide accumulation and neuronopathic GD phenotypes, including short lifespan, the dopaminergic and noradrenergic neuronal cell loss, microglial activation, and swimming abnormality, with asyn accumulation in the brains. A recent study reported that deletion of GBA2, non-lysosomal glucocerebrosidase, in a non-neuronopathic GD mouse model rescued its phenotypes. In the present study, we generated gba2 KO medaka and examined the effect of Gba2 deletion on the phenotypes of gba1 KO medaka. The Gba2 deletion in gba1 KO medaka resulted in the exacerbation of glucosylceramide accumulation and no improvement in neuronopathic GD pathological changes, asyn accumulation, or swimming abnormalities. Meanwhile, though gba2 KO medaka did not show any apparent phenotypes, biochemical analysis revealed asyn accumulation in the brains. gba2 KO medaka showed a trend towards an increase in sphingolipids in the brains, which is one of the possible causes of asyn accumulation. In conclusion, this study demonstrated that the deletion of Gba2 does not rescue the pathological changes or behavioral abnormalities of gba1 KO medaka, and GBA2 represents a novel factor affecting asyn accumulation in the brains

    HTR1A polymorphisms and clinical efficacy of antipsychotic drug treatment in schizophrenia: A meta-analysis

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    Background: This meta-analysis was conducted to evaluate whether HTR1A gene polymorphisms impact the efficacy of antipsychotic drugs in patients with schizophrenia. Methods: Candidate gene studies that were published in English up to August 6, 2015 were identified by a literature search of PubMed, Web of Science, and Google scholar. Data were pooled from individual clinical trials considering overall symptoms, positive symptoms and negative symptoms, and standard mean differences were calculated by applying a random-effects model. Results: The present meta-analysis included a total of 1281 patients from 10 studies. Three polymorphisms of HTR1A (rs6295, rs878567, and rs1423691) were selected for the analysis. In the pooled data from all studies, none of these HTR1A polymorphisms correlated significantly with either overall symptoms or positive symptoms. However, C allele carriers of the rs6295 polymorphism showed a significantly greater negative symptoms improvement than G allele carriers (P = .04, standardized mean difference = -0.14, 95%CI = 0.01 to 0.28). Conclusions: The results of our present analysis indicate that the HTR1A rs6295 polymorphism may impact negative symptoms improvement but not on either overall symptoms or positive symptoms improvement. However, this metaanalysis was based on a small number of studies and patients, and the effect size on negative symptoms was small. Given this limitation, the results should be confirmed by further investigations

    Critical role of the MCAM-ETV4 axis triggered by extracellular S100A8/A9 in breast cancer aggressiveness

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    Metastatic breast cancer is the leading cause of cancer-associated death in women. The progression of this fatal disease is associated with inflammatory responses that promote cancer cell growth and dissemination, eventually leading to a reduction of overall survival. However, the mechanism(s) of the inflammation-boosted cancer progression remains unclear. In this study, we found for the first time that an extracellular cytokine, S100A8/A9, accelerates breast cancer growth and metastasis upon binding to a cell surface receptor, melanoma cell adhesion molecule (MCAM). Our molecular analyses revealed an important role of ETS translocation variant 4 (ETV4), which is significantly activated in the region downstream of MCAM upon S100A8/A9 stimulation, in breast cancer progression in vitro as well as in vivo. The MCAM-mediated activation of ETV4 induced a mobile phenotype called epithelial-mesenchymal transition (EMT) in cells, since we found that ETV4 transcriptionally upregulates ZEB1, a strong EMT inducer, at a very high level. In contrast, downregulation of either MCAM or ETV4 repressed EMT, resulting in greatly weakened tumor growth and lung metastasis. Overall, our results revealed that ETV4 is a novel transcription factor regulated by the S100A8/A9-MCAM axis, which leads to EMT through ZEB1 and thereby to metastasis in breast cancer cells. Thus, therapeutic strategies based on our findings might improve patient outcomes
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