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91.
Mahnaz
M. Abdi Nur Farhana Waheeda Mohd Azli Hong Ngee Lim Paridah Md Tahir Gholamreza Karimi Yeoh Beng Hoong Mohammad Khorram 《RSC advances》2018,8(6):2978
In this research, tannin (TA) extracted from Acacia mangium and a cationic surfactant, cetyltrimethylammonium bromide (CTAB), were used to modify and enhance the physical and electrochemical properties of a polypyrrole (PPy) composite. Brunauer–Emmett–Teller (BET) analysis presented a higher degree of surface area and porosity for the PPy/TA/CTAB nanocomposite. A highly porous and rod like structure with a lumpy surface was observed for PPy/TA prepared in the presence of CTAB by Field Emission Scanning Electron Microscopy (FESEM) and Transmission Electron Microscopy (TEM). Cyclic voltammograms of the modified SPE electrode using PPy/TA/CTAB displayed an enhanced current response compared to the electrode modified with only PPy or PPy/TA. Electrochemical Impedance Spectroscopy (EIS) exhibited a lower value of charge transfer resistance (Rct) and higher electron transfer for the modified electrode, making the nanocomposite a promising candidate for biosensor application.Tannin (TA) extracted from Acacia mangium and a cationic surfactant, cetyltrimethylammonium bromide (CTAB), were used to modify and enhance the physical and electrochemical properties of polypyrrole (PPy) composite. 相似文献
92.
Diego Serrano-Muñoz Juan Avendaño-Coy Cristina Simón-Martínez Julian Taylor Julio Gómez-Soriano 《Journal of neuroengineering and rehabilitation》2018,15(1):103
Background
High-frequency alternating currents of greater than 1 kHz applied on peripheral nerves has been used in animal studies to produce a motor nerve block. It has been evidenced that frequencies higher than 5 kHz are necessary to produce a complete peripheral nerve block in primates, whose nerve thickness is more similar to humans. The aim of the study was to determine the effect on muscle strength after the application of a high-frequency stimulation at 5 and 10 kHz compared to sham stimulation in healthy volunteers.Findings
Transcutaneous stimulation at 5 kHz, 10 kHz and sham stimulation were applied to eleven healthy volunteers over the ulnar and median nerves for 20 min. Maximal handgrip strength was measured before, during, immediately after the intervention, and 10 min after the end of intervention. The 10 kHz stimulation showed a lower handgrip strength during the intervention (28.1 N, SEM 3.9) when compared to 5 kHz (31.1 N, SEM 3.6; p?<?0.001) and to sham stimulation (33.7 N, SEM 3.9; p?<?0.001). Furthermore, only stimulation at 10 kHz decreased handgrip strength when compared to baseline.Conclusions
These findings suggest high-frequency stimulation has an inhibitory effect over muscle strength. Future studies are required in patients that are characterized by motor hyperactive such as spasticity or tremors.Clinical trial registration
NCT, NCT03169049. Registered on 30 May 201793.
94.
Scott D. Rhodes Lilli Mann Florence M. Simán Eunyoung Song Jorge Alonzo Mario Downs Emma Lawlor Omar Martinez Christina J. Sun Mary Claire O’Brien Beth A. Reboussin Mark A. Hall 《American journal of public health》2015,105(2):329-337
Objectives. We sought to understand how local immigration enforcement policies affect the utilization of health services among immigrant Hispanics/Latinos in North Carolina.Methods. In 2012, we analyzed vital records data to determine whether local implementation of section 287(g) of the Immigration and Nationality Act and the Secure Communities program, which authorizes local law enforcement agencies to enforce federal immigration laws, affected the prenatal care utilization of Hispanics/Latinas. We also conducted 6 focus groups and 17 interviews with Hispanic/Latino persons across North Carolina to explore the impact of immigration policies on their utilization of health services.Results. We found no significant differences in utilization of prenatal care before and after implementation of section 287(g), but we did find that, in individual-level analysis, Hispanic/Latina mothers sought prenatal care later and had inadequate care when compared with non-Hispanic/Latina mothers. Participants reported profound mistrust of health services, avoiding health services, and sacrificing their health and the health of their family members.Conclusions. Fear of immigration enforcement policies is generalized across counties. Interventions are needed to increase immigrant Hispanics/Latinos’ understanding of their rights and eligibility to utilize health services. Policy-level initiatives are also needed (e.g., driver’s licenses) to help undocumented persons access and utilize these services.Federal immigration enforcement policies have been increasingly delegated to state and local jurisdictions, leading to increased enforcement activities by local police. This shift has resulted largely from the implementation of 2 federal initiatives: section 287(g) of the Immigration and Nationality Act and the Secure Communities program. Section 287(g) authorizes Immigration and Custom Enforcement to enter into agreements with state and local law enforcement agencies to enforce federal immigration law during their regular, daily law enforcement activities. The original intention was to “target and remove undocumented immigrants convicted of violent crimes, human smuggling, gang/organized crime activity, sexual-related offenses, narcotics smuggling and money laundering.”1 Added to the Immigration and Nationality Act in 1996, section 287(g) was not widely used in its first decade, but its use accelerated in the mid- to late 2000s.2,3The Secure Communities program differs from section 287(g) in that it does not authorize local enforcement bodies to arrest individuals for federal immigration violations. Instead, when individuals are arrested for nonimmigration matters, the Secure Communities program facilitates the sharing of local arrestees’ fingerprints and information with Immigration and Custom Enforcement and the Federal Bureau of Investigation, which checks them against immigration databases. If these checks reveal that an individual is unlawfully present in the United States or otherwise removable because of a criminal conviction, Immigration and Custom Enforcement takes enforcement action.4Some evidence suggests that both section 287(g) and the Secure Communities program contribute to Hispanic/Latino immigrants’ general mistrust of local law enforcement and fear of utilizing a variety of public services, such as police protection and emergency services.2,5–7 Although many immigrant Hispanics/Latinos in the United States experience barriers to care because of a lack of bilingual and bicultural services, low health literacy, insufficient public transportation, and limited knowledge of available health services,8–12 studies have suggested that individuals lacking legal status may have more difficulty obtaining health services and may experience worse health outcomes than do individuals with legal status.13–18 Among immigrant Hispanics/Latinos, the fear of deportation, a lack of required forms of documentation, interaction with law enforcement personnel, and racial profiling are factors also associated with reduced utilization of health services and worse health.6,19–22 Such fears lead to incomplete sequences of care,19,20,23,24 promote the use of nonstandard and unsafe contingencies for care,16,25–27 and contribute to public health hazards, as immigrants delay preventive care or treatment.13,22,28 These fears further affect long-term health outcomes as immigrant Hispanics/Latinos alter their physical activity, food purchasing behaviors, and food consumption because of concerns about being in public.29 They may withhold information from health care providers19 and experience high levels of stress, leading to compromised mental health.20,30,31The Patient Protection and Affordable Care Act bars undocumented or recent legal immigrants from receiving financial assistance for health insurance32; thus, many will continue to remain uninsured and dependent on public health services and free clinics for a significant portion of their care. Because these services are associated with government authority, there is the potential that increasing immigration enforcement policies will deter noncitizens from seeking needed care, not only to their detriment but also to the detriment of public health.Currently there is little research examining the impact of recent immigration enforcement policies on the access to and utilization of health care, and there has been a call to better understand the public health impact of current immigration policies and their enforcement.29 Through mixed methods, we explored the effect of local immigration enforcement policies on access to and utilization of health services among immigrant Hispanics/Latinos in North Carolina. We analyzed vital records data to determine whether there were differences in utilization of prenatal services by Hispanic/Latina mothers pre- and postimplementation of section 287(g), and we conducted focus groups and in-depth interviews with Hispanics/Latinos living in counties that had implemented section 287(g) and in “sanctuary” counties, counties in which leaders, including politicians and clergy, have spoken out against the program. 相似文献
95.
Forest Fire Smoke Exposures and Out-of-Hospital Cardiac Arrests in Melbourne,Australia: A Case-Crossover Study 总被引:1,自引:0,他引:1
Martine Dennekamp Lahn D. Straney Bircan Erbas Michael J. Abramson Melita Keywood Karen Smith Malcolm R. Sim Deborah C. Glass Anthony Del Monaco Anjali Haikerwal Andrew M. Tonkin 《Environmental health perspectives》2015,123(10):959-964
Background
Millions of people can potentially be exposed to smoke from forest fires, making this an important public health problem in many countries.Objective
In this study we aimed to measure the association between out-of-hospital cardiac arrest (OHCA) and forest fire smoke exposures in a large city during a severe forest fire season, and estimate the number of excess OHCAs due to the fire smoke.Methods
We investigated the association between particulate matter (PM) and other air pollutants and OHCA using a case-crossover study of adults (≥ 35 years of age) in Melbourne, Australia. Conditional logistic regression models were used to derive estimates of the percent change in the rate of OHCA associated with an interquartile range (IQR) increase in exposure. From July 2006 through June 2007, OHCA data were collected from the Victorian Ambulance Cardiac Arrest Registry. Hourly air pollution concentrations and meteorological data were obtained from a central monitoring site.Results
There were 2,046 OHCAs with presumed cardiac etiology during our study period. Among men during the fire season, greater increases in OHCA were observed with IQR increases in the 48-hr lagged PM with diameter ≤ 2.5 μm (PM2.5) (8.05%; 95% CI: 2.30, 14.13%; IQR = 6.1 μg/m3) or ≤ 10 μm (PM10) (11.1%; 95% CI: 1.55, 21.48%; IQR = 13.7 μg/m3) and carbon monoxide (35.7%; 95% CI: 8.98, 68.92%; IQR = 0.3 ppm). There was no significant association between the rate of OHCA and air pollutants among women. One hundred seventy-four “fire-hours” (i.e., hours in which Melbourne’s air quality was affected by forest fire smoke) were identified during 12 days of the 2006/2007 fire season, and 23.9 (95% CI: 3.1, 40.2) excess OHCAs were estimated to occur due to elevations in PM2.5 during these fire-hours.Conclusions
This study found an association between exposure to forest fire smoke and an increase in the rate of OHCA. These findings have implications for public health messages to raise community awareness and for planning of emergency services during forest fire seasons.Citation
Dennekamp M, Straney LD, Erbas B, Abramson MJ, Keywood M, Smith K, Sim MR, Glass DC, Del Monaco A, Haikerwal A, Tonkin AM. 2015. Forest fire smoke exposures and out-of-hospital cardiac arrests in Melbourne, Australia: a case-crossover study. Environ Health Perspect 123:959–964; http://dx.doi.org/10.1289/ehp.1408436 相似文献96.
Characterization of in vitro metabolites of cudratricusxanthone A in human liver microsomes 下载免费PDF全文
Juhee Sim Eunhwa Choi Gil‐Saeng Jeong Sangkyu Lee 《Biopharmaceutics & drug disposition》2015,36(5):325-336
Cudratricusxanthone A (CTXA), isolated from the roots of Cudrania tricuspidata, exhibits several biological activities; however, metabolic biotransformation was not investigated. Therefore, metabolites of CTXA were investigated and the major metabolic enzymes engaged in human liver microsomes (HLMs) were characterized using liquid chromatography‐tandem mass spectrometry (LC‐MS/MS). CTXA was incubated with HLMs or human recombinant CYPs and UGTs, and analysed by an LC‐MS/MS equipped electrospray ionization (ESI) to qualify and quantify its metabolites. In total, eight metabolites were identified: M1–M4 were identified as mono‐hydroxylated metabolites during Phase I, and M5–M8 were identified as O‐glucuronidated metabolites during Phase II in HLMs. Moreover, these metabolite structures and a metabolic pathway were identified by elucidation of MSn fragments and formation by human recombinant enzymes. M1 was formed by CYP2D6, and M2–M4 were generated by CYP1A2 and CYP3A4. M5–M8 were mainly formed by UGT1A1, respectively. While investigating the biotransformation of CTXA, eight metabolites of CTXA were identified by CYPs and UGTs; these data will be valuable for understanding the in vivo metabolism of CTXA. Copyright © 2015 John Wiley & Sons, Ltd. 相似文献
97.
98.
Ji-Hyeon Park R. Nandi Jae-Kwan Sim Dae-Young Um San Kang Jin-Soo Kim Cheul-Ro Lee 《RSC advances》2018,8(37):20585
III-Nitride nanowires are currently considered as next generation photovoltaic materials due to their excellent physical properties together with reduced dislocation densities, increased surface area and thus enhanced light absorption and direct path for carrier transport. Here, we investigate the photovoltaic characteristics of a solar cell fabricated from a novel hybrid nanostructure comprising uniaxial and coaxial InGaN/GaN multi-quantum wells (MQWs) along with an InGaN nano-cap layer. Various characterization methods were employed to study the optical and structural properties of the hybrid nanostructure. Transmission electron microscopy images revealed the hybrid nanostructure consists of distinct uniaxial and coaxial InGaN/GaN MQWs along with the InGaN nano-cap layer. The InGaN/GaN MQW architectures have a significant effect on the performance of the photovoltaic device. The solar cell fabricated with the hybrid nanostructure exhibits superior photovoltaic performance compared to the uniaxial as well as the coaxial InGaN/GaN nanowire MQW structures. The improved photovoltaic characteristic is primarily attributed to the considerably larger InGaN active area grown in the hybrid nanostructure. A conversion efficiency of 1.16% along with a fill factor of 70% was obtained for the device fabricated with the hybrid nanostructure. This study provides an experimental demonstration of the improvement of III-nitride nanowire based solar cells incorporating uniaxial and coaxial InGaN/GaN MQWs.Solar cells fabricated with hybrid nanowires comprising InGaN/GaN uniaxial and coaxial multi-quantum wells with an InGaN nano-cap layer. 相似文献
99.
Age-related physiologic changes together with high prevalence of chronic illness and the use of multiple medications predispose older adults to syncope. The causes of many of these patients' syncope are unexplained and most remained symptomatic. A thoughtful diagnostic strategy is essential to pinpoint the cause in each patient. The initial assessment includes a comprehensive medical history, preferably with an eye witness account, and a thorough physical examination. The decision for further diagnostic tests often depends on whether there is evidence of underlying structural heart disease. In the absence of heart disease, tilt table testing and the related autonomic function testing are usually most productive. Various cardiac studies will be more appropriate for those with suspected structural heart disease. A cause of syncope can only be concluded if there is a sufficiently strong correlation between syncopal symptoms and the detected abnormalities on investigations. A strategic evaluation of syncope of the elderly subjects should allow a correct diagnosis and appropriate management. 相似文献
100.