596 research outputs found
Correction to: Sol–Gel Synthesis of High-Density Zeolitic Imidazolate Framework Monoliths via Ligand Assisted Methods: Exceptional Porosity, Hydrophobicity, and Applications in Vapor Adsorption (Advanced Functional Materials, (2021), 31, 5, (2008357), 10.1002/adfm.202008357)
In the original published version of this article, the bulk densities of the powder ZIF-8 and ZIF-67 were quoted as 0.96 g/cm3 and 0.94 g/cm3 respectively. However, the values for the powder samples’ true density were quoted in error. The correct bulk densities, used for calculating volume-relative capacities and surface areas, were 0.39 g/cm3 and 0.38 g/cm3 for ZIF-8 and ZIF-67, respectively. As this affects the calculated ‘volume-relative’ quantities, corrected tables and graphs are included below. The authors apologise for any inconvenience or confusion this error may have caused. Corrected tables Corrected values will be written and underlined in red. 1 Table Physical characteristics of ZIF samples. Surface areas and porosities expressed in mass-relative and volume-relative terms. Tpycometry = 25 °C. Tgas adsorption = -196 °C (Table presented.) a) Volume-relative quantities calculated by multiplying bulk density by mass-relative quantity b) Due to lack of micropores within sample, micropore volume could not be determined. 3 Table Summary of low concentration dynamic adsorption experiments. All measurements carried out at a toluene partial pressure of 0.00026, and a temperature of 25 °C (Table presented.) a) Calculated by dividing capacity when toluene is first detected by the capacity when the inlet and outlet concentrations of toluene are equal. 4 Table Estimated mass-relative and volume-relative toluene vapour capture productivities for adsorbents. Calculated using gravimetric toluene adsorption data at a partial pressure of 0.1 and a temperature of 25 °C (Table presented.) a) Time taken to reach a mass gradient value of 0.00075% dry mass per minute. Corrected main text figures 6 Figure (Figure presented.) Co-sorption volume-relative toluene vapour capacities as a function of process humidity, for zinc (left) and cobalt (right) ZIF samples. Partial pressure of toluene in all measurements, P/P0 = 0.005, while water vapour partial pressure varied. All measurements carried out at 25 °C. Corrected supplementary information figures S4 Figure (Figure presented.) Volume-relative nitrogen adsorption isotherms for zinc (left) and cobalt (right) samples. Temperature in all experiments is -196 °C. S5 Figure (Figure presented.) Volume-relative adsorption isotherms for zinc (left) and cobalt (right) samples: water (top), toluene (middle), methanol (bottom). Temperature in all experiments is 25 °C
Docetaxel-carboplatin as first line chemotherapy for epithelial ovarian cancer
A prospective, non-randomized, multicentre, open, dose-finding study of a carboplatin-docetaxel (C-D) combination as first-line chemotherapy in FIGO stage Ic–IV epithelial ovarian cancer. C-D was given 3-weekly for 6 planned cycles, with a 3-day prophylactic dexamethasone regimen (8 mg b.i.d.). 139 eligible patients (Pts) (median age 56 years, range 28–85) were given a total of 750 cycles of chemotherapy in 5 cohorts: Co1, 32 pts, 169 cycles (C at AUC 5 + D 60 mg/m2); Co2, 22 pts, 122 cycles (5 + 75), Co3, 29 pts, 156 cycles (6 + 75), Co4, 27 pts, 146 cycles (7 + 75), Co5, 30 pts, 157 cycles (6 + 85). 110 patients (79%) completed 6 cycles; 17 (12%) stopped due to toxicity. 104 patients (75%) had CTC grade IV neutropenia, and 5 patients (4%) had this associated with fever. There were 2 probable treatment-related deaths. Only 8 patients (6%) experienced grade II–III neurotoxicity (all sensory; no motor > grade I). The maximum tolerated dose was reached in cohorts 4 and 5, and the dose limiting toxicities were myelosuppression and diarrhoea. The overall response rate for the study was 66% (49/74); CA125 response was 75% (70/93). Median progression-free survival was 16.6 months (95% CI 13.3–19.1). Recommended doses are carboplatin AUC 5 (via51 Cr EDTA) or AUC 6 (if calculated) plus docetaxel 75 mg/m2. A randomized trial comparing this regimen with carboplatin-paclitaxel has just completed recruitment. © 2001 Cancer Research Campaign http://www.bjcancer.co
Theory of current-driven motion of Skyrmions and spirals in helical magnets
We study theoretically the dynamics of the spin textures, i.e., Skyrmion
crystal (SkX) and spiral structure (SS), in two-dimensional helical magnets
under external current. By numerically solving the Landau-Lifshitz-Gilbert
equation, it is found that (i) the critical current density of the motion is
much lower for SkX compared with SS in agreement with the recent experiment,
(ii) there is no intrinsic pinning effect for SkX and the deformation of the
internal structure of Skyrmion reduces the pinning effect dramatically, (iii)
the Bragg intensity of SkX shows strong time-dependence as can be observed by
neutron scattering experiment.Comment: 4 pages, 3 figure
Relationship Between Non-Hodgkin's Lymphoma and Blood Levels of Epstein-Barr Virus in Children in North-Western Tanzania: A Case Control Study.
Non-Hodgkin's Lymphomas (NHL) are common in African children, with endemic Burkitt's lymphoma (BL) being the most common subtype. While the role of Epstein-Barr Virus (EBV) in endemic BL is known, no data are available about clinical presentations of NHL subtypes and their relationship to Human Immunodeficiency Virus (HIV) infection and Epstein Barr Virus (EBV) load in peripheral blood of children in north-western, Tanzania. A matched case control study of NHL subtypes was performed in children under 15 years of age and their respective controls admitted to Bugando Medical Centre, Sengerema and Shirati district designated hospitals in north-western, Tanzania, between September 2010 and April 2011. Peripheral blood samples were collected on Whatman 903 filter papers and EBV DNA levels were estimated by multiplex real-time PCR. Clinical and laboratory data were collected using a structured data collection tool and analysed using chi-square, Fisher and Wilcoxon rank sum tests where appropriate. The association between NHL and detection of EBV in peripheral blood was assessed using conditional logistic regression model and presented as odds ratios (OR) and 95% confidence intervals (CI). A total of 35 NHL cases and 70 controls matched for age and sex were enrolled. Of NHLs, 32 had BL with equal distribution between jaw and abdominal tumour, 2 had large B cell lymphoma (DLBCL) and 1 had NHL-not otherwise specified (NHL-NOS). Central nervous system (CNS) presentation occurred only in 1 BL patient; 19 NHLs had stage I and II of disease. Only 1 NHL was found to be HIV-seropositive. Twenty-one of 35 (60%) NHL and 21 of 70 (30%) controls had detectable EBV in peripheral blood (OR = 4.77, 95% CI 1.71 - 13.33, p = 0.003). In addition, levels of EBV in blood were significantly higher in NHL cases than in controls (p = 0.024). BL is the most common childhood NHL subtype in north-western Tanzania. NHLs are not associated with HIV infection, but are strongly associated with EBV load in peripheral blood. The findings suggest that high levels of EBV in blood might have diagnostic and prognostic relevance in African children
Emerging breast cancer epidemic: evidence from Africa
Cancer is an increasingly important public health problem in developing countries, including Africa [1]. As public and professional awareness of the cancer problem has grown, so has interest in the pattern of disease presentation, its epidemiology and treatment outcome. To date, however, there has been limited research about breast cancer in Africa. In the absence of systematic population-based cancer registration, most information has come from small clinical and pathology case series and the bias inherent in these types of studies has influenced current understanding of the pattern and characteristics of breast cancer in Africa. In this communication, we review the evidence for an emerging epidemic of breast cancer in Africa, its risk factors and likely future course. We conclude that, despite limited data, rising incidence of breast cancer is being driven by increasing life expectancy, improved control of infectious diseases, and changing lifestyle, diet, physical activity and obstetric practices. We also review current beliefs about hormone receptor subtypes of breast cancer in Africa and suggest that this is probably not systematically different from the pattern in other populations after adjusting for factors such as age and that the reported differences are related to poor tissue handling and laboratory processing practices
Increasing uptake of colorectal cancer screening in Korea: a population-based study
<p>Abstract</p> <p>Background</p> <p>Colorectal cancer (CRC) screening rates are low in most Asian countries and remain largely unknown. This study examined trends in CRC screening rates after the introduction of the Korean National Cancer Screening Programme (NCSP) and determined the factors associated with uptake of CRC screening by test modality over time.</p> <p>Methods</p> <p>An annual population-based survey conducted through nationally representative random sampling from 2005-2008. In total, 3,699 participants from the 2005-2008 surveys were selected as study subjects. Face-to-face interviews were performed to assess the utilization rate of CRC screening by each screening modality.</p> <p>Results</p> <p>Overall, CRC screening within the recommended time interval increased significantly from 22.9% in 2005 to 36.6% in 2008 (<it>p </it>< 0.001). The proportion of subjects receiving a fecal occult blood test (FOBT) test within the previous year increased significantly from 7.2% in 2005 to 21.3% in 2008 (<it>p </it>< 0.001). Increases in FOBT testing were highest among those who had a lower income status (relative difference = 511.9%) and women (relative difference = 266.1%). Endoscopy use also increased from 18.0% in 2005 to 20.5% in 2008, albeit not significant. Overall, those who were male, non-smokers, 60-69 years old, and had a higher income status were more likely to have undergone up-to-date endoscopy and CRC screening.</p> <p>Conclusions</p> <p>This study revealed a substantial increase in up-to-date CRC screening in the general population from 2005 to 2008. However, more than half of adults in Korea are still not up-to-date with their CRC tests. It will be important to continue to investigate factors associated with up-to-date CRC screening by each modality.</p
Update: cohort mortality study of workers highly exposed to polychlorinated biphenyls (PCBs) during the manufacture of electrical capacitors, 1940-1998
BACKGROUND: The National Institute for Occupational Safety and Health previously reported mortality for a cohort of workers considered highly exposed to polychlorinated biphenyls (PCBs) between 1939 and 1977 at two electrical capacitor manufacturing plants. The current study updated vital status, examined liver and rectal cancer mortality previously reported in excess in this cohort and evaluated mortality from non-Hodgkin's lymphoma (NHL) and cancers of the stomach, intestine, breast, prostate, skin (melanoma) and brain reported to be in excess in other cohort and case-control studies of PCB-exposed persons. METHODS: Mortality was updated through 1998 for 2572 workers. Age-, gender-, race- and calendar year-adjusted standardized mortality ratios (SMRs) and 95% confidence intervals (CI) were calculated using U.S., state and county referent rates. SMRs using U.S. referent rates are reported. Duration of employment was used as a surrogate for exposure. RESULTS: Consistent with the previous follow-up, mortality from biliary passage, liver and gall bladder cancer was significantly elevated (11 deaths, SMR 2.11, CI 1.05 – 3.77), but mortality from rectal cancer was not (6 deaths, SMR 1.47, CI 0.54 – 3.21). Among women, mortality from intestinal cancer (24 deaths, SMR 1.89, CI 1.21 – 2.82) and from "other diseases of the nervous system and sense organs", which include Parkinson's disease and amyotrophic lateral sclerosis, (15 deaths, SMR 2.07, CI 1.16 – 3.42) were elevated. There were four ALS deaths, all women (SMR 4.35, CI 1.19–11.14). Mortality was elevated for myeloma (7 deaths, SMR 2.11, CI 0.84 – 4.34), particularly among workers employed 10 years or more (5 deaths, SMR 2.80, CI 0.91 – 6.54). No linear associations between mortality and duration of employment were observed for the cancers of interest. CONCLUSION: This update found that the earlier reported excess in this cohort for biliary, liver and gall bladder cancer persisted with longer follow-up. Excess mortality for intestinal cancer among women was elevated across categories of duration of employment; myeloma mortality was highest among those working 10 years or more. The small numbers of deaths from liver and intestinal cancers, myeloma and nervous system diseases coupled with the lack of an exposure-response relationship with duration of employment preclude drawing definitive conclusions regarding PCB exposure and these causes of death
Faecal occult blood screening and reduction of colorectal cancer mortality: a case-control study
To estimate the efficacy of screening on colorectal cancer mortality, a population-based case–control study was conducted in well-defined areas of Burgundy (France). Screening by faecal occult blood test prior to diagnosis in cases born between 1914 and 1943 and who died of colorectal cancer diagnosed in 1988–94 was compared with screening in controls matched with the case for age, sex and place of residence. Cases were less likely to have been screened than controls, with an odds ratio (OR) of 0.67 [95% confidence interval (CI) 0.48–0.94]. The negative overall association did not differ by gender or by anatomical location. The odds ratio of death from colorectal cancer was 0.64 (95% CI 0.46–0.91) for those screened within 3 years of case diagnosis compared with those not screened. It was 1.14 (95% CI 0.50–2.63) for those screened more than 3 years before case diagnosis. There was a negative association between the risk of death from colorectal cancer and the number of participations in the screening campaigns. The inverse association between screening for faecal occult blood and fatal colorectal cancer suggests that screening can reduce colorectal cancer mortality. This report further supports recommendations for population-based mass screening with faecal occult blood test. © 1999 Cancer Research Campaig
Using Routinely Collected Administrative Data in Public Health Research: Geocoding Alcohol Outlet Data
We describe our process of geocoding alcohol outlets to create a national longitudinal exposure dataset for Wales, United Kingdom from 2006 to 2011. We investigated variation in the availability of data items and the quality of alcohol outlet addresses held within unitary authorities. We used a standard geocoding method augmented with a manual matching procedure to achieve a fully spatially referenced dataset. We found higher quality addresses are held for outlets based in urban areas, resulting in the automatic geocoding of 68 % of urban outlets, compared to 48 % in rural areas. Missing postcodes and a lack of address structure contributed to a lower geocoding proportion. An urban rural bias was removed with the development of a manual matching procedure. Only one-half of the unitary authorities provided data on on/off sales and opening times, which are important availability factors. The resulting outlet dataset is suitable for contributing to the evidence-base of alcohol availability and alcohol-related harm. Local government should be encouraged to use standardised data fields, including addresses, to enable accurate geocoding of alcohol outlets and facilitate research that aims to prevent alcohol-related harm. Standardising data collection would enable efficient secondary data reuse using record linkage techniques, allowing the retrospective creation and evaluation of population-based natural experiments to provide evidence for policy and practice
- …