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1.
Biochar is a versatile carbon-rich organic material originating from pyrolyzed biomass residues that possess the potential to stabilize organic carbon in the soil, improve soil fertility and water retention, and enhance plant growth. For the utilization of biochar as a soil conditioner, the mutual interconnection of the physicochemical properties of biochar with the production conditions used during the pyrolysis (temperature, heating rate, residence time) and the role of the origin of used biomass seem to be crucial. The aim of the research was focused on a comparison of the properties of biochar samples (originated from oat brans, mixed woodcut, corn residues and commercial compost) produced at different temperatures (400–700 °C) and different residence times (10 and 60 min). The results indicated similar structural features of produced biochar samples; nevertheless, the original biomass showed differences in physicochemical properties. The morphological and structural analysis showed well-developed aromatic porous structures for biochar samples originated from oat brans, mixed woodcut and corn residues. The higher pyrolysis temperature resulted in lower yields; however, it provided products with higher content of organic carbon and a more developed surface area. The lignocellulose biomass with higher contents of lignin is an attractive feedstock material for the production of biochar with potential agricultural applications.  相似文献   
2.
About 15–20% of hospital inpatients are catheterized, and it has been estimated that in an average sized hospital 10–15 patients will die each year from catheter‐related sepsis. Reducing catheterization rates or indwell times has been shown to reduce associated sepsis. This study examined patient experience of catheterization; the rationale for the study was to broaden understanding of catheter impact as part of a wider quality improvement agenda. Fifty patients completed a detailed catheter‐experience patient questionnaire. The patients were all inpatients from 17 wards across a range of specialties. Data were sought on demographics, catheter status, experience and their knowledge of and involvement in the catheter care. Fifty percent gender split. Median catheter time was 5 d (range 2 h to long term). Median age 72 years (range 22–92). Thirty‐four percent (n = 17) of patients did not have the process and options discussed before catheterization. Eighteen percent did not know why they were catheterized. Patients experienced leaking (32%), ‘pain’ (26%), inconvenience (26%), embarrassment (24%), blocking (24%) with 8% finding their catheters ‘restrictive’. Fourteen percent felt they could have coped without the catheter. Urinary catheters have a profound and often negative effect on the inpatient experience. This information can help support and empower colleagues to push for less urinary catheter use in the non‐urological inpatient population and start to better understand the patient experience.  相似文献   
3.
Next-generation sequencing has revealed novel recurrent mutations in chronic lymphocytic leukemia, particularly in patients with aggressive disease. Here, we explored targeted re-sequencing as a novel strategy to assess the mutation status of genes with prognostic potential. To this end, we utilized HaloPlex targeted enrichment technology and designed a panel including nine genes: ATM, BIRC3, MYD88, NOTCH1, SF3B1 and TP53, which have been linked to the prognosis of chronic lymphocytic leukemia, and KLHL6, POT1 and XPO1, which are less characterized but were found to be recurrently mutated in various sequencing studies. A total of 188 chronic lymphocytic leukemia patients with poor prognostic features (unmutated IGHV, n=137; IGHV3-21 subset #2, n=51) were sequenced on the HiSeq 2000 and data were analyzed using well-established bioinformatics tools. Using a conservative cutoff of 10% for the mutant allele, we found that 114/180 (63%) patients carried at least one mutation, with mutations in ATM, BIRC3, NOTCH1, SF3B1 and TP53 accounting for 149/177 (84%) of all mutations. We selected 155 mutations for Sanger validation (variant allele frequency, 10–99%) and 93% (144/155) of mutations were confirmed; notably, all 11 discordant variants had a variant allele frequency between 11–27%, hence at the detection limit of conventional Sanger sequencing. Technical precision was assessed by repeating the entire HaloPlex procedure for 63 patients; concordance was found for 77/82 (94%) mutations. In summary, this study demonstrates that targeted next-generation sequencing is an accurate and reproducible technique potentially suitable for routine screening, eventually as a stand-alone test without the need for confirmation by Sanger sequencing.  相似文献   
4.
The significance of chromosomal translocations (CTRAs) and karyotype complexity (KC) in chronic lymphocytic leukemia (CLL) remains uncertain. To gain insight into these issues, we evaluated a series of 1001 CLL cases with reliable classic cytogenetic data obtained within 6 months from diagnosis before any treatment. Overall, 320 cases were found to carry ≥1 CTRAs. The most frequent chromosome breakpoints were 13q, followed by 14q, 18q, 17q, and 17p; notably, CTRAs involving chromosome 13q showed a wide spectrum of translocation partners. KC (≥3 aberrations) was detected in 157 cases and significantly (P < 0.005) associated with unmutated IGHV genes and aberrations of chromosome 17p. Furthermore, it was identified as an independent prognostic factor for shorter time‐to‐first‐treatment. CTRAs were assigned to two categories (i) CTRAs present in the context of KC, often with involvement of chromosome 17p aberrations, occurring mostly in CLL with unmutated IGHV genes; in such cases, we found that KC rather than the presence of CTRAs per se negatively impacts on survival; (ii) CTRAs in cases without KC, having limited if any impact on survival. On this evidence, we propose that all CTRAs in CLL are not equivalent but rather develop by different processes and are associated with distinct clonal behavior. Am. J. Hematol. 89:249–255, 2014. © 2013 Wiley Periodicals, Inc.  相似文献   
5.
Alkali-activated systems (AAS) represent an ecologically and economically sustainable inorganic binder as an alternative to ordinary Portland cement (OPC). One of the main benefits of AAS is their durability in aggressive environments, which can be equal or even better than that of OPC. In this paper, the influence of the type of alkaline activator in alkali-activated blast furnace slag (AAS) in terms of resistance to sulfur dioxide corrosion was investigated. The durability testing process was based on the CSN EN ISO 3231 standard and simultaneously compared with mortar samples prepared by using Blastfurnace cement CEM III/A 32.5R. The degradation progress was evaluated by employing several different methods such as observing the compressive strength development, weight change evaluation, non-destructive testing methods like ultrasound or impact echo technique, or visual phenolphthalein technique. Subsequently, fundamental characterization of samples by the XRD method was performed during the degradation test. The obtained results indicate that none of the testing methods used could be prioritized over others to determine the resistance of AAS against the action of sulfur dioxide. For this reason, the durability testing of AAS remains an issue, and the development of specific standards considering the behavior of AAS seems necessary.  相似文献   
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7.

Rationale and objectives

General practitioners (GPs) play an important role in management of patients at risk of osteoporosis (OP). The objectives were to assess (1) knowledge about OP and use of OP clinical guideline in comparison with other information sources and (2) association between the use of individual information sources and knowledge and self-reported quality of care among GPs.

Methods

Survey among random sample of Czech GPs was performed to find out their attitudes and role in OP management. The return rate of the postal questionnaire was 38% (525 respondents). Quality of care was assessed using three indicators: suspicion on OP, referral to the specialist and initial check-up.

Results

Respondents (median age 52 years, 59% women) had a very good knowledge of several risk factors, while others, namely low body mass index, history of hip fracture in mother and smoking were perceived as risk factors by only 40%, 45% and 55% of respondents, respectively. 10% of GPs stated the correct answer regarding daily calcium intake recommended for postmenopausal women. The OP guideline was considered accessible by 83% of respondents and used repeatedly by 54%. Use of the guideline correlated positively with knowledge score (P < 0.001), while use of each individual other source of information did not. Use of the guideline correlated with all three indicators of quality of care. Use of each other information source correlated only with a maximum of two indicators.

Conclusion

We identified areas of insufficient knowledge that should be targeted in educational activities for GPs. It is recommended to further motivate GPs to use their clinical guidelines regularly.  相似文献   
8.

Study Objective

To investigate ethnic differences for moderate-to-severe endometriosis.

Design

Analysis of a prospective registry (Canadian Task Force classification II-2).

Setting

Tertiary referral center.

Patients

A total of 1594 women with pelvic pain and/or endometriosis.

Interventions

None

Measurements and Main Results

On logistic regression, adjusting for potential confounders, East/South East Asians were 8.3 times more likely than whites to have a previous diagnosis of stage III/IV endometriosis before referral (adjusted odds ratio [aOR], 8.33; 95% confidence interval [CI], 3.74–18.57), 2.7 times more likely to have a palpable nodule (aOR, 2.66; 95% CI, 1.57–4.52), 4.1 times more likely to have an endometrioma on ultrasound (aOR, 4.10; 95% CI, 2.68–6.26), and 10.9 times more likely to have stage III/IV endometriosis at the time of surgery at our center (aOR, 10.87; 95% CI, 4.34–27.21).

Conclusion

Moderate-to-severe endometriosis was more common in women with East or South East Asian ethnicity in our tertiary referral center.  This could be explained by East/South East Asians with minimal to mild disease being less likely to seek care or genetic/environmental differences that increase the risk of more severe disease among East/South East Asians. (ClinicalTrials.gov, NCT02911090.)  相似文献   
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