Abstract
The electronic instabilities in CsV
3
Sb
5
are believed to originate from the V 3
d
-electrons on the kagome plane, however the role of Sb 5
p
-electrons for 3-dimensional orders is largely ...unexplored. Here, using resonant tender X-ray scattering and high-pressure X-ray scattering, we report a rare realization of conjoined charge density waves (CDWs) in CsV
3
Sb
5
, where a 2 × 2 × 1 CDW in the kagome sublattice and a Sb 5
p
-electron assisted 2 × 2 × 2 CDW coexist. At ambient pressure, we discover a resonant enhancement on Sb
L
1
-edge (2
s
→5
p
) at the 2 × 2 × 2 CDW wavevectors. The resonance, however, is absent at the 2 × 2 × 1 CDW wavevectors. Applying hydrostatic pressure, CDW transition temperatures are separated, where the 2 × 2 × 2 CDW emerges 4 K above the 2 × 2 × 1 CDW at 1 GPa. These observations demonstrate that symmetry-breaking phases in CsV
3
Sb
5
go beyond the minimal framework of kagome electronic bands near van Hove filling.
Resistance to triazoles was recently reported in Aspergillus fumigatus isolates cultured from patients with invasive aspergillosis. The prevalence of azole resistance in A. fumigatus is unknown. We ...investigated the prevalence and spread of azole resistance using our culture collection that contained A. fumigatus isolates collected between 1994 and 2007.
We investigated the prevalence of itraconazole (ITZ) resistance in 1,912 clinical A. fumigatus isolates collected from 1,219 patients in our University Medical Centre over a 14-y period. The spread of resistance was investigated by analyzing 147 A. fumigatus isolates from 101 patients, from 28 other medical centres in The Netherlands and 317 isolates from six other countries. The isolates were characterized using phenotypic and molecular methods. The electronic patient files were used to determine the underlying conditions of the patients and the presence of invasive aspergillosis. ITZ-resistant isolates were found in 32 of 1,219 patients. All cases were observed after 1999 with an annual prevalence of 1.7% to 6%. The ITZ-resistant isolates also showed elevated minimum inhibitory concentrations of voriconazole, ravuconazole, and posaconazole. A substitution of leucine 98 for histidine in the cyp51A gene, together with two copies of a 34-bp sequence in tandem in the gene promoter (TR/L98H), was found to be the dominant resistance mechanism. Microsatellite analysis indicated that the ITZ-resistant isolates were genetically distinct but clustered. The ITZ-sensitive isolates were not more likely to be responsible for invasive aspergillosis than the ITZ-resistant isolates. ITZ resistance was found in isolates from 13 patients (12.8%) from nine other medical centres in The Netherlands, of which 69% harboured the TR/L98H substitution, and in six isolates originating from four other countries.
Azole resistance has emerged in A. fumigatus and might be more prevalent than currently acknowledged. The presence of a dominant resistance mechanism in clinical isolates suggests that isolates with this mechanism are spreading in our environment.
Aims/hypothesis
While it is well known that diet-induced obesity causes insulin resistance, the precise mechanisms underpinning the initiation of insulin resistance are unclear. To determine factors ...that may cause insulin resistance, we have performed a detailed time-course study in mice fed a high-fat diet (HFD).
Methods
C57Bl/6 mice were fed chow or an HFD from 3 days to 16 weeks and glucose tolerance and tissue-specific insulin action were determined. Tissue lipid profiles were analysed by mass spectrometry and inflammatory markers were measured in adipose tissue, liver and skeletal muscle.
Results
Glucose intolerance developed within 3 days of the HFD and did not deteriorate further in the period to 12 weeks. Whole-body insulin resistance, measured by hyperinsulinaemic–euglycaemic clamp, was detected after 1 week of HFD and was due to hepatic insulin resistance. Adipose tissue was insulin resistant after 1 week, while skeletal muscle displayed insulin resistance at 3 weeks, coinciding with a defect in glucose disposal. Interestingly, no further deterioration in insulin sensitivity was observed in any tissue after this initial defect. Diacylglycerol content was increased in liver and muscle when insulin resistance first developed, while the onset of insulin resistance in adipose tissue was associated with increases in ceramide and sphingomyelin. Adipose tissue inflammation was only detected at 16 weeks of HFD and did not correlate with the induction of insulin resistance.
Conclusions/interpretation
HFD-induced whole-body insulin resistance is initiated by impaired hepatic insulin action and exacerbated by skeletal muscle insulin resistance and is associated with the accumulation of specific bioactive lipid species.
Summary Background Chronic kidney disease is characterised by low estimated glomerular filtration rate (eGFR) and high albuminuria, and is associated with adverse outcomes. Whether these risks are ...modified by diabetes is unknown. Methods We did a meta-analysis of studies selected according to Chronic Kidney Disease Prognosis Consortium criteria. Data transfer and analyses were done between March, 2011, and June, 2012. We used Cox proportional hazards models to estimate the hazard ratios (HR) of mortality and end-stage renal disease (ESRD) associated with eGFR and albuminuria in individuals with and without diabetes. Findings We analysed data for 1 024 977 participants (128 505 with diabetes) from 30 general population and high-risk cardiovascular cohorts and 13 chronic kidney disease cohorts. In the combined general population and high-risk cohorts with data for all-cause mortality, 75 306 deaths occurred during a mean follow-up of 8·5 years (SD 5·0). In the 23 studies with data for cardiovascular mortality, 21 237 deaths occurred from cardiovascular disease during a mean follow-up of 9·2 years (SD 4·9). In the general and high-risk cohorts, mortality risks were 1·2–1·9 times higher for participants with diabetes than for those without diabetes across the ranges of eGFR and albumin-to-creatinine ratio (ACR). With fixed eGFR and ACR reference points in the diabetes and no diabetes groups, HR of mortality outcomes according to lower eGFR and higher ACR were much the same in participants with and without diabetes (eg, for all-cause mortality at eGFR 45 mL/min per 1·73 m2 vs 95 mL/min per 1·73 m2 , HR 1·35; 95% CI 1·18–1·55; vs 1·33; 1·19–1·48 and at ACR 30 mg/g vs 5 mg/g, 1·50; 1·35–1·65 vs 1·52; 1·38–1·67). The overall interactions were not significant. We identified much the same findings for ESRD in the chronic kidney disease cohorts. Interpretation Despite higher risks for mortality and ESRD in diabetes, the relative risks of these outcomes by eGFR and ACR are much the same irrespective of the presence or absence of diabetes, emphasising the importance of kidney disease as a predictor of clinical outcomes. Funding US National Kidney Foundation.
Objective
To compare the efficacy of two types of progestogen therapy for preventing preterm birth (PTB) and to review the relevant literature.
Design
A multicentre, randomised, open‐label, ...equivalence trial and a meta‐analysis.
Setting
Tertiary referral hospitals in South Korea.
Population
Pregnant women with a history of spontaneous PTB or short cervical length (<25 mm).
Methods
Eligible women were screened and randomised at 16‒22 weeks of gestation to receive either 200 mg of vaginal micronised progesterone daily (vaginal group) or an intramuscular injection of 250 mg 17α‐hydroxyprogesterone caproate weekly (IM group). Stratified randomisation was carried out according to participating centres and indications for progestogen therapy. This trial was registered at ClinicalTrials.gov (NCT02304237).
Main outcome measure
Preterm birth (PTB) before 37 weeks of gestation.
Results
A total of 266 women were randomly assigned and a total of 247 women (119 and 128 women in the vaginal and IM groups, respectively) were available for the intention‐to‐treat analysis. Risks of PTB before 37 weeks of gestation did not significantly differ between the two groups (22.7 versus 25.8%, P = 0.571). The difference in PTB risk between the two groups was 3.1% (95% CI −7.6 to 13.8%), which was within the equivalence margin of 15%. The meta‐analysis results showed no significant differences in the risk of PTB between the vaginal and IM progestogen treatments.
Conclusion
Compared with vaginal progesterone, treatment with intramuscular progestin might increase the risk of PTB before 37 weeks of gestation by as much as 13.8%, or reduce the risk by as much as 7.6%, in women with a history of spontaneous PTB or with short cervical length.
Tweetable
Vaginal and intramuscular progestogen showed equivalent efficacy for preventing preterm birth before 37 weeks of gestation.
Tweetable
Vaginal and intramuscular progestogen showed equivalent efficacy for preventing preterm birth before 37 weeks of gestation.
•State-of-the-art of MD hybrids with a focus on energy efficiency enhancement are presented.•Reduction of specific energy consumption, energy optimization and thermodynamic limits are ...discussed.•Major technology advances of the MD process are highlighted.•Pros and cons of each hybrid process are discussed and perspectives are emphasized.•Current trends and perspectives of MD hybrid systems are discussed.
With an ever-increasing demand in energy, constrained by strict environmental regulations, process development faces stringent design requirements further limited by intrinsic properties of inherent materials. Process hybridization is now considered as an improvement path to several limitations. Complementarity between processes is the essence of the hybridization concept, with the ultimate goal to design more eco-friendly, energy efficient process combinations delivering higher throughputs and boosting the thermodynamic limits of the existing mature technologies. Market size of membrane-based separation processes, widely used in desalination, water treatment and purification, is forecasted to grow significantly in the next decades. While desalination market is mainly shared between thermal processes and reverse osmosis (RO), advanced water treatment and purification rely mostly on membrane technology. Among the large span of available techniques stands membrane distillation (MD), to which a tremendous research effort has been dedicated during the last two decades. Although praised for its numerous advantages, this thermally-driven separation process still cannot withstand large production rates while maintaining energy efficiency. Hybridization of MD with existing technologies and other emerging processes is therefore at the leading edge. This literature review presents the state-of-the-art MD hybrids with different separation processes including RO, pressure retarded osmosis, forward osmosis, mechanical vapor compression, electrocoagulation, electrodialysis, multi-stage flash, multi-effect distillation, crystallization and adsorption with a focus on water production and energy efficiency enhancement. Each of these processes has advantages at the cost of more or less severe drawbacks and its association to MD offers improvement opportunities. Each variant is thoroughly reviewed with major contributions and knowledge gaps highlighted. Perspectives and recommendations are emphasized in each case. Latest developments in MD and its energy consumption and optimization are also reported.
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