Objective: The epidemiological evidence for the association between sleep duration and obesity in the elderly is inconsistent and has not been investigated with objective measures. Furthermore, the ...role of sleep fragmentation in this relationship is unknown. Our aim was to investigate the association of sleep measures with body mass index (BMI) and obesity in a normal elderly population. Design: Cross-sectional study. Subjects: A total of 983 community-dwelling elderly (mean age 68.46.9 years, range, 57-97). Measurements: Weight and height were measured, and sleep duration and fragmentation were assessed with on average six nights of actigraphy. Results: A quadratic model adequately described the association between continuous measures of sleep duration and BMI. Actigraphic sleep duration had a significant U-shaped relationship with BMI ( of quadratic term=0.30, 95% confidence interval (CI): 0.08, 0.52). Both short sleepers (<5 h: OR, 2.76 (95% CI: 1.38, 5.49), 5 to <6 h: OR, 1.97 (95% CI: 1.26, 3.08)) and long sleepers (8 h: OR, 2.93 (95% CI: 1.39, 6.16)) were more likely to be obese, compared to participants who slept 7 to <8 h. BMI increased with 0.59 kg m-2 per standard deviation of sleep fragmentation (95% CI: 0.34, 0.84). After adjustment for sleep fragmentation, the association between short sleep and obesity was no longer significant. Exclusion of participants with probable sleep apnea only marginally changed these associations. Self-reported habitual sleep duration was not associated with BMI or obesity. Conclusions: Sleep duration, as measured with actigraphy, had a U-shaped relationship with BMI and obesity in an elderly population. A highly fragmented sleep is associated with a higher BMI and a higher risk of obesity, and may explain why short sleep is related to obesity. To preclude bias that can be introduced by self-report measures of sleep duration, using multiple measures of sleep parameters is recommended in future research.
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Anion exchange membranes (AEMS) are particularly prone to fouling when employed to desalinate polymer flooding produced water (PFPW), an abundant sub-product from the oil and gas ...industry. The formation of fouling on an AEM will be affected by the composition of the solution, which includes various dissolved salts, partially hydrolyzed polyacrylamide (HPAM), crude oil, and surfactants.
Electrodialysis experiments were performed to desalinate feed solutions with different compositions, aiming to distinguish between their individual and combined effects. The solutions contained diverse mono- and divalent ions. The analysis included data collected during the desalination and characterization of the fouled AEMs by diverse analytical techniques.
HPAM produced the most severe effects in terms of visible fouling and increase of resistance. This polyelectrolyte fouls the AEM by adsorbing on its surface and by forming a viscous gel layer that hampers the replenishment of ions from the bulk solution. Ca and Mg have a large influence on the formation of thick HPAM gel layers, while the oily compounds have only a minimal influence acting mainly as a destabilizing agent. The membranes also presented scaling consisting of calcium precipitates. The effects of the gel layer were minimized by applying current reversal and foulant-free solution.
To investigate and explain sex differences in subjective and actigraphic sleep parameters in community-dwelling elderly persons.
Cross-sectional study.
The study was embedded in the Rotterdam Study, ...a population-based study.
Nine hundred fifty-six participants aged 59 to 97 years.
N/A.
Participants wore an actigraph and kept a sleep diary for an average of 6 consecutive nights. Subjective sleep quality was assessed with the Pittsburgh Sleep Quality Index. Unadjusted sex differences in sleep parameters were assessed with t tests. Women reported shorter total sleep time, a less favorable sleep-onset latency, lower sleep efficiency, and worse global sleep quality, as compared with men. When assessed with actigraphy, however, women were found to have longer and less-fragmented sleep than men. Sex differences in diary-reported sleep duration and other subjective sleep parameters were attenuated by adjustment for marital status, the use of sleep medication, and other covariates, but all sex differences remained significant in a multivariate-adjusted model. Sex differences in actigraphic sleep parameters were barely attenuated by multivariate adjustment, although the shorter actigraphically measured sleep duration in men was partly explained by their higher alcohol consumption. Some covariates (eg, sleep medication) had a different relationship with diary-reported or actigraphic total sleep time in men and women.
If assessed by diary or interview, elderly women consistently reported shorter and poorer sleep than elderly men. In contrast, actigraphic sleep measures showed poorer sleep in men. These discrepancies are partly explained by determinants of sleep duration, such as sleep medication use and alcohol consumption.
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Cation exchange membranes (CEMs) are subject to fouling when utilized to desalinate wastewater from the oil and gas industry, hampering their performance. The kind and extent of the ...fouling are most likely dependent on the composition of the stream, which in practical applications can vary significantly.
Fouling experiments were performed on commercial cation exchange membranes, which were used in electrodialysis runs to desalinate solutions of varying composition. The variations included ionic strength, type of ions, amount of viscosifying polyelectrolyte (partially hydrolyzed polyacrylamide), presence of crude oil, and surfactants. Performance parameters, like electric potential and pH, were monitored during the runs, after which the membranes were recovered and analyzed.
Fouling was detected on most CEMs and occurred mainly in the presence of the viscosifying polyelectrolyte. Under normal pH conditions (pH ~ 8), the polyelectrolyte fouled the concentrate side of the CEMs, as expected due to electrophoresis. However, by applying a current in the opposite direction, the polyelectrolyte layer could be removed. Precipitation occurred mostly on the opposite side of the membrane, with different morphology depending on the feed composition.
Frontotemporal lobar degeneration (FTLD) is characterized pathologically by neuronal and glial inclusions of hyperphosphorylated tau or by neuronal cytoplasmic inclusions of TDP43. This study aimed ...at deciphering the molecular mechanisms leading to these distinct pathological subtypes.
To this end, we performed an unbiased mass spectrometry-based proteomic and systems-level analysis of the middle frontal gyrus cortices of FTLD-tau (n = 6), FTLD-TDP (n = 15), and control patients (n = 5). We validated these results in an independent patient cohort (total n = 24).
The middle frontal gyrus cortex proteome was most significantly altered in FTLD-tau compared to controls (294 differentially expressed proteins at FDR = 0.05). The proteomic modifications in FTLD-TDP were more heterogeneous (49 differentially expressed proteins at FDR = 0.1). Weighted co-expression network analysis revealed 17 modules of co-regulated proteins, 13 of which were dysregulated in FTLD-tau. These modules included proteins associated with oxidative phosphorylation, scavenger mechanisms, chromatin regulation, and clathrin-mediated transport in both the frontal and temporal cortex of FTLD-tau. The most strongly dysregulated subnetworks identified cyclin-dependent kinase 5 (CDK5) and polypyrimidine tract-binding protein 1 (PTBP1) as key players in the disease process. Dysregulation of 9 of these modules was confirmed in independent validation data sets of FLTD-tau and control temporal and frontal cortex (total n = 24). Dysregulated modules were primarily associated with changes in astrocyte and endothelial cell protein abundance levels, indicating pathological changes in FTD are not limited to neurons.
Using this innovative workflow and zooming in on the most strongly dysregulated proteins of the identified modules, we were able to identify disease-associated mechanisms in FTLD-tau with high potential as biomarkers and/or therapeutic targets.
Summary
Sleep duration is an important concept in epidemiological studies. It characterizes a night’s sleep or a person’s sleep pattern, and is associated with numerous health outcomes. In most large ...studies, sleep duration is assessed with questionnaires or sleep diaries. As an alternative, actigraphy may be used, as it objectively measures sleep parameters and is feasible in large studies. However, actigraphy and sleep diaries may not measure exactly the same phenomenon. Our study aims to determine disagreement between actigraphic and diary estimates of sleep duration, and to investigate possible determinants of this disagreement. This investigation was embedded in the population‐based Rotterdam Study. The study population consisted of 969 community‐dwelling participants aged 57–97 years. Participants wore an actigraph and kept a sleep diary for, on average, six consecutive nights. Both measures were used to determine total sleep time (TST). In 34% of the participants, the estimated TST in the sleep diaries deviated more than 1 h from actigraphically measured TST. The level of disagreement between diary and actigraphic measures decreased with subjective and actigraphic measures of sleep quality, and increased with male gender, poor cognitive function and functional disability. Actigraphically measured poor sleep was often accompanied by longer subjective estimates of TST, whereas subjectively poor sleepers tended to report shorter TST in their diaries than was measured with actigraphy. We recommend, whenever possible, to use multiple measures of sleep duration, to perform analyses with both, and to examine the consistency of the results over assessment methods.
Little is known about the etiology of childhood acute lymphoblastic leukemia (ALL). The presence of atopic disease has been shown to protect against developing childhood ALL. The aim of this study ...was to examine whether single nucleotide polymorphisms (SNPs) in innate immunity genes previously associated with atopic disease, can elucidate the inverse association between childhood ALL and atopic disease. We studied 525 children, including 192 with childhood ALL, 149 with atopic disease and 184 healthy control subjects. We compared genotype distributions of 29 SNPs in genes of TLR2, TLR4, TLR6, TLR9, TLR10 and CD14 between the three groups and corrected for multiple testing. The genotype distributions of two SNPs in the TLR6 gene, rs5743798 and rs6531666, differed significantly between children with ALL, children with atopic disease and control subjects. Particularly in children with atopic eczema, risk alleles for atopic disease were observed more often than in control subjects, and less often in children with ALL than in control subjects. These findings support the immune surveillance hypothesis as an explanation for the protective association of atopic disease on childhood ALL. Further investigation is warranted to examine in more detail the role of innate immunity in the development of childhood ALL.
Several large studies have shown that both short and long average sleep durations increase the risk of hypertension in adults. We investigated whether sleep duration is also associated with ...hypertension in the elderly. This cross-sectional study was conducted in 5058 participants of the population-based Rotterdam Study, aged 58 to 98 years. Blood pressure was measured at the research center. Hypertension was defined as a systolic blood pressure of ≥160 mm Hg and/or a diastolic blood pressure of ≥100 mm Hg or current use of antihypertensive medication. In all of the participants, sleep duration was assessed by self-report. In a subsample of 975 subjects, it was additionally measured with actigraphy, a validated method that infers wakefulness and sleep from the presence or absence of limb movement. After adjustment for age and gender and additionally for body mass index, smoking, depressive symptoms, sleep medication use, diabetes mellitus, myocardial infarction, and stroke, none of the odds ratios (varying from 0.54; 95% CI0.27 to 1.08; to 1.19; 95% CI0.89 to 1.58) reflected a significant association between sleep duration and hypertension, whether measured by self-report or actigraphy. This study strongly suggests that sleep duration is not associated with hypertension in the elderly.
We present a model of the distribution of noise annoyance with the mean varying as a function of the noise exposure. Day-night level (DNL) and day-evening-night level (DENL) were used as noise ...descriptors. Because the entire annoyance distribution has been modeled, any annoyance measure that summarizes this distribution can be calculated from the model. We fitted the model to data from noise annoyance studies for aircraft, road traffic, and railways separately. Polynomial approximations of relationships implied by the model for the combinations of the following exposure and annoyance measures are presented: DNL or DENL, and percentage "highly annoyed" (cutoff at 72 on a scale of 0-100), percentage "annoyed" (cutoff at 50 on a scale of 0-100), or percentage (at least) "a little annoyed" (cutoff at 28 on a scale of 0-100). These approximations are very good, and they are easier to use for practical calculations than the model itself, because the model involves a normal distribution. Our results are based on the same data set that was used earlier to establish relationships between DNL and percentage highly annoyed. In this paper we provide better estimates of the confidence intervals due to the improved model of the relationship between annoyance and noise exposure. Moreover, relationships using descriptors other than DNL and percentage highly annoyed, which are presented here, have not been established earlier on the basis of a large dataset.
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Dostopno za:
BFBNIB, DOBA, IZUM, KILJ, NMLJ, NUK, PILJ, PNG, SAZU, SIK, UILJ, UKNU, UL, UM, UPUK
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