Tag: statistics

J Sleep Res. 2021 Nov 6:e13512. doi: 10.1111/jsr.13512. Online ahead of print.

ABSTRACT

Previous work has shown that both long and short sleep duration is associated with increased mortality, with lowest risk around 7 hr. This has had widespread impact on views on the optimal sleep duration. However, age, being employed/retired, and blue-/white-collar status, may influence the time available for sleep and thus, confound the association. We investigated the role of these factors on the association between sleep duration and mortality. We used employed and retired participants (N = 25,430) from the Swedish National March Cohort and Cox proportional hazards regression to model the shape of the association. We found a significant U-shaped association in a multivariable model with a hazard ratio (HR) of 1.24 (95% confidence interval [CI] 1.10, 1.39) for <5-hr sleep duration, and a HR of 1.30 (95% CI 1.12, 1.51) for ≥9-hr sleep duration, with the lowest HR for 7 hr, but with a span of low HRs from 5 to 8 hr. Unadjusted values showed a pronounced U-shape. Adjusting for age accounted for most of the attenuation in the multivariable model. Stratification into five age groups showed a significant U-shape only in those aged >60.3 years at baseline. The shape of the association did not differ between blue-/white-collar workers, nor between employed and retired groups. We conclude that the U-shaped association between sleep duration and mortality is present only in older individuals.

PMID:34741361 | DOI:10.1111/jsr.13512

Brain Imaging Behav. 2021 Nov 5. doi: 10.1007/s11682-021-00562-0. Online ahead of print.

ABSTRACT

The locus coeruleus is the main noradrenergic nucleus of the brain and is often affected in neurodegenerative diseases. Recently, magnetic resonance imaging with specific T1-weighted sequences for neuromelanin has been used to evaluate locus coeruleus integrity in patients with these conditions. In some of these studies, abnormalities in locus coeruleus signal have also been found in healthy controls and related to ageing. However, this would be at variance with recent post-mortem studies showing that the nucleus is not affected during normal ageing. The present study aimed at evaluating locus coeruleus features in a well-defined cohort of cognitively healthy subjects who remained cognitively intact on a one-year follow-up. An ad-hoc semiautomatic analysis of locus coeruleus magnetic resonance was applied. Sixty-two cognitively intact subjects aged 60-80 years, without significant comorbidities, underwent 3 T magnetic resonance with specific sequences for locus coeruleus. A semi-automatic tool was used to estimate the number of voxels belonging to locus coeruleus and its intensity was obtained for each subject. Each subject underwent extensive neuropsychological testing at baseline and 12 months after magnetic resonance scan. Based on neuropsychological testing 53 subjects were cognitively normal at baseline and follow up. No significant age-related differences in locus coeruleus parameters were found in this cohort. In line with recent post-mortem studies, our in vivo study confirms that locus coeruleus magnetic resonance features are not statistically significantly affected by age between 60 and 80 years, the age range usually evaluated in studies on neurodegenerative diseases. A significant alteration of locus coeruleus features in a cognitively intact elderly subject might be an early sign of pathology.

PMID:34741273 | DOI:10.1007/s11682-021-00562-0

Psychon Bull Rev. 2021 Nov 5. doi: 10.3758/s13423-021-02010-y. Online ahead of print.

ABSTRACT

Research on visual word identification has extensively investigated the role of morphemes, recurrent letter chunks that convey a fairly regular meaning (e.g., lead-er-ship). Masked priming studies highlighted morpheme identification in complex (e.g., sing-er) and pseudo-complex (corn-er) words, as well as in nonwords (e.g., basket-y). The present study investigated whether such sensitivity to morphemes could be rooted in the visual system sensitivity to statistics of letter (co)occurrence. To this aim, we assessed masked priming as induced by nonword primes obtained by combining a stem (e.g., bulb) with (i) naturally frequent, derivational suffixes (e.g., -ment), (ii) non-morphological, equally frequent word-endings (e.g., -idge), and (iii) non-morphological, infrequent word-endings (e.g., -kle). In two additional tasks, we collected interpretability and word-likeness measures for morphologically-structured nonwords, to assess whether priming is modulated by such factors. Results indicate that masked priming is not affected by either the frequency or the morphological status of word-endings, a pattern that was replicated in a second experiment including also lexical primes. Our findings are in line with models of early visual processing based on automatic stem/word extraction, and rule out letter chunk frequency as a main player in the early stages of visual word identification. Nonword interpretability and word-likeness do not affect this pattern.

PMID:34741277 | DOI:10.3758/s13423-021-02010-y

Environ Sci Pollut Res Int. 2021 Nov 5. doi: 10.1007/s11356-021-16937-1. Online ahead of print.

ABSTRACT

The groundwater environment changes under the influence of anthropogenic activities. Because of the construction of the Da’an irrigation area, the amount of irrigation and fertilizer there has changed. Achieving the coordinated development of groundwater resources and economic benefits requires a deeper understanding of the impact of the construction of irrigation areas on groundwater chemistry. In this study, the variations in groundwater chemistry characteristics were studied using statistics and hydrogeochemical methods. Further, the groundwater quality was assessed using the support vector machine method. The results show that the primary water chemistry type was the HCO₃ – Ca – Mg type, with local Fe³⁺ and F^– pollution. After the construction of irrigation area, the SO₄^2-, HCO₃^–, K⁺ + Na⁺, and Ca²⁺ contents decreased, but the Cl^– and Mg²⁺ contents increased. The main nitrogen source in phreatic water was anthropogenic activities, and the main pollution component was NH₄⁺. After the construction of the irrigation area, the NH₄⁺ concentration increased significantly, and the ratio of samples exceeding the standard increased by 37.5%. The over-standard regions spread to the northwest, east, and southeast of Da’an City and east and southeast of the irrigation area. The groundwater quality was predominantly grade IV and V, which accounted for an increase of 16.35%, widely distributed in the south, east, and southwest of the irrigation area and urban areas. The construction of the irrigation area reduced the suitability of phreatic water for agricultural irrigation in the southeast but increased in the west and north.

PMID:34741265 | DOI:10.1007/s11356-021-16937-1

J Neurol. 2021 Nov 5. doi: 10.1007/s00415-021-10881-3. Online ahead of print.

ABSTRACT

Pandemic restrictions have led to changes in therapy plans and disrupted rehabilitation services for people with multiple sclerosis. CogEx is an international, multicentre MS dual-intervention (cognitive rehabilitation, aerobic exercise) randomized, controlled rehabilitation trial confined to people with progressive disease. The primary outcome is cognition (processing speed).There are 11 treatment sites in six countries with participants required to make 27 site visits over 12 weeks. Collectively, the large, in-person demands of the trial, and the varying international policies for the containment of COVID-19, might disproportionately impact the administration of CogEx. During the first lockdown, all centres closed on average for 82.9 (SD = 24.3) days. One site was required to lockdown on two further occasions. One site remained closed for 16 months. Ten staff (19.2%) were required to quarantine and eight staff (15.4%) tested positive for COVID. 10 of 264 (3.8%) participants acquired COVID-19. All survived. The mean duration of enrollment delay has been [236.7 (SD = 214.5) days]. Restarting participants whose interventions were interrupted by the pandemic meant recalculating the intervention prescriptions for these individuals. While the impact of the pandemic on CogEx has been considerable, all study sites are again open. Participants and staff have shown considerable flexibility and resilience in keeping a complex, international endeavour running. The future in general remains uncertain in the midst of a pandemic, but there is cautious optimism the study will be completed with sufficient sample size to robustly evaluate our hypothesis and provide meaningful results to the MS community on the impact of these interventions on people with progressive MS.Trial registration: The trial was registered on September 20th 2018 at www.clinicaltrials.gov having identifier NCT03679468. Registration was performed before recruitment was initiated.

PMID:34741240 | DOI:10.1007/s00415-021-10881-3

Sleep Breath. 2021 Nov 5. doi: 10.1007/s11325-021-02493-y. Online ahead of print.

ABSTRACT

PURPOSE: Although polysomnography (PSG) is the gold standard for monitoring sleep, it has many limitations. We aimed to prospectively determine the validity of wearable sleep-tracking devices and smartphone applications by comparing the data to that of PSGs.

METHODS: Patients who underwent one night of attended PSG at a single institution from January, 2015 to July 2019 were recruited. Either a sleep application or wearable device was used simultaneously while undergoing PSG. Nine smartphone applications and three wearable devices were assessed.

RESULTS: We analyzed the results of 495 cases of smartphone applications and 170 cases of wearables by comparing each against PSG. None of the tested applications were able to show a statistically significant correlation between sleep efficiency, durations of wake time, light sleep or deep sleep with PSG. Snore time correlated well in both of the two applications which provided such information. Deep sleep duration and WASO measured by two of the three wearable devices correlated significantly with PSG. Even after controlling for transition count and moving count, the correlation indices of the wearables did not increase, suggesting that the algorithms used by the wearables were not largely affected by tossing and turning.

CONCLUSIONS: Most of the applications tested in this study showed poor validity, while wearable devices mildly correlated with PSG. An effective use for these devices may be as a tool to identify the change seen in an individual’s sleep patterns on a day-to-day basis, instead of as a method of detecting absolute measurements.

PMID:34741243 | DOI:10.1007/s11325-021-02493-y

Lung. 2021 Nov 6. doi: 10.1007/s00408-021-00490-2. Online ahead of print.

ABSTRACT

Pulmonary hypertension (PH) is associated with decreased survival in patients with pulmonary fibrosis and combined pulmonary fibrosis and emphysema. Main pulmonary artery (PA) diameter and PA diameter/ascending aortic diameter (PA/AA) ratio, as measured on CT, have recently emerged as specific markers for PH. Our single-center retrospective study found that PA/AA ratio > 1 is associated with decreased survival in individuals with pulmonary fibrosis, with or without emphysema. Our study also describes markers of cardiac remodeling, and the echocardiographic diagnosis of PH in this patient population.

PMID:34741227 | DOI:10.1007/s00408-021-00490-2

J Clin Pediatr Dent. 2021 Nov 1;45(5):298-305. doi: 10.17796/1053-4625-45.5.2.

ABSTRACT

OBJECTIVE: The aim of this study is to evaluate the relationship between packaged product label and medication package insert reading habits of parents and their children’s oral/dental health.

STUDY DESIGN: A questionnaire including demographic characteristics and label/insert reading habits was filled by parents of 301 children who referred to the Pediatric Dentistry Department. The children were examined intraorally and dmft/DMFT and ICDAS II scores were recorded. The data were evaluated statistically.

RESULTS: Label and medication package insert reading were found in 71.4% and 88.4% of the parents, respectively. Label reading increased as the age of the child and the number of children in the family increased. Medical package insert reading increased as the mother’s education and SLS/paraben knowledge increased. Decrease of 1 point in ICDAS II resulted in the 1.410 times increase in the rate of medical package insert reading of the parents.

CONCLUSION: It is concluded that improving the label and medical insert reading rate of the parents would be effective for providing better oral and dental health for their children.

PMID:34740268 | DOI:10.17796/1053-4625-45.5.2

J Clin Pediatr Dent. 2021 Nov 1;45(5):306-311. doi: 10.17796/1053-4625-45.5.3.

ABSTRACT

INTRODUCTION: Bioceramic materials, gray and white mineral trioxide aggregate (GMTA, WMTA), have been shown to have high rates of success in various endodontic applications. A major drawback is their tendency to discolor teeth compared to Biodentine (BD), that has been claimed not to discolor teeth. The aim of this study was to compare tooth discoloration after applying different pulpotomy base materials (BD, GMTA and WMTA).

STUDY DESIGN: Forty human incisors teeth were used in this study. Coronal access was achieved by a Tungsten Carbide drill, and the pulp chambers were accessed and chemo-mechanically debrided. Each material was placed in the pulp chamber, up to the cervical sectioning level. All specimens were incubated at 37°C and 100% humidity for three months and have been evaluated before the study and weekly. Color was assessed according to the CIE L*a*b* color space system.

RESULTS: ΔE of all experimental groups (GMTA, WMTA and BD) were significantly different from the control group at all time points (P<0.05). Color changes in the GMTA and WMTA groups, had no statistically significant differences, but showed higher discoloration compared to BD group in the cervical part of the crown, since week 1 (P<0.05). WMTA group showed significant discoloration in the cervical part as of week 1 (P<0.05), and gradually increased over time (Figure 2). BD group showed no significantly discoloration over time. GMTA group showed the significant discoloration at week 1 and week 14 (P<0.05).

CONCLUSIONS: both GMTA and WMTA pulpotomy materials may discolor tooth structure over time in an extracted permanent anterior tooth model. When choosing bioceramic pulpotomy material, BD may be preferable in esthetic area.

PMID:34740264 | DOI:10.17796/1053-4625-45.5.3

J Clin Pediatr Dent. 2021 Nov 1;45(5):317-322. doi: 10.17796/1053-4625-45.5.5.

ABSTRACT

PURPOSE: To evaluate the effects of different treatment time of 5.25% Sodium hypochlorite (NaOCl) on the microshear bond strength (μSBS), attenuated total reflection Fourier transform infrared (ATR-FTIR) and etching pattern in mild and moderate fluorotic enamel.

STUDY DESIGN: Forty-eight fluorotic molars were divided into two groups: mild and moderate fluorotic enamel which were classified by a Thylstrup and Fejerskov index (TFI). Based on the application time (0s, 60s, 120s, 180s) of 5.25% NaOCl, each group was sectioned into four parts. Then the etched enamel was bonded with resin and tested to acquire μSBS. The statistical method was two-way ANOVA and Least Significant Difference (LSD) test at α = 0.05. Besides, fracture modes were observed under a stereo microscope. SEM was used to evaluated the enamel-etching pattern and organic content on the fluorotic enamel surface were investigated by ATR-FTIR.

RESULTS: Duration of 5.25% NaOCl at 60s or 120s significantly increased the μSBS of fluorotic enamel compared to 0s (p<0.05). Fracture modes indicated that dominating failures were set in the bonding interface but whose proportion decreased when 5.25% NaOCl was applied. The enamel-etching pattern in 180s was deepest under SEM. Spectra of enamel samples manifested an obvious and gradual removal of its organic phase after duration of NaOCl increased.

CONCLUSION: The maximal μSBS is acquired by using 5.25% NaOCl at 60s for mild fluorotic enamel but 120s for the moderate. The prolonged application time of 5.25% NaOCl prior to phosphoric acid etching improves enamel-etching pattern. Treatment of 5.25% NaOCl decreases proteins on the fluorotic enamel surface.

PMID:34740266 | DOI:10.17796/1053-4625-45.5.5