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Sleep disturbances, a debilitating symptom of Alzheimer's disease (AD), are associated with neuropathological changes. However, the relationship between these disturbances and regional neuron and astrocyte pathologies remains unclear. This study examined whether sleep disturbances in AD result from pathological changes in sleep-promoting brain areas. Male 5XFAD mice underwent electroencephalography (EEG) recordings at 3, 6, and 10 months, followed by an immunohistochemical analysis of three brain regions associated with sleep promotion. The findings showed that 5XFAD mice demonstrated reduced duration and bout counts of nonrapid eye movement (NREM) sleep by 6 months and reduced duration and bout counts of rapid eye movement (REM) sleep by 10 months. Additionally, peak theta EEG power frequency during REM sleep decreased by 10 months. Sleep disturbances correlated with the total number of GFAP-positive astrocytes and the ratio of GFAP- and GABA-positive astrocytes across all three sleep-associated regions corresponding to their roles in sleep promotion. The presence of GABRD in sleep-promoting neurons indicated their susceptibility to inhibition by extrasynaptic GABA. This study reveals that neurotoxic reactive astrogliosis in NREM and REM sleep-promoting areas is linked to sleep disturbances in 5XFAD mice, which suggests a potential target for the treatment of sleep disorders in AD.

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Technology permeates all walks of life. It has emerged as a global facilitator to improve learning and training, alleviating the temporal and spatial limitations of traditional learning systems. It is imperative to identify enablers or inhibitors of technology adoption by employees for sustainable change in education management systems. Using the theoretical lens of organizational support theory, this paper studies effect of institutional support on education management information systems (EMIS) use along with two individual traits of self-efficacy and innovative behavior of academic employees in British higher educational institutions. Data for this cross-sectional study were collected through a questionnaire completed by 591 academic employees of 23 universities from 10 cities in the United Kingdom. Partial Least Square structural equation modeling was used to analyze data with smartPLS 3.2.9 software. Results indicate that institutional support promotes self-efficacy and innovative behavior that help develop positive employee perceptions. The model explains a 52.9% variance in intention to use. Post-hoc mediation analysis shows that innovativeness and self-efficacy mediate between institutional support and employee technology adoption behavior. As opposed to student samples in past studies on educational technology, this study adds to the literature by focusing on academic employees.

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Box surgery for obstructive sleep apnea (OSA) patients consists of mandibular surgery, including genioglossus advancement, hyoid suspension, and maxillomandibular advancement, as an airway reconstruction. This surgery was developed in the early 1980s. Thereafter, techniques were modified in each surgery for the enhancement of outcome and prevention of complications. However, the indication for surgery remains poorly defined due to the dynamicity of the upper airway, variability of the phenotype in OSA patients, and absence of a representative method for the obstruction site in the upper airway. As a result, box surgery is performed restrictively. On the development of an evaluation method including radiologic and endoscopic examination during sleep, the indications and surgical outcomes of each box surgery should be standardized and reevaluated. In this review, the development and limitations of box surgery will be discussed for the positive future of this surgery.

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We investigated the interspecific variability in nocturnal whole-plant stomatal conductance under well-watered and drought conditions in seedlings of four species of Populus from habitats characterized by abundant water supply (mesic and riparian) or from drier upland sites. The study was carried out to determine whether (i) nocturnal conductance varies across different species of Populus according to their natural habitat, (ii) nocturnal conductance is affected by water stress similarly to daytime conductance based on species habitat and (iii) differences in conductance among species could be explained partly by differences in stomatal traits. We measured whole-plant transpiration and conductance (G) of greenhouse-grown seedlings using an automated high-resolution gravimetric technique. No relationship was found between habitat preference and daytime G (GD), but night-time G (GN) was on average 1.5 times higher in riparian and mesic species (P. deltoides Bartr. ex Marsh. and P. trichocarpa Torr. & Gray) than in those from drier environments (P. tremuloides Michx. and P. × petrowskyana Schr.). GN was not significantly reduced under drought in riparian species. Upland species restricted GN significantly in response to drought, but it was still at least one order of magnitude greater that the cuticular conductance until leaf death was imminent. Under both well-watered and drought conditions, GN declined with increasing vapour pressure deficit (D). Also, a small increase in GN towards the end of the night period was observed in P. deltoides and P. × petrowskyana, suggesting the involvement of endogenous regulation. The anatomical analyses indicated a positive correlation between G and variable stomatal pore index among species and revealed that stomata are not likely to be leaky but instead seem capable of complete occlusion, which raises the question of the possible physiological role of the significant GN observed under drought. Further comparisons among closely related species that occupy ecologically diverse habitats may provide a better understanding of the genetic versus environmental regulations of nocturnal water loss.

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This study compared the sprint performance of professional cyclists after 10 minutes of variable (VAR) or nonvariable (N-VAR) high-intensity cycling with sprint performance in a rested state. Ten internationally competitive male cyclists (mean ± SD: age, 20.1 ± 1.3 years; stature, 1.81 ± 0.07 m; body weight, 69.5 ± 4.9 kg; and V[Combining Dot Above]O2peak, 72.5 ± 4.4 ml·kg·min) performed a 12-second maximal sprint in 3 conditions: (a) a rested state, (b) after 10 minutes of N-VAR cycling, and (c) after 10 minutes of VAR cycling. The intensity during the 10-minute efforts gradually increased to replicate power output observed in the final section of cycling road races. During the VAR cycling, participants performed short (2 seconds) accelerations at 80% of their sprint peak power, every 30 seconds. Average power output, cadence, and maximal heart rate (HR) during the 10-minute efforts were similar between conditions (5.3 ± 0.2 W·kg, 102 ± 1 rpm, and 93 ± 3% HRmax). Postexercise blood lactate concentration and sessional perceived exertion were also similar (8.3 ± 1.6 mmol·L, 15.4 ± 1.3 [6-20 scale]). Peak and average power output and cadence during the subsequent maximal sprint were not different between the 3 experimental conditions (p > 0.05). In conclusion, this study showed that neither the VAR nor the N-VAR 10-minute efforts ridden in this study impaired sprint performance in elite competitive cyclists.

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Symptomatic laryngeal chondrometaplasia is rare. To the best of our knowledge, there are only few case reports on laryngeal chondrometaplasia. The imaging appearance of this uncommon disease is even more rarely described. There are only two case reports describing its appearances in computed tomography (CT) and magnetic resonance imaging (MRI). Ultrasound (US) features have not been reported so far. This case report is to show the US, CT and MRI features of this disease entity to stress the role of imaging in this disease.

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Autopsy is very important in medical practice and is being increasingly relegated both in the developed and developing countries. Though autopsy rate has been on the decline; the exact rates are difficult to determine because various reports are influenced by many factors. The danger of the decline in the developing countries is that equipment for proper diagnosis is not yet available; therefore; most diagnoses are not made and the cause of death would not have been known. This article reviews the benefits of autopsy in modern practice; the importance of perinatal autopsy and the shortcomings of modern technology in the diagnosis and determination of the cause of death. Electronic literature search combined with the review of both local publications and relevant texts were carried out. Clinicians should endeavor to request for postmortem examination as the benefits far outweigh the reasons proffered for the decline in the autopsy rate

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BACKGROUND: The present study validates and evaluates the sensitivity and specificity of four internationally popular questionnaires, translated into Chinese, for assessing suspected obstructive sleep apnea (OSA) patients, namely, the Berlin questionnaire, the ASA checklist, the STOP questionnaire and the STOP-BANG questionnaire. Their predictive values in OSA risks in patients presenting with OSA symptoms are examined. Questionnaires may be helpful in prioritizing polysomnography (PSG) and in treatment for the more severe cases. METHODS: All patients attending our sleep laboratory for overnight PSG were recruited. They were asked to complete three questionnaires (Berlin, ASA checklist and STOP) 2 weeks before and on the same night as the PSG. STOP-BANG questionnaire, an extended STOP with demographic data, 'B'-body mass index (BMI), 'A'-age, 'N'-neck circumference and 'G'-gender was completed by our technologists using the patient's completed STOP. RESULTS: A number of 141 patients were recruited. The sensitivities and specificities for STOP-BANG with cutoffs at PSG's RDI=5, RDI=15 and RDI=30 were 81% to 86% and 34% to 57%, respectively. The high-risk group patients identified by STOP-BANG had significantly higher respiratory disturbance index and lower minimum oxygen saturation than the low-risk group patients. CONCLUSION: Among the four questionnaires studied, STOP-BANG, with only eight questions and the highest sensitivity, is the best questionnaire of the four for OSA screening. This can potentially assist in prioritizing PSG and can be helpful in clinical or self-evaluation by the general public.

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OBJECTIVE: This study examines subjects' level of consciousness with bispectral analysis in sedation endoscopy of the upper airway. STUDY DESIGN: A prospective study. SETTING: University hospital. SUBJECTS AND METHODS: Bispectral analysis levels recorded in natural sleep of 43 patients with obstructive sleep apnea during an overnight polysomnographic sleep study were directly compared with the levels recorded during midazolam sedation sleep endoscopy in the same subjects. The possible muscle relaxation effect of midazolam was examined via surface chin electrodes. Supine Müller maneuver findings in 50 patients with obstructive sleep apnea were also compared with soft tissue dynamics during midazolam sedation sleep endoscopy. RESULTS: In our study of the 43 patients with bispectral analysis during natural sleep and midazolam sedation sleep endoscopy, a predominance of bispectral analysis values indicating N1 and N2 sleep was observed during the sedation study. Midazolam failed to achieve deeper levels of sleep with minimal N3 and no convincing rapid eye movement. As N1 and N2 are the stages during which maximal dynamic activities occur, and they make up an average of 70.5% of total sleep time, from 210 sleep studies at our laboratory, the present technique would be ideal as a surgical assessment tool. No muscle relaxation effect could be detected at our protocol dose of midazolam. The supine Müller maneuver findings were significantly different from those observed during sedation sleep. CONCLUSION: These findings support the value of sleep endoscopy as an efficient and informative technique for the examination of upper airway dynamics relevant to focused surgical planning.

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BACKGROUND: Cervical cancer is the second commonest cancrin the world. OBJECTIVE: The study is to evaluate the prevalence and histopathological pattern of cervical cancer in the University of Benin Teaching Hospital, Benin City. METHODS: All the tissue slides of specimen [cervix and hysterectomy] diagnosed as cervical carcinoma over a period of 20 years [1987-2006] were retrieved and reevaluated for confirmation of diagnosis and tumour typing in the Department of Pathology, University of Benin Teaching Hospital, Benin City. Clinical data were obtained from histopathology registers, request forms as well as case notes of patients obtained from the Records Department. RESULTS: A total of 598 cases of cancer of the cervix constituting 63.7% of gynaecological cancers were seen during the 20 year study period. The age range for cervical cancer was 15-90 years with a mean age of 50.4 years (SD +/- 13.5) and a peak occurrence in the 5th decade. Squamous cell carcinoma (92.3%) was the most common histological type of cervical cancer, followed by adenocarcinoma (6.0%) and adenosquamous carcinoma (1.0%). Glassy cell carcinoma, undifferentiated carcinoma malignant mixed mullerian tumour and rhabdomyosarcoma were rare constituting 1 (0.2) case each. CONCLUSION: This study has shown a high incidence of carcinoma of cervix at the University of Benin Teaching Hospital. It is necessary to establish effective screening centres and educate the populace in order to raise the level of awareness and increase the early detection of preinvasive lesions.

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As more researchers utilize the Five-factor model (FFM) of personality with children and adolescents, the need for instruments designed specifically for use with children and adolescents increases. In the United States, the 108-item Inventory of Children's Individual Differences (ICID; Halverson et al., 2003), has provided researchers with an age and culture neutral instrument designed specifically to assess the FFM of personality in children and adolescents, ages 2 to 15, using parental, nonparental, or self-reports. This article presents a shorter, 50-item version of the ICID (the ICID-S) that maintains the levels of validity and reliability previously established for the full instrument.

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OBJECTIVE: To establish an olfactory test in the Hong Kong Chinese population. STUDY DESIGN: Prospective analysis of the results of a combined olfactory test (COT) for patients with olfactory dysfunction and for normal subjects attending a secondary and tertiary ear, nose and throat centre. METHOD: Our COT was based on and modified from the Connecticut Chemosensory Research Centre test. It consisted of an odour identification test involving nine substances and a threshold test using a series of threefold dilutions of 1-butanol. From September 1998 to June 2002, 188 Hong Kong Chinese patients with olfactory dysfunction and subjects with normal olfaction were prospectively recruited. The subjects were categorized into normal, hyposmic and anosmic groups. The olfactory function of the main group of subjects (n = 153) was assessed with the COT by a blinded observer and also quantified with a visual analogue scale; the results were analysed to validate the discriminative ability of the COT. Another subgroup of subjects (n = 35) was tested with the COT twice with a two-week interval to evaluate test-retest reliability. RESULTS: There were 42 normal, 68 hyposmic and 43 anosmic subjects within the main group (total n = 153). The identification scores, threshold scores and combined olfactory scores were statistically significantly different between the anosmic, hyposmic and normal groups of subjects (p < 0.001). The combined olfactory score correlated with the visual analogue score and the correlation coefficient was 0.56 (p < 0.01). The mean time spent on each COT was 8.6 minutes (standard deviation = 3.4 minutes). The test-retest reliability of the COT was satisfactory, with a one-way model intraclass correlation coefficient of 0.87 (n = 35). CONCLUSION: The satisfactory discriminative ability and test-retest reliability of the COT have been demonstrated in this study. The COT is a feasible method for assessing sense of smell in the Hong Kong Chinese population.

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Little information exists on the power output demands of competitive women's road cycle racing. The purpose of our investigation was to document the power output generated by elite female road cyclists who achieved success in FLAT and HILLY World Cup races. Power output data were collected from 27 top-20 World Cup finishes (19 FLAT and 8 HILLY) achieved by 15 nationally ranked cyclists (mean +/- SD; age: 24.1+/-4.0 years; body mass: 57.9+/-3.6 kg; height: 168.7+/-5.6 cm; VO2max 63.6+/-2.4 mL kg(-1) min(-1); peak power during graded exercise test (GXT(peak power)): 310+/-25 W). The GXT determined GXT(peak power), VO2peak lactate threshold (LT) and anaerobic threshold (AT). Bicycles were fitted with SRM powermeters, which recorded power (W), cadence (rpm), distance (km) and speed (km h(-1)). Racing data were analysed to establish time in power output and metabolic threshold bands and maximal mean power (MMP) over different durations. When compared to HILLY, FLAT were raced at a similar cadence (75+/-8 vs. 75+/-4 rpm, P=0.93) but higher speed (37.6+/-2.6 vs. 33.9+/-2.7 km h(-1), P=0.008) and power output (192+/-21 vs. 169+/-17 W, P=0.04; 3.3+/-0.3 vs. 3.0+/-0.4 W kg(-1), P=0.04). During FLAT races, riders spent significantly more time above 500 W, while greater race time was spent between 100 and 300 W (LT-AT) for HILLY races, with higher MMPs for 180-300 s. Racing terrain influenced the power output profiles of our internationally competitive female road cyclists. These data are the first to define the unique power output requirements associated with placing well in both flat and hilly women's World Cup cycling events.

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The purpose of this study was to investigate convergent and discriminant validity of the five-factor model of adolescent personality in a school setting using three different raters (methods): self-ratings, peer ratings, and teacher ratings. The authors investigated validity through a multitrait-multimethod matrix and a confirmatory factor analysis correlated trait, uncorrelated method model. With the exception of Emotional Stability, each analysis demonstrated similar patterns and together provided support for the convergent and discriminant validity of the five-factor model structure of adolescent personality. However, among the three raters, self-ratings of personality provided a comparatively weaker method for assessing adolescent personality. The influences of agreement between self and other raters are discussed in relation to contrast, perceiver, and target effects; expert observer effects; the degree of acquaintanceship; and the effect of the social context.

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Based on over 50,000 parental descriptors of children gathered in eight different countries, we used a combination of focus group sorting of descriptors in each country and factor analyses of instruments developed in four of the countries (United States, China, Greece, and the Netherlands) to describe children ages 3 to 12 years to select items for an instrument that would work well across countries to access personality. Through many factor analyses of indigenous items in each country, a core set of 141 items was used in three of the countries, with over 3000 parents responding to our instruments in China, Greece, and the United States. Much cross-comparative research analysis has resulted in 15 robust midlevel scales that describe the structures of parental descriptors that are common to the three countries. The data on the English (U.S.) sample are presented in detail. Links to temperament and behavior problems are presented and discussed.

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