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BACKGROUND: Meningiomas are the most common primary benign brain tumors in adults. Given the extended life expectancy of most meningiomas, consideration of quality of life (QOL) is important when selecting the optimal management strategy. There is currently a dearth of meningioma-specific QOL tools in the literature. OBJECTIVE: In this systematic review, we analyze the prevailing themes and propose toward building a meningioma-specific QOL assessment tool. METHODS: A systematic search was conducted, and only original studies based on adult patients were considered. QOL tools used in the various studies were analyzed for identification of prevailing themes in the qualitative analysis. The quality of the studies was also assessed. RESULTS: Sixteen articles met all inclusion criteria. Fifteen different QOL assessment tools assessed social and physical functioning, psychological, and emotional well-being. Patient perceptions and support networks had a major impact on QOL scores. Surgery negatively affected social functioning in younger patients, while radiation therapy had a variable impact. Any intervention appeared to have a greater negative impact on physical functioning compared to observation. CONCLUSION: Younger patients with meningiomas appear to be more vulnerable within social and physical functioning domains. All of these findings must be interpreted with great caution due to great clinical heterogeneity, limited generalizability, and risk of bias. For meningioma patients, the ideal QOL questionnaire would present outcomes that can be easily measured, presented, and compared across studies. Existing scales can be the foundation upon which a comprehensive, standard, and simple meningioma-specific survey can be prospectively developed and validated.
The purpose of this study was to investigate whether significant difference exists on radiation dose delivered to organs at risks in megavoltage computed tomography (MVCT) verification using three predefined scanning modes, namely fine (2 mm), normal (4 mm) and coarse (6 mm). This will provide information for the imaging protocol of tomotherapy for the left breast.
Materials and methods
Organ doses were measured using thermoluminescent dosimeters (TLD-100) placed within a female Rando phantom for MVCT imaging. Kruskal–Wallis test was conducted with p<0·05 to evaluate the significant difference between the three MVCT scanning modes.
Statistically significant difference existed in organ absorbed dose between different scan mode selections (p<0·001). Relative to the normal scan selection (4 mm), the absorbed dose to the organs of interests can be scaled down by 0·7 and scaled up by 2·1 for coarse (6 mm) and fine scans (2 mm) respectively.
Optimisation of imaging protocols is of paramount importance to keep the radiation exposure ‘as low as reasonably achievable’. The recommendation of undergoing daily coarse mode for MVCT verification in breast tomotherapy not only mitigates the radiation exposure to normal tissues, but also trims the scan-acquisition time.
Evidence suggests that autism and schizophrenia share similarities in genetic, neuropsychological and behavioural aspects. Although both disorders are associated with theory of mind (ToM) impairments, a few studies have directly compared ToM between autism patients and schizophrenia patients. This study aimed to investigate to what extent high-functioning autism patients and schizophrenia patients share and differ in ToM performance.
Thirty high-functioning autism patients, 30 schizophrenia patients and 30 healthy individuals were recruited. Participants were matched in age, gender and estimated intelligence quotient. The verbal-based Faux Pas Task and the visual-based Yoni Task were utilised to examine first- and higher-order, affective and cognitive ToM. The task/item difficulty of two paradigms was examined using mixed model analyses of variance (ANOVAs). Multiple ANOVAs and mixed model ANOVAs were used to examine group differences in ToM.
The Faux Pas Task was more difficult than the Yoni Task. High-functioning autism patients showed more severely impaired verbal-based ToM in the Faux Pas Task, but shared similar visual-based ToM impairments in the Yoni Task with schizophrenia patients.
The findings that individuals with high-functioning autism shared similar but more severe impairments in verbal ToM than individuals with schizophrenia support the autism–schizophrenia continuum. The finding that verbal-based but not visual-based ToM was more impaired in high-functioning autism patients than schizophrenia patients could be attributable to the varied task/item difficulty between the two paradigms.
During 1990 we surveyed the southern sky using a multi-beam receiver at frequencies of 4850 and 843 MHz. The half-power beamwidths were 4 and 25 arcmin respectively. The finished surveys cover the declination range between +10 and −90 degrees declination, essentially complete in right ascension, an area of 7.30 steradians. Preliminary analysis of the 4850 MHz data indicates that we will achieve a five sigma flux density limit of about 30 mJy. We estimate that we will find between 80 000 and 90 000 new sources above this limit. This is a revised version of the paper presented at the Regional Meeting by the first four authors; the surveys now have been completed.
Parotid gland tumours are complex neoplasms with a broad histological range. The parotid gland is also a common site of face and scalp skin cancer metastases.
Parotidectomies performed by ENT department in the Gold Coast health district from 2006 to 2013.
A total of 158 specimens were examined. Of these, 53.80 per cent were benign and 46.20 per cent were malignant. Pleomorphic adenoma was the most common tumour (29.11 per cent), followed by cutaneous squamous cell carcinoma (23.42 per cent) and Warthin's tumour (12.03 per cent).
Metastatic squamous cell carcinoma accounted for a large proportion of parotid masses in our case series, reflecting the high prevalence of non-melanoma skin cancer in Australia. Primary parotid neoplasms had similar incidence rates to other studies.
In traditional transit timing variations (TTVs) analysis of multi-planetary systems, the individual TTVs are first derived from transit fitting and later modelled using n-body dynamic simulations to constrain planetary masses. We show that fitting simultaneously the transit light curves with the system dynamics (photo-dynamical model) increases the precision of the TTV measurements and helps constrain the system architecture. We exemplify the advantages of applying this photo-dynamical model to a multi-planetary system found in K2 data very close to 3:2 mean motion resonance, K2-19. In this case the period of the larger TTV variations (libration period) is much longer (>1.5 years) than the duration of the K2 observations (80 days). However, our method allows to detect the short period TTVs produced by the orbital conjunctions between the planets that in turn permits to uniquely characterise the system. Therefore, our method can be used to constrain the masses of near-resonant systems even when the full libration curve is not observed.
Some studies demonstrated that physical activity may have beneficial effect on cognitive function. The objective of the study was to estimate the association between physical activity and cognitive function in community-dwelling elderly Chinese in Hong Kong (HK) and Guangzhou (GZ).
In the neighborhood of HK and GZ, a convenience sample of 557 (260 in HK and 297 in GZ) older persons without dementia aged over 60 years (73.4 ± 6.5) was recruited. Physical activity was measured using a checklist. Information on physical activity participation, cognitive function, and other variables were collected. Multivariate linear regression analyses were performed to evaluate the association between physical activity and cognitive function.
Total number of physical activities showed significant association with the delayed recall test (p < 0.01) and category verbal fluency test (CVFT) (p < 0.01). However, with further adjustment for participation in intellectual activity, the coefficients were no longer statistically significant (p > 0.05)
Physical activity may not be associated with better cognitive function among elderly Chinese independently of other factors.
With the proportion of older adults in Hong Kong projected to double in size in the next 30 years, it is important to develop measures for detecting individuals in the earliest stage of Alzheimer's disease (AD, 0.5 in Clinical Dementia Rating, CDR). We tested the utility of a non-verbal prospective memory task (PM, ability to remember what one has to do when a specific event occurs in the future) as an early marker for AD in Hong Kong Chinese.
A large community dwelling sample of older adults who are healthy controls (CDR 0, N = 125), in the earliest stage of AD (CDR 0.5, N = 125), or with mild AD (CDR 1, N = 30) participated in this study. Their reaction time/accuracy data were analyzed by mixed-factor analyses of variance to compare the performance of the three CDR groups. Logistic regression analyses were performed to test the discriminative power of these measures for CDR 0 versus 0.5 participants.
Prospective memory performance declined as a function of AD severity: CDR 0 > CDR 0.5 > CDR 1, suggesting the effects of early-stage AD and AD progression on PM. After partialling out the variance explained by psychometric measures (e.g., ADAS-Cog), reaction time/accuracy measures that reflected the PM still significantly discriminated between CDR 0 versus 0.5 participants in most of the cases.
The effectiveness of PM measures in discriminating individuals in the earliest stage of AD from healthy older adults suggests that these measures should be further developed as tools for early-stage AD discrimination.
Sharper nanotips are required for application in nanoprobing systems due to a shrinking contact size with each new transistor technology node. We describe a two-step etching process to fabricate W nanotips with controllable tip dimensions. The first process is an optimized AC electrochemical etching in KOH to fabricate nanotips with a radius of curvature (ROC) down to 90 nm. This was followed by a secondary nanotip sharpening process by laser irradiation in KOH. High aspect ratio nanotips with ROC close to 20 nm were obtained. Finally we demonstrate the application of the fabricated nanotips for nanoprobing on advanced technology SRAM devices.
Previous studies have suggested that Lingzhi (Ganoderma lucidum) has antioxidant effects and possibly beneficial effects on blood pressure, plasma lipids and glucose, but these have not been confirmed in subjects with mild hypertension or hyperlipidaemia. The objective of the present study was to assess the cardiovascular, metabolic, antioxidant and immunomodulatory responses to therapy with Lingzhi in patients with borderline elevations of blood pressure and/or cholesterol in a controlled cross-over trial. A total of twenty-six patients received 1·44 g Lingzhi daily or matching placebo for 12 weeks in a randomised, double-blind, cross-over study with placebo-controlled run-in and cross-over periods. Body weight, blood pressure, metabolic parameters, urine catecholamines and cortisol, antioxidant status and lymphocyte subsets were measured after each period. Lingzhi was well tolerated and data from twenty-three evaluable subjects showed no changes in BMI or blood pressure when treated with Lingzhi or placebo. Plasma insulin and homeostasis model assessment-insulin resistance were lower after treatment with Lingzhi than after placebo. TAG decreased and HDL-cholesterol increased with Lingzhi but not with placebo in the first treatment period, but significant carry-over effects prevented complete analysis of these parameters. Urine catecholamines and cortisol, plasma antioxidant status and blood lymphocyte subsets showed no significant differences across treatments. Results indicate that Lingzhi might have mild antidiabetic effects and potentially improve the dyslipidaemia of diabetes, as shown previously in some animal studies. Further studies are desirable in patients with hyperglycaemia.
TiO2 thin films were grown epitaxially on (1120) sapphire (α-Al2O3) at 800 °C by the MOCVD method. The TiO2 films and TiO2/Al2O3 interfaces were characterized by TEM and HREM. The observations indicate that the TiO2 films are single crystalline and have the rutile structure. A majority of the films has the epitaxial orientation relationship between the TiO2 rutile films (R) and the α-Al2O3 substrates (S): (101)R||(1120)S, while the epitaxial relationship of (100)R||(1120)s has also been observed for one film. HREM studies show that the (100) film was grown on an off-cut substrate, vicinal to (1120). Detailed atomic structures of the interfaces will be presented and discussed in terms of the growth mechanism and misfit dislocation structure.
We studied the finite size effect on the metal-insulator phase transition and the accompanying tetragonal to monoclinic structural phase transition of VO2 films grown by MOCVD. X-ray diffraction measurements and electrical conductivity measurements were done as a function of temperature for VO2 films with out-of plane particle size ranging from 60–310Å. Each VO2 film was grown on a thin TiO2 buffer layer, which in turn was grown by MOCVD on a polished sapphire (1120) substrate. The transition was found to be first order. As the out-of plane particle size becomes larger, the transition temperature shifts and the transition width narrows. For the 60Å film the transition was observed at ∼61°C with a transition width of ∼10°C, while for the 310Å film the transition temperature was ∼59°C and the transition width ∼2°C. We also observed thermal hysteresis for each film, which became smaller with increasing particle size.
Recent experimental developments have cast doubt on the validity of the common assumption that the distribution of tail states of hydrogenated amorphous silicon exhibits a single exponential functional form. We employ transient photocurrent decay measurements to determine this distribution of tail states. In our approach, however, we determine the distribution of tail states directly from the experimental data, without assuming, a priori, a specific functional form. It is found that these experimental results are consistent with other more recent experimental determinations of the distribution of tail states, suggesting the possibility of deviations from a single exponential distribution of tail states in hydrogenated amorphous silicon.
Background: Alzheimer's disease (AD) is a neurodegenerative disease with a higher prevalence in women. Expression of estrogen receptor 1 (ESR1) gene has been identified throughout the brain. Owing to the putative neuroprotective effects of estrogen, estrogen receptor gene is a potential candidate modulating the development of AD. Preliminary associations between two polymorphisms of ESR1 (PvuII and XbaI) gene and AD have been reported.
Methods: In this study, 16 single nucleotide polymorphisms (SNPs) of the ESR1 gene (including four commonly studied ESR1 SNPs and 12 other tagging SNPs selected from the HapMap database) were investigated to further evaluate the association between ESR1 polymorphisms and the risk of AD in the Chinese population.
Results: A total of 233 Chinese AD patients and 245 age-matched elderly control subjects were recruited. Genetic associations were analyzed by chi-square test and interaction effect was analysed by logistic regression analysis. Five SNPs (clustered between intron 3 and intron 7) were associated with the risk of AD (p-value ranges from 0.001 to 0.035); another two SNPs (located on exon 2 and intron 2) were shown to modulate the age-at-onset (AAO) in AD (p-value = 0.036 and 0.011).
Conclusions: ESR1 gene polymorphisms may be associated with the AAO in AD. The present results provided information for possible associations between certain polymorphisms of ESR1 gene and the risk of AD.
Background: Growing evidence suggests that participation in late-life leisure activity may have beneficial effects on cognitive function. The objective of the study was to evaluate the association between leisure activity participation and cognitive function in an elderly population of community-dwelling Hong Kong Chinese.
Methods: 512 participants were assessed in the follow-up study of a population-based community survey of the prevalence of cognitive impairment among Hong Kong Chinese aged 60 years and over. Leisure activities were classified into four categories (physical, intellectual, social and recreational). Information regarding leisure activity participation, cognitive function and other variables was collected. Multivariate linear regression analyses were performed to examine the association between leisure activity participation and cognitive function.
Results: A higher level of late-life leisure activity participation, particularly in intellectual activities, was significantly associated with better cognitive function in the elderly, as reflected by the results of the Cantonese Mini-mental State Examination (p = 0.007, 0.029 and 0.005), the Category Verbal Fluency Test (p = 0.027, 0.003 and 0.005) and digit backward span (p = 0.031, 0.002 and 0.009), as measured by the total frequency, total hours per week and total number of subtypes, respectively; the Chinese Alzheimer's Disease Assessment Scale-Cognitive Subscale (p = 0.045) and word list learning (p = 0.003), as measured by the total number of subtypes; and digit forward span (p = 0.007 and 0.015), as measured by the total hours per week and total number of subtypes, respectively.
Conclusion: Late-life intellectual activity participation was associated with better cognitive function among community-dwelling Hong Kong elderly Chinese.
The emergence of the novel swine-origin influenza A (H1N1) virus in humans has aroused great concern among medical professionals about the possible evolution of a full-blown influenza pandemic, one on the scale of the “Spanish” influenza pandemic of 1918–19 (Belshe, 2009). It has been speculated that the return of a pandemic virus equivalent in pathogenicity to the virus of 1918 would likely kill more than 100 million people worldwide, including a large number of economically active young people (Taubenberger and Morens, 2006). Health administrations worldwide have stepped up reporting and surveillance of the deaths and illnesses associated with H1N1, and most countries have national strategies to fight the outbreak, though skeptics doubt how such plans could be operationalized, especially in developing countries (Coker, 2009). As of 6 July 2009, the cumulative total of H1N1 cases exceeds 90,000 in over 100 countries, with over 400 deaths directly related to the infection (World Health Organization, 2009a). Optimists might believe this pandemic is not going to match the scale of the historical 1918 pandemic given the relatively low fatality rate observed thus far. However, the World Health Organization has cautioned that we have just entered Phase 6 of the pandemic – i.e. we are in the early days of the 2009 flu pandemic (Chan, 2009). The course of the pandemic is thus unpredictable at this stage but it is evident that international multilateral plans and agreements have enabled much greater coordination of communication and action than ever before. The guidance behind these multilateral international actions, rooted in the World Health Organization's International Health Regulations (IHR) 2005, only came into being five years ago in response to the threat of emerging infectious diseases and particularly by the events related to the emergence of Severe Acute Respiratory Syndrome (SARS) (Katz, 2009). The morbidity and mortality directly resulting from this novel influenza A H1N1 outbreak are in the center of the world media's spotlight, but the potential impact of the pandemic on global mental health has not yet received the attention it deserves.
Three-dimensional numerical simulations of laminar flow around a circular cylinder with sinusoidal variation of cross-section along the spanwise direction, named ‘wavy cylinder’, are performed. A series of wavy cylinders with different combinations of dimensionless wavelength (λ/Dm) and wave amplitude (a/Dm) are studied in detail at a Reynolds number of Re = U∞Dm/ν = 100, where U∞ is the free-stream velocity and Dm is the mean diameter of a wavy cylinder. The results of variation of mean drag coefficient and root mean square (r.m.s.) lift coefficient with dimensionless wavelength show that significant reduction of mean and fluctuating force coefficients occurs at optimal dimensionless wavelengths λ/Dm of around 2.5 and 6 respectively for the different amplitudes studied. Based on the variation of flow structures and force characteristics, the dimensionless wavelength from λ/Dm = 1 to λ/Dm = 10 is classified into three wavelength regimes corresponding to three types of wake structures. The wake structures at the near wake of different wavy cylinders are captured. For all wavy cylinders, the flow separation line varies along the spanwise direction. This leads to the development of a three-dimensional free shear layer with periodic repetition along the spanwise direction. The three-dimensional free shear layer of the wavy cylinder is larger and more stable than that of the circular cylinder, and in some cases the free shear layer even does not roll up into a mature vortex street behind the cylinder. As a result, the mean drag coefficients of some of the typical wavy cylinders are less than that of a corresponding circular cylinder with a maximum drag coefficient reduction up to 18%. The r.m.s. lift coefficients are greatly reduced to practically zero at optimal wavelengths. In the laminar flow regime (60 ≤ Re ≤ 150), the values of optimal wavelength are Reynolds number dependent.
Background: Increasing evidence suggests that functional impairment can be detected in older persons with mild cognitive impairment (MCI). This study explores the functional profiles and the clinical correlates of a population-based sample of Chinese older persons with MCI in Hong Kong.
Methods: A random sample of 765 Chinese elderly subjects without dementia was recruited, of which 389 were elderly normal controls (Clinical Dementia Rating = 0), and 376 had questionable dementia (CDR = 0.5). The latter were categorized into an MCI group (n = 291) and a very mild dementia (VMD) group (n = 85). Their functional performances were measured and compared with the normal controls (NC). Multiple regression analyses investigated the associations between functional scores (Disability Assessment in Dementia) and clinical correlates (cognitive test scores, neuropsychiatric symptoms and motor signs) in the NC subjects and cognitively impaired subjects.
Results: Subjects with MCI had intermediate functional performance between the NC and those with VMD. Regression analyses revealed that lower scores of cognitive tests (delayed recall and categorical verbal fluency tests), apathy, aberrant motor symptoms and parkinsonism features were associated with lower functional scores in clinically non-demented subjects. Functional scores had no correlation with age, education and medical illness burden.
Conclusion: Neuropsychiatric symptoms and parkinsonism features were associated with functional impairment in the clinically non-demented elderly in the community. Assessment of these should be incorporated in the evaluation of older persons for early cognitive impairment.