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Recent work incorporates pre-trained word embeddings such as BERT embeddings into Neural Topic Models (NTMs), generating highly coherent topics. However, with high-quality contextualized document representations, do we really need sophisticated neural models to obtain coherent and interpretable topics? In this paper, we conduct thorough experiments showing that directly clustering high-quality sentence embeddings with an appropriate word selecting method can generate more coherent and diverse topics than NTMs, achieving also higher efficiency and simplicity., Comment: Accepted by NAACL 2022

Estimating population counts for multidimensional tables based on a representative sample subject to known marginal population counts is not only important in survey sampling but is also an integral part of standard methods for simulating area-specific synthetic populations. In this article several estimation methods are reviewed, with particular focus on the iterative proportional fitting procedure and the maximum likelihood method. The performance of these methods is investigated in a simulation study for multidimensional tables, as previous studies are limited to 2 by 2 tables. The data are generated under random sampling but also under misspecification models, for which sample and target populations differ systematically. The empirical results show that simple adjustments can lead to more efficient estimators, but generally, at the expense of increased bias. The adjustments also generally improve coverage of the confidence intervals. The methods discussed in this article along with standard error estimators, are made freely available in the R package mipfp. As an illustration, the methods are applied to the 2011 Australian census data available for the Illawarra Region in order to obtain estimates for the desired three-way table for age by sex by family type with known marginal tables for age by sex and for family type.

Acne vulgaris is a common inflammatory skin disorder which is recognizable by dermatological lesions and scars. In addition to some pathogenetic factors such as hyperkeratinization, upregulated sebum secretion, and immunoinflammatory reactions, recent studies have also connected oxidative stress to the pathogenesis of acne vulgaris. In this article, we will briefly review clinical studies that interrogated alterations in oxidative stress biomarkers by a systematic search conducted in PubMed, Web of Science, and Scopus using “acne”, “oxidative stress”, and “reactive oxygen species” keywords. Overall, studies have shown that oxidative biomarkers (e.g. lipid peroxidation final products) are higher in acne vulgaris lesions. A significant positive correlation has also been noted between acne severity and oxidative biomarkers. In contrast, diminished levels of antioxidant enzymes (e.g. superoxide dismutase and catalase) have been observed in acne. We propose four probable mechanisms for the role of reactive oxygen species (ROS) in acne pathogenesis. We believe that ROS can contribute significantly to the acne vulgaris pathobiology via toll-like receptor (TLR), peroxisome proliferator-activated receptor (PPAR), mTOR pathway, and innate immune system, resulting in inflammation by alterations in the generation of several proinflammatory cytokines including IL-1, IL-8, and TNF-a.[GMJ. 2019;8:e1291]

Household relocation modelling is an integral part of the Government planning process as residential movements influence the demand for community facilities and services. This study will address the problem of modelling residential relocation choice by estimating a logit-link class model. The proposed model estimates the probability of an event which triggers household relocation. The attributes considered in this study are: requirement for bedrooms, employment status, income status, household characteristics, and tenure (i.e. duration living at the current location). Accurate prediction of household relocations for population units should rely on real world observations. In this study, a longitudinal survey data gathered in the Household, Income and Labour Dynamics in Australia (HILDA) program is used for modelling purposes. The HILDA dataset includes socio-demographic information such as general health situation and well-being, lifestyle changes, residential mobility, income and welfare dynamics, and labour market dynamics collected from the sampled individuals and households. The technique presented in this paper links possible changes in households' socio-demographic characteristics to the probability of residential relocation by developing a mixed effects discrete-choice logit model (MEDCLM) for longitudinal binary data using the HILDA dataset. The proposed model captures the effect of repeated measurements together with the area-specific random effects.

To achieve greater transit-time reduction and improvement in reliability of transport services, there is an increasing need to assist transport planners in understanding the value of punctuality; i.e. the potential improvements, not only to service quality and the consumer but also to the actual profitability of the service. In order for this to be achieved, it is important to understand the network-specific aspects that affect both the ability to decrease transit-time, and the associated cost-benefit of doing so. In this paper, we outline a framework for evaluating the effectiveness of proposed changes to average transit-time, so as to determine the optimal choice of average arrival time subject to desired punctuality levels whilst simultaneously minimizing operational costs. We model the service transit-time variability using a truncated probability density function, and simultaneously compare the trade-off between potential gains and increased service costs, for several commonly employed cost-benefit functions of general form. We formulate this problem as a constrained optimization problem to determine the optimal choice of average transit time, so as to increase the level of service punctuality, whilst simultaneously ensuring a minimum level of cost-benefit to the service operator.

Generating a reliable computer-simulated synthetic population is necessary for knowledge processing and decision-making analysis in agent-based systems in order to measure, interpret and describe each target area and the human activity patterns within it. In this paper, both synthetic reconstruction (SR) and combinatorial optimisation (CO) techniques are discussed for generating a reliable synthetic population for a certain geographic region (in Australia) using aggregated- and disaggregated-level information available for such an area. A CO algorithm using the quadratic function of population estimators is presented in this paper in order to generate a synthetic population while considering a two-fold nested structure for the individuals and households within the target areas. The baseline population in this study is generated from the confidentialised unit record files (CURFs) and 2006 Australian census tables. The dynamics of the created population is then projected over five years using a dynamic micro-simulation model for individual- and household-level demographic transitions. This projection is then compared with the 2011 Australian census. A prediction interval is provided for the population estimates obtained by the bootstrapping method, by which the variability structure of a predictor can be replicated in a bootstrap distribution.

Background. Alopecia areata (AA) is a chronic inflammatory disease of the hair follicle. The exact pathogenesis of AA remains unknown, although recent studies support a T-cell mediated autoimmune process. On the other hand, some studies have proposed that the renin-angiotensin-aldosterone system (RAAS) may play a role in autoimmunity. Therefore, we assessed serum activity of angiotensin converting enzyme (ACE), a component of this system, in AA. Methods. ACE activity was measured in the sera of 19 patients with AA and 16 healthy control subjects. In addition, the relationship between severity and duration of the disease and ACE activity was evaluated. Results. Serum ACE activity was higher in the patient group (55.81 U/L) compared to the control group (46.41 U/L), but the difference was not statistically significant (P=0.085). Also, there was no correlation between ACE activity and severity (P=0.13) and duration of disease (P=0.25) in the patient group. Conclusion. The increased serum ACE activity found in this study may demonstrate local involvement of the RAAS in the pathogenesis of AA. Assessment of ACE in a study with a larger sample size as well as in tissue samples is recommended in order to further evaluate the possible role of RAAS in AA.

Psoriasis is an inflammatory disorder characterized by a T helper cell type 1 cytokine pattern. Interferon-gamma (IFN-γ), tumor necrosis factor-alpha (TNF-α), interleukin-2 (IL-2) and interleukin-1 (IL-1) are predominantly ex-pressed in this disorder. This immunological pathway is stimulated by interleukin-12 (IL-12) released from activated dendritic cells and by exposure of T cells to type 1 cytokines during maturation.

In this clinical image, we present the picture of a diabetic patient with rubeosis faciei diabeticorum, a relatively common, but usually unnoticed, microangiopathic complication of diabetes mellitus that could herald other more notorious microangiopathic complications of diabetes mellitus, such as retinopathy. This case will help other physicians to consider rubeosis faciei diabeticorum whenever they face similar cases.

Sir, Vitiligo is an acquired skin depigmentation disorder affecting 1% of the world population.[1] Pathogenesis of vitiligo is complex and not yet fully understood. Oxidative stress has been proposed to be one of the major players in the pathogenesis of vitiligo.[1,2] Glucose-6-phophate dehydrogenase (G6PD) is one of the main antioxidant enzymes in the body.[3] The low erythrocyte levels of this enzyme have been shown to be a reliable indicator of oxidative stress.[3] The aim of this study was to evaluate the role of oxidative stress in the pathogenesis of vitiligo by comparing the erythrocyte levels of G6PD between vitiligo patients and healthy controls. In this IRB-approved two-group cross-sectional comparative study, 30 patients with vitiligo were enrolled as cases. Of these 30 patients, 25 had generalized and 5 had segmental vitiligo. Exclusion criteria were receiving treatment for vitiligo within the past 3 months before enrollment, history of any other systemic disorder, history of drug or alcohol dependency or cigarette smoking, and use of one of certain specified medications within 1 month before enrollment (corticosteroids, non-steroidal anti-inflammatory drugs, and antioxidant supplements). Thirty age and sex matched healthy subjects were also enrolled as controls. After giving informed consent, venous blood samples were obtained from all cases and controls. Erythrocyte G6PD levels were measured by Beutler's method.[4] Statistical analyses were performed using the SPSS base 16. Quantitative data were compared between two groups using Mann-Whitney U Test; categorical data were compared using the chi-square test. P < 0.05 was considered to be statistically significant. Cases and controls were similar in terms of age (39.3 ± 12.8 vs. 39.5 ± 12.3 years, P = 0.9) and sex (male/female ratio=1 in both groups, P = 1.0). The erythrocyte G6PD levels were significantly lower in vitiligo patients compared to controls (12.5 ± 5.4 U/g Hb vs. 16.6 ± 3.3 U/g Hb, P = 0.003). However, erythrocyte G6PD levels were similar between generalized and segmental vitiligo patients (12.8 ± 6.1 U/g Hb vs. 14.4 ± 2.9 U/gr Hb; P = 0.6). Oxidative stress is increasingly considered as one of the major players in the pathogenesis of vitiligo.[1,2] Several studies have demonstrated the increased levels of oxidative stress markers like malondialdehyde (MDA) and decreased levels of anti-oxidant factors like superoxide dismutase in vitiligo patients.[1,4] In two previous studies from India and Turkey, the levels of G6PD, one of the major antioxidant enzymes, have also been shown to be significantly lower in patients with vitiligo compared with healthy controls.[4,5] Similarly, in our study, the cellular levels of G6PD were significantly lower in vitiligo patients compared with healthy controls. Moreover, in our study, the cellular levels of G6PD were similar between patients with segmental and generalized vitiligo. Similarly, in a study by Akoglue et al.,[6] patients with generalized and segmental vitiligo had similar total oxidant and antioxidant statuses. In conclusion, the results of our study in accordance with previous studies show that vitiligo patients have lower levels of the antioxidant enzyme, G6PD. Larger studies on vitiligo patients with different demographic backgrounds are needed to further evaluate the role of oxidative stress in the pathogenesis of this enigmatic disorder.

A 47-year-old, otherwise healthy woman presented with multiple deep ulcers located primarily on her lower extremities that presented 6 days ago as blisters. A biopsy revealed livedoid vasculopathy, without any evidence of vasculitis. Extensive laboratory workup was positive only for type II cryoglobulins.