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Background: The bidirectional association of HIV/AIDS and Tuberculosis (TB) presents significant global health challenges. However, the relationship between these dual epidemics and the heterogeneity in their mortality rate patterns have not been properly addressed. Therefore, the aim of this study was to cluster and model the joint trajectories of HIV/AIDS and TB mortality rates from 1990 to 2021 worldwide. Methods: In this longitudinal study, the HIV/AIDS and TB mortality rates data for 204 countries from 1990 to 2021 were obtained from the global burden of disease database. The longitudinal k-means clustering approach was utilized to categorize countries into homogeneous subgroups based on the joint patterns of HIV/AIDS and TB mortality rates. Subsequently, the Bayesian multi-process nonlinear Latent Growth Model (LGM) was conducted to concurrently estimate the patterns of HIV/AIDS and TB mortality rates. Results: The average global TB mortality rates dropped from 30.61 to 13.34 per 100,000 between 1990 and 2021. Meanwhile, the average HIV/AIDS mortality rates rose from 10.94 to 48.42 per 100,000 by 2000 before declining to 16.90 per 100,000 in 2021. The Bayesian multi-process nonlinear LGM indicated that the intercepts for the overall HIV/AIDS and TB models were 11.168 and 30.184, and the slopes were 16.104 and − 1.040, respectively. This suggests that the initial HIV/AIDS and TB mortality rates were 11.168 and 30.184 persons per 100,000, and the rates of change were 16.104 and − 1.040 persons per 100,000 every five years. However, the strength and direction of the rate of change were dependent on the factor loading scores, as they exhibited a nonlinear trend. Finally, the 204 countries were clustered into three distinct subgroups, each with different intercepts and slopes. Cluster A demonstrated the lowest HIV/AIDS and TB mortality rates throughout the study, while Cluster C exhibited the highest mortality rates. Conclusions: Although the overall global HIV/AIDS and TB mortality rates have declined, Southern African countries continue to bear a significant burden of HIV/AIDS and TB, with no significant reduction observed in TB mortality rates from 1990 to 2021. Therefore, prioritizing these countries is crucial to achieving the Sustainable Development Goals (SDGs) of eradicating the global HIV/AIDS and TB epidemics by 2030 and 2035, respectively. [ABSTRACT FROM AUTHOR]

Introduction: Low socioeconomic status (SES) is identified as a pivotal risk factor for mental health. Objective socioeconomic status (OSS) is measured by tangible resources, whereas subjective social status (SSS) reflects an individual's perception of their OSS. A paucity of literature exists that elucidates the specific psychosocial mechanisms or pathways linking OSS with mental illness via SSS. This research aimed to explore the mediating role of SSS in the OSS-mental health association, utilizing data from the Iranian Mental Health Survey (IranMHS). Methods: This study is a secondary analysis of data from IranMHS, a national survey conducted in 2011 through face-to-face interviews with 7,886 Iranian adults aged 15-64. As part of the original survey, the General Health Questionnaire-28 (GHQ-28) was randomly administered to half of these participants. We focused our analysis on data from 3,759 participants who completed all items of the GHQ-28. OSS was evaluated using education, occupation, wealth, and a combined OSS index, while SSS was measured using the MacArthur Scale. We examined how SSS mediates the associations between OSS factors and GHQ scores, including its four dimensions—somatic symptoms, anxiety and insomnia, social dysfunction, and severe depression— while adjusting for demographic variables and conducting gender-stratified analyses. Results: Among the 3759 respondents, 2157 (57.4%) were women, 2110 (56.1%) lived in urban areas, with an average age of 33.1 years (SD=12.1). SSS mediated the associations between wealth and the overall GHQ score (mediation percentage: 92.3%), education (75.4%), OSS index (66.7%), and occupation (34.0%) on the GHQ score. The most significant mediation effects were observed for wealth on the somatic symptoms, social dysfunction, and depression dimensions, with SSS accounting for more than 80% of these associations. Conclusion: The findings indicate a significant mediating role of SSS in the relationship between OSS and mental health. Enhancing our comprehension of the social determinants that moderate the relationship between objective and subjective socioeconomic status may contribute to a more nuanced understanding of the impact of SES on mental health outcomes. [ABSTRACT FROM AUTHOR]

Introduction: Neonatal hyperbilirubinemia is one of the most important factors affecting the auditory system and can cause sensorineural hearing loss. This study investigated the relationship between behavioral hearing thresholds in children with a history of jaundice and the maximum level of bilirubin concentration in the blood. Materials and Methods: This study was performed on 18 children with a mean age of 5.6 years and with a history of neonatal hyperbilirubinemia. Behavioral hearing thresholds, transient evoked emissions and brainstem evoked responses were evaluated in all children. Results: Six children (33.3 %) had normal hearing thresholds and the remaining (66.7 %) had some degree of hearing loss. There was no significant relationship (r= -0.28, P= 0.09) between the mean total bilirubin levels and behavioral hearing thresholds in all samples. A transient evoked emission was seen only in children with normal hearing thresholds however in eight cases brainstem evoked responses had not detected. Conclusion: Increased blood levels of bilirubin at the neonatal period were potentially one of the causes of hearing loss. There was a lack of a direct relationship between neonatal bilirubin levels and the average hearing thresholds which emphasizes on the necessity of monitoring the various amounts of bilirubin levels.

In many communications systems, data can be divided into different importance levels. For these systems, unequal error protection (UEP) techniques are used to guarantee lower BER for the more important classes. In particular, if the precise characteristics of the channel are not known, UEP can be used to recover the more important classes even in poor receiving conditions. In this paper, we derive bounds on the performance of unequal error protecting turbo codes. These bounds serve as an important tool in predicting the performance of these codes. In order to derive the bounds, we introduce the notion of UEP-uniform interleaver which is a random interleaver that does not change the order of classes in the turbo code frame. We also present a method to derive the weight enumerating function for UEP turbo codes. Index Terms--Turbo codes, unequal error protection, error bounds.

A major concern in designing communication systems is to maintain quality of service for a wide range of channel conditions. This is an important issue particularly for the applications where precise characterization of the channel is impossible. For such applications, the source data can be classified into several classes and Unequal Error Protection (UEP) can be used to effectively protect the more important classes even in poor receiving conditions. This paper is focused on the study, design, and performance evaluation of unequal error protecting turbo coded modulation schemes. We first propose several schemes for unequal error protecting using turbo coded modulation. All these schemes provide high performance gains for more important classes that can hardly be achieved using conventional coded modulation schemes. We then study unequal error protecting turbo coded modulation schemes by deriving channel capacity and cutoff rates for different protection levels. We show that for more important classes more room is available for improvement. Index Terms--Turbo coded modulation, unequal error protection.

We derive performance bounds for turbo-coded modulation systems over fading channels. We consider a Ricean fading channel model both with and without channel-state information (CSI). This model obviously includes Rayleigh fading channel as a special case. The bounds are extensions of similar bounds derived for additive white Gaussian noise channels. For the special case of a Rayleigh fading channel with CSI, we also derive a tighter version of the bound. We illustrate the use of the new bounds via some numerical examples. Index Terms: Error probability bounds, fading channels, parallel concatenated codes, turbo-coded modulation, turbo-codes.

In this paper we investigate the problem of designing reduced complexity detectors for multitrack high-density magnetic recording systems. The detectors derived in this work operate on superstate sets and carry several survivors for each set. We show that such a reduced state increased survivor approach provides near optimal performance to the maximum likelihood method, namely the Viterbi Algorithm (VA), but operate at a fractional complexity of the VA. Index Terms - Inter-track interference, multitrack multihead systems.

In this paper multistage trellis-coded vector quantization (MS-TCVQ) is developed as a constrained trellis source-coding technique. The performance of the two-stage TCVQ is studied for Gaussian sources. Issues of stage-by-stage design, output alphabet selection, and complexity are addressed with emphasis on selecting and partitioning the stage codebooks. For a given rate, MS-TCVQ achieves low encoding and storage complexity compared to TCVQ, and comparisons with same-dimensional multistage vector quantization indicate a 0.5-3-dB improvement in signal-to-quantization-noise ratio. Index Terms - Data compression, residual quantizers, trellis-coded vector quantization (TCVQ), vector quantization.

We derive a new upper bound on the word- and bit-error probabilities of turbo codes with maximum-likelihood decoding by using the Gallager bound. Since the derivation of the bound for a given interleaver is intractable, we assume uniform interleaving as in the derivation of the standard union bound for turbo codes [1], [2]. The result is a generalization of the transfer function bound and remains useful for a wider range of signal-to-noise ratios, particularly for some range below the channel cutoff rate. The new bound is also applicable to other linear codes. Index Terms - Error bounds, Gallager bound, parallel concatenated codes, performance bounds, turbo codes, union bound.

We study the decentralized detection problem in a general framework where arbitrary number of quantization levels at the local sensors are allowed, and transmission from the sensors to the fusion center is subject to both noise and interchannel interference. We treat both Bayesian and Neyman-Pearson approaches to the problem, and develop an iterative descent algorithm to design the optimal quantizers and fusion rule. Some numerical examples for both approaches are also presented.