1,493 research outputs found
Altered Circulating Follicular Helper T Cell Phenotype In Systemic Lupus Erythematosus
Autoreactive B cells in Systemic Lupus Erythematosus (SLE) undergo autoantigen selection, suggesting a requirement for germinal center follicular helper T (Tfh) cells in their maturation. However, evidence for dysregulation of Tfh cells in SLE and their contribution to disease activity remains unclear. Recently, blood CXCR5hi CD4 T cells, a heterogeneous pool consisting of functionally distinct Th1-, Th2-, Th17-like subsets, have been proposed to be the circulating counterpart of Tfh cells. The purpose of this study was to examine the hypothesis that Tfh dysregulation, as reflected in altered phenotype of blood CXCR5hi population, was associated with SLE disease activity. Blood samples from 49 clinically well-characterized SLE patients, 28 Behçet\u27s disease (BD) patients as autoimmune disease control and 16 healthy controls were included. Expression of key Tfh surface receptors (ICOS, inducible T-cell co-stimulator; PD-1, programmed cell death protein-1) as well as composition of T helper subtypes within the circulating CXCR5hi compartment were enumerated by flow-cytometry. The phenotype of blood CXCR5hi cells was correlated with clinical history and B cell phenotype. SLE patients had significant expansion of circulating Tfh-like CD4 T cells (CXCR5hiICOShiPD-1hi) when compared to controls (p \u3c 0.001). Interestingly, PD-1 mean florescence intensity (MFI) was markedly elevated in blood CXCR5hi subset of SLE patients when compared to controls (p \u3c 0.001). PD-1 MFI in the CXCR5hi population correlated significantly with SLE disease activity index (SLEDAI; Spearman r = 0.43, p = 0.03), blood plasmablast expansion (Spearman r = 0.34, p = 0.02), and high anti-dsDNA antibody titers (p = 0.004). Blood CXCR5hiPD-1hi cells phenotypically resembled pre- or post-germinal center Tfh cells, with increased percentage of IL-21 producers (p = 0.02), lower CCR7 MFI (p = 0.03) when compared to CXCR5hiPD-1lo subset, and low Bcl-6 expression. Compared to BD patients, SLE patients had an increase in the CXCR5hi Th2 subset (p \u3c 0.05) and a decrease in the Th17 (p \u3c 0.001) subsets. The expansion of the CXCR5hi Th2 subset was also positively associated with SLEDAI scores. Our results demonstrate that altered phenotype and subset composition of blood Tfh-like cells is correlated with disease activity in lupus patients, suggesting a potential role of GC Tfh dysregulation in the pathogenesis of human SLE
Longitudinal Trauma Treatment Outcomes in an Immigrant and Refugee Sample
Refugee and immigrant populations are at an increased risk of having posttraumatic stress disorder (PTSD) and exhibit a significant amount of variance in trauma treatment outcomes that may be impacted by sociocultural factors. This study examines the impact of demographic variables on treatment outcome and trajectory of PTSD symptoms in a clinic setting with trauma-focused treatments in refugee/immigrant and general populations. Data was collected from the electronic medical record at the Harborview Center for Sexual Assault and Traumatic Stress. A total of 817 participants completed intake, 58 of which self-identified as immigrant/refugee. One-way ANOVAs were conducted to examine group differences of sociocultural factors including income status, prior mental health history, and social support. Significant differences in baseline symptom and last symptom monitor were found for different sociocultural factors. Hierarchical multiple regression was conducted to examine effect of counseling visits on treatment outcome while controlling for baseline PTSD symptom. PTSD baseline symptom was significant in predicting 19.2% of variance in treatment outcome (R2 = 0.19; p \u3c 0.001) while counseling visits did not add significant variance to the model. One-way ANOVA was conducted to examine the baseline symptoms between immigrant/refugee and non-immigrant/non-refugee groups. No significant difference was found for baseline symptoms between groups, but difference was found with last symptom monitor where immigrant/refugee group had higher mean symptom score (x̄ = 26.03 for immigrant/refugee and x̄ = 21.65 for others). Hierarchical linear modeling was used to analyze the trend of symptom progression. Results showed decrease of symptoms with flattening of the curve over time with no difference in progression for immigrant/refugee group. Distress level was different at baseline for different language groups. No significant differences were found in symptom progression with different language or education groups. Post-hoc analyses were conducted with results showing different symptom trajectory for income groups. Different baselines were found with different social support groups. For immigrant/refugee group, different trajectory was found in different language groups. Overall, sociocultural factors impact the trajectory of treatment differently. Addressing access to care with different barriers including language, social support network, and income status is important when considering treatment provision for immigrant/refugee
Capacity Analysis of Linear Operator Channels over Finite Fields
Motivated by communication through a network employing linear network coding,
capacities of linear operator channels (LOCs) with arbitrarily distributed
transfer matrices over finite fields are studied. Both the Shannon capacity
and the subspace coding capacity are analyzed. By establishing
and comparing lower bounds on and upper bounds on , various
necessary conditions and sufficient conditions such that are
obtained. A new class of LOCs such that is identified, which
includes LOCs with uniform-given-rank transfer matrices as special cases. It is
also demonstrated that is strictly less than for a broad
class of LOCs. In general, an optimal subspace coding scheme is difficult to
find because it requires to solve the maximization of a non-concave function.
However, for a LOC with a unique subspace degradation, can be
obtained by solving a convex optimization problem over rank distribution.
Classes of LOCs with a unique subspace degradation are characterized. Since
LOCs with uniform-given-rank transfer matrices have unique subspace
degradations, some existing results on LOCs with uniform-given-rank transfer
matrices are explained from a more general way.Comment: To appear in IEEE Transactions on Information Theor
On Linear Operator Channels over Finite Fields
Motivated by linear network coding, communication channels perform linear
operation over finite fields, namely linear operator channels (LOCs), are
studied in this paper. For such a channel, its output vector is a linear
transform of its input vector, and the transformation matrix is randomly and
independently generated. The transformation matrix is assumed to remain
constant for every T input vectors and to be unknown to both the transmitter
and the receiver. There are NO constraints on the distribution of the
transformation matrix and the field size.
Specifically, the optimality of subspace coding over LOCs is investigated. A
lower bound on the maximum achievable rate of subspace coding is obtained and
it is shown to be tight for some cases. The maximum achievable rate of
constant-dimensional subspace coding is characterized and the loss of rate
incurred by using constant-dimensional subspace coding is insignificant.
The maximum achievable rate of channel training is close to the lower bound
on the maximum achievable rate of subspace coding. Two coding approaches based
on channel training are proposed and their performances are evaluated. Our
first approach makes use of rank-metric codes and its optimality depends on the
existence of maximum rank distance codes. Our second approach applies linear
coding and it can achieve the maximum achievable rate of channel training. Our
code designs require only the knowledge of the expectation of the rank of the
transformation matrix. The second scheme can also be realized ratelessly
without a priori knowledge of the channel statistics.Comment: 53 pages, 3 figures, submitted to IEEE Transaction on Information
Theor
IoT-Based Fire Safety System Using MQTT Communication Protocol
Fire can be made useful for various purposes. However, uncontrollable fire may result in property damage and human death. The major factor of fire deaths is due to excessive smoke inhalation. Therefore, early detection of fire is crucial in fire detection systems. The conventional fire detection system does not come with a false alarm prevention system. Besides, the system is unable to tell the exact location of the fire. In this project, an Internet of Things (IoT) based fire safety system is developed to overcome these problems. The proposed system consists of three major parts which are the detector, processing unit and surveillance. The detector unit is an integration of ESP32, carbon monoxide sensor, ionization smoke detector, buzzer, temperature and humidity sensor. As the processing unit, Raspberry Pi is used to run the Node-RED application, which processes the data and performs monitoring. The communication between the detector and processing unit is based on the Message Queuing Telemetry Transport (MQTT) protocol. A surveillance unit is where a camera is installed to monitor the condition of the surrounding. The response of the system is based upon the sensor’s values or the user’s response. Once the fire breakout is confirmed, the system will immediately sound the alarm, and Global Positioning System (GPS) coordinates and floor plan of the accommodation will send to the nearby fire station. The floor plan is developed to track the exact location of the fire. Experiments are carried out on the proposed fire safety system, and encouraging results are produced
P-glycoprotein efflux transporter: a key to pharmacokinetic modeling for methadone clearance in fetuses
Naaloss: Rethinking the objective of speech enhancement
Reducing noise interference is crucial for automatic speech recognition (ASR)
in a real-world scenario. However, most single-channel speech enhancement (SE)
generates "processing artifacts" that negatively affect ASR performance. Hence,
in this study, we suggest a Noise- and Artifacts-aware loss function, NAaLoss,
to ameliorate the influence of artifacts from a novel perspective. NAaLoss
considers the loss of estimation, de-artifact, and noise ignorance, enabling
the learned SE to individually model speech, artifacts, and noise. We examine
two SE models (simple/advanced) learned with NAaLoss under various input
scenarios (clean/noisy) using two configurations of the ASR system
(with/without noise robustness). Experiments reveal that NAaLoss significantly
improves the ASR performance of most setups while preserving the quality of SE
toward perception and intelligibility. Furthermore, we visualize artifacts
through waveforms and spectrograms, and explain their impact on ASR
An Intermediate in the evolution of superfast sonic muscles
Background
Intermediate forms in the evolution of new adaptations such as transitions from water to land and the evolution of flight are often poorly understood. Similarly, the evolution of superfast sonic muscles in fishes, often considered the fastest muscles in vertebrates, has been a mystery because slow bladder movement does not generate sound. Slow muscles that stretch the swimbladder and then produce sound during recoil have recently been discovered in ophidiiform fishes. Here we describe the disturbance call (produced when fish are held) and sonic mechanism in an unrelated perciform pearl perch (Glaucosomatidae) that represents an intermediate condition in the evolution of super-fast sonic muscles.
Results
The pearl perch disturbance call is a two-part sound produced by a fast sonic muscle that rapidly stretches the bladder and an antagonistic tendon-smooth muscle combination (part 1) causing the tendon and bladder to snap back (part 2) generating a higher-frequency and greater-amplitude pulse. The smooth muscle is confirmed by electron microscopy and protein analysis. To our knowledge smooth muscle attachment to a tendon is unknown in animals.
Conclusion
The pearl perch, an advanced perciform teleost unrelated to ophidiiform fishes, uses a slow type mechanism to produce the major portion of the sound pulse during recoil, but the swimbladder is stretched by a fast muscle. Similarities between the two unrelated lineages, suggest independent and convergent evolution of sonic muscles and indicate intermediate forms in the evolution of superfast muscles
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