224 research outputs found
Inferences in the Interval Censored Exponential Regression Model
The problem of estimation when the data are interval censored has been investigated by several authors. Lindsey and Ryan (1998) considered the application of conventional methods to interval mid (or end) points and showed that they tended to underestimate the standard errors of the estimated parameters and give potentially misleading results. MacKenzie (1999) and Blagojevic (2002) conjectured that the estimator of the parameter was artificially precise when analyzing inspection times as if they were exact when the "time to event" data followed an exponential distribution. In this thesis, we derive formulae for pseudo and true (or exact) likelihoods in the exponential regression model in order to examine the consequences for inference on parameters when the pseudo-likelihood is used in place of the true likelihood. We pay particular attention to the approximate bias of the maximum likelihood estimates in the case of the true likelihood. In particular we present analytical work which proves that the conjectures of Lindsey and Ryan (1998), MacKenzie (1999) and Blagojevic (2002) hold, at least for the exponential distribution with categorical or continuous covariates.We undertake a simulation study in order to quantify and analyze the relative performances of maximum likelihood estimation from both likelihoods. The numerical evidence suggests that the estimates from true likelihood are more accurate. We apply the proposed method to a set of real interval-censored data collected in a Medical Research Council (MRC, UK) multi-centre randomized controlled trial of teletherapy in the age-related macular disease (the ARMD) study.Master of Science (MS
Analisis Kebijakan Pemerintah Terkait Ancaman Penggangguran Pasca Kenaikan Inflasi di Kota Bogor
Inflation and unemployment are the two main problems in the economy, when inflation increases, the prices of goods and wages do not move at the same pace. high inflation and unemployment have a negative impact on the economy and stability of the country. He also stated that if inflation is high, unemployment will be low. This study uses a sample of inflation and unemployment rates in Bogor City in 2019-2021 based on the Central Statistics Agency. The analytical method used is descriptive analysis. The results of this study are the influence of low unemployment has a positive impact on the economy and workers, unemployment that is too low can push inflation up. But if the government takes steps to curb inflation, it could reduce unemployment and trigger a recession.
Ocular manifestations and pathology of adult T-cell leukemia/lymphoma associated with human T-lymphotropic virus type 1
The human T-cell lymphotropic virus type 1 (HTLV-1), endemic in defined geographical areas around the world, is recognized as the etiologic agent of adult T-cell leukemia/lymphoma (ATL), or HTLV-1. ATL is a rare adult onset T-cell malignancy that is characterized by the presence of ATL flower cells with T-cell markers, HTLV-1 antibodies in the serum, and monoclonal integration of HTLV-1 provirus in affected cells. Ocular manifestations associated with HTLV-1 virus infection have been reported and include HTLV-1 uveitis and keratoconjunctivitis sicca, but reports of ocular involvement in ATL are exceedingly rare. This article describes the ocular manifestations and pathology of ATL. We also report for the first time a case of a 34-year-old male with systemic ATL and prominent atypical lymphoid cell infiltration in the choroid. To our knowledge, this is the first report defining prominent choroidal involvement as a distinct ocular manifestation of ATL. ATL may masquerade as a variety of other conditions, and molecular techniques involving microdissection and PCR have proven to be critical diagnostic tools. International collaboration will be needed to better understand the presentation and diagnosis of this rare malignancy
Ocular pathology of uncommon hematologic malignancies: a case series
<p>Abstract</p> <p>Introduction</p> <p>In general, ocular complications of hematologic malignancies such as leukemia are well documented. However, reports of ocular involvement in such diseases as lymphomatoid granulomatosis and chronic myelomonocytic leukemia are uncommon. Here we present cases of these two relatively rare hematologic malignancies demonstrating clinical and subclinical ocular involvement.</p> <p>Case Presentation</p> <p>In the first case, a 54-year-old man with a previous diagnosis of lymphomatoid granulomatosis presented with a new-onset conjunctival lesion while his systemic disease was thought to be in remission. A biopsy was taken that revealed heavy infiltrates of B and T cells at the site of the lesion. Molecular analysis confirmed that these cells were positive for both Epstein-Barr viral DNA and immunoglobulin heavy chain gene rearrangement, consistent with a manifestation of his systemic disease. In the second case, a 51-year-old man with chronic myelomonocytic leukemia died after a waxing and waning clinical course. Post-mortem studies revealed the presence of atypical monocytes in the choroidal and subretinal spaces, consistent with his previous diagnosis.</p> <p>Conclusion</p> <p>While ocular involvement in hematologic malignancies is not uncommon, these two cases describe involvement of the eye by two relatively rare neoplasms. We herein emphasize novel findings in each case, including conjunctival involvement as the first sign of recurrent lymphomatoid granulomatosis and the combination of subretinal and choroidal myelomonocytic leukemic infiltration. With the evolution of new antineoplastic therapies that may prolong life, these cases exemplify the importance of eye care in patients diagnosed with hematologic malignancies.</p
Evaluation of the volumetric erosion of spherical electrical contacts using the defect removal method
Responses of Multipotent Retinal Stem Cells to IL-1 β
Purpose. To investigate how multipotent retinal stem cells (RSCs) isolated from mice respond to the proinflammatory signaling molecules, IL-1β, IL-18, and IL-17A. Materials and Methods. RSCs were cultured in a specific culture medium and were treated with these cytokines. Cell viability was detected by MTT assay; ultrastructure was evaluated by transmission electron microscopy; expression of IL-17rc and proapoptotic proteins was detected by immunocytochemistry and expression of Il-6 and Il-17a was detected by quantitative RT-PCR. As a comparison, primary mouse retinal pigment epithelium (RPE) cells were also treated with IL-1β, IL-18, or IL-17A and analyzed for the expression of Il-6 and Il-17rc. Results. Treatment with IL-1β, IL-18, or IL-17A decreased RSC viability in a dose-dependent fashion and led to damage in cellular ultrastructure including pyroptotic and/or necroptotic cells. IL-1β and IL-18 could induce proapoptotic protein expression. All treatments induced significantly higher expression of Il-6 and Il-17rc in both cells. However, neither IL-1β nor IL-18 could induce Il-17a expression in RSCs. Conclusions. IL-1β, IL-18, and IL-17A induce retinal cell death via pyroptosis/necroptosis and apoptosis. They also provoke proinflammatory responses in RSCs. Though IL-1β and IL-18 could not induce Il-17a expression in RSCs, they both increase Il-17rc expression, which may mediate the effect of Il-17a
Activation of STING Based on Its Structural Features
The cGAS-cGAMP-STING pathway is an important innate immune signaling cascade responsible for the sensing of abnormal cytosolic double-stranded DNA (dsDNA), which is a hallmark of infection or cancers. Recently, tremendous progress has been made in the understanding of the STING activation mechanism from various aspects. In this review, the molecular mechanism of activation of STING protein based on its structural features is briefly discussed. The underlying molecular mechanism of STING activation will enable us to develop novel therapeutics to treat STING-associated diseases and understand how STING has evolved to eliminate infection and maintain immune homeostasis in innate immunity
Pressure-induced quantum phase transitions in topological insulator YbB6
Topological insulators (TIs) containing 4f electrons have recently attracted
intensive interests due to the possible interplay of their non-trivial
topological properties and strong electronic correlations. YbB6 and SmB6 are
the prototypical systems with such unusual properties, which may be tuned by
external pressure to give rise to new emergent phenomena. Here, we report the
first observation, through in-situ high pressure resistance, Hall, X-ray
diffraction and X-ray absorption measurements, of two pressure-induced quantum
phase transitions (QPTs) in YbB6. Our data revealthat the two insulating phases
are separated by a metallic phase due to the pressure-driven valence change of
Yb f-orbitals. In combination with previous studies, our results suggest that
the two insulating states may be topologically different in nature and
originate from the d-p and d-f hybridization, respectively. The tunable
topological properties of YbB6 revealed in this study may shed light on the
intriguing correlation between the topology and the 4f electrons from the
perspective of pressure dependent studies.Comment: 18 pages, 5 figure
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