356 research outputs found
Mechanisms for human genomic rearrangements
Genomic rearrangements describe gross DNA changes of the size ranging from a couple of hundred base pairs, the size of an average exon, to megabases (Mb). When greater than 3 to 5 Mb, such changes are usually visible microscopically by chromosome studies. Human diseases that result from genomic rearrangements have been called genomic disorders. Three major mechanisms have been proposed for genomic rearrangements in the human genome. Non-allelic homologous recombination (NAHR) is mostly mediated by low-copy repeats (LCRs) with recombination hotspots, gene conversion and apparent minimal efficient processing segments. NAHR accounts for most of the recurrent rearrangements: those that share a common size, show clustering of breakpoints, and recur in multiple individuals. Non-recurrent rearrangements are of different sizes in each patient, but may share a smallest region of overlap whose change in copy number may result in shared clinical features among different patients. LCRs do not mediate, but may stimulate non-recurrent events. Some rare NAHRs can also be mediated by highly homologous repetitive sequences (for example, Alu, LINE); these NAHRs account for some of the non-recurrent rearrangements. Other non-recurrent rearrangements can be explained by non-homologous end-joining (NHEJ) and the Fork Stalling and Template Switching (FoSTeS) models. These mechanisms occur both in germ cells, where the rearrangements can be associated with genomic disorders, and in somatic cells in which such genomic rearrangements can cause disorders such as cancer. NAHR, NHEJ and FoSTeS probably account for the majority of genomic rearrangements in our genome and the frequency distribution of the three at a given locus may partially reflect the genomic architecture in proximity to that locus. We provide a review of the current understanding of these three models
Implementing Polar Projections with OGC Services for the Enhancement of AIRS NRT Visualization in LANCE
The Atmospheric Infrared Sounder (AIRS) NRT product is one important element in the Land, Atmosphere Near real-time Capability for EOS (LANCE). The LANCE processing of AIRS NRT products and the image generation are performed at the NASA Goddard Earth Sciences Data and Information Services Center (GES DISC). The Open Geospatial Consortium (OGC) services are being utilized to access AIRS NRT images. The ongoing AIRS NRT imagery enhancement work includes adding a new set of the images in polar projections. Polar projections are commonly used for mapping Antarctica and Arctic regions. We have implemented more precise south polar (EPSG:3031) projection and north polar (EPSG:3413) projection making our OGC service instances more useful and interoperable. Thus, AIRS NRT data can be easily accessed and integrated with other applications. It greatly increases the impact of our data on researches in polar regions.In this presentation, we will introduce the optimized processing workflow for OGC services from data access with spatial-temporal index to data visualization with different SLD, and demonstrate how to use open source software to provide more precise map images in polar projections
Global existence of solutions for fuzzy second-order differential equations under generalized H-differentiability
AbstractIn this paper, we study the global existence of solutions for second-order fuzzy differential equations with initial conditions under generalized H-differentiability. Second derivative of the H-difference of two functions under generalized H-differentiability is obtained. Two theorems which assure global existence of solutions for second-order fuzzy differential equations are given and proved. Some examples are given to illustrate these results
A tumor-like renal arteriovenous malformation on 18F-PSMA-1007 PET/CT: a case report
BackgroundRenal arteriovenous malformations (rAVMs) are congenital abnormal pathways between renal arteries and veins that are rare in the general population. It is often misdiagnosed as malignant renal tumors with abundant blood supply, and the definitive diagnosis primarily relies on angiography. Multimodality imaging, including contrast-enhanced computed tomography (CT), magnetic resonance imaging (MRI), and positron emission tomography (PET)/CT plays an important role in the differential diagnosis of renal space-occupying lesions.Case presentationA 56-year-old man presented with abdominal distension, loss of appetite, and back pain without obvious cause 2 years ago, without nausea vomiting, or frequent urination. Gastroscopy and colonoscopy showed multiple polyps in the duodenum and colon. Abdomen contrast-enhanced CT revealed a mass of 1.6 × 1.4 cm in the left kidney, which was considered to be a malignant tumor. PET/CT was performed for further diagnosis; the 18F-fluorodesoxyglucose (18F-FDG) PET/CT scan showed mild uptake in the left renal mass, while no uptake of 18F- prostate-specific membrane antigen (PSMA) was observed. Following a multidisciplinary discussion, the possibility of renal AVMs was considered and subsequently confirmed by renal angiography as the diagnosis. Then, selective segmental renal artery embolization was performed for treatment.ConclusionRenal AVMs are extremely rare in clinical practice. Due to limited research on the application of 18F-FDG and 18F-PSMA PET/CT to renal AVMs, its role remains largely unexplored. With the increasing popularity of PET/CT imaging, comprehensive imaging of the disease has become indispensable. We report the first case of PSMA PET/CT imaging in renal AVMs, and when PSMA expression is absent in a renal mass, the possibility of renal AVMs should be considered
Reinforcement Learning Based Gasoline Blending Optimization: Achieving More Efficient Nonlinear Online Blending of Fuels
The online optimization of gasoline blending benefits refinery economies.
However, the nonlinear blending mechanism, the oil property fluctuations, and
the blending model mismatch bring difficulties to the optimization. To solve
the above issues, this paper proposes a novel online optimization method based
on deep reinforcement learning algorithm (DRL). The Markov decision process
(MDP) expression are given considering a practical gasoline blending system.
Then, the environment simulator of gasoline blending process is established
based on the MDP expression and the one-year measurement data of a real-world
refinery. The soft actor-critic (SAC) DRL algorithm is applied to improve the
DRL agent policy by using the data obtained from the interaction between DRL
agent and environment simulator. Compared with a traditional method, the
proposed method has better economic performance. Meanwhile, it is more robust
under property fluctuations and component oil switching. Furthermore, the
proposed method maintains performance by automatically adapting to system
drift.Comment: 30 pages,13 figure
Experimental study on abnormal thyroid function in patients with Hashimoto's Thyroiditis caused by interference of thyroid hormone autoantibodies
Introduction: Thyroid hormone autoantibody (THAAb) is one of the important factors affecting the measurement of thyroid function. By studying the results of a patient suffered with Hashimoto's thyroiditis, we fully communicated with the clinician, looked for reasons, and achieved the purpose of restoring the truth and sorting out solutions.
Material and Methods: During routine examination by ADVIA-Centaur XP system, we found the test of a case was inconsistent with her clinical manifestations, with abnormal elevation of free thyroxine (FT4) that did not conform to the rule of the hypothalamic-pituitary-thyroid axis. Then, different platforms and demonstration of THAAbs with polyethylene glycol (PEG) precipitation were performed to eliminate the influence of THAAbs.
Results: The results showed that the thyroid function of the patient was consistent with the clinical manifestations and conformed to the law of the hypothalamic-pituitary-thyroid axis at Architect-i2000sr platform and Roche-Cobas-601 system. The content of FT4 was significantly reduced and lower than the normal reference range, after the patients' serum was treated with PEG, which was in line with the clinical practice. The serum THAAb titer of the patients was nearly 100 times higher than that of the control group.
Conclusions: Once the thyroid function of the patients do not conform to their own laws and clinical manifestations, laboratory staff should consider the interference of THAAbs. It is necessary to change the detection platform and retest the serum after PEG treatment while communicating with the clinicians, which is of great significance to provide a true and accurate result to clinicians and patients
Entrained flow gasification of coal/bio-oil slurries
Coal/bio-oil slurry (CBS) is a new partial green fuel for bio-oil utilization. CBS reacts with gasification agents at high temperatures and converts into hydrogen and carbon monoxide. This paper provides a feasibility study for the gasification of CBS in an atmospheric entrained flow reactor for syngas production. Experiments have shown that CBS can be successfully processed and gasified in the entrained flow reactor to produce syngas with almost no tar content and low residual carbon formation. High reactor temperature and steam/carbon ratio is favourable for H-2 production. At 1400 degrees C with steam/carbon ratio of 5, the syngas components are similar with that in equilibrium. A synergistic effect exists between coal and bio-oil in coal/bio-oil slurry gasification which might be caused by the catalysis effect of alkali metals and alkaline earth metals in bio-oil. (C) 2016 Elsevier Ltd. All rights reserved.</p
Neural network aided approximation and parameter inference of non-Markovian models of gene expression
10.1038/s41467-021-22919-1Nature Communications121261
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