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2021 ◽  
Vol 18 (4) ◽  
pp. 769-777
Author(s):  
A. N. Kulikov ◽  
E. V. Danilenko ◽  
A. R. Kuznetsov

The “gold standard” of modern vitreoretinal surgery is silicone oil tamponade of the vitreous cavity. The lens opacity development is in the list of complications of prolonged silicone oil eye filling (from 2 weeks to 2 years). Polydimethylsiloxanes hydrophobicity, direct contact with the front of the silicone bladder, macrophage and toxic reaction, trophic disturbances are the causes leading to the cataract initiation. This makes the problem of cataract surgery and preliminary intraocular lens calculation in silicone oil filled eyes before its removing very relevant as well as cloudy retina visualization and the necessity of minimization of number of operations through their combination. Certainly, the main error in IOL power calculation is associated with axial length measurement inaccuracy, as the most significant term of an equation. Silicone oil filled eyes biometry errors, and, consequently, postoperative refraction biases remain unresolved problem until now. To date authors report only 58 % of cases in which target refraction was achieved after combined surgery. Some researchers figure out that average calculation error after phacoemulsification with IOL implantation in avitreal eyes was 0.8 D despite of the optical biometry usage. Today it is represented by several methods: partial coherent interferometry, optical low-coherence reflectometry and optical coherence tomography, which are implemented in devices such as IOLMaster 500, Lenstar LS 900 and IOLMaster 700, which have their own characteristics and measurement accuracy. Their advantages as well as creation an accurate IOL calculation method for silicone oil filled eyes could reduce postoperative refraction error that outline significant medical and social problem.


2021 ◽  
pp. 1-10
Author(s):  
Lei Zhang ◽  
Yiye Shao ◽  
Chunlei Tang ◽  
Zhen Liu ◽  
Dingzhong Tang ◽  
...  

<b><i>Background:</i></b> Parkinson’s disease (PD) is a common neurodegenerative disease affecting the elderly, but there is no blood test for PD diagnosis in the clinic currently. This study aimed to explore promising biomarkers in platelets (PLTs) for PD diagnosis. <b><i>Methods:</i></b> PLTs were isolated from whole blood samples of PD patients and healthy controls (HCs), and RNA was extracted for sequencing. RNA-seq was performed on the Illumina HiSeq platform. <b><i>Results:</i></b> A total of 2,221 genes with differential transcript levels (GDTLs) were identified between PD patients and HCs, 1,041 of which are upregulated genes and 1,180 of which are downregulated genes. <i>WASH5P</i> was the most upregulated gene and <i>AC114491.1</i> was the most downregulated gene. Among the top 12 most relevant genes, metastasis-associated lung adenocarcinoma transcript 1 (<i>MALAT1</i>), eukaryotic elongation factor 1A (<i>EEF1A1</i>), and cathepsin S (<i>CTSS</i>) were reported to be associated with PD. Furthermore, gene ontology analysis showed that the most significant term in biological processes was neutrophil degranulation; the most enriched term in cellular components was cytoplasmic vesicle lumen; and tumor necrosis factor receptor superfamily binding was the most significant term in molecular functions. In the Kyoto Encyclopedia of Genes and Genomes enrichment analysis, inflammation-related pathway accounts for the majority. <b><i>Conclusion:</i></b> Our findings demonstrated <i>WASH5P</i>, <i>MALAT1</i>, <i>EEF1A1,</i> and <i>CTSS</i> may be promising biomarkers in PD, which may contribute to improving the effectiveness and accuracy of diagnosis for PD in the future.


Author(s):  
Isha Singh ◽  
Priyanka Parte

Testis-specific histone variants are crucial to promote open chromatin structure to enable nucleosome disassembly in the final stages of spermiogenesis. However, even after histone replacement, mature sperm retain a proportion of these variants, the function of which is unknown. The present study aimed to understand the functional relevance of the retained H2B and H2A variants, TH2B and TH2A. While no literature is available on the phenotype of TH2A knockouts, TH2B/TH2A double knockout male mice are reported to be infertile. In this study, ChIP-seq analysis was done for TH2B and TH2A to understand the epigenomics of the retained TH2B and TH2A, using murine caudal sperm. Distribution across genomic partitions revealed ∼35% of the TH2B peaks within ±5 kb of TSS whereas TH2A peaks distribution was sparse at TSS. Gene Ontology revealed embryo development as the most significant term associated with TH2B. Also, based on genomic regions, TH2B was observed to be associated with spindle assembly and various meiosis-specific genes, which is an important finding as TH2A/TH2B DKO mice have been reported to have defective cohesin release. A comparison of mouse and human TH2B-linked chromatin revealed 26% overlap between murine and human TH2B-associated genes. This overlap included genes crucial for embryogenesis. Most importantly, heterogeneity in the epigenetic landscape of TH2A and TH2B was seen, which is intriguing as TH2B and TH2A are well reported to be present in the same nucleosomes to promote open chromatin. Additionally, unlike TH2B, TH2A was enriched on the mitochondrial chromosome. TH2A was found to be associated with Nuclear insertion of Mitochondrial DNA sequences (NUMTs) in sperm. A comprehensive analysis of these observations indicates novel functions for the sperm-retained TH2B and TH2A.


2021 ◽  
Vol 15 ◽  
Author(s):  
Yang Zhang ◽  
Min Ma ◽  
Zhonghua Xie ◽  
Heng Wu ◽  
Nan Zhang ◽  
...  

Disruptions in brain connectivity have been widely reported in Alzheimer’s disease (AD). Morphometric similarity (MS) mapping provides a new way of estimating structural connectivity by interregional correlation of T1WI- and DTI-derived parameters within individual brains. Here, we aimed to identify AD-related MS changing patterns and genes related to the changes and further explored the molecular and cellular mechanism underlying MS changes in AD. Both 3D-T1WI and DTI data of 106 AD patients and 106 well-matched healthy elderly individuals from the ADNI database were included in our study. Cortical regions with significantly decreased MS were found in the temporal and parietal cortex, increased MS was found in the frontal cortex and variant changes were found in the occipital cortex in AD patients. Mean MS in regions with significantly changed MS was positively or negatively associated with memory function. Negative MS-related genes were significantly downregulated in AD, specifically enriched in neurons, and participated in biological processes, with the most significant term being synaptic transmission. This study revealed AD-related cortical MS changes associated with memory function. Linking gene expression to cortical MS changes may provide a possible molecular and cellular substrate for MS abnormality and cognitive decline in AD.


Sensors ◽  
2021 ◽  
Vol 21 (16) ◽  
pp. 5350
Author(s):  
Carlos Crespo-Cadenas ◽  
María José Madero-Ayora ◽  
Juan A. Becerra

This work presents a strategy to upgrade models for power amplifier (PA) behavioral modeling and digital predistortion (DPD). These incomplete structures are the consequence of nonlinear order and memory depth model truncation with the purpose of reducing the demand of the limited computational resources available in standard processors. On the other hand, the alternative use of model structures pruned a priori does not guarantee that every significant term is included. To improve the limited performance of an incomplete model, a general procedure to augment its structure by incorporating significant terms is demonstrated. The sparse nature of the problem allows a successive search incorporating additional terms with higher nonlinear order and memory depth. This approach is investigated in the modeling and linearization of a commercial class AB PA operating at a compression point of about 6 dB, and a class J PA operating near saturation. Results highlight the capabilities of this upgrading procedure in the improvement of linearization capabilities of DPDs.


2021 ◽  
Vol 6 (2) ◽  
pp. 137
Author(s):  
Ayu Wulandari ◽  
Relsas Yogica ◽  
Ganda Hijrah Selaras ◽  
Ristiono Ristiono

This research is an experimental research which aims to see the influence of Teams Game Tournament (TGT) learning model on the motivation of students on immune system material at SMA Pembangunan Laboratorium UNP academic year 2018/2019. The implementation of this study does not allow researchers to control variables as a whole so that this study belongs to the quasi-experimental category with the design of control group posttest only design. Sampling in this study used saturation sampling technique. The technique of data analysis used statistical tests, namely the t test. The results of statistical tests showed that in a significant term (α = 0.05) the value of tcount> t tableis obtained, which is 3.28 > 1.67, then H0 is rejected and H1 is accepted. It can be concluded that the motivation of students using the Teams Game Tournament (TGT) learning model is higher than the motivation of students who use conventional learning. It can be interpreted that there is an influence of the Teams Game Tournament (TGT) learning model on the motivation of students on immune system material at SMA Pembangunan Laboratorium UNP.


Author(s):  
Irina I. Rypina ◽  
Timothy R. Getscher ◽  
Lawrence J. Pratt ◽  
Baptiste Mourre

AbstractThis paper presents analyses of drifters with drogues at different depths – 1, 10, 30, 50 m – that were deployed in the Mediterranean Sea to investigate frontal subduction and upwelling. Drifter trajectories were used to estimate divergence, vorticity, vertical velocity, and finite-size Lyapunov exponents (FTLEs), and to investigate the balance of terms in the vorticity equation. The divergence and vorticity are O(f) and change sign along trajectories. Vertical velocity is O(1 mm/s), increases with depth, indicates predominant upwelling with isolated downwelling events, and sometimes changes sign between 1 and 50 m. Vortex stretching is one of, but not the only, significant term in the vorticity balance. 2D FTLEs are 2 × 10−51/s after 1 day, twice larger than in a 400-m-resolution numerical model. 3D FTLEs are 50% larger than 2D FTLEs and are dominated by the vertical shear of horizontal velocity. Bootstrapping suggests uncertainty levels of ~10% of the time-mean absolute values for divergence and vorticity. Analysis of simulated drifters in a model suggests that drifter-based estimates of divergence and vorticity are close to the Eulerian model estimates, except when drifters get aligned into long filaments. Drifter-based vertical velocity is close to the Eulerian model estimates at 1 m but differs at deeper depths. The errors in the vertical velocity are largely due to the lateral separation between drifters at different depths, and partially due to only measuring at 4 depths. Overall, this paper demonstrates how drifters, heretofore restricted to 2D near-surface observations, can be used to learn about 3D flow properties throughout the upper layer of the water column.


2021 ◽  
Author(s):  
Yang Zhang ◽  
Min Ma ◽  
Zhonghua Xie ◽  
Heng Wu ◽  
Nan Zhang ◽  
...  

Abstract Disruptions of brain connectivity have been widely reported in Alzheimer's disease (AD). Morphometric similarity (MS) mapping provides a new way of estimating structural connectivity by inter-regional correlation of T1WI and DTI derived parameters within individual brains. Here, we aimed to identify AD-related MS changing patterns and genes related to the changes and further explore the molecular and cellular mechanism underlying MS changes in AD. Both 3D-T1WI and DTI data of 106 AD patients and well-matched 106 healthy elders from the ADNI database were included in our study. Cortical regions with significantly decreased MS were found in the temporal and parietal cortex, increased MS in the frontal cortex and variant changes in the occipital cortex in AD patients. Mean MS in regions with significantly changed MS was positively or negatively associated with memory function. The negative MS-related genes were significantly down-regulated in AD, specifically enriched in neurons, and participated in biological process with the most significant term in synaptic transmission. This study revealed AD-related cortical MS changes associated with memory function. Linking gene expression to cortical MS changes may provide a possible molecular and cellular substrate for MS abnormality and cognition decline in AD.


2021 ◽  
Author(s):  
Irina I. Rypina ◽  
Timothy R. Getscher ◽  
Larry J. Pratt ◽  
Baptiste Mourre

&lt;p&gt;We present analyses of drifters with drogues at 1, 10, 30 and 50 m, which were deployed in the Mediterranean Sea to investigate subduction and upwelling processes. Drifter trajectories were used to estimate divergence, vorticity, vertical velocity, and finite-size Lyapunov exponents (FTLEs), and to investigate the magnitudes of terms in the vertical vorticity equation. The divergence and vorticity are O(f) and change sign along trajectories. Vertical velocity is O(1 mm/s), is larger at depth, indicates predominant upwelling with isolated downwelling events, and sometimes changes sign between 1 and 50 m. Vortex stretching is one of, but not the only, significant term in the vertical vorticity balance. 2D FTLEs are 2x10^(-5) 1/s after 1 day, about twice larger than in a 400-m-resolution numerical model. 3D FTLEs are 50% larger than 2D FTLEs and are dominated by the vertical shear of horizontal velocity. Bootstrapping-based uncertainty for both divergence and vorticity is ~10% of the time-mean absolute values. Simulated drifters in a model suggest that drifter-based divergence and vorticity are close to true model values, except when drifters get aligned into long and narrow filaments. Drifter-based vertical velocity is close to true values in the model at 1 m but differs from the true model values at deeper depths. The errors in the vertical velocity are largely due to the lateral separation between drifters at different depths, and partially due to having drifters at only 4 depths. Overall, multi-level drifters provided useful information about the 3D flow structure.&lt;/p&gt;


2020 ◽  
Vol 77 (11) ◽  
pp. 3971-3975 ◽  
Author(s):  
A. M. Makarieva ◽  
A. V. Nefiodov ◽  
D. Sheil ◽  
A. D. Nobre ◽  
A. V. Chikunov ◽  
...  

AbstractIn a recent paper Rousseau-Rizzi and Emanuel (2019) presented a derivation of an upper limit on maximum hurricane velocity at the ocean surface. This derivation was based on a consideration of an infinitely narrow (differential) Carnot cycle with the warmer isotherm at the point of the maximum wind velocity. Here we show that this derivation neglected a significant term describing the kinetic energy change in the outflow. Additionally, we highlight the importance of a proper accounting for the power needed to lift liquid water. Finally, we provide a revision to the formula for surface fluxes of heat and momentum showing that, if we accept the assumptions adopted by Rousseau-Rizzi and Emanuel (2019), the resulting velocity estimate does not depend on the flux of sensible heat.


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