Summary Objective We sought to determine (1) whether change in the tibial plateau inclination (TPI) after high tibial osteotomy (HTO) is different from change in the knee joint line orientation ...(KJLO) relative to the ground; (2) whether, in varus knee OA patients before and after HTO, these radiographic measures are different from those in normal control; and (3) whether the postoperative values of the TPI and KJLO relative to the ground are associated with short term clinical outcome scores after HTO. Design Fifty patients who underwent HTO and 75 normal controls were assessed with four radiographic measures. We compared the measures before HTO with those after HTO and with those of the normal controls, then examined associations between the postoperative radiographic measures and clinical outcome scores 1-year after HTO. Results After HTO, TPI increased 9.0°, whereas KJLO relative to the ground only increased 4.1°, with a compensatory change of the ankle joint line orientation. However, the postoperative KJLO relative to the ground in the HTO group was significantly different from that of the normal controls (mean difference, 4.9°; P < 0.001). In the multiple regression analyses, the postoperative radiographic measures were not associated with outcome clinical scores 1 year after HTO. Conclusion After HTO the relative KJLO changed significantly less than did the anatomical geometry of the proximal tibia. Although the KJLO after the HTO was still significantly different from that of normal knees, its value did not adversely affect clinical outcome scores 1 year after HTO.
A Case Study on the Origin of Near‐Earth Plasma Glocer, A.; Welling, D.; Chappell, C. R. ...
Journal of geophysical research. Space physics,
November 2020, Letnik:
125, Številka:
11
Journal Article
Recenzirano
Odprti dostop
This study presents simulations of the coupled space environment during a geomagnetic storm that separates the different sources of near‐Earth plasma. These simulations include separate fluids for ...solar wind and ionospheric protons, ionospheric oxygen, and the plasmasphere. Additionally, they include the effects of both a hot ring current population and a cold plasmaspheric population simultaneously for a geomagnetic storm. The modeled ring current population represents the solution of bounce‐averaged kinetic solution; the core plasmaspheric model assumes a fixed temperature of 1 eV and constant pressure along the field line. We find that during the storm, ionospheric protons can be a major contributor to the plasmasheet and ring current and that ionospheric plasma can largely displace solar wind protons in much of the magnetosphere under certain conditions. Indeed, the ionospheric source of plasma cannot be ignored. Significant hemispheric asymmetry is found between the outflow calculated in the summer and winter hemispheres, consistent with past observations. That asymmetric outflow is found to lead to asymmetric filling of the lobes, with the northern (summer) lobe receiving more outflow that has a higher proportion of O+ and the southern (winter) lobe receiving less outflow with a higher proportion of H+. We moreover find that the inclusion of the plasmasphere can have a system‐wide impact. Specifically, when the plasmasphere drainage plume reaches the magnetopause, it can reduce the reconnection rate, suppress ionospheric outflow and change its composition, change the composition in the magnetosphere, and reduce the ring current intensity.
Key Points
Ionospheric H+ is a critically important contributor to the magnetosphere during a storm
Seasonal effect on outflow create asymmetric filling of the lobes
The inclusion of an additional plasmaspheric fluid has system‐wide effects
A memory cell consisting of a Pt/VO2/Pt switch element and a Pt/NiO/Pt memory element connected in series. By applying a voltage higher than Vth of 0.6 V, the switch element reaches the on state and ...the cell can be accessed. Since reset and set voltages are higher than Vth, information can be written by simply applying an appropriate voltage to a selected cell. By applying a voltage lower than Vth to the other cells, we can keep the other cells in the off state and prevent interference between the selected cell and the others.
Relativistic electrons in the outer radiation belt are highly dynamic and respond to interplanetary solar wind structures interacting with the Earth's magnetic field. A known mechanism dictating ...electron dynamics is the drift-resonant interaction with ultralow frequency (ULF) waves. The present work simulates the ring current and radiation belt electron populations in the bounce-averaged, kinetic Comprehensive Inner Magnetosphere-Ionosphere model coupled with the Block Adaptive Tree Solar Wind Roe-type Upwind Scheme global magnetospheric magnetohydrodynamic (MHD) code using an idealized ULF wave solar wind density driver. ULF waves generated with 10 min periods (at 1.67 mHz frequencies) in the MHD model are characterized and the corresponding energization of electrons and radial transport of electron phase space density is presented. The drift-resonant electron energy is determined in the simulation and is consistent with the electron resonance conditions in dipolar magnetic fields. The present results will be an important component of understanding inner magnetospheric dynamics and how these inner magnetospheric populations interact with ULF waves resulting from interplanetary solar wind structures.
Objectives: Histone deacetylase (HDAC) is an important therapeutic target in cancer. Two of the main anticancer mechanisms of HDAC inhibitors are induction of terminal differentiation and inhibition ...of cell proliferation. To investigate the role of HDAC in maintenance of self‐renewal and cell proliferation, we treated mesenchymal stem cells (MSCs) that originated from adipose tissue or umbilical cord blood with valproic acid (VPA) and sodium butyrate (NaBu).
Materials and methods: Human MSCs were isolated from mammary fat tissue and cord blood. We performed MTT assay and flow cytometry‐based cell cycle analysis to assess self‐renewal of MSCs. In vitro differentiation assays into osteogenic, adipogenic, neurogenic and chondrogenic lineages were conducted to investigate MSC multipotency. Immunocytochemistry, Western blot and reverse transcription‐polymerase chain reaction were used to interrogate molecular pathways.
Results: VPA and NaBu flattened the morphology of MSCs and inhibited their growth. VPA and NaBu activated the transcription of p21CIP1/WAF1 by increasing the acetylation of histone H3 and H4 and eventually blocked the cell cycle at G2/M phase. The expression level of p16INK4A, a cdk inhibitor that is closely related to cellular senescence, was not changed by HDAC inhibitor treatment. We performed controlled differentiation into bone, fat, cartilage and nervous tissue to elucidate the role of HDAC in the pluripotency of MSC to differentiate into functional tissues. VPA and NaBu decreased the efficiency of adipogenic, chondrogenic, and neurogenic differentiation as visualized by specific staining and reverse transcription‐polymerase chain reaction. In contrast, osteogenic differentiation was elevated by HDAC inhibitor treatment.
Conclusion: HDAC activity is essential for maintaining the self‐renewal and pluripotency of MSCs.
Topological semimetals host electronic structures with several band-contact points or lines and are generally expected to exhibit strong topological responses. Up to now, most work has been limited ...to non-magnetic materials and the interplay between topology and magnetism in this class of quantum materials has been largely unexplored. Here we utilize theoretical calculations, magnetotransport and angle-resolved photoemission spectroscopy to propose Fe
GeTe
, a van der Waals material, as a candidate ferromagnetic (FM) nodal line semimetal. We find that the spin degree of freedom is fully quenched by the large FM polarization, but the line degeneracy is protected by crystalline symmetries that connect two orbitals in adjacent layers. This orbital-driven nodal line is tunable by spin orientation due to spin-orbit coupling and produces a large Berry curvature, which leads to a large anomalous Hall current, angle and factor. These results demonstrate that FM topological semimetals hold significant potential for spin- and orbital-dependent electronic functionalities.
SARS-CoV-2 can spread by close contact through large droplet spray and indirect contact via contaminated objects. There is mounting evidence that it can also be transmitted by inhalation of infected ...saliva aerosol particles. These particles are generated when breathing, talking, laughing, coughing or sneezing. It can be assumed that aerosol particle concentrations should be kept low in order to minimize the potential risk of airborne virus transmission. This paper presents measurements of aerosol particle concentrations in a gym, where saliva aerosol production is pronounced. 35 test persons performed physical exercise and aerosol particle concentrations, CO2 concentrations, air temperature and relative humidity were obtained in the room of 886 m³. A separate test was used to discriminate between human endogenous and exogenous aerosol particles. Aerosol particle removal by mechanical ventilation and mobile air cleaning units was measured. The gym test showed that ventilation with air-change rate ACH = 2.2 h−1, i.e. 4.5 times the minimum of the Dutch Building Code, was insufficient to stop the significant aerosol concentration rise over 30 min. Air cleaning alone with ACH = 1.39 h−1 had a similar effect as ventilation alone. Simplified mathematical models were engaged to provide further insight into ventilation, air cleaning and deposition. It was shown that combining the above-mentioned ventilation and air cleaning can reduce aerosol particle concentrations with 80 to 90% , depending on aerosol size. This combination of existing ventilation supplemented with air cleaning is energy efficient and can also be applied for other indoor environments.
•Aerosol particle concentration measurements in a gym with 35 exercising persons.•Assessment of deposition, ventilation and air cleaning (AC) for aerosol reduction.•Gym ventilation with ACH = 2.2 h−1 has similar effect as air cleaning with ACH = 1.39 h−1.•Application of simplified mathematical models to predict other scenarios.•Combining ventilation & AC gives reduction factors 2.3 up to 3.7 depending on aerosol size.
Background
Microbial colonization of the airway plays a role in the pathogenesis of asthma; however, the effect of the upper airway microbiome on childhood asthma is not fully understood. We analyzed ...the metagenome of airway microbiome to understand the associated role of upper airway microbiome with the natural course of childhood asthma.
Methods
Nasopharyngeal swabs were collected from children with asthma, those in asthma remission, and control groups. High‐throughput sequencing was used to examine the structure and functional dynamics of the airway microbiome with respect to asthma phenotypes.
Results
The composition of microbiota differed among healthy control, asthma, and remission groups. The relative abundance of Streptococcus was negatively associated with FEV1% predicted (P = .023) and that of Staphylococcus was negatively associated with methacholine PC20 (P = .013). Genes related to arachidonic acid metabolites, lysine residues, and glycosaminoglycans in the microbiome could be associated with airway inflammation. In particular, genes related to synthesis of anti‐inflammatory prostaglandin E2 (PGE2) were not detected from the airway microbiome in the asthma group.
Conclusions
These data suggest that alterations in the composition and function of the upper airway microbiome could be related with the natural course of asthma in children.
Aim
This study aimed to investigate the association between Twitter exposure and the number of citations for coloproctology articles.
Method
Original articles from journals using Twitter between June ...2015 and May 2016 were evaluated for the following characteristics: publishing journal; article subject; study design; nationality, speciality and affiliation of the author(s); and reference on Twitter. Citation data for these articles were retrieved from Google Scholar (https://scholar.google.com) in January 2018. We performed a univariate analysis using these data followed by a multivariate, logistic regression analysis to search for factors associated with a high citation level, which was defined as accrual of more than five citations.
Results
Out of six coloproctology journals listed on the InCites JCR database, three (Diseases of the Colon & Rectum, Colorectal Disease and Techniques in Coloproctology) used Twitter, where 200 (49.5%) out of a total of 404 articles had been featured. Citation rates of articles that featured on Twitter were significantly higher than those that did not (11.4 ± 9.2 vs 4.1 ± 3.1, P < 0.001). In multivariate analysis, Twitter exposure (OR 8.6, P = 0.001), European Union nationality (OR 2.4, P = 0.004), Colorectal Disease journal (OR 3.3, P = 0.005) and systematic review articles (OR 3.4, P = 0.009) were associated with higher citation levels.
Conclusion
Article exposure on Twitter was strongly associated with a high citation level. Medical communities should encourage journals as well as physicians to actively utilize social media to expedite the spread of new ideas and ultimately benefit medical society as a whole.
A Comprehensive Inner Magnetosphere‐Ionosphere (CIMI) model was developed to study the dynamic variations of the radiation belts, ring current, and plasmasphere as well as the couplings between these ...populations and with the ionosphere. The CIMI model has been used in multiple studies to simulate a number of magnetic storms and reproduce many observable features that involve cross‐region and cross‐energy processes. This model has been continuously validated and improved. In this study, we report on two major recent advancements in CIMI. The first improvement is transforming coordinates in both configuration and velocity space into uniform grids. Numerical schemes, especially those of high order, are generally more stable on such uniform grids. The second advancement is to solve both advection and diffusion in the CIMI equation in a single coordinate system. Previously, the phase space distribution was expressed in terms of the first two adiabatic invariants when solving for particle drift, whereas particle distributions were transformed into energy and pitch angle for calculating wave diffusion. In the new approach in CIMI, particles and distribution functions are identified by their momentum. This change avoids interpolation errors inherent in the mapping of the phase space distribution when switching back and forth between advective and diffusive transport. We describe the detailed implementation of these recent advancements in the CIMI model, and demonstrate how the newly improved model provides better predictions of the ring current and radiation belt dynamics.
Key Points
In the new CIMI model, all coordinates are in uniform grids. High‐order scheme is applied to solve the advection of fast‐drifting particles
In the new CIMI model, a single coordinate system is used to solve the particle transport in both configuration and velocity space
The new CIMI model provides more accurate predictions of the radiation belts, the ring current, and the plasmasphere