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In somatic tissue differentiation, chromatin accessibility changes govern priming and precursor commitment towards cellular fates1–3. Therefore, somatic mutations are likely to alter chromatin accessibility patterns, as they disrupt differentiation topologies leading to abnormal clonal outgrowth. However, defining the impact of somatic mutations on the epigenome in human samples is challenging due to admixed mutated and wild-type cells. Here, to chart how somatic mutations disrupt epigenetic landscapes in human clonal outgrowths, we developed genotyping of targeted loci with single-cell chromatin accessibility (GoT–ChA). This high-throughput platform links genotypes to chromatin accessibility at single-cell resolution across thousands of cells within a single assay. We applied GoT–ChA to CD34+ cells from patients with myeloproliferative neoplasms with JAK2V617F-mutated haematopoiesis. Differential accessibility analysis between wild-type and JAK2V617F-mutant progenitors revealed both cell-intrinsic and cell-state-specific shifts within mutant haematopoietic precursors, including cell-intrinsic pro-inflammatory signatures in haematopoietic stem cells, and a distinct profibrotic inflammatory chromatin landscape in megakaryocytic progenitors. Integration of mitochondrial genome profiling and cell-surface protein expression measurement allowed expansion of genotyping onto DOGMA-seq through imputation, enabling single-cell capture of genotypes, chromatin accessibility, RNA expression and cell-surface protein expression. Collectively, we show that the JAK2V617F mutation leads to epigenetic rewiring in a cell-intrinsic and cell type-specific manner, influencing inflammation states and differentiation trajectories. We envision that GoT–ChA will empower broad future investigations of the critical link between somatic mutations and epigenetic alterations across clonal populations in malignant and non-malignant contexts.The JAK2V617F mutation leads to epigenetic rewiring in a cell-intrinsic and cell-type-specific manner, influencing inflammation states and differentiation trajectories in patients with myeloproliferative neoplasms. [ABSTRACT FROM AUTHOR]

The magnetometer is an essential component in a number of scientific and technical disciplines, including instrumentation and space navigation. To detect magnetic fields, a traditional Lorentz force capacitive magnetometer utilizes transverse, parallel-plate combs. Due to the substantial squeeze-film damping effects, increasing the number of comb fingers reduces the quality factor, and hence does not increase the device's sensitivity, thus restricting applications. To address this shortcoming, we propose a longitudinal comb transducer design for space navigation. Its structure consists of a proof mass and beams, acting as driving elements, and two pairs of longitudinal combs, acting as electrostatic sensing elements. The magnetic field is measured by using the displacement that the Lorentz force induces on the current-carrying beams. Differential capacitance is utilized to transduce the displacement into the electrical domain. The resulting MEMS magnetometer has been fabricated using a low-cost MEMS process. A test bed was set under near-vacuum conditions to measure the static capacitance and resonant frequency of the sensing element. The static capacitance was found to be 1.27 pF, while measurements at the resonance frequency of 35.4 kHz show a high quality factor of 200 and consequently a high sensitivity. The resolution is estimated to be 295 n T / Hz . With the exception of slight differences, these results were in accordance with the simulation. [ABSTRACT FROM AUTHOR]

In this study, we report the deposition of thin layers of erbium-doped silica onto silicon substrates using the sol–gel method. Deposition was performed by spin coating, followed by drying and heat treatment in the range of 500°C up to 900°C. Different acid catalysts with various erbium doping concentrations were investigated to assess their impact on the film properties including thickness and refractive index. Under the same experimental conditions, the acid catalyst used significantly influenced the thickness and shrinkage of the films, irrespective of the erbium doping concentration. The key factors for this behavior are the viscosity of the sols and the gelation time, which vary tremendously depending on the acid used and the doping concentration. Strong acids were found to produce films with the highest resistance to shrinkage during annealing compared to weak acids. From the elliposometric investigation, the interplay among the doping concentration, pore formation, and annealing was found to affect the refractive index of the synthesized film. [ABSTRACT FROM AUTHOR]

The main challenge that hinders lithium-ion batteries in space applications is their poor performance at subzero temperatures. Such poor performance is primarily due to the low ionic conductivity and freezing of the electrolyte, leading to the loss of battery capacity. This research investigates the behavior of lithium-ion batteries at low temperatures by employing electrochemical and material characterization techniques. Based on the electrochemical behavior of the battery cells, lithium-ion batteries' performance declined rapidly at − 30 °C. The major findings indicate that charging at low-temperature conditions increases the impedance, which slows down the reaction kinetics affecting the intercalation of lithium ions. According to the results obtained from the ex situ material characterization analysis, the main factor that induces this behavior is the freezing and the decomposition of the electrolyte at the cathode-electrolyte interphase and the mechanical degradation of the active materials of the cathode. These changes lead to interfacial instability and considerable development of resistance to the flow of charges. The findings in this study contribute to the development of lithium-ion batteries for low temperature and space applications by understanding the behavior of lithium-ion batteries in subzero temperature environments. [ABSTRACT FROM AUTHOR]

Design and fabrication of an effective, affordable, and lightweight material to solve the electromagnetic interference (EMI) problem, through improving the microwave absorption, have become an urgent need during the present period of fast growth of electronic devices and wireless telecommunication technology. Manganese ferrite MnFe2O4 nanoparticles (MFO NPs) with three different particle sizes were synthesized using the hydrothermal reaction technique. The MFO NPs were then mixed with carbon nanotubes (CNTs) to fabricate a new EMI shielding mat, through a free polymer-binder surface-engineered tape-casting (SETC) method. The fabricated CNTs-MFO mats have demonstrated superior EMI shielding in the X-band. CNT-only mat (with 48 µm thickness) had a total effective shielding (SEAll), absorption shielding (SEA), and reflection shielding (SER) of 36 dB, 23 dB, and 10 dB, respectively. SEAll of 36 dB proves that the CNT-only mat is a promising material for microwave absorbing materials. However, 1 wt.% of CNTs-MFO-1 has enhanced the SEAll by 14.5% at a frequency of 10.51 GHz. This improvement in SEAll is because of the MFO's magnetic properties and the heterogeneous structure created by the MFO within the CNT mat, which enhances the EM wave's absorption. [ABSTRACT FROM AUTHOR]

The dielectric properties of polymer nanocomposites (PNCs) are crucial in designing electronic packaging, energy storage capacitors, electromagnetic shielding, and biomedical sensors and actuators. The conventional mixing rules-based methods such as the Kerner model, Maxwell–Garnett (MG) model, Maxwell–Wagner-Sillars (MWS) model, Bruggeman model solely rely on the volume fraction (vol%), which is often inadequate to predict the frequency dependency of the effective permittivity of the PNCs, they also do not account for the sizes of the inclusions. A computational model was developed to estimate the dielectric permittivity and the dielectric loss of PNCs using COMSOL multi-physics. Experimental data from previously published references confirmed the validity of the finite element analysis (FEA) based model. Next, the COMSOL model was utilized to quantitatively analyze the complex dielectric constant as a function of the applied frequency, the dielectric properties of the inclusion and the polymer matrix, and the volume fraction of the inclusion. The study was conducted with a polymer matrix of polymethylmethacrylate (PMMA) and five nanoparticles including semiconductor material silicon (Si), inorganic zinc-sulfide (ZnS), metal gold (Au), metal-oxide titanium oxide (TiO2), and dielectric fillers BaTiO3 (BT). The results show that the frequency-dependent dielectric relaxation behavior, the MWS interfacial polarization, significantly influences the dielectric properties. A 10 vol% inclusion of Si, ZnS, and BT resulted in MWS frequency of 103, 1584, 105 Hz. The charge barrier is most substantial in low frequency as it restricts electric field propagation around the inclusion. However, at a significantly high frequency, the charge barrier breaks, lowering the dielectric constant of the composite. In addition to that, a unique behavior was observed in high conductive fillers PNCs (e.g., Au) as the permittivity showed a fillers size dependence even with the same volume fraction. At frequency nearing 105 Hz, the Au-PMMA composite showed a higher permittivity with smaller nanoparticles inclusion. This is a significant finding contrary to the existing understandings based on the conventional mixing rules (e.g., MWS, MG, Bruggeman, Kerner model), which does not account for the size of inclusions. The present study has important implications for device engineers and materials manufacturers to choose appropriate materials with desired properties for optoelectronic packaging applications. [ABSTRACT FROM AUTHOR]

Northeast Asia has been suffering from dramatic increases of particulate matter (PM) since the late 1990s, and it still continues to undergo haze despite various abating regulations. In this study, we investigated aerosol-cloud-precipitation (ACP) interactions with the varied PM, and the impact of long-range transport (LRT) process on ACP in springtime was assessed in Northeast Asia. Our long-term (1995–2019) analysis of PM10 exhibited the correlation with decreases of both sunshine duration and drizzle occurrences that can be interpreted as direct and indirect aerosol effects, while cloud cover induced by the varied PM10 was found only in more than 90% cloud cover (9/10–10/10 category). The online WRF-Chem with wind-blown dust simulation indicated that cloud water was affected by secondary inorganic aerosol (SIA) formation near the surface in upwind areas dominantly, whereas, along the LRT pathway, cloud water perturbation altitudes were increased quasi-linearly toward downward between 1 and 3 km. The gas-to-particle conversion ratios of sulfur ([SO42−]/[SO2 + SO42−]) and nitrogen ([NO3−]/[NO2 + NO3−]) both remain aloft long at the same vertical levels of most perturbed cloud altitude enough to be transported over long distance in springtime. Formations of sulfate and nitrate showed different ACP interaction timing; distinctive shifts in the ratios observed at the exit (Shanghai-Yellow Sea) by nitrate, and entrance areas (Seoul-Tokyo) by sulfate along the LRT pathway, respectively, with higher ratios of 0.8 or more in springtime. Our results indicate that ACP processes have been enhanced at a LRT-related altitude with different SIA production timings that can be considered in species-specific springtime PM abatements over Northeast Asia. [ABSTRACT FROM AUTHOR]

Tape-casting method has been employed to prepare poly(vinylidene fluoride-co-hexafluoropropylene) (PVDF–HFP)-based porous membranes with different microstructures. The prepared porous membranes are characterized by scanning electron microscopy, differential scanning calorimetry and tensile strength to analyse their morphological, thermal and mechanical properties. Polymer membrane with equal amount of urea and PVDF–HFP weight ratio is found as best membrane due to its high porosity, high liquid uptake, excellent thermal and mechanical properties. Owing to above-mentioned properties, the highest porous film (PM66) shows improved electrochemical properties with flexible carbon nanotube-based composite electrode, which makes it a potential candidate as a separator for the flexible Li-ion batteries. The discharge capacity of flexible lithium titanate electrode with PM66 was found to be ~142 mAh g–1 at 0.1 C rate and was stable up to 100 cycles. [ABSTRACT FROM AUTHOR]

This paper presents the design of a novel multi-ring vibratory gyroscope. The design incorporates two sets of rings, inner and outer, separated by a set of perforated inertial masses and connected to the outermost anchors by the means of springs. The structure's performance is enhanced by utilizing springs with bends that play a significant role in reducing the device's sensitivity to external shocks. The amalgamation of multiple rings with the C-shaped springs provides higher sensitivity with high shock resistance that makes this multi-vibrating ring gyroscope an ideal inertial sensor for space applications. Such a structure yields in-plane flexural modes that are utilized to sense rotation along the axis normal to the structure's plane. [ABSTRACT FROM AUTHOR]

Lithium iron phosphate (LiFePO4) micro-particles were synthesized using hydrothermal method with two different Fe precursors (FeSO4 and FeCl2). Freestanding and flexible LiFePO4/multi-walled carbon nanotube (MWCNT) composite electrodes were prepared using surface-engineered tape-casting method. FeSO4 precursor-based composite electrode exhibited improved electrical and electrochemical performances compared with the FeCl2 precursor-based composite electrode. A maximum electrical conductivity of 1.54 × 103 Scm−1 has been obtained for FeSO4 precursor-based LiFePO4 micro-particles at 75 °C. LiFePO4/MWCNT composite electrode exhibited better capacity (~ 126 mAhg−1 at 0.1 C rate) and electrochemical reversibility in line with the results on the literature. Moreover, after 100 cycles at the rate of 1 C, specific capacity of around 105 mAhg−1 and retention rate of ~ 99% were achieved. The improved performance of LiFePO4/MWCNT composite electrode after 100 cycles leads to analyze extensive electrochemical properties and ex situ studies. [ABSTRACT FROM AUTHOR]

In this paper, we report the effect of geometric parameters by calculating the capacitance scale factor of micromachined vibrating wheel on gimbal gyroscope with various shapes and mass conditions. The behavior of capacitance for vibratory torsional gyroscope with various shapes and mass conditions is investigated using MEMS+™. The structure dimensions of the gyroscope are optimized by matching frequencies in driving and sensing modes. The scale factor and linearity error extracted by calculated capacitance have been changed with various shapes condition unless the area of sensing electrodes and the mass of the gyroscope have been fixed. The mass ratio of gimbal and wheel structure is varied to minimize the linearity error. [ABSTRACT FROM AUTHOR]

Purpose: Adjunctive ganglionated plexi (GP) ablation may improve success rates for treatment of atrial fibrillation (AF) when combined with pulmonary vein (PV) isolation. Existing meta-analyses on GP ablation have included observational studies and have not incorporated more recent randomized clinical trial data. Moreover, the impact of AF subtype (paroxysmal vs. persistent) on outcomes of GP ablation has not been well established.Methods: We performed a meta-analysis of randomized controlled trials (RCTs) comparing GP ablation + pulmonary vein (PV) isolation versus PV isolation alone according to the subtype of AF. The primary endpoint was freedom from sustained AF or atrial tachyarrhythmia (AT) after a single procedure.Results: Across four RCTs, 718 patients (358 and 360 that underwent GP ablation + PV isolation [intervention] vs. PV isolation alone [control], respectively) were included in the study. Mean left atrial size and left ventricular ejection fraction were 45.7 mm and 54.8%, respectively. Among paroxysmal AF patients, GP ablation was linked to significantly higher freedom from AT/AF (75.8 vs. 60.0% for the intervention vs. control arms respectively; OR [95% CI]: 2.22 [1.36-3.61], P = 0.001). Among persistent AF patients, GP ablation was associated with a non-significant trend towards higher rates of freedom from AT/AF (54.7 vs. 43.3% for the intervention vs. control arms respectively; OR [95% CI]: 1.55 [0.96-2.52], P = 0.08). In all cases, heterogeneity was found to be low (I 2 of 32% or lower).Conclusions: Compared to PV isolation alone, GP ablation + PV isolation is associated with better outcomes in patients with paroxysmal AF and without significant structural heart disease. [ABSTRACT FROM AUTHOR]

Lithium iron phosphate (LiFePO4) micro-particles (MPs) were synthesized under hydrothermal condition for fabrication of cathode materials based on LiFePO4 MPs/multi-walled carbon nanotube (MWCNT) nanocomposites. Influence of reaction time for the hydrothermal process on structural, morphological, and electrochemical behavior was investigated. Crystal quality was confirmed by X-ray diffraction (XRD) together with Raman analysis. Micrometer-scale seeds and capsule-shaped morphology were observed. Such nanocomposite cathodes based on LiFePO4 MPs/MWCNT were prepared by surface-engineered tape casting technique. The well-crystallized material composed of densely aggregated MPs and interconnected with MWCNTs led to excellent volumetric Li storage properties at a current rate of 0.1 mVs−1 between 2.5 to 4.3 V. However, the half-cell analysis does not show reasonable capacity values, which may be due to the larger particle size and morphology of synthesized LiFePO4, resulting in limiting ionic transportation and electronic conduction path. [ABSTRACT FROM AUTHOR]

Post-earnings announcement drift (PEAD) which was first identified over 40 years ago seems to be as much alive today as it ever was. Numerous attempts have been made to explain its continued existence. In this paper we provide evidence to support a new explanation: that the PEAD is a reflection of the level of market uncertainty and sentiment that prevails during the post-announcement period. The overriding conclusion from our analysis is that both uncertainty and sentiment play a central role in determining investor behaviour and it is this behaviour that ultimately determines the pricing that is observed in financial markets. [ABSTRACT FROM AUTHOR]

This paper investigates the relevance of the Ricardian Equivalence theorem for the relationship between the budget deficit and real interest rate. In contrast to the existing literature, we focus on regime-change over a long study period and consider nonlinearities. Using a Markov regime-switching model applied to two centuries of annual data, we find evidence that the US economy switches between a Ricardian Equivalence regime, characterized by an insignificant relationship between the adjusted primary budget deficit and real long-term interest rate, and a regime characterized by the traditional view of a positive relationship. We also find evidence that the transition probabilities between regimes are time-varying insofar as a weaker level of economic activity, a lower real interest rate differential between the US and abroad, or higher national debts, is associated with a weaker relationship between budget deficits and interest rates. [ABSTRACT FROM AUTHOR]

Background: The histology of epithelial 'borderline lesions' of the breast, which have features in between atypical ductal hyperplasia (ADH) and ductal carcinoma in situ (DCIS), is well described, but the clinical behavior is not. This study reports subsequent ipsilateral breast events (IBE) in patients with borderline lesions compared with those with DCIS. Methods: Patients undergoing breast-conserving surgery for borderline lesions or DCIS from 1997 to 2010 were identified from a prospective database. IBE was defined as the diagnosis of subsequent ipsilateral DCIS or invasive ductal carcinoma. Results: A total of 143 borderline-lesion patients and 2,328 DCIS patients were identified. Median follow-up was 2.9 and 4.4 years, respectively. 7 borderline-lesion and 172 DCIS patients experienced an IBE. 5 year IBE rates were 7.7 % for borderline lesions and 7.2 % for DCIS ( p = .80). 5 year invasive IBE rates were 6.5 and 2.8 %, respectively ( p = .25). Similarly, when analyses were restricted to patients who did not receive radiotherapy, or endocrine therapy, or both, borderline-lesion and DCIS patients did not demonstrate statistically significant differences in rates of IBE or invasive IBE. Conclusions: When compared with DCIS, borderline lesions do not demonstrate lower rates of IBE or invasive IBE. Despite 'borderline' histology, a 5 year IBE rate of 7.7 % and an invasive IBE rate of 6.5 % suggest that the risk of future carcinoma is significant and similar to that of DCIS. [ABSTRACT FROM AUTHOR]

Studies the joint effect of diversification and intervaling on the skewness and kurtosis of eleven international stock market indexes with a holding period spanning from one to six months. Abnormal distribution of stock returns; Non-reduction of skewness or kurtosis with diversification; Absence of gain derived by a rational investor from international diversification.