Geomagnetic Secular Variation Prediction with Thermal Heterogeneous Boundary Conditions

It has long been conjectured that thermal heterogeneity at the core-mantle boundary (CMB) affects the geodynamo substantially. The observed two pairs of steady and strong magnetic flux lobes near the Polar Regions and the low secular variation in the Pacific over the past 400 years (and perhaps longer) are likely the consequences of this CMB thermal heterogeneity. There are several studies on the impact of the thermal heterogeneity with numerical geodynamo simulations. However, direct correlation between the numerical results and the observations is found very difficult, except qualitative comparisons of certain features in the radial component of the magnetic field at the CMB. This makes it difficult to assess accurately the impact of thermal heterogeneity on the geodynamo and the geomagnetic secular variation. We revisit this problem with our MoSST_DAS system in which geomagnetic data are assimilated with our geodynamo model to predict geomagnetic secular variations. In this study, we implement a heterogeneous heat flux across the CMB that is chosen based on the seismic tomography of the lowermost mantle. The amplitude of the heat flux (relative to the mean heat flux across the CMB) varies in the simulation. With these assimilation studies, we will examine the influences of the heterogeneity on the forecast accuracies, e.g. the accuracies as functions of the heterogeneity amplitude. With these, we could be able to assess the model errors to the true core state, and thus the thermal heterogeneity in geodynamo modeling

Using SpF to Achieve Petascale for Legacy Pseudospectral Applications

Pseudospectral (PS) methods possess a number of characteristics (e.g., efficiency, accuracy, natural boundary conditions) that are extremely desirable for dynamo models. Unfortunately, dynamo models based upon PS methods face a number of daunting challenges, which include exposing additional parallelism, leveraging hardware accelerators, exploiting hybrid parallelism, and improving the scalability of global memory transposes. Although these issues are a concern for most models, solutions for PS methods tend to require far more pervasive changes to underlying data and control structures. Further, improvements in performance in one model are difficult to transfer to other models, resulting in significant duplication of effort across the research community. We have developed an extensible software framework for pseudospectral methods called SpF that is intended to enable extreme scalability and optimal performance. Highlevel abstractions provided by SpF unburden applications of the responsibility of managing domain decomposition and load balance while reducing the changes in code required to adapt to new computing architectures. The key design concept in SpF is that each phase of the numerical calculation is partitioned into disjoint numerical kernels that can be performed entirely inprocessor. The granularity of domain decomposition provided by SpF is only constrained by the datalocality requirements of these kernels. SpF builds on top of optimized vendor libraries for common numerical operations such as transforms, matrix solvers, etc., but can also be configured to use open source alternatives for portability. SpF includes several alternative schemes for global data redistribution and is expected to serve as an ideal testbed for further research into optimal approaches for different network architectures. In this presentation, we will describe our experience in porting legacy pseudospectral models, MoSST and DYNAMO, to use SpF as well as present preliminary performance results provided by the improved scalability

Lysosomal biogenesis and function in osteoclasts: a comprehensive review

Lysosomes serve as catabolic centers and signaling hubs in cells, regulating a multitude of cellular processes such as intracellular environment homeostasis, macromolecule degradation, intracellular vesicle trafficking and autophagy. Alterations in lysosomal level and function are crucial for cellular adaptation to external stimuli, with lysosome dysfunction being implicated in the pathogenesis of numerous diseases. Osteoclasts (OCs), as multinucleated cells responsible for bone resorption and maintaining bone homeostasis, have a complex relationship with lysosomes that is not fully understood. Dysregulated function of OCs can disrupt bone homeostasis leading to the development of various bone disorders. The regulation of OC differentiation and bone resorption for the treatment of bone disease have received considerable attention in recent years, yet the role and regulation of lysosomes in OCs, as well as the potential therapeutic implications of intervening in lysosomal biologic behavior for the treatment of bone diseases, remain relatively understudied. This review aims to elucidate the mechanisms involved in lysosomal biogenesis and to discuss the functions of lysosomes in OCs, specifically in relation to differentiation, bone resorption, and autophagy. Finally, we explore the potential therapeutic implication of targeting lysosomes in the treatment of bone metabolic disorders

Prenatal Detection of Aneuploidy and Imbalanced Chromosomal Arrangements by Massively Parallel Sequencing

Fetal chromosomal abnormalities are the most common reasons for invasive prenatal testing. Currently, G-band karyotyping and several molecular genetic methods have been established for diagnosis of chromosomal abnormalities. Although these testing methods are highly reliable, the major limitation remains restricted resolutions or can only achieve limited coverage on the human genome at one time. The massively parallel sequencing (MPS) technologies which can reach single base pair resolution allows detection of genome-wide intragenic deletions and duplication challenging karyotyping and microarrays as the tool for prenatal diagnosis. Here we reported a novel and robust MPS-based method to detect aneuploidy and imbalanced chromosomal arrangements in amniotic fluid (AF) samples. We sequenced 62 AF samples on Illumina GAIIx platform and with averagely 0.01× whole genome sequencing data we detected 13 samples with numerical chromosomal abnormalities by z-test. With up to 2× whole genome sequencing data we were able to detect microdeletion/microduplication (ranged from 1.4 Mb to 37.3 Mb of 5 samples from chorionic villus sampling (CVS) using SeqSeq algorithm. Our work demonstrated MPS is a robust and accurate approach to detect aneuploidy and imbalanced chromosomal arrangements in prenatal samples

Prevalence of the Cryptosporidium Pig Genotype II in Pigs from the Yangtze River Delta, China

Background: Cryptosporidium spp. is prevalent globally, pigs are an important Cryptosporidium reservoir. In China, little data regarding rates of Cryptosporidium infections in pigs are available. The present study was therefore aimed at characterizing the distribution of Cryptosporidium species in pigs from two different cities, Shaoxing and Shanghai, from the Yangtze River delta. Methodology/Principal Findings: Nested PCR to amplify the 18S rRNA locus on DNA extracted from fecal samples (n = 94) revealed the positive rate of Cryptosporidium in pigs from two cities was approximately 17.0%. The positive rates in Shanghai and Shaoxing were 14.3 % and 25.0 % respectively. Amplified sequences were verified by sequencing. The identified strain belonged to the C. pig genotype II using BLAST analysis in the NCBI database. Conclusion/Significance: Our finding of Cryptosporidium pig genotype II in pigs in the Yangtze River delta area suggests that pig farms in this region must be considered a public health threat and proper control measures be introduced

Web-Based Education at Conventional Universities in China: A Case Study

With advances in information and communication technology (ICT), Web-based education has become an increasingly popular instructional mode all over the world. In recent years, the Chinese government has authorized a total of 45 universities to offer Web-based educational programs. One is China Central Radio and Television University, the Open University in China. The other 44 universities are all leading conventional universities. This case study is intended to provide a descriptive analysis of Web-based educational practices at the 44 leading conventional universities, by focusing on the current state of Web-based education in China and its discernible trends for the future. It is hoped this analysis of Web-based educational efforts in China will provide some insight for other countries

Web-Based Education at Conventional Universities in China: A Case Study

With advances in information and communication technology (ICT), Web-based education has become an increasingly popular instructional mode all over the world. In recent years, the Chinese government has authorized a total of 45 universities to offer Web-based educational programs. One is China Central Radio and Television University, the Open University in China. The other 44 universities are all leading conventional universities. This case study is intended to provide a descriptive analysis of Web-based educational practices at the 44 leading conventional universities, by focusing on the current state of Web-based education in China and its discernible trends for the future. It is hoped this analysis of Web-based educational efforts in China will provide some insight for other countries

Distributed Multi-target Localization System Based on Optical Wavelength Division Multiplexing Network

A distributed multi-target localization system based on optical Wavelength Division Multiplexing (WDM) network is demonstrated. The wideband orthogonal waveforms are generated by introducing the chaotic OptoElectronic Oscillator (OEO). The optical WDM network is introduced to transmit the wideband signals from multiple distributed transmitting and receiving units to the central station for processing, and the accurate localization of multiple targets is achieved based on the time of arrival localization method. The multiple optical carriers are generated at the central station, the complex processing to achieve the highprecision of the target localization is supported by the resources at the central station, and the remote transmitting and receiving units are simplified. Moreover, a proof of concept of the distributed multi-target localization system based on optical WDM network is obtained. The localization system comprising two transmitters and two receivers is experimentally established. The orthogonal chaotic waveforms with the frequency range of 3.1～10.6 GHz are successfully generated from the chaotic OEOs. The two-dimensional localization of two targets is realized via the maximum positioning error of 7.09 cm. Additionally, the reconfiguration of the system is experimentally verified

Two-Step Hydrothermal Synthesis of Well-Dispersed (Na0.5Bi0.5)TiO3 Spherical Powders

(Na0.5Bi0.5)TiO3 (NBT) powders that have well-dispersed, uniform particle size and well-developed spherical shape were successfully prepared by a two-step hydrothermal synthesis method. Nanosized TiO2 powders were firstly synthesized by a hydrothermal method, and then the TiO2 particles are used as a raw material to synthesize NBT powders. It was found that by using the TiO2 nanoparticles as Ti source, the well-dispersed spherical NBT powders with about 200 nm in size could be obtained at 200°C for 4 h with a low mineralizer concentration of 6 mol/L NaOH in the second step. The formation of spherical NBT powders can be explained by first generating nuclei on the surface of TiO2 nanoparticles via in situ crystallization mechanism and then crystal growing and agglomerating by dissolution-recrystallization mechanism