A short-loop algorithm for quantum Monte Carlo simulations

We present an algorithmic framework for a variant of the quantum Monte Carlo operator-loop algorithm, where non-local cluster updates are constructed in a way that makes each individual loop smaller. The algorithm is designed to increase simulation efficiency in cases where conventional loops become very large, do not close altogether, or otherwise behave poorly. We demonstrate and characterize some aspects of the short-loop on a square lattice spin-1/2 XXZ model where, remarkably, a significant increase in simulation efficiency is observed in some parameter regimes. The simplicity of the model provides a prototype for the use of short-loops on more complicated quantum systems.Comment: 9 pages, 9 figures: new FSS discussion adde

Supersolidity from defect-condensation in the extended boson Hubbard model

We study the ground state phase diagram of the hard-core extended boson Hubbard model on the square lattice with both nearest- (nn) and next-nearest-neighbor (nnn) hopping and repulsion, using Gutzwiller mean field theory and quantum Monte Carlo simulations. We observe the formation of supersolid states with checkerboard, striped, and quarter-filled crystal structures, when the system is doped away from commensurate fillings. In the striped supersolid phase, a strong anisotropy in the superfluid density is obtained from the simulations; however, the transverse component remains finite, indicating a true two-dimensional superflow. We find that upon doping, the striped supersolid transitions directly into the supersolid with quarter-filled crystal structure, via a first-order stripe melting transition.Comment: Revtex 4, 6 pages, 9 figure

A framework of energy consumption modelling for additive manufacturing using Internet of Things

The topic of ‘Industry 4.0’ has become increasingly popular in manufacturing and academia since it was first published. Under this trending topic, researchers and companies have pointed out many related capabilities required by current manufacturing systems, such as automation, interoperability, consciousness, and intelligence. Additive manufacturing (AM) is one of the most popular applications of Industry 4.0. Although AM systems tend to become increasingly automated and worry less, the issue of energy consumption still attracts attention, even in the Industry 4.0 era, and is related to many processing factors depending on different types of AM system. Therefore, defining the energy consumption behaviour and discovering more efficient usage methods in AM processes is established as being one of the most important research targets. In this paper, an Internet of Things (IoT) framework is designed for understanding and reducing the energy consumption of AM processes. A huge number and variety of real-time raw data are collected from the manufacturing system; this data is analysed by data analytical technologies, combining the material attributes parameter and design information. This data is uploaded to the cloud where more data will be integrated for discovering the energy consumption knowledge of AM systems. In addition, a case study is also presented in this paper, which a typical AM system is focused on the target system (EOS P700). The raw data is collected and analysed from this process. Then, based on the IoT framework, a novel energy consumption analysis proposal is proposed for this system specifically

THE RISING WORLD OF MICRORNAS:ONCOGENES AND TUMOR SUPPRESSORS IN CANCER

The sequencing of the human genome has revealed that the bulk of the genome is transcribed into noncoding RNAs, including microRNAs. These microRNAs are deregulated in cancer where they regulate a wide array of functions associated with tumorigenesis. Glioblastoma (GBM) is the most common and aggressive primary intracranial tumor of the adult brain. miRNAs are short noncoding RNAs that broadly regulate gene expression. They exert their actions via transcriptional, post-transcriptional, and epigenetic mechanisms that are poorly understood. Numerous miRNAs are deregulated in GBM, where their expression levels can serve as biomarkers. They can act as either oncogenes or tumor suppressors in GBM by targeting the expression of numerous tumor-suppressors or oncogenes. miRNAs regulate all GBM malignancy aspects including cell proliferation, survival, motility, migration, invasion, angiogenesis, cancer stem cell biology, microenvironment modulation, immune escape, and therapy resistance. MiRNAs can also be secreted via exosomes or microvesicles in body .uids, where they can be used as diagnosis and/or prognosis biomarkers. Considering their deep involvement in GBM malignancy, numerous studies are currently undertaken to exploit miRNAs as therapeutic agents or targets. This short review summarizes the biogenesis, deregulation, functions, mechanisms of action, and clinical applications of miRNAs in GB

Perceived importance and levels of technical English communication skills among stakeholders in engineering fields

The purposes of this study were to examine stakeholders’ perceptions of the importance of technical English communication skills in engineering and academic teachers and industry professionals’ perceptions of current engineering students’ and graduates’ levels of technical communication skills. Survey questionnaires were designed to collect data from different research participants. The data were subsequently analysed using descriptive statistics. The study identified a discrepancy between students’ self-perceived performance on technical English communication skills and their perceived standards of these skills required by the programmes in which they were enrolled. Technical communication skills, including writing in engineering genres, essays and technical reports, reading and speaking, were viewed to be fairly important for their academic success. The findings also indicated that the students’ abilities in writing in engineering genres, and essays and technical report writing were perceived to be below the standards. In addition, the study highlighted that industry professionals viewed the technical communication skills of engineering graduates working in the engineering sectors as inadequate. Based on these results, it is vitally important to develop a tailor-made enhancement course to cater for the specific needs of engineering students, including technical communication skills for their study programmes and to prepare them for workplace needs of engineers in the near future

Cryptic diversity in Tranzscheliella spp. (Ustilaginales) is driven by host switches

Species of Tranzscheliella have been reported as pathogens of more than 30 genera of grasses (Poaceae). In this study, a combined morphological and molecular phylogenetic approach was used to examine 33 specimens provisionally identified as belonging to the T. hypodytes species complex. The phylogenetic analysis resolved several well-supported clades that corresponded to known and novel species of Tranzscheliella. Four new species are described and illustrated. In addition, a new combination in Tranzscheliella is proposed for Sorosporium reverdattoanum. Cophylogenetic analyses assessed by distance-based and event-cost based methods, indicated host switches are likely the prominent force driving speciation in Tranzscheliella

Modelling thin film growth in the Ag-Ti system

Simulations of thin lm growth in the Ag-Ti system are presented using molecular dynamics combined with an adaptive kinetic Monte Carlo method (AKMC) with a modi ed embedded atom potential t to ab initio data for the surface energies. For the model, atoms are assumed to deposit normally with a kinetic energy of 1-3 eV, with a typical deposition rate of around 10 monolayers per second, similar to what might be expected in a sputter deposition process. For the growth of Ti on the Ag (100) and Ag (111) surfaces, the Ti adatoms prefer to exchange with the original surface layer atoms creating a mixed Ag/Ti surface. On a silver substrate, up to four mixed layers need to be formed before a pure Ti layer is obtained. Conversely, simulations of Ag depositing onto Ti (0001) showed that in the initial phase of growth, the Ag adatoms prefer to be separated before a complete rst layer of Ag was obtained in a close-packed structure. The implementation of a super-basin method within AKMC allowed the simulation of 0.4s of Ti growth on the Ag substrates, with up to 3 new layers added