QUANTITATIVE ANALYTICAL RESULTS ON TOPOGRAPHIC FEATURE OF THE VIETNAM’S CONTINENTAL SHELF WITHIN COORDINATES 11.7 - 14.00 AND 109.5 - 110.20

This paper presents some analytical results of bathymetry data according to three maps: Three dimensions (3D), slope, aspect on the continental slope and shelf area in the central part of Vietnam within the coordinates of 11.7 - 14.00 and 109.5 - 110.20. The obtained results have reflected clearly the geomorphic characteristics in this area. For example, on the 3D map, the continental slope exists three steps at the depths of 500 - 700 m, 1,250 m, and 1,500 - 1,700 m, running along the meridian 109.70, about 250 km long. These results are also shown on the slope and aspect map. On the slope map, from the depth of about 250 m to the first step base, the slope angle varies within 5 - 200 and from the first step base to second step base, the slope angle varies within 5 - 100; In the remaining part, the slope angle varies within 2 - 80. The other analytical results from the aspect map are also shown clearly, the aspect direction on the wall of three slope steps varies from 50 to 1000, reflecting the topographic slope towards the east, where is abyssal plain. The existence of Pliocene - Quaternary sediments along with steep continental slope caused landslide phenomenon in this area

ЭКСПЕРИМЕНТАЛЬНЫЕ РЕЗУЛЬТАТЫ АНАЛИЗА КОЛИЧЕСТВЕННОЙ КОРРЕЛЯЦИИ ЧАСТОТЫ РАСПРЕДЕЛЕНИЯ ТРЕЩИНОВАТОСТИ НА ПРИМЕРЕ ИЗУЧЕНИЯ ПРОВИНЦИИ КУАНГНИН (ВЬЕТНАМ)

This paper presents the experimental results of analyzing the quantitative correlation of fracture distribu‐ tion at 10 survey sites on the Co To‐Thanh Lan islands, Quang Ninh province, Viet Nam. The obtained results show that most fracture correlation coefficients are over 0.80. The high correlation values among the survey sites reflect well the geodynamic conditions of the tectonic activity phases. These results confirm the significance of the correla‐ tion method in analyzing the structural geology and geotechnics.Представлены экспериментальные результаты анализа количественной корреляции частоты распределения трещиноватости по десяти изученным участкам на островах Ко‐То и Тань‐Лан в провинции Куангнин (Вьетнам). Полученные результаты показывают, что большинство коэффициентов корреляции трещиноватости превышают 0.80. Высокая корреляция значений по изученным участкам хорошо отражает геодинамическую обстановку на этапах тектонической активности. Результаты подтверждают значение метода корреляция для анализа структурной геологии и геотехнических работ

Elemental Analysis of Contaminated Biomass Ashes for Phytomining of Rare Earth Elements

Phytomining of rare earth elements (REEs) provides a potential possibility for metal recovery at brownfields where conventional mining technique is not reasonable or profitable. The holistic concept of phytomining is instituted from three scientific sectors. Phytoextraction is the first stage referred to accumulation of REEs in plants. This is followed by the enrichment process aiming to elevate metal concentration into solid remains. Eventually, extraction technology is applied to reclaim these valuable metals from the bio-ores. The main goal of this study is to identify a possible location for REEs phytomining, which lays the groundwork for further investigations. To do that, different woody biomass from disparate contaminated spots was harvested and examined. A brownfield land located in Gyöngyösoroszi, Hungary has been selected based on the elemental analysis of ash samples obtained from the incineration of the collected plants at 500 °C. The outcomes also preliminarily indicate the viability of phytomining in recovering REEs

Numerical and Experimental Study on the Grinding Performance of Ti-Based Super-Alloy

The experiments of the surface grinding of Ti-6Al-4V grade 5 alloy (Ti-64) with a resin-bonded cubic Boron Nitride (cBN) grinding wheel are performed in this research to estimate the influence of cutting parameters named workpiece infeed speed, Depth of Cut (DOC), cooling condition on the grinding force, force ratio, and specific energy. A finite element simulation model of single-grain grinding of Ti-64 is also implemented in order to predict the values of grinding forces and temperature. The experimental results show that an increase of workpiece infeed speed creates higher intensified cutting forces than the DOC. The grinding experiments under wet conditions present slightly lower tangential forces, force ratio, and specific energy than those in dry grinding. The simulation outcomes exhibit that the relative deviation of simulated and experimental forces is in the range of 1-15%. The increase in feed rate considerably reduces grinding temperature, while enhancement of DOC elevates the heat generation in the cutting zone

High school teachers’ pedagogical beliefs in English as a foreign language writing instruction

Writing in a foreign language is deemed to be the most difficult language skill to learners, especially at high school level. Consequently, its teaching has become a challenging task for high school teachers in the Vietnamese context. Teacher beliefs related literature indicates that what teachers do in the classroom is directly governed by what they think and believe. Thereby, the current study adopted features of a survey research design to examine the English as a Foreign Language (EFL) high school teachers’ beliefs about writing and its teaching. A sample of seventy six EFL teachers from the eight selected high schools situated in Ho Chi Minh City was recruited for the current survey. The beliefs of EFL writing instruction of these teachers were elicited through two instruments of eighteen–item questionnaires and semi–structured interviews. Then the questionnaires were quantitatively analyzed and the interviews were qualitatively analyzed. Results of the study showed that most of the participants held different orientations about writing skill, teacher roles and its teaching. The study was closed by a brief conclusion of key findings

Elemental Analysis of Contaminated Biomass Ashes for Phytomining of Rare Earth Elements

Phytomining of rare earth elements (REEs) provides a potential possibility for metal recovery at brownfields where conventional mining technique is not reasonable or profitable. The holistic concept of phytomining is instituted from three scientific sectors. Phytoextraction is the first stage referred to accumulation of REEs in plants. This is followed by the enrichment process aiming to elevate metal concentration into solid remains. Eventually, extraction technology is applied to reclaim these valuable metals from the bio-ores. The main goal of this study is to identify a possible location for REEs phytomining, which lays the groundwork for further investigations. To do that, different woody biomass from disparate contaminated spots was harvested and examined. A brownfield land located in Gyöngyösoroszi, Hungary has been selected based on the elemental analysis of ash samples obtained from the incineration of the collected plants at 500 °C. The outcomes also preliminarily indicate the viability of phytomining in recovering REEs

TAXONOMIC IDENTITY OF ARISAEMA CONDAOENSE (ARACEAE) BASED ON NEW MORPHOLOGICAL AND MOLECULAR DATA

Arisaema condaoense V.D. Nguyen was described as a new species from Con Dao National Park, Ba Ria–Vung Tau Province, Vietnam in 2000. However, this species has been suspected of being a form of Arisaema roxburghii Kunth, a species widespread in the whole Indochina and Malay Peninsula. This was due to the original description based on dried specimens with male inflorescences only. Morphological characteristics of female inflorescences, which are of taxonomical importance to identify the species, have not been known. In June 2015, we re-sampled the plant in Con Dao National Park with both male and female inflorescences for detailed examination of morphological characteristics. Besides, the matK gene of the chloroplast genome of this species was sequenced to analyse its phylogenetic relationship with other Arisaema species. The gathered morphological and molecular data indicate that A. condaoense is certainly a distinct species, not a synonym of A. roxburghii. The noted morphological characteristics also provide key differences to distinguish A. condaoense from two other morphologically close species of sect. Fimbriata (i.e A. maxwellii from Thailand and A. pierreanum from Vietnam which also share yellow spathes and several other characteristics in common), which are supported by the molecular data. Thus, the species is endemic to Con Dao National Park in Ba Ria–Vung Tau Province, Vietnam. Furthermore, this study allows us revising the description of A. condaoense with, for the first time, supplemental key taxonomic characteristics and illustrating colourful photographs taken from the fresh materials. A key to all eight known Vietnamese species of sect. Fimbriata is also given

Adoptive immunotherapy induces CNS dendritic cell recruitment and antigen presentation during clearance of a persistent viral infection

Given the global impact of persistent infections on the human population, it is of the utmost importance to devise strategies to noncytopathically purge tissues of infectious agents. The central nervous system (CNS) poses a unique challenge when considering such strategies, as it is an immunologically specialized compartment that contains a nonreplicative cell population. Administration of exogenously derived pathogen-specific memory T cells (referred to as adoptive immunotherapy) to mice burdened with a persistent lymphocytic choriomeningitis virus (LCMV) infection from birth results in eradication of the pathogen from all tissues, including the CNS. In this study, we sought mechanistic insights into this highly successful therapeutic approach. By monitoring the migration of traceable LCMV-specific memory CD8+ T cells after immunotherapy, it was revealed that cytotoxic T lymphocytes (CTLs) distributed widely throughout the CNS compartment early after immunotherapy, which resulted in a dramatic elevation in the activity of CNS antigen-presenting cells (APCs). Immunotherapy induced microglia activation as well as the recruitment of macrophages and dendritic cells (DCs) into the brain parenchyma. However, DCs emerged as the only CNS APC population capable of inducing memory CTLs to preferentially produce the antiviral cytokine tumor necrosis factor-α, a cytokine demonstrated to be required for successful immunotherapeutic clearance. DCs were also found to be an essential element of the immunotherapeutic process because in their absence, memory T cells failed to undergo secondary expansion, and viral clearance was not attained in the CNS. These experiments underscore the importance of DCs in the immunotherapeutic clearance of a persistent viral infection and suggest that strategies to elevate the activation/migration of DCs (especially within the CNS) may facilitate pathogen clearance

Fear of travelling after COVID-19: The moderation effect of social distancing

COVID-19 has caused unparalleled public dread, which will most certainly impede tourist business recovery once the epidemic is gone. This research investigates the causes of the general public's epidemic travel anxiety, as well as how individuals impose self-protection, coping, and resilience with travel. The study blends theories such as protection motive theory, coping theory, and resilience theory to achieve the research goal. The primary data came from an online poll of 322 Southeast Asian travelers. According to the findings, the magnitude and vulnerability of the danger might induce "travel dread," which leads to protection motivation and precautionary travel behaviors during the pandemic. The findings also demonstrate that social distancing has memory consequences. In other words, individuals who willingly engaged in social separation during the pandemic are more likely to continue doing so in the post-COVID period since their long-term behavior has been influenced.Tomas Bata University in Zlín, TBU; Finance Authority of Maine, FAM

FedDCT: Federated Learning of Large Convolutional Neural Networks on Resource Constrained Devices using Divide and Co-Training

We introduce FedDCT, a novel distributed learning paradigm that enables the usage of large, high-performance CNNs on resource-limited edge devices. As opposed to traditional FL approaches, which require each client to train the full-size neural network independently during each training round, the proposed FedDCT allows a cluster of several clients to collaboratively train a large deep learning model by dividing it into an ensemble of several small sub-models and train them on multiple devices in parallel while maintaining privacy. In this co-training process, clients from the same cluster can also learn from each other, further improving their ensemble performance. In the aggregation stage, the server takes a weighted average of all the ensemble models trained by all the clusters. FedDCT reduces the memory requirements and allows low-end devices to participate in FL. We empirically conduct extensive experiments on standardized datasets, including CIFAR-10, CIFAR-100, and two real-world medical datasets HAM10000 and VAIPE. Experimental results show that FedDCT outperforms a set of current SOTA FL methods with interesting convergence behaviors. Furthermore, compared to other existing approaches, FedDCT achieves higher accuracy and substantially reduces the number of communication rounds (with $4-8$ times fewer memory requirements) to achieve the desired accuracy on the testing dataset without incurring any extra training cost on the server side.Comment: Under review by the IEEE Transactions on Network and Service Managemen