Structural and Optoelectronic Properties of CdSe Tetrapod Nanocrystals for Bulk Heterojunction Solar Cell Applications

Semiconducting CdSe tetrapod nanoparticles were prepared, and their structural and optical properties were examined. The surface capping molecule, octylphosphonic acid, was replaced with butylamine after the particle synthesis. The exchange of surface ligands changed the physical properties of the nanocrystals, which resulted in a slight decrease in the nanoparticles size. The effects of changing surface ligands of CdSe tetrapod nanocrystals on the structural and optoelectronic properties were investigated, and it was found that the surfactant of nanoparticles could affect the device performance by enhancing the charge carrier separation at the active layer interfaces. Power conversion efficiency of the bulk heterojunction solar cells having the structure of glass/ITO/PEDOT:PSS/(CdSe + PCPDTBT)/Al was improved from 1.21% to 1.52% with the use of ligand-exchanged nanoparticles

Impacts of Economic Development on the Living Conditions of Ethnic Minority People in the Border Region of Northern Vietnam

Purpose:   In this study, we examine the effects of the economic development policies of the Vietnamese government on the living conditions of ethnic minority people in the border region of Northern Vietnam.   Theoretical framework: We examine the impact of economic changes, societal changes, and environmental improvements on the living conditions of ethnic minority people in the border region of Northern Vietnam.   Design/Methodology/Approach: The collected data was subsequently cleaned and analyzed using Partial Least Squares Structural Equation Modelling (PLS-SEM) with the aid of SPSS 20 software.     Findings: The results show that the current Vietnamese government’s policies on developing agriculture, industry, trade, and service for ethnic minority people have a diverse impact on their living conditions. In general, agriculture, trade, and service are major fields that benefit the living conditions of ethnic minorities. In contrast, the industry seems to have no effects on improving the standard of living of ethnic minority people in Northern Vietnam.   Research, practical & social implications: The results of this study provide suggestion to Vietnamese government on promoting living conditions of ethnic minority people in the border region of Northern Vietnam.   Originality/Value: This is the first paper evaluates the impact of the economic development policies of the Vietnamese government on the living conditions of ethnic minority people in the border region of Northern Vietnam

Zooplankton biodiversity in the biosphere reserve of Cu Lao Cham - Hoi An, 2015–2016

Zooplankton samples in the biosphere reserve of Cu Lao Cham - Hoi An were collected at 20 stations belonging to 3 ecosystems: Mangrove palm - seagrass, transition area and coral reef in rainy season (11/2015) and dry season (6/2016) to determine biodiversity of the biosphere reserve of Cu Lao Cham - Hoi An.  161 species belonging to 16 zooplankton groups were recognized, copepoda was a dominant group with 92 species, followed by cladocera (15 species) and tunicata (13 species). Mangrove palm - sea grass had a different zooplankton structure compared with transition area and coral reef with a lower number of species and similarity index about 40%. The average density of zooplankton in study areas in dry season (24,559 ± 24,700 inds.m-3) were 4 times higher than in rainy season (6,124 ± 6.554 inds.m-3) and dominated by copepoda. The euryhaline cladocera (Bosmina longirostris), freshwater cladocera (Ceriodaphnia rigaudi) and freshwater copepoda (Microcyclops varicans) were dominant in mangrove palm - seagrass ecosystem. Meanwhile, in coral reef ecosystem, the small copepods (genus Oncaea, Oithona) and Tunicata were dominant. Biodiversity indices were low in mangrove - palm and increase from transition area to coral reef ecosystem

One-pot preparation of alumina-modified polysulfone-graphene oxide nanocomposite membrane for separation of emulsion-oil from wastewater

In recent years, polysulfone-based nanocomposite membranes have been widely used for contaminated water treatment because they comprise properties such as high thermal stability and chemical resistance. In this study, a polysulfone (PSf) nanocomposite membrane was fabricated using the wet-phase inversion method with the fusion of graphene oxide (GO) and alumina (Al2O3) nanoparticles. We also showed that GO-Al2O3 nanoparticles were synthesised successfully by using a one-pot hydrothermal method. The nanocomposite membranes were characterised by Fourier transform infrared (FT-IR), scanning electron microscopy (SEM), nitrogen adsorption-desorption isotherms, energy-dispersive X-ray spectroscopy (EDX), thermogravimetric analysis (TGA), and water contact angle. The loading of GO and Al2O3 was investigated to improve the hydrophilic and oil rejection of the matrix membrane. It was shown that by using 1.5 wt.% GO-Al2O3 loaded in polysulfone, ~74% volume of oil was separated from the oil/water emulsion at 0.87 bar and 30 min. This figure was higher than that of the process using the unmodified membrane (PSf/GO) at the same conditions, in which only ~60% volume of oil was separated. The pH, oil/water emulsion concentration, separation time, and irreversible fouling coefficient (FRw) were also investigated. The obtained results suggested that the GO-Al2O3 nanoparticles loaded in the polysulfone membrane might have potential use in oily wastewater treatment applications

A case of hepatic cyst-induced internal jugular venous thrombosis

• Echocardiography can demonstrate hepatic cyst–induced right atrial compression. • Hepatic cyst–induced blood flow stasis can cause internal jugular venous thrombus. • Laparoscopic deroofing of hepatic cysts is a safe and effective treatment

Results of acute cerebral infarction treatment with hyperbaric oxygen therapy, 2020–2022

Background: Cerebral stroke is the third leading cause of death after cardiovascular disease, cancerand the leading cause of disability for patients. Hyperbaric oxygen is a non-drug treatment that hasthe potential to improve brain function for patients with ischaemic stroke. The objective of this study wasto evaluate the results of treatment of acute cerebral infarction with hyperbaric oxygen therapy (HBOT).Materials and methods: This was a case-control study. One hundred ninety-five patients diagnosed withcerebral infarction, with signs of onset within 24 hours, were treated at the Centre for Underwater Medicineand Hyperbaric Oxygen of Vietnam National Institute of Maritime Medicine during the period from January2020 to December 2022. Study group included 100 patients with acute cerebral infarction treated witha combination of HBOT and medication and reference group included 95 patients treated by medicationonly (antiplatelets drugs, statins, control of associated risks factors)Results: After 7 days of treatment with hyperbaric oxygen (HBO), symptoms such as headache, dizziness,nausea, sensory disturbances, and Glasgow score of the study group improved better than that of the referencegroup (p < 0.01). Movement recovery in the study group was better than the reference group:the percentage of patients with mild and moderate paralysis in the study group increased higher than thatof the reference group (86.0% and 68.4%), the degree of complete paralysis of the study group decreasedmore than that of the reference group (14.0% and 31.6%). The degree of independence in daily activitiesin the study group was better than the reference group. In the study group, the percentage of patients withcomplete independence in daily life increased from 27.0% to 84.0%. In the reference group, the rate of patientswho were independent in their daily activities increased from 37.9% to 51.6%. The average numberof treatment days of the study group was 10.32 ± 2.41 days and it the reference group 14.51 ± 3.24 days.Conclusions: Hyperbaric oxygen therapy is a non-drug treatment with many good effects in the treatmentof cerebral infarction, especially acute cerebral infarction. HBOT reduces and improves functional symptoms,improves mobility, and reduces treatment time for patients

A Large-Scale Study of a Sleep Tracking and Improving Device with Closed-loop and Personalized Real-time Acoustic Stimulation

Various intervention therapies ranging from pharmaceutical to hi-tech tailored solutions have been available to treat difficulty in falling asleep commonly caused by insomnia in modern life. However, current techniques largely remain ill-suited, ineffective, and unreliable due to their lack of precise real-time sleep tracking, in-time feedback on the therapies, an ability to keep people asleep during the night, and a large-scale effectiveness evaluation. Here, we introduce a novel sleep aid system, called Earable, that can continuously sense multiple head-based physiological signals and simultaneously enable closed-loop auditory stimulation to entrain brain activities in time for effective sleep promotion. We develop the system in a lightweight, comfortable, and user-friendly headband with a comprehensive set of algorithms and dedicated own-designed audio stimuli. We conducted multiple protocols from 883 sleep studies on 377 subjects (241 women, 119 men) wearing either a gold-standard device (PSG), Earable, or both concurrently. We demonstrate that our system achieves (1) a strong correlation (0.89 +/- 0.03) between the physiological signals acquired by Earable and those from the gold-standard PSG, (2) an 87.8 +/- 5.3% agreement on sleep scoring using our automatic real-time sleep staging algorithm with the consensus scored by three sleep technicians, and (3) a successful non-pharmacological stimulation alternative to effectively shorten the duration of sleep falling by 24.1 +/- 0.1 minutes. These results show that the efficacy of Earable exceeds existing techniques in intentions to promote fast falling asleep, track sleep state accurately, and achieve high social acceptance for real-time closed-loop personalized neuromodulation-based home sleep care.Comment: 33 pages, 8 figure

Investment in human capital and labor productivity in Vietnam : the case study on small and medium enterprises

This paper investigates the importance of training in Small and Medium Enterprises (SMEs) in Vietnam as a basis for improving productivity. Current training courses are ineffective, and need to be associated with practical work. Trainers need appropriate experience as well as knowledge of how to organize classes. SME Support Centres are evaluated in terms of trainers and training: findings show that training organization for SMEs should be classified by types of trainees; courses for employees should focus on particular skills; and policies should encourage management skills training as well. Development of new curriculum materials is urgent

Detection and monitoring of cancers with biosensors in Vietnam

Biosensors are able to provide fast, accurate and reliable detec-tions and monitoring of cancer cells, as well as to determine the effectiveness of anticancer chemotherapy agents in cancer treatments. These have attracted a great attention of research communities, especially in the capabilities of detecting the path-ogens, viruses and cancer cells in narrow scale that the conven-tional apparatus and techniques do not have. This paper pre-sents technologies and applications of biosensors for detections of cancer cells and related diseases, with the focus on the cur-rent research and technology development about biosensors in Vietnam, a typical developing country with a very high number of patients diagnosed with cancers in recent years, but having a very low cancer survival rate. The role of biosensors in early detections of diseases, cancer screening, diagnosis and treat-ment, is more and more important; especially it is estimated that by 2020, 60-70% new cases of cancers and nearly 70% of cancer deaths will be in economically disadvantaged countries. The paper is also aimed to open channels for the potential R&D collaborations with partners in Vietnam in the areas of innovative design and development of biosensors in particular and medical technology devices in general