•The direction-dependent interband optical conductivity of monolayer black phosphorus in the presence magnetic field and temperature is investigated.•Observation of decreasing optical transition in ...both directions when the temperature is increased.•Temperature- and frequency-dependent optical conductivity do not change significantly with perpendicular magnetic field independent of the orientation.
The paper presents a theoretical investigation of the temperature and an out-of-plane Zeeman magnetic field effects on the interband optical conductivity of phosphorene. The electronic states are calculated with the tight-binding Hamiltonian and to compute the optical conductivity, the Kubo formalism is employed. The main result is that the multiple bands due to the perpendicular Zeeman splitting of the energy levels lead to the multiple resonance structures of the optical conductivity. It is found that the strong anisotropic interband optical conductivity of pristine phosphorene keeps the anisotropic feature when the temperature is increased. Importantly, our results show that the optical properties can be externally tuned via a magnetic field. In particular, when the magnetic field is applied, the unique anisotropic property breaks down and there is a little to no sign for temperature- and orientation-dependent transitions. The scientific soundness of findings is useful for practical aspects of phosphorene in spintronic.
We investigate the influence of phonon confinement on the optically detected magneto-phonon resonance (ODMPR) effect and ODMPR line-width in quantum wells. The ODMPR conditions as functions of the ...well's width and the photon energy are also obtained. The shifts of ODMPR peaks caused by the confined phonon are discussed. The numerical result for the GaAs/AlAs quantum well shows that in the two cases of confined and bulk phonons, the line-width (LW) decreases with increasing well's width and increases with increasing temperature. Furthermore, in the small range of the well's width, the influence of phonon confinement plays an important role and cannot be neglected in reaching the ODMPR line-width.
•Absorption power is calculated in square quantum wells taking into account the phonon confinement effect.•Optically detected magneto-phonon resonance line-width (ODMPRLW) as profiles of curves is determined.•The ODMPRLW increases with increasing temperature and decreases with increasing well's width.•The ODMPRLW in the case of confined phonons is greater than it is in the case of bulk phonons.
: COVID-19 is a respiratory disease caused by a novel coronavirus (SARS-CoV-2) and causes substantial morbidity and mortality. There is currently no vaccine to prevent COVID-19 or therapeutic agent ...to treat COVID-19. This clinical trial is designed to evaluate chloroquine as a potential therapeutic for the treatment of hospitalised people with COVID-19. We hypothesise that chloroquine slows viral replication in patients with COVID-19, attenuating the infection, and resulting in more rapid decline of viral load in throat/nose swabs. This viral attenuation should be associated with improved patient outcomes.
: The study will start with a 10-patient prospective observational pilot study following the same entry and exclusion criteria as for the randomized trial and undergoing the same procedures. The main study is an open label, randomised, controlled trial with two parallel arms of standard of care (control arm) versus standard of care with 10 days of chloroquine (intervention arm) with a loading dose over the first 24 hours, followed by 300mg base orally once daily for nine days. The study will recruit patients in three sites in Ho Chi Minh City, Vietnam: the Hospital for Tropical Diseases, the Cu Chi Field Hospital, and the Can Gio COVID hospital. The primary endpoint is the time to viral clearance from throat/nose swab, defined as the time following randomization until the midpoint between the last positive and the first of the negative throat/nose swabs. Viral presence will be determined using RT-PCR to detect SARS-CoV-2 RNA.
The results of the study will add to the evidence-based guidelines for management of COVID-19. Given the enormous experience of its use in malaria chemoprophylaxis, excellent safety and tolerability profile, and its very low cost, if proved effective then chloroquine would be a readily deployable and affordable treatment for patients with COVID-19.
Clinicaltrials.gov NCT04328493 31/03/2020.
We investigate the influence of phonon confinement described by the slab mode model on the optically detected magneto-phonon resonance (ODMPR) effect and ODMPR line-width in parabolic quantum wells ...by using the operator projection. The ODMPR conditions as functions of the well's parameters and the photon energy are also obtained. The shifts of ODMPR peaks caused by the confined phonon are discussed. The numerical result for a specific quantum well shows that in the two cases of confined and bulk phonons, the line-width (LW) is sensitive to the change of the confinement frequency, and temperature. Furthermore, the influence of slab mode phonon plays an important role and cannot be neglected in reaching the ODMPR line-width for all range of the well's confinement frequency.
We investigate the influence of phonon confinement on the optically detected electrophonon resonance (ODEPR) effect and ODEPR line-width in quantum wells. The obtained numerical result for the GaAs ...AlAs quantum well shows that the ODEPR line-widths depend on the well's width and temperature. Besides, in the two cases of confined and bulk phonons, the linewidth (LW) decreases with the increase of well's width and increases with the increase of temperature. Furthermore, in the small range of the well's width, the influence of phonon confinement plays an important role and cannot be neglected in considering the ODEPR line-width.
Nghiên cứu này được thực hiện để thu thập thông tin về tính khả thi và hiệu quả của việc xây dựng và áp dụng quy trình theo định hướng dạy học STEM cho môn Sinh học 10. Đa số giáo viên (GV) đánh giá ...quy trình đã giúp họ thiết kế bài học STEM tốt hơn, tự tin hơn khi áp dụng và đưa ra một số ý kiến góp ý về quy trình. Tuy quy trình đã được nhóm cụ thể hóa nhưng GV vẫn còn gặp một số khó khăn và hạn chế trong việc được áp dụng rộng rãi. Để có cái nhìn chi tiết hơn về tình trạng này, việc tiến hành các nghiên cứu sâu hơn được đề xuất để tìm hiểu nguyên nhân ảnh hưởng đến tính khả thi của quy trình và mức độ vận dụng kiến thức của học sinh (HS).
Nghiên cứu này trình bày phương pháp chế tạo mô hình tự học lái ô tô thông qua mô phỏng các thao tác lái trên sa hình theo tiêu chuẩn cấp bằng lái xe quốc gia. Phần cứng của mô hình gồm các hệ thống ...truyền lực, hệ thống hệ thống chuyển động và điều khiển được bố trí tương tự xe thực tế. Ngoài ra, thiết bị được bố trí màn hình có kích thước 32 inch, dây đai an toàn, ghế ngồi có thể điều chỉnh được, âm thanh cảnh báo khi có va chạm. Sa hình trong thiết kế được mô phỏng tương tự sa hình thực tế thông qua phần mềm Euro Truck Simulator 2. Sản phẩm của nghiên cứu này giúp người sử dụng rèn luyện các kĩ năng: lái, điều khiển bàn đạp ly hợp, bàn đạp ga, bàn đạp phanh và kĩ năng xử lý tình huống lái xe trên đường. Đặc biệt, mô hình giúp tiết kiệm thời gian, chi phí học lái và giá thành thiết bị thấp mà vẫn đạt hiệu quả lái tương đương.
Mpox was diagnosed in 2 women returning to Vietnam from the United Arab Emirates. The monkeypox viruses belonged to an emerging sublineage, A.2.1, distinct from B.1, which is responsible for the ...ongoing multicountry outbreak. Women could contribute to mpox transmission, and enhanced genomic surveillance is needed to clarify pathogen evolution.
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