Approximate cloaking for time-dependent Maxwell equations via transformation optics

We study approximate cloaking using transformation optics for electromagnetic waves in the time domain. Our approach is based on estimates of the degree of visibility in the frequency domain for all frequencies in which the frequency dependence is explicit. The difficulty and the novelty analysis parts are in the low and high frequency regimes. To this end, we implement a variational technique in the low frequency domain, and multiplier and duality techniques in the high frequency domain. Our approach is inspired by the work of Nguyen and Vogelius on the wave equation

A Fuzzy LQR PID Control for a Two-Legged Wheel Robot with Uncertainties and Variant Height

This paper proposes a fuzzy LQR PID control for a two-legged wheeled balancing robot for keeping stability against uncertainties and variant heights. The proposed control includes the fuzzy supervisor, LQR, PID, and two calibrations. The fuzzy LQR is conducted to control the stability and motion of the robot while its posture changes with respect to time. The fuzzy supervisor is used to adjust the LQR control according to the robotic height. It consists of one input and one output. The input and output have three membership functions, respectively, to three postures of the robot. The PID control is used to control the posture of the robot. The first calibration is used to compensate for the bias value of the tilting angle when the robot changes its posture. The second calibration is applied to compute the robotic height according to the hip angle. In order to verify the effectiveness of the proposed control, a practical robot with the variant height is constructed, and the proposed control is embedded in the control board. Finally, two experiments are also conducted to verify the balancing and moving ability of the robot with the variant posture

THE IMPLEMENTATION OF COMMUNICATIVE LANGUAGE TEACHING IN THE CONTEXT OF ONLINE LEARNING: A LITERATURE REVIEW

With the occurrence of the COVID-19 crisis, there has been dramatically growth and adoption of online education. As a consequence of the epidemic, institutes have been compulsory to close, and teaching and learning have changed fully to home studying. As a result, numerous educational institutions have adopted online teaching and learning on a massive scale. To combine the Communicative Language Teaching (CLT) approach with a framework of computer-assisted language learning seems to be the best strategy during a coronavirus outbreak. This study offers a survey of the literature on Communicative Language Teaching in the situation of online teaching and studying. This paper begins with an overview, definition, and characteristics of CLT. It then examines how CLT can be beneficial in a virtual classroom: advantages and disadvantages. Besides, it discusses the approaches to using CLT in online teaching and learning. This paper's goal is to provide an effective overview that can be used for online language instruction. The study will add to our understanding of Communicative Language Teaching and its use in an online setting.  Article visualizations

Serum free light-chain concentration and relationship with some characteristics of patients with multiple myeloma

Introduction: Quantifying serum free light-chain is a valuable test to determine the risk at the time of diagnosis, assess the response to treatment, and monitor the recurrence of multiple myeloma. Objective: To investigate the characteristics of serum free light-chain concentration and its relationship with some clinical and subclinical characteristics in patients with multiple myeloma. Methods: Descriptive, retrospective, non-controlled study was conducted, in 74 patients with multiple myeloma. All patients were completed with quantitative tests serum free light-chain κ, and serum free light-chain λ. Results: Intact immunoglobulin multiple myeloma accounted for most patients (81%). Most patients had abnormal serum free light-chain at the time of diagnosis (98.6%). High serum free light-chain concentration was correlated with M protein concentration > 3 g/dL (p< 0.05) and there was no statistically significant correlation between high serum free light-chain and other clinical and subclinical features. Conclusion: Most patients with multiple myeloma have an elevated serum free light-chain at admission time. Correlation of high serum free light-chain with increased serum M protein was noted

Morphological and molecular characteristics of Panax sp. (Araliaceae) from Phu Xai lai leng mountain, Nghe An province, Vietnam

Seven sterile and young specimens of Panax sp. were collected in Phu Xai Lai Leng silicat mountain, the highest mountain  peak in central Vietnam. Morphologically, they resemble P. stipuleanatus and P. bipinnatifidus. However, they have stipules and leaflets that are not bipinnatifid. The ITS-DNA sequences of Panax sp. from Phu Xai Lai Leng are identical and exhibit a close relationship with P. stipuleanatus from Tam Duong district, Lai Chau province with strong bootstrap support (98%). Noticeably, these two taxa  are different by 2 nucleotides. A collection of standard specimens including inflorescence, infructescence, flowers and ripe fruits of Panax from Phu Xai Lai Leng is needed to determine its taxonomic status.

Rebellious youth and ineffective advice: A study of Vietnamese adolescents’ capability to deal with digital threats

The digital era brings various benefits to adolescents. However, operating on the digital environment without sufficient knowledge and skills will expose them to multiple types of risks, especially in the country with low digital safety education rate like Vietnam. The current study examines factors that can contribute to cultivating adolescents’ digital resilience using the information-processing reasoning of the Mindsponge Theory. A UNESCO dataset of 1061 Vietnamese high school students was analyzed using the Bayesian Mindsponge Framework analytics. It is found that adolescents’ daily Internet usage frequency, parents’ Internet safety guidance, and teachers’ safety guidance are positively associated with digital resilience. However, the effects of parents’ and teachers’ Internet safety guidance on digital resilience are conditional on the daily Internet usage frequency. Parents’ guidance only enhances adolescents’ digital resilience if they use the Internet less than four hours per day. In contrast, the positive effect of teachers’ guidance on adolescents’ digital resilience becomes stronger when the students spend more time on the Internet (more than 1 hour). Based on these findings, we suggest that adolescents can learn to minimize risks and protect themselves by exposing more to the digital environment. Parents’ and teachers’ supports are important in enhancing adolescents’ capability to deal with digital threats, but types of supports need to be carefully considered to avoid reverse impacts on adolescents’ resilience

Dosimetric and radiobiological comparison between conventional and hypofractionated breast treatment plans using the Halcyon system

PurposeThe objective of this research is to compare the efficacy of conventional and hypofractionated radiotherapy treatment plans for breast cancer patients, with a specific focus on the unique features of the Halcyon system.Methods and materialsThe study collected and analyzed dose volume histogram (DVH) data for two groups of treatment plans implemented using the Halcyon system. The first group consisted of 19 patients who received conventional fractionated (CF) treatment with a total dose of 50 Gy in 25 fractions, while the second group comprised 9 patients who received hypofractionated (HF) treatment with a total dose of 42.56 Gy in 16 fractions. The DVH data was used to calculate various parameters, including tumor control probability (TCP), normal tissue complication probability (NTCP), and equivalent uniform dose (EUD), using radiobiological models.ResultsThe results indicated that the CF plan resulted in higher TCP but lower NTCP for the lungs compared to the HF plan. The EUD for the HF plan was approximately 49 Gy (114% of its total dose) while that for the CF plan was around 53 Gy (107% of its total dose).ConclusionsThe analysis suggests that while the CF plan is better at controlling tumors, it is not as effective as the HF plan in minimizing side effects. Additionally, it is suggested that there may be an optimal configuration for the HF plan that can provide the same or higher EUD than the CF plan

Effectiveness of perindopril/amlodipine fixed-dose combination in the treatment of hypertension: a systematic review

Background: Uncontrolled blood pressure is a major risk factor for cardiovascular diseases. Fixed-dose combination (FDC) therapy offers a promising approach to addressing this challenge by providing a convenient single-tablet solution that enhances the effectiveness of blood pressure control. In our systematic review, we assess the effectiveness of perindopril/amlodipine FDC in managing blood pressure.Methods: We conducted a comprehensive search across four primary electronic databases, namely, PubMed, Virtual Health Library (VHL), Global Health Library (GHL), and Google Scholar, as of 8 February 2022. Additionally, we performed a manual search to find relevant articles. The quality of the selected articles was evaluated using the Study Quality Assessment Tools (SQAT) checklist from the National Institute of Health and the ROB2 tool from Cochrane.Results: Our systematic review included 17 eligible articles. The findings show that the use of perindopril/amlodipine FDC significantly lowers blood pressure and enhances the quality of blood pressure control. Compared to the comparison group, the perindopril/amlodipine combination tablet resulted in a higher rate of blood pressure response and normalization. Importantly, perindopril/amlodipine FDC contributes to improved patient adherence with minimal side effects. However, studies conducted to date have not provided assessments of the cost-effectiveness of perindopril/amlodipine FDC.Conclusion: In summary, our analysis confirms the effectiveness of perindopril/amlodipine FDC in lowering blood pressure, with combination therapy outperforming monotherapy and placebo. Although mild adverse reactions were observed in a small subset of participants, cost-effectiveness assessments for this treatment remain lacking in the literature

Global, regional, and national burden of disorders affecting the nervous system, 1990–2021: a systematic analysis for the Global Burden of Disease Study 2021

BackgroundDisorders affecting the nervous system are diverse and include neurodevelopmental disorders, late-life neurodegeneration, and newly emergent conditions, such as cognitive impairment following COVID-19. Previous publications from the Global Burden of Disease, Injuries, and Risk Factor Study estimated the burden of 15 neurological conditions in 2015 and 2016, but these analyses did not include neurodevelopmental disorders, as defined by the International Classification of Diseases (ICD)-11, or a subset of cases of congenital, neonatal, and infectious conditions that cause neurological damage. Here, we estimate nervous system health loss caused by 37 unique conditions and their associated risk factors globally, regionally, and nationally from 1990 to 2021.MethodsWe estimated mortality, prevalence, years lived with disability (YLDs), years of life lost (YLLs), and disability-adjusted life-years (DALYs), with corresponding 95% uncertainty intervals (UIs), by age and sex in 204 countries and territories, from 1990 to 2021. We included morbidity and deaths due to neurological conditions, for which health loss is directly due to damage to the CNS or peripheral nervous system. We also isolated neurological health loss from conditions for which nervous system morbidity is a consequence, but not the primary feature, including a subset of congenital conditions (ie, chromosomal anomalies and congenital birth defects), neonatal conditions (ie, jaundice, preterm birth, and sepsis), infectious diseases (ie, COVID-19, cystic echinococcosis, malaria, syphilis, and Zika virus disease), and diabetic neuropathy. By conducting a sequela-level analysis of the health outcomes for these conditions, only cases where nervous system damage occurred were included, and YLDs were recalculated to isolate the non-fatal burden directly attributable to nervous system health loss. A comorbidity correction was used to calculate total prevalence of all conditions that affect the nervous system combined.FindingsGlobally, the 37 conditions affecting the nervous system were collectively ranked as the leading group cause of DALYs in 2021 (443 million, 95% UI 378–521), affecting 3·40 billion (3·20–3·62) individuals (43·1%, 40·5–45·9 of the global population); global DALY counts attributed to these conditions increased by 18·2% (8·7–26·7) between 1990 and 2021. Age-standardised rates of deaths per 100 000 people attributed to these conditions decreased from 1990 to 2021 by 33·6% (27·6–38·8), and age-standardised rates of DALYs attributed to these conditions decreased by 27·0% (21·5–32·4). Age-standardised prevalence was almost stable, with a change of 1·5% (0·7–2·4). The ten conditions with the highest age-standardised DALYs in 2021 were stroke, neonatal encephalopathy, migraine, Alzheimer's disease and other dementias, diabetic neuropathy, meningitis, epilepsy, neurological complications due to preterm birth, autism spectrum disorder, and nervous system cancer.InterpretationAs the leading cause of overall disease burden in the world, with increasing global DALY counts, effective prevention, treatment, and rehabilitation strategies for disorders affecting the nervous system are needed