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Correction: Retraction: Tanshinone IIA Inhibits HIF-1α and VEGF Expression in Breast Cancer Cells via mTOR/p70S6K/RPS6/4E-BP1 Signaling Pathway
NSF terminates huge number of grants and stops awarding new ones
High front-to-back ratio metasurface antenna with single-layer and compact size for WLAN applications
This paper proposes a novel high front-to-back ratio (FBR) metasurface (MS) antenna with single-layer and compact size characteristics. The proposed design consists of a 2 × 2 unit-cell MS radiating layer, which is capacitively coupled with a directed-fed crossed patch in the same layer. Accordingly, compact design with single-layer MS antenna can be obtained. It is worth noting that the proposed configuration is different from the conventional MS antenna, which is commonly designed with multiple layers, leading to high profile and complicated structure. Finally, a substrate integrated waveguide cavity is employed to improve the FBR of the proposed design. A prototype with overall dimensions of 0.52 λ × 0.52 λ × 0.03 λ achieved measured operating bandwidth of about 10.6%. Despite having compact size, the proposed antenna always performs high broadside gain of better than 5.2 dBi and high front-to-back ratio of better than 16 dBi entire the operating bandwidth. These operation characteristic distinguishes the proposed design from the other MS antennas with more complicated structures.
Impact of spectacle use on academic performance among Vietnamese adolescents with reduced visual acuity and myopia: A school-based study
Objectives Untreated cataracts and uncorrected refractive errors are the leading causes of vision impairment worldwide. Timely correction of refractive errors can significantly improve visual function and daily life. This study examined the impact of spectacle use on the academic performance of schoolchildren with reduced visual acuity (VA) and myopia. Methods This cross-sectional study included 647 students from five secondary schools in Hue City, Vietnam. Students underwent comprehensive eye examinations, including VA, autorefractometry, and axial length measurements, and a structured questionnaire was completed. The primary outcome was academic performance, based on grade point average (GPA), math, and literature scores. Generalized linear models were utilized to examine the association between spectacle use and students’ academic performance. Results The mean spherical equivalent was −0.92 ± 1.62 diopters, and the mean axial length was 23.32 ± 1.07 mm. The prevalence of reduced VA (uncorrected VA ≤ 7/10) and myopia (spherical equivalent ≤ −0.5 diopters) was 23.2% and 48.7%, respectively. Almost two-thirds of myopic students did not wear spectacles. Spectacle use was found to be significantly associated with an increased GPA (β = 0.462; 95% confidence interval = 0.108–0.816), math scores (β = 0.517; 95% confidence interval = 0.015–1.020), and literature scores (β = 0.438; 95% confidence interval = 0.074–0.802) among students with reduced VA, and with increased literature scores (β = 0.277; 95% confidence interval = 0.046–0.509) among students with myopia. Conclusions Refractive errors, particularly myopia, are major health concerns among secondary school students in Vietnam. Despite the need for corrective spectacles, many students do not wear them, exacerbating their vision problems. This study highlights the benefits of spectacles in improving academic performance for students with reduced VA and myopia.
Prevention and control of multidrug-resistance tuberculosis in Ethiopia: Patients’ perspectives from the Oromia region
Background Multi-drug-resistant tuberculosis (MDR-TB) is one of the biggest challenges worldwide to end tuberculosis. It is vital to understand the challenges and opportunities of patients during MDR-TB treatment to enhance prevention and control efforts. The gap in research on the challenges and opportunities of patients during the screening, diagnosis, referral, and follow-up of MDR-TB prompted this study. Purpose The purpose of the study was to assess the challenges and opportunities for patients with MDR-TB during the diagnosis and treatment of MDR-TB in the Oromia region of Ethiopia. Methods A qualitative approach was applied. The data were collected from 30 MDR-TB patients from 1 to 30 April 2022 using semi-structured interviews after written informed consent was signed by each participant to understand the challenges and opportunities of MDR-TB treatment. Data was analysed by thematic analysis using ATLAS.ti software. Result This article identifies challenges that include delays in diagnosis and treatment initiation due to inadequate diagnostic services, physical inaccessibility, and financial problems faced by patients to pay for transport, food, diagnosis, and accommodation. Other challenges included lack of psychosocial support, shortage of healthcare providers, poor communication, drug side effects, and interruption of food and housing support. In addition, participants mentioned opportunities, which include the availability of free diagnosis, treatment, and admission; availability of transport; food and housing allowance; and use of an ambulance for referral. Conclusion This study filled a research gap in Ethiopia by identifying challenges and opportunities during the MDR-TB treatment program. The MDR-TB treatment program should focus on improving inadequate screening and resources, shortage of healthcare providers, delays in the referral process, and non-compliance of patients.
Government regulation or market mechanism? A study on the collaborative innovation pathways of the emergency industry based on evolutionary game models
Promoting collaborative innovation within the emergency industry has become a crucial task, which is of great significance for enhancing emergency response capabilities and ensuring public safety. On the basis of considering the economic attributes of the emergency industry and the uncertainty characteristics of market returns, this study constructs an evolutionary game model for collaborative innovation among emergency enterprises, universities and research institutions (UR), and government departments, which are the main entities considered. It analyzes the evolutionary process of the strategy choices and equilibrium states of different entities, thereby revealing the key factors and intrinsic mechanisms affecting collaborative innovation pathways. The study results indicate that the economic attributes of the emergency industry and the uncertainty of market returns are key factors that constrain the collaborative innovation and development of the emergency industry. The economic attributes of the emergency industry determine the applicable boundaries of government regulation and market mechanisms in the collaborative innovation process of the emergency industry. Due to the “marketization paradox” in the emergency industry with weak economic attributes, and the fact that emergency enterprises and UR are more likely to face the “prisoner’s dilemma” in the process of collaborative innovation, collaborative innovation via the government regulation-driven pathway is more feasible; In contrast, for the emergency industry with strong economic attributes, the government can effectively strengthen the market-oriented profit mechanism by enhancing public safety emergency awareness, thereby promoting collaborative innovation driven by market mechanisms in the emergency industry. Based on the analysis of the effects of different regulatory measures, it is found that government procurement is more effective than R&D subsidy policy. R&D subsidies are not only ineffective in avoiding the “prisoner’s dilemma” in the collaborative innovation process, but also have a “double-edged sword” effect. Excessive subsidy intensity can actually inhibit the enthusiasm of emergency enterprises and UR for collaborative innovation. When government departments adopt regulatory actions, focusing on balancing incentive and punitive measures, and emergency enterprises and UR focus on establishing a reasonable benefit distribution mechanism, which can more effectively improve the efficiency of collaborative innovation and form a good situation of win-win for all parties. The above findings provide certain decision-making references for the promotion of innovative development in the emergency industry.
Retraction: Efficient lung cancer detection using computational intelligence and ensemble learning
Retraction: Ubiquitination increases Parkin activity to promote Autophagic α-Synuclein Clearance
Daily briefing: Chimp societies drum to a distinct beat
Floral visitation of European honey bees and hoverflies in selected cultivated cucurbitaceous crops in Morogoro, Eastern-Central Tanzania
Cucurbit production in many parts of the world is constrained by the absence of effective pollinators. Due to the decline of European honey bees (Apis mellifera), main pollinators of cucurbits, there is a need to explore other cucurbits flowers visiting insects to supplement pollination services and for their conservation. Studies were carried out in the two agroecological zones of Morogoro Region, Eastern - Central Tanzania. We assessed visitation abundance, visitation frequency and visitation rate of four cucurbits flowers visiting insects under the family Syrphidae [Eristalinus megacephalus, Mesembrius caffer, Paragus borbonicus and Toxomerus floralis] and A. mellifera on cucumber (Cucumis sativus), watermelon (Citrullus lanatus) and squash (Cucurbita moschata). Field trials were conducted in a 5 × 3 × 2 × 2 factorial arrangement in a randomized complete block design for two seasons. Results showed significant effects of the interaction between agroecological zones × cucurbit species × season × flowers visiting insects on visitation abundance, visitation frequency and visitation rate (p < 0.0001) of flower visiting species. Apis mellifera was the dominant species in cucurbit flowers at both agroecological zones during the two growing seasons. Given its relatively higher visitation, T. floralis is a promising hoverfly species to be explored for its role in the pollination of C. sativus and C. lanatus. Agroecological zone, season and cucurbit species determined the visitation of European honey bees and hoverflies on cucurbits flowers. Cucurbit growers are suggested to employ management practices on farms that favour the abundance and foraging activities of these flower visiting insects for improved and sustainable cucurbit production.
Scientists turn lead into gold
The efficiency of sensory systems in postural control of children with and without hearing or visual impairments
Limited evidence exists on the efficiency of the sensory systems of children with sensory impairment. The purpose of this study was to examine the sensory systems involved in postural control of male children with hearing (HI) or visual impairments (VI) compared to those without HI or VI. Participants aged 9–13 years old (N = 45, Mage = 11.43, SD = 1.5) were placed within one of three equally stratified purposive groups (HI, VI, comparison children). Postural control was measured using a Kistler force plate (with stabilometric parameters: mean velocity in the anterior-posterior (AP) and medial-lateral (ML), standard deviation (SD) velocity in the AP and ML directions, and sway area) applying four different sensory conditions; condition A: standing on two legs on a stable surface with the eyes open and without any sensory interference (assessment of postural control); condition B: standing on two legs on a stable surface with eyes closed and hyper-extension of the head (perturbation of vestibular and visual system: assessment of proprioceptive system); condition C: standing on two legs on an unstable surface with hyper-extension of the head (perturbation of vestibular and proprioception system: assessment of visual system); condition D: standing on two feet on an unstable surface and eyes closed (perturbation of proprioception and visual system: assessment of vestibular system). The results indicated that in the assessment of postural control condition, comparison children had smaller center of pressure (COP) parameters than children with VI and HI (p = 0.001). Also, children with HI had smaller COP parameters compared to VI (p = 0.001). In the assessment of proprioceptive system condition, comparison children had greater COP parameters than children with HI and VI (p = 0.001). In conclusion, comparison children had better postural control than children with VI and HI; and children with HI had better postural control than children with VI. The proprioceptive system of children with VI and HI performed better than comparison children in maintaining postural control. Consequently, children with VI, HI, and comparison children depend on the proprioceptive system more than other sensory systems to maintain postural control.
Fixed points of multivalued convex contractions with application
In this work, we establish fixed point outcomes for single- valued convex contraction type mappings in the context of a b-metric space. Some of the new results are extended for a multivalued convex contraction and an F-convex contraction. Thereby, an analogue of the famous Nadler’s fixed point theorem for a multivalued convex contraction mapping is obtained. The relation among various contractions is presented in a diagram for an insight in this area of investigations. We apply a special case of Theorem 2.11, to solve a nonlinear Fredholm integral equation for a Chatterjea convex contraction.