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Background: Diverse bacterial group behaviors are controlled by quorum sensing, a regulatory network of bacterial gene expression based on cell density, and involving communication through chemical signal molecules called autoinducers. Multidisciplinary research in toxigenic Vibrio cholerae the etiologic agent of cholera, appear to suggest group behavior in the ecology, epidemiology, pathogenesis and transmission of the pathogen. This review summarizes latest advances and known aspects of quorum regulated environmental survival form of V. cholerae, and their role in cholera outbreaks, as well as the significance of this knowledge in tracking the pathogen for prevention of cholera. Main body: Pathogenic V. cholerae naturally exists in aquatic reservoirs, and infects humans, often leading to epidemic outbreaks of cholera. Effective detection and monitoring of the pathogen in surface waters have been a research focus in preventing cholera outbreaks. However, in the aquatic reservoirs, V. cholerae persists mostly in a quiescent state referred to as viable but non-culturable (VBNC), or conditionally viable environmental cells (CVEC), which fail to grow in routine bacteriological culture. The presence of CVEC can, however, be observed by fluorescent antibody based microscopy, and they appear as clumps of cells embedded in an exopolysaccharide matrix. Current studies suggest that CVEC found in water are derived from in-vivo formed biofilms excreted by cholera patients. The transition to CVEC occurs when dilution of autoinducers in water blocks quorum-mediated regulatory responses that would normally disperse the cellular aggregates. Consequently, CVEC are resuscitated to actively growing cells if autoinducers are replenished, either in the laboratory, or naturally by other environmental bacteria or the intestinal microbiota when CVEC are ingested by humans or aquatic animals. Conclusion: Quorum sensing plays a crucial role in the environmental persistence of toxigenic V. cholerae in a latent state, and their periodic emergence to cause cholera outbreaks. Furthermore, the autoinducer driven resuscitation of these cells may be a basis for improving the detection of V. cholerae in water samples, and monitoring V. cholerae in their aquatic reservoirs in cholera endemic areas. [ABSTRACT FROM AUTHOR]

Harvesting energy from nonlinear systems has been at the centre of research in the energy harvesting community. Many such proposed systems are single nonlinear harvester. While these systems show an increase in bandwidth of harvesting frequency, overall, they are not effective enough in power generation. This article studies power harvesting and frequency bandwidth characteristics of an array of harvesters. Multiple harvesters are considered with linear and nonlinear coupling between the harvesters. The phenomena of internal resonance (IR) and stochastic resonance (SR) are reported. The IR in multiple coupled nonlinear harvesters is explored using multiple-scale analysis. A parametric study is conducted to demonstrate the effect of coupling strength, frequency mistuning, innate nonlinearity and other parameters. The parametric study helped establish effective ways to increase bandwidth. Moreover, a stochastically loaded linearly coupled bistable harvester array is numerically analysed to find the effect of coupling strength and array size on the phenomenon of SR and on the system's harvesting performance. Through these studies, the potential of multiple coupled nonlinear harvesters in enhanced energy harvesting is demonstrated under both harmonic and stochastic excitation. This article is part of the theme issue 'Celebrating the 15th anniversary of the Royal Society Newton International Fellowship'. [ABSTRACT FROM AUTHOR]

Background: We evaluated the validity of surrogacy of progression‐free survival (PFS) or time‐to‐progression (TTP) and overall response rate (ORR) in phase II trials of pancreatic ductal adenocarcinoma (PDAC). In addition, we explored the impact of predictive variables on overall survival (OS) and developed an optimal OS model. Methods: We analyzed 1867 clinical endpoint from 619 phase II PDAC trials with a systematic search from PubMed. Endpoint correlations were determined by Spearman's rank correlation. The assessed predictive factors included PFS/TTP, treatment size, therapy type, stage, and previous treatment. The relationship between predictors and OS was explored by a gamma generalized linear model (GLM) with a log‐link function and compared with linear models. Results: The Spearman rank correlation coefficient between PFS/TTP and OS was 0.88 (95% confidence interval [CI] 0.85–0.89; p < 0.0001; n = 610) and between ORR and OS was 0.58 (0.52–0.64; p < 0.0001; n = 514). Model comparison favored the GLM model over the linear model, offering more accurate predictions for higher OS values. Consequently, PFS/TTP was the strongest predictor (pseudo‐R2 = 0.75), with 1 added median PFS/TTP month associated with 13% (95% CI 13%–14%) increase in median OS. Subgroup analysis revealed that chemotherapy conferred significantly longer OS compared to targeted therapy in 1‐Agent and 2‐Agent trials, exhibiting a "very large" and "medium" effect size, respectively (rank biserial, rrb = 0.40 [95% CI 0.22–0.56] and rrb = 0.29 [0.16–0.41], both p < 0.0001), although inconsistent efficacy in 3‐Agent trials (rrb = 0.12 [−0.07–0.30], p = 0.21). Conclusions: PFS/TTP is a more reliable surrogate than ORR and a strong predictor of OS in phase II trials of pancreatic cancer. Moreover, gamma GLM (log‐link function) is a robust tool for modeling positively skewed survival data with non‐constant variance, thus can be applied to other cancers' OS data of such nature. [ABSTRACT FROM AUTHOR]

The crises of the Islamic world revolve around “epistemic colonialism.” So, in order to decolonize the Muslim mind, we must be able to deconstruct the Western episteme, and this involves dissociating ourselves from the Eurocentric knowledge system that gradually became ascendent since the Renaissance through such ideas as progress and modernity. However, this does not mean we need to discontinue dialog with Western thought. Rather it means retrieving and reviving our own intellectual heritage and being able to think with the categories and concepts derived from that heritage. But in light of the postcolonial situation where the intellectual and linguistic connection with one's own tradition is severed, this is a tremendous challenge. What is more, many Muslim intellectuals simply think that Islamic heritage has little relevance to address contemporary challenges. Yet unless Muslims are able to ground their self‐identity in their own intellectual tradition, they will be held captive to the web of epistemic colonialism. They might be comfortable offering their prayers as Muslims, but their mental ambience will be permeated by devastating, Eurocentric ideas. They will hardly be able to overcome their fragmented self‐image. [ABSTRACT FROM AUTHOR]

A Penta band negative permittivity metamaterial using a split disc ring resonator for satellite applications is investigated in this paper. The proposed structure features a double split ring resonator with a split disc resonator attached on top of a high frequency suitable dielectric substrate Rogers RO 4350B (lossy) with a flexible thickness of 0.168 mm. The CST microwave studio 2019 simulator is used to evaluate the performance of the metamaterial structure. At 2.38 GHz (S-band), 6.60 GHz (C-band), 7.32 GHz (C-band), 8.60 GHz (X-band) and 16.34 GHz (Ku-band), the structure offers Penta band resonances of transmission coefficient (S21) with magnitudes of -34.60 dB, -35.39 dB, -30.32 dB, -32.65 dB and − 58.80 dB, respectively. The structure also shows the bandwidths of 0.26, 0.33, 0.24, 0.30 and 3.64 GHz at Penta band resonances. The characteristics of the metamaterial structure are elucidated through the effective medium parameter scenario. To provide additional clarity, electromagnetic field and surface current analysis plots are examined for different resonance frequencies. Negative permittivity has been realized in the frequency ranges of 2.38–3.20 GHz, 6.60–6.86 GHz, 7.32–7.72 GHz, 8.60–9.28 GHz and 16.34–19.76 GHz. The value of the relative permeability has been noticed nearly zero at all resonances. The value of the refractive index has also been perceived negative at all resonances. An effective medium ratio (EMR) of the proposed split disc resonator structure is 10.50 at 2.38 GHz, demonstrating its compactness and efficiency. The ADS software creates an equivalent circuit to verify the CST and HFSS simulator result. Fabrication of the proposed structure was done for experimental validation. The findings demonstrate a close match between simulation results using different simulators and experimental results. Due to its excellent bandwidth and superior EMR, the proposed structure presents a viable option for S, C, X, and Ku satellite bands, as well as for applications requiring antenna gain enhancement. [ABSTRACT FROM AUTHOR]

The purpose of this article is twofold: first, I will reconstruct Mullā Ṣadrā's complex arguments for the soul's immortality based on its immaterial nature. Second and finally, I will briefly probe and assess various epistemological and metaphysical objections against Ṣadrā's immaterialist conception of the soul. Ṣadrā contends that our bodily death marks an awakening to the reality of our consciousness on the plane of the imaginal realm (the imaginal world is an isthmus between the sensible world and the world of intelligible forms). For Ṣadrā, 'death' does not mark an end or discontinuity in human consciousness, rather it signifies an awakening to a new mode of existence in which the soul, having once been the active principle controlling the actions of the physical body, now manifests itself as the passive recipient of the form given to it by its imaginal reality – a reality shaped by the actions it had performed in its earthly, embodied state. Thus, death is seen as the passage of the soul from the sensible to the imaginal world, until the soul unites with the intelligible world (ʿālam al-ʿaql). [ABSTRACT FROM AUTHOR]

Background: We conducted a systematic review aimed to evaluate the effects of non-pharmaceutical interventions within non-healthcare workplaces and community-level workplace closures and lockdowns on COVID-19 morbidity and mortality, selected mental disorders, and employment outcomes in workers or the general population. Methods: The inclusion criteria included randomized controlled trials and non-randomized studies of interventions. The exclusion criteria included modeling studies. Electronic searches were conducted using MEDLINE, Embase, and other databases from January 1, 2020, through May 11, 2021. Risk of bias was assessed using the Risk of Bias in Non-Randomized Studies of Interventions (ROBINS-I) tool. Meta-analysis and sign tests were performed. Results: A total of 60 observational studies met the inclusion criteria. There were 40 studies on COVID-19 outcomes, 15 on anxiety and depression symptoms, and five on unemployment and labor force participation. There was a paucity of studies on physical distancing, physical barriers, and symptom and temperature screening within workplaces. The sign test indicated that lockdown reduced COVID-19 incidence or case growth rate (23 studies, p < 0.001), reproduction number (11 studies, p < 0.001), and COVID-19 mortality or death growth rate (seven studies, p < 0.05) in the general population. Lockdown did not have any effect on anxiety symptoms (pooled standardized mean difference = -0.02, 95% CI: -0.06, 0.02). Lockdown had a small effect on increasing depression symptoms (pooled standardized mean difference = 0.16, 95% CI: 0.10, 0.21), but publication bias could account for the observed effect. Lockdown increased unemployment (pooled mean difference = 4.48 percentage points, 95% CI: 1.79, 7.17) and decreased labor force participation (pooled mean difference = -2.46 percentage points, 95% CI: -3.16, -1.77). The risk of bias for most of the studies on COVID-19 or employment outcomes was moderate or serious. The risk of bias for the studies on anxiety or depression symptoms was serious or critical. Conclusions: Empiric studies indicated that lockdown reduced the impact of COVID-19, but that it had notable unwanted effects. There is a pronounced paucity of studies on the effect of interventions within still-open workplaces. It is important for countries that implement lockdown in future pandemics to consider strategies to mitigate these unintended consequences. Systematic review registration: PROSPERO registration # CRD42020182660. [ABSTRACT FROM AUTHOR]

This study presented a unique, miniaturised asymmetric interconnected vertical stripe (IVS) design for terahertz (THz) frequency applications. Therefore, this research aimed to achieve a frequency response of 0 to 10 THz using a 5 × 5 µm2 Silicon (Si) substrate material. Meanwhile, various parametric examinations were conducted to investigate variations in the performance. For example, the unit cell selection process was carefully examined by using various design structures and modifying the structure by adding split gaps and connecting bars between vertical stripes. Furthermore, the proposed sandwich structure design was used to compute the absorbance and reflectance properties. All the analytical examinations were executed utilising the Computer Simulation Technology (CST) 2019 software. The introduced IVS metamaterial exhibits negative index behaviour and has a single resonance frequency of 5.23 THz with an acceptable magnitude of − 24.38 dB. Additionally, the quadruple-layer IVS structure exhibits optimised transmission coefficient behaviour between 3 and 6 THz and 7 to 9 THz, respectively. However, the magnitude of the transmission coefficient increased with the number of material layers. Besides that, the absorbance study shows that using a quadruple-layer structure obtains unique and promising results. Overall, the proposed asymmetric IVS metamaterial design achieves the required performance by using a compact structure rather than extending the dimensions of the design. [ABSTRACT FROM AUTHOR]

Introduction: In this study, the relationship between the spinnbarkeit, i.e., the stretchability of saliva, and dental caries was investigated. Methods: Dentistry students were divided into a group with more than 2 decayed, missed, and filled teeth (DMFT ≥2, n = 30) and caries-free group (DMFT = 0, n = 36). Results: Unstimulated saliva flow rate, pH, and spinnbarkeit were determined. Salivary spinnbarkeit was significantly lower in the caries-prone group compared to the caries-free group (5.4 ± 3.9 mm vs. 13.5 ± 7.6 mm, respectively, p < 0.001). Conclusion: This suggests that saliva with high spinnbarkeit protects better against dental caries. [ABSTRACT FROM AUTHOR]

A new quad T-shaped triple band metamaterial is presented in this paper containing three resonance frequencies at 5.7 GHz, 9.6 GHz and 12.1 GHz which are covered C, X, and Ku-band, respectively. These three resonance frequencies are observed by high-frequency electromagnetic solver CST (Computer simulation technology) microwave studio at a frequency range of 4–16 GHz with the electric, magnetic and surface current distributions, and the effective parameters are carried out using the robust method from the transmission and reflection coefficient. The junction of four T-shaped conducting layers is introduced wider bandwidth of transmission coefficient from 4.7 to 6.2 GHz, 8.4 to 10.4 GHz, and 11.3 to 13.5 GHz and the symmetric orientation of the split rings exhibits stable responses of EM properties. The proposed metamaterial unit cell has shown a strong accumulation of electric and magnetic field components, where the negative permittivity, negative permeability and negative refractive index are shown at the resonance frequencies of the transmission coefficient. The different angular orientations of the proposed metamaterial with different dielectric constants are analyzed for parametric study. [ABSTRACT FROM AUTHOR]

Rapid urbanization and population growth have increased the need for optimizing the location of health services in highly urbanized countries like Kingdom of Saudi Arabia (KSA). This study employs a multiple-criteria decision making (MCDM) approach, e.g., fuzzy overlay technique by combining the P-Median location-allocation model, for optimizing health services. First, a geodatabase, containing public hospitals, road networks and population districts, was prepared. Next, we investigated the location and services of five public hospitals in Jeddah city of KSA, by using a MCDM model that included a fuzzy overlay technique with a location-allocation model. The results showed that the allocated five hospitals served 94 out of 110 districts in the study area. Our results suggested additional hospitals must be added to ensure that the entire city is covered with timely hospital services. To improve the existing situation, we prioritized demand locations using the maximize coverage (MC) location problem model. We then used the P-Median function to find the optimal locations of hospitals, and then combined these two methods to create the MC-P-Median optimizer. This optimizer eliminated any unallocated or redundant information. Health planners can use this model to determine the best locations for public hospitals in Jeddah city and similar settings. [ABSTRACT FROM AUTHOR]

This work focused on the novel symmetrical left-handed split ring resonator metamaterial for terahertz frequency applications. A compact substrate material known as Silicon with a dimension of 5 µm was adopted in this research investigation. Moreover, several parameter studies were investigated, such as clockwise rotation, array and layer structure designs, larger-scale metamaterials, novel design structure comparisons and electric field distribution analysis. Meanwhile, two types of square-shaped metamaterial designs were proposed in this work. The proposed designs exhibit double and single resonance frequencies respectively, likely at 3.32 and 9.24 THz with magnitude values of − 16.43 and − 17.33 for the first design, while the second design exhibits a response at 3.03 THz with a magnitude value of − 19.90. Moreover, the verification of these results by adopting High-frequency Structure Simulator software indicates only slight discrepancies which are less than 5%. Furthermore, the initial response of the proposed designs was successfully altered by simply rotating the design clockwise or even increasing the dimension of the design. For instance, the first resonance frequency is shifted to the lower band when the first proposed design was rotated 90°. On the other hand, by increasing the size of the metamaterial, more than nine resonance frequencies were gained in each symmetric design. Furthermore, the symmetric metamaterial with a similar width and length of 10 µm dimension was adopted for both design structures to construct an equivalent circuit model by utilising Advanced Design System software. Finally, both unit cell designs were utilised to explore the absorption performances which exhibit four and five peak points. Overall, the altering behaviour by changing physical properties and compact design with acceptable responses become one of the novelties of this research investigation. In a nutshell, the proposed designs can be utilised in terahertz frequency which gives optimistic or advantageous feedback and is relatively suitable for the adopted frequency range. [ABSTRACT FROM AUTHOR]

Aims/Introduction: Our objective was to estimate the prevalence of hyperglycemia at baseline, and identify its predictors among community clinic (CC) users from a selected rural area of Bangladesh. Materials and Methods: This cross‐sectional study partly used the baseline data of implementation research in which a total of 11,244 adults visited the CC, and their blood glucose, blood pressure and anthropometry were evaluated according to 'Action 2' of the World Health Organization (WHO) Package of Essential Noncommunicable Disease Interventions (PEN) protocol 1. Of these, 11,144 had complete information on demography, chronic diseases and their risk factors, which were collected during the implementation of 'Action 1' of WHO PEN protocol 1 at the household level. Hyperglycemia, prediabetes (PreD) and type 2 diabetes were diagnosed using the WHO criteria. Results: Using WHO PEN protocol 1, the estimated baseline prevalence was 12.5% for hyperglycemia, 3.4% for PreD and 9.2% for type 2 diabetes, and was more prevalent among men compared with women. PreD and type 2 diabetes had significantly higher odds ratio (OR >1) of having common risk factors as follows: age ≥40 years (PreD, P < 0.001; type 2 diabetes, P < 0.001), generalized obesity (PreD, P < 0.001; type 2 diabetes, P = 0.005) and hypertension (PreD, P < 0.000; type 2 diabetes, P < 0.001). Furthermore, participants with a family history of diabetes appeared to be a significant predictor of type 2 diabetes (P < 0.001), but not for PreD (P = 0.303). Conclusions: Hyperglycemia, preD and type 2 diabetes showed a comparatively high prevalence among the CC users of the selected rural area. Obesity and hypertension are the key modifiable risk factors that should be reduced using a CC‐centered risk reduction strategy. [ABSTRACT FROM AUTHOR]

Both SARS-CoV-2 and influenza virus can be transmitted by asymptomatic, presymptomatic, or symptomatic infected persons. We assessed effects on work attendance while ill before and during the COVID-19 pandemic in the United States by analyzing data collected prospectively from persons with acute respiratory illnesses enrolled in a multistate study during 2018–2022. Persons with previous hybrid work experience were significantly less likely to work onsite on the day before through the first 3 days of illness than those without that experience, an effect more pronounced during the COVID-19 pandemic than during prepandemic influenza seasons. Persons with influenza or COVID-19 were significantly less likely to work onsite than persons with other acute respiratory illnesses. Among persons with positive COVID-19 test results available by the second or third day of illness, few worked onsite. Hybrid and remote work policies might reduce workplace exposures and help reduce spread of respiratory viruses. [ABSTRACT FROM AUTHOR]

Microalgae have been recognized as promising competitors for bioenergy production, because of their high lipid content and quick biomass development. In this work, freshwater microalgae Scenedesmus dimorphus was cultivated in a synthetic wastewater media with the object of investigating the bioenergy potential by physicochemical characterization. Batch experiments were performed photoautotrophically for biomass generation supplemented with different levels of CO2 concentration. Maximum biomass production was in the limit of 373 mg/L to 587 mg/L under different CO2 feed concentrations. Cultivation of microalgae along with CO2 supplementation found a substantial impact on buildup of lipid in microalgae biomass. Maximum 29% and 32% lipid content were achieved for 2% and 6% CO2 enrichment respectively, under nitrogen-depleted conditions. Fourier transform infrared spectroscopy, thermogravimetric analysis, and carbon, hydrogen, nitrogen, sulfur elemental analyzer instrumental tools were used to perform physicochemical characterization on biomass in order to determine its proximate analysis, ultimate analysis, higher heating value (HHV), and macromolecular composition, The higher heating value (HHV) of Scenedesmus dimorphus biomass achieved 33.26 MJ/kg with almost zero sulfur content. This HHV value is significantly higher than that of other microalgae sp. Moreover, this HHV value is also even higher than that of bituminous coal (24.3 MJ/kg) and other types of lignocellulosic biomass. Scenedesmus dimorphus biomass indicates that it can be a potential fuel feedstock for environmentally friendly bioenergy production. [ABSTRACT FROM AUTHOR]

This study presents the feasibility of implementing commercial-off-the-shelf reciprocating piston compressors for a developed active flow control (AFC) actuation framework to quantify the aerospace relevant performance ramifications of control architecture and compressor operational choices. Three architectures are studied: supply valve metering, exit area metering, and a combined approach. All concepts are studied under varying compressor operation schedules. The analysis framework in this study integrates internal pneumatic actuation and discharge dynamics, an experimentally calibrated compressor pressure and thermal dynamics model, three feedback control architectures, and flight dynamics models. The framework is implemented in simulation to provide a user-friendly tool for linking AFC architecture choices to achievable flight trajectories. Actuator performance is evaluated using actuation time, output, compressor duty cycle, and specific energy consumption. Aircraft tracking performance is evaluated as usable time and slalom centerline deviation. The analysis indicates that a supply-volume-based metering approach is comparatively inefficient concerning an exit-area-based metering, resulting in high flight tracking error. Exit area metering provides the best efficiency and run time with some structural drawbacks, while the combined approach provides the best flight tracking performance at the expense of additional complexity. These results inform the choice of onboard AFC hardware choices. [ABSTRACT FROM AUTHOR]

The effectiveness of therapy in patients with diabetes depends on the correct use of the insulin injection technique. However, despite many established recommendations and evidence that an effective insulin injection technique is essential to improve glycaemic control and minimise the risk associated with diabetes, there is still a need to identify impediments to the insulin injection technique among patients and create awareness among patients and healthcare professionals about the importance of the optimisation of insulin injection techniques. This review focuses on the recent advancements in delivery devices, insulin injection technique teaching methods, monitoring, and complication management and highlights regional best practices and recommendations for optimising injection techniques to improve diabetes outcomes. [ABSTRACT FROM AUTHOR]

Abstract Cashew nut (Anacardium occidentale L.) farmers are facing challenges producing quality nuts due to inadequate knowledge of cashew insect pests and their management practices in Bangladesh. For this reason, a survey of 144 cashew farmers was conducted from June 2020 to December 2022. Tea mosquito bug (70.1%), cashew stem and root borer (52.8%), and apple and nut borer (45.8%) were the top-ranked among 21 insect pest species of cashew. The highest insect pest infestation was observed in the tender leaves (49.8%). Overall, 56.3% farmers noticed 11–20% yield losses caused by insect pests, while 9% of the farmers believed that yield losses could be more than 40% in cashew orchards. Although physical (7.7%) and mechanical (7.6%) pest management tactics, like hand-picking, use of coal tar, kerosene, and yellow sticky traps were used to control pests, most farmers (84.7%) relied on chemical pesticides. Young and educated farmers were interested in non-chemical pest management options compared to their counterparts. Farmers believed that intercultural operation like weeding and pruning could reduce insect pests in cashew orchards. [ABSTRACT FROM AUTHOR]

Shoshonitic rocks represent the transition between calcalkaline and alkaline rocks, often formed during the last stages of uplift in zones of continental collision. This study describes the characterization of Kyrdem granitoids of Shillong plateau, Meghalaya, North East India, as felsic shoshonites. The study also documents petrogenesis of the shoshonites and suggests significant magma mixing and crust–mantle melt interaction as prime mechanisms for parental magma evolution. Crustal melt has most probably been sourced from a metabasaltic middle crust, while the mantle source is represented by an enriched sub-continental lithospheric mantle, metasomatized by sediment melt, during an earlier subduction event. [ABSTRACT FROM AUTHOR]

A systematic review and meta-analysis were conducted to investigate the SARS-CoV-2 viral load in human saliva and compared it with the loads in oropharyngeal swabs, nasopharyngeal swabs, and sputum. In addition, the salivary viral loads of symptomatic and asymptomatic COVID-19 patients were compared. Searches were conducted using four electronic databases: PubMed, Embase, Scopus, and Web of Science, for studies published on SARS-CoV-2 loads expressed by CT values or copies/mL RNA. Three reviewers evaluated the included studies to confirm eligibility and assessed the risk of bias. A total of 37 studies were included. Mean CT values in saliva ranged from 21.5 to 39.6 and mean copies/mL RNA ranged from 1.91 × 101 to 6.98 × 1011. Meta-analysis revealed no significant differences in SARS-CoV-2 load in saliva compared to oropharyngeal swabs, nasopharyngeal swabs, and sputum. In addition, no significant differences were observed in the salivary viral load of symptomatic and asymptomatic COVID-19 patients. We conclude that saliva specimen can be used as an alternative for SARS-CoV-2 detection in oropharyngeal swabs, nasopharyngeal swabs, and sputum. [ABSTRACT FROM AUTHOR]

The unfolding of MVDC (Medium Voltage DC) systems has the prospects to enable the incorporation of power electronic converters with higher power density and reliability. A tool with an integrated design approach is required to minimise the overall system volume by identifying optimal components. In this paper, a component-level early-stage design tool has been developed to attain the minimum achievable volume and failure rate for MVDC power converters. The developed tool optimises the choice of semiconductor switching devices, required heatsink, and other passive components (including dc-link filters and inductors) to minimise failure rate and overall converter volume. The optimisation algorithm employs the non-dominated sorting genetic algorithm (NSGA-II) to evaluate designs based on developed fitness functions. The design tool demonstrates the trade-off when evaluating multiple converter topologies and helps make an informed decision. A comparative study between two converter topologies shows the outcomes in terms of targeted metrics (volume and failure rate). This tool is expected to benefit early-stage design to perform trade-off studies among power electronic converter topologies based on key metrics like volume and failure rate. [ABSTRACT FROM AUTHOR]

A commercially viable metal–dielectric–metal configured triple-band metamaterial absorber is offered in this paper. It is an aggregation of four compact symmetric circles, with a swastika-shaped metal structure, which are bonded by two split-ring resonators (SRRs). Copper (annealed) of electrical conductivity 5.8 × 107 Sm−1 is used for the ground plate and resonator portion of the top layer and an FR 4 dielectric of permittivity 4.3 is used as a substrate. The structural parameters of the unit cell were determined by a trial and error method. FIT-based 3D simulation software (CST microwave studio, 2019 version was used to characterize the proposed perfect metamaterial absorber (PMA). Three resonance peaks were observed at frequencies 3.03, 5.83 and 7.23 GHz with an absorbance of 99.84%, 99.03% and 98.26%, respectively. The numerical result has been validated by some authentic validation methods. Finally, a microwave network analyzer (PNA) of Agilent N5227 with waveguide ports were deployed for measurement. The simulation and experimental results show better harmony. The proposed PMA has a unique design and a small dimension with higher absorption compared to other contemporary studies. This special type of polarization, insensitive S- and C-band PMA, is designed for a telecommunication system via full-time raw satellite and radar feeds. [ABSTRACT FROM AUTHOR]

Metamaterial analysis for microwave frequencies is a common practice. However, adopting a multi-layered design is unique in the concept of miniaturisation, thus requiring extensive research for optimal performance. This study focuses on a multi-layered symmetric metamaterial design for C- and X-band applications. All simulation analyses were performed analytically using Computer Simulation Technology Studio Suite 2019. The performances of the proposed metamaterial design were analysed through several parametric studies. Based on the observation, the proposed metamaterial unit cell design manifested resonant frequencies at 7.63 GHz (C-band) and 9.56 GHz (X-band). Moreover, the analysis of effective medium parameters was also included in this study. High-Frequency Simulation 15.0 and Advanced Design System 2020 software validated the transmission coefficient results. Simultaneously, the proposed multi-layered metamaterial design with Rogers RO3006 substrate material exhibited a unique transmission coefficient using double, triple, and quadruple layers. The two resonant frequencies in the unit cell design were successfully increased to three in the double-layer structure at 6.34 GHz (C-band), 8.46 and 11.13 GHz (X-band). The proposed unit cell design was arranged in an array structure to analyse the performance changes in the transmission coefficient. Overall, the proposed metamaterial design accomplished the miniaturisation concept by arranging unit cells in a multi-layer structure and possesses unique properties such as a highly effective medium ratio and left-handed characteristics. [ABSTRACT FROM AUTHOR]

This study assesses quad-band metamaterial perfect absorbers (MPAs) based on a double X-shaped ring resonator for electromagnetic interference (EMI) shielding applications. EMI shielding applications are primarily concerned with the shielding effectiveness values where the resonance is uniformly or non-sequentially modulated depending on the reflection and absorption behaviour. The proposed unit cell consists of double X-shaped ring resonators, a dielectric substrate of Rogers RT5870 with 1.575 mm thickness, a sensing layer, and a copper ground layer. The presented MPA yielded maximum absorptions of 99.9%, 99.9%, 99.9%, and 99.8% at 4.87 GHz, 7.49 GHz, 11.78 GHz, and 13.09 GHz resonance frequencies for the transverse electric (TE) and transverse magnetic (TM) modes at a normal polarisation angle. When the electromagnetic (EM) field with the surface current flow was investigated, the mechanisms of quad-band perfect absorption were revealed. Moreover, the theoretical analysis indicated that the MPA provides a shielding effectiveness of more than 45 dB across all bands in both TE and TM modes. An analogous circuit demonstrated that it could yield superior MPAs using the ADS software. Based on the findings, the suggested MPA is anticipated to be valuable for EMI shielding purposes. [ABSTRACT FROM AUTHOR]

Objectives: Sickle cell anemia is the most common genetic disorder that affects hemoglobin. People with this disorder have atypical hemoglobin molecules called hemoglobin S, which can distort red blood cells into a sickle, or crescent shape. Sickle cell disease is an increasing global health problem. Estimates suggest that every year approximately 300,000 infants are born with sickle cell anemia, which is defined as an autosomal recessive disorder. The objective of this study is to show that the newborn screening of sickle cell anemia is possible through the procedure by utilizing the cord blood. Materials and Methods: A total number of 30 samples were collected from individual mother and cord blood. DNA was extracted from 13 mothers and 13 fetal cord blood samples and used these DNA to detect sickle cell anemia using wild type and mutant type primer. Results: ß hemoglobin gene was amplified by wild type and mutant type primer using PCR and revealed 517bp and 267bp length DNA fragments, respectively. In this study, it was observed that only one homozygous (Hb S/S) mother and newborn found. Most of the mothers and newborns were carrier of sickle cell anemia which means they were heterozygous (Hb A/S). Two pairs were found where mother was carrier, but newborns were healthy (Hb A/A). Conclusions: With this study, it can come to the point that the newborn screening of sickle cell anemia is possible through the procedure by utilizing the cord blood that is wasted every time during delivery. By maternal screening in this way, the probability of disease transmission can also be checked earlier. For Bangladesh, this approach can be an effective tool for screening sickle cell anemia. [ABSTRACT FROM AUTHOR]

Flying insects routinely demonstrate coordinated flight in crowded assemblies despite strict communication and processing constraints. This study experimentally records multiple flying insects tracking a moving visual stimulus. System identification techniques are used to robustly identify the tracking dynamics, including a visuomotor delay. The population delay distributions are quantified for solo and group behaviors. An interconnected visual swarm model incorporating heterogeneous delays is developed, and bifurcation analysis and swarm simulation are applied to assess swarm stability under the delays. The experiment recorded 450 insect trajectories and quantified visual tracking delay variation. Solitary tasks showed a 30ms average delay and standard deviation of 50ms, while group behaviors show a 15ms average and 8ms standard deviation. Analysis and simulation indicate that the delay adjustments during group flight support swarm formation and center stability, and are robust to measurement noise. These results quantify the role of visuomotor delay heterogeneity in flying insects and their role in supporting swarm cohesion through implicit communication. [ABSTRACT FROM AUTHOR]

Building a reliable and precise model for disease classification and identifying abnormal sites can provide physicians assistance in their decision-making process. Deep learning based image analysis is a promising technique for enriching the decision making process, and accordingly strengthening patient care. This work presents a convolutional attention mapping deep learning model, Cardio-XAttentionNet, to classify and localize cardiomegaly effectively. We revisit the global average pooling (GAP) system and add a weighting term to develop a light and effective Attention Mapping Mechanism (AMM). The model enables the classification of cardiomegaly from chest X-rays through image-level classification and pixel-level localization only from image-level labels. We leverage some of the advanced ConvNet architectures as a backbone-model of the proposed attention mapping network to build Cardio-XAttentionNet. The proposed model is trained on ChestX-Ray14, which is a publicly accessible chest X-ray dataset. The best single model achieves an overall precision, recall, F-1 measure and area under curve (AUC) scores of 0.87, 0.85, 0.86 and 0.89, respectively, for the classification of the cardiomegaly. The results also demonstrate that the Cardio-XAttentionNet model well captures the cardiomegaly class information at image-level as well as localization at pixel-level on chest x-rays. A comparative analysis between the proposed AMM and existing GAP based models shows that the proposed model achieves a state-of-the-art performance on this dataset for cardiomegaly detection using a single model. [ABSTRACT FROM AUTHOR]

Proteins are large biomolecules in the form of polypeptide chains consisting of amino acid (AA) residues. Ultraviolet–visible absorption spectroscopy and continuous wave (CW) z-scan of bovine serum albumin (BSA) and some of its constituent AAs were examined to deduce the relationship between the optical properties of this protein molecule and its constituents. From the analysis of their optical spectra, the absorption at 278 nm by BSA is found to be the outcome of the cumulative effects of the absorptions by constituent aromatic AA residues, cysteine disulfide bonds, and methionine. Similarly, the closed aperture CW z-scan of BSA and those of the constituent AAs at 74–106 mW incident optical power at 655 nm indicate that thermally generated third-order optical effects arise in BSA and its aromatic AA residues due to multiphoton absorptions. The nonlinear optical (NLO) responses of BSA and those of the AA residues are compared in terms of their molar phase shift per unit power, which indicate a possible relationship between the NLO property of BSA and its AA residues. [ABSTRACT FROM AUTHOR]

We created an ultra-thin, triple-band incident angle-insensitive perfect metamaterial absorber (MMA) with a metallic patch and a continuous metal ground isolated by a central dielectric substrate. The top metallic patch, placed across the edges of the 0.58 mm thickness Rogers RO4003C (lossy) substrate, forms the bulk of the projected absorber's ultra-thin layer. Nonetheless, absorption is exceedingly strong, covering C-band, X-band and K-band and reaching levels of 97.8%, 99.9%, and 99.9%, respectively, under normal and even oblique (0° to 45°) incident conditions. In chosen ranges of frequency of 6.24, 10.608, and 18.624 GHz for both TM and TE mode, the displayed Q-factors were 62.4, 17.68, and 26.61, respectively. We correspondingly calculated the RAB (relative absorption bandwidth) to evaluate absorption performance. An equivalent circuit proved its performance capabilities, indicating that it would produce a high-quality MMA from ADS software. Furthermore, the absorber's performance has been verified in free space on a sample being tested using a different array of unit cells. Moreover, the proposed structures with HFSS simulators to display the MMA's absolute absorption at each absorption peak are somewhat inconsistent with the results of the CST simulator. Because of its superior performance, the ultra-thin absorber is suited for a wide range of applications, including satellite applications such as radar systems, stealth technology, imaging, and electromagnetic interference reduction. [ABSTRACT FROM AUTHOR]

A split-ring resonator (SRR)-based power tiller wheel-shaped quad-band ℇ-negative metamaterial is presented in this research article. This is a new compact metamaterial with a high effective medium ratio (EMR) designed with three modified octagonal split-ring resonators (OSRRs). The electrical dimension of the proposed metamaterial (MM) unit cell is 0.086λ × 0.086λ, where λ is the wavelength calculated at the lowest resonance frequency of 2.35 GHz. Dielectric RT6002 materials of standard thickness (1.524 mm) were used as a substrate. Computer simulation technology (CST) Microwave Studio simulator shows four resonance peaks at 2.35, 7.72, 9.23 and 10.68 GHz with magnitudes of −43.23 dB −31.05 dB, −44.58 dB and −31.71 dB, respectively. Moreover, negative permittivity (ℇ) is observed in the frequency ranges of 2.35–3.01 GHz, 7.72–8.03 GHz, 9.23–10.02 GHz and 10.69–11.81 GHz. Additionally, a negative refractive index is observed in the frequency ranges of 2.36–3.19 GHz, 7.74–7.87 GHz, 9.26–10.33 GHz and 10.70–11.81 GHz, with near-zero permeability noted in the environments of these frequency ranges. The medium effectiveness indicator effective medium ratio (EMR) of the proposed MM is an estimated 11.61 at the lowest frequency of 2.35 GHz. The simulated results of the anticipated structure are validated by authentication processes such as array orientation, HFSS and ADS for an equivalent electrical circuit model. Given its high EMR and compactness in dimensions, the presented metamaterial can be used in S-, C- and X-band wireless communication applications. [ABSTRACT FROM AUTHOR]

This work focused on the novel and compact 1-bit symmetrical coding-based metamaterial for radar cross section reduction in terahertz frequencies. A couple of coding particles were constructed to impersonate the elements '0′ and '1′, which have phase differences of 180°. All the analytical simulations were performed by adopting Computer Simulation Technology Microwave Studio 2019 software. Moreover, the transmission coefficient of the element '1′ was examined as well by adopting similar software and validated by a high-frequency structure simulator. Meanwhile, the frequency range from 0 to 3 THz was set in this work. The phase response properties of each element were examined before constructing various coding metamaterial designs in smaller and bigger lattices. The proposed unit cells exhibit phase responses at 0.84 THz and 1.54 THz, respectively. Meanwhile, the analysis of various coding sequences was carried out and they manifest interesting monostatic and bistatic radar cross section (RCS) reduction performances. The Coding Sequence 2 manifests the best bistatic RCS reduction values in smaller lattices, which reduced from −69.8 dBm2 to −65.5 dBm2 at 1.54 THz. On the other hand, the monostatic RCS values for all lattices have an inclined line until they reach a frequency of 1.0 THz from more than −60 dBm2. However, from the 1.0 THz to 3.0 THz frequency range the RCS values have moderate discrepancies among the horizontal line for each lattice. Furthermore, two parametric studies were performed to examine the RCS reduction behaviour, for instance, multi-layer structures and as well tilt positioning of the proposed coding metamaterial. Overall it indicates that the integration of coding-based metamaterial successfully reduced the RCS values. [ABSTRACT FROM AUTHOR]

Persons with COVID-19-like illnesses are advised to stay home to reduce the spread of SARS-CoV-2. We assessed relationships between telework experience and COVID-19 illness with work attendance when ill. Adults experiencing fever, cough, or loss of taste or smell who sought healthcare or COVID-19 testing in the United States during March-November 2020 were enrolled. Adults with telework experience before illness were more likely to work at all (onsite or remotely) during illness (87.8%) than those with no telework experience (49.9%) (adjusted odds ratio 5.48, 95% CI 3.40-8.83). COVID-19 case-patients were less likely to work onsite (22.1%) than were persons with other acute respiratory illnesses (37.3%) (adjusted odds ratio 0.36, 95% CI 0.24-0.53). Among COVID-19 case-patients with telework experience, only 6.5% worked onsite during illness. Telework experience before illness gave mildly ill workers the option to work and improved compliance with public health recommendations to stay home during illness. [ABSTRACT FROM AUTHOR]

Aerial swarm implementations often underperform their feedback design goals due to sensor noise, modeling errors, and external disturbances, each of which can often be mitigated by including robustness in the design approach. At the same time, gain modulation has been measured in numerous insect flight examples involving relative position regulation and tracking. Gains are often lower than what initially appears optimal, which is not fully explained by existing hypotheses. This article analyzes the robustness of a visual feedback control system modeling insect flight feedback paths by using optic flow to regulate an agent's motion relative to its neighbors. This study considers the system's robustness to sensor noise and configuration deviations, which appear as a nonlinearity in the observation equation often neglected in linear feedback. The analysis indicates robust performance can be attained by a static gain H∞$$ {H}_{\infty } $$ controller by appropriate choice of gain. Experimental results using an optic flow swarm implementation in robotic systems are used to quantify the actual system performance for static gain controllers. Performance is compared when the system responds to ideal optic flow (no sensor noise) and to camera‐based optic flow swarm implementation (sensor noise and configuration uncertainty). [Correction added on 10 November 2022, after first online publication: the underline in the word 'compared' of the preceding sentence has been removed in this version.] The analysis suggests neural gain modulation in insect feedback paths may support robust group motion stabilization. [ABSTRACT FROM AUTHOR]

Introduction: Chronic kidney disease (CKD) is characterized by a progressive loss of renal function that often leads to end-stage renal disease (ESRD), high risk for cardiovascular disease, and high mortality. Diabetes mellitus is a growing epidemic and is the most common cause of chronic kidney disease (CKD) and kidney failure. Diabetic nephropathy affects approximately 20-40 % of individuals who have diabetes, making it one of the most common complications related to diabetes. Screening for diabetic nephropathy along with early intervention is fundamental to delaying its progression in conjunction with providing proper glycemic control. The kidneys play a vital role in the excretion of waste products and toxins such as urea, creatinine and uric acid, regulation of extracellular fluid volume, serum osmolality and electrolyte concentrations, as well as the production of hormones like erythropoietin and 1,25 dihydroxy vitamin D and renin. Material and Methods: This is a prospective and observational study was conducted in the Department of Biochemistry at Tertiary care Teaching Hospital over a period of 1 year. Either Gender aged between 18 and 70 years. The study participants were signed written informed consent before the start of data collection. The study participants were selected based on a convenient sampling technique and total of 120 study participants were included. Subjects suffered from an acute infection and critically sick individuals were excluded from the study. Results: There was a significant difference between case when compared to Control in Male and female. There was a significant difference in case group in FBS, HbA1c, Urea and S. Creatinine when compared to control group and no significant difference between both groups in SBP and DBP. Conclusion: The present study it can be inferred that serum urea and creatinine levels were significantly higher in CKD subjects then control subjects. Increased amount of urea and creatinine levels were seen only in CKD subjects and no difference was seen in controls. Thus, it can be recommend that urea and creatinine values can be used for screening of renal status in CKD subjects. [ABSTRACT FROM AUTHOR]

Reproductive success for crustaceans depends on the transition from juvenile to adult, which can be estimated by analysing relative growth. To this end, the present study focused on the relative growth of appendix masculina length (AML), hatchery chamber width (HCW), body length (BL) and body weight (BW) in relation to carapace length (CL) of Macrobrachium villosimanus to estimate the morphological sexual maturity using the least squares method. Data for each relationship were repeatedly partitioned into two size‐delimited subsets (juvenile and adult stages), considering a CL value as a hypothesized transition point. Analysis of the residuals sum of squares indicated two separate linear regressions fit the data better than a single linear regression. The study results indicated a discontinuity in allometry at 17.9 mm CL for CL versus AML, and at 15.6 mm CL for CL versus HCW relationships. These observed transition points could be associated with morphological sexual maturity of M. villosimanus. The BL and BW growth rate in relation to CL significantly decreased in males, but increased in females after reaching the morphological sexual maturity, demonstrating the existence of dimorphic growth. The increased growth rate after reaching sexual maturity in females probably corresponds to more space for the eggs and subsequent increased fertility. Accordingly, the present study indicated the secondary sexual characters (e.g. AML and HCW) play roles in attaining the morphological sexual maturity necessary for reproductive success and for ensuring the life cycle of this species. [ABSTRACT FROM AUTHOR]

Ramie fiber reinforced thermoplastic and thermoset polymer composites Ramie is the toughest bast fiber that yielded its fiber from the bark of the canes, which supplies exceptional raw material for blending with natural and synthetic fibers with higher luster, tenacity, brightness, and resistance to light, heat, alkali, and acid (Kiruthika [40]; Rehman et al. [74]). Hemp fiber reinforced thermoplastic and thermoset polymer composites Hemp fiber is another branch of bast fibers that are extremely used in the development of bio-based composites to prevail over the use of synthetic-based composite materials in the diversified application areas (Aisyah et al. [1]; Dixit et al. [18]). Kenaf fiber reinforced thermoplastic and thermoset polymer composites Kenaf fibers can widely be used in the fabrication of composite materials due to their higher mechanical properties. Digital images of different bast fibers: (a-a1) flax fibers, (b-b1) hemp fibers, (c-c1) jute fibers, (d-d1) ramie fibers, and (e-e1) kenaf fibers. Keywords: Natural bast fibers; thermoplastic and thermosetting polymers; classification; biodegradability; eco-friendly and sustainable composites; properties and applications EN Natural bast fibers thermoplastic and thermosetting polymers classification biodegradability eco-friendly and sustainable composites properties and applications 8006 8021 16 11/21/22 20221220 NES 221220 Introduction Composites are generally known as materials having multifunctional physical and chemical properties, which are manufactured by using two or more individual materials of different characteristics (Mastura et al. [49]; Sahu and Gupta [78]). [Extracted from the article]

The present study aims at investigating the vegetation in different sites of Chattogram metropolitan area following appropriate techniques. In order to enumerate the distribution of species, several diversity indices including Shannon-Winer Index, Pielou's Evenness and Simpson's Index were employed. A total of 645 species belonging to 414 genera under 120 families were documented from the studied area for the first time. Of these, 37 species (5.73%) are pteridophytes, 607 species (94.11%) are angiosperms and single representation of gymnosperm (0.16%). Among the recorded species, 384 are medicinal species belonging to 277 genera under 93 families. Bacopa monnieri is a dominant species in the forest area with some co-dominant species like Eichhornia crassipes, Centella asiatica, etc. Moreover, this study provides potential sources to the environmental planners, herbalists, ecologists, taxonomists, ethnobotanists, pharmacists, phytochemists and local administration that would help to plan for future green infrastructure and maintain ecosystem function providing long-term benefits for the city dwellers. [ABSTRACT FROM AUTHOR]

The Naga Hills Ophiolite (NHO) of Late Jurassic to Eocene age is one of the well‐exposed domains of Tethyan ophiolites, located in the northern margin of the Indo‐Myanmar Orogenic Belt, north‐east India. It is composed of suites of tectonite peridotite and cumulative ultramafic, mafic intrusive‐extrusive rocks, felsic intrusive, radiolarian, and marine pelagic sediments. The mafic intrusives of the NHO exhibit rhythmic to cryptic layering and isotropic in nature. Based on their mineralogy, the mafic intrusives are identified as gabbro, gabbronorite, hornblende gabbro, and olivine gabbro. The gabbros are adcumulate and mesocumulate and essentially composed of plagioclase feldspar, clinopyroxene, orthopyroxene, hornblende, with minor olivine, serpentine, chlorite, and magnetite. These mafic intrusive rocks show affinity to tholeiitic parental magma and fractionated trends in the multi‐elemental diagram, with negative anomalies at Zr, P, Ce and positive anomalies at Sr, Nb, and Ti suggesting that the magmatism was influenced by subduction zone components. The majority of the samples represent light rare earth elements (LREE) depletion (LaN/SmN = 0.28–0.86), except two samples that display LREE enrichment (LaN/SmN = 2.11–3.03), with negligible negative Eu anomaly. Petrogenetic modelling suggests 5%–20% partial melting of a depleted mid‐ocean ridge basalt‐type mantle source, within the spinel lherzolite stability field, as well as low degree partial melting (<10%) of an enriched mantle source probably metasomatized by sediment‐melt from a subducted slab. Therefore, based on mineralogical and geochemical data, we propose that the mafic intrusive of the NHO were generated in the intra‐oceanic arc system within the Neotethys Ocean with the active participation of possible wet basaltic melt from spinel‐lherzolite source‐mantle, subsequently modified by melts derived from sediments in a subduction zone. [ABSTRACT FROM AUTHOR]

A three parameter novel hyperelastic strain energy function is introduced in this paper for soft and rubber-like materials. The function integrates a non-separable exponential component with a single term Ogden-type polynomial-like function, resulting in an exponential-polynomial based strain energy function. This helps in capturing both small and large deformation (stretch) behaviours of hyperelastic materials. The structure of the model is simple and validated against several experimental datasets including rubbers, hydrogel, and soft tissues. The model is reported to capture key material behaviors, including strain stiffening and various deformation paths. Through comparative studies with well-known models like the Ogden (six parameters) and Yeoh (three parameters), the model's effectiveness is established. Furthermore, the model successfully addresses pressure-inflation instability in thin spherical balloons. It's applicability extends to biological materials, as evidenced by its effectiveness in characterizing porcine brain tissue and a monkey's bladder. [Display omitted] • A three parameter strain energy function for soft and rubber-like materials has been developed. • Combined an exponential component with an Ogden-type polynomial term. • Experimental data of rubbers, hydrogel, and soft tissue are used to validate the model. • The model effectively addresses pressure-inflation instability in thin spherical balloons. • Advantages of the model are illustrated through comparisons with Ogden and Yeoh models. [ABSTRACT FROM AUTHOR]

• A microstructural analysis demonstrates that the grain growth of the samples is influenced by the amount of Bi 2 O 3 addition resulting an increase of the average grain size from 1.12 (for x = 0.0 wt%) to 2.74 μ m (for x = 0.6 wt%). • The magnetic hysteresis measurement shows that the saturation magnetization increases from 72.1 (for x = 0.0 wt%) to 77.6 emu/g (for x = 0.6 wt% Bi 2 O 3). However, it declined at x = 0.8 wt%, which may be ascribed to the dilution effect. • The complex magnetic permeability measurement shows that an enhancement of the initial permeability is clearly observed with the addition of Bi 2 O 3 content. • The RQF is also shown a larger value for x = 0.6 wt% Bi 2 O 3 content, which is good agreement along with the microstructural feature. Influence of Bi 2 O 3 addition on the microstructure and magnetic properties of Li-Cu-Mg-Zn ferrites having the compositions Li 0.25 Cu 0.10 Mg 0.10 Zn 0.30 Fe 2.25 O 4 + xBi 2 O 3 (where x = 0.0, 0.3, 0.4, 0.6 and 0.8 wt%) have been reported in this study. The structural property has been studied with the X-ray diffraction technique, which reveals that all the samples have shown the cubic spinel phase without any impurity peak. A microstructural analysis demonstrates that the grain growth of the samples is influenced by the amount of Bi 2 O 3 addition resulting an increase of the average grain size from 0.84 (for x = 0.0 wt%) to 2.47 µ m (for x = 0.6 wt%). The development of the grain size could be attributed to the densification of sample due to the formation of the liquid phase of Bi 2 O 3 in the sintering process. The magnetic hysteresis measurement shows that the saturation magnetization increases from 72.1 (for x = 0.0 wt%) to 77.6 emu/g (for x = 0.6 wt% Bi 2 O 3). However, it declined at x = 0.8 wt%, which may be ascribed to the dilution effect. The complex magnetic permeability measurement shows that an enhancement of the initial permeability is clearly observed with the addition of Bi 2 O 3 content. It is inferred that a correlation has been found between the grain growth and the magnetic properties of the investigated samples. Fourier transforms infrared absorption reveals that the frequency band appears in the high frequency (539–555 cm−1) range which can be attributed to the stretching vibrations at the tetrahedral site. The band appearing in the low frequency (359–373 cm−1) range is for the octahedral site, which is due to bending vibration. The elastic constants such as bulk modulus, Young's modulus, rigidity modulus, Poisson's ratio and Pugh's ratio have been calculated for all the studied samples. It shows that all synthesized samples are in ductile nature. [ABSTRACT FROM AUTHOR]

Olfactory stimulation with mastic resin, derived from the Pistacia lentiscus tree, demonstrated a bona fide sialagogic effect in healthy volunteers [1]. Its main volatile compound, α-pinene, also showed this effect. The current study aimed to validate the effect of mastic resin volatiles in chronic dry mouth patients with confirmed decreased saliva secretion. 41 chronic dry mouth patients with decreased unstimulated saliva secretion (<0.25 mL/min) were exposed to mastic resin volatiles as part of the diagnostic routine at the Saliva Clinic of Academic Centre for Dentistry Amsterdam. During their visit, dry-mouth questionnaires were conducted and samples of unstimulated whole saliva, chew-stimulated saliva, acid-stimulated saliva and mastic resin stimulated saliva were collected. Saliva flow rate, spinnbarkeit, pH, ion composition, MUC5B and MUC7 levels in all samples were analyzed. Salivary flow rates increased by all stimuli when compared to the baseline unstimulated saliva (P <0.001). During olfactory mastic resin stimulation, the salivary spinnbarkeit (P <0.001) and sodium concentration (P <0.01) were increased compared to unstimulated saliva. MUC5B and MUC7 levels were increased during olfactory mastic resin stimulation compared to chew-stimulated saliva (P =0.016 and P <0.001, respectively). Spinnbarkeit correlated positively with MUC5B (R=0.399, P =0.002) and MUC7 levels (R=0.375, P =0.004). Results of dry-mouth questionnaires indicated reduced posterior palate dryness shortly after olfactory mastic resin stimulation (P= 0.04). Olfactory mastic resin stimulation increased mucous saliva secretion and reduced posterior palate dryness in a group of chronic dry mouth patients. These findings, validated in patients, underscore mastic resin scent as a beneficial and non-invasive sialagogic treatment for clinical applications. [Display omitted] [ABSTRACT FROM AUTHOR]

Insects are model systems for swarming robotic agents, yet engineered descriptions do not fully explain the mechanisms by which they provide onboard sensing and feedback to support such motions; in particular, the exact value and population distribution of visuomotor processing delays are not yet quantified, nor the effect of such delays on a visually-interconnected swarm. This study measures untethered insects performing a solo in-flight visual tracking task and applies system identification techniques to build an experimentally-consistent model of the visual tracking behaviors, and then integrates the measured experimental delay and its variation into a visually interconnected swarm model to develop theoretical and simulated solutions and stability limits. The experimental techniques include the development of a moving visual stimulus and real-time multi camera based tracking system called VISIONS (Visual Input System Identification from Outputs of Naturalistic Swarms) providing the capability to recognize and simultaneously track both a visual stimulus (input) and an insect at a frame rate of 60-120 Hz. A frequency domain analysis of honeybee tracking trajectories is conducted via fast Fourier and Chirp Z transforms, identifying a coherent linear region and its model structure. The model output is compared in time and frequency domain simulations. The experimentally measured delays are then related to probability density functions, and both the measured delays and their distribution are incorporated as inter-agent interaction delays in a second order swarming dynamics model. Linear stability and bifurcation analysis on the long range asymptotic behavior is used to identify delay distributions leading to a family of solutions with stable and unstable swarm center of mass (barycenter) locations. Numerical simulations are used to verify these results with both continuous and measured distributions. The results of this experiment quantify a model structure and temporal lag (transport delay) in the closed loop dynamics, and show that this delay varies across 50 individuals from 5-110ms, with an average delay of 22ms and a standard deviation of 40ms. When analyzed within the swarm model, the measured delays support a diversity of solutions and indicate an unstable barycenter. [ABSTRACT FROM AUTHOR]

In this article, we present the use of a metamaterial-incorporated microwave-based sensor with a single port network for material characterization. The proposed sensor consists of a microstrip patch layer enclosed with a dual-square-shaped metamaterial split-ring. This structure has the dimensions of 20 × 20 × 1.524 mm3 and a copper metallic layer is placed on a Rogers RT 6002 with a partial back layer as a ground. Two resonant frequencies are exhibited for applied electromagnetic interaction using a transmission line. The dual split rings increase the compactness and accumulation of the electromagnetic field on the surface of the conducting layer to improve the sensitivity of the sensor. The numerical studies are carried out using a CST high-frequency microwave simulator. The validation of the proposed sensor is performed with an equivalent circuit model in ADS and numerical high-frequency simulator HFSS. The material under test placed on the proposed sensor shows good agreement with the frequency deviation for different permittivity variations. Different substrates are analyzed as a host medium of the sensor for parametric analysis. [ABSTRACT FROM AUTHOR]

This study aimed to investigate the compact 1-bit coding metamaterial design with various conventional and cuboid shapes by analysing the bistatic scattering patterns as well as the monostatic radar cross-section for microwave applications. The construction of this metamaterial design depends on binary elements. For example, 1-bit coding metamaterial comprises two kinds of unit cell to mimic both coding particles such as '0' and '1' with 0° and 180° phase responses. This study adopted a 1 mm × 1 mm of epoxy resin fibre (FR-4) substrate material, which possesses a dielectric constant of 4.3 and tangent loss of 0.025, to construct both elements for the 1-bit coding metamaterial. All simulations were performed using the well-known Computer Simulation Technology (CST) software. The elements were selected via a trial-and-error method based on the phase response properties of the designs. On the other hand, the phase response properties from CST software were validated through the comparison of the phase response properties of both elements with the analytical data from HFSS software. Clear closure was obtained from these findings, and it was concluded that the proposed conventional coding metamaterial manifested the lowest RCS values with an increasing number of lattices. However, the cuboid-shaped design with 20 lattices demonstrated an optimised bistatic scattering pattern of −8.49 dBm2. Additionally, the monostatic RCS values were successfully reduced within the 12 to 18 GHz frequency range with −30 to −10 dBm2 values. In short, the introduced designs were suitable for the proposed application field, and this unique phenomenon is described as the novelty of this study. [ABSTRACT FROM AUTHOR]

Introduction & background: Prolonged (duration >7 to 13 days) diarrhea (ProD) in under-five children is a universal health problem including Bangladesh. Data on epidemiology and associated or risk factors of ProD are limited, particularly in Bangladesh where a high burden of ProD is reported. This study intended to assess the case load of ProD and its associated or risk factors compared to acute diarrhea (AD, duration ≤7 days). Methods: We analyzed the data collected between 1996–2014 from a hospital-based Diarrheal-Disease-Surveillance-System (DDSS) in the 'Dhaka Hospital' of International Centre for Diarrhoeal Diseases, Bangladesh (icddr,b). The DDSS enrolled a 2% systematic sample, regardless of age, sex, and diarrhea severity. The data included information on socio-demographic factors, environmental history, clinical characteristics, nutritional status, and diarrhea-pathogens. After cleaning of data, relevant information of 21,566 under-five children were available who reported with ≤13 days diarrhea (including AD and ProD), and their data were analyzed. Variables found significantly associated with ProD compared to AD in bi-variate analysis were used in logistic regression model after checking the multicollinearity between independent variables. Results: The mean±SD age of the children was 14.9±11.7 months and 40.4% were female; 7.6% had ProD and 92.4% had AD. Age <12 months, mucoid- or bloody-stool, warmer months (April-September), drug used at home before seeking care from hospital, and history of diarrhea within last one month were found associated with ProD (p<0.05); however, rotavirus infection was less common in children with ProD (p<0.05). ProD children more often needed inpatient admission than AD children (14.4 vs. 6.3, p<0.001). Case fatality rate of ProD vs. AD was 0.3% (n = 5) vs. 0.1% (n- = 22) respectively (p = 0.051). Conclusion: A considerable proportion (7.6%) of under-five children reporting to icddr,b hospital suffered from ProD. Understanding the above-mentioned associated or risk factors is likely to help policy makers formulating appropriate strategies for alleviating the burden and effectively managing ProD in under-five children. [ABSTRACT FROM AUTHOR]

The strong localization of the electric and magnetic fields in metamaterial-based structures has attracted a new era of radiation fields in the microwave range. In this research work, we represent a double split ring enclosed nested meander-line-shaped metamaterial resonator with a high effective medium ratio layered on a dielectric substrate to enhance the sensitivity for the material characterization. Tailoring a metallic design and periodical arrangement of the split ring resonator in a subwavelength range introduced field enhancement and strong localization of the electromagnetic field. The design methodology is carried out through the optimization technique with different geometric configurations to increase the compactness of the design. The CST microwave studio is utilized for the extraction of the scattering computational value within the defined boundary condition. The effective parameters from the reflection and transmission coefficient are taken into account to observe the radiation characteristics for the interaction with the applied electromagnetic spectrum. The proposed metamaterial-based sensor exhibits high sensitivity for different dielectric materials with low permittivity values. The numerical data of the frequency deviation for the different dielectric constants have shown good agreement using the linear regression analysis where the sensitivity is R2 = 0.9894 and the figure of merit is R2 = 0.9978. [ABSTRACT FROM AUTHOR]

The objective of this systematic review is to synthesize the relevant literature published after 2016 to ascertain the current landscape of science that relates mild traumatic brain injury (mTBI) to the onset of Alzheimer's disease and related dementias (ADRD) and identify areas of need for future research. We conducted database searches and retrieved articles that were published after 2016 that utilized cognitive assessments to understand the relationship between mTBI and ADRD. We identified eight relevant articles in the review process, four of which presented a significant relationship between mTBI and disease or cognitive impairment outcomes. The studies included in this systematic review underscore the need for future research investigating a possible causal relationship between mTBI and ADRDs given the high prevalence of mTBI among brain injury patients and the lack of literature specifically addressing this issue. Future research should standardize the definitions of mTBI, AD, and ADRDs to create reliable and reproducible results that more comprehensively capture the nuances of this relationship. [ABSTRACT FROM AUTHOR]