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Silicene, a zero-gap semi-metallic advanced material, has received much attention due to its extraordinary electronic and optical characteristics, which could be used in plasmonics nano-devices. This material presenting as a tunable material without degrading its high carrier mobility. By applying the rigorous numerical techniques, the optical and electrical properties of silicene at high terahertz frequencies are calculated here. Beneath the influence of environmental effects such as the Fermi level, temperature, and external electric field, on the optical conductivity and refractive index of silicene are investigated using the tight-binding model. The effect of Fermi level from zero to 1 eV, external electric field from zero to 2.5 eV, and temperature from 5 to 400 K are investigated on the optical properties of silicene. One of the interesting features of Silicene is its adjustable bandgap, which we are present here.

The steering of guided light in surface plasmon resonance (SPR) sensing platforms introduced more than eight decades ago from the first proposed optical sensor in 1983. However, sensing the environmental variation considering transverse modes is still require the attention from the scientist. Here, for the first time, by considering steering of guided light a high-performance SPR sensor base on Otto structure is proposed. By incorporating the graphene and white graphene in to a prism-waveguide configuration, we calculated the excitation of both TE(TM) modes as refractive index is changed from 1 to 1.04. to analysis of the structure finite-difference time-domain (FDTD) is applied. To benchmark of the structure performance parameters including sensitivity, figure of merit, polarization extinction ratio (PER), and insertion loss (IL) are calculated. Numerical results show that maximum sensitivity and figure of merit are obtained for TM modes of 1226 and 27 respectively. In such a case, graphene monolayer is applied. By considering coupling condition, at the μc = 0.4 eV, the maximum value of PER is 75 dB, and IL is 0.022 dB. Moreover, it is obtained that in all these conditions PER is higher than 8 dB, and IL is less than 0.04 dB.

Bolometer sensors are prominent and excellent choice in technology because they do not need cooling. The trade-off between high sensitivity, fast response time, and strong light absorption is a key important challenge in bolometer sensors. Here, the bolometric effect for a high resistance sensitivity plasmonic sensing of total and profile infusion of radiation is studied for the proposed bolometer sensor based on plasmonic multilayer structure at 26° C. In the present study, by generating strong coupling condition between incident wave and surface plasmon polaritons (SPPs), a very narrow absorption spectra with high figure of merit (FoM) is achieved. The analytical model and numerical simulation are fulfilled based on the transfer matrix method (TMM) and 3-D finite-difference time-domain (FDTD), respectively. The narrow absorption spectra that generate by strong coupling with SPPs heats the silver thin film that leads to variation in temperature and supports TE surface mode. This temperature change rectifies the resistance of the metal thin film by the bolometric effect. So, optical characteristics of the proposed metasurface bolometer sensor, including quality factor (Q), sensitivity, and figure of merit (FoM) are calculated that Max sensitivity, FoM, and Q are 17.2 RIU-1, 530 and 434.5, respectively. Finally, we analytically simulate the temperature coefficient of resistance (TCR) in terms of wavelength and refractive index of analyte (na) that this resistance change can be monitored by an external electric model. The proposed plasmonic multilayer configuration is a very compact footprint structure that achieved high resistance sensitivity and FoM in comparison with any previous reports. This proposed thermal, optical, and electric plasmonic metasurface bolometer sensor can be used in different applications such as biophysics, biology, and environmental science.

The development of devices for communication networks to transmit information has become an active and growing field of research. Multiplexer/demultiplexer (M/D) is one of the basic devices in this field. In this paper, an M/D design is introduced based on the surface plasmon resonance in optical ring resonators. The number of inputs and outputs of M/D is 3 × 1 and 1 × 3, respectively. All parameters of the structure, including radius and width of ring resonators and waveguides, have been evaluated to obtain the optimal response. Also, we used the nonlinear gold property to expand the range of M/D performance and simulated the results for intensities less than 100 MW/cm2. Selectivity in the number of inputs and outputs, controllability using several parameters, all optically, selectivity in operation frequency, nanoscale size, reconfigurability, and integrated capability are the features of this design. In our simulation, we consider transmission and reflection of light in each port based on the finite difference time domain for evaluation of results.

Detection of low-index materials such as aerogels and also detection of refractive index variations in these materials is still a challenging task. Here, a high figure of merit (FOM) sensor based on plasmon-induced transparency (PIT) is proposed for the detection of aerogel refractive index changes. In the proposed PIT sensor, the transparency window in an opaque region arises from the coupling between surface plasmon polariton (SPP) mode and planar waveguide mode. By comprising sub-wavelength grating (SWG) in the planar waveguide region, the maximum of the electric field of waveguide occurs in a low index media. This facilitates detection of the aerogels when they are used as the low index material (sensing material). Application of the subwavelength grating waveguide also improves the sensitivity of the sensor by a factor of six compared to a conventional structure with a homogenous waveguide. The proposed structure has a quality factor of Q ≥ 1800, and a reflection of 86%, and can detect the refractive index changes as low as Δn = 0.002 (around n = 1.0). The lineshape, Q-factor, and resonant wavelength of the transparency spectrum can be controlled by tailoring the structural parameters. Our work also has potential application in switching, filtering, and spectral shaping.

Two-dimensional materials have emerged as new type of smart materials that may impact advanced photonic devices. Here, to increase the light absorption, a black phosphorus-based nanostructure is proposed. The presented nanostructure has a grating-shaped structure based on monolayer/multilayer black phosphorus and silica. To access reasonable absorption, the structure is numerically simulated by the finite difference time domain (FDTD) method. To benchmark this nanostructure, the black phosphorus permittivity in the wavelength range of 5 to 15 μm was calculated, to achieve the transfer spectrum based on the lateral length changes of black phosphorus (i.e., L = 100, 150, 170 nm) and the silica substrate which is extracted from Palick experimental results; the proposed nanostructure is simulated using the FDTD method. Also, changes in the refractive index of the surroundings have been used to compute significant parameters in the nanosensors, such as sensitivity, FWHM, and FOM. The proposed nanostructure can be used in tunable absorbers in the range of infrared wavelengths.

Reconfigurable and scalable plasmonics demultiplexers have attracted increasing attention due to its potential applications in the nanophotonics. Therefore, here, a novel method to design compact plasmonic wavelength demultiplexers (DEMUXes) is proposed. The designed structures (two, four, and six-channel DEMUXes) consist of symmetrical rectangular resonators (RRs) incorporating metal nano-rod defects (NRDs). In the designed structures, the RRs are laterally coupled to metal–insulator-metal (MIM) waveguides. The wavelengths of the output channels depend on the numbers and radii of the metal NRDs in the RRs. The results obtained from various device geometries, with either a single or multiple output ports, are performed utilizing a single structure, showing real reconfigurability. The finite-difference time-domain (FDTD) method is used for the numerical investigation of the proposed structures. The metal and insulator used for the realization of the proposed DEMUXes are silver and air, respectively. The silver’s permittivity is characterized by the well-known Drude model. The basic plasmonic filter which is used to design plasmonic DEMUXes is a single-mode filter. A single-mode filter is easier to cope with in circuits with higher complexity such as DEMUXes. Also, different structural parameters of the basic filter are swept and their effects on the filter’s frequency response are presented, to provide a better physical insight. Taking into account the compact sizes of the proposed DEMUXes (considering the six-channel DEMUX), they can be used in integrated optical circuits for optical communication purposes.

A novel optical refractive index sensor is proposed and theoretically investigated by cascading a PANDA and a Mach–Zehnder interferometer (MZI) based on the Vernier effect. The PANDA acts as a filter in this structure. Also, the MZI is a function of the refractive index variation. Therefore, the MZI structure acts as a refractive index sensing element in the proposed structure. Detailed modeling and instructions are provided for the design of such devices. These are supposed to be manufactured on platforms compatible with silicon-on-insulator (SOI) complementary metal-oxide semiconductor (CMOS). It is shown that the proposed sensor reaches high sensitivity (600 m/RIU) and limit of detection (LOD 3.4 $$\times$$ 10 $$^{-5}$$ RIU), which is more sensitive than the single MZI. In addition, the sensitivity of the sensor was measured when the temperature changed from 26 to 35 $$^{\circ }$$ C. This system has many applications in the field of high-sensitivity biosensing and environmental monitoring.

The unprecedented scale and impact of the COVID‐19 pandemic have required organizations to adapt all facets of their operations. The impact on the UK water sector extends beyond engineering and treatment processes, with social, economic and environmental consequences. Semi‐structured interviews were conducted with executives from 10 UK water companies to investigate the organizational response to the pandemic, and how their response impacted operational delivery. The Safe and SuRe framework was used to structure interview questions and analysis. Emergent themes of changes to customer behaviour, changes to operational practices and industry collaboration were mapped onto the framework and a ripple effect map developed. Lessons learnt highlight a failure to adequately prepare for the scale of the threat, the success of sector‐level collaboration and a need to embrace new ways of working.

There is limited information about the current state of intermittent water supply (IWS) systems at the global level. A survey was carried out by the Intermittent Water Supply Specialist Group of the International Water Association (IWA IWS SG) to better understand the current state of these systems and challenges that water companies may have faced under COVID-19 pandemic and to capture successful management strategies applied by water utilities. The survey consisted of three parts: (1) general information about IWS systems, (2) current state of IWS and (3) resilience of IWS under COVID-19 conditions, as well as some questions about potential interventions in order to improve system performance in general and under future uncertain conditions. The survey responses were evaluated based on the Safe & SuRe resilience framework, assessing measures of mitigation, adaptation, coping and learning, and exploring organisational and operational responses of IWS utilities. Infrastructure capacity and water resources availability were identified as the main causes of intermittency in most water distribution systems, while intermittent electricity was considered as the main external cause. Participants indicated that some risk assessment process was in place; however, COVID-19 has surpassed any provisions made to address the risks. Lessons learnt highlighted the importance of financial resources, e-infrastructure for efficient system operation and communication with consumers, and the critical role of international knowledge transfer and the sharing of best practice guidelines for improving resilience and transitioning towards continuous water supply. HIGHLIGHTS Impact of COVID-19 surpassed any provisions based on risk assessment approaches.; Changes in intermittent energy supply had cascading positive and negative impacts.; Inadequate infrastructure and financial strains are the main barriers to change.; Sharing knowledge and strategic guidelines can accelerate utilities' resilience.; Transition to 24/7 supply requires technical, financial and human resources support.

In the present study, we report the first high sensitivity glucose biosensor utilizing localized surface plasmon resonance of SiO2 /gold/silver containing structure. The kretschmann is illuminated by 632 nm laser for exact detection of glucose and sensitivity enhancement. To evaluate the structure FDTD or Finite-difference time-domain Method and PML (Perfectly Matched Layer) boundary conditions are applied. The operation mechanism for detection of blood glucose is the monitoring of its refractive index. The proposed blood glucose sensor indicate that a refractive index detection range of 1–1.4 RIU, with a metal thickness variation of 10 nm–30 nm and a temperature variation of 3 K–300 K. The Surface plasmon resonance-based kretschmann configuration biosensor obtained the highest sensitivity of 1050 nm/RIU with a compact size.

Label-free monitoring of biomaterials has become spotlight topic for the advanced nano-biosensing fields. In this regard, a non-destructive doping-less tunneling carbon nanotube field effect transistor (DL-TCNTFET) -based biosensor using the charge plasma concept is introduced. In doping-less structures, source and drain are created using the concept of charge plasma and by selecting appropriate work function of source and drain metals. The sensitivity of DL-TCNTFET is investigated in terms of dielectric constant variations at different bias conditions. The simulation is carried out in the ballistic regime by simultaneously solving the Poisson and Schrodinger equations in a self-consistent way using the non-equilibrium Green’s function in the form of state space approach. Simulations show that the DL-TCNTFET has better ambipolar behavior and also lower OFF current by reducing the dielectric constant of biomolecules. In addition, the ON current and biosensor sensitivity are significantly improved by increasing the dielectric constant.

In this essay, a tunable metamaterial-based biosensor is proposed for simultaneous monitoring of blood components including cells, plasma, water, thrombus, and urine components as well as glucose, albumin, and urea. The proposed biosensor is based on optical sensors, and it provides real-time, label-free, and direct detection, small size, and cost-effectiveness that can be an alternative tool to other conventional methods. The influence of operating frequency, sample thickness, temperature, and radiation angle on the performance of the sensor is investigated by the finite element method (FEM). Numerical results show that the maximum sensitivity and figure of merit (FoM) in the high frequency are 500 (nm/RIU) and 2000, and for low frequency are 136 (µm/RIU) and 155, respectively. The footprint of the structure is 0.34 µm2, which is remarkably smaller than the other reported biosensing structures. The proposed biosensor has the potential to provide high sensitivity, high FoM, and a wide operating range for biomedical applications.

In this manuscript, a plasmonic refractive index sensor with two sequential ring resonators is presented. Due to the dual-band unidirectional reflectionless light propagation phenomena, both the sensitivity and figure of merit are improved. The finite-difference time-domain (FDTD) method is used to simulate the structure numerically. Moreover, the device is investigated analytically, using the coupled-mode theory (CMT). A good agreement between the analytical and numerical results is observed. The proposed device indicates a high sensitivity of ∼1000 nm/RIU, a significant figure of merit of 133 RIU−1, and a large quality factor of 132.8 for sensing different materials with the refractive indices of n = 1, 1.2, 1.3, 1.4, 1.5, and 1.6. Also, the presented structure is investigated as a temperature sensor in which the sensitivity to the temperature changes is obtained as 0.41 nm/°C.

Thermo-optic mechanism for plasmonics sensing of terahertz radiations is numerically and analytically investigated for metasurface formed from Graphene/SiO2 and simulated at room temperature. For this purpose, here, by considering coupling condition as well as strong light-matter interaction in graphene metasurface a very compact footprint in less than half of the wavelength is proposed. Also, for deep benchmark of structure at different temperature, tunable optical properties of graphene is considered. Subsequently, the numerical operation of the sensor fulfilled based 3-dimension finite-difference time-domain (3D-FDTD) and also, the transfer matrix method (TMM) modelling is introduced. In order to investigate the relationship between the temperature variation and tunable behavior of the structure on the performance parameters, temperature is increased from 0 to 600 K in steps of 300, whereas the other parameters were fixed. Numerical results show that the max sensitivity and figure of merit (FoM) are more than 1140 nm/RIU and 5.1, respectively. Then, we numerically simulate the optical cross-section including absorption, scattering and total of them. Also, by harnessing of graphene’s surface conductivity properties, we indicate the giant tunability and minimum transmittance of % 0.02 in frequency of 14 THz in which the best track of optical performance over a wide range of frequency is occurred. Eventually, a novel research direction of the software-defined metasurface is explained, which is tried to achieve the graphene-based metasurface toward unique in controllability and harnessing of the light. This proposed thermo-optical metasurface structure can be used as a nanosensor for exciting surface plasmons.

Aim: Although, the effectiveness of metformin in diabetes treatment is well established, its preventive effect in the development of diabetes is still unclear in real world. We aimed to determine the effectiveness of metformin therapy as a single preventive agent in patients with prediabetes in a cohort study (IDPS). Study Design: In this prospective observational study. Place and Duration of Study: Isfahan Endocrine and Metabolism Research Center, Isfahan University of Medical Sciences, Isfahan, Iran. Methodology: We included 410 patients with prediabetes (168 metformin user, 242 non-users), who participated in IDPS. To determine the association between metformin use and incidence of type 2 diabetes, Cox proportional hazard method, Kaplan-Meier and log Rank test were used. Results: In fully adjusted model for all confounders, significant hazard ratio (HR) for staying prediabetes rather than returning to normal was detected in male group of metformin non-user (HR: 2·41 [95% CI 1.01-5.79]; P

In this paper, two optimization algorithms (randomly initialized hill climbing and genetic algorithms) are considered to design broadband polarization converters based on coded metasurfaces. A pixeled graphene patch with an elliptic structure is proposed for the initial solution. Each pixel can be 1 and 0 which represents the presence and absence of the graphene. The initial guess tends to the optimum configuration after several optimization processes. Four broadband polarization converters are designed utilizing the optimization algorithms. By changing the chemical potential of graphene, the operation frequency of the polarization converters can be adjusted. Furthermore, the effects of relaxation time of graphene and incident angle on the polarization conversion bandwidth of the four designed structures are investigated.

Pneumonia merupakan salah satu penyebab kematian balita di dunia. Oleh karena itu kasus pneumonia merupakan masalah kesehatan dunia. Di Puskesmas II Denpasar Selatan, kasus pneumonia balita tahun 2010 meningkat dua kali dibandingkan tahun sebelumnya. Kondisi wilayah kerja Puskesmas II Denpasar Selatan yang cukup padat bangunan berpengaruh terhadap intensitas pencahayaan alami. Penelitian ini bertujuan untuk mengetahui hubungan pencahayaan alami terhadap kejadian pneumonia pada bayi dan anak balita di Wilayah Kerja Puskesmas II Denpasar Selatan. Sampel penelitian ini adalah 30 bayi atau anak balita yang terdiagnosa pneumonia sebagai sampel kasus dan 30 orang bayi atau anak balita yang tidak terdiagnosa pneumonia yang disesuaikan dengan umur serta jenis kelaminnya. Data dikumpulkan melalui wawancara dengan kuesioner dan pengukuran kemudian dianalisis secara deskriptif dan Mc Nemar dengan tingkat kemaknaan 5%. Hasil penelitian ini menunjukkan ada hubungan bermakna antara pencahayaan alami ruang tidur (OR = 16, p = 0,00, CI 95% = 2,13–120,47) dan kepadatan hunian (OR = 13, p = 0,002, CI 95 %= 1,69–99,8) terhadap kejadian pneumonia pada bayi dan anak balita. Disarankan kepada orang tua untuk meningkatkan prilaku sehat dengan membiasakan masuknya cahaya matahari pagi dan kesadaran akan tempat tinggal yang sehat. Bagi petugas kesehatan disarankan untuk dilakukan promosi kesehatan yang berkaitan dengan faktor risiko serta cara pencegahan pneumonia.

Metamaterials are manmade structures that have attained considerable attention over the past 2 decades in the modern fields like cloaking, sensing, and imaging owing to their ability to harness electromagnetic fields. In this regard, we have inspected the dielectric properties of the hyperbolic metamaterials (HMM) made of metallic nanorods and dielectric medium at the infrared wavelength regime. The periodically arranged subwavelength-sized metallic nanorods embedded in the silicon dioxide ( $$\text{SiO}_2$$ ) substrate glass. The spacing between two adjacent nanorods is of subwavelength in size. Furthermore, effective permittivity of the metamaterial has been analyzed by employing the Maxwell Garnett effective medium theory. Moreover, different metallic nanorod inclusions (Au, W, Pt and Ti) were taken into account. Hyperbolic features of the metamaterial have been observed, and it is noticed that hyperbolic features merely depend on the type of metallic nanorods and their size. The observations reveal that the dielectric properties of the metamaterial can be tuned by altering the radii of the metallic nanorod. Apart from dispersion, reflection, transmission and absorption features of the HMM are taken into account. It is noticed that reflection, transmission and absorption of the HMM depend on the type of metallic nanorod and its dimension. Such HMMs structures with exotic dielectric features would be useful for sensing, filtering, and absorption applications.

Plasmon-induced transparency (PIT) is a spotlight technique for environmental monitoring. In this regard, a highly sensitive and tunable multilayer sensor including Ag–SiO2–Ag is presented in near-infrared range for both transverse mode (TE) and transverse mode (TM) modes at different incident waves. Actually, the proposed multilayer plasmonic sensor is presented to study the optical and sensing properties at near-infrared frequencies based on 3D finite-difference time-domain (FDTD). Sensitivity and tunability of all optical sensors are important parameters in their design, which are calculated based on propagation properties including absorption and reflection spectra, numerically and analytically. Results of absorption and reflection show that the proposed sensor has max sensitivity of 693.8 nm/RIU by Δn = 0.05 changing of middle refractive index and figure of merit (FoM) equal to 9.8. Also, the proposed nano-scale sensor can operate as a light propagation controlling with slow and fast light and multispectral sensor. By using silver metal in the sensor structure, the fast and slow light coefficient is obtained at 220 and 70, respectively. In addition, by increasing the incident angle of light, multiabsorption peaks are created which can be used as multiwindow sensor and PIT. The analytical results are in good agreement with the obtained results of coupled mode theory (CMT) method.

In this paper, a metal-insulator-metal plasmonic biosensor based on two adjacent disk resonators and the unidirectional reflectionless propagation effect is proposed and investigated. The numerical results obtained from the finite difference time domain simulations are verified analytically by means of the coupled-mode theory. The resonant properties of the proposed structure including the full-width at half-maximum and quality factor are optimized by determining the suitable geometrical parameters. The presented biosensor is then utilized to detect some biomaterials such as ether, ethyleneglycol, chlorobenzene, and quinoline. It is shown that the proposed structure shows high sensitivity of ~1500nm/RIU, large figure of merit of 242.66RIU−1 and large quality factor of 242.8, compared to the previously reported optical biosensors. Moreover, the effect of the dielectric used in the waveguides is also inspected.

Plasmonic pressure sensors play a major role in advanced applications due to their unique properties including their small footprint and high sensitivity. The design of sensors with a wide pressure range and high sensitivity, especially at low pressure (0–5 KPa), is in high demand. To this end, here, a tunable, ultra-sensitive and wide-range plasmonic pressure sensor based on nanostructure gratings is proposed. We present a numerical method for designing a pressure sensor based on surface plasmon resonance (SPR) that can adjust the coupling state by varying the surface of the metal grating. The design is based on grating coupling changes according to the pressure applied. We used grating coupling for phase matching between light and surface plasmon polaritons (SPP). The light reflection output from the grating surface is proportional to the input pressure, where we illustrate that the SPR pairing state can be controlled by varying the grating pitch by changes in pressure applied to the diaphragm. In our numerical simulation, we consider solid deformation and transmission or reflection of light using the finite-difference time-domain (FDTD) and finite element method (FEM) to simulate the optical and mechanical properties, respectively. The many advantages of the proposed sensor include nanoscale, integrability, tunability, low power, low cost and wide pressure range. This sensor is capable of detecting pressure in the range of 0–1 kPa.

Background The purpose of this cross-sectional study was to evaluate the prevalence of malocclusion in children with autism spectrum disorders (ASDs) and to determine the most common occlusal traits. Materials and Methods The present cross-sectional study was conducted among 7-15 years old children with ASDs and randomly selected healthy children with the same demographic characteristics. Molar relationship, lip incompetence, overbite, overjet, midline deviation, crossbite, and crowding/spacing were recorded. A descriptive analysis was performed for all variables. A comparison of the presence or absence of malocclusion traits between children with and without ASDs was assessed using the chi-square test. Univariate and multivariate logistic regressions were used to calculate odds ratio (OR) and 95% confidence intervals (95% CI) to assay various parameters between autism and non-autism group. Results A total of 96 patients were assessed, 47 patients in the ASD group, and 49 in the control (non-ASD) group. The results showed no significant difference between the ASD and control groups in terms of the overall prevalence of malocclusion (P>0.05). However, the prevalence of increased overjet and Class II molar relationship was significantly higher in the ASD group compared to the control group (P=0.03). Patients in the control group showed a higher prevalence of midline deviation (P=0.001). Conclusion Despite a higher prevalence of overjet and Class II molar relationship in children with ASDs, the prevalence of malocclusion was not higher in this group of patients.

Background & objectives: The management of healthcare wastes is receiving greater attention because of the risks to both human health and the environment caused by inadequate waste management practices. In that context, the objective of this study was to investigate the hospital solid waste management in Kermanshah city, Kermanshah province, Iran based on Ministry of Health and Medical Education checklist which is related to environmental health of hospitals. Methods: This study (qualitative-quantitative) was performed in two interval time in two consecutive years through a valid checklist of waste management process of Iranian Ministry of Health which include all steps of medical waste management. The quantity of hospital waste produced was measured during one week in autumn session during study interval. Results: The results of this study showed that the total averages of desirability in waste management compared to health standards in Kermanshah city hospitals were 70.38 ± 15.5 and 74.3 ± 14.8 in 2015 and 2016, respectively. The average desirability of waste management in governmental, military, private and social hospitals improved from 61 to 65.14, 75 to 79, 87 to 90 and 84.5 to 86%, respectively in two years of study interval. The average (weighted mean) of total hospital wastes generation rate (in Kermanshah city) was 4.06 kg/bed-day and for governmental, military, private and social hospitals were 4.69, 3.26, 2.7 and 1.62 kg/bed-day, respectively. The results indicated that there was a significant correlation (p < 0.05) between hospital active bed and medical wastes production. Conclusion: From the results of this study, the score of waste management practices in Kermanshah hospitals are evaluated as moderate. Therefore, more efforts, monitoring and control should be implied to achieve the desired state of hospital waste management

Morphology of glenoid fossa might help the clinician in the diagnosis, establishing more biological treatment modalities and treatment response between patients with different skeletal malocclusions. This study aimed to assess the glenoid fossa morphology in different sagittal facial types using CBCT. The CBCT images of 64 patients with normal vertical growth patterns were classified into class I, class II, and class III based on the skeletal sagittal analysis. Depth, width, and angle of glenoid fossa were measured and assessed on CBCT images. One-way analysis of variance (ANOVA) and Tukey post-hoc test were used to compare mean values among the groups. There was a significant statistical difference in means of glenoid fossa' width between groups with skeletal class III and skeletal class I (P value: 0.038). However, no significant statistical differences were found in angle(P value = 0.18) and depth (P value = 0.40) of glenoid fossa among 3 groups. This study showed the glenoid fossa in class I patients was wider than class III patients. There were no statistically significant differences in the angle and depth of glenoid fossa in patients with a different sagittal skeletal pattern.

Background Despite successful clinical outcomes of biologic medications in patients with chronic rheumatic diseases, some considerable adverse effects such as infections remain a major concern. Possibility of tuberculosis (TB) reactivation over treatment with anti-tumor necrotizing factor (TNF) alpha agents has necessitated a screening test before initiation of treatment. However, screening over the course of treatment is not recommended in those patients with negative baseline screening tests. This study aimed to evaluate the efficacy of tuberculin skin test (TST) before treatment in patients with chronic rheumatologic diseases who were indicated to receive anti-TNF-alpha therapy and the necessity of repeating this test over the course of treatment. Methods In this prospective study, patients with chronic rheumatologic diseases receiving anti-TNF-alpha agents were studied in a two-year period. TST was performed before treatment and those with positive results were excluded from the study. Thereafter, treatment with anti-TNF-alpha agents was initiated with the indicated dose. TST was repeated before administration of biologic treatment until TST became positive or 16 weeks after the initiation of treatment with anti-TNF-alpha. Results A total of 51 cases were studied, of whom one patient (1.9%) was excluded due to positive TST before treatment. All participants received infliximab and the TST test became positive in one patient (2%) 2 weeks after receiving the first dose. Also, the results of further tests at weeks 6, 10, and 14 were all negative for the remaining patients. Conclusion Due to the possibility of TST conversion after administration of anti-TNF-alpha therapy, it is important to consider TB monitoring in patients under treatment with these agents using available methods such as TST.

Here, we indicate that metasurface-based biosensors consisting of silver-metasurface with SiO2 and working in the near-infrared (NIR) spectral range can obtain simultaneous high-sensitivity and high-tunable detection of biomaterials including ether with n = 1.3, ethylene glycol with n = 1.4, chlorobenzene with n = 1.5, and quinolone with n = 1.6, where n is refractive index. Using 3D-FDTD method, we numerically extract the optical characteristics of the metasurface sensor and validate by quasi analytic coupled mode theory (CMT). By changing the refractive index of the dielectric layer, maximum sensitivity equal to 658 nm/RIU for Δn = 0.25 is achieved, so it can be able to use in high sensitive plasmonic sensors. Also the results show that the proposed metasurface sensor can be used as a multi-usage structure, such as biomaterial distinguish and identify TE and TM polarization at 40° incident angle (anisotropy in TE mode absorption spectra). Moreover by using silver as the metal layer, maximum and minimum group indexes are achieved as 350 and 486, respectively, so it is a good choice to utilize in harnessing of slow/fast light propagation. The overall size of the sensor is 540 nm × 540 nm × 560 nm, hence is a proper candidate for nanoscale sensor.

Optofluidic dye laser devices have great potential as coherent light sources for lab-on-a-chip applications such as sensing and spectroscopy applications, owing to their promising properties such as wide wavelength-tunability, proper microfluidic integration, and an extremely miniaturized footprint. The wide emission spectrum of dye molecules and narrow free spectral range of ring resonators, make these lasers inherently multi-mode. In this article, two polydimethylsiloxane-based miniaturized optofluidic ring resonator dye lasers are numerically designed and investigated. First, multi-mode lasing from a single optofluidic ring resonator with a spectral linewidth of 10 nm and a threshold energy density of $2.2~{\mu }\text{j}$ /mm2 is demonstrated. Then, by exploiting two coupled optofluidic ring resonators and Vernier effect, single-mode lasing at a center wavelength of 566 nm with a spectral linewidth as small as ${5.36}\times {10}^{-{4}}$ nm is achieved. Moreover, simulations demonstrate the sensitivity of 500 nm/RIU for the proposed dye laser sensor.

Introduction: In most ancient cultures, honey has been used for both nutritional and medical purposes. Objectives: In this research, phenolic extracts of four Iranian honeys were evaluated to determine the antioxidant potentials using DPPH (2,2-diphenyl-1-picrylhydrazyl) radical scavenging, nitric oxide (NO) radical scavenging and reducing power by ferric reducing activity of plasma (FRAP) method. Additionally, anti-diabetic properties of honey and phenolic extracts were evaluated by determination of α-amylase and α-glucosidase inhibition. Patients and Methods: Besides, reducing potential was evaluated by ferric-reducing antioxidant power method. Moreover, determination of phenolic and flavonoid contents was performed. Moreover, inhibition of α-amylase and α-glucosidase of honey and phenolic extracts were evaluated. Results: With considering to antioxidant potentials, Gavan (Astragalus) sample showed the greatest phenolic (3817±1.52 mg GAE/100 g), flavonoid contents (3.1±0.005 mg QE/100 g), and DPPH radical scavenging (IC50 = 2±0.003 mg/mL). Bahareh honey had the highest NO radical scavenging (IC50=0.0403±0.0009 mg/mL) and Meymand honey possessed the highest reducing potential by FRAP method (IC50=0.0018±0.000003 mg/mL). The maximum inhibition of α-glucosidase was shown in Meymand honey extract (46±0.1%). After sugar isolation, Zataria honey had the highest inhibition of α-glucosidase (54±0.6%) and the mode of α-amylase inhibition was noncompetitive by this honey. Whole extract (23±0.1%) and phenolic extract of Gavan honey presented the maximum inhibition of α-amylase (31.2±0.1%). Conclusion: Honey samples showed antioxidant potentials and anti-diabetic properties by retardation of α-amylase and α-glucosidase.

Plasmonics advanced materials with the capability of environmental variation detection extend the application of visible light, satisfying the demands of less footprint, easy-to-use, and high tunability for visible-sensitive materials. In this area, localized surface plasmon can significantly enhance the electric field smaller than the radiation wavelength providing a strong gradient force required in optical tweezing systems. Owing to this beneficial advantage over the conventional optical tweezers, the plasmonic tweezers have matured to a stage where today become increasingly attractive for trapping and manipulation of nanoparticles. In this work, we are proposing a tunable plasmonic nano-tweezer that operates according to the polarization of excitation laser light. The proposed novel structure encompasses a gold nano-ring and a gold nano-disk in which by changing the beam polarization, the hot spots position also changes, and the nanoparticles can be relocated around the circumference of a circle trapped at a certain point. According to 3D finite-difference-time-domain simulations, the proposed nano-tweezing system can potentially exert a trapping force of 164 pNW-1 on a 20 nm HIV-1 virus-like particle.

In this paper, a multilayer/monolayer black phosphorus (BP)-based nanostructure is presented to detect the avian influenza virus. The nanostructur is a grating arrangement made of BP over SiO2 or Al2O3 substrate. To achieve the transmission spectrum, depend on the changes in the lateral length of BP, namely (L = 100, 150, 170 nm) as well as the complex refractive index of each of three viruses types (H1N1, H5N2, H9N2) in the THz range, the structure is numerically simulated by 3D Finite Difference Time Domain (3D-FDTD) method. The change in resonance frequency is greater for the H9N2 virus because the real part of its refractive index is relatively larger. Here, too, the rate of change is examined based on the different thicknesses of the H9N2 virus. Also, changes in the refractive index of the environment have been used to calculate important parameters in the sensors, such as sensitivity, FWHM, and figure of merit. Overall, this platform provides a promising platform for detecting influenza viruses.

Introduction Human gut microbiota plays a crucial role in providing protective responses against pathogens, particularly by regulating immune system homeostasis. There is a reciprocal interaction between the gut and lung microbiota, called the gut-lung axis (GLA). Any alteration in the gut microbiota or their metabolites can cause immune dysregulation, which can impair the antiviral activity of the immune system against respiratory viruses such as severe acute respiratory syndrome coronavirus (SARS-CoV) and SARS-CoV-2. Areas covered This narrative review mainly outlines emerging data on the mechanisms underlying the interactions between the immune system and intestinal microbial dysbiosis, which is caused by an imbalance in the levels of essential metabolites. The authors will also discuss the role of probiotics in restoring the balance of the gut microbiota and modulation of cytokine storm. Expert opinion Microbiota-derived signals regulate the immune system and protect different tissues during severe viral respiratory infections. The GLA’s equilibration could help manage the mortality and morbidity rates associated with SARS-CoV-2 infection.

The concept and analysis of a nano-scale multifunctional logic gate based on graphene/hexagonal boron nitride (h-BN) plasmonic waveguides at a wavelength of 7.5 µm are presented. By using graphene as a metamaterial with outstanding electro-optical properties, various logical operations including AND, OR, and XOR are implemented. The proposed multifunctional structure supports surface plasmons (SPs) whose dispersion properties can be controlled by applying an electrical field to graphene. The effects of the incident polarisation and the substrate of graphene on the transmission of SPs are investigated. Simulations by finite difference time domain method show that the extinction ratios for the presented logical operations are higher than 15 dB. Also, the structure has a compact footprint of 1.12 µm2 which is suitable for using in integrated photonic circuits. This provides a path for the development of novel nano-scale practical on-chip applications such as plasmonic memory devices.

In recent years, usage of novel non-Si materials as the gate channel region in next generation of field effect transistors, including carbon nanotubes, have been in the spotlight of nanoelectronics research due to astounding carrier transport and I-V characteristics. These properties make them a highly suitable platform in modern radio frequency applications. Therefore, the aim of this work is to design and investigate the performance of current-starved and skewed ring oscillators based on ballistic carbon nanotube transistors (CNTFETs). In this work, we have utilized wrap-gate structure to have a better electrostatics control and mitigate the gate leakage current. All the CNTs in both n-type and p-type transistors have 0.9 nm diameter and an array of CNTs have been exploited in the gate region to achieve low-power and high-performance operation. The simulation results demonstrate that the proposed CNTFET-based ring oscillators have sub-100μW power consumption (Pcurrent-starved = 6.011 μW, Plow-skew = 67.2 μW, and Phigh-skew = 23.5 μW) along with wide frequency tuning range (fcurrent-starved = 0.202 GHz − 1.205 GHz, flow-skew = 0.361 GHz − 2.137 GHz, and fhigh-skew = 0.335 GHz − 2.38 GHz) which are suitable for internet of thing (IoT) devices operating from 100 MHz to 5.8 GHz. Finally, based on the simulation results, we have emphasized that the CNTFET-based skewed ring oscillators are suitable for high-speed purposes, while the CNTFET-based current-starved ring oscillator is recommended for low-power and high-swing applications.

Greywater recycling and rainwater harvesting have the potential to increase the resilience of water management and reduce the need for investment in conventional water supply schemes. However, their water-savings would partly depend on the location and built-form of urban development and hence its household sizes and rainwater per dwelling. We have therefore tested how spatial planning options would affect the future viability of alternative water supply in the Greater South East of England. Our integrated modelling framework, for the first time, forecasts the future densities and variability of built-form to provide inputs to the modelling of alternative water supply. We show that using projections of the existing housing stock would have been unsound, and that using standard dwelling types and household sizes would have substantially overestimated the water-savings, by not fully representing how the variability in dwelling dimensions and household-sizes would affect the cost effectiveness of these systems. We compare the spatial planning trend over a 30 year period with either compaction at higher densities within existing urban boundaries, or market-led more dispersed development. We show how the viability of alternative water supply would differ between these three spatial planning options. The water-savings of rainwater harvesting would vary greatly at a regional scale depending on residential densities and rainfall. Greywater recycling would be less affected by spatial planning but would have a finer balance between system costs and water-savings and its feasibility would vary locally depending on household sizes and water efficiency. The sensitivity of the water savings to differences in rainfall and water prices would vary with residential density. The findings suggest that forecasts of residential densities, rainfall and the water price could be used in conjunction with more detailed local studies to indicate how spatial planning would affect the future water saving potential of alternative water supply.

Carbon nanotube transistor is a spotlight components for toxic gas monitoring. In this regard, we present a new toxic gas molecules sensor base on a single-walled carbon nanotube transistor and use the Poisson and Schrodinger equations in a self-consistent manner and is modeled using non-equilibrium Green’s function. The reaction between gaseous molecules and single-walled carbon nanotubes can harness the charge and potential level inside the channel, which changes the electrical characteristics of the device. Investigations carried out over a 20-nm channel and at a temperature range between 200 and 400 K shows that the conductivity and current–voltage characteristic of the proposed Nano-sensor depend on temperature and gas conditions. According to the simulation results, the decrease in the temperature decreases the OFF-state current of the tunneling carbon nanotube field-effect transistor which leads to a decrease in the leakage current and the band-to-band tunneling. In addition, due to the temperature rise, the sensitivity is increased, and by increasing the dielectric constant of the gas, the on-state current of the device will also increase significantly. The maximum sensitivity for Carbonyl Chloride is 630 (nm/RIU).

Surface plasmon resonance (SPR) is a spotlight technique for environmental monitoring. In this regard, an optical gas sensor based on SPR is investigated and analyzed here. The sensor is used for detection of toxic gases such as cyanogen, ethanol, propane, nitrogen dioxide, and phosgene. The performance of the sensor is inspected and optimized by considering different parameters such as the thickness of the metal layer, the material used for the prism, and the incident light angle and wavelength. The finite-difference time-domain method is used for simulation, and the optimization algorithm is particle swarm optimization. Simulation results show that the best metal thickness for gold, silver, aluminum, and copper is 44.39 nm, 43.16 nm, 18.195 nm, and 32.5 nm, respectively. Also, utilizing different materials such as SiO2, PMMA, BCB, MgF2, and cyclomer for the prism and the effect of temperature variation on these materials are studied, and it is shown that MgF2 demonstrates better performance. Furthermore, the results of the optimization indicate that the most suitable incident light angles (wavelengths) are 44.43° (900.59 nm), 45.5° (599.7 nm), 44.56° (300.1 nm), and 44.41° (899.4 nm) for gold, silver, aluminum, and copper, respectively. The sensor shows the best full-width at half-maximum and quality factor (Q) of 4.2 nm and 214.28, respectively, for the combination of MgF2 prism and a gold layer. The maximum sensitivity and figure of merit for gold layer are >120 (nm/RIU) and >20, and for copper layer are >270 (nm/RIU) and >30, respectively.

In the present paper, we aim to report a simple, highly sensitive, and compact footprint biosensor for cancer detection based on metamaterial containing structure utilizing theoretical model. This model includes of array of split ring resonators on a dielectric substrate. The proposed structure is simulated using three-dimensional finite-element method. To achieve the appropriate operation, the effects of the physical properties including dielectric material, and different cells on the performance of the proposed sensor are considered. For this purpose, three types of dielectrics, including silicon dioxide (SiO2), titanium dioxide (TiO2), and polymethyl methacrylate (PMMA) substrates have been used to evaluate the biosensor. Calculated sensitivity values for SiO2, TiO2, and the PMMA are 658, 653, and 633, respectively, while the figure of merit for these three sub-layers are 258, 2431, and 225. According to the simulation results, when the refractive index of a sub-layer is closer to the refractive index of the samples, the sensor is more sensitive. Also, due to the nanometer size of SSRs, it is easy to detect nanometer-sized specimens. The biosensor has a very high resolution so that the capability of measurement and the detection of cancer cells are enhanced.

Using the metallic nano-antennas we can enhance the intensity of a laser pulse to prepare it for high-order harmonic generation. Plasmonic resonances in the metal surfaces cause a non-homogeneous enhancement of the incoming laser field. In this article behavior of the generated high-order harmonics and attosecond pulses with respect to the location of a helium ion in the non-homogeneous field is investigated. It is cleared that the broader supercontinuum can be observed for the case when the ion target located around the center of non-homogeneity which leads to more intense and shorter attosecond pulses.

The experimental and theoretical evaluation of a simple, low cost, and compact footprint, as well as a high resolution graphene plasmonics sensor are presented here for optical scanning. The strong coupling condition between incident light and excited surface plasmon resonance (SPR) of the graphene-SiO2/Si structure is thoroughly utilized to assay the proposed model. The substrate thickness, incident angle, and coupling conditions are considered to obtin optimal results including the highest resolution, and physical and optical properties including graphene thickness. The results show that high-resolution condition can be provided when the chemical vapor deposition monolayer graphene thickness is 0.335 nm, SiO2/Si thickness is 300 nm, and incident angle is $\theta $ = 62.5 °. Moreover, atomic force microscopy (AFM) and scanning electron microscopy (SEM) are employed to obtain and investigate the physical structures. Finally, it is shown that the highest sensitivity can be achieved by a strong coupling condition.

This paper reports the numerical investigation of the Talbot effect for biomaterial detection at optical frequencies. Cytop polymer grating Plasmonics structure with periodicity comparable to the incident wavelength are applied to evaluate of the plasmonics Talbot biosensor. Significant sensitivity from the proposed Talbot biosensor is obtained. For this purpose, the effect of the different biomaterials including Ether, Ethyleneglycol, Chlorobenzene and Quinoline on plasmonics Talbot effects at wavelength range of 550-650 nm are then inspected to improve the structural parameters of the biosensor. Also, the sensitivity and figure-of-merit are calculated. Our numerical results show that the proposed biosensor are able to operate as a high sensitivity with maximum FOM of 20.99, and sensitivity of 324 nm/refractive index unit for small change of $$\Delta n$$ = 0.4, in the refractive index of biomaterials. We believe that the proposed biosensor can be applied as a label free on-chip biosensor.

Inflammatory bowel diseases (IBDs) are immune-mediated, chronic relapsing diseases with a rising prevalence worldwide in both adult and pediatric populations. Treatment options for immune-mediated diseases, including IBDs, are traditional steroids, immunomodulators, and biologics, none of which are capable of inducing long-lasting remission in all patients. Dendritic cells (DCs) play a fundamental role in inducing tolerance and regulating T cells and their tolerogenic functions. Hence, modulation of intestinal mucosal immunity by DCs could provide a novel, additional tool for the treatment of IBD. Recent evidence indicates that probiotic bacteria might impact immunomodulation both in vitro and in vivo by regulating DCs’ maturation and producing tolerogenic DCs (tolDCs) which, in turn, might dampen inflammation. In this review, we will discuss this evidence and the mechanisms of action of probiotics and their metabolites in inducing tolDCs in IBDs and some conditions associated with them.

The file attached to this record is the author's final peer reviewed version. The Publisher's final version can be found by following the DOI link. Complexity in water distribution systems (WDSs) poses a challenge for analysis and management of the systems. To reduce the complexity, the recent development of complex network science provides a system decomposition technique that converts a complex WDS with a large number of components into a simple system with a set of interconnected modules. Each module is a subsystem with stronger internal connections than external connections. Thus far, the topological features of the modular structure in WDS have been extensively studied but not the behavioural features, e.g. the hydraulic interdependencies among modules. Therefore, this paper aims to quantitatively measure and graphically visualize the module interdependency in WDSs, which helps understanding the behavioural complexity of WDSs and thus various WDS analyses, such as pipe maintenance, model calibration, rehabilitation, and District Metered Areas planning. Specifically, this study first identifies the WDS’s modular structure then measures how changes in the state of one module (i.e. any single pipe failure or perturbed demand within each module) affect the state of another module. Modular interdependencies are summarized in an interdependency matrix and visualized by the digraph. Four real-world systems are analysed, and three of them shows low interdependencies among most of the modules and there are only a few critical modules whose status changes will substantially affect a number of other modules. Hence, highly interconnected topologies may not result in strong and complex module interdependency, which is a fact that simplifies several WDS analysis for practical applications as discussed in this paper.

In recent times, the family of rowhammer attacks have posed major security threats. Assessing the rowhammer vulnerability of DRAM modules during post-manufacturing test as well as system development and in-field deployment is a crucial step towards detecting and mitigating it. Detection of rowhammer vulnerable cells is quite challenging due to random physical factors and memory constructions, and very exhaustive leading to time and cost overhead. In this paper, we propose an efficient test framework, called RHAT, to address this concern. RHAT can be employed for both manufacturing test and in-field (deployment) test. It first develops a non-invasive approach to efficiently reverse engineer the address scrambling on DRAM. It then identifies critical vulnerability features by spatial correlation analysis of memory cells. Finally, it offers a fast test algorithm to detect rowhammer-vulnerable cells using smaller representative memory array based on the correlation analysis. We implemented and validated RHAT on DIMM samples from three different DRAM vendors showing significant correlation with satisfactory test coverage and time.