[A qualitative study of shared decision making related to psychotropic drugs in adolescence]. / Kwalitatief onderzoek naar gedeelde besluitvorming over psychofarmaca bij jongeren.

BACKGROUND: Shared decision making (SDM) is an evidence-based model that involves the collaborative development of a treatment plan. SDM in adolescents with mental health problems is complex. Most mental health problems arise in adolescence and psychotropic drugs are an important part of treatment. Previous research focuses primarily on caregivers’ experience with SDM. AIM: This research has the main objective to gain insight into the adolescents’ experience with shared decision making related to psychotropic drugs. METHODS: Qualitative research through semi-structured interviews with 12 adolescents (12-18 years old) between June and October 2021, followed by thematic analysis of the data using the systematic text condensation (Malterud). RESULTS: Four themes were identified in the analysis: 1) the adolescent wants to feel heard, 2) the adolescent needs support in forming and expressing his/her opinion, 3) SDM in adolescents is a complex trialogue, and 4) the decision-making process affects treatment and adherence. CONCLUSION: When we ask adolescents about their experience with SDM, we can learn the following:- Involve parents, but always tailor this to the individual adolescent and his context. – Put the adolescent at the center. – Dwell on the adolescent’s view on psychotropic drugs.

Low-Loss Paper-Substrate Triple-Band-Frequency Reconfigurable Microstrip Antenna for Sub-7 GHz Applications.

In this paper, a low-cost resin-coated commercial-photo-paper substrate is used to design a printed reconfigurable multiband antenna. The two PIN diodes are used mainly to redistribute the surface current that provides reconfigurable properties to the proposed antenna. The antenna size of 40 mm × 40 mm × 0.44 mm with a partial ground, covers wireless and mobile bands ranging from 1.91 GHz to 6.75 GHz. The parametric analysis is performed to achieve optimized design parameters of the antenna. The U-shaped and C-shaped emitters are meant to function at 2.4 GHz and 5.9 GHz, respectively, while the primary emitter is designed to operate at 3.5 GHz. The proposed antenna achieved peak gain and radiation efficiency of 3.4 dBi and 90%, respectively. Simulated and measured results of the reflection coefficient, radiation pattern, gain, and efficiency show that the antenna design is in favorable agreement. Since the proposed antenna achieved wideband (1.91-6.75 GHz) using PIN diode configuration, using this technique the need for numerous electronic components to provide multiband frequency is avoided.

Metamaterial inspired electromagnetic bandgap filter for ultra-wide stopband screening devices of electromagnetic interference.

Presented here is a reactively loaded microstrip transmission line that exhibit an ultra-wide bandgap. The reactive loading is periodically distributed along the transmission line, which is electromagnetically coupled. The reactive load consists of a circular shaped patch which is converted to a metamaterial structure by embedded on it two concentric slit-rings. The patch is connected to the ground plane with a via-hole. The resulting structure exhibits electromagnetic bandgap (EBG) properties. The size and gap between the slit-rings dictate the magnitude of the reactive loading. The structure was first theoretically modelled to gain insight of the characterizing parameters. The equivalent circuit was verified using a full-wave 3D electromagnetic (EM) solver. The measured results show the proposed EBG structure has a highly sharp 3-dB skirt and a very wide bandgap, which is substantially larger than any EBG structure reported to date. The bandgap rejection of the single EBG unit-cell is better than - 30 dB, and the five element EBG unit-cell is better than - 90 dB. The innovation can be used in various applications such as biomedical applications that are requiring sharp roll-off rates and high stopband rejection thus enabling efficient use of the EM spectrum. This can reduce guard band and thereby increase the channel capacity of wireless systems.

Frequency-Selective Surface-Based MIMO Antenna Array for 5G Millimeter-Wave Applications.

In this paper, a radiating element consisting of a modified circular patch is proposed for MIMO arrays for 5G millimeter-wave applications. The radiating elements in the proposed 2 × 2 MIMO antenna array are orthogonally configured relative to each other to mitigate mutual coupling that would otherwise degrade the performance of the MIMO system. The MIMO array was fabricated on Rogers RT/Duroid high-frequency substrate with a dielectric constant of 2.2, a thickness of 0.8 mm, and a loss tangent of 0.0009. The individual antenna in the array has a measured impedance bandwidth of 1.6 GHz from 27.25 to 28.85 GHz for S11 ≤ -10 dB, and the MIMO array has a gain of 7.2 dBi at 28 GHz with inter radiator isolation greater than 26 dB. The gain of the MIMO array was increased by introducing frequency-selective surface (FSS) consisting of 7 × 7 array of unit cells comprising rectangular C-shaped resonators, with one embedded inside the other with a central crisscross slotted patch. With the FSS, the gain of the MIMO array increased to 8.6 dBi at 28 GHz. The radiation from the array is directional and perpendicular to the plain of the MIMO array. Owing to the low coupling between the radiating elements in the MIMO array, its Envelope Correlation Coefficient (ECC) is less than 0.002, and its diversity gain (DG) is better than 9.99 dB in the 5G operating band centered at 28 GHz between 26.5 GHz and 29.5 GHz.

Design of a Planar Sensor Based on Split-Ring Resonators for Non-Invasive Permittivity Measurement.

The permittivity of a material is an important parameter to characterize the degree of polarization of a material and identify components and impurities. This paper presents a non-invasive measurement technique to characterize materials in terms of their permittivity based on a modified metamaterial unit-cell sensor. The sensor consists of a complementary split-ring resonator (C-SRR), but its fringe electric field is contained with a conductive shield to intensify the normal component of the electric field. It is shown that by tightly electromagnetically coupling opposite sides of the unit-cell sensor to the input/output microstrip feedlines, two distinct resonant modes are excited. Perturbation of the fundamental mode is exploited here for determining the permittivity of materials. The sensitivity of the modified metamaterial unit-cell sensor is enhanced four-fold by using it to construct a tri-composite split-ring resonator (TC-SRR). The measured results confirm that the proposed technique provides an accurate and inexpensive solution to determine the permittivity of materials.

Investigation of IL-35 and IL-39, New Members of the IL-12 Family, in Different Clinical Presentations of Brucellosis.

Brucellosis is significantly influenced by the interactions between the causative Brucella bacteria and host immunity. Recently identified cytokines have been described for their immunomodulatory effects in numerous inflammatory, autoimmune and infectious diseases. Some of them are new members of cytokine superfamilies, including several members of the IL-12 superfamily (IL-35, IL-39). The major purpose of the present study was to investigate the role of these new immunomodulatory cytokines in Brucella infections. The levels of IL-35 and IL-39 in the serum of 40 acute and 40 chronic brucellosis patients and 40 healthy controls were measured by ELISA. The mRNA levels of IL-35 and IL-39 in PBMCs were detected by RT-qPCR. Both IL-35 and IL-39 serum concentrations were significantly higher in healthy control subjects than in brucellosis patients, and IL-35 and IL-39 serum levels of chronic brucellosis patients were higher than those of acute cases. It was also found that the expression of Ebi3/IL-12A (IL-35 genes) and Ebi3/IL-23A (IL-39 genes) was upregulated in chronic brucellosis patients compared to healthy controls. Moreover, the expression of the Ebi3/IL-12A and Ebi3/IL-23A genes was lower in patients with acute brucellosis than in patients with chronic brucellosis. Overall, this study showed that IL-35 and IL-39 are positively correlated in brucellosis and significantly decreased during the disease. Significantly lower levels of IL-35 and IL-39 in acute brucellosis than in chronic brucellosis and healthy controls suggest that these cytokines may play a key role in suppressing the immune response to brucellosis and its progression to chronicity.

IL-35 and IL-39, new members of the IL-12 cytokine family, are immunomodulatory cytokines characterized as anti-inflammatory and pro-inflammatory, respectively.In acute and chronic brucellosis, serum IL-35 and IL-39 are significantly decreased.In acute brucellosis, serum IL-35 are significantly lower than in chronic brucellosis, suggesting that this cytokine may play a role in chronification.A positive correlation was found between IL-35 and IL-39 in acute and chronic brucellosis, suggesting that the common protein subunit Ebi may be suppressed.According to the results of this study, IL-35 and IL-39 may play a role in the pathogenesis of brucellosis.

High performance antenna-on-chip inspired by SIW and metasurface technologies for THz band operation.

In this paper, a high-performance antenna-on-chip (AoC) is implemented on gallium arsenide (GaAs) wafer based on the substrate integrated waveguide (SIW) and metasurface (MTS) technologies for terahertz band applications. The proposed antenna is constructed using five stacked layers comprising metal-GaAs-metal-GaAs-metal. The conductive electromagnetic radiators are implemented on the upper side of the top GaAs layer, which has a metallic ground-plane at its underside. The metallic feedline is implemented at the underside of the bottom GaAs layer. Dual wrench-shaped radiators are framed by metallic vias connected to the ground-plane to create SIW cavity. This technique mitigates the surface waves and the substrate losses, thereby improving the antenna's radiation characteristics. The antenna is excited by a T-shaped feedline implemented on the underside of the bottom GaAs substrate layer. Electromagnetic (EM) energy from the feedline is coupled to the radiating elements through the circular and linear slots etched in the middle ground-plane layer. To mitigate the surface-wave interactions and the substrate losses in the bottom GaAs layer, the feedline is contained inside a SIW cavity. To enhance the antenna's performance, the radiators are transformed into a metamaterial-inspired surface (i.e., metasurface), by engraving periodic arrangement of circular slots of sub-wavelength diameter and periodicity. Essentially, the slots act as resonant scatterers, which control the EM response of the surface. The antenna of dimensions of 400 × 400 × 8 µm3 is demonstrated to operate over a wide frequency range from 0.445 to 0.470 THz having a bandwidth of 25 GHz with an average return-loss of - 27 dB. The measured average gain and radiation efficiency are 4.6 dBi and 74%, respectively. These results make the proposed antenna suitable for AoC terahertz applications.

Electronically reconfigurable and conformal triband antenna for wireless communications systems and portable devices.

This paper presents the design of a triband antenna that can be electronically configured to operate at different frequencies. The proposed antenna is design to operate at sub-6GHz bands at 2.45 GHz (ISM, Wi-Fi, and WLAN), 3.3, 3.5 & 3.9 GHz (WiMAX), and 4.1 & 4.9 GHz (4G & 5G). This is achieved by connecting two open-ended stubs to a modified triangular patch radiator using PIN diodes. The antenna's performance was optimized using a 3D electromagnetic solver and its performance was verified through measurements. Moreover, the conformal analysis done on the antenna shows that the proposed technique can be used in moderately flexible wireless devices without compromising the antenna's gain, radiation efficiency and radiation patterns. These characteristics makes the proposed antenna applicable for various wireless communication systems and devices.

High gain/bandwidth off-chip antenna loaded with metamaterial unit-cell impedance matching circuit for sub-terahertz near-field electronic systems.

An innovative off-chip antenna (OCA) is presented that exhibits high gain and efficiency performance at the terahertz (THz) band and has a wide operational bandwidth. The proposed OCA is implemented on stacked silicon layers and consists of an open circuit meandering line. It is shown that by loading the antenna with an array of subwavelength circular dielectric slots and terminating it with a metamaterial unit cell, its impedance bandwidth is enhanced by a factor of two and its gain on average by about 4 dB. Unlike conventional antennas, where the energy is dissipated in a resistive load, the technique proposed here significantly reduces losses. The antenna is excited from underneath the antenna by coupling RF energy from an open-circuited feedline through a slot in the ground-plane of the middle substrate layer. The feedline is shielded with another substrate layer which has a ground-plane on its opposite surface to mitigate the influence of the structure on which the antenna is mounted. The antenna has the dimensions 12.3 × 4.5 × 0.905 mm3 and operates across the 0.137-0.158 THz band corresponding to a fractional bandwidth of 14.23%. Over this frequency range the average measured gain and efficiency are 8.6 dBi and 77%, respectively. These characteristics makes the proposed antenna suitable for integration in sub-terahertz near-field electronic systems such as radio frequency identification (RFID) devices with high spatial resolution.

An innovative antenna array with high inter element isolation for sub-6 GHz 5G MIMO communication systems.

A novel technique is shown to improve the isolation between radiators in antenna arrays. The proposed technique suppresses the surface-wave propagation and reduces substrate loss thereby enhancing the overall performance of the array. This is achieved without affecting the antenna's footprint. The proposed approach is demonstrated on a four-element array for 5G MIMO applications. Each radiating element in the array is constituted from a 3 × 3 matrix of interconnected resonant elements. The technique involves (1) incorporating matching stubs within the resonant elements, (2) framing each of the four-radiating elements inside a dot-wall, and (3) defecting the ground plane with dielectric slots that are aligned under the dot-walls. Results show that with the proposed approach the impedance bandwidth of the array is increased by 58.82% and the improvement in the average isolation between antennas #1&2, #1&3, #1&4 are 8 dB, 14 dB, 16 dB, and 13 dB, respectively. Moreover, improvement in the antenna gain is 4.2% and the total radiation efficiency is 23.53%. These results confirm the efficacy of the technique. The agreement between the simulated and measured results is excellent. Furthermore, the manufacture of the antenna array using the proposed approach is relatively straightforward and cost effective.

Assessment of CD39 expression in regulatory T-cell subsets by disease severity in adult and juvenile COVID-19 cases.

COVID-19 is a disease characterized by acute respiratory failure and is a major health problem worldwide. Here, we aimed to investigate the role of CD39 expression in Treg cell subsets in COVID-19 immunopathogenesis and its relationship to disease severity. One hundred and ninety COVID-19 patients (juveniles, adults) and 43 volunteers as healthy controls were enrolled in our study. Flow cytometric analysis was performed using a 10-color monoclonal antibody panel from peripheral blood samples. In adult patients, CD39+ Tregs increased with disease severity. In contrast, CD39+ Tregs were decreased in juvenile patients in an age-dependent manner. Overall, our study reveals an interesting profile of CD39-expressing Tregs in adult and juvenile cases of COVID-19. Our results provide a better understanding of the possible role of Tregs in the mechanism of immune response in COVID-19 cases.

Temperature-based phenology model for predicting the present and future establishment and distribution of recently invasive Spodoptera frugiperda (J. E. Smith) in India.

Fall armyworm, Spodoptera frugiperda (J. E. Smith) is a polyphagous and highly destructive invasive insect pest of many crops. It was recently introduced into India and widely reported in almost all parts of India. Development of a temperature-based phenology model for predicting its rate of development and distribution will help in understanding the establishment and further spread of introduced invasive insect pests. Development, survival and reproduction parameters of S. frugiperda at six constant temperature conditions (15, 20, 25, 27, 30 and 35°C) were investigated and further validated with data generated under fluctuating temperature conditions. The estimated lower developmental threshold temperatures were 12.1°C for eggs, 11°C for larvae, 12.2°C for pupae, 15.13°C for males and 12.66°C for females. Degree-day (DD) requirements for the development of the different stages of S. frugiperda were 50, 250 and 200 DD for egg, larva and pupa, respectively. The best-fitted functions were compiled for each life stage to yield a phenology model, which was stochastically simulated to estimate the life table parameters. The developed phenology model predicted temperature ranges between 27 and 30°C as favourable for S. frugiperda development, survival and reproduction. The results revealed that maximum net reproductive rate (215.66 females/female/generation) and total fecundity (981.08 individuals/female/generation) were attained at 30°C constant temperature. The mean length of generations decreased from 74.29 days at 15°C to 38.74 days at 30°C. The maximum intrinsic rate of increase (0.138 females/female/day) and shortest doubling time (4.9 days) were also observed at 30°C. Results of simulated life table parameters showed high temperature-dependent development of S. frugiperda and complete development within all the tested constant temperature ranges (15-35°C). Simulated life table parameters for predicting risk indices of S. frugiperda in India indicated a significant increase in activity indices and establishment risk indices with a higher number of generations during future (2050 and 2070) climatic change scenarios compared to present conditions. Our results indicate that India will be highly suitable for the establishment and survival of S. frugiperda in future time periods.

Optimum power transfer in RF front end systems using adaptive impedance matching technique.

Matching the antenna's impedance to the RF-front-end of a wireless communications system is challenging as the impedance varies with its surround environment. Autonomously matching the antenna to the RF-front-end is therefore essential to optimize power transfer and thereby maintain the antenna's radiation efficiency. This paper presents a theoretical technique for automatically tuning an LC impedance matching network that compensates antenna mismatch presented to the RF-front-end. The proposed technique converges to a matching point without the need of complex mathematical modelling of the system comprising of non-linear control elements. Digital circuitry is used to implement the required matching circuit. Reliable convergence is achieved within the tuning range of the LC-network using control-loops that can independently control the LC impedance. An algorithm based on the proposed technique was used to verify its effectiveness with various antenna loads. Mismatch error of the technique is less than 0.2%. The technique enables speedy convergence (< 5 µs) and is highly accurate for autonomous adaptive antenna matching networks.

High-isolation antenna array using SIW and realized with a graphene layer for sub-terahertz wireless applications.

This paper presents the results of a study on developing an effective technique to increase the performance characteristics of antenna arrays for sub-THz integrated circuit applications. This is essential to compensate the limited power available from sub-THz sources. Although conventional array structures can provide a solution to enhance the radiation-gain performance however in the case of small-sized array structures the radiation properties can be adversely affected by mutual coupling that exists between the radiating elements. It is demonstrated here the effectiveness of using SIW technology to suppress surface wave propagations and near field mutual coupling effects. Prototype of 2 × 3 antenna arrays were designed and constructed on a polyimide dielectric substrate with thickness of 125 µm for operation across 0.19-0.20 THz. The dimensions of the array were 20 × 13.5 × 0.125 mm3. Metallization of the antenna was coated with 500 nm layer of Graphene. With the proposed technique the isolation between the radiating elements was improved on average by 22.5 dB compared to a reference array antenna with no SIW isolation. The performance of the array was enhanced by transforming the patch to exhibit metamaterial characteristics. This was achieved by embedding the patch antennas in the array with sub-wavelength slots. Compared to the reference array the metamaterial inspired structure exhibits improvement in isolation, radiation gain and efficiency on average by 28 dB, 6.3 dBi, and 34%, respectively. These results show the viability of proposed approach in developing antenna arrays for application in sub-THz integrated circuits.

Realizing UWB Antenna Array with Dual and Wide Rejection Bands Using Metamaterial and Electromagnetic Bandgaps Techniques.

This research article describes a technique for realizing wideband dual notched functionality in an ultra-wideband (UWB) antenna array based on metamaterial and electromagnetic bandgap (EBG) techniques. For comparison purposes, a reference antenna array was initially designed comprising hexagonal patches that are interconnected to each other. The array was fabricated on standard FR-4 substrate with thickness of 0.8 mm. The reference antenna exhibited an average gain of 1.5 dBi across 5.25-10.1 GHz. To improve the array's impedance bandwidth for application in UWB systems metamaterial (MTM) characteristics were applied it. This involved embedding hexagonal slots in patch and shorting the patch to the ground-plane with metallic via. This essentially transformed the antenna to a composite right/left-handed structure that behaved like series left-handed capacitance and shunt left-handed inductance. The proposed MTM antenna array now operated over a much wider frequency range (2-12 GHz) with average gain of 5 dBi. Notched band functionality was incorporated in the proposed array to eliminate unwanted interference signals from other wireless communications systems that coexist inside the UWB spectrum. This was achieved by introducing electromagnetic bandgap in the array by etching circular slots on the ground-plane that are aligned underneath each patch and interconnecting microstrip-line in the array. The proposed techniques had no effect on the dimensions of the antenna array (20 mm × 20 mm × 0.87 mm). The results presented confirm dual-band rejection at the wireless local area network (WLAN) band (5.15-5.825 GHz) and X-band satellite downlink communication band (7.10-7.76 GHz). Compared to other dual notched band designs previously published the footprint of the proposed technique is smaller and its rejection notches completely cover the bandwidth of interfering signals.

Bandwidth and gain enhancement of composite right left handed metamaterial transmission line planar antenna employing a non foster impedance matching circuit board.

The paper demonstrates an effective technique to significantly enhance the bandwidth and radiation gain of an otherwise narrowband composite right/left-handed transmission-line (CRLH-TL) antenna using a non-Foster impedance matching circuit (NF-IMC) without affecting the antenna's stability. This is achieved by using the negative reactance of the NF-IMC to counteract the input capacitance of the antenna. Series capacitance of the CRLH-TL unit-cell is created by etching a dielectric spiral slot inside a rectangular microstrip patch that is grounded through a spiraled microstrip inductance. The overall size of the antenna, including the NF-IMC at its lowest operating frequency is 0.335λ0 × 0.137λ0 × 0.003λ0, where λ0 is the free-space wavelength at 1.4 GHz. The performance of the antenna was verified through actual measurements. The stable bandwidth of the antenna for |S11|≤ - 18 dB is greater than 1 GHz (1.4-2.45 GHz), which is significantly wider than the CRLH-TL antenna without the proposed impedance matching circuit. In addition, with the proposed technique the measured radiation gain and efficiency of the antenna are increased on average by 3.2 dBi and 31.5% over the operating frequency band.

Degree day-based model predicts pink bollworm phenology across geographical locations of subtropics and semi-arid tropics of India.

There is a global concern about the effects of climate change driven shifts in species phenology on crop pests. Using geographically and temporally extensive data set of moth trap catches and temperatures across the cotton growing states of India, we predicted the phenology of cotton pink bollworm Pectinophora gossypiella (Saunders). Our approach was centered on growing degree days (GDD), a measure of thermal accumulation that provides a mechanistic link between climate change and species' phenology. The phenology change was predicted by calculating absolute error associated with DD and ordinal date, an alternative predictor of phenology, for peak moth abundance. Our results show that GDD outperformed the ordinal dates in predicting peak moth abundance in 6 out of 10 selected locations. Using established thresholds of 13.0/34.0 °C, mean DD accumulated between the consecutive moth peaks across different years were estimated at 504.05 ± 4.84. Seven generations were determined for pink bollworm in a cropping season, the length of which varied between 35 and 73 days in response to temperature. Pink bollworm population reached its peak during third generation which can be the target for management actions. The study provides essential information for developing pink bollworm management strategies under climate change.

Author Correction: High-Gain Metasurface in Polyimide On-Chip Antenna Based on CRLH-TL for Sub-Terahertz Integrated Circuits.

An amendment to this paper has been published and can be accessed via a link at the top of the paper.

Improved adaptive impedance matching for RF front-end systems of wireless transceivers.

In this paper an automatic adaptive antenna impedance tuning algorithm is presented that is based on quantum inspired genetic optimization technique. The proposed automatic quantum genetic algorithm (AQGA) is used to find the optimum solution for a low-pass passive T-impedance matching LC-network inserted between an RF transceiver and its antenna. Results of the AQGA tuning method are presented for applications across 1.4 to 5 GHz (satellite services, LTE networks, radar systems, and WiFi bands). Compared to existing genetic algorithm-based tuning techniques the proposed algorithm converges much faster to provide a solution. At 1.4, 2.3, 3.4, 4.0, and 5.0 GHz bands the proposed AQGA is on average 75%, 49.2%, 64.9%, 54.7%, and 52.5% faster than conventional genetic algorithms, respectively. The results reveal the proposed AQGA is feasible for real-time application in RF-front-end systems.