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PARVAX is a genetic vaccine platform based on an adeno-associated vector that has demonstrated to elicit potent, durable, and protective immunity in nonhuman primates (NHPs) after a single dose. Here, we assessed vaccine immunogenicity following a PARVAX prime-boost regimen against SARS-CoV-2. In mice, a low-dose prime followed by a higher-dose boost elicited potent neutralizing antibody responses and distinct cross-reactivity profiles, depending on the antigen used in the booster vaccine. However, the potent neutralizing anti-vector antibody responses developed in mice limited the dose that could be administered as a prime. We further explored the re-administration efficacy in NHPs primed with a SARS-CoV-2 Delta vaccine and boosted with an Omicron BA.1 vaccine at week 15, after the primary response peak antibody levels were reached. The boost elicited an increase in antibodies against several Omicron variants, but no increase was detected in the antibody titers for other variants. The anti-vector responses were low and showed some increased subsequent boosts but generally declined over time. The potent prime vaccination limited the detection of the boosting effect, and therefore, the effect of anti-vector immunity was not fully elucidated. These data show that PARVAX can be effectively re-administered and induce a novel antigenic response. [ABSTRACT FROM AUTHOR]

Currently, artificial intelligence (AI) is emerging as a dominant force in various technologies, owing to its unparalleled efficiency. Among the plethora of AI techniques available, neural networks (NNs) have garnered significant attention due to their adeptness in addressing diverse challenges, particularly for prediction tasks. This study offers a comprehensive review of predominant AI-based approaches to photovoltaic (PV) energy forecasting, with a particular emphasis on artificial neural networks (ANNs). We introduce a revolutionary methodology that amalgamates the predictive capabilities of ANN with the precision control afforded by the minimum-risk problem and sliding mode control (MRP-SMC), thereby revolutionizing the PV panel performance enhancement. Building upon this methodology, our hybrid approach utilizes the ANN as a proficient weather forecaster, accurately predicting the temperature and solar radiation levels impacting the panels. These forecasts serve as guiding principles for the MRP-SMC algorithm, enabling the proactive determination of the Maximum Power Point (MPP). Unlike conventional methods that grapple with weather unpredictability, the MRP-SMC algorithm transforms stochastic optimization challenges into controllable deterministic risk problems. Our method regulates the boost converter's work cycle dynamically. This dynamic adaptation, guided by environmental predictions from ANNs, unlocks the full potential of PV panels, maximizing energy recovery efficiency. To train the model, we utilized a large dataset comprising 60,538 temperature and solar radiation readings from the Department of Systems Engineering and Automation at the Faculty of Engineering in Vitoria (University of the Basque Country). Our approach demonstrates a high regression coefficient (R = 0.99) and low mean square error (MSE = 0.0044), underscoring its exceptional ability to predict real energy values. In essence, this study proposes a potent fusion of artificial intelligence and control mechanisms that unleash the untapped potential of photovoltaic panels. By utilizing forecasts to guide the converter, we are paving the way for a future where solar energy shines brighter than ever. [ABSTRACT FROM AUTHOR]

Simple Summary: This multicenter study (n = 1133, inclusion criteria: 3.5 cm maximum tumor size and preoperative indication for a boost) provides detailed data on acute and long-term toxicities in breast cancer patients undergoing breast-conserving surgery combined with an anticipated intraoperative boost with low-energy X-rays followed by whole breast irradiation. Toxicity assessments, based on LENT SOMA criteria, were performed annually up to 10 years of follow-up. IORT boost was completed in 90% and EBRT in 97% of cases. No grade 3 or 4 acute toxicities were observed, with mild acute side effects reported in a small proportion of patients. Chronic toxicities were seen in 16.2% of patients with teleangiectasia, 14.3% with grade ≥ 2 fibrosis, 3.4% with grade ≥ 2 pain, and 1.1% with hyperpigmentation. The results show that the therapy is safe and feasible in terms of toxicity and confirms intraoperative boost as a standard method of boost application in a large prospective cohort. In the context of breast cancer treatment optimization, this study prospectively examines the feasibility and outcomes of utilizing intraoperative radiotherapy (IORT) as a boost in combination with standard external beam radiotherapy (EBRT) for high-risk patients. Different guidelines recommend such a tumor bed boost in addition to whole breast irradiation with EBRT for patients with risk factors for local breast cancer recurrence. The TARGIT BQR (NCT01440010) is a prospective, multicenter registry study aimed at ensuring the quality of clinical outcomes. It provides, for the first time, data from a large cohort with a detailed assessment of acute and long-term toxicity following an IORT boost using low-energy X-rays. Inclusion criteria encompassed tumors up to 3.5 cm in size and preoperative indications for a boost. The IORT boost, administered immediately after tumor resection, delivered a single dose of 20 Gy. EBRT and systemic therapy adhered to local tumor board recommendations. Follow-up for toxicity assessment (LENT SOMA criteria: fibrosis, teleangiectasia, retraction, pain, breast edema, lymphedema, hyperpigmentation, ulceration) took place before surgery, 6 weeks to 90 days after EBRT, 6 months after IORT, and then annually using standardized case report forms (CRFs). Between 2011 and 2020, 1133 patients from 10 centers were preoperatively enrolled. The planned IORT boost was conducted in 90%, and EBRT in 97% of cases. Median follow-up was 32 months (range 1–120, 20.4% dropped out), with a median age of 61 years (range 30–90). No acute grade 3 or 4 toxicities were observed. Acute side effects included erythema grade 1 or 2 in 4.4%, palpable seroma in 9.1%, punctured seroma in 0.3%, and wound healing disorders in 2.1%. Overall, chronic teleangiectasia of any grade occurred in 16.2%, fibrosis grade ≥ 2 in 14.3%, pain grade ≥ 2 in 3.4%, and hyperpigmentation in 1.1%. In conclusion, a tumor bed boost through IORT using low-energy X-rays is a swift and feasible method that demonstrates low rates in terms of acute or long-term toxicity profiles in combination with whole breast irradiation. [ABSTRACT FROM AUTHOR]

Simple Summary: The aim of the present study is to assess, for the first time, the feasibility and safety of combining photon IORT with ultrahypofractionated WBI after breast-conserving surgery (BCS). From July 2020 to December 2022, seventy-two patients diagnosed with low-risk early BC were included in this prospective study. IORT was administered at a dose of 20 Gy to the surface's applicator, and WBI was to be administered 3–5 weeks after surgery at a total dose of 26 Gy in five consecutive days. All patients completed the proposed treatment schedule, and no severe acute or late grade 3 toxicity was observed at 3 and 12 months after WBI, respectively. Our results confirm, for the first time, that the combination of ultrafractionation WBI after BCS and photon-IORT is a feasible and safe option in patients with early BC. Background: The current standard of local treatment for patients with localized breast cancer (BC) includes whole breast irradiation (WBI) after breast-conserving surgery (BCS). Ultrahypofractionated WBI schemes (1-week treatment) were shown not to be inferior to the standard WBI. Tumor bed boost using photon intraoperative radiotherapy (IORT) is safe and feasible in combination with standard WBI. The aim of the present study is to assess, for the first time, the feasibility and safety of combining photon IORT with ultrahypofractionated WBI. Methods: Patients diagnosed with low-risk early BC candidates for BCS were included in this prospective study. IORT was administered at a dose of 20 Gy to the surface's applicator, and WBI was administered 3–5 weeks after surgery at a total dose of 26 Gy in five consecutive days. Results: From July 2020 to December 2022, seventy-two patients diagnosed with low-risk early BC and treated in our institution were included in this prospective study. All patients completed the proposed treatment, and no severe acute or late grade 3 toxicity was observed 3 and 12 months after WBI, respectively. Conclusions: Our results confirm for the first time that the combination of ultrafractionation WBI and photon-IORT after BCS is a feasible and safe option in patients with early BC. [ABSTRACT FROM AUTHOR]

Simple Summary: Current guidelines recommend treatment planning using [18F]FDG-PET/CT for the management of advanced cervical cancer, where suspicious lymph nodes may be treated with nodal boosting, extended-field radiotherapy, and/or debulking in addition to standard chemoradiotherapy to improve survival. However, caution must be exercised because of the risk of unnecessary therapy-related toxicity due to the overtreatment of false-positive nodes. Despite this daily dilemma in clinical practice, only a few studies have evaluated the management of [18F]FDG-positive nodes. Therefore, this study aimed to assess how often [18F]FDG-PET/CT lymph node information is used in the management of advanced-stage cervical cancer. We found that a total of 380/434 patients (88%) received interventions targeting [18F]FDG-positive nodes, with the following distribution: nodal boosting (84%), extended-field radiotherapy (78%), and debulking (12%). Despite existing guidelines advocating [18F]FDG-PET/CT-guided treatment planning for the management of advanced cervical cancer, this study highlights that not all cases of [18F]FDG-positive nodes received an intervention. Background: Modern treatment guidelines for women with advanced cervical cancer recommend staging using 2-deoxy-2-[18F]fluoro-D-glucose positron emission computed tomography ([18F]FDG-PET/CT). However, the risk of false-positive nodes and therapy-related adverse events requires caution in treatment planning. Using data from the Netherlands Cancer Registry (NCR), we estimated the impact of [18F]FDG-PET/CT on treatment management in women with locally advanced cervical cancer, i.e., on nodal boosting, field extension, and/or debulking in cases of suspected lymph nodes. Methods: Women diagnosed between 2009 and 2017, who received chemoradiotherapy for International Federation of Gynaecology and Obstetrics (2009) stage IB2, IIA2-IVB cervical cancer with an [18F]FDG-positive node, were retrospectively selected from the NCR database. Patients with pathological nodal examination before treatment were excluded. The frequency of nodal boosting, extended-field radiotherapy, and debulking procedures applied to patients with [18F]FDG-positive lymph nodes was evaluated. Results: Among the 434 eligible patients with [18F]FDG-positive nodes, 380 (88%) received interventions targeting these lymph nodes: 84% of these 380 patients received nodal boosting, 78% extended-field radiotherapy, and 12% debulking surgery. [18F]FDG-positive nodes in patients receiving these treatments were more likely to be classified as suspicious than inconclusive (p = 0.009), located in the para-aortic region (p < 0.001), and larger (p < 0.001) than in patients who did not receive these treatments. Conclusion: While existing guidelines advocate [18F]FDG-PET/CT-guided treatment planning for the management of advanced cervical cancer, this study highlights that not all cases of [18F]FDG-positive nodes received an intervention, possibly due to the risk of false-positive results. Improvement of nodal staging may reduce suboptimal treatment planning. [ABSTRACT FROM AUTHOR]

A single-phase bidirectional DC/DC battery charger with a P&O MPPT current control strategy for a standalone energy management system has been integrated with an interleaved switched capacitor DC/AC inverter with an RMS feedback phase-shifted unipolar sinusoidal PWM control strategy. In the published literature, P&O MPPT control is used to drive a boost converter connected in parallel to a battery charger; this modified strategy combines a P&O MPPT algorithm with current control to drive an interleaving buck-boost battery charger. This battery charger circuit is connected in parallel to a closed loop controlled interleaved inverter that feeds the AC home load. MATLAB/Simulink based simulation circuit was developed and used to validate the successful integration of the interleaved battery charger with the global system. To do this, the system is tested with varying input conditions of irradiance and temperature. The system's response to these variable inputs is monitored and analysed. The simulation results show the proposed method is effective for standalone battery-based PV systems. The system provides a more efficient and faster response compared with both an interleaved and non-interleaved voltage-controlled battery charger circuit that is also integrated with the global system. This battery charger control strategy is also shown to protect the battery from over-charging as well as discharging below 25%, which can improve and protect the long-term battery performance. Compared with novel industry approaches, the proposed system is simpler by nature due to the reduced number of conversions and therefore a reduced number of components which provides economic advantages. [ABSTRACT FROM AUTHOR]

This study aims to determine how the global media covered the Padma Bridge inauguration news and its contribution to achieving the SDGs (Sustainable Development Goals) of Bangladesh. After overcoming several obstacles, Bengalis' desire to use their own money is set to become a reality. In this study, both qualitative and quantitative methods were used. The first stage was using convenience the sampling method to gather information on the Padma Multipurpose Bridge's opening, from 25 June to 25 July 2022, from the usual worldwide media and TV networks. The information coverage of several news sources from various countries was subsequently investigated utilizing the content analysis approach. In one way, newspaper stories, expert comments, research papers on the Padma Bridge, government reports, the Bangladesh Planning commission, and finance ministry records have all been analysed to collect the Padma Bridge's role in fulfilling SDGs. The data show that the Padma Bridge, which showcases Bangladesh's financial potential, is given significant weight in the international media. The Padma Bridge will contribute to a 29% increase in Bangladesh's development industry, a 9.5% increase in agricultural output, an 8% increase in the industrial and transportation sectors, and a 0.84% annual decrease in poverty. By the year 2041, Bangladesh hopes to be a prosperous, ecologically friendly, and socially inclusive monarchy. The Padma Bridge will facilitate the development of new rail networks, improve connectivity, and expand global trade. Through this bridge, the enhancement of people's lifestyles and subsistence abilities is made possible in a significant way. [ABSTRACT FROM AUTHOR]

Simple Summary: Brachytherapy for prostate cancer is a method where radiotherapy is directly delivered to the prostate via surgical insertion of the radioactive source. Brachytherapy can increase the amount of radiation delivered to the prostate cancer but sometimes at the cost of increased side effects. Here, we review promising early results from alternative non-invasive techniques that now exist and can deliver similar radiotherapy doses without the need for the surgical procedure required for brachytherapy. Prostate cancer (PC) is the most common malignancy in men. Internal radiotherapy (brachytherapy) has been used to treat PC successfully for over a century. In particular, there is level-one evidence of the benefits of using brachytherapy to escalate the dose of radiotherapy compared with standard external beam radiotherapy approaches. However, the use of PC brachytherapy is declining, despite strong evidence for its improved cancer outcomes. A method using external beam radiotherapy known as virtual high-dose-rate brachytherapy boost (vHDRB) aims to noninvasively mimic a brachytherapy boost radiation dose plan. In this review, we consider the evidence supporting brachytherapy boosts for PC and the continuing evolution of vHDRB approaches, culminating in the current generation of clinical trials, which will help define the role of this emerging modality. [ABSTRACT FROM AUTHOR]

Simple Summary: Radiotherapy plays an important role in the multidisciplinary management of breast cancer. Historically, techniques for radiation treatment of breast carcinomas have been based upon two-dimensional planning and dose application. This treatment has been associated with a relatively high risk of chronic toxicity. Modern radiotherapy techniques have made it possible to achieve a better target volume coverage with a lower critical organ radiation burden. New fractionation methods have led to shorter treatment times while improving the therapeutic ratio. All of this has permitted a reduction in both acute and chronic toxicity, and led to improvements in treatment effectiveness. Currently, partial breast irradiation is used effectively in indicated cases. This can be achieved through utilizing various irradiation techniques and a number of fractionation schemes (e.g., partial breast irradiation and accelerated partial breast irradiation). Problematic issues are related to the application of adjuvant radiotherapy in patients immediately after breast replacement surgery. Modern radiotherapy techniques are designed to permit reduced irradiation of healthy tissue, resulting in a diminished risk of adverse effects and shortened recovery times. Several randomized studies have demonstrated the benefits of increased dosage to the tumor bed area in combination with whole breast irradiation (WBI). Conventional WBI treatment following breast-conserving procedures, which required 5–7 weeks of daily treatments, has been reduced to 3–4 weeks when using hyperfractionated regimens. The dosage administration improves local control, albeit with poorer cosmesis. The method of accelerated partial breast irradiation (APBI) shortens the treatment period whilst reducing the irradiated volume. APBI can be delivered using intraoperative radiation, brachytherapy, or external beam radiotherapy. Currently available data support the use of external beam partial breast irradiation in selected patients. Modern radiotherapy techniques make it possible to achieve favorable cosmesis in most patients undergoing immediate breast reconstruction surgery, and studies confirm that current methods of external beam radiation allow an acceptable coverage of target volumes both in the reconstructed breast and in the regional lymphatic nodes. [ABSTRACT FROM AUTHOR]

Simple Summary: The benefit of administering an extra dose to the tumor bed (boost) prior or simultaneously to adjuvant breast radiotherapy in terms of local recurrence rate has already been the subject of several studies and, thus, has already found justification in appropriate patient cases. In this study, we compared two boost techniques, an intraoperative radiotherapy (IORT) boost and an intensity-modulated radiotherapy boost (IMRT), analyzing two patient collectives to determine the equivalence of the two techniques or which of the two proves superior. According to our monocenter data on tumor control, survival rates, toxicities, and cosmetic results, no significant differences were revealed between the two boost techniques, and it cannot be generalized that one technique is more advantageous than the other. The aim of this retrospective study is to compare the two boost subgroups, IORT or IMRT, in terms of overall survival (OS), progression-free survival (PFS), cosmesis, and acute and late toxicity. It shall be shown whether and which of the boost techniques offers better results with respect to the facial points, since there are already many studies on applying boost to the tumor bed after/during breast conserving surgery, and there are few which compare the different techniques. For this comparison, two subgroups of 76 patients each (n = 152), treated between 2002 and 2015, were enrolled in the study. In one subgroup, the 9 Gy boost was intraoperatively administered after complete removal of the primary tumor, while the other subgroup received the boost of 8.4 Gy percutaneously and simultaneously integrated into the tumor bed after breast conserving surgery. Both subgroups have subsequently undergone whole breast irradiation (WBI) of 50.4/50 Gy in 1.8–2 Gy per fraction. OS and the incidence of late toxicity did not differ between the two subgroups and no risk factor was found regarding PFS. Acute toxicities initially occurred significantly less (p < 0.001) in the IORT subgroup; however, after WBI took place, this difference vanished. Therefore, boost application by means of IORT or IMRT can be considered equivalent. [ABSTRACT FROM AUTHOR]

This paper presents a triple-mode average current control (TACC) strategy to achieve unity power factor and reduce the current stress for a boost PFC converter. The controller switches among different modes in each half-line cycle, and smooth transition is ensured by mapping of the operation region. By adaptive mode shifting, it reduces the current stress and current distortion caused by non-linear effects. With valley current shaping and comparisons, the TACC controller accordingly incorporates three control laws to adapt different modes. In discontinuous conduction mode (DCM), a variable on-time is calculated while the modulation is equivalent to PWM. In critical conduction mode (CRM), a constant on-time is derived, while the switching cycle is modified to regulate the current average value. For both DCM and CRM, the switching cycle is slightly extended to realize valley switching. Furthermore, with valley current shaping, the proposed controller reuses the CRM calculation to form continuous conduction mode (CCM) control law. To make the control laws compatible, normalized mapping and design rules are provided with respect to mode boundaries. This allows the TACC controller to automatically switch among different modes. Finally, experimental results prove the effectiveness of the controller in reducing the current stress and enlarging the preferable power range. [ABSTRACT FROM AUTHOR]

Simple Summary: Intraoperative electron radiation therapy (IOERT) has repeatedly demonstrated its power to yield high local control rates in all risk constellation of patients with invasive breast cancer when given as tumor bed boost prior to conventional whole breast irradiation (WBI) after breast conserving surgery (BCS). Since the standard for WBI continuously moved towards hypofractionation, we initiated a prospective trial in 2011 where we combined a high precision IOERT boost with a "moderate" hypofractionation schedule (15 × 2.7 Gy), the HIOB-trial [NCT01343459], as clinical evidence for this combination was scarce. Our results demonstrated a low five-year local recurrence rate (overall two events in a population of 1119 patients), which undershot such best evidences in two age groups (41–50 y and >50 y). As acute and late toxicity were mild with no impaired cosmetic outcome, the HIOB-concept seems to be a viable treatment option for patients who underwent BCS and intended WBI. Background and purpose: To investigate intraoperative electron radiation therapy (IOERT) as a tumor bed boost during breast conserving surgery (BCS) followed by hypofractionated whole breast irradiation (HWBI) on age-correlated in-breast recurrence (IBR) rates in patients with low- to high-risk invasive breast cancer. Material and methods: BCS and IOERT (11.1 Gy) preceded a HWBI (40.5 Gy) in 15 fractions. Five-year IBR-rates were compared by a sequential ratio test (SQRT) with best evidences in three age groups (35–40 y and 41–50 y: 3.6%, >50 y: 2%) in a prospective single arm design. Null hypothesis (H0) was defined to undershoot these benchmarks for proof of superiority. Results: Of 1445 enrolled patients, 326 met exclusion criteria, leaving 1119 as eligible for analysis. After a median follow-up of 50 months (range 0.7–104), we detected two local recurrences, both in the age group >50 y. With no observed IBR, superiority was demonstrated for the patient groups 41–50 and >50 y, respectively. For the youngest group (35–40 y), no appropriate statistical evaluation was yet possible due to insufficient recruitment. Conclusions: In terms of five-year IBR-rates, Boost-IOERT followed by HWBI has been demonstrated to be superior in patients older than 50 and in the age group 41–50 when compared to best published evidence until 2010. [ABSTRACT FROM AUTHOR]

Modern radiotherapy techniques are designed to permit reduced irradiation of healthy tissue, resulting in a diminished risk of adverse effects and shortened recovery times. Several randomized studies have demonstrated the benefits of increased dosage to the tumor bed area in combination with whole breast irradiation (WBI). Conventional WBI treatment following breast-conserving procedures, which required 5-7 weeks of daily treatments, has been reduced to 3-4 weeks when using hyperfractionated regimens. The dosage administration improves local control, albeit with poorer cosmesis. The method of accelerated partial breast irradiation (APBI) shortens the treatment period whilst reducing the irradiated volume. APBI can be delivered using intraoperative radiation, brachytherapy, or external beam radiotherapy. Currently available data support the use of external beam partial breast irradiation in selected patients. Modern radiotherapy techniques make it possible to achieve favorable cosmesis in most patients undergoing immediate breast reconstruction surgery, and studies confirm that current methods of external beam radiation allow an acceptable coverage of target volumes both in the reconstructed breast and in the regional lymphatic nodes.

In this paper, in order to achieve zero ripple conditions, the use of a ripple mirror (RM) circuit for the boost converter is proposed. The operation modes are studied and steady-state analyses performed to show the merits of the proposed converter. It is found that the proposed RM circuit technique can provide much better flexibility than the two-phase interleaved boost converter for locating the zero ripple operating point in the design stage. In addition, the choice of using a boundary-mode control is mainly based on the consideration of achieving both ZVS (zero voltage switching)/ZCS (zero current switching) soft-switching and constant on-time control for the converter. To verify the performance of the proposed converter, a 48 V input and 200 W/200 V output prototype is constructed. Experimental results verify the effectiveness of the proposed converter. [ABSTRACT FROM AUTHOR]

Vaccination is one of the key strategies to stop the COVID-19 pandemic. This review aims to evaluate the current state of vaccine development and to determine the issues that merit additional research. We conducted a literature review of the development of COVID-19 vaccines, their effectiveness, and their use in special patient groups. To date, 140 vaccines are in clinical development. Vector, RNA, subunit, and inactivated vaccines, as well as DNA vaccines, have been approved for human use. Vector vaccines have been well studied prior to the COVID-19 pandemic; however, their long-term efficacy and approaches to scaling up their production remain questionable. The main challenge for RNA vaccines is to improve their stability during production, storage, and transportation. For inactivated vaccines, the key issue is to improve their immunogenicity and effectiveness. To date, it has been shown that the immunogenicity of COVID-19 vaccines directly correlates with their clinical efficacy. In view of the constant mutation, the emerging new SARS-CoV-2 variants have been shown to be able to partially escape post-vaccination immune response; however, most vaccines remain sufficiently effective regardless of the variant of the virus. One of the promising strategies to improve the effectiveness of vaccination, which is being studied, is the use of different platforms within a single vaccination course. Despite significant progress in the development and study of COVID-19 vaccines, there are many issues that require further research. [ABSTRACT FROM AUTHOR]

This paper describes an improved non-linear switching circuit (INLSC) for active rectification of voltage and reduction of ripples in the voltage waveform for the piezoelectric energy harvesting (PEH) system. The proposed converter controls the alternating current (AC) generated by the piezoelectric device (PD) under mechanical vibration. The proposed circuit combines the boost and buck-boost processes through a switching process, which functions in both positive and negative cycles. In addition, it controls the voltage and frequency of the load capacitor. In this process, the passive components in the circuit are energised by being short with the AC voltage using switching signals, which facilitates the active rectification of ultra-low AC voltage. Design considerations, theoretical analysis, simulations and experimental results are presented. It was shown that the circuit was able to control the switching signal and to convert low AC voltage (0.44 Vi) to high direct current (DC) voltage (6.5 Vdc) while achieving an output power of 469 µW which outperforms the existing similar circuits and synchronous rectifier circuit. The ripples in the rectified voltage were also comparatively less. Application-wise, the proposed circuit could power a manually connected 7-segments display, commonly used for traffic applications. [ABSTRACT FROM AUTHOR]

Thermoelectric generators (TEGs) are devices that convert heat into electricity. This paper is about the design of a Maximum Power Point Tracking (MPPT) technique for a TEG module. The module is built using 204 TEGs connected in series. It is connected to the load through a DC/DC boost converter. The MPPT technique used in this work is the Interval Type 2 Fuzzy Logic Controller (IT2FLC). To verify its performance, the IT2FLC is compared with a traditional Perturb and Observe (P&O) MPPT algorithm in the case of power and voltage response at steady state, load switching, and through various ranges of temperature differences (ΔT). The TEG module is modeled and the whole system is simulated successfully using MATLAB SIMULINK R2017a. [ABSTRACT FROM AUTHOR]

The hybrid three-phase rectifiers (HTR) consist of parallel associations of two rectifiers (rectifier 1 and rectifier 2), each one of them with a distinct operation, while the sum of their input currents forms a sinusoidal or multilevel waveform. In general, rectifier 1 is a GRAETZ (full bridge) (can be combined with a BOOST converter) and rectifier 2 is combined with a DC-DC converter. In this HTR contest, this paper is intended to answer some important questions about those hybrid rectifiers. To obtain the correct answers, the study is conducted as an analysis of a systematic literature review. Thus, a search was carried out in the databases, mostly IEEE and IET, and 34 papers were selected as the best corresponding to the HTR theme. It is observed that the preferred form of power distribution in unidirectional hybrid three-phase rectifiers (UHTR) is 55 % P o (rectifier 1) and 45 % P o (rectifier 2). For the bidirectional hybrid three-phase rectifiers (BHTR), rectifier 1 preferably takes 90 %   of   P o and 10 %   of   P o is processed by rectifier 2. It is also observed that the UHTR that employ the single-ended primary-inductor converter (SEPIC) or VIENNA converter topologies in rectifier 2 can present sinusoidal input currents with low total harmonic distortion (THD) and high Power Factor (PF), even successfully complying with the international standards. The same can be said about the rectifier that employs a pulse-width (PWM) converter of BOOST topology in rectifier 2. In short, the HTR are interesting because they allow using the GRAETZ full bridge topology in rectifier 1, thus taking advantage of its characteristics, being simple, robust, and reliable. At the same time, the advantages of rectifier 2, i.e., high PF and low THD, are well used. In addition, this article also points out the future direction of research that is still unexplored in the literature, thus giving opportunities for future innovation. [ABSTRACT FROM AUTHOR]

The constant advance in the development of piezoelectric materials for energy harvesting has demanded new implementations in the electronics field. The piezoelectric property of these materials has been considered an energy source for low-power devices; nevertheless, the units that provide energy are usually adapted to just one piezoelectric device. This aspect complicates the process, taking into account the amount of time needed for an energy harvest; therefore, this research inquired at first into the adequate piezoelectric materials for carrying out the current study. Afterwards, an energy management unit was designed, considering the connection between some modules and allowing the sourcing of an electrolytic cell for producing hydrogen and, in turn, energy. The results evidence a decrease in time charging of the energy storage unit, which allows a cell's supply of energy in shorter time intervals, its design efficiency being about 90%, in such a way that the energy harvested through the piezoelectric devices can be used in a better manner. [ABSTRACT FROM AUTHOR]

The current article presents the design, implementation, validation, and use of a Computer-Aided Control System Design (CACSD) toolbox for nonlinear and hybrid system uncertainty modeling, simulation, and control using μ synthesis. Remarkable features include generalization of classical system interconnection operations to nonlinear and hybrid systems, automatic computation of equilibrium points for nonlinear systems, and optimization of least conservative uncertainty bounds, with direct applicability for μ synthesis. A unified approach is presented for the step-down (buck), step-up (boost), and single-ended primary-inductor (SEPIC) converters to showcase the use and flexibility of the toolbox. Robust controllers were computed by minimization of the H ∞ norm of the augmented performance systems, encompassing a wide range of uncertainty types, and have been designed using the well-known mixed-sensitivity closed loop shaping μ synthesis method. [ABSTRACT FROM AUTHOR]

The implications of boosting Omalizumab treatment (OT) in patients with severe allergic asthma (SAA) remain unclear. The study aimed to explore and compare the 12-month effectiveness between continuous, at least 10-month OT (continuation group) and four-month boost of Omalizumab (boost group) in adult patients with SAA. In this retrospective cohort study, clinical data were collected for further analysis. Of all participants (n = 124), a significant reduction in annual exacerbations (baseline = 0.8 ± 1.5, follow-up = 0.5 ± 1.0, p = 0.047 *) and improvement in small airway ventilation as evaluated by forced expiratory flow at 25–75% (baseline = 55.1 ± 11.1%, follow-up = 59.4 ± 8.4%, p < 0.001 *) were found in the continuation group (n = 110). By contrast, the boost group (n = 14) had significantly increased annual exacerbations (baseline = 0.7 ± 1.4, follow-up = 2.9 ± 3.6, p = 0.031 *) and impaired small airway function (baseline = 55.3 ± 12.9, follow-up = 52.1 ± 12.5, p = 0.026 *). Furthermore, the continuation group rather than the boost group had significant decreases in the frequency of oral corticosteroid (OCS) use as controllers (baseline = 32.7%, follow-up = 20.0%, p = 0.047 *; baseline = 50.0%, follow-up = 21.4%, p = 0.237, respectively) and OCS maintenance dose (mg/month) (baseline = 85.9 ± 180.8, follow-up = 45.8 ± 106.6, p = 0.020 *; baseline = 171.4 ± 221.5, follow-up = 50.0 ± 104.3, p = 0.064, respectively), and increases in asthma control test scores (baseline = 16.0 ± 3.0, follow-up = 19.8 ± 4.4, p < 0.001 *; baseline = 14.6 ± 3.8, follow-up = 19.7 ± 4.7, p = 0.050, respectively). Continuous OT would be beneficial for adult patients with SAA, while boost of Omalizumab would worsen their long-term outcomes. [ABSTRACT FROM AUTHOR]

Many applications (electric vehicles, renewable energies, low-voltage DC grids) require simple, high-power density and low-current ripple-boost converters. Traditional step-up converters are limited when large transformation ratios are involved. In this work is proposed a step-up converter that brings together the characteristics of high gain, low ripple, and high-power density. From the converter proposal, a mathematical analysis of its operation is first performed, including its static transfer function, stress of components, and voltage and current ripples. Furthermore, it provides a design example for an application of Vin = 48 V to Vo = 270 V and 500 W. For its implementation, two different wide bandgap (WBG) semiconductor models have been used, hybrid GaN cascodes and SiC MOSFETs. Finally, the experimental results of the produced prototypes are shown, and the results are discussed. [ABSTRACT FROM AUTHOR]

Project-based learning (PBL) is proposed for the development of a Hardware-in-the-Loop (HIL) platform and the design of its digital controller for an undergraduate course on Digital Electronic Systems. The objective for students is the design of a digitally controlled HIL Boost converter, a digital pulse-width modulator (DPWM) and a current mode controller, implemented in field-programmable gate array (FPGA) devices. To this end, the different parts of the project are developed and evaluated, maximizing the use of FPGA resources in the design of the HIL and DPWM blocks, and applying design techniques that minimize the use of the digital resources used in the design of the controller. Students are equipped with a new individualized educational experience, allowing them to test their technical competence and knowledge in an environment close to the reality of the industry. [ABSTRACT FROM AUTHOR]

This paper proposes a white-box approach for identifying the parameters of DC-DC buck and boost switch mode power converters. It is based on discretizing the differential equations that describe the dynamic behavior of the converters. From the discretized equations and experimental data, the parameters of the converters are identified, thus obtaining both the values of the passive components and the transfer function coefficients of the controller. To this end, steady state and transient experimental signals are analyzed, including the input and output voltages and the inductor and output currents. To determine the accuracy of the proposed method, once the parameters are identified, a simulation with the identified parameters of the converter is run and compared with experimental signals. Such results show the accuracy and feasibility of the approach proposed in this work, which can be extended to other converters and electrical and electronic devices. [ABSTRACT FROM AUTHOR]