Common Mode Research Articles

A Non-Linear Control Technique for Single Phase qZSI

Quasi-Z-source inverters, or qZSIs, are a common type of inverter used in transformer-less systems because they can boost or buck input voltage without a requirement for a DC- DC converter. A transformer is not necessary for the qZSI's single-stage conversion to operate as a grid-tie converter. In transformer-less designs common mode current is the major problem, though, because there is no galvanic isolation. To reduce the common mode current, this article offers controlling the qZSI using a modified pulse width modulation (PWM) approach two additional semiconductor switches. The developed methodology provides a practical means of integrating solar photovoltaic systems into the grid. what the recommended topology's attributes should be: 1)It uses the phase-leg shoot through to boost the direct current and voltage to required level by eliminating the need for a second dc-dc converter. 2) Freewheeling is achieved while removing PWM deadtime by employing extra linked switches.

Radiation influence on planar reconfigurable field effect transistor low noise amplifier performance

Abstract Many novel devices have been proposed in the literature to mitigate the short channel effect and the reconfigurable FET (RFET) is one of them. The circuits based on new devices need to be investigated when they are introduced. This work has two parts: (i) designing cascoded RFET low noise amplifiers (LNA) and their performance analysis; and (ii) single-event performance analysis of RFET-LNAs. The designed LNA has a gain of 12 dB and a noise figure of 2.42 dB. The device in the common gate configuration mode is more susceptible to heavy ion radiation and collects more charge (QC) compared to the device in the common source configuration mode. Through temporal and frequency analysis, the irradiation disturbance is examined. In the temporal analysis, the collected charge (QC) is used as a metric, and the spectrogram is used in the frequency analysis.

A Study on the Psychological Impact on Key Caregivers of Traumatic Brain Injury Versus Non-traumatic Brain Injury in Critically Ill Trauma Patients.

Caregivers of patients admitted in intensive care units may experience acute emotional and psychological stress burden that can manifest as acute psychiatric symptoms and can negatively impact interpersonal relationships and work performance. The aim of this study is to elucidate the socioeconomic burden of trauma and the effect of psychological stress on key caregivers between traumatic brain injury (TBI) and non-TBI patients. The study was conducted on 200 caregivers of critically ill trauma patients admitted to the trauma ICU for at least 48 hours and were divided into two groups: Group 1- Patients with TBI with Trauma ICU admission of more than 48 hours and Group 2- Non-TBI patients (chest trauma, abdominal trauma, etc.) with Trauma ICU admission of more than 48 hours. The key caregivers in two groups were subjected to Critical Care Family Need Inventory (CCFNI) and to National Stressful Events Survey Acute Stress Disorder Short Scale (NSESSS) to measure the needs and severity of acute stress symptoms respectively) at 48 hours of ICU admission, day seven, day 15, and day 30 (follow-up). The statistical analysis was performed using SPSSv23 (IBM Corp., Armonk, NY, USA). Motor vehicle collision was the most common mode of injury among patients in both groups. The sociodemographic parameters of the caregivers were comparable in both groups. Predominantly the patients were males while key caregivers were females. In Group 1 caregivers experienced higher family burden and severe psychological distress at ICU. At the time of admission, needs of caregivers in all the domains (support, comfort, information, accessibility and reassurance) were comparable in both groups. On day seven, the needs for information, accessibility, and reassurance in the TBI group were significantly higher than in the non-TBI group (p<0.01). On day 15, the needs for support, information, accessibility, and reassurance in the TBI group were significantly higher than in the non-TBI group (p≤0.001). On day 30, the needs for support, information, accessibility, and reassurance in the TBI group were significantly higher than in the non-TBI group (p<0.001) but need for comfort was higher in the non-TBI group (p<0.05).Caregivers of patients with TBI had higher stress burden and higher NSESSS than that of non-TBI (p<0.05). We concluded that key caregivers of patients with TBI have a high stress burden, highlighting the importance of providing psychological support to this group.

Engineered Tendon-Fibrocartilage-Bone Composite With Mechanical Stimulation for Augmentation of Rotator Cuff Repair: A Study Using an In Vivo Canine Model With a 6-Month Follow-up

Background: Rotator cuff repair augmentation using biological materials has become popular in clinical practice to reduce the high retear rates associated with traditional repair techniques. Tissue engineering approaches, such as engineered tendon-fibrocartilage-bone composite (TFBC), have shown promise in enhancing the biological healing of rotator cuff tears in animals. However, previous studies have provided limited long-term data on TFBC repair outcomes. The effect of mechanical stimulation on TFBC has not been explored extensively. Purpose: To evaluate functional outcomes after rotator cuff repair with engineered TFBC subjected to mechanical stimulation in a 6-month follow-up using a canine in vivo model. Study Design: Controlled laboratory study. Methods: A total of 40 canines with an acute infraspinatus (ISP) tendon transection model were randomly allocated to 4 groups (n =10): (1) unilateral ISP tendon undergoing suture repair only (control surgery); (2) augmentation with engineered TFBC alone (TFBC); (3) augmentation with engineered TFBC and bone marrow-derived stem cells (BMSCs) (TFBC+C); and (4) augmentation with engineered TFBC and BMSCs, as well as mechanical stimulation (TFBC+C+M). Outcome measures—including biomechanical evaluations such as failure strength, stiffness, failure mode, gross appearance, ISP tendon and muscle morphological assessment, and histological analysis—were performed 6 months after surgery. Results: As shown in the mechanical test, the TFBC+C+M group exhibited higher failure strength compared with other repair techniques. The most common failure mode was avulsion fracture in the TFBC+C+M group, but tendon-bone junction rupture was observed predominantly in different groups. Engineered TFBC with mechanical stimulation showed over 70% relative failure strength compared with normal ISP, and the other groups showed about 50% relative failure strength. Histological analysis revealed less fat infiltration and closer-to-normal muscle fiber structure in the mechanical stimulation group. Conclusion: This study provides evidence that mechanical stimulation of engineered TFBC promotes rotator cuff regeneration, thus supporting its potential for rotator cuff repair augmentation. Clinical Relevance: This study provides valuable evidence supporting the use of a novel tissue-engineered material (TFBC) in rotator cuff repair and paves the way for advancements in the field of rotator cuff regeneration.

The three YTHDF paralogs and VIRMA are strong cross-histotype tumor driver candidates among m6A core genes.

N6-Methyladenosine (m6A) is the most abundant internal modification in mRNAs. Despite accumulating evidence for the profound impact of m6A on cancer biology, there are conflicting reports that alterations in genes encoding the m6A machinery proteins can either promote or suppress cancer, even in the same tumor type. Using data from The Cancer Genome Atlas, we performed a pan-cancer investigation of 15 m6A core factors in nearly 10000 samples from 31 tumor types to reveal underlying cross-tumor patterns. Altered expression, largely driven by copy number variations at the chromosome arm level, results in the most common mode of dysregulation of these factors. YTHDF1, YTHDF2, YTHDF3and VIRMA are the most frequently altered factors and the only ones to be uniquely altered when tumors are grouped according to the expression pattern of the m6A factors. These genes are also the only ones with coherent, pan-cancer predictive power for progression-free survival. On the contrary, METTL3, the most intensively studied m6A factor as a cancer target, shows much lower levels of alteration and no predictive power for patient survival. Therefore, we propose the non-enzymatic YTHDF and VIRMA genes as preferred subjects to dissect the role of m6A in cancer and as priority cancer targets.

Isoform-specific C-terminal phosphorylation drives autoinhibition of Casein kinase 1

Casein kinase 1δ (CK1δ) controls essential biological processes including circadian rhythms and wingless-related integration site (Wnt) signaling, but how its activity is regulated is not well understood. CK1δ is inhibited by autophosphorylation of its intrinsically disordered C-terminal tail. Two CK1 splice variants, δ1 and δ2, are known to have very different effects on circadian rhythms. These variants differ only in the last 16 residues of the tail, referred to as the extreme C termini (XCT), but with marked changes in potential phosphorylation sites. Here, we test whether the XCT of these variants have different effects in autoinhibition of the kinase. Using NMR and hydrogen/deuterium exchange mass spectrometry, we show that the δ1 XCT is preferentially phosphorylated by the kinase and the δ1 tail makes more extensive interactions across the kinase domain. Mutation of δ1-specific XCT phosphorylation sites increases kinase activity both in vitro and in cells and leads to changes in the circadian period, similar to what is reported in vivo. Mechanistically, loss of the phosphorylation sites in XCT disrupts tail interaction with the kinase domain. δ1 autoinhibition relies on conserved anion-binding sites around the CK1 active site, demonstrating a common mode of product inhibition of CK1δ. These findings demonstrate how a phosphorylation cycle controls the activity of this essential kinase.

Multicore fiber design housing a fluorine-doped low-latency core and cutoff shifted cores

Design of heterogeneous 4-core fiber housing a low-latency core and conventional cutoff shifted cores in a standard 125-μm cladding diameter is investigated to enable signal processing delay reduction using common mode impairment. For the low-latency core, 1-μs propagation delay reduction and an optical signal-to-noise ratio (OSNR) comparable to or greater than that of cutoff shifted cores are required. In this paper, we consider an F-doped core and depressed cladding structure with a large effective area as the low-latency core. It can be expected to achieve sufficient group delay reduction of the low-latency core, the OSNR unification among heterogeneous cores, and low inter-core crosstalk in a standard 125-μm cladding diameter. Consequently, we revealed the optimized low-latency core achieving the group delay reduction of 1 μs and the OSNR as same level as the cutoff shifted cores as we expected. The designed heterogeneous 4-core fiber with the standard 125-μm cladding diameter suppressed the inter-core crosstalk to be low enough to support a 1,000-km long transmission. We expect the figure-of-merit (FoM) of the 4-core fiber to be as high as previously reported 4-core fibers, and the FoM improvement are found when the low latency core and cutoff shifted core are placed alternately thanks to the core heterogeneity.

Common Mode and Terminal Voltages With Effect of Device Junction Capacitance in Five-Level Transformerless PV Inverter

Common Mode and Terminal Voltages With Effect of Device Junction Capacitance in Five-Level Transformerless PV Inverter

Survival and Patterns of Relapse of Cutaneous Squamous Cell Carcinoma With Large Nerve Perineural Spread After Skull Base Surgery and/or Radiation Therapy

The aim of our study was to evaluate survival and patterns of relapse for patients with perineural spread (PNS) of cutaneous squamous cell carcinoma (cSCC), who have undergone curative intent skull base surgery and/or radiation therapy. In addition, we modified the classification of zone 2 disease into 2a and 2b and reported the respective outcome. A review of a prospective database of patients who received diagnoses of PNS of cSCC and were treated with curative intent skull base surgery and/or radiation therapy between the years of 2013 and 2020 was conducted. Kaplan-Meier methods were used to estimate relapse-free survival (RFS), disease-specific survival (DSS), and overall survival (OS). Cox proportional hazard modeling was performed to test associations between patient factors and survival outcomes. Eighty patients with a median follow-up of 36 months were included in the study. The 5-year RFS was 61% (95% CI, 48%-71%), the DSS was 77% (95% CI, 63%-86%), and OS was 67% (95% CI, 53%-78%). In multivariable modeling, involvement of 2 or more nerves was strongly associated with worse 5-year RFS (HR, 4.0; P ≤ .001), DSS (HR, 4.5; P = .004), and OS (HR, 4.3; P = .002). Age group (≥65 years) (HR, 5.1; P = .010) and immune compromise (HR, 10.7; P = .001) were strongly associated with worse OS but not DSS or RFS. The majority of relapses (60%) occurred at the local skin sites. Our study demonstrated surgery followed by radiation therapy was safe and effective in the management of cSCC with PNS. We did not detect a difference in outcome between zones 2a and 2b though further study is required. The most common mode of relapse was at the skin epidermis and/or adjacent dermis highlighting the importance of adequate local skin dose delivery.

A Modified Carrier-Based PWM Strategy for Common Mode Voltage Elimination and Neutral Point Voltage Balance in a Unidirectional Three-Level Converter for AC Motor Drives

A Modified Carrier-Based PWM Strategy for Common Mode Voltage Elimination and Neutral Point Voltage Balance in a Unidirectional Three-Level Converter for AC Motor Drives

Prongs or Mask for Nasal Continuous Positive Airway Pressure in Neonates: Which One Is More Comfortable?

Nasal continuous positive airway pressure (NCPAP) is a common mode of respiratory support in neonatal intensive care units. Our objective was to compare whether NCPAP given with nasal prongs compared with a nasal mask reduces the pain scores in preterm infants with respiratory distress. Preterm infants on NCPAP due to respiratory distress were included in the study. All infants received NCPAP via the Infant Flow SiPAP. The COVERS pain scale was used to score the infants' pain. Each infant was studied alternating between nasal prongs and a nasal mask. Heart rate, respiratory rate, oxygen saturation, and transcutaneous CO 2 (tcCO 2 ) were monitored. Blood pressure and the infants' pain scores were determined every 30 minutes and the average of measurements was taken. The median (interquartile range) values of pain scores, respiratory rates, oxygen saturations, tcCO 2 levels, and systolic blood pressures differed significantly and favored the nasal mask. This study demonstrates that continuous positive airway pressure via a nasal mask leads to a significant reduction in pain scores without altering the respiratory parameters of babies. On the basis of this study, it is possible to conclude that NCPAP applied via nasal mask may be a good alternative to NCPAP applied via nasal prongs.

Digital Active EMI Filter for Smart Electronic Power Converters

Electronic power converters are widespread and crucial components in modern energy scenarios. Beyond mere electrical energy conversion, their electronic structure allows several functionalities to be naturally embedded in them, including energy management, diagnosis, communication, etc. The operation of the converter itself, or the system interfaced by the same, commonly produces undesired electromagnetic interferences (EMIs) that should comply with prescribed limits. This paper presents a digital active EMI filter designed to mitigate such disturbances. The proposed hardware implementation can acquire and analyze the common-mode (CM) noise affecting the circuit and inject a compensation signal to attenuate the measured interference. A novel adaptive algorithm is introduced to compute the necessary signals for effective noise cancellation. The implementation is integrated within a single printed circuit board interfaced with a field-programmable gate array (FPGA) running the control algorithm. The digital filter’s efficacy in EMI reduction is demonstrated using a synchronous buck converter with gallium nitride (GaN) power devices, achieving significant noise reduction. Additionally, potential functionalities are envisioned to fully exploit the capabilities of the proposal beyond EMI filtering, like fault detection, predictive maintenance, smart converter optimization, and communication.

Management of Compound Depressed Fractures over Venous Sinuses

Abstract Objective The aim of this study was to report our experience in the surgical treatment of compound depressed fractures over the venous sinuses with special highlights on the prediction and dealing with intraoperative sinus injury. Materials and Methods We conducted a retrospective review of all patients who underwent surgery for compound depressed fractures overlying the dural venous sinuses in our hospital between January 2019 and December 2021. Results A total of 34 patients were included in our study. The mean age of the patients was 19.85 years, most of our patients were males 27 (79.4%), and isolated head trauma was the most common mode of trauma (76.5%). The superior sagittal sinus (SSS) was distinguished as the most commonly involved venous sinus below the fractures in 28 patients (82.4%). An intraoperative tear in the sinus was found in 17 patients (50%), which was easily controlled with different methods. In two patients who had a severe head injury with a Glasgow Coma Scale (GCS) score of ≤8 associated with a fissure fracture crossing the sinus, there was a complete tear of the sinus followed by massive bleeding, which required sinus ligation. We lost both of them in following days. Conclusion In experienced tertiary neurotrauma centers, compound depressed fractures over the venous sinuses should be surgically elevated in most cases, taking into consideration that bleeding from the sinus can be controlled in most cases, and complete tear of the sinus with massive bleeding is the least scenario faced in reality and is usually associated with a severe head injury. If expert opinion favors the conservative approach, then close follow-up for months is recommended due to the high possibility of sinus thrombosis and intracranial hypertension, especially in children.

On the Consistency of Stochastic Noise Properties and Velocity Estimations from Different Analysis Strategies and Centers with Environmental Loading and CME Corrections

The analysis of the Global NFavigation Satellite System (GNSS) time series provides valuable information for geodesy and geodynamics researcFh. Precise data analysis strategies are crucial for accurately obtaining the linear velocity of GNSS stations, enabling high-precision applications of GNSS time series. This study investigates the impact of different stochastic noise models on velocity estimations derived from GNSS time series, specifically under conditions of environmental loading correction and common mode error (CME) removal. By comparing data from various data centers, we find that post-correction, different analysis strategies exhibit high consistency in their noise characteristics and velocity estimation results. Across various analysis strategies, the optimal noise models were predominantly Power Law with White Noise (PLWN) and Fractional Noise with White Noise (FNWN), with the optimal noise models including COMB/JPL, COMB/SOPAC, and COMB/NGL for approximately 50% of the datasets. Most of the stations (approximately 80%) showed velocity differences below 0.3 mm/year and velocity estimation uncertainties below 0.1 mm/year. Nonetheless, variations in amplitudes and periodic signals persisted due to differences in the processing of raw GNSS observations. For instance, the NGL and JPL datasets, which were processed using GipsyX 2.1 software, showed higher amplitudes of the 5.5-day periodic signal. These findings provide a solid empirical foundation for advancing data analysis methods and enhancing the reliability of GNSS time series results in future research.

Seroprevalence of hepatitis B and hepatitis C virus among clinically suspected cases of viral hepatitis visiting Guhalla Primary Hospital, Northwest Ethiopia

Hepatitis B virus and hepatitis C virus remains one of the leading causes of morbidity and mortality worldwide, particularly in countries with limited resources. The two hepatotropic viruses have common mode of transmission. Hepatitis B virus and hepatitis C virus are the main causes of Cirrhosis, liver cancer and death. To determine the Seroprevalence of HBsAg and anti-HCV antibodies among clinically suspected cases of viral hepatitis visiting Guhalla Primary Hospital, Northwest Ethiopia. A hospital-based retrospective study was conducted at Guhalla Primary Hospital, Northwest Ethiopia. The study included serology registration logbook data from all patients who visited the hospital and were tested using a rapid test kit between September 1st, 2017 to August 30, 2021. Data were entered, cleaned, and analyzed using SPSS version 26 software. Bivariate analysis was computed and a multivariable analysis was conducted to provide an adjusted odds ratio (AOR). p-value < 0.05 at a 95% confidence interval was considered statistically significant. In this study, a total of 883(883 for HBV and 366 for HCV) study participants were included. The overall prevalence of HBsAg and anti-HCV were 124/883(14%) and 73/366 (19.9%), respectively. The prevalence of HBV and HCV among males from the total HBV and HCV screened was 70/410 (17.1%) and 53/366(14.4%) respectively. In this study, being female (AOR 1.53, 95% CI 1.03–2.27, p = 0.003) and age group of 31–40 years (AOR 2.85; 95% CI 1.56, 5.17, p = 0.001) were statistically significant factors to HBV infection. Similarly, being female (AOR 1.97, 95% CI 1.10–3.53, p = 0.02), age group of 21–30 years (AOR 2.71; 95% CI 1.15, 6.40, p = 0.02) and age group greater than 40 years (AOR 3.13; 95% CI 1.31, 7.44, p = 0.01) were significantly associated with HCV infection. In our study, high seroprevalence of HBV and HCV infection was detected among clinically suspected patients. Females and the age groups between 31 and 40 were more affected. Community awareness of the prevention and transmission of viral hepatitis infection should be strengthened through herd immunization and health education. The prospective study should be conducted in this area.

Cell-type-specific origins of locomotor rhythmicity at different speeds in larval zebrafish

Different speeds of locomotion require heterogeneous spinal populations, but a common mode of rhythm generation is presumed to exist. Here, we explore the cellular versus synaptic origins of spinal rhythmicity at different speeds by performing electrophysiological recordings from premotor excitatory interneurons in larval zebrafish. Chx10-labeled V2a neurons are divided into at least two morphological subtypes proposed to play distinct roles in timing and intensity control. Consistent with distinct rhythm generating and output patterning functions within the spinal V2a population, we find that descending subtypes are recruited exclusively at slow or fast speeds and exhibit intrinsic cellular properties suitable for rhythmogenesis at those speeds, while bifurcating subtypes are recruited more reliably at all speeds and lack appropriate rhythmogenic cellular properties. Unexpectedly, however, phasic firing patterns during locomotion in rhythmogenic and non-rhythmogenic V2a neurons alike are best explained by distinct modes of synaptic inhibition linked to cell type and speed. At fast speeds reciprocal inhibition in descending V2a neurons supports phasic firing, while recurrent inhibition in bifurcating V2a neurons helps pattern motor output. In contrast, at slow speeds recurrent inhibition in descending V2a neurons supports phasic firing, while bifurcating V2a neurons rely on reciprocal inhibition alone to pattern output. Our findings suggest cell-type-specific, not common, modes of rhythmogenesis generate and coordinate different speeds of locomotion.

Cell-type-specific origins of locomotor rhythmicity at different speeds in larval zebrafish.

Different speeds of locomotion require heterogeneous spinal populations, but a common mode of rhythm generation is presumed to exist. Here, we explore the cellular versus synaptic origins of spinal rhythmicity at different speeds by performing electrophysiological recordings from premotor excitatory interneurons in larval zebrafish. Chx10-labeled V2a neurons are divided into at least two morphological subtypes proposed to play distinct roles in timing and intensity control. Consistent with distinct rhythm generating and output patterning functions within the spinal V2a population, we find that descending subtypes are recruited exclusively at slow or fast speeds and exhibit intrinsic cellular properties suitable for rhythmogenesis at those speeds, while bifurcating subtypes are recruited more reliably at all speeds and lack appropriate rhythmogenic cellular properties. Unexpectedly, however, phasic firing patterns during locomotion in rhythmogenic and non-rhythmogenic V2a neurons alike are best explained by distinct modes of synaptic inhibition linked to cell type and speed. At fast speeds reciprocal inhibition in descending V2a neurons supports phasic firing, while recurrent inhibition in bifurcating V2a neurons helps pattern motor output. In contrast, at slow speeds recurrent inhibition in descending V2a neurons supports phasic firing, while bifurcating V2a neurons rely on reciprocal inhibition alone to pattern output. Our findings suggest cell-type-specific, not common, modes of rhythmogenesis generate and coordinate different speeds of locomotion.

MOLECULAR SURVEILLANCE OF GONOCOCCAL CIPROFLOXACIN SUSCEPTIBILITY/RESISTANCE IN BULGARIA, 2022-2023

Background: The emergence and spread of antimicrobial resistance in Neisseria gonorrhoeae is a significant public health issue, with Euro-GASP conducting surveillance across the EU-EEA. The advent of molecular diagnostics for N. gonorrhoeae may possibly limit the surveillance data because it is dependent on gonococcal culture for phenotypic susceptibility testing. Ideally, molecular diagnostics should combine identification and resistance detection but the complexity of gonococcal molecular genetics of resistance is a major barrier for test development. Currently, resistance prediction in N. gonorrhoeae is accurate only for fluoroquinolones and there are commercial kits available on the market that allow antimicrobial resistance surveillance and individualized treatment. The study examined Bulgaria's gonococcal fluoroquinolone resistance rate for 2022-2023 by molecular methods and compared it with previous years and EU-EEA trends. Methods: The commercial ResistancePlus® GC assay was used to predict ciprofloxacin susceptibility/resistance in 66 Neisseria gonorrhoeae-positive DNA samples from patients, diagnosed in 2022-2023. Results: The identified fluoroquinolone resistance rate in 2022-2023 was 68.2%. The majority of the cases were males in the age group 20-29 (50.8%), the most common mode of transmission was MSM (77%) and 17% of the cases with known HIV status were positive. Conclusion: This study found a higher than before fluoroquinolone resistance rate (68.2%) in Bulgaria, following the trend in Europe. In the EU-EEA, ciprofloxacin resistance increased to 65.9% in 2022. Molecular testing for predicting susceptibility/resistance is suitable for effective antimicrobial resistance surveillance and individualized treatment decisions.

An efficient isogeometric buckling optimization framework for multi-patch laminated shells: Leveraging 3D solid elements, lamination parameters and penalty method

Buckling is a common failure mode of laminated shell structures during service, and isogeometric analysis methods are highly suitable for the buckling analysis due to their accurate geometric modeling capability and high-order continuity. However, the isogeometric buckling analysis for a multi-patch structure and its optimal design still face challenges in computational efficiency. To address this issue, this paper proposes an integrated framework for the buckling optimization of multi-patch laminated shells, which leverages 3D solid elements, lamination parameters, and the penalty coupling method. Solid-shell elements have advantages in shell analysis due to their simplicity, absence of rotational degrees of freedom, and adaptive layering in the thickness direction. Lamination parameters simplify the optimization of fiber orientations in laminated shells by condensing the design variable space and improving the convexity of the optimization problem. The penalty method can handle the coupling in multiple patches at a relatively low cost. Nevertheless, lamination parameters are rarely applied to the case of solid-shell elements. In addition, despite using lamination parameters, the number of design variables for multi-patch structures remains significantly large. To tackle these issues, this study derives the solid-shell formulation in lamination parameters and the sensitivity analysis formulae in the reverse mode. Experiment validation is conducted to assess the accuracy of the proposed method based on lamination parameters with solid elements, the feasibility of the multi-patch optimization model, and the computational efficiency of optimization sensitivity based on the reverse mode compared to the forward counterpart common in the literature.

Scalable multiphoton generation from cavity-synchronized single-photon sources

We propose an efficient, scalable, and deterministic scheme to generate multiple indistinguishable photons over independent channels, on demand. Our design relies on multiple single-photon sources, each coupled to a waveguide, all interacting with a common cavity mode. The cavity synchronizes and triggers the simultaneous emission of one photon by each source, which are collected by the waveguides. In a state-of-the-art circuit QED implementation, this scheme supports the creation of single photons with 99% purity, indistinguishability, and efficiency at rates of ∼MHz. We also discuss conditions to produce up to 100 photons simultaneously with generation rates of hundreds of kHz. This is orders of magnitude more efficient than previous demultiplexed sources for boson sampling and enables the realization of deterministic multiphoton sources and scalable quantum information processing with photons. Published by the American Physical Society 2024