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Abstract We show that nearly-degenerate Vertical External-Cavity Surface-Emitting Lasers may emit a set of tilted beams of individually addressable mode-locked pulses. These time localized beams feature a Gaussian profile and they are emitted in pairs with opposite transverse k-vector. Because they are phase locked, their interference leads to a non homothetic pattern in the near-field emission of the laser. In the simplest situation, when a single pair is emitted, this is a stripe pattern. Our analysis discloses the role of third order (spherical) aberrations of the cavity in stabilizing this spatio-temporal mode-locked regime and in selecting the value of the transverse k-vector.

Large-scale food fortification (LSFF) programs are widely implemented in low- and middle-income countries (LMIC) to alleviate micronutrient deficiencies. However, these programs may not achieve the desired impact due to poor design or bottlenecks in program implementation. Monitoring and evaluation (M&E) frameworks and a set of agreed indicators can help to benchmark progress and to strengthen the evidence-base of effectiveness in a standardized way. We aimed to formulate recommendations towards core indicators for evaluating the effectiveness of LSFF programs with their associated metrics, methods, and tools (IMMT). For this, we used a multi-method iterative approach, including a mapping review of the literature, semi-structured interviews with international experts, compilation of a generic Theory of Change (ToC) framework for LSFF program delivery, and selection of IMMT for M&E of LSFF programs at key stages along the ToC delivery framework. Lastly, we conducted exploratory, qualitative interviews with key informants in Nigeria to explore experiences and perceptions related to the implementation of LSFF programs in Nigeria’s context, and their opinion towards the proposed set of core IMMT. The literature search resulted in 14 published and 15 grey literature documents, from which we extracted a total of 41 indicators. Based on the available literature and interviews with international experts, we mapped a ToC delivery framework and selected nine core indicators at the output, outcome and impact level for M&E of the effectiveness of LSFF programs. Key informants in Nigeria revealed that the main bottlenecks for implementation of the proposed IMMT are related to the lack of technical capacity, equipment, laboratory infrastructure, and financial resources. In conclusion, we propose a set of nine core indicators for enabling comprehensive M&E of the effectiveness of LSFF programs in LMIC. This proposed set of core indicators can be used for further evaluation, harmonization and integration in national and international protocols for M&E of LSFF programs.

Sound monitoring and evaluation (M&E) systems are needed to inform effective biofortification program management and implementation. Despite the existence of M&E frameworks for biofortification programs, the use of indicators, metrics, methods, and tools (IMMT) are currently not harmonized, rendering the tracking of biofortification programs difficult. We aimed to compile IMMT for M&E of existing biofortification programs and recommend a sub-set of high-level indicators (HLI) for a harmonized global M&E framework. We conducted (1) a mapping review to compile IMMT for M&E biofortification programs; (2) semi-structured interviews (SSIs) with biofortification programming experts (and other relevant stakeholders) to contextualize findings from step 1; and (3) compiled a generic biofortification program Theory of Change (ToC) to use it as an analytical framework for selecting the HLI. This study revealed diversity in seed systems and crop value chains across countries and crops, resulting in differences in M&E frameworks. Yet, sufficient commonalities between implementation pathways emerged. A set of 17 HLI for tracking critical results along the biofortification implementation pathway represented in the ToC is recommended for a harmonized global M&E framework. Further research is needed to test, revise, and develop mechanisms to harmonize the M&E framework across programs, institutions, and countries.

We demonstrate the existence of coexisting frequency combs in a harmonically mode-locked laser that we link to the splay phases of the Kuramoto model with short range interactions. These splay states are multistable and the laser may wander between them under the influence of stochastic forces. Consequently, the many pulses circulating in the cavity are not necessarily coherent with each other. As these partially disordered states for the phase of the field still feature regular intensity pulses, we term them as incoherent crystals of optical pulses. We provide evidence that the notion of coherence should be interpreted by comparing the duration of the measurement time with the Kramers' escape time of each splay state. Our theoretical results are confirmed experimentally by performing high resolution spectral measurements via a heterodyne technique of a passively mode-locked vertical external-cavity surface-emitting laser.

Purpose: Neurogenic orthostatic hypotension (nOH) is a frequent nonmotor feature of Parkinson's disease (PD), associated with adverse outcomes. Recently, 24-h ambulatory blood pressure monitoring (ABPM) showed good accuracy in diagnosing nOH. This study aims at evaluating the prognostic role of ABPM-hypotensive episodes in predicting PD disability milestones and mortality and comparing it to the well-defined prognostic role of bedside nOH., Methods: Patients with PD who underwent ABPM from January 2012 to December 2014 were retrospectively enrolled and assessed for the development of falls, fractures, dementia, bed/wheelchair confinement, hospitalization, and mortality, during an up-to-10-year follow-up. Significant ABPM-hypotensive episodes were identified when greater than or equal to two episodes of systolic BP drop ≥ 15 mmHg (compared with the average 24 h) were recorded during the awakening-to-lunch period., Results: A total of 99 patients (74% male, age 64.0 ± 10.1 years, and PD duration 6.4 ± 4.0 years) were enrolled. At baseline, 38.4% of patients had ABPM-hypotensive episodes and 46.5% had bedside nOH. On Kaplan-Meier analysis, patients with ABPM-hypotensive episodes showed earlier onset of falls (p = 0.001), fractures (p = 0.004), hospitalizations (p = 0.009), bed/wheelchair confinement (p = 0.032), dementia (p = 0.001), and shorter survival (8.0 versus 9.5 years; p = 0.009). At Cox regression analysis (adjusted for age, disease duration, Charlson Comorbidity Index, and Hoehn and Yahr stage) a significant association was confirmed between ABPM-hypotensive episodes and falls [odds ratio (OR) 3.626; p = 0.001), hospitalizations (OR 2.016; p = 0.038), and dementia (OR 2.926; p = 0.008), while bedside nOH was only associated with falls (OR 2.022; p = 0.039) and dementia (OR 1.908; p = 0.048)., Conclusions: The presence of at least two ABPM-hypotensive episodes independently predicted the development of falls, dementia, and hospitalization, showing a stronger prognostic value than the simple bedside assessment., (© 2024. Springer-Verlag GmbH Germany.)

Aim: Contrast-enhanced cardiac magnetic resonance (Ce-CMR) and Fluorine-18 fluorodeoxyglucose positron emission tomography (FDG-PET) are frequently utilized in clinical practice to assess myocardial viability. However, studies evaluating direct comparison between Ce-CMR and FDG-PET have a smaller sample size, and no clear distinction between the two imaging modalities has been defined. To address this gap, we conducted a meta-analysis of studies comparing Ce-CMR and FDG-PET for the assessment of myocardial viability., Methods: We searched PubMed, EMBASE, Scopus, and Web of Science databases from their inception to 4/20/2022 with search terms "viability" AND "heart diseases" AND "cardiac magnetic resonance imaging" AND "positron-emission tomography." We extracted patient characteristics, segment level viability assessment according to Ce-CMR and FDG-PET, and change in regional wall motion abnormalities (RWMA) at follow-up., Results: We included four studies in the meta-analysis which provided viability assessment with Ce-CMR and FDG-PET in all patients and change in RWMA at follow-up. There were 82 patients among the four included studies, and 585 segments were compared for viability assessment. There were 59 (72%) males, and mean age was 65 years. The sensitivity (95% confidence interval-CI) and specificity (CI) of Ce-CMR for predicting myocardial recovery were 0.88 (0.66-0.96) and 0.64 (0.49-0.77), respectively. The sensitivity (CI) and specificity (CI) of FDG-PET for predicting myocardial recovery were 0.91 (0.63-0.99) and 0.67 (0.49-0.81), respectively., Conclusion: FDG-PET and Ce-CMR have comparable diagnostic parameters in myocardial viability assessment and are consistent with prior research., (© 2023. The Author(s) under exclusive licence to American Society of Nuclear Cardiology.)

We investigate the turn-on process in a laser cavity where the round-trip time is several orders of magnitude greater than the active medium timescales. In this long delay limit, we show that the universal evolution of the photon statistics from thermal to Poissonian distribution involves the emergence of power dropouts. While the largest number of these dropouts vanish after a few round-trips, some of them persist and seed coherent structures similar to dark solitons or Nozaki-Bekki holes described by the complex Ginzburg-Landau equation. These coherent structures connect stationary laser emission domains having different optical frequencies. Moreover, they emit intensity bursts which travel at a different speed, and, depending on the cavity dispersion sign, they may collide with other coherent structures, thus leading to an overall turbulent dynamics. The dynamics is well-modeled by delay differential equations from which we compute the laser coherence time evolution at each round-trip and quantify the decoherence induced by the collisions between coherent structures.

Deploying advanced imaging solutions to robotic and autonomous systems by mimicking human vision requires simultaneous acquisition of multiple fields of views, named the peripheral and fovea regions. Among 3D computer vision techniques, LiDAR is currently considered at the industrial level for robotic vision. Notwithstanding the efforts on LiDAR integration and optimization, commercially available devices have slow frame rate and low resolution, notably limited by the performance of mechanical or solid-state deflection systems. Metasurfaces are versatile optical components that can distribute the optical power in desired regions of space. Here, we report on an advanced LiDAR technology that leverages from ultrafast low FoV deflectors cascaded with large area metasurfaces to achieve large FoV (150°) and high framerate (kHz) which can provide simultaneous peripheral and central imaging zones. The use of our disruptive LiDAR technology with advanced learning algorithms offers perspectives to improve perception and decision-making process of ADAS and robotic systems., (© 2022. The Author(s).)

Cardiac sarcoidosis (CS) frequently leads to ventricular tachycardia (VT), which is often refractory to antiarrhythmic and/or immunosuppressive medications and requires catheter ablation. We conducted a systematic review and meta-analysis to evaluate the role of catheter ablation in patients with refractory VT undergoing catheter ablation. We searched PubMed, Embase, and Scopus databases from their inception to December 31, 2021 with search terms "cardiac sarcoidosis" AND "electrophysiological studies OR ablation." Fifteen studies were ultimately included for evaluation. Patient demographics, VT mapping, and acute and long-term procedural outcomes were extracted. A total of 15 studies were included in our meta-analysis, with a total of 401 patients, of whom 66% were male, with ages ranging from 39 to 64 years. A total of 95% of patients were on antiarrhythmics and 79% of patients were on immunosuppressants. Left ventricular ejection fraction ranged from 35% to 49% and procedure duration ranged from 269 to 462 minutes. Ablation was reported using both irrigated and nonirrigated catheter tips. A total of 25% of patients (84/339) underwent repeat ablation. Acute procedural success was achieved in 57% (161/285). Procedure complications occurred in 5.7% (17/297) procedures. VT recurrence after first ablation was 55% (confidence interval 48% to 63%, 213/401); VT recurrence after multiple ablations was 37% (81/220). The composite end point of death, heart transplant, and left ventricular assist device implantation was 21% (confidence interval 14% to 30%, 55/297). In conclusion, catheter ablation is a useful modality in patients with CS with refractory VT. However, patients with CS presenting with refractory VT after undergoing VT ablation carry a poor prognosis., Competing Interests: Disclosures The authors have NO conflict of interests to declare., (Copyright © 2022 Elsevier Inc. All rights reserved.)

Defibrillation threshold (DFT) testing is performed in individuals with higher predicted risks of defibrillation failure. Many strategies have been explored to overcome the challenge of high DFT, including an insertion of a defibrillator lead into the azygos vein. We performed a systematic review of the literature to evaluate the safety and efficacy of azygos vein implantable cardioverter-defibrillator insertion for high DFT combined with the analysis of a single-center experience of the procedure at our institution. The literature search was performed in PubMed and Embase from database inception to December 2020 to identify all case reports and case series related to azygos vein defibrillator lead insertion. Our search identified 291 records. After excluding duplicate studies and those without DFT thresholds and non-azygos vascular destinations, 12 studies (23 cases) were reviewed from the current database. We also conducted a retrospective analysis of 5 cases performed at our institution, and a total of 28 patients were included in our final analysis. The mean age of the pooled cohort was 47 years (range, 17-88 years). Men composed 92% of the total cases, and the average body mass index was 34 kg/m 2 . The mean ejection fraction (EF) was 25%, with 78% having non-ischemic cardiomyopathy. The left axillary (36%) or subclavian (48%) vein was the common percutaneous access point. The mean duration of azygos vein access and lead delivery was 22 min (range, 13-60 min). The average DFT prior to azygos coil insertion was 35 J (range, 20-45 J). Fifty-seven percent of cases achieved substantial DFT improvement, whereas 18% achieved relative improvement compared to the pre-procedural threshold. No immediate or remote procedure-related complications were reported in 24 cases where data were available. During an average follow-up period of 18 months, 5 patients had ventricular arrhythmic events requiring device therapy and 4 had successful cardioversion from the device. One patient died from cardiac arrest with variable device therapies of both unsuccessful and successful events. In conclusion, azygos vein defibrillator lead insertion has a considerable rate of success, ease of vascular access with minimal procedural time, and lower risks and complications. Larger studies and longer follow-up periods are warranted to establish its efficacy and safety., Competing Interests: The authors report no conflicts of interest for the published content., (Copyright: © 2022 Innovations in Cardiac Rhythm Management.)

In spite of cardiovascular system (CVS) response to posture changes have been widely studied, a number of mechanisms and their interplay in regulating central blood pressure and organs perfusion upon orthostatic stress are not yet clear. We propose a novel multiscale 1D-0D mathematical model of the human CVS to investigate the effects of passive (i.e., through head-up tilt without muscular intervention) posture changes. The model includes the main short-term regulation mechanisms and is carefully validated against literature data and in vivo measures here carried out. The model is used to study the transient and steady-state response of the CVS to tilting, the effects of the tilting rate, and the differences between tilt-up and tilt-down. Passive upright tilt led to an increase of mean arterial pressure and heart rate, and a decrease of stroke volume and cardiac output, in agreement with literature data and present in vivo experiments. Pressure and flow rate waveform analysis along the arterial tree together with mechano-energetic and oxygen consumption parameters highlighted that the whole system approaches a less stressed condition at passive upright posture than supine, with a slight unbalance of the energy supply-demand ratio. The transient dynamics is not symmetric in tilt-up and tilt-down testing, and is non-linearly affected by the tilting rate, with stronger under- and overshoots of the hemodynamic parameters as the duration of tilt is reduced. By enriching the CVS response to posture changes, the present modeling approach shows promise in a number of applications, ranging from autonomic system disorders to spaceflight deconditioning., Competing Interests: The authors declare that the research was conducted in the absence of any commercial or financial relationships that could be construed as a potential conflict of interest., (Copyright © 2022 Fois, Maule, Giudici, Valente, Ridolfi and Scarsoglio.)

Background: The utility of an electrophysiologic study (EPS) in the risk stratification of cardiac sarcoidosis (CS) patients is not clear. We conducted a systemic review and meta-analysis to evaluate the utility of EPS in the risk stratification of CS patients., Methods: We searched PubMed, Embase, and Scopus databases from their inception to 12/4/2020 with search terms "Cardiac sarcoidosis" And "Electrophysiological studies OR ablation". The first and second authors reviewed all the studies. We extracted the data of positive and negative EPS, and outcomes defined as ventricular arrhythmias, implantable cardioverter defibrillator therapy, death, left ventricular assist device placement, or heart transplantation. Risk of bias assessment was done by the Quality Assessment of Diagnostic Accuracy Studies-2 tool. Subgroup analysis of patients with left ventricular ejection fraction (LVEF) >35%, and probable CS, no prior ventricular tachycardia (VT) and LVEF >35% were performed., Results: We found 544 articles after removing duplicates. A total of 52 full articles were reviewed, and eight studies were included in the meta-analysis. The pooled sensitivity and specificity (95% confidence interval) of EPS in predicting clinical outcomes were 0.70 (0.51-0.85) and 0.93 (0.85-0.97), respectively. Subgroup analysis of patients with LVEF >35% resulted in pooled sensitivity of 0.63 (0.29-0.88) and pooled specificity of 0.97 (0.92-0.99), and subgroup analysis of patients with probable CS, no prior VT, and LVEF >35% resulted in pooled sensitivity of 0.71 (0.33-0.93) and pooled specificity of 0.96 (0.88-0.99) in predicting adverse clinical outcomes., Conclusions: EPS is an effective risk stratification tool in patients with CS across all subgroups with high sensitivity and specificity., (Copyright © 2021 Elsevier B.V. All rights reserved.)