Edge Couplers with relaxed Alignment Tolerance for Pick-and-Place Hybrid Integration of III-V Lasers with SOI Waveguides

We report on two edge-coupling and power splitting devices for hybrid integration of III-V lasers with sub-micrometric silicon-on-insulator (SOI) waveguides. The proposed devices relax the horizontal alignment tolerances required to achieve high coupling efficiencies and are suitable for passively aligned assembly with pick-and-place tools. Light is coupled to two on-chip single mode SOI waveguides with almost identical power coupling efficiency, but with a varying relative phase accommodating the lateral misalignment between the laser diode and the coupling devices, and is suitable for the implementation of parallel optics transmitters. Experimental characterization with both a lensed fiber and a Fabry-P\'erot semiconductor laser diode has been performed. Excess insertion losses (in addition to the 3 dB splitting) taken as the worst case over both waveguides of respectively 2 dB and 3.1 dB, as well as excellent 1 dB horizontal loss misalignment ranges of respectively 2.8 um and 3.8 um (worst case over both in-plane axes) have been measured for the two devices. Back-reflections to the laser are below -20 dB for both devices within the 1 dB misalignment range. Devices were fabricated with 193 nm DUV optical lithography and are compatible with mass-manufacturing with mainstream CMOS technology

Damping of relaxation oscillations,photon-photon resonance, and tolerance to external optical feedback of III-V/SiN hybrid lasers with dispersive narrow band mirror

We address the stability of a tunable hybrid laser based on a III-V Reflective Semiconductor Optical Amplifier (RSOA) edge-coupled with a Silicon Photonic (SiPh) dispersive mirror through a model of time-delayed algebraic differential equations that accounts for the narrow band mirror. Our results allow to (i) analyze the stability of single mode lasing, (ii) quantify the impact of the mirror bandwidth on the damping of the laser relaxation oscillations and the emergence of photon-photon resonance, and (iii) study the tolerance of the laser to the external optical feedback. Thanks to this analysis, we find a mirror design that gives ultra-high stability up to an external feedback level of −10 dB. The aim of the work is providing a tool for understanding and interpreting the dynamics of these lasers and design configurations for isolator-free operation

Efficient and Optical Feedback Tolerant Hybrid Laser Design for Silicon Photonics Applications

We present a design of a tunable hybrid laser based on III-V Reflective Semiconductor Optical Amplifier (RSOA) and Silicon Photonics (SiPh) external mirror that represents a good trade off between high Wall-Plug Efficiency (WPE) and high tolerance to optical feedback caused by unwanted back reflections from the rest of the SiPh chip. The sensitivity to optical feedback of different configurations, an important issue in many SiPh applications, is evaluated through the calculation of the critical feedback level based on an effective Lang-Kobayashi model and the main results are validated through numerical simulations of laser dynamics. We conclude that hybrid lasers with long effective external cavities typically designed to reduce the laser linewidth can be also exploited to improve the tolerance to spurious optical feedback

Is the Parkland grading scale related to surgical difficulty in laparoscopic cholecystectomy?

Background: Acute cholecystitis is one of the most frequent surgical pathologies, accounting for 6-11% of patients with symptomatic gallstone disease. The gold-standard treatment for this disease is laparoscopic cholecystectomy because the minimally invasive surgery significantly benefits the patient in terms of less pain and early recovery. The Parkland grading scale (PGS) is a grading system based solely on intraoperative images, which stratifies gallbladder inflammation in five degrees based on anatomy and gallbladder inflammation. This grading system is useful and helps predict the outcome of the surgery.Methods: This study correlated the PGS with surgical difficulty based on factors such as open conversion and subtotal cholecystectomy. We included 105 patients in this study who, over a seven-month period, underwent a laparoscopic cholecystectomy and were graded by the PGS.Results: We enrolled a total of 105 patients in our study, in which 74 patients were female and 31 were male. Of the 105 patients, 94 had a laparoscopic cholecystectomy, 3 underwent an open conversion (meaning the conversion rate was 2.9%), and 8 had a subtotal cholecystectomy (a rate of 7.6%).Conclusions: The PGS is an easy and applicable grading scale for surgeons, and its application could help predict the complexity of gallbladder surgery and the outcomes of each patient. However, additional high-quality studies are needed to asses and validate this scale in patients with acute cholecystitis and determine its predictive value. We should also adjust this study depending on the surgeons’ level of expertise.

Assessment of a New Lateral Cushioned Casting Orthosis: Effects on Peroneus Longus Muscle Electromyographic Activity During Running

Background: Classical medial wedge (CMW) orthoses have been prescribed to treat overpronation foot pathologies in runners. The effects of a novel supination orthosis (NSO) on the surface electromyography (EMG) activity of the peroneus longus (PL) muscle during a complete cycle of running have yet to be tested. Purpose/Hypothesis: The purpose of this study was to compare the EMG activity of the PL in participants wearing CMW orthoses and NSOs versus neutral running shoes (NRS) during a full cycle of running gait. It was hypothesized that the PL muscle activity would be lower for the NSO compared with CMW or NRS. Study Design: Controlled laboratory study. Methods: Included were 31 healthy recreational runners of both sexes (14 male and 17 female; mean age, 38.58 ± 4.02 years) with a neutral Foot Posture Index and standard rearfoot-strike pattern. Participants ran on a treadmill at 9 km/h while wearing NSO (3-, 6-, and 9-mm thicknesses), CMW (3-, 6-, and 9-mm thicknesses), and NRS, for a total of 7 different conditions randomly selected, while the EMG signal activity of the PL was recorded for 30 seconds. Each trial was recorded 3 times, and the intraclass correlation coefficient (ICC) to test reliability of the measurements was calculated. The Wilcoxon pair to pair nonparametric test with Bonferroni correction was performed to analyze differences among the conditions. Results: The reliability of all assessments was almost perfect (ICC, >0.81). For both the CMW and NSO, regardless of thickness, the PL activity was statistically significantly lower compared with the NRS (P < .05 for all). For all CMW thicknesses, the PL activity was lower compared with the respective NSO thicknesses, with the 3-mm thickness having the largest difference (CMW3mm, 18.63 ± 4.64 vs NSO3mm, 20.78 ± 4.99 mV; P < .001). Conclusion: Both CMW and NSO produced reduced EMG activity of the PL muscle; therefore, they can be prescribed to treat overpronation pathologies without associated PL strain concerns. In addition, the NSO saved the enhancement material placed on the medial-rear side of CMW, making it easier to wear sports shoes. Clinical Relevance: Knowing the safety of CMW and NSO will aid in understanding treatments for overpronation pathologies

MERLIN: a novel BRET-based proximity biosensor for studying mitochondria–ER contact sites

The contacts between the ER and mitochondria play a key role in cellular functions such as the exchange of lipids and calcium between both organelles, as well as in apoptosis and autophagy signaling. The molecular architecture and spatiotemporal regulation of these distinct contact regions remain obscure and there is a need for new tools that enable tackling these questions. Here, we present a new bioluminescence resonance energy transfer-based biosensor for the quantitative analysis of distances between the ER and mitochondria that we call MERLIN (Mitochondria-ER Length Indicator Nanosensor). The main advantages of MERLIN compared with available alternatives are that it does not rely on the formation of artificial physical links between the two organelles, which could lead to artifacts, and that it allows to study contact site reversibility and dynamics. We show the applicability of MERLIN by characterizing the role of the mitochondrial dynamics machinery on the contacts of this organelle with the ER.We thank Peter McCormick for helpful advice and discussion and Carolin Stegmuller, Sabine Schafer, Iris Koch, Maria Zarani, Astrid Schauss, Christian Jungst, Felix Babatz, and Marina Nikolova for technical support. This work has been partially supported by the Deutsche Forschungsgemeinschaft (FOR2036 GA1641/2-1 and GA1641/2-2) and the European Research Council (StG 309966)

Natural co‐infection of divergent hepatitis B and C virus homologues in carnivores

In humans, co-infection of hepatitis B and C viruses (HBV, HCV) is common and aggravates disease outcome. Infection-mediated disease aggravation is poorly understood, partly due to lack of suitable animal models. Carnivores are understudied for hepatitis virus homologues. We investigated Mexican carnivores (ringtails, Bassariscus astutus) for HBV and HCV homologues. Three out of eight animals were infected with a divergent HBV termed ringtail HBV (RtHBV) at high viral loads of 5 x 10(9) -1.4 x 10(10) copies/ml serum. Two of the RtHBV-infected animals were co-infected with a divergent hepacivirus termed ringtail hepacivirus (RtHV) at 4 x 10(6)-7.5 x 10(7) copies/ml in strain-specific qRT-PCR assays. Immunofluorescence assays relying on HBV core and RtHV NS3/4a proteins indicated that none of the animals had detectable hepadnavirus core-specific antibodies, whereas one RtHV-infected animal had concomitant RtHV-specific antibodies at 1:800 end-point titre. RtHBV and RtHV complete genomes showed typical HBV and HCV structure and length. All RtHBV genomes were identical, whereas RtHV genomes showed four amino acid substitutions located predominantly in the E1/E2-encoding genomic regions. Both RtHBV (>28% genomic nucleotide sequence distance) and RtHV (>30% partial NS3/NS5B amino acid sequence distance) formed new species within their virus families. Evolutionary analyses showed that RtHBV grouped with HBV homologues from different laurasiatherian hosts (carnivores, bats, and ungulates), whereas RtHV grouped predominantly with rodent-borne viruses. Ancestral state reconstructions showed that RtHV, but not RtHBV, likely emerged via a non-recent host switch involving rodent-borne hepacivirus ancestors. Conserved hepatitis virus infection patterns in naturally infected ringtails indicate that carnivores may be promising animal models to understand HBV/HCV co-infection

Pasado y futuro de la infección por VIH. Un documento basado en la opinión de expertos

[EN] HIV infection is now almost 40 years old. In this time, along with the catastrophe and tragedy that it has entailed, it has also represented the capacity of modern society to take on a challenge of this magnitude and to transform an almost uniformly lethal disease into a chronic illness, compatible with a practically normal personal and relationship life. This anniversary seemed an ideal moment to pause and reflect on the future of HIV infection, the challenges that remain to be addressed and the prospects for the immediate future. This reflection has to go beyond merely technical approaches, by specialized professionals, to also address social and ethical aspects. For this reason, the Health Sciences Foundation convened a group of experts in different aspects of this disease to discuss a series of questions that seemed pertinent to all those present. Each question was presented by one of the participants and discussed by the group. The document we offer is the result of this reflection. [ES] La infección por VIH cumple ahora casi 40 años de existencia. En este tiempo, junto a la catástrofe y la tragedia que ha supuesto, ha representado también la capacidad de la sociedad moderna de asumir un reto de esta magnitud y de transformar, gracias al tratamiento antirretroviral, una enfermedad mayoritariamente letal en una enfermedad crónica, compatible con una vida personal y de relación prácticamente normales. Este aniversario parecía un momento idóneo para pararse a reflexionar sobre el futuro de la infección VIH, los retos que todavía quedan por abordar y las perspectivas para el inmediato futuro. Esa reflexión tiene que ir más allá de planteamientos meramente técnicos, de profesionales especializados, para abordar aspectos sociales y éticos. Por este motivo, la Fundación de Ciencias de la Salud convocó a un grupo de expertos en distintos aspectos de esta infección para discutir una serie de preguntas que parecieron pertinentes a todos los convocados. Cada pregunta era expuesta por uno de los participantes y discutida por el grupo. El documento que ofrecemos es el resultado de esa reflexión.For transparency purposes, we would like to inform you that GSK has contributed to the funding of this publication. Its content reflects the authors’ own opinions, criteria, conclusions and/or findings, which may not necessarily coincide with those of GSK. GSK always recommends that its products are used in accordance with the technical data sheet approved by the health authorities.S

Constraints on Higgs boson production with large transverse momentum using H →b b ¯ decays in the ATLAS detector

This paper reports constraints on Higgs boson production with transverse momentum above 1 TeV. The analyzed data from proton-proton collisions at a center-of-mass energy of 13 TeV were recorded with the ATLAS detector at the Large Hadron Collider from 2015 to 2018 and correspond to an integrated luminosity of 136 fb-1. Higgs bosons decaying into bb¯ are reconstructed as single large-radius jets recoiling against a hadronic system and are identified by the experimental signature of two b-hadron decays. The experimental techniques are validated in the same kinematic regime using the Z→bb¯ process. The 95% confidence-level upper limit on the cross section for Higgs boson production with transverse momentum above 450 GeV is 115 fb, and above 1 TeV it is 9.6 fb. The Standard Model cross section predictions for a Higgs boson with a mass of 125 GeV in the same kinematic regions are 18.4 fb and 0.13 fb, respectively