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Assessment of Outphasing Power Amplifiers and Their MMIC Implementations
Power amplifier (PA) applications consistently require increased performance for bandwidth, power, and efficiency. Modern communication and telemetry systems are required to operate across multiple bands that can span octaves while scaling down unit power amplifier cells to fit on the back-end of phased array systems. Phased array implementation scales branch complexity for both signal generation and linearization. This creates problems with conventional approaches for back-off efficiency enhancement techniques as well as increasing the importance of linearity optimization. This reduces the complexity of the digital pre-distortion (DPD) required to operate the system while maintaining high average efficiency for large peak to average power ratio (PAPR) signals.
This thesis presents advanced outphasing PA architectures. Each of the architectures answers a different design challenge for modern communication and telemetry systems. Analog signal separation reduces the need for a digital signal split removing cost, size, weight, and power (C-SWaP). Improved modeling and understanding of the design of the inphasing splitter allows for optimization of linearity and efficiency. This work looks at utilizing novel power combining implementations with reconfigurable matching networks to operate outphasing PA’s across multiple bands spanning an octave allowing for functional flexibility andreduced system complexity.
The thesis works on two distinct outphasing implementations: the RF-input outphasing power amplifier (RFIO PA) and the dual-input reconfigurable outphasing power amplifier (DIRO PA). The designs presented in this work are as follows:
• Hybrid X-band RFIO PA utilizing a previously designed dual-input X-band outphasing monolithic microwave integrated circuit (MMIC) in an unreleased Qorvo GaN 150 nm process
• Hybrid X-band RFIO PA utilizing three different non-linear elements (PIN diode, diode-connected transistor, and mesa resistor) in the signal splitter design to optimize for linearity and efficiency in conjunction with a custom designed dual-input outphasing PA MMIC in Qorvo 150 nm GaN es process
• MMIC RFIO PA utilizing diode-connected transistors for integrated signal splitter design in Qorvo 150 nm GaN es process
• MMIC 6-12 GHz reconfigurable outphasing combiner with a switchable shunt line to control reactive loading in Qorvo’s GaAs 250 nm process
• MMIC DIRO PA which is reconfigurable from 18-38 GHz with >2 GHz of instantaneous bandwidth in the WIN semiconductor PIH-110 process</p
Tunable narrowband Excitonic Optical Tamm States enabled by a metal-free all-organic structure
Optical Tamm States (OTS) are confined optical modes that can occur at the
interface between two highly reflective structures. However, due to the strong
reflectance required, their implemen-tation with highly processable and
metal-free flexible materials has proven challenging. Herein, we develop the
first structure supporting OTS based only on organic polymeric materials,
demon-strating a photonic platform based on non-critical, widely available, and
easily processable mate-rials. The structures fabricated present large areas
and consist of a narrowband multi-layered polymeric Distributed Bragg Reflector
(DBR) followed by a thin film of J-aggregate molecular exci-tonic material that
can act as a highly reflective surface within a narrowband range. We take
ad-vantage of the narrowband spectral response of the DBR and of the reflective
molecular layer to tune the OTS band by varying the periodicity of the
multilayer, opening the door for the fabrica-tion of OTS structures based on
lightweight integrable excitonic devices with cost-effective proce-dures.Comment: 15 pages, 8 (3+5) figures, supplementary information include
The decay constant of the holographic techni-dilaton and the 125 GeV boson
We critically discuss the possibility that the 125 GeV boson recently
discovered at the LHC is the holographic techni-dilaton, a composite state
emerging from a strongly-coupled model of electroweak symmetry breaking. This
composite state differs from the SM for three main reasons. Its decay constant
is in general larger than the electroweak scale, hence suppressing all the
couplings to standard model particles with respect to an elementary Higgs
boson, with the exception of the coupling to photons and gluons, which is
expected to be larger than the standard-model equivalent.
We discuss three classes of questions. Is it possible to lower the decay
constant, by changing the geometry of the holographic model? Is it possible to
lower the overall scale of the strong dynamics, by modifying the way in which
electroweak symmetry breaking is implemented in the holographic model? Is there
a clear indication in the data that production mechanisms other than
gluon-gluon fusion have been observed, disfavoring models in which the
holographic techni-dilaton has a large decay constant?
We show that all of these questions are still open, given the present status
of theoretical as well as phenomenological studies, and that at present the
techni-dilaton hypothesis yields a fit to the data which is either as good as
the elementary Higgs hypothesis, or marginally better, depending on what sets
of data are used in the fit. We identify clear strategies for future work aimed
at addressing these three classes of open questions.
In the process, we also compute the complete scalar spectrum of the
two-scalar truncation describing the GPPZ model, as well as the decay constant
of the holographic techni-dilaton in this model.Comment: 23 pages, 7 figures. Two paragraphs of general comments added.
Several references added. Version accepted for publicatio
Impact of the first COVID lockdown on accident- and injury-related pediatric intensive care admissions in Germany - a multicenter study
Childrenâs and adolescentsâ lives drastically changed during COVID lockdowns worldwide. To compare accident- and injury-related admissions to pediatric intensive care units (PICU) during the first German COVID lockdown with previous years, we conducted a retrospective multicenter study among 37 PICUs (21.5% of German PICU capacities). A total of 1444 admissions after accidents or injuries during the first lockdown period and matched periods of 2017â2019 were reported and standardized morbidity ratios (SMR) were calculated. Total PICU admissions due to accidents/injuries declined from an average of 366 to 346 (SMR 0.95 (CI 0.85â1.05)). Admissions with trauma increased from 196 to 212 (1.07 (0.93â1.23). Traffic accidents and school/kindergarten accidents decreased (0.77 (0.57â1.02 and 0.26 (0.05â0.75)), whereas household and leisure accidents increased (1.33 (1.06â1.66) and 1.34 (1.06â1.67)). Less neurosurgeries and more visceral surgeries were performed (0.69 (0.38â1.16) and 2.09 (1.19â3.39)). Non-accidental non-suicidal injuries declined (0.73 (0.42â1.17)). Suicide attempts increased in adolescent boys (1.38 (0.51â3.02)), but decreased in adolescent girls (0.56 (0.32â0.79)). In summary, changed trauma mechanisms entailed different surgeries compared to previous years. We found no evidence for an increase in child abuse cases requiring intensive care. The increase in suicide attempts among boys demands investigation
Abatacept, Cenicriviroc, or Infliximab for Treatment of Adults Hospitalized With COVID-19 Pneumonia: A Randomized Clinical Trial
IMPORTANCE: Immune dysregulation contributes to poorer outcomes in COVID-19.
OBJECTIVE: To investigate whether abatacept, cenicriviroc, or infliximab provides benefit when added to standard care for COVID-19 pneumonia.
DESIGN, SETTING, AND PARTICIPANTS: Randomized, double-masked, placebo-controlled clinical trial using a master protocol to investigate immunomodulators added to standard care for treatment of participants hospitalized with COVID-19 pneumonia. The results of 3 substudies are reported from 95 hospitals at 85 clinical research sites in the US and Latin America. Hospitalized patients 18 years or older with confirmed SARS-CoV-2 infection within 14 days and evidence of pulmonary involvement underwent randomization between October 2020 and December 2021.
INTERVENTIONS: Single infusion of abatacept (10 mg/kg; maximum dose, 1000 mg) or infliximab (5 mg/kg) or a 28-day oral course of cenicriviroc (300-mg loading dose followed by 150 mg twice per day).
MAIN OUTCOMES AND MEASURES: The primary outcome was time to recovery by day 28 evaluated using an 8-point ordinal scale (higher scores indicate better health). Recovery was defined as the first day the participant scored at least 6 on the ordinal scale.
RESULTS: Of the 1971 participants randomized across the 3 substudies, the mean (SD) age was 54.8 (14.6) years and 1218 (61.8%) were men. The primary end point of time to recovery from COVID-19 pneumonia was not significantly different for abatacept (recovery rate ratio [RRR], 1.12 [95% CI, 0.98-1.28]; Pâ=â.09), cenicriviroc (RRR, 1.01 [95% CI, 0.86-1.18]; Pâ=â.94), or infliximab (RRR, 1.12 [95% CI, 0.99-1.28]; Pâ=â.08) compared with placebo. All-cause 28-day mortality was 11.0% for abatacept vs 15.1% for placebo (odds ratio [OR], 0.62 [95% CI, 0.41-0.94]), 13.8% for cenicriviroc vs 11.9% for placebo (OR, 1.18 [95% CI 0.72-1.94]), and 10.1% for infliximab vs 14.5% for placebo (OR, 0.59 [95% CI, 0.39-0.90]). Safety outcomes were comparable between active treatment and placebo, including secondary infections, in all 3 substudies.
CONCLUSIONS AND RELEVANCE: Time to recovery from COVID-19 pneumonia among hospitalized participants was not significantly different for abatacept, cenicriviroc, or infliximab vs placebo.
TRIAL REGISTRATION: ClinicalTrials.gov Identifier: NCT04593940
Gene co-expression architecture in peripheral blood in a cohort of remitted first-episode schizophrenia patients
A better understanding of schizophrenia subtypes is necessary to stratify the patients according to clinical attributes. To explore the genomic architecture of schizophrenia symptomatology, we analyzed blood co-expression modules and their association with clinical data from patients in remission after a first episode of schizophrenia. In total, 91 participants of the 2EPS project were included. Gene expression was assessed using the Clariom S Human Array. Weighted-gene co-expression network analysis (WGCNA) was applied to identify modules of co-expressed genes and to test its correlation with global functioning, clinical symptomatology, and premorbid adjustment. Among the 25 modules identified, six modules were significantly correlated with clinical data. These modules could be clustered in two groups according to their correlation with clinical data. Hub genes in each group showing overlap with risk genes for schizophrenia were enriched in biological processes related to metabolic processes, regulation of gene expression, cellular localization and protein transport, immune processes, and neurotrophin pathways. Our results indicate that modules with significant associations with clinical data showed overlap with gene sets previously identified in differential gene-expression analysis in brain, indicating that peripheral tissues could reveal pathogenic mechanisms. Hub genes involved in these modules revealed multiple signaling pathways previously related to schizophrenia, which may represent the complex interplay in the pathological mechanisms behind the disease. These genes could represent potential targets for the development of peripheral biomarkers underlying illness traits in clinical remission stages after a first episode of schizophrenia
Gut Microbiome Dysbiosis in Antibiotic-Treated COVID-19 Patients is Associated with Microbial Translocation and Bacteremia
Although microbial populations in the gut microbiome are associated with COVID-19 severity, a causal impact on patient health has not been established. Here we provide evidence that gut microbiome dysbiosis is associated with translocation of bacteria into the blood during COVID-19, causing life-threatening secondary infections. We first demonstrate SARS-CoV-2 infection induces gut microbiome dysbiosis in mice, which correlated with alterations to Paneth cells and goblet cells, and markers of barrier permeability. Samples collected from 96 COVID-19 patients at two different clinical sites also revealed substantial gut microbiome dysbiosis, including blooms of opportunistic pathogenic bacterial genera known to include antimicrobial-resistant species. Analysis of blood culture results testing for secondary microbial bloodstream infections with paired microbiome data indicates that bacteria may translocate from the gut into the systemic circulation of COVID-19 patients. These results are consistent with a direct role for gut microbiome dysbiosis in enabling dangerous secondary infections during COVID-19
Drosophila evolution over space and time (DEST):A new population genomics resource
Drosophila melanogaster is a leading model in population genetics and genomics, and a growing number of whole-genome datasets from natural populations of this species have been published over the last years. A major challenge is the integration of disparate datasets, often generated using different sequencing technologies and bioinformatic pipelines, which hampers our ability to address questions about the evolution of this species. Here we address these issues by developing a bioinformatics pipeline that maps pooled sequencing (Pool-Seq) reads from D. melanogaster to a hologenome consisting of fly and symbiont genomes and estimates allele frequencies using either a heuristic (PoolSNP) or a probabilistic variant caller (SNAPE-pooled). We use this pipeline to generate the largest data repository of genomic data available for D. melanogaster to date, encompassing 271 previously published and unpublished population samples from over 100 locations inâ>â20 countries on four continents. Several of these locations have been sampled at different seasons across multiple years. This dataset, which we call Drosophila Evolution over Space and Time (DEST), is coupled with sampling and environmental meta-data. A web-based genome browser and web portal provide easy access to the SNP dataset. We further provide guidelines on how to use Pool-Seq data for model-based demographic inference. Our aim is to provide this scalable platform as a community resource which can be easily extended via future efforts for an even more extensive cosmopolitan dataset. Our resource will enable population geneticists to analyze spatio-temporal genetic patterns and evolutionary dynamics of D. melanogaster populations in unprecedented detail.DrosEU is funded by a Special Topic Networks (STN) grant from the European Society for Evolutionary Biology (ESEB). MK (M. Kapun) was supported by the Austrian Science Foundation (grant no. FWF P32275); JG by the European Research Council (ERC) under the European Unionâs Horizon 2020 research and innovation programme (H2020-ERC-2014-CoG-647900) and by the Spanish Ministry of Science and Innovation (BFU-2011-24397); TF by the Swiss National Science Foundation (SNSF grants PP00P3_133641, PP00P3_165836, and 31003A_182262) and a Mercator Fellowship from the German Research Foundation (DFG), held as a EvoPAD Visiting Professor at the Institute for Evolution and Biodiversity, University of MĂŒnster; AOB by the National Institutes of Health (R35 GM119686); MK (M. Kankare) by Academy of Finland grant 322980; VL by Danish Natural Science Research Council (FNU) grant 4002-00113B; FS Deutsche Forschungsgemeinschaft (DFG) grant STA1154/4-1, Project 408908608; JP by the Deutsche Forschungsgemeinschaft Projects 274388701 and 347368302; AU by FPI fellowship (BES-2012-052999); ET Israel Science Foundation (ISF) grant 1737/17; MSV, MSR and MJ by a grant from the Ministry of Education, Science and Technological Development of the Republic of Serbia (451-03-68/2020-14/200178); AP, KE and MT by a grant from the Ministry of Education, Science and Technological Development of the Republic of Serbia (451-03-68/2020-14/200007); and TM NSERC grant RGPIN-2018-05551.Peer reviewe
ECMO for COVID-19 patients in Europe and Israel
Since March 15th, 2020, 177 centres from Europe and Israel have joined the study, routinely reporting on the ECMO support they provide to COVID-19 patients. The mean annual number of cases treated with ECMO in the participating centres before the pandemic (2019) was 55. The number of COVID-19 patients has increased rapidly each week reaching 1531 treated patients as of September 14th. The greatest number of cases has been reported from France (n = 385), UK (n = 193), Germany (n = 176), Spain (n = 166), and Italy (n = 136) .The mean age of treated patients was 52.6 years (range 16â80), 79% were male. The ECMO configuration used was VV in 91% of cases, VA in 5% and other in 4%. The mean PaO2 before ECMO implantation was 65 mmHg. The mean duration of ECMO support thus far has been 18 days and the mean ICU length of stay of these patients was 33 days. As of the 14th September, overall 841 patients have been weaned from ECMO
support, 601 died during ECMO support, 71 died after withdrawal of ECMO, 79 are still receiving ECMO support and for 10 patients status n.a. . Our preliminary data suggest that patients placed
on ECMO with severe refractory respiratory or cardiac failure secondary to COVID-19 have a reasonable (55%) chance of survival. Further extensive data analysis is expected to provide invaluable information on the demographics, severity of illness, indications and different ECMO management strategies in these patients
Study of the decay
The decay is studied
in proton-proton collisions at a center-of-mass energy of TeV
using data corresponding to an integrated luminosity of 5
collected by the LHCb experiment. In the system, the
state observed at the BaBar and Belle experiments is
resolved into two narrower states, and ,
whose masses and widths are measured to be where the first uncertainties are statistical and the second
systematic. The results are consistent with a previous LHCb measurement using a
prompt sample. Evidence of a new
state is found with a local significance of , whose mass and width
are measured to be and , respectively. In addition, evidence of a new decay mode
is found with a significance of
. The relative branching fraction of with respect to the
decay is measured to be , where the first
uncertainty is statistical, the second systematic and the third originates from
the branching fractions of charm hadron decays.Comment: All figures and tables, along with any supplementary material and
additional information, are available at
https://cern.ch/lhcbproject/Publications/p/LHCb-PAPER-2022-028.html (LHCb
public pages
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