The QUIC Fix for Optimal Video Streaming

Within a few years of its introduction, QUIC has gained traction: a significant chunk of traffic is now delivered over QUIC. The networking community is actively engaged in debating the fairness, performance, and applicability of QUIC for various use cases, but these debates are centered around a narrow, common theme: how does the new reliable transport built on top of UDP fare in different scenarios? Support for unreliable delivery in QUIC remains largely unexplored. The option for delivering content unreliably, as in a best-effort model, deserves the QUIC designers' and community's attention. We propose extending QUIC to support unreliable streams and present a simple approach for implementation. We discuss a simple use case of video streaming---an application that dominates the overall Internet traffic---that can leverage the unreliable streams and potentially bring immense benefits to network operators and content providers. To this end, we present a prototype implementation that, by using both the reliable and unreliable streams in QUIC, outperforms both TCP and QUIC in our evaluations.Comment: Published to ACM CoNEXT Workshop on the Evolution, Performance, and Interoperability of QUIC (EPIQ

Dry side of the core: a meta-analysis addressing the original nature of the ABA signalosome at the onset of seed imbibition

The timing of seedling emergence is a major agricultural and ecological fitness trait, and seed germination is controlled by a complex molecular network including phytohormone signalling. One such phytohormone, abscisic acid (ABA), controls a large array of stress and developmental processes, and researchers have long known it plays a crucial role in repressing germination. Although the main molecular components of the ABA signalling pathway have now been identified, the molecular mechanisms through which ABA elicits specific responses in distinct organs is still enigmatic. To address the fundamental characteristics of ABA signalling during germination, we performed a meta-analysis focusing on the Arabidopsis dry seed proteome as a reflexion basis. We combined cutting-edge proteome studies, comparative functional analyses, and protein interaction information with genetic and physiological data to redefine the singular composition and operation of the ABA core signalosome from the onset of seed imbibition. In addition, we performed a literature survey to integrate peripheral regulators present in seeds that directly regulate core component function. Although this may only be the tip of the iceberg, this extended model of ABA signalling in seeds already depicts a highly flexible system able to integrate a multitude of information to fine-tune the progression of germination

Efficient production of soluble recombinant single chain Fv fragments by a Pseudomonas putida strain KT2440 cell factory

<p>Abstract</p> <p>Background</p> <p>Recombinant antibody fragments have a wide range of applications in research, diagnostics and therapy. For many of these, small fragments like single chain fragment variables (scFv) function well and can be produced inexpensively in bacterial expression systems. Although <it>Escherichia coli </it>K-12 production systems are convenient, yields of different fragments, even those produced from codon-optimized expression systems, vary significantly. Where yields are inadequate, alternative production systems are needed. <it>Pseudomonas putida </it>strain KT2440 is a versatile biosafety strain known for good expression of heterologous genes, so we have explored its utility as a cell factory for production of scFvs.</p> <p>Results</p> <p>We have generated new broad host range scFv expression constructs and assessed their production in the <it>Pseudomonas putida </it>KT2440 host. Two scFvs bind either to human C-reactive protein or to mucin1, proteins of significant medical diagnostic and therapeutic interest, whereas a third is a model anti-lysozyme scFv. The KT2440 antibody expression systems produce scFvs targeted to the periplasmic space that were processed precisely and were easily recovered and purified by single-step or tandem affinity chromatography. The influence of promoter system, codon optimization for <it>P. putida</it>, and medium on scFv yield was examined. Yields of up to 3.5 mg/l of pure, soluble, active scFv fragments were obtained from shake flask cultures of constructs based on the original codon usage and expressed from the <it>Ptac </it>expression system, yields that were 2.5-4 times higher than those from equivalent cultures of an <it>E. coli </it>K-12 expression host.</p> <p>Conclusions</p> <p><it>Pseudomonas putida </it>KT2440 is a good cell factory for the production of scFvs, and the broad host range constructs we have produced allow yield assessment in a number of different expression hosts when yields in one initially selected are insufficient. High cell density cultivation and further optimization and refinement of the KT2440 cell factory will achieve additional increases in the yields of scFvs.</p

Early Work: Path Selection in a Path-aware Network Architecture

Modern path-aware networking (PAN) architectures based on packet-carried forwarding state (PCFS) promise to support practical multipath communication with increased availability and redundancy, even for single-homed hosts. How exactly hosts can chose paths in a meaningful way while maintaining good network utilization as well as user satisfaction is the subject of this research. We demonstrate how overall network utilization is affected by the introduction of multipath communication and propose the term “Cost of Multipath” to reason about this observation. We also identify a collection of concrete practical techniques from networking research and engineering that can be adapted to allow hosts to make more informed path decisions. These tie into the practical implementation of an experimental path-selection engine with a high-level API that we aim to utilize to quantitatively investigate host-based approaches for traffic optimization in the existing path-aware SCION network architectur

ABI5 binding protein2 inhibits ABA responses during germination without ABA-INSENSITIVE5 degradation.

Overexpression of ABA-INSENSITIVE5 binding proteins (AFPs) results in extreme ABA resistance of seeds and failure to acquire desiccation tolerance, at least in part through effects on chromatin modification. We tested the hypothesis that AFPs promote germination in Arabidopsis (Arabidopsis thaliana) by also functioning as adapters for E3 ligases that ubiquitinate ABI5, leading to its degradation. Interactions between AFPs and two well-characterized classes of E3 ligases targeting ABI5, DWD HYPERSENSITIVE TO ABA (DWA)s and KEEP ON GOING, were analyzed by yeast two-hybrid, bimolecular fluorescence complementation, and genetic assays. Although weak direct interactions were detected between AFPs and E3 ligases, loss of function for these E3 ligases did not impair ABA-resistance conferred by overexpression of the YFP-AFP2 fusion. Comparison of ABI5 and AFP2 levels in these lines showed that AFP2 accumulation increased during germination, but that ABI5 degradation followed germination, demonstrating that AFP2 overexpression reduces ABA sensitivity, thereby permitting germination prior to ABI5 degradation. Surprisingly, AFP2 overexpression in the dwa1 dwa2 mutant background produced the unusual combination of extreme ABA resistance and desiccation tolerance, creating an opportunity to separate the underlying biochemical characteristics of ABA sensitivity and desiccation tolerance. Our quantitative proteomics analysis identified at least three-fold more differentially accumulated seed proteins than previous studies. Comparison of dry seed proteomes of wild-type or dwa1 dwa2 mutants with or without AFP2 overexpression allowed us to separate and refine the changes in protein accumulation patterns associated with desiccation tolerance independently of ABA sensitivity, or vice versa, to a subset of cold-induced and defense stress-responsive proteins and signaling regulators

Current status and evolution of robotic-assisted thoracic surgery in Germany—results from a nationwide survey

Background: Robot-assisted surgery has made a significant entry into surgical practice within Germany, including thoracic surgery. As no published data exists regarding robotic-assisted thoracic surgery (RATS), we conducted a survey to investigate its current status. Methods: We performed a nationwide survey of all centers active in RATS, using a standardized questionnaire. The annual number of operations, mean duration of surgery, docking time, length of hospital stay(s), conversions, chest tube duration, the RATS program start date, robot system used, operating room capacity, and staplers and instruments used were recorded. Results: Of the 22 centers contacted, 14 responded. In total, 786 RATS interventions were recorded. Most were anatomical lung resections, comprising 372 (bi-) lobectomies and 80 segmentectomies. During the study period, eight bronchoplastic procedures were performed robotically. There were 93 wedge lung resections, 148 thymectomies, 26 sympathectomies, and 59 other RATS procedures, and a single-center series of around 1,000 RATS thymectomies (excluded from statistical analysis). The average incision-suture time of the RATS lobectomy was 245 (range, 80-419) minutes, average residence time seven days. The conversion rate was 6.7% across all interventions, with significant inter-intervention differences. All surveyed centers plan to further expand RATS, with OR capacity being a frequent impediment. Five RATS interventions were performed in Germany in 2013, versus 320 in 2018. Conclusions: Overall, RATS is becoming more established in everyday clinical practice in Germany. The number of operations, active centers, and trained RATS surgeons has increased steadily since 2013. A German-speaking operation course for entry into RATS already exists. Even extended resections can be carried out safely, and RATS has become standard procedure in some centers

Immunomodulating Effect of the Consumption of Watercress (Nasturtium officinale) on Exercise-Induced Inflammation in Humans

The vegetable watercress (Nasturtium officinale R.Br.) is, besides being a generally nutritious food, a rich source of glucosinolates. Gluconasturtiin, the predominant glucosinolate in watercress, has been shown to have several health beneficial properties through its bioactive breakdown product phenethyl isothiocyanate. Little is known about the immunoregulatory effects of watercress. Moreover, anti-inflammatory effects have mostly been shown in in vitro or in animal models. Hence, we conducted a proof-of-concept study to investigate the effects of watercress on the human immune system. In a cross-over intervention study, 19 healthy subjects (26.5 ± 4.3 years; 14 males, 5 females) were given a single dose (85 g) of fresh self-grown watercress or a control meal. Two hours later, a 30 min high-intensity workout was conducted to promote exercise-induced inflammation. Blood samples were drawn before, 5 min after, and 3 h after the exercise unit. Inflammatory blood markers (IL-1β, IL-6, IL-10, TNF-α, MCP-1, MMP-9) were analyzed in whole blood cultures after ex vivo immune cell stimulation via lipopolysaccharides. A mild pro-inflammatory reaction was observed after watercress consumption indicated by an increase in IL-1β, IL-6, and TNF-α, whereas the immune response was more pronounced for both pro-inflammatory and anti-inflammatory markers (IL-1β, IL-6, IL-10, TNF-α) after the exercise unit compared to the control meal. During the recovery phase, watercress consumption led to a stronger anti-inflammatory downregulation of the pro-inflammatory cytokines IL-6 and TNF-α. In conclusion, we propose that watercress causes a stronger pro-inflammatory response and anti-inflammatory counter-regulation during and after exercise. The clinical relevance of these changes should be verified in future studies

EUDAQ—a data acquisition software framework for common beam telescopes

EUDAQ is a generic data acquisition software developed for use in conjunction with common beam telescopes at charged particle beam lines. Providing high-precision reference tracks for performance studies of new sensors, beam telescopes are essential for the research and development towards future detectors for high-energy physics. As beam time is a highly limited resource, EUDAQ has been designed with reliability and ease-of-use in mind. It enables flexible integration of different independent devices under test via their specific data acquisition systems into a top-level framework. EUDAQ controls all components globally, handles the data flow centrally and synchronises and records the data streams. Over the past decade, EUDAQ has been deployed as part of a wide range of successful test beam campaigns and detector development applications

Neutron irradiation and electrical characterisation of the first 8” silicon pad sensor prototypes for the CMS calorimeter endcap upgrade

International audienceAs part of its HL-LHC upgrade program, the CMS collaboration is replacing its existing endcap calorimeters with a high-granularity calorimeter (CE). The new calorimeter is a sampling calorimeter with unprecedented transverse and longitudinal readout for both electromagnetic and hadronic compartments. Due to its compactness, intrinsic time resolution, and radiation hardness, silicon has been chosen as active material for the regions exposed to higher radiation levels. The silicon sensors are fabricated as 20 cm (8”) wide hexagonal wafers and are segmented into several hundred pads which are read out individually. As part of the sensor qualification strategy, 8” sensor irradiation with neutrons has been conducted at the Rhode Island Nuclear Science Center (RINSC) and followed by their electrical characterisation in 2020-21. The completion of this important milestone in the CE's R&D program is documented in this paper and it provides detailed account of the associated infrastructure and procedures.The results on the electrical properties of the irradiated CE silicon sensors are presented