The clinical utility of lung clearance index in early cystic fibrosis lung disease is not impacted by the number of multiple-breath washout trials

© ERS 2018. The lung clearance index (LCI) from the multiple-breath washout (MBW) test is a promising surveillance tool for pre-school children with cystic fibrosis (CF). Current guidelines for MBW testing recommend that three acceptable trials are required. However, success rates to achieve these criteria are low in children aged < 7 years and feasibility may improve with modified pre-school criteria that accepts tests with two acceptable trials. This study aimed to determine if relationships between LCI and clinical outcomes of CF lung disease differ when only two acceptable MBW trials are assessed. Healthy children and children with CF aged 3–6 years were recruited for MBW testing. Children with CF also underwent bronchoalveolar lavage fluid collection and a chest computed tomography scan. MBW feasibility increased from 46% to 75% when tests with two trials were deemed acceptable compared with tests where three acceptable trials were required. Relationships between MBW outcomes and markers of pulmonary inflammation, infection and structural lung disease were not different between tests with three acceptable trials compared with tests with two acceptable trials. This study indicates that pre-school MBW data from two acceptable trials may provide sufficient information on ventilation distribution if three acceptable trials are not possible

Rose Bengal sensitized bilayered photoanode of nano-crystalline TiO–CeO for dye-sensitized solar cell application

There are two traditional ways to read Kant’s claim that every event necessarily has a cause: the weaker every-event some-cause (WCP) and the stronger same-cause same-effect (SCP) causal principles. The debate on whether and where he subscribes to the SCP has focused on the Analogies in the Critique of Pure Reason (Guyer, Allison, and Watkins) and on the Metaphysical Foundations of Natural Science (Friedman). By analysing the arguments and conclusions of both the Analogies and the Postulates, as well as the two Latin principles non datur casus and non datur fatum that summarise their results, I will argue that the SCP is actually demonstrated in the Postulates section of the First Critique

Mucus accumulation in the lungs precedes structural changes and infection in children with cystic fibrosis

Although destructive airway disease is evident in young children with cystic fibrosis (CF), little is known about the nature of the early CF lung environment triggering the disease. To elucidate early CF pulmonary pathophysiology, we performed mucus, inflammation, metabolomic, and microbiome analyses on bronchoalveolar lavage fluid (BALF) from 46 preschool children with CF enrolled in the Australian Respiratory Early Surveillance Team for Cystic Fibrosis (AREST CF) program and 16 non-CF disease controls. Total airway mucins were elevated in CF compared to non-CF BALF irrespective of infection, and higher densities of mucus flakes containing mucin 5B and mucin 5AC were observed in samples from CF patients. Total mucins and mucus flakes correlated with inflammation, hypoxia, and oxidative stress. Many CF BALFs appeared sterile by culture and molecular analyses, whereas other samples exhibiting bacterial taxa associated with the oral cavity. Children without computed tomography–defined structural lung disease exhibited elevated BALF mucus flakes and neutrophils, but little/no bacterial infection. Although CF mucus flakes appeared “permanent” because they did not dissolve in dilute BALF matrix, they could be solubi-lized by a previously unidentified reducing agent (P2062), but not N-acetylcysteine or deoxyribonuclease. These findings indicate that early CF lung disease is characterized by an increased mucus burden and inflammatory markers without infection or structural lung disease and suggest that mucolytic and anti-inflammatory agents should be explored as preventive therapy

Enabling low-latency applications using programmable networks

Throughout the last decades, communication networks have become embedded into almost every aspect of our day-to-day lives (e.g., watching movies, online shopping, sharing moments with friends and family). Moreover, as the support for the transport of audio and video became the norm, new application domains have kept emerging every day. One of these, the Tactile Internet, enables the transport of the sense of touch. Consequently, it allows the end-users to interact with a remote environment in the same way they would if they were present locally. While such applications could revolutionize many industries by enabling users to transport their skills (e.g., surgical skills) across the globe, they pose many new challenges to communication networks, such as the need for very low latency. Yet, providing low latency is fundamentally different from providing high bandwidth, and, as this thesis demonstrates, existing solutions developed for bandwidth-oriented services are not directly applicable to low-latency services. This thesis explores how programmable networks can be used to facilitate emerging low-latency services. Specifically, it combines the advantages of (1) Software-Defined-Networking (SDN), a paradigm in networking that centralizes the control plane, and (2) programmable data planes, which enable an on-the-fly deployment of novel algorithms to the network switches. In particular, this thesis explores what SDN controller tasks are feasible to be offloaded to the data plane, the trade-offs in doing so, and their benefits on low-latency applications. Moreover, it takes advantage of the more fine-grained monitoring possibilities of programmable data planes and incorporates these measurements into the data plane algorithms. As a result, this thesis develops a set of solutions that enable network switches to react to short-term changes in the networking traffic and act independently (or with limited input), improving the Quality of Service (QoS) of low-latency flows.First, we investigate the limitations of programmable switches and ways to overcome them by developing an application to detect heavy hitters (e.g., flows that consume most resources in the network). Next, we explore the concept of network slicing, i.e., reserving part of a physical network for a specific service. We demonstrate that network switches can combine data plane measurements and limited (preconfigured) input from the central controller to enable elasticity, i.e., the ability to automatically scale the assigned network resources based on the flows' requirements with negligible delay. Next, we analyze the co-existence and interactions between flows using different congestion control algorithms and/or having different RTTs. We use this information to develop a data plane algorithm to improve their interactions. Finally, we demonstrate how congestion detection and avoidance can be achieved in the data plane without any assistance from the end-hosts.Embedded and Networked System

P4air: Increasing Fairness among Competing Congestion Control Algorithms

Congestion control algorithms are usually developed in isolation without thoroughly investigating their co-existence and interactions with other protocols and/or congestion control algorithms. As a result, flows using different algorithms and/or having different Round-Trip Times may overpower each other, resulting in unfair resource distribution, with a subset of the flows usually claiming most of the capacity. To solve the aforementioned problem, we make use of pro- grammable switches and the network programming language P4 to enforce fairness from within the network itself, instead of from the congestion control algorithms ran at the end-points. Our solution P4air continuously monitors the properties of all flows that pass through a switch and groups them based on the behavior of the congestion control algorithms used. Furthermore, for each group, it applies appropriate measures to suppress the aggressive flows and boost smaller flows. Our experiments, using modern programmable hardware (Barefoot Tofino switch), demonstrate significant performance gains for P4air in terms of fairness compared to state-of-the-art solutions.Embedded and Networked System

Ethnobotanical knowledge of the Istro-Romanians of Zejane in Croatiǎ

Abstract An ethno-pharmacognostic survey was carried out in one of the smallest ethnic and linguistic groups in Europe: the Istro-Romanians of the village of Zejane (in Croatia), whicȟ has a population of approximately 140 persons, mainly elderly. Using an intensive field participant observation methodology, we recorded about 60 remedies of the local folk pharmacopoeia, and mainly derived from plants. Among them, the uncommon traditions to use homemade vinegar from wild apple (Malus sylvestris) and Cornelian cherries (Cornus mas) for diverse medical purposes, and houseleek (Sempervivum tectorum) against ear pains have been briefly discussed.

Fast network congestion detection and avoidance using P4

Along with exciting visions for 5G communications and the Tactile Internet, the networking requirement of attaining extremely low end-to-end latency has appeared. While network devices are typically equipped with buffers to counteract packet loss caused by short-lived traffic bursts, the more those buffers get filled, the more delay is added to every packet passing through.In this paper, we develop congestion avoidance methods that harness the power of fully programmable data-planes. The corresponding programmable switches, through languages such as P4, can be programmed to gather and react to important packet meta-data, such as queue load, while the data packets are being processed. In particular, we enable P4 switches to (1) track processing and queuing delays of latency-critical flows and (2) react immediately in the data-plane to congestion by rerouting the affected flows. Through a proof-of-concept implementation in emulation and on real hardware, we demonstrate that a data-plane approach reduces average and maximum delay, as well as jitter, when compared to non-programmable approaches

Elastic Slicing in Programmable Networks

The concept of network slicing enables operators to provision multiple virtual networks on top of a single (shared) physical infrastructure. Adding elasticity to slicing, i.e., the ability to on-demand provision/release dedicated network resources, improves resource utilization. However, efficiently allocating and scaling slice resources, while maintaining state consistency, is challenging. Especially with P4-programmab1e network devices that process packets at Tbps speeds, controller-driven scaling of network functions would be too time-consuming, and data-plane scaling is needed. In this paper, we address this need, by developing a custom scaling protocol and framework that can consistently, with negligible delay, scale network slices and functions transparently to the slice end-users. We compare, via emulation and experiments on programmable hardware, our approach to state-of-the-art scaling techniques and demonstrate significant slice resource utilization improvements and scaling duration reductions.Embedded and Networked System

Fast network congestion detection and avoidance using P4

Along with exciting visions for 5G communications and the Tactile Internet, the networking requirement of attaining extremely low end-to-end latency has appeared. While network devices are typically equipped with buffers to counteract packet loss caused by short-lived traffic bursts, the more those buffers get filled, the more delay is added to every packet passing through.In this paper, we develop congestion avoidance methods that harness the power of fully programmable data-planes. The corresponding programmable switches, through languages such as P4, can be programmed to gather and react to important packet meta-data, such as queue load, while the data packets are being processed. In particular, we enable P4 switches to (1) track processing and queuing delays of latency-critical flows and (2) react immediately in the data-plane to congestion by rerouting the affected flows. Through a proof-of-concept implementation in emulation and on real hardware, we demonstrate that a data-plane approach reduces average and maximum delay, as well as jitter, when compared to non-programmable approaches.Embedded and Networked System