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The pandemic diffusion of the SARS-CoV-2 infection throughout the world required measures to prevent and strategies to control the infection, as well as the reallocation of the hospital structures in order to take care of an increased number of infected patients. Endoscopy Units should be able to perform endoscopic procedures on COVID-19 infected as well as on noninfected patients. The aim of this manuscript is to propose a model for a fast reorganization of the endoscopy department environment in order to safely perform endoscopic procedures in this Pandemic COVID-19 scenario, according to the current advices given by the Scientific Societies.

We tackle the problem of a network switch enforcing fair bandwidth sharing of the same link among many TCP-like senders. Most of the mechanisms to solve this problem are based on complex scheduling algorithms, whose feasibility becomes very expensive with today's line rate requirements, i.e. 10–100 Gbit/s per port. We propose a new scheme called FDPA in which we do not modify the scheduler, but instead we use an array of rate estimators to dynamically assign traffic flows to an existing strict priority scheduler serving only few queues. FDPA is inspired by recent advances in programmable stateful data planes. We propose a design that uses primitives common in data plane abstractions such as P4 and OpenFlow. We conducted experiments on a physical 10 Gbit/s testbed, we present preliminary results showing that FDPA produces fairness comparable to approaches based on scheduling.

Supporting the programming of stateful packet forwarding functions in hardware has recently attracted the interest of the research community. When designing such switching chips, the challenge is to guarantee the ability to program functions that can read and modify data plane's state, while keeping line rate performance and state consistency. Current state-of-the-art designs are based on a very conservative all-or-nothing model: programmability is limited only to those functions that are guaranteed to sustain line rate, with any traffic workload. In effect, this limits the maximum time to execute state update operations. In this paper, we explore possible options to relax these constraints by using simulations on real traffic traces. We then propose a model in which functions can be executed in a larger but bounded time, while preventing data hazards with memory locking. We present results showing that such flexibility can be supported with little or no throughput degradation., Comment: 6 pages

Background. Automatic systems for stabilizing blood pressure (BP) during dialysis are few and only control those variables indirectly related to BP. Due to complex BP regulation under dynamic dialysis conditions, BP itself appears to be the most consistent input parameter for a device addressed to preventing dialysis hypotension (DH). Methods. An automatic system (ABPS, automatic blood pressure stabilization) for BP control by fluid removal feedback regulation is implemented on a dialysis machine (Dialog Advanced, Braun). A fuzzy logic (FL) control runs in the system, using instantaneous BP as the input variable governing the ultrafiltration rate (UFR) according to the BP trend. The system is user-friendly and just requires the input of two data: critical BP (individually defined as the possible level of DH risk) and the highest UFR applicable (percentage of the mean UFR). We evaluated this system’s capacity to prevent DH in 55 RDT hypotension-prone patients. Sessions with (treatment A) and without (treatment B) ABPS were alternated one-by-one for 30 dialysis sessions per patient (674 with ABPS vs 698 without). Results. Despite comparable treatment times and UF volumes, severe DH appeared in 8.3% of sessions in treatment A vs 13.8% in treatment B (� 39%, P ¼ 0.01). Mild DH fell non-significantly (� 12.3%). There was a similar percentage of sessions in which the planned body weight loss was not achieved and dialysis time was prolonged. Conclusions. In conclusion, FL may be suited to interpreting and controlling the trend of a determined multi-variable parameter like BP. The medical knowledge of the patient and the consequent updating of input parameters depending on the patient’s clinical conditions seem to be the main factors for obtaining optimal results.

When dealing with node or link failures in Software Defined Networking (SDN), the network capability to establish an alternative path depends on controller reachability and on the round trip times (RTTs) between controller and involved switches. Moreover, current SDN data plane abstractions for failure detection (e.g. OpenFlow "Fast-failover") do not allow programmers to tweak switches' detection mechanism, thus leaving SDN operators still relying on proprietary management interfaces (when available) to achieve guaranteed detection and recovery delays. We propose SPIDER, an OpenFlow-like pipeline design that provides i) a detection mechanism based on switches' periodic link probing and ii) fast reroute of traffic flows even in case of distant failures, regardless of controller availability. SPIDER can be implemented using stateful data plane abstractions such as OpenState or Open vSwitch, and it offers guaranteed short (i.e. ms) failure detection and recovery delays, with a configurable trade off between overhead and failover responsiveness. We present here the SPIDER pipeline design, behavioral model, and analysis on flow tables' memory impact. We also implemented and experimentally validated SPIDER using OpenState (an OpenFlow 1.3 extension for stateful packet processing), showing numerical results on its performance in terms of recovery latency and packet losses., 8 pages

The successful OpenFlow approach to Software Defined Networking (SDN) allows network programmability through a central controller able to orchestrate a set of dumb switches. However, the simple match/action abstraction of OpenFlow switches constrains the evolution of the forwarding rules to be fully managed by the controller. This can be particularly limiting for a number of applications that are affected by the delay of the slow control path, like traffic management applications. Some recent proposals are pushing toward an evolution of the OpenFlow abstraction to enable the evolution of forwarding policies directly in the data plane based on state machines and local events. In this paper, we present two traffic management applications that exploit a stateful data plane and their prototype implementation based on OpenState, an OpenFlow evolution that we recently proposed., 6 pages, 9 figures

This paper presents a hardware implementation of Openstate, an extension of OpenFlow that allows performing stateful control functionalities directly inside the switch, without requiring the intervention of an external controller. The paper shows how, with a minimal reworking of the OpenFlow's basic architecture, and reusing the same building blocks, it is possible to greatly extend the intelligence of an OpenFlow switch allowing the offload of many control task directly in the switch. An FPGA based implementation of an Openstate prototype is here presented, the different architectural design choices are discussed, and the performance and limitations of the developed prototype are examinated. Finally, the paper proposes a discussion on the performance achievable by using an ASIC implementation of the OpenState switch1.

Dent’s disease (DD) involves nephrocalcinosis, urolithiasis, hypercalciuria, LMW proteinuria, and renal failure in various combinations. Males are affected. It is caused by mutations in the chloride channel CLCN5 gene. It has been suggested that DD is underdiagnosed, occurring in less overt forms, apparently without family history. A possible approach to this problem is to search for CLCN5 mutations in patients who may have a high prevalence of mutations: end-stage renal disease (ESRD) patients with previous calcium, struvite, or radio-opaque (CSR) stones. We looked for CLCN5 mutations in 25 males with ESRD–CSR stones selected from all of the patients (1,901 individuals, of which 1,179 were males) of 15 dialysis units in the Veneto region. One DD patient had a new DD mutation (1070 G>T) in exon 7. The new polymorphism IVS11–67 C>T was detected in intron 11 in one patient and one control. We also found 28 females with ESRD and stone history, and seven more males with ESRD and non-CSR stones. The prevalence of stone formers among dialysis patients in our region was 3.2%, much lower than the prevalence observed in older studies. Struvite stones continue to play a major role in causing stone-associated ESRD .

Equivalence of information from single versus multiple frequency bioimpedance vector analysis in hemodialysis. Background In suspended cells, low-frequency current only passes through extracellular fluids, while current at higher frequencies passes through extra- and intracellular fluids. Cells in soft tissues are in contact with each other, which causes tissue anisotropy, meaning that impedance changes along different cell directions, with part of low-frequency current also passing through cells. Hence, equivalent information on body impedance change is expected at all frequencies, which we proved in a dynamic condition of fluid removal with hemodialysis. Methods We performed whole-body impedance spectroscopy (496 frequencies from 4 to 1024kHz, SEAC SFB3 analyzer; Brisbane, Australia) before and during fluid removal (0, 60, 120, 180min, 2.5kg) in 67 hemodialysis patients. With increasing current frequency, resistance (R) decreases and reactance (Xc) moves along the Cole's semicircle on the R-Xc plane. Results The Cole's semicircles progressively enlarged and moved to the right on the R-Xc plane following fluid removal (increase in both R and Xc values at any given frequency). Xc values at 5kHz (expected values close to 0 Ohm) were 70% of the maximun Xc, indicating an intracellular current flows at low frequencies. The correlation coefficient between R at 50kHz (standard frequency) and R at other frequencies ranged from 0.96 to 0.99, and the correlation coefficient between Xc at 50kHz and Xc at other frequencies at any time point ranged from 0.65 to 0.99. Conclusion From high Xc values at low frequency, tissue anisotropy is inferred. Intra- and extracellular current flow causes equivalence of information based on functions of R and Xc measurements made at 50kHz versus other frequencies.

A reliable and scalable mechanism to provide protection against a link or node failure has additional requirements in the context of SDN and OpenFlow. Not only it has to minimize the load on the controller, but it must be able to react even when the controller is unreachable. In this paper we present a protection scheme based on precomputed backup paths and inspired by MPLS crankback routing, that guarantees instantaneous recovery times and aims at zero packet-loss after failure detection, regardless of controller reachability, even when OpenFlow's "fast-failover" feature cannot be used. The proposed mechanism is based on OpenState, an OpenFlow extension that allows a programmer to specify how forwarding rules should autonomously adapt in a stateful fashion, reducing the need to rely on remote controllers. We present the scheme as well as two different formulations for the computation of backup paths., 8 pages, pre-print, Design of Reliable Communication Networks (DRCN), 2015 11th International Conference on the

SUMMARY When dealing with node or link failures in software-defined networking (SDN), the network capability to establish an alternative path depends on controller reachability and on the round-trip times between controller and involved switches. Moreover, current SDN data plane abstractions for failure detection, such as OpenFlow “Fast-failover,” do not allow programmers to tweak switches' detection mechanism, thus leaving SDN operators relying on proprietary management interfaces (when available) to achieve guaranteed detection and recovery delays. We propose SPIDER, an OpenFlow-like pipeline design that provides (i) a detection mechanism based on switches' periodic link probing and (ii) fast reroute of traffic flows even in the case of distant failures, regardless of controller availability. SPIDER is based on stateful data plane abstractions such as OpenState or P4, and it offers guaranteed short (few milliseconds or less) failure detection and recovery delays, with a configurable trade-off between overhead and failover responsiveness. We present here the SPIDER pipeline design, behavioral model, and analysis on flow tables' memory impact. We also implemented and experimentally validated SPIDER using OpenState (an OpenFlow 1.3 extension for stateful packet processing) and P4, showing numerical results on its performance in terms of recovery latency and packet loss.

Introduction: Vitamin D receptor activator (VDRA) therapy has been shown to be associated with reduced mortality rates in chronic kidney disease (CKD) patients with secondary hyperparathyroidism (SHPT). However, differences between VDRAs in their ability to reduce both all-cause and cardiovascular-related mortality rates are not yet fully elucidated. Methods: The objective of the current analysis was to determine the effect of VDRA therapy on mortality in an Italian dialysis population, observed prospectively every 6 months for 18 months. Patients were investigated for all-cause and cardiovascular-related mortality risk adjusted for various demographic, clinical, and/or SHPT treatment variables. Results: The cumulative probabilities of all-cause and cardiovascular-related mortality were lower for patients who received any VDRA treatment compared with those who did not (p < 0.001) regardless of all measured variables. Additionally, patients who received paricalcitol and/or cinacalcet (with or without VDRAs) compared with calcitriol showed a significant improvement in both all-cause and cardiovascular-related mortality (p < 0.001). Cinacalcet with or without VDRAs was not associated with a further decrease of mortality hazard ratios compared with paricalcitol monotherapy. Conclusions: VDRA therapy (associated or not with cinacalcet) was associated with improved survival in dialysis patients, independent of demographic and clinical variables.

Background. Increased oxidative stress (OxSt) as well as inflammation are risk factors for cardiovascular events and determinant of cardiovascular disease which remains the most common cause of excess morbidity and mortality for end-stage renal disease ESRD patients. Haemodiafiltration with on-line regeneration of ultrafiltrate (HFR) has been shown to have a positive impact on markers of inflammation while its effect on OxSt is not known. Methods. This study evaluates in haemodialysis patients the effect of HFR on the plasma level of oxidized LDL (OxLDL), a marker of OxSt, and mononuclear cell gene and protein expression of OxSt-related proteins such as p22 phox (subunit of NAD(P)H oxidase), PAI-1 (induced by OxSt and atherothrombogenetic) and haeme-oxygenase-1 (HO-1) (induced by OxSt). Fourteen patients were randomized into two groups in a crossover design, treated for 6 month periods with HFR (SG8 Plus-Bellco, Mirandola, Italy) or low-flux bicarbonate dialysis (HD) using a polysulphone dialyser 1.8 m 2 . Blood samples were collected at the beginning of the study, after 6 months (crossover) and after 12 months. Results. ANOVA analysis of the data performed to rule out any crossover effect in either sequence was not significant and thus data from both sequences were combined and then analysed further statistically. HFR reduced mRNA production and protein expression of p22 phox and PAI-1 compared with HD (� 9 � 5 vs 2 � 6 %, P < 0.0001 and � 15 � 20 vs 3 � 17 %, P < 0.05 for p22 phox ; � 19 � 6 vs � 5 � 5 %, P < 0.0001 and � 24 � 12 vs 9 � 15 %, P < 0.0001 for PAI-1). HO-1 was unchanged (� 12 � 8 vs � 10 � 8 % and � 21 � 12 vs � 14 � 8 %) while plasma OxLDL was reduced (� 14 � 19 vs 1 � 14 %, P < 0.01). Conclusions. The results of our study indicate that HFR treatment, compared with standard dialysis, has a lower impact on OxSt. Given, the strong relationship between OxSt and inflammation and their impact on the long-term cardiovascular complications in endstage renal disease patients, HFR might have a more beneficial impact in reducing the risk of atherosclerotic cardiovascular disease in dialysis patients.

Calcium channel blockers (CCBs) are effective blood pressure lowering agents, giving rise to a prevalent dilation of the afferent arteriole. Manidipine, a long-lasting dihydropyridine CCB, demonstrates its action not only on the afferent arteriole, but also on the efferent one. This suggests theoretically a renoprotective effect in patients with chronic kidney diseases (CKD).This was a multicenter, prospective, randomized, double-blind, parallel group study, to evaluate the efficacy and tolerability of manidipine (M; 10-20 mg/day), in comparison with enalapril (E; 10-20 mg/day) in the treatment of hypertension in 136 patients with CKD secondary to primary renoparenchymal disease. Changes in blood pressure values from baseline were considered as the primary outcome of the study. Proteinuria changes and the rate of renal function decline were also evaluated.During a 48-week follow-up, mean SBP decreased from 155+/-11.7 to 138.7+/-13.9 mmHg in M and from 157.3 +/-11.8 to 134.2+/-13.9 mmHg in E; mean DBP decreased from 100.3+/-4.2 to 86.1+/-6.5 mmHg in M and from 100.3+/-4.2 to 84.7+/-6.3 mmHg in E. Proteinuria remained unchanged in M (from 1.6+/-1.59 to 1.62+/-1.79 g/24h), and decreased significantly in E (from 1.37+/-1.45 g/24h to 1+/-1.55 g/24h). No significant difference was observed in the rate of renal function decline in the two groups.Manidipine was safe and effective, obtaining a significant reduction in SBP and DBP from baseline. Although patients treated with enalapril showed a better antiproteinuric response, the two treatments were equally effective in reducing the rate of CRF progression in patients without glomerular disease.