Performance of Bluetooth Slave/Slave Bridge

The performance of a Bluetooth scatternet with a Slave/Slave bridge is analyzed using the tools of queueing theory. We analyze two possible scheduling policies: limited service and exhaustive service, and derive analytical results for the probability distribution of access delay (i.e., the time that a packet has to wait before being serviced) and end-to-end delay for both intra- and inter-piconet bursty traffic. The exhaustive service discipline was found to provide lower values for all delay variables, over a wide range of parameter values. All analytical results have been confirmed through simulations.     

Optimization of the Scheduler for the Non-Blocking High-Capacity Router

The sequential greedy scheduling (SGS) is a scalable maximal matching algorithm that provides non-blocking in an Internet router with input buffers and a cross-bar. In this paper, we will present the FPGA design of the SGS scheduler. We have optimized scheduler components, and we will prove their correct functioning. The scheduler optimization significantly reduces the worst-case packet delay through the router.     

Case-based heuristic selection for timetabling problems

This paper presents a case-based heuristic selection approach for automated university course and exam timetabling. The method described in this paper is motivated by the goal of developing timetabling systems that are fundamentally more general than the current state of the art. Heuristics that worked well in previous similar situations are memorized in a case base and are retrieved for solving the problem in hand. Knowledge discovery techniques are employed in two distinct scenarios. Firstly, we model the problem and the problem solving situations along with specific heuristics for those problems. Secondly, we refine the case base and discard cases which prove to be non-useful in solving new problems. Experimental results are presented and analyzed. It is shown that case based reasoning can act effectively as an intelligent approach to learn which heuristics work well for particular timetabling situations. We conclude by outlining and discussing potential research issues in this critical area of knowledge discovery for different difficult timetabling problems.     

Simultaneous determination of halogenated derivatives of alkylphenol ethoxylates and their metabolites in sludges, river sediments, and surface, drinking, and wastewaters by liquid chromatography-mass spectrometry

A quantitative solid-phase extraction-liquid chromatography/mass spectrometry (SPE-LC/MS) method is described for the simultaneous analysis of halogenated byproducts of alkylphenolic compounds and their degradation products formed during chlorine disinfection in the presence of bromide ions. Compounds analyzed include brominated and chlorinated nonylphenol ethoxylates (XN-PEOs); octylphenol ethoxylates (XOPEOs); nonylphenols (XNP); nonylphenoxycarboxylates (XNPECs) and their precursors nonionic surfactants, alkylphenol ethoxylates (APEOs); and their metabolites formed during sewage treatment, alkylphenoxycarboxylates (APECs) and alkylphenols (APs). Target compounds were concentrated from water samples using a C18 SPE procedure. Extracts were analyzed using reversed phase LC/MS. The performances of both atmospheric pressure chemical ionization (APCI) and electrospray (ESI) interfaces were compared. ESI offered better sensitivity and specificity for a higher range of oligomers. Detection limits (LODs) for water samples were from 20 to 100 ng/L; and for sediment samples, from 2 to 10 microg/kg. Slightly higher LODs were obtained for sludge samples (5-25 microg/kg). Halogenated byproducts were found in sludge from Barcelona drinking water treatment plant in concentrations of 220 microg/kg for BrNP, 430 microg/kg for BrNPEOs (nEO = 1 - 2), and 1600 microg/kg for BrNPEOs (nEO = 3 - 15). The concentration of ClNPEOs was estimated to be in the order of 660 microg/kg (assuming the same response as BrNPEOs). Halogenated OPEOs were also identified, and their concentration was approximately 50 times lower than the concentration of NPEOs analogues. To our knowledge, this is the first method described that allows simultaneous determination of alkyphenol ethoxylates and halogenated derivatives, including degradation products.     

The products of YCF1 and YLL015w (BPT1) cooperate for the ATP-dependent vacuolar transport of unconjugated bilirubin in Saccharomyces cerevisiae

Since bilirubin-like pigments are present in the environment as degradation products of heme-containing proteins, yeast could have developed a detoxifying system to transport these compounds into their vacuoles. Vacuoles from Saccharomyces cerevisiae showed an ATP-dependent, saturative transport of unconjugated bilirubin (UCB) that was reduced by 60% and 40% in YCF1 and YLL015w-deleted cells, respectively; the double deletant showed no UCB uptake. Conversely, the transport of bile acids (taurocholate) was comparable in wild and deleted stains. These data identify YCF1 and YLL015w, named BPT1 (Bile Pigment Transporter), as the genes responsible for ATP-dependent UCB transport in yeast. Since YCF1 and YLL015w are rather homologous with multidrug resistant proteins (MRPs), they also suggest the involvement of this class of transporters in the ATP-dependent transport of unconjugated bilirubin.     

Entwicklung eines neuen Meridionalverfahrens für mehrstufige kompakte Axialverdichter und Validierung durch Experimente und CFD-Berechnungen

Development and validation of a universal through flow method applicable to design and analysis of compact multi-stage axial compressors will be described. Our method is based on correlations of the open literature which had been evaluated, selected and improved for this purpose. It contains a span wise mixing model to represent the 3D flow structure. For code validation various test cases are considered covering a wide range of application. Finally, the application of the method to analyse a newly-developed 11-stage gas turbine compressor will be demonstrated. The computed results have been compared with detailed test rig experiments. In addition, multi-stage steady-state computations were executed using a calibrated Navier-Stokes solver for 3D turbulent flows. Very good agreements of computed and measured results were achieved. In particular the through flow solver proves to be very accurate and fast in the prediction of compressor characteristics and has been directly used for optimisation of variable guide vane settings during the compressor test.     

Plant food by-products as feed: Characteristics,possibilities, environmental benefits,and negative sides

Modern society accumulates huge amounts of waste material, particularly in the food industry, where manipulation is usually inadequate and causes a serious ecological problem. As this state is unsustainable and a concern for the future, food by-products must be used as raw materials in further production, because they are often still rich in nutrients or bioactive compounds. This paper provides a comprehensive review of plant food by-product application in animal nutrition around the world. In addition, special attention is paid to ecological benefits, and warns about the potential hazards and negative sides of plant food by-products usage in animal nutrition.     

Photofate of oseltamivir (Tamiflu) and oseltamivir carboxylate under natural and simulated solar irradiation: kinetics, identification of the transformation products, and environmental occurrence

In this work the photodegradation pathways and rates of oseltamivir ester (OE) and oseltamivir carboxylate (OC) were studied under artificial and natural solar irradiation with the goal of assessing the potential of photolysis as a removal mechanism in aquatic environments. The structures of the photoproducts of OE, elucidated by ultra performance liquid chromatography-quadrupole-time-of-flight-mass spectrometry (UPLC-QToF-MS), were proposed to originate from hydration of the cyclohexene ring (TP330), ester hydrolysis (TP284), a combination thereof (TP302), intramolecular cyclization involving the ester (TP312), and cleavage of the ethylpropoxy side chain (TP226). The only photoproduct detected in case of OC was postulated to correspond to the hydration of the α,β-unsaturated acid (TP302). Under simulated solar irradiation the degradation rate of OC was approximately 10 times slower than that of OE, with half-lives ranging from 48 h in ultrapure water to 12 h in surface water from Sant Joan Despi, Llobregat river. The photodegradation under natural solar irradiation during the season of pandemic Influenza peak incidence was about 150 days for OC and 15 days for OE. In general, the photoproducts proved to be more resistant toward further photodegradation than the parent antivirals. In a monitoring survey of surface waters from the Ebro river (NE Spain), OC and OE were detected along with the photoproducts TP330 and 312.     

Circulating Endothelial Cells: A New Possible Marker of Endothelial Damage in Kawasaki Disease,Multisystem Inflammatory Syndrome in Children and Acute SARS-CoV-2 Infection

Background: Kawasaki Disease (KD) and Multisystem Inflammatory Syndrome in Children (MIS-C) are pediatric diseases characterized by systemic inflammation and vascular injury, potentially leading to coronary artery lesions (CALs). Data on vascular injury occurring during acute COVID-19 (AC19) in children are still lacking. The aim of our study was to investigate endothelial injury in KD-, MIS-C- and AC19-dosing circulating endothelial cells (CECs). Methods: We conducted a multicenter prospective study. CECs were enumerated by CellSearch technology through the immunomagnetic capture of CD146-positive cells from whole blood. Results: We enrolled 9 KD, 20 MIS-C and 10 AC19. During the acute stage, the AC19 and KD patients had higher CECs levels than the MIS-C patients. From the acute to subacute phase, a significant CEC increase was observed in the KD patients, while a mild decrease was detected in the MIS-C patients. Cellular clusters/syncytia were more common in the KD patients. No correlation between CECs and CALs were found in the MIS-C patients. The incidence of CALs in the KD group was too low to investigate this correlation. Conclusions: Our study suggests a possible role of CECs as biomarkers of systemic inflammation and endothelial dysfunction in KD and MIS-C and different mechanisms of vascular injury in these diseases. Further larger studies are needed.