148 research outputs found
Modeling and Control of Maximum Pressure Rise Rate in RCCI Engines
Low Temperature Combustion (LTC) is a combustion strategy that burns fuel at lower temperatures and leaner mixtures in order to achieve high efficiency and near zero NOx emissions. Since the combustion happens at lower temperatures it inhibits the formation of NOx and soot emissions. One such strategy is Reactivity Controlled Compression Ignition (RCCI). One characteristic of RCCI combustion and LTC com- bustion in general is short burn durations which leads to high Pressure Rise Rates (PRR). This limits the operation of these engines to lower loads as at high loads, the Maximum Pressure Rise Rate (MPRR) hinders the use of this combustion strategy.
This thesis focuses on the development of a model based controller that can control the Crank Angle for 50% mass fraction burn (CA50) and Indicated Mean Effective Pressure (IMEP) of an RCCI engine while limiting the MPRR to a pre determined limit. A Control Oriented Model (COM) is developed to predict the MPRR in an RCCI engine. This COM is then validated against experimental data. A statistical analysis of the experimental data is conducted to understand the accuracy of the COM. The results show that the COM is able to predict the MPRR with reasonable accuracy in steady state and transient conditions. Also, the COM is able to capture the trends during transient operation. This COM is then included in an existing cycle by cycle dynamic RCCI engine model and used to develop a Linear Parameter
Varying (LPV) representation of an RCCI engine using Data Driven Modeling (DDM) approach with Support Vector Machines (SVM). This LPV representation is then used along with a Model Predictive Controller (MPC) to control the CA50 and IMEP of the RCCI engine model while limiting the MPRR. The controller was able to track the desired CA50 and IMEP with a mean error of 0.9 CAD and 4.7 KPa respectively while maintaining the MPRR below 5.8 bar/CAD
Iron Deficiency Anaemia and Anaemia of Inflammation in Enteropathies Caused by Commonest Small Intestine Disorders: Current Evidence
Funding Information: Heartfelt thanks to Verina Wild and Stephen Latham for comments on early drafts. Publisher Copyright: Β© 2022 Olesja Basina et al., published by Sciendo.It is no mystery that iron deficiency is the most common anaemia and multiple studies have shown that anaemia is a main factor for decreased quality of life. The focus of our article is an up-to-date review of different enteropathies caused by specific disorders and the prevalence of iron deficiency anaemia (IDA), starting with the understanding of physiology of iron absorption and regulation in the intestine. The pathologies that we tried to cover were celiac disease, Crohnβs disease, nonsteroidal anti-inflammatory drugs (NSAID)-induced enteropathy and protein losing enteropathy. Unfortunately, not everything still understood and questions still remain. The main questions are associated with our understanding of iron regulation beyond the ferroportin-hepcidin axis and what mechanism is behind changes of epithelium in different conditions. Depending on the study and pathology of enteropathy, almost half of the studied patients had iron deficiency anaemia. However, in all enteropathies, IDA is more an additional finding or an additional symptom that needs further investigations. That is why many authors consider that IDA is caused by secondary mechanisms and not enteropathy per se and should be correlating with undernourishment, severe mucosal atrophy, malabsorption, and bleeding.publishersversionPeer reviewe
Π§Π΅Π»ΠΎΠ²Π΅ΡΠ΅ΡΡΠ²ΠΎ. ΠΠ΅ΡΡΠ°Π½Π΄Π°ΡΡΠ½ΡΠ΅ ΠΌΠΎΠ΄Π΅Π»ΠΈ
It is described the first results of the usage of the proposed by the authors information-wave theory of the interacting systems for the humanity investigation as a complex self-organizing system within the synergetic paradigm. It is determined the βunit complex parameterβ, characterizing the humanity as a unit system; its change dynamics is studied. It is proposed a new model for the growth dynamics of the complex unit parameter and it is given the previous information interpretation of the imaginary part of this complex parameter. It is constructed the chains of the threefold elements, which characterize the main parameters, determining the human society dynamics, and these parameters measures are proposed. It is made the first attempt of investigation of the boundaries influence on the human population dynamics.Π Π½Π°ΡΡΠΎΡΡΠ΅ΠΉ ΡΠ°Π±ΠΎΡΠ΅ ΠΈΠ·Π»Π°Π³Π°ΡΡΡΡ ΠΏΠ΅ΡΠ²ΡΠ΅ ΡΠ΅Π·ΡΠ»ΡΡΠ°ΡΡ ΠΏΡΠΈΠ»ΠΎΠΆΠ΅Π½ΠΈΡ ΡΠ°Π·ΡΠ°Π±Π°ΡΡΠ²Π°Π΅ΠΌΠΎΠΉ Π°Π²ΡΠΎΡΠ°ΠΌΠΈ Π² ΡΠ°ΠΌΠΊΠ°Ρ
ΡΠΈΠ½Π΅ΡΠ³Π΅ΡΠΈΡΠ΅ΡΠΊΠΎΠΉ ΠΏΠ°ΡΠ°Π΄ΠΈΠ³ΠΌΡ ΠΈΠ½ΡΠΎΡΠΌΠ°ΡΠΈΠΎΠ½Π½ΠΎ-Π²ΠΎΠ»Π½ΠΎΠ²ΠΎΠΉ ΡΠ΅ΠΎΡΠΈΠΈ Π²Π·Π°ΠΈΠΌΠΎΠ΄Π΅ΠΉΡΡΠ²ΠΈΡ ΡΡΡΡΠΊΡΡΡ ΠΈ ΡΠΈΡΡΠ΅ΠΌ ΠΊ ΠΈΡΡΠ»Π΅Π΄ΠΎΠ²Π°Π½ΠΈΡ ΡΠ΅Π»ΠΎΠ²Π΅ΡΠ΅ΡΡΠ²Π° ΠΊΠ°ΠΊ ΡΠ»ΠΎΠΆΠ½ΠΎΠΉ ΡΠ°ΠΌΠΎΠΎΡΠ³Π°Π½ΠΈΠ·ΡΡΡΠ΅ΠΉΡΡ ΡΠΈΡΡΠ΅ΠΌΡ. ΠΡΠΏΠΎΠ»Π½Π΅Π½ ΠΏΡΠ΅Π΄Π²Π°ΡΠΈΡΠ΅Π»ΡΠ½ΡΠΉ Π»ΠΈΠ½Π³Π²ΠΈΡΡΠΈΡΠ΅ΡΠΊΠΈΠΉ Π°Π½Π°Π»ΠΈΠ· ΡΠ»ΠΎΠ² Β«ΡΠ΅Π»ΠΎΠ²Π΅ΠΊΒ» ΠΈ Β«ΡΠ΅Π»ΠΎΠ²Π΅ΡΠ΅ΡΡΠ²ΠΎΒ». ΠΠΏΡΠ΅Π΄Π΅Π»ΡΠ½ Β«ΠΊΠΎΠΌΠΏΠ»Π΅ΠΊΡΠ½ΡΠΉ ΠΏΠ°ΡΠ°ΠΌΠ΅ΡΡ ΡΠ΅Π»ΠΎΠ³ΠΎΒ», Ρ
Π°ΡΠ°ΠΊΡΠ΅ΡΠΈΠ·ΡΡΡΠΈΠΉ ΡΠ΅Π»ΠΎΠ²Π΅ΡΠ΅ΡΡΠ²ΠΎ ΠΊΠ°ΠΊ Π΅Π΄ΠΈΠ½ΡΡ ΡΠΈΡΡΠ΅ΠΌΡ, ΠΈ ΠΈΡΡΠ»Π΅Π΄ΠΎΠ²Π°Π½Π° Π΄ΠΈΠ½Π°ΠΌΠΈΠΊΠ° Π΅Π³ΠΎ ΠΈΠ·ΠΌΠ΅Π½Π΅Π½ΠΈΡ. ΠΡΠ΅Π΄Π»ΠΎΠΆΠ΅Π½Π° Π½ΠΎΠ²Π°Ρ ΠΌΠΎΠ΄Π΅Π»Ρ Π΄ΠΈΠ½Π°ΠΌΠΈΠΊΠΈ ΡΠΎΡΡΠ° ΠΊΠΎΠΌΠΏΠ»Π΅ΠΊΡΠ½ΠΎΠ³ΠΎ ΠΏΠ°ΡΠ°ΠΌΠ΅ΡΡΠ° ΡΠ΅Π»ΠΎΠ³ΠΎ ΠΈ Π΄Π°Π½Π° ΠΏΡΠ΅Π΄Π²Π°ΡΠΈΡΠ΅Π»ΡΠ½Π°Ρ ΠΈΠ½ΡΠΎΡΠΌΠ°ΡΠΈΠΎΠ½Π½Π°Ρ ΠΈΠ½ΡΠ΅ΡΠΏΡΠ΅ΡΠ°ΡΠΈΡ ΠΌΠ½ΠΈΠΌΠΎΠΉ ΡΠ°ΡΡΠΈ ΡΡΠΎΠ³ΠΎ ΠΊΠΎΠΌΠΏΠ»Π΅ΠΊΡΠ½ΠΎΠ³ΠΎ ΠΏΠ°ΡΠ°ΠΌΠ΅ΡΡΠ°. ΠΠΎΡΡΡΠΎΠ΅Π½Π° ΡΠ΅ΠΏΠΎΡΠΊΠ° ΡΡΠΈΠ°Π΄, ΡΠ»Π΅ΠΌΠ΅Π½ΡΡ ΠΊΠΎΡΠΎΡΡΡ
Ρ
Π°ΡΠ°ΠΊΡΠ΅ΡΠΈΠ·ΡΡΡ ΠΎΡΠ½ΠΎΠ²Π½ΡΠ΅ ΠΏΠ°ΡΠ°ΠΌΠ΅ΡΡΡ, ΠΎΠΏΡΠ΅Π΄Π΅Π»ΡΡΡΠΈΠ΅ Π΄ΠΈΠ½Π°ΠΌΠΈΠΊΡ ΡΠ΅Π»ΠΎΠ²Π΅ΡΠ΅ΡΠΊΠΎΠ³ΠΎ ΠΎΠ±ΡΠ΅ΡΡΠ²Π°, ΠΈ ΠΏΡΠ΅Π΄Π»ΠΎΠΆΠ΅Π½Ρ ΠΈΠ·ΠΌΠ΅ΡΠΈΡΠ΅Π»ΠΈ ΡΡΠΈΡ
ΠΏΠ°ΡΠ°ΠΌΠ΅ΡΡΠΎΠ². Π‘Π΄Π΅Π»Π°Π½Π° ΠΏΠ΅ΡΠ²Π°Ρ ΠΏΠΎΠΏΡΡΠΊΠ° ΠΈΠ·ΡΡΠ΅Π½ΠΈΡ Π²Π»ΠΈΡΠ½ΠΈΡ Π³ΡΠ°Π½ΠΈΡ Π½Π° Π΄ΠΈΠ½Π°ΠΌΠΈΠΊΡ ΡΠ΅Π»ΠΎΠ²Π΅ΡΠ΅ΡΠΊΠΎΠΉ ΠΏΠΎΠΏΡΠ»ΡΡΠΈΠΈ
Adsorption and gas sensing properties of CuFe2O4 nanoparticles
Spinel ferrite nanoparticles in the form CuFe2O4 were tested for gas sensing applications. Nanoparticles pressed in a disk form were used to construct conductometric gas sensors. The disk was placed between two electrical electrodes wherein the top electrode had a grid structure. The produced sensors were tested against H2S and H2 gases and they were found to be selective and sensitive to H2S concentration as low as 25 ppm. The composition of the nanoparticles was confirmed by X-ray diffraction and energy dispersive X-ray spectroscopy measurements. The crystal structure was verified by both X-ray diffraction and transmission electron microscope. The observations obtained from the experiments demonstrated the high potential of using CuFe2O4 nanoparticles for H2S sensing applications.This work was supported by the Khalifa University under the Grant Number RIFP-14312 and the Qatar University under the Grant Number QUCG-CAS-2018\2019-1.Scopu
Could really systemic inflammatory markers be predictors of COPD Progression
Inflammatory biomarkers are considered by modern researchers as one of the best markers of effectiveness of inhaled corticosteroids (ICS) at patients with COPD, but there are a few studies about their prediction opportunity for COPD progression. The study is devoted to study of the diagnostic value of some markers of systemic inflammation (CRP, fibrinogen, MMP-2 and -9, hyaluronic acid (HA) at patients with COPD, there role as predictors of COPD progression. It was determined that determination of dynamic levels of such marker of systemic inflammation as
MMP-2, CRP, HA can be used as parameters for further evaluation of the clinical stability of patients during their long-term follow-up. Significant decreasing of inflammatory markers shows the adequacy of anti-inflammatory therapy of patients with COPD regardless of changes in lung function dynamic disorders
H<sub>2</sub>S removal by copper enriched porous carbon cuboids
Hydrogen sulfide (H2S) removal by adsorption from gas streams is crucial to prevent the environmental and industrial damage it causes. Amongst the nanostructures considered excellent candidates as sorbents, porous carbon has been studied extensively over the last years. In the present work we present a synthetic procedure for three high potential sorbents based on carbon cuboids, namely a low-surface-area copper-rich structure, a highly porous aggregate without metal addition, and lastly the same porous carbon decorated with copper. The properties and performance as catalysts of these three sorbents were evaluated by powder X-ray diffraction, X-ray photoelectron spectroscopy, thermal analysis, scanning electron microscopy with energy dispersive X-ray analysis, surface area determination through N2 adsorption and desorption, as well as by H2S adsorption measurements
Diagnostic and Prognostic value of Hyaluronic acid at patients with COPD
Chronic inflammation and airway remodeling are characteristics of chronic obstructive pulmonary disease (COPD). Abnormalities in hyaluronic acid, a component of the extracellular matrix, may be involved in the pathogenesis of COPD. But there are no researchers about its role like a marker of effectiveness of anti-inflammatory therapy (AIT) at patients with COPD. The study is devoted to the diagnostic value of HA at patients with COPD, the role of the HA as a marker of the effectiveness of AIT at patients with COPD. It was determined that the level of HA at patients with COPD before AIT was significantly higher than it at patients of the control group. But in 3 months after correction of treatment the level of HA decreased significantly at all patients comparing to previous visit, which corresponded to the level of the control group. It means that the significant decreasing of HA level at patients with COPD may be a marker of the effectiveness of AIT
Diagnostic and prognostic role of matrix metalloproteinases in patients with chronic obstructive pulmonary disease
In GOLD 2017 updated report was pointed that lung function level does not depend on patientsβ categoryof future risk. That is why continuing of COPD additional risk precursors discussion is still actual.COPD is associated with increased numbers of inflammatory cells and fibroblasts and the up-regulationof proteases such as matrix metalloproteinases (MMPs) resulting in fibrosis of small airways anddestruction of the parenchyma. But these markers also constitute innovative direct or indirect targets tomodify cardiovascular tissue remodelling in atherosclerosis and heart failure. That is why it is importantto understand could really MMP-2 and MMP-9 be markers of bronchial inflammation including patientswith COPD.The aim of our work was to determine the role of initial and dynamic levels of inflammatory markersMMP-2 and MMP-9 as indicators of COPD severity, stability and treatment effectiveness.We observe patients with verified stable COPD. The levels of MMP-2 and -9 in plasma were determinedby ELISA. Investigations were done firstly on screening (visit 1). Then correction of basic antiinflammatorytreatment was done according to national and European guidelines. Repeated studies weredone on visit 2 (after 3 months of basic treatment), on visit 3 (after 6 months of basic treatment), on visit4 (after 12 months of regular basic treatment). Comparison group was patients with verified cardiacdisease. Control group was healthy people).In general levels of inflammatory markers MMP-2 and MMP-9 in COPD patients on visit 1 weresignificantly higher than in control group, but in subgroups they were almost identical. After 3 months ofadequate treatment level of MMP-2 dropped slightly, kept at this level for six months, and in one year itdecreased significantly and reached the level of the control group. On the base of regular treatment bothMMP-2 and MMP-9 decreased from visit to visit and after 12 month they have been normalized. Thisfact indicates that these markers could be parameters of effective basic treatment in patients with COPD.Increasing of such inflammatory biomarkers as MMP-2 and MMP-9 are useful index of COPD whichindicates on needing of regular basic treatment and dynamic decreasing and normalizing of MMP-2 andMMP-9 during basic treatment are signs of successful therapy during their long-term follow-up
Pulmonary embolism in the therapeutic practice, riskassessment on the example of clinical case
Pulmonary embolism (PE) is a βgreat imitatorβ and the symptoms of the disease are nonspecific, besidesthere is a lack of alertness of doctors and patients in terms of the development of this terriblecomplication. The aim of our work is to assess the risk of PE developing in patients of the therapeuticprofile, to identify patients at high risk for determining direct sources of thrombosis and to analyze themost significant factors that can lead to errors in the diagnosis of PE on the example of a clinical casewith an unfavorable outcome.Totally 78 patients were examined. A study of hospitalized patients with a therapeutic profile using theGeneva and Wells scales revealed a high risk of PE in 6,4% of cases. In the high-risk group with the helpof additional survey methods, there was a direct threat of PE development and in two cases PE of smallbranches was confirmed.Analyzing one clinical case it is worth to remark such reasons for the late diagnosis of PE and anunfavorable outcome as acute leg injury and the presence of DVT, low compliance with the patient, lackof alertness in PE development during hospitalization, unpredictable case anamnesis, reassessment ofadditional studies (CT) conclusion, late appointment of methods for diagnosing of the localization andmassiveness of PE
Pneumonia misdiagnosis. Are we loosing time?
Community-acquired pneumonia (CAP) is not only one of the most frequent lower respiratory tractinfectious but also one of the most misdiagnosed. There is no clear data in Ukraine on the incidence ofCAP misdiagnosis and conditions, which can be difficult to differ with it. Therefore, we carried out astudy of case histories of patient with CAP and identified three cases of pneumonia misdiagnosis withlethal outcomes. One of them is presented in the article to demonstrate clinical diversity that can lead tountimely diagnosis of diseases hiding under initially suspected CAP
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