continuous operators
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We study the existence of continuous (linear) operators from the Banach spaces Lip 0 ( M ) of Lipschitz functions on infinite metric spaces M vanishing at a distinguished point and from their predual spaces F ( M ) onto certain Banach spaces, including C(K)-spaces and the spaces c 0 and ℓ 1 . For pairs of spaces Lip 0 ( M ) and C(K) we prove that if they are endowed with topologies weaker than the norm topology, then usually no continuous (linear or not) surjection exists between those spaces. It is also showed that if a metric space M contains a bilipschitz copy of the unit sphere S c 0 of the space c 0 , then Lip 0 ( M ) admits a continuous operator onto ℓ 1 and hence onto c 0 . Using this, we provide several conditions for a space M implying that Lip 0 ( M ) is not a Grothendieck space. Finally, we obtain a new characterization of the Schur property for Lipschitz-free spaces: a space F ( M ) has the Schur property if and only if for every complete discrete metric space N with cardinality d(M) the spaces F ( M ) and F ( N ) are weakly sequentially homeomorphic.
- Klíčová slova
- Grothendieck spaces, Lipschitz-free spaces, Spaces of Lipschitz functions, continuous operators, continuous surjections, density, weak topologies,
- Publikační typ
- časopisecké články MeSH
Continuous manufacturing is currently being seriously considered in the biopharmaceutical industry as the possible new paradigm for producing therapeutic proteins, due to production cost and product quality related benefits. In this study, a monoclonal antibody producing CHO cell line was cultured in perfusion mode and connected to a continuous affinity capture step. The reliable and stable integration of the two systems was enabled by suitable control loops, regulating the continuous volumetric flow and adapting the operating conditions of the capture process. For the latter, an at-line HPLC measurement of the harvest concentration subsequent to the bioreactor was combined with a mechanistic model of the capture chromatographic unit. Thereby, optimal buffer consumption and productivity throughout the process was realized while always maintaining a yield above the target value of 99%. Stable operation was achieved at three consecutive viable cell density set points (20, 60, and 40 × 106 cells/mL), together with consistent product quality in terms of aggregates, fragments, charge isoforms, and N-linked glycosylation. In addition, different values for these product quality attributes such as N-linked glycosylation, charge variants, and aggregate content were measured at the different steady states. As expected, the amount of released DNA and HCP was significantly reduced by the capture step for all considered upstream operating conditions. This study is exemplary for the potential of enhancing product quality control and modulation by integrated continuous manufacturing. Biotechnol. Bioeng. 2017;114: 298-307. © 2016 Wiley Periodicals, Inc.
- Klíčová slova
- continuous capture, integrated continuous biomanufacturing, monoclonal antibody, perfusion cell culture, product quality,
- MeSH
- bioreaktory MeSH
- buněčné kultury metody MeSH
- CHO buňky MeSH
- Cricetulus MeSH
- křečci praví MeSH
- monoklonální protilátky analýza izolace a purifikace metabolismus MeSH
- perfuze metody MeSH
- protein - isoformy chemie MeSH
- proteinové agregáty MeSH
- rekombinantní proteiny analýza izolace a purifikace metabolismus normy MeSH
- zvířata MeSH
- Check Tag
- křečci praví MeSH
- zvířata MeSH
- Publikační typ
- časopisecké články MeSH
- práce podpořená grantem MeSH
- Názvy látek
- monoklonální protilátky MeSH
- protein - isoformy MeSH
- proteinové agregáty MeSH
- rekombinantní proteiny MeSH
BACKGROUND AND AIMS: Obstructive sleep apnoea is a potentially serious sleep disorder associated with the risk of cardiovascular disease. It is treated with continuous airway pressure (CPAP) but this is not always successful. Unsuccessful cases should be treated by bilevel positive airway pressure (BiPAP). The aim of this study was to determine whether common respiratory parameters and/or body mass index (BMI) can be used to predict the probability CPAP failure and hence start such patients on BiPAP from the outset. METHODS: A sample of patients treated by CPAP for OSAS was evaluated a retrospective cohort study. The data measured in sleep monitoring of the successfully treated group and of the group where CPAP had failed were compared. Subsequently, the predictive abilities of BMI, Apnoea Index (AI), Apnoea-Hypopnea Index (AHI), percentage of sleep time in less than 90% oxygen saturation (T90), average oxygen saturation over the duration of sleep (SaO2) and average desaturation per hour of sleep (ODI) were assessed with respect to CPAP failure, both individually and in combination. RESULTS: A sample of 479 patients was included in the study. All of the recorded variables except AI were significantly associated with failure of CPAP and their ability to predict the failure ranged from poor to moderate. Since there was significant correlation among all the variables measured a two-variable prediction model combining T90 and BMI produced no significant improvement in the quality of CPAP failure prediction. CONCLUSIONS: BMI was a significant predictor of CPAP failure although it was slightly less predictive than T90. The set of monitored variables included in our study does not allow for CPAP failure to be predicted with clinically relevant reliability.
- Klíčová slova
- BMI, CPAP failure, obesity, prediction, sleep apnoea syndrome,
- MeSH
- index tělesné hmotnosti MeSH
- lidé středního věku MeSH
- lidé MeSH
- neúspěšná terapie MeSH
- obezita komplikace MeSH
- obstrukční spánková apnoe komplikace terapie MeSH
- plocha pod křivkou MeSH
- retrospektivní studie MeSH
- rizikové faktory MeSH
- ROC křivka MeSH
- trvalý přetlak v dýchacích cestách * MeSH
- Check Tag
- lidé středního věku MeSH
- lidé MeSH
- mužské pohlaví MeSH
- ženské pohlaví MeSH
- Publikační typ
- časopisecké články MeSH
- pozorovací studie MeSH
The author describes rehabilitation by means of CPM based on the principle of passive movement. This type of rehabilitation is used at the author's clinic after operations of the shoulder, elbow, hip and knee. The author describes her experience and the most frequent mistakes associated with the use of CPM. Advantages described in the literature regarding postoperative rehabilitation with CPM were confirmed at the author's clinic: intraarticular adhesions and stiff joints do not develop and the range of movements improves more rapidly.
- MeSH
- klouby chirurgie MeSH
- lidé MeSH
- pasivní pohybová terapie CPM * přístrojové vybavení metody MeSH
- pooperační péče MeSH
- Check Tag
- lidé MeSH
- Publikační typ
- anglický abstrakt MeSH
- časopisecké články MeSH
Devices for continuous passive motion, also known as motor-driven splints, are widely used in rehabilitation therapy following injuries and surgery. They present an adjunct method substituting the physical work of a physiotherapist. The method is indicated in early post-injury or post-operative periods. It is expected to increase blood drainage and remove haemarthrosis and synovial fluid exudate which precede an undesired development of granulation and fibrous tissues. However, continuing such an intensive therapy after 3 to 4 post-operative weeks lacks its raison d'être. The only exceptions include conditions after autologous chondrocyte transplantation and a supplementary therapy to active rehabilitation programmes for releasing muscle hypertonia which restricts movement. Values for the range of motion set up on the device cannot be considered the real values pertinent to the exercised joint; these are usually considerably lower. Key words: continuous passive motion, motor-driven splint.
Transferring an existing marketed pharmaceutical product from batch to continuous manufacturing (CM) without changes in regulatory registration is a challenging task in the pharmaceutical industry. Continuous manufacturing can provide an increased production rate and better equipment utilisation while retaining key quality attributes of the final product. Continuous manufacturing necessitates the monitoring of critical quality attributes in real time by appropriate process analytical tools such as near infra-red (NIR) probes. The present work reports a successful transfer of an existing drug product from batch to continuous manufacturing process without changing the formulation. A key step was continuous powder blending, whose design and operating parameters including weir type, agitation rate, dynamic hold-up and residence time were systematically investigated with respect to process repeatability. A NIR-based multivariate data model for in-line composition monitoring has been developed and validated against an existing quality control method for measuring tablet content uniformity. A continuous manufacturing long-run with a throughput of 30 kg/h (approx. 128,000 tablets per hour), uninterrupted for 320 min, has been performed to test and validate the multivariate data model as well as the batch to continuous process transfer. The final disintegration and dissolution properties of tablets manufactured by the continuous process were found to be equivalent to those manufactured by the original batch process.
- Klíčová slova
- Continuous manufacturing, Continuous powder blending, Direct compression, Near-infrared probe, Residence time,
- MeSH
- blízká infračervená spektroskopie metody MeSH
- farmaceutická chemie metody MeSH
- farmaceutická technologie * metody MeSH
- pomocné látky chemie MeSH
- prášky, zásypy, pudry chemie MeSH
- příprava léků metody MeSH
- řízení kvality MeSH
- rozpustnost MeSH
- tablety * MeSH
- uvolňování léčiv MeSH
- Publikační typ
- časopisecké články MeSH
- Názvy látek
- pomocné látky MeSH
- prášky, zásypy, pudry MeSH
- tablety * MeSH
Objective: To assess the plausibility of using the continuous glucose monitoring as a sole source of data for the screening of the neonatal hypoglycemia.Study design: Infants of mothers with diabetes were screened for neonatal hypoglycemia (less than 2.5 mmol/l after 4 h of life). Initial measurement was performed using point of care analyzer. We applied continuous glucose monitoring system subsequently. Infants were monitored up to 5 days or until discharge.Results: Out of 32 infants 11 had postnatal hypoglycemia resolved within 12 h of life. Two infants had hypoglycemia found due to continuous glucose monitoring after 24 h of life when sufficient feeding was established and they did not show any signs of hypoglycemia. We did not have any false negative measurements. No infant showed clinical signs of neonatal hypoglycemia.Conclusions: Continuous glucose monitoring is plausible and safe to use for screening of neonatal hypoglycemia. It operates well within the range that is accepted as safe for neurodevelopment. In addition, it can be used after first day of life where regular screening ends. Limitation of this method is possible alarm negligence of caregivers.
- Klíčová slova
- Continuous glucose monitoring, infants of diabetic mothers, neonatal hypoglycemia, screening,
- MeSH
- biologické markery krev MeSH
- hypoglykemie krev diagnóza MeSH
- krevní glukóza metabolismus MeSH
- lidé MeSH
- monitorování fyziologických funkcí metody MeSH
- novorozenec MeSH
- novorozenecký screening metody MeSH
- studie proveditelnosti MeSH
- těhotenství při diabetu * MeSH
- těhotenství MeSH
- Check Tag
- lidé MeSH
- mužské pohlaví MeSH
- novorozenec MeSH
- těhotenství MeSH
- ženské pohlaví MeSH
- Publikační typ
- časopisecké články MeSH
- klinické zkoušky MeSH
- Názvy látek
- biologické markery MeSH
- krevní glukóza MeSH
Clostridium acetobutylicum immobilised in polyvinylalcohol, lens-shaped hydrogel capsules (LentiKats(®)) was studied for production of butanol and other products of acetone-butanol-ethanol fermentation. After optimising the immobilisation protocol for anaerobic bacteria, continuous, repeated batch, and fed-batch fermentations in repeated batch mode were performed. Using glucose as a substrate, butanol productivity of 0.41 g/L/h and solvent productivity of 0.63 g/L/h were observed at a dilution rate of 0.05 h(-1) during continuous fermentation with a concentrated substrate (60 g/L). Through the process of repeated batch fermentation, the duration of fermentation was reduced from 27.8h (free-cell fermentation) to 3.3h (immobilised cells) with a solvent productivity of 0.77 g/L/h (butanol 0.57 g/L/h). The highest butanol and solvent productivities of 1.21 and 1.91 g/L/h were observed during fed-batch fermentation operated in repeated batch mode with yields of butanol (0.15 g/g) and solvents (0.24 g/g), respectively, produced per gram of glucose.
- Klíčová slova
- Butanol, Clostridium acetobutylicum, Fermentation, Immobilisation, LentiKats(®),
- MeSH
- aceton metabolismus MeSH
- anaerobióza MeSH
- butanoly metabolismus MeSH
- Clostridium acetobutylicum cytologie metabolismus MeSH
- ethanol metabolismus MeSH
- fermentace * MeSH
- imobilizované buňky metabolismus MeSH
- techniky vsádkové kultivace metody MeSH
- Publikační typ
- časopisecké články MeSH
- práce podpořená grantem MeSH
- Názvy látek
- aceton MeSH
- butanoly MeSH
- ethanol MeSH
In this note the two dimensional Dirac operator A η with an electrostatic δ -shell interaction of strength η ∈ R supported on a straight line is studied. We observe a spectral transition in the sense that for the critical interaction strengths η = ± 2 the continuous spectrum of A η inside the spectral gap of the free Dirac operator A 0 collapses abruptly to a single point.
- Klíčová slova
- Boundary triple, Dirac operator, Singular potential, Spectral transition,
- Publikační typ
- časopisecké články MeSH
Temperature control in continuous stirred tank heater (CSTH) systems is essential for ensuring energy efficiency, safety, and product quality in industrial processes. However, the nonlinear dynamics and external disturbances make conventional proportional-integral-derivative (PID) control inadequate for reliable operation. This study presents a novel two-degrees-of-freedom PID (2DoF-PID) controller optimized using the quadratic interpolation optimization (QIO) algorithm to enhance CSTH temperature regulation. The QIO-based approach allows independent tuning for setpoint tracking and disturbance rejection, overcoming the limitations of classical PID controllers. Extensive nonlinear time-domain simulations, reference tracking, and disturbance rejection tests demonstrate the superior performance of the proposed controller in terms of reduced overshoot, faster settling time, and minimal steady-state error. Furthermore, comparative evaluations with traditional tuning methods (Murrill and Rovira) and several state-of-the-art metaheuristic optimizers (DE, PSO, FLA, MGO) validate the effectiveness and robustness of the QIO-optimized strategy. This work introduces a pioneering application of the QIO algorithm in industrial temperature control, offering a scalable and cost-efficient solution for complex nonlinear systems.
