New Method For Monitoring Research Articles

Caught in the Act: Direct Measurement of Protein Translocation across Membranes using Droplet Interface Bilayers

We introduce a new method for monitoring and quantitating the transport of materials across a model cell membrane. As a proof-of-concept, the cell-penetrating peptide, Pep-1, was used to carry horseradish peroxidase (HRP) across droplet-interface bilayers (DIBs). Two sub-microliter, lipid-encased aqueous droplets form a membrane at the contacting interface, through which enzyme-peptide complexes pass during transport. Following transport, the droplets are separated and the captured enzymes are assayed by a fluorogenic reaction. The DIB method recapitulates the findings of earlier studies involving Pep-1, including the dependence of protein transport on voltage and membrane charge, while also contributing new insights. Specifically, we found that leaflet charge symmetry may play a role in Pep-1-mediated protein translocation. We anticipate that the DIB method may be useful for a variety of transport-based studies, in particular those which must make use of tiny quantities of purified species.View Large Image | View Hi-Res Image | Download PowerPoint Slide

Control Loop Performance Assessment With a Dynamic Neuro-Fuzzy Model (dFasArt)

Most of the industrial controllers have some kind of performance problem. This feature is becoming more difficult to supervise and assess because of the increasing number of control loops of the processes. A new method for monitoring and performance assessment by using a neuro-fuzzy architecture is proposed. This method is based on the dFasArt model, which allows for a self-organizing classification (nonsupervised) of dynamic signals and building categories that can be easily interpreted in terms of fuzzy theory. A new fuzzy performance index (FPI) is defined, leading to a straight online assessment of the control loops. A great advantage compared with other techniques is that the method can be also applied to find relationships between process variables and to establish propagation paths. Other advantages of this method are as follows: 1) it is not necessary to obtain the model of the plant; 2) it can be applied online, in parallel with the process, without any dedicated experiment; and 3) the results are clearly presented to plant operator to help the control engineer to decide how to improve the control performance.

Direct Quantitation of Peptide-Mediated Protein Transport Across a Droplet Interface Bilayer

We introduce a new method for monitoring and quantitating the transport of materials across a model cell membrane. As a proof-of-concept, the cell-penetrating peptide, Pep-1, was used to carry horseradish peroxidase (HRP) across droplet-interface bilayers (DIBs). Two submicroliter, lipid-encased aqueous droplets form a membrane at the contacting interface, through which enzyme-peptide complexes pass during transport. Following transport, the droplets are separated and the captured enzymes are assayed by a fluorogenic reaction. The DIB method recapitulates the findings of earlier studies involving Pep-1, including the dependence of protein transport on voltage and membrane charge, while also contributing new insights. Specifically, we found that leaflet charge symmetry may play a role in Pep-1-mediated protein translocation. We anticipate that the DIB method may be useful for a variety of transport-based studies.

Optimizing vancomycin dosage regimen at the University Medical Center Maribor

BACKGROUND Vancomycin is a glycopeptide antibiotic used in the treatment of severe infections caused by Gram-positive bacteria. To lower the risk of antibiotic resistance, minimize toxic drug effects and to improve clinical effectiveness, it is recommended to monitor trough levels of vancomycin, with the desired range between 10–20 mg/l (15–20 mg/l for complicated infections). MATERIALS AND METHODS In the University Medical Center Maribor a new method for monitoring of vancomycin treatment has been accepted. Medical staff can adjust vancomycin dosage regimen using the pharmacokinetic program KINETIDEX ®. The aim of this study was to evaluate the usability of this program on a population of 28 patients treated with vancomycin in our hospital. After administration of the initial dosage regimen and measuring vancomycin trough level we – when necessary – suggested a new dosage regimen using KINETIDEX®. RESULTS The most common initial dosage regimen (23 out of 28 patients) was 1g/12h. Nine patients had an impaired renal function before vancomycin treatment, but only 4 of them received an adjusted initial dosage. In 9 patients a serum sample for determining trough concentration was obtained too early, when steady-state conditions had not been reached yet. Twenty out of 28 patients required adjustment of the initial vancomycin dosage regimen – 11 of them needed an increased daily dosage and 9 of them a lower daily dosage. In our research 23 patients out of 28 achieved the desired trough concentrations. In 14 out of 15 patients KINETIDEX® was able to predict a dosage regimen that resulted in the desired trough levels. One patient developed acute kidney failure after initiating vancomycin therapy. CONCLUSIONS Initial dosage regimen of vancomycin should be adjusted based on creatinine clearance − in clinical practice this is not always the case. Three-thirds of patients need modification of the initial vancomycin regimen. Clinical pharmacist can adjust dosage by using pharmacokinetic program KINETIDEX®. For effective dose adjustment of vancomycin, a serum sample should be obtained at appropriate time – just before the application of the next dose at steadystate conditions.

Direct Quantitation of Peptide-Mediated Protein Transport across a Droplet–Interface Bilayer

We introduce a new method for monitoring and quantitating the transport of materials across a model cell membrane. As a proof-of-concept, the cell-penetrating peptide, Pep-1, was used to carry horseradish peroxidase (HRP) across droplet-interface bilayers (DIBs). Two submicroliter, lipid-encased aqueous droplets form a membrane at the contacting interface, through which enzyme-peptide complexes pass during transport. Following transport, the droplets are separated and the captured enzymes are assayed by a fluorogenic reaction. The DIB method recapitulates the findings of earlier studies involving Pep-1, including the dependence of protein transport on voltage and membrane charge, while also contributing new insights. Specifically, we found that leaflet charge symmetry may play a role in Pep-1-mediated protein translocation. We anticipate that the DIB method may be useful for a variety of transport-based studies.

A new method for continuous monitoring of chest wall movement to characterize hypoxemic episodes during HFOV

Monitoring ventilated infants is difficult during high-frequency oscillatory ventilation (HFOV). This study tested the possible causes of hypoxemic episodes using a new method for monitoring chest wall movement during HFOV in newborn infants. Three miniature motion sensors were attached to both sides of the chest and to the epigastrium to measure the local tidal displacement (TDi) at each site. A >20% change in TDi was defined as deviation from baseline. Eight premature infants (postmenstrual age 30.6 ± 2.6 weeks) were monitored during 10 sessions (32.6 h) that included 21 hypoxemic events. Three types of such events were recognized: decrease in TDi that preceded hypoxemia (n = 11), simultaneous decrease in TDi and SpO2 (n = 6), and decrease in SpO(2) without changes in TDi (n = 4). In the first group, decreases in TDi were detected 22.4 ± 18.7 min before hypoxemia, and were due to airway obstruction by secretions or decline in lung compliance. The second group resulted from apnea or severe abdominal contractions. In the third group, hypoxia appeared following a decrease in FiO2. Monitoring TDi may enable early recognition of deteriorating ventilation during HFOV that eventually leads to hypoxemia. In about half of cases, hypoxemia is not due to slowly deteriorating ventilation.

A New Method for Monitoring and Forecasting the Case-Fatality Rate in Ongoing Epidemics and Its Evaluation Using Published Data of SARS in 2003, H1N1 Pandemic in 2009/2010, Hand-Foot-Mouth Disease in China in 2009/2010, and Cholera in Haiti in 2010

A New Method for Monitoring and Forecasting the Case-Fatality Rate in Ongoing Epidemics and Its Evaluation Using Published Data of SARS in 2003, H1N1 Pandemic in 2009/2010, Hand-Foot-Mouth Disease in China in 2009/2010, and Cholera in Haiti in 2010

Ice fraction assessment by near-infrared spectroscopy enhancing automated superchilling process lines

The objective of the current study was to analyze and develop some important automation steps in a superchilling process line. In order to control the product quality there is a need for online measurements of ice fraction and distribution in inhomogeneous products. Moreover, automatic handling of such superchilled products is currently commercially unavailable. The current study presents a new method for monitoring and handling superchilled product of varying form and consistency. Observation of the shift in the water absorption peak, measured by near-infrared spectroscopy (NIR) transflection mode, was used to determine the ice level in superchilled salmon, scanning approximately 1.5 cm into the fillets. The salmon fillets were stored on ice at 0 °C for 5–7 days before superchilling at −24 °C to target ice contents of 10%, 15% and 30%. Online NIR measurements of ice fraction showed promising results, with a low prediction error of 2.5%. The storage study confirmed former quality results with a microbiological shelf life of 15–17 days with only minor differences in values for drip loss and water-holding capacity between superchilled and chilled samples.

Abstract C241: Fine needle aspiration biopsy as a new method for monitoring of tumor microenvironment after treatment with polymeric drugs

Abstract Introduction: Cancer therapy seems to be, according to the latest findings, a combination of direct tumor cytotoxicity and the reaction of host immune system, which should become activated to successfully treat neoplastic disease. Monitoring time-dependent changes in composition of tumor infiltrating population of immunocompetent cells during the treatment could help to optimize therapeutic protocols and dosage. Water soluble polymeric conjugates based on N-(2-hydroxypropyl)-methacrylamide (HPMA) bearing anticancer drug doxorubicin bound through amide (DOX-HPMA-AM)) or hydrazone bond (DOX-HPMA-HYD) minimize unwanted side effects of conventional chemotherapy and thus enables much more aggressive treatment with very promising results. To analyze changes in tumor microenvironment during the treatment with such polymeric conjugates, we have used fine needle aspiration biopsy (FNAB). This is a commonly used clinical method to acquire samples from the body with minimal influence to tissues. It seems to be an ideal tool for gaining cell material repeatedly from one experimental animal during the treatment with simultaneous possibility to evaluate tumor growth and efficacy of used therapeutic protocol. Materials and Methods: C57BL/6 mice bearing EL4 T-lymphoma stably expressing Enhanced Green Fluorescent Protein (EL4-EGFP+) were treated with DOX-HPMA-AM, DOX-HPMA-HYD or free doxorubicin. FNAB was applied to isolate samples from EL4-EGFP+ tumors from mice treated with different drugs. All samples were stained with specific fluorescently labeled antibodies (CD3, CD4, CD8, CD45), analyzed by flow cytometry, and verified with the samples obtained from the tumor by excision. Also the tumor progression and survival of mice after FNAB were observed regular time distances. Results: The data obtained by FNAB or standard excision are comparable. Moreover, cell populations gained by FNAB method are more properly separated and contaminated with less debris. FNAB influences neither the tumor progression nor survival of experimental animals. Our data show that the number of tumor-infiltrating CD4 and CD8 lymphocytes increasing rapidly on third day after treatment with DOX-HPMA-AM and DOX-HPMA-HYD, while this treatment leads to complete recovery of neoplasma in all experimental animals. Contrary to this, free doxorubicin has no influence on composition of immunocompetent cells in tumor microenvironment and also no animal was able to recover from neoplastic disease. This fact suggests that both cytotoxic and immunomobilizing effect participate on tumor regression after treatment with HPMA conjugates. Citation Information: Mol Cancer Ther 2009;8(12 Suppl):C241.

Novel Reduction Kinetics Model of Dimethoate (DMA) on the Growth of Pseudomonas aeruginosa

A new method for monitoring Pseudomonas aeruginosa growth with dimethoate (DMA) as sole carbon using the series piezoelectric quartz crystal (SPQC) and high-performance liquid chromatography (HPLC) was described. Compared with the general methods, SPQC gives real-time, multidimensional information. The determination limit of HPLC was 1.08 ng. A combined novel response model for Pseudomonas aeruginosa degrading DMA was derived. By fitting DMA reducing data, the value of the reduction rate constant (k) was obtained and in line with the actual trend. The proposed kinetic model was successfully applied to Pseudomonas aeruginosa degrading DMA.

Optodynamic monitoring of laser micro-drilling of glass by using a laser probe

We present a new method for monitoring of the laser micro-drilling process. The method is based on detection of acoustic waves in air above the processed sample using a laser beam deflection probe (LBDP). We present an augmentation of the experimental set-up by means of a digital micrographic system which enables the acquisition of images of the plasma plume and of the hole cross-section during a drilling sequence. Comparing the acquired images with the detected LBDP signals, we examine the drilling process from a new perspective.

Multi-agent Coordinated Motion Planning for Monitoring and Controlling the Observed Space in a Security Zone

Monitoring and control of observed space in a security zone equipped with multi cameras and security robots are essential for efficient invader detection. For controlling the observed space, a coordinated motion planning technique is essential when a centralized motion planning solution is realized by a single supervisory system. This technique, however, is known to be very difficult to realize because concurrent multi-agent planning involves high computational complexity. We propose a new method for monitoring and controlling the observed space for a multi-agent security system with applicable computational burden. To identify time-varying observed space, two new tools, the extended overlap map (EOM) and the time-global surveillance coverage ratio graph (TGSG), are developed. Using these tools, we can properly monitor the time-varying observed space. In addition, to overcome the high complexity in the centralized motion planning, the priority is assigned to multi-agents. Finally, the observed space is monitored and controlled by planning multi-agents motions interactively using the EOM and the TGSG. The proposed method is then applied to conventional multi-agent security systems.

A NEW METHOD FOR MONITORING AND TUNING PLASTIC INJECTION MOLDING MACHINES

This paper presents a new method for monitoring and tuning plastic injection molding machines. It consists of two parts: quality monitoring using the Radial Basis Function Neural Network (RBFNN), and operation parameter tuning using Support Vector Machine (SVM) and Virtual Search Method (VSM). The quality is measured by the part weight, which is estimated using hydraulic pressure signal and ram position signals through a RBFNN. The tuning is aimed at finding the optimal setting of the machine operation condition. It is done in two steps: first, a SVM model is established as the virtual model to track the part quality variations, and then the quality variation is minimized by tuning the machine operating conditions using VSM. The new method is validated by two sets of practical experiments, and the results are very promising.

Non-invasive flow cytometric monitoring of pH i in cell culture processes using EGFP

We have described a new method for monitoring of cell culture processes using green fluorescent protein (GFP) fluorescent intensity. GFP has been used as a non-invasive fluorescent reporter for various cellular processes. In this study, enhanced (EGFP) was found to be a very sensitive indicator of pH i in in vitro cell culture, and responded rapidly to extracellular pH (pH e) changes. EGFP transfected cells were evaluated for pH i changes by flow cytometry, by measuring EGFP fluorescent intensity, and compared to that of the pH-sensitive fluoroprobe, SNARF. EGFP intensity was found to reflect pH i values of cells at different pH e in the presence of nigericin and was affected by the addition of HCl and NaOH. Significant changes in pH i were detected at different stages of batch culture and when using different cell density and media composition. The EGFP assay can be used to minimise the perturbation of cells and processes under study, thus leading to accurate information about the physiological state of single cells in a population. The results establish the application of EGFP as a non-invasive indicator of pH i for monitoring of mammalian cell culture processes.

Early Agglomeration Recognition System (EARS)

Abstract In fluidized-bed combustion and gasification of biomass and waste, agglomeration of bed/ash particles is a major problem area. This paper deals with a new method for monitoring and controlling fluidized-bed hydrodynamics, which enables the recognition of agglomeration in an early stage and provides control measures to prevent further agglomeration and defluidization. The method, called early agglomeration recognition system (EARS), is based on recognizing significant differences between reference time series of pressure fluctuations and successive time series measured during prolonged plant operation. The early recognition provides a time interval for taking dedicated actions to counteract the agglomeration. Thus, EARS can be a tool to help plant operators prevent agglomeration-induced plant shutdowns and minimize bed material makeup and residue production. Results are presented of small-scale experiments showing the effectiveness and selectivity of the early agglomeration recognition. Subsequently, the development of control strategies is discussed.

Fuzzy transition probability: a new method for monitoring progressive faults. Part 1: the theory

This paper presents a new method for condition monitoring, especially for monitoring progressive faults such as wear and fatigue. Based on the literature survey, the existing condition monitoring methods are based on either probability or fuzzy logic. The new method, called the fuzzy transition probability (FTP), combines the transition probability (Markov process) as well as the fuzzy set. From a theoretical point of view, the new method uses the available information from the training samples to the maximum extent (finding both the transition probability and the fuzzy membership) and hence, is more effective than the existing methods. This paper is the first part of a two-part paper. It presents the basic theory and shows how to compute the transition probability from the available training samples step by step. A simple demonstration example is also included. The second part of the paper presents two practical applications: one is material tensile strength testing and the other is tool condition monitoring in boring. Based on the testing results, the new method outperforms the popular artificial neural networks. Future research and applications are also discussed.

New method for monitoring of adsorption column saturation and regeneration II: on-line measurement

A new method suitable for the on-line monitoring of adsorption column saturation/regeneration cycles was developed based on the discovery that the electrical resistance of packed bed adsorbents changes dramatically upon adsorption and returns to its original value upon desorption. This change can be measured reliably and reproducibly. The two systems studied on-line in real time were methyl chloride (MeCl) adsorption on zeolite molecular sieve (HISIV 3000) and water vapour adsorption on basic alumina (RF-200). The sequential change in electrical readings at localized points within the column indicated the movement of the adsorption front, tracking the onset of breakthrough. The electrical readings returned to their original values upon desorption and the results were reproducible. Concurrently with the electrical measurements, the effluent gas of the MeCl/HISIV system was monitored for MeCl using an on-line gas chromatograph. An adsorption isotherm was created using the “length of unused bed” concept. The resistance change of the HISIV was found to be proportional to the square root of the amount of MeCl adsorbed, similarly to the C/CO 2 system discovered recently by our group. The universality of this correlation is being investigated. The simple measurement technique introduced here has the potential to improve the operating efficiency of industrial adsorption towers.

Monitoring the self-assembly of chitosan/glutaraldehyde/cysteamine/Au-colloid and the binding of human serum albumin with hesperidin

A new method for monitoring, in real-time, the self-assembly of chitosan/glutaraldehyde/cysteamine (CGC) on the gold surface and the immobilization of Au-colloid on CGC membrane with piezoelectric quartz crystal impedance (PQCI) are firstly proposed. Cyclic voltammogram and electrochemical impedance spectroscopy were also use to investigate the formation of Au-colloid/CGC. The viscosity-average molecular weight of chitosan used was firstly estimated as 16.8×10 5 with piezoelectric quartz crystal (PQC) sensor. On the basis of the analysis of the multi-dimensional information provided by PQCI, two stages existed in chitosan drying course: the frequency shift of the first stage was controlled by viscoelastic of the liquid, while the total frequency shift was due to mass change. The cross-link ratio of glutaraldehyde with chitosan was about 0.13, while for glutaraldehyde with cysteamine was about 0.217. PQCI also showed that the Au-colloid immobilization is a first-order reaction, while the HSA immobilization is a sum of two exponential functions, e.g., adsorption and re-arrangement. The association of the immobilized HSA with the purified hesperidin was monitored, and the association constant was estimated as 3.42 ml mg −1 by Scatchard analysis.

Determination of the metal complexation capacity of natural waters by ligand titration in the presence of complexing resins

The complexation properties of some drinking waters for U(VI), Al(III) and Cu(II) are determined by ligand titration (LT) with the metal ions, using a new method for monitoring, i.e. the sorpion of metal ion on complexing resins. The concentration of the free metal ion in solution is evaluated from the concentration of sorbed metal ion and from the quantity K * , which is the ratio of the concentration of the metal ion sorbed on the resin to the concentration of free metal ion in solution, and can be independently evaluated. The concentration of the ligands in solution (c I ) and the conditional stability constant (K M(I) ) are obtained by the Ruzic linearization. Different resins, i.e. the iminodiacetic resin Chelex 100, the carboxylic resin Amberlite CG 50 and the anion exchange resin AG1X8 were used for monitoring the titration, since they have different sorbing properties, and in principle they allow the detection of different ligands. Ligands at low concentration and with very high complexation constants were detected in the considered samples. Particularly in the case of U(VI), they are able to complex the metal ion much more strongly than the ligands that are usually considered in aqueous solution, i.e. carbonate and hydroxyl.

電気容量変化の交流周波数依存を用いたＣＦＲＰの成形モニタリング

Authors have developed an electric resistance change method for monitoring delaminations of CFRP laminates. The method employs reinforcement fibers as sensors, and the electrodes are co-cured. In the present study, the cocured electrodes are adopted as sensors for monitoring of degree of cure. The present study proposes a new method for monitoring of the degree of cure without embedding or attaching sensors on the basis of the electrical capacitance change. Applying alternating current during curing process between the electrodes provides dielectric properties of CFRP composites. As same as the conventional dielectric sensors for cure monitoring, the degree of cure of composites is monitored by means of measuring the dielectric constant of the composites here. The dielectric constant of the epoxy resin changes as the change of the frequency of the applied alternating current. Using the dependency of the applied alternating current of the dielectric constants, the degree of cure is directly measured without curve fitting and without cumbersome measurements with DSC. The proposed method is applied to a single ply CFRP and a multi-ply CFRP laminate here. As a result, the method shows excellent estimations of the degree of cure without additional sensors.