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The novel, automated, multi-pumping flow system (MPFS) for online calibration and determination of nitrate in surface water is presented for the first time. The system was equipped with micropumps of three different nominal volumes (10, 20, and 50 µL). As a result, it was possible to prepare from one standard, directly in a flow system, up to seven standard solutions. Determination of nitrate was conducted in stop-flow conditions and is based on a commercially available ion selective electrode (ISE) application. It was found that the linearity and slope of the calibration graphs depend mainly on the characteristics of the ISE. The obtained results were very repeatable, owing to the high precision of the micro-pumps used. The R.S.D. for the stroke volume of each micro-pump was below 1%. The accuracy of the method was checked through determination of nitrate in surface water samples. The obtained results were compared with those of the reference method (photometric Hach cuvette tests). It was found that, at a 96% confidence level, the difference between the results obtained by the proposed method and the reference method was statistically insignificant. The accuracy of the method was confirmed through the determination of nitrate in Certified Reference Material. The relative deviation (R.D.) of the measured and the certified concentrations was 5%.

Glucokinase (GK) is a key regulator of glucose homeostasis, and its small-molecule activators represent a promising opportunity for the treatment of type 2 diabetes. Several GK activators have been advanced into clinical trials and have demonstrated promising efficacy; however, hypoglycemia represents a key risk for this mechanism. In an effort to mitigate this hypoglycemia risk while maintaining the efficacy of the GK mechanism, we have investigated a series of amino heteroaryl phosphonate benzamides as ''partial" GK activators. The structure-activity relationship studies starting from a "full GK activator" 11 , which culminated in the discovery of the "partial GK activator" 31 (BMS-820132), are discussed. The synthesis and in vitro and in vivo preclinical pharmacology profiles of 31 and its pharmacokinetics (PK) are described. Based on its promising in vivo efficacy and preclinical ADME and safety profiles, 31 was advanced into human clinical trials.

The main research question concerned the identification of changes in the COVID-19 epidemiological situation using fuzzy clustering methods. This research used cross-sectional time series data obtained from the European Centre for Disease Prevention and Control. The identification of country types in terms of epidemiological risk was carried out using the fuzzy c-means clustering method. We also used the entropy index to measure the degree of fuzziness in the classification and evaluate the uncertainty of epidemiological states. The proposed approach allowed us to identify countries' epidemic states. Moreover, it also made it possible to determine the time of transition from one state to another, as well as to observe fluctuations during changes of state. Three COVID-19 epidemic states were identified in Europe, i.e., stabilisation, destabilisation, and expansion. The methodology is universal and can also be useful for other countries, as well as the research results being important for governments, politicians and other policy-makers working to mitigate the effects of the COVID-19 pandemic.

Novel integrated flow-based steam distillation and titration system with spectrophotometric detection was developed for determination of volatile acidity in wines. Using the system, the distillation procedure was carried out in an automatic manner, starting with introducing into a heated steam distillation module a sample and subjecting it to steam distillation. Under selected conditions, all the analyte was transferred to the distillate; therefore, the system did not require calibration. The collected distillate and titrant were introduced into the next monosegments in varying proportions, in accordance with the developed titration procedure, and directed to the detection system to record the titration curve. The titration was stopped after reaching the end point of titration. Procedures for distillation and titration were developed and verified separately by distillation of acetic acid, acetic acid in the presence of tartaric acid as well as acetic acid, tartaric acid, and titratable acidity, with precision (relative standard deviation) and accuracy (relative error) for both procedures lower than 6.9 and 5.6%, respectively. The developed steam distillation and titration systems were used to determine volatile acidity in samples of white and rosé wines separately and as the integrated steam distillation and titration system, both with precision lower than 9.4% and accuracy better than 6.7%.

The purpose of this paper is to assess the level of material deprivation in European Union countries in 2016 from both a local and a global perspective. The Technique for Order Preference by Similarity to an Ideal Solution (TOPSIS) was used in the study. Based on research, five main types of the level of the material deprivation of European Union countries were identified. Research findings suggest that the population of old EU countries is less severely affected by material deprivation than people living in new member states. Also, the level of global material deprivation was assessed. The study was based on 2016 statistical data delivered by Eurostat., Competing Interests: NO authors have competing interests.

A preconcentration module operated in flow mode and integrated with a sequential injection system with spectrophotometric detection was developed. Using the system, preconcentration was performed in continuous mode and was based on a membraneless evaporation process under diminished pressure. The parameters of the proposed system were optimized and the system was tested on the example of the spectrophotometric determination of Cr(III). The preconcentration effectiveness was determined using the signal enhancement factor. In the optimized conditions for Cr(III), it was possible to obtain the signal enhancement factors of around 10 (SD: 0.9, n = 4) and determine Cr(III) with precision and intermediate precision of 8.4 and 5.1% (CV), respectively. Depending on the initial sample volume, signal enhancement factor values of about 20 were achieved. Applicability of the developed preconcentration system was verified in combination with the capillary electrophoresis method with spectrophotometric detection on the example of determination of Zn in certified reference materials of drinking water and wastewater. Taking into account the enhancement factor of 10, a detection limit of 0.025 mg L -1 was obtained for Zn determination. Zn was determined with precision less than 6% (CV) and the results were consistent with the certified values.

Background: Physical activity is a complex behavior that is difficult to measure validly and reliably in large, population-based studies. Data on physical activity are available for the initial 100,000 participants of the German National Cohort., Objectives: To describe the baseline physical activity assessment in the cohort and to present initial descriptive results., Material and Methods: Physical activity was assessed using a combination of tools, including two self-administered questionnaires, the Questionnaire on Annual Physical Activity Pattern (QUAP) and the Global Physical Activity Questionnaire (GPAQ); a computer-based 24‑h physical activity recall (cpar24); and 7‑day accelerometry (Actigraph GT3X/+; ActiGraph, Pensacola, FL, USA)., Results: The availability of data varied between assessment instruments (QUAP: n = 16,372; GPAQ: n = 90,900; cpar24: n = 23,989; accelerometry: n = 35,218). Analyses across measurement tools showed that on average, women spent 75 to 216 min/d, and men spent 73 to 224 min/d in moderate or higher intensity total physical activity. Persons aged 20-39 years spent 66 to 200 min/d, and persons aged 40-69 years spent 78 to 244 min/d in moderate or higher intensity total physical activity., Conclusions: Initial baseline analyses of physical activity in this cohort show the value of using a combination of questionnaires, 24‑h recalls, and a movement sensor. The comprehensive data collection represents a valuable resource for future analyses and will improve our understanding of the association between physical activity and disease prevention.

Physical fitness is defined as an individual's ability to be physically active. The main components are cardiorespiratory fitness (CRF), muscle strength, and flexibility. Regardless of physical activity level, physical fitness is an important determinant of morbidity and mortality.The aim of the current study was to describe the physical fitness assessment methodology in the German National Cohort (NAKO) and to present initial descriptive results in a subsample of the cohort.In the NAKO, hand grip strength (GS) and CRF as physical fitness components were assessed at baseline using a hand dynamometer and a submaximal bicycle ergometer test, respectively. Maximum oxygen uptake (VO 2max ) was estimated as a result of the bicycle ergometer test. The results of a total of 99,068 GS measurements and 3094 CRF measurements are based on a data set at halftime of the NAKO baseline survey (age 20-73 years, 47% men).Males showed higher values of physical fitness compared to women (males: GS = 47.8 kg, VO 2max  = 36.4 ml·min -1  · kg -1 ; females: GS = 29.9 kg, VO 2max  = 32.3 ml · min -1  · kg -1 ). GS declined from the age of 50 onwards, whereas VO 2max levels decreased continuously between the age groups of 20-29 and ≥60 years. GS and VO 2max showed a linear positive association after adjustment for body weight (males β = 0.21; females β = 0.35).These results indicate that the physical fitness measured in the NAKO are comparable to other population-based studies. Future analyses in this study will focus on examining the independent relations of GS and CRF with risk of morbidity and mortality.

The aim of this study was to analyze the impact of being pain-affected and fear of falling on functional performance among nursing home residents, longitudinally. We used 6-month follow-up data from a cluster-randomized trial of 12 nursing homes (cluster level) with 239 nursing home residents at baseline (mean age, 95% confidence interval [CI] = 83.04 [81.40, 84.69], 70% women). The longitudinal analysis provided data on pain, fear of falling, functional mobility, and activities of daily living (individual level). The data revealed a trend indicating that pain-relieved nursing home residents showed better functional mobility over time. The results on fear of falling demonstrate obvious differences in the functional performance of nursing home residents cross-sectionally but not longitudinally. Nevertheless, the results underline the importance of an effective pain treatment to prevent decline in functional mobility among nursing home residents. Further longitudinal surveys are needed to verify the findings on functional performance.

An automated and miniaturized chemiluminescence method for screening of fluoroquinolones in milk samples was proposed. The method was based on magnetic dispersive micro-solid phase extraction of analytes followed by the chemiluminescence determination of the total fluoroquinolones content using a multi-pumping flow system. In the developed method, Zr-Fe-C magnetic nanoparticles were used as an efficient sorbent for separation of fluoroquinolones from sample matrix. The chemiluminescence intensity obtained for Ce 4+ -SO 3 2- -Tb 3+ chemiluminescence system was greatly increased in the presence of the analytes. Under the optimal conditions, the detector response for fluoroquinolones was linear in the concentration ranges from 5·10 -9 to 1·10 -6  mol L -1 with respect to fleroxacin. The limit of detection, calculated from a blank test based on 3σ, was 2·10 -9  mol L -1 with respect to fleroxacin. The presented method demonstrated to be a good tool for available and cost-effective point-of-need screening fluoroquinolones in milk samples., (Copyright © 2018 Elsevier Ltd. All rights reserved.)

We show that one-dimensional (1d) GaN quantum-wires (QWRs) exhibit intense and spectrally sharp emission lines. These QWRs are realized in an entirely self-assembled growth process by molecular beam epitaxy (MBE) on the side facets of GaN/AlN nanowire (NW) heterostructures. Time-integrated and time-resolved photoluminescence (PL) data in combination with numerical calculations allow the identification and assignment of the manifold emission features to three different spatial recombination centers within the NWs. The recombination processes in the QWRs are driven by efficient charge carrier transfer effects between the different optically active regions, providing high intense QWR luminescence despite their small volume. This is deduced by a fast rise time of the QWR PL, which is similar to the fast decay-time of adjacent carrier reservoirs. Such processes, feeding the ultra-narrow QWRs with carriers from the relatively large NWs, can be the key feature towards the realization of future QWR-based devices. While processing of single quantum structures with diameters in the nm range presents a serious obstacle with respect to their integration into electronic or photonic devices, the QWRs presented here can be analyzed and processed using existing techniques developed for single NWs.

The novel automatic flow system, direct-injection detector (DID) integrated with multi-pumping flow system (MPFS), dedicated for the photometric determination of orthophosphates in wastewater and freshwater samples is for the first time described. All reagents and the sample were injected simultaneously, in counter-current into the reaction-detection chamber by the system of specially selected for this purpose solenoid micro-pumps. The micro-pumps provided good precision and accuracy of the injected volumes. For the determination of orthophosphates, the molybdenum blue method was employed. The developed method can be used to detect orthophosphate in the range 0.1-12 mg L -1 , with the repeatability (RSD) about 2.2% at 4 mg L -1 and a very high injection throughput of 120 injections h -1 . It was possible to achieve a very small consumption of reagents (10 μL of ammonium molybdate and 10 μL of ascorbic acid) and sample (20 μL). The volume of generated waste was only 440 μL per analysis. The method has been successfully applied, giving a good accuracy, to determination of orthophosphates in complex matrix samples: treated wastewater, lake water and reference sample of groundwater. The developed system is compact, small in both size and weight, requires 12 V in supply voltage, which are desirable for truly portable equipment used in routine analysis. The simplicity of the system should result in its greater long-time reliability comparing to other flow methods previously described.

Exploring the limits of spontaneous emission coupling is not only one of the central goals in the development of nanolasers, it is also highly relevant regarding future large-scale photonic integration requiring energy-efficient coherent light sources with a small footprint. Recent studies in this field have triggered a vivid debate on how to prove and interpret lasing in the high-β regime. We investigate close-to-ideal spontaneous emission coupling in GaN nanobeam lasers grown on silicon. Such nanobeam cavities allow for efficient funneling of spontaneous emission from the quantum well gain material into the laser mode. By performing a comprehensive optical and quantum-optical characterization, supported by microscopic modeling of the nanolasers, we identify high-β lasing at room temperature and show a lasing transition in the absence of a threshold nonlinearity at 156 K. This peculiar characteristic is explained in terms of a temperature and excitation power-dependent interplay between zero-dimensional and two-dimensional gain contributions.

Aim: Although chronic pain is common in older adults, its treatment is frequently inappropriate. This problem is particularly prevalent in nursing home residents. We therefore developed an intervention to optimize pain management and evaluated its effects on pain intensity and pain interference with function in nursing home residents in Germany., Methods: In a cluster-randomized controlled intervention, 195 residents of 12 Berlin nursing homes who were affected by pain were surveyed at three points of measurement. A modified German version of the Brief Pain Inventory was used to assess pain sites, pain intensity and pain interference with function in various domains of life. The intervention consisted of separate training measures for nursing staff and treating physicians., Results: The primary objective of reducing the mean pain intensity by 2 points was not achieved, partly because the mean pain intensity at baseline was relatively low. However, marginal reductions in pain were observed in the longitudinal assessment at 6-month follow up. The intervention and control groups differed significantly in the intensity sum score and in the domain of walking. Furthermore, the proportion of respondents with pain scores >0 on three pain intensity items decreased significantly., Conclusions: Given the multifocal nature of the pain experienced by nursing home residents, improving the pain situation of this vulnerable group is a major challenge. To achieve meaningful effects not only in pain intensity, but especially in pain interference with function, training measures for nursing staff and physicians need to be intensified, and long-term implementation appears necessary. Geriatr Gerontol Int 2017; 17: 1534-1543., (© 2016 Japan Geriatrics Society.)

A novel approach for the automatic chemiluminescence (CL) analysis of the complex samples is proposed. A multi-pumping flow system was successfully combined with fluidized reactor and direct-injection CL detector. The possibility of the approach was demonstrated on the determination of uric acid in saliva samples. Uric acid is clinically important analyte and its determination in biological fluids is related to human organism dysfunctions, such as gout. For the first time, the fast luminol - N-bromosuccinimide (NBS) reaction in an alkaline medium was used for the CL determination of uric acid in saliva samples. The CL intensity is greatly quenched in the presence of the analyte. The method includes on-line separation of uric acid from the saliva samples based on fluidized beds strategy using anion-exchange resin Dowex ® 2×8 followed by the elution and CL determination using a direct-injection CL detector. The stroke pulsations of the solenoid micro-pumps provided the floating of the anion exchange resin in a sample phase and uric acid separation from the sample matrix into a sample pre-treatment block of flow system. To obtain efficient elution of analyte an eluent circulation was applied. Under the optimal conditions, the detector response for uric acid was linear in the logarithmic concentration ranges from 6·10 -6 to 1·10 -3 molL -1 . The limit of detection, calculated from a blank test based on 3σ, was 2·10 -6 molL -1 . Fluidized bed strategy allows us to exclude saliva matrices influence on the luminol-NBS CL reaction, which results in improved selectivity. The applicability of the method developed is demonstrated with the help of real sample analysis. The obtained results are confirmed by reference HPLC-UV method., (Copyright © 2017 Elsevier B.V. All rights reserved.)

Approximately one in every two German nursing home residents falls at least once in a 1-year period and just as many report a fear of falling. It has been hypothesized that falls self-efficacy mediates the relationship between fear of falling and functional ability. The aim of the current study was to develop the German Nursing Home Falls Self-Efficacy Scale, examine its validity, and estimate a cutoff point to differentiate nursing home residents with low or high falls self-efficacy. Nursing home residents were assessed at baseline (n = 178, mean age = 83.7 years) and 6-month follow up (n = 115, mean age = 83.9 years). Factorial and construct validity analyses provided preliminary support for the validity of the scale. A cutoff point of 11.5 was generated by receiver operating characteristic curve analysis. This scale may assist health care professionals in differentiating between nursing home residents with low and high falls self-efficacy and supporting residents in providing appropriate interventions. [Res Gerontol Nurs. 2016; 9(3):134-144.]., (Copyright 2016, SLACK Incorporated.)

In this work, we present a novel chemiluminescence (CL) method based on direct-injection detector (DID) integrated with the multi-pumping flow system (MPFS) to chemiluminescence determination of the total polyphenol index. In this flow system, the sample and the reagents are injected directly into the cone-shaped detection cell placed in front of the photomultiplier window. Such construction of the detection chamber allows for fast measurement of the CL signal in stopped-flow conditions immediately after mixing the reagents. The proposed DID-CL-MPFS method is based on the chemiluminescence of nanocolloidal manganese(IV)-hexametaphosphate-ethanol system. The application of ethanol as a sensitizer, eliminated the use of carcinogenic formaldehyde. Under the optimized experimental conditions, the chemiluminescence intensities are proportional to the concentration of gallic acid in the range from 5 to 350 ng mL(-1). The DID-CL-MPFS method offers a number of advantages, including low limit of detection (0.80 ng mL(-1)), high precision (RSD = 3.3%) and high sample throughput (144 samples h(-1)) as well as low consumption of reagents, energy and low waste generation. The proposed method has been successfully applied to determine the total polyphenol index (expressed as gallic acid equivalent) in a variety of plant-derived food samples (wine, tea, coffee, fruit and vegetable juices, herbs, spices)., (Copyright © 2016 Elsevier B.V. All rights reserved.)

Unlabelled: The Brief Pain Inventory (BPI) has been psychometrically evaluated worldwide in adult patients with cancer-related and chronic pain in several languages, but never in nursing home residents with chronic pain. To address this gap, we evaluated the validity of a modified version of the BPI, the BPI for nursing home residents (BPI-NHR) in individuals who resided in German nursing homes. One analytic sample included 137 nursing home residents (mean age, 83.3 years; SD, 8.0 years) without any missing values. An extended sample also included individuals with previous missing values that were substituted with the personal mean (n = 163; mean age, 83.3 years; SD, 8.3 years). Principal axis factoring with oblimin rotation was used to compute the final 2-factor solution for the substituted sample. These factors explained 71.7% of the variance. Internal consistency was calculated using Cronbach α, and showed excellent results. Concurrent validity was tested using nonparametric correlation analyses of the BPI-NHR with the pain medication scale. The present findings support the reliability and validity of the BPI-NHR for very old nursing home residents. Further evaluation of this measure is needed to examine face validity and the effect of multimorbidity on pain interference with function., Perspective: In this article we present psychometric properties of the BPI originally developed to assess cancer pain, extended to measure chronic nonmalignant pain in younger and middle-aged patients, and now further developed to measure pain intensity and interference with function among very old nursing home residents. Thus, the BPI-NHR might assist clinicians and researchers interested in assessment of pain intensity and interference in elderly individuals who reside in nursing homes., (Copyright © 2016 American Pain Society. Published by Elsevier Inc. All rights reserved.)

The structure of sludge is closely associated with the process of wastewater treatment. Synthetic dyestuff wastewater and sewage were coagulated using the PAX and PIX methods, and electro-coagulated on aluminium electrodes. The processes of wastewater treatment were supported with an organic polymer. The images of surface structures of the investigated sludge were obtained using scanning electron microscopy (SEM). The software image analysis permitted obtaining plots log A vs. log P, wherein A is the surface area and P is the perimeter of the object, for individual objects comprised in the structure of the sludge. The resulting database confirmed the 'self-similarity' of the structural objects in the studied groups of sludge, which enabled calculating their fractal dimension and proposing models for these objects. A quantitative description of the sludge aggregates permitted proposing a mechanism of the processes responsible for their formation. In the paper, also, the impact of the structure of the investigated sludge on the process of sedimentation, and dehydration of the thickened sludge after sedimentation, was discussed.

Background: To evaluate the effect of interventions for general practitioners and nursing home staff to improve pain severity and appropriateness of pain medication in nursing home residents (NHR)., Methods: This cluster-randomized controlled trial was conducted in six nursing homes in the intervention and control group, respectively. Pain management was analysed before (T0) and after (T1, T2) an educational intervention in 239 NHR, aged ≥65 years, without moderate or severe cognitive impairment. Primary and secondary outcomes were average pain severity and appropriateness of pain medication as determined with the Numeric Rating Scale and Pain Medication Appropriateness Scale (PMASD ), respectively., Results: At T0, 72.2% and 73.7% of NHR (mean age 83 years) reported pain (average pain severity 2.4) in the intervention and control group, respectively. The PMASD at T0 was 53.9 in the intervention group and 60.8 in the control group (p = 0.12), while 20.6% compared to 6.9% (p = 0.009) received no pain medication in the two groups. At T2, non-significant improvements in the average pain severity (1.59) and PMASD (61.07) were observed in the intervention group. Moreover, the mean individual PMASD increased by 8.09 (p = 0.03) and the proportion of NHR without pain medication decreased by 50% (p = 0.03) in the intervention group. No appreciable changes were found in the control group at T2., Conclusions: NHR exhibited a high prevalence of pain with overall low severity, while a high proportion of individuals received inappropriate pain medications. Both findings were not significantly improved by the intervention, although some aspects of drug treatment were meaningful improved., (© 2015 European Pain Federation - EFIC®)

The reported prevalence of pain among nursing home residents (NHRs) is high. Insufficient use of analgesics, the conventional pain management strategy, is often reported. Whether and to what extent nonpharmacologic therapies (NPTs) are used to manage the pain of NHRs in Germany is largely unknown. The aim of this cluster-randomized trial was to assess the NPTs provided and to enhance the application and prescription of NPTs in NHRs on an individual level. There were six nursing homes in the intervention group and six in the control group. There were 239 NHRs, aged ≥65 years, with an average Mini-Mental State Examination score of at least 18 at baseline. Pain management interventions (cluster level) included an online course for physicians and 1-day seminar for nurses. Data on NPT applied by nurses and therapeutic NPT prescribed by physicians were obtained from residents' nursing documentation. Face-to-face interviews with NHRs assessed the NPT received. At baseline, 82.6% of NHR (mean age 83 years) were affected by pain, but less than 1 in 10 received NPT. The intervention did not result in a significant increase in the NPT applied by nurses, but did significantly increase the therapeutic NPT prescribed by physicians. Residents were active in using NPT to self-manage their pain. Given the prevalence of pain in NHRs, there is a clear need to improve pain management in this population. Extended use of NPT offers a promising approach. We recommend that nurses provide residents with education on pain-management techniques to support them in taking a proactive role in managing their pain., (Copyright © 2015 American Society for Pain Management Nursing. Published by Elsevier Inc. All rights reserved.)

Hybridization between genetically distinct taxa is a complex evolutionary process. One challenge to studying hybrid populations is quantifying the degree to which non-native genes have become evenly mixed among individuals in the population. In this paper, we present a variance-based parameter, md, that measures the degree to which non-native genes are evenly distributed among individuals in a population. The parameter has a minimum value of 0 for populations in which individuals from multiple taxa are present but have not interbred, and a maximum value of 1 for populations in which all individuals have the same amount of non-native ancestry. A recurrence equation showed that relatively few generations of random mating are required for md to approach 1 (indicating a well-mixed population), and that md is independent of initial amounts of non-native ancestry. The parameter is mathematically equivalent to FST and we show how existing formulae for FST can be used to estimate md when diagnostic loci are available. Computer simulations showed this estimator to have very little bias for realistic amounts of data.

We present a novel chemiluminescence detector, with a cone-shaped detection chamber where the analytical reaction takes place. The sample and appropriate reagents are injected directly into the chamber in countercurrent using solenoid-operated pulse micro-pumps. The proposed detector allows for fast measurement of the chemiluminescence signal in stop-flow conditions from the moment of reagents mixing. To evaluate potential applications of the detector the Fenton-like reaction with a luminol-H2O2 system and several transition metal ions (Co(2+), Cu(2+), Cr(3+), Fe(3+)) as a catalyst were investigated. The results demonstrate suitability of the proposed detector for quantitative analysis and for investigations of reaction kinetics, particularly rapid reactions. A multi-pumping flow system was designed and optimized. The developed methodology demonstrated that the shape of the analytical signals strongly depends on the type and concentration of the metal ions. The application of the detector in quantitative analysis was assessed for determination of Fe(III). The direct-injection chemiluminescence detector allows for a sensitive and repeatable (R.S.D. 2%) determination. The intensity of chemiluminescence increased linearly in the range from about 0.5 to 10 mg L(-1) Fe(III) with the detection limit of 0.025 mg L(-1). The time of analysis depended mainly on reaction kinetics. It is possible to achieve the high sampling rate of 144 samples per hour., (Copyright © 2014 Elsevier B.V. All rights reserved.)

Background: Non-response bias is a major problem for the validity of survey answers. Analyses of reasons for non-response in surveys with nursing home residents (NHR) are scarce., Aim and Method: The aim of this study was to develop reliable and valid categories which represent reasons for non-response in nursing homes using the "Prozessmodell induktiver Kategorienbildung" following Mayring (2010). Furthermore, characteristics of unit non-responder and responder were compared., Results: Forming of categories of reasons for non-response was conducted with 522 NHR, longitudinally. Four major categories were identified (general refusal, health reasons, accessibility, excessive demand) and further 17 subcategories. Unit-non-responder and responder did not differ in age and sex; however follow-up non-responder showed differences in marital status, training qualification, and cognitive status., Conclusions: The presented scheme of categories can be used to assess reasons for non-response in nursing homes. Standardised assessment of reasons for non-response may contribute to higher response rates in this setting.

Although semiconductor excitons consist of a fermionic subsystem (electron and hole), they carry an integer net spin similar to Cooper-electron-pairs. While the latter cause superconductivity by forming a Bose-Einstein-condensate, excitonic condensation is impeded by, for example, a fast radiative decay of the electron-hole pairs. Here, we investigate the behaviour of two electron-hole pairs in a quantum dot with wurtzite crystal structure evoking a charge carrier separation on the basis of large spontaneous and piezoelectric polarizations, thus reducing carrier overlap and consequently decay probabilities. As a direct consequence, we find a hybrid-biexciton complex with a water molecule-like charge distribution enabling anomalous spin configurations. In contrast to the conventional-biexciton complex with a net spin of s=0, the hybrid-biexciton exhibits s=±3, leading to completely different photoluminescence signatures in addition to drastically enhanced charge carrier-binding energies. Consequently, the biexcitonic cascade via the dark exciton can be enhanced on the rise of temperature as approved by photon cross-correlation measurements.

Background: The pain medication appropriateness scale (PMASD) was developed in 2006 in the USA to evaluate the quality and appropriateness of pain treatment in nursing home residents (NHR). This tool can be used to identify potential problems with the pharmacological treatment of pain., Methods: We developed a German version (PMASD) adapted to the German setting and applied it in Germany to NHR with and without cognitive impairment for the first time. In agreement with the original instrument a test result of >67 % was considered as appropriate pain treatment., Results: For the 560 analyzed NHR the average SPMAS score was 39±1,7 (range from -67 to +100). Overall 72% of the study population did not achieve the defined threshold for appropriate pain management., Conclusions: An appropriate tool for quantitative evaluation of pain treatment was so far not available in Germany. The PMASD analysis showed deficits of pain management in NHR. This tool showed good practicability in Germany and could provide a valuable tool for pain treatment in clinical research and practice.

Recognizing the ageing of populations and expected increase in prevalence of dementia, the necessity of research involving persons with dementia is widely agreed upon. Autonomy is key to nursing home residents' well-being and quality of life, but this phenomenon has not been thoroughly assessed from the residents' perspective. The aim of this cross-sectional study was to investigate perceived autonomy of nursing home residents. Data on 560 randomly selected residents in 40 nursing homes in two German federal states were generated by face-to-face interviews, psychological and physical assessments, analysis of nursing records, and acquisition of institutional parameters. This paper reports on a subsample (n = 179) that met screening requirements, including subjects with and without mild cognitive impairment (Mini Mental Status Examination score 30-18), who completed the Hertz Perceived Enactment of Autonomy Scale (HPEAS). The mean score of HPEAS was 101.1 ± 14.5 (range 54-122). In our population, Cronbach's alpha was 0.89. Scores in HPEAS were not related to demographical factors but positively associated with increasing self-efficacy and absence of pain. The novel findings contribute to an understanding of autonomy from the residents' perspective., (© 2012 Wiley Publishing Asia Pty Ltd.)

The automated techniques of measurement of water parameters are developed based on flow analysis (flow injection analysis, sequential injection analysis). PEDD detectors (paired emitter-detector diode), built with the use of two paired light-emitting diodes (LEDs) - emission and detection, can serve that purpose. The aim of the studies was to optimize the system for determination of the dissolved organic substances in coloured water with the use of PEDDs in the flowing-stream measurement system. The investigations were conducted for a number of concentrations of the humic, fulvic and tannic acids, which were measured as the dissolved organic carbon (DOC). Three arrangements of diodes (PEDD) with a selected emission spectrum and absorption characteristics were used. A two-beam flow cell was designed for the measurements. The signal from the detection diode was recorded and converted into absorbance through software written for that purpose. The results obtained showed a high sensitivity in relation to the concentration as well as the selectivity in the type of substances studied. A miniature and cheap photometric flow analysis set was proposed, adapted to work with one or several light wavelengths and steered by a microprocessor unit.

MODOMICS is a database of RNA modifications that provides comprehensive information concerning the chemical structures of modified ribonucleosides, their biosynthetic pathways, RNA-modifying enzymes and location of modified residues in RNA sequences. In the current database version, accessible at http://modomics.genesilico.pl, we included new features: a census of human and yeast snoRNAs involved in RNA-guided RNA modification, a new section covering the 5'-end capping process, and a catalogue of 'building blocks' for chemical synthesis of a large variety of modified nucleosides. The MODOMICS collections of RNA modifications, RNA-modifying enzymes and modified RNAs have been also updated. A number of newly identified modified ribonucleosides and more than one hundred functionally and structurally characterized proteins from various organisms have been added. In the RNA sequences section, snRNAs and snoRNAs with experimentally mapped modified nucleosides have been added and the current collection of rRNA and tRNA sequences has been substantially enlarged. To facilitate literature searches, each record in MODOMICS has been cross-referenced to other databases and to selected key publications. New options for database searching and querying have been implemented, including a BLAST search of protein sequences and a PARALIGN search of the collected nucleic acid sequences.

Pain and fear of falling (FOF) are modifiable factors that might play an important role in functional performance of nursing homes residents (NHR). Both factors are characterised by deficits in research and provision of long-term care services. The purpose of this study was to examine the functional performance of NHR with and without pain or FOF. Quantitative data were collected on NHR in Berlin and Brandenburg using a cross-sectional design. The cognitive status was assessed using the Minimental state test. Existing pain and FOF were assessed as a question part of interview. Functional performance was examined using the Barthel Index (BI) the Timed «up & go»-Test. Multiple linear regression analyses were performed to investigate the research question and the influence of additional explanatory variables (age, sex, relevant somatic morbidity). 217 NHR without considerable cognitive impairment (MMST >= 20) participated. 65 % of the NHR suffered from pain and 48 % had FOF. There was a statistically significant association between Pain or FOF und lower functional mobility. With respect to NHR able to walk, there was statistically significant association between Pain or FOF und lower performance in activities of daily living. Possibilities for interventions which might have positive effects on functional performance of NHR are an improved pain treatment and interventions to reduce FOF.

Purpose: To explore different institutional barriers to and facilitators of physical activity (PA) in nursing homes., Methods: Cross-sectional survey of 40 German nursing homes and 217 nursing-home residents (NHRs; M ± SD age 80 ± 10.2 yr, 55% women, MMSE ≥20). Quantitative data were collected on the structural characteristics of nursing homes and the PA services available., Results: Forms of exercise available were not adequately communicated to residents. Overall participation was below 50%. Awareness was significantly higher in residents with informed relatives (p = .003). A broad range of forms of exercise was generally available (M ± SD 5 ± 2.22, range 0-10), but they were rarely tailored to NHRs' needs and their effectiveness remains questionable., Conclusion: Multidimensional opportunities to promote PA in NHRs are identified.

A novel direct-injection detector (DID) integrated with multi-pumping flow system (MPFS) for the photometric determination of iron is proposed. Paired emitter-detector diodes have been used as a photometric detection system. The sample and reagent were injected using appropriate solenoid pulse micro-pumps directly into the detection chamber where effective mixing occured. The use of proposed stop-flow detector considerably simplified the analytical procedure. The potassium thiocyanate has been chosen as a chromogenic reagent for photometric Fe(III) detection. The total volume of reagent and sample/standard solutions involved in the detection process was adjusted to the volume of the reaction-detection chamber. Calibration graph was found to be linear in the range up to 10mgL(-1). The detection limit (3s(b)/S) was 0.15mgL(-1). The repeatability (R.S.D.), calculated from 10 analyses of sample containing 5mgL(-1) Fe(III), was 1.5% and the sample throughput 180 determinations per hour. The consumption of sample and reagent was 20μL each with the waste generation at the level of 0.24mL. The applicability of the proposed method to the determination of total iron in groundwater samples has been proved. The analytical parameters are compared to those obtained exploiting the MPFS system with typical configuration containing a confluence point and reaction coil., (Copyright © 2012 Elsevier B.V. All rights reserved.)

Introduction: The aim of this study was to investigate the frequency of benzodiazepines, antidementia and antipsychotic drug prescriptions in nursing home residents (NHR).Data of a German health insurance company were retrospectively analyzed for the year 2008., Methods: The study cohort comprised 13,042 NHR (82% women, mean age 83.6 ± 7 years). Following analgetics, antipsychotic drugs were the second most frequently prescribed drug group with 13.3% of all prescriptions. Dementia was diagnosed in 8 017 (61.5%) NHR. Thereof 51.6% received an antipsychotic, 17.3% a benzodiazepine and 15.2% an antidementia pharmaceutical, respectively. 18.1% of NHR with dementia and antipsychotic drug prescriptions were in combined treatment with antidementia pharmaceuticals. The rate of antipsychotic drug prescribing was significantly doubled in NHR with dementia compared to those without this diagnosis (p<0.01); the most frequently prescribed antipsychotics were melperone, risperidone and pipamperone., Discussion: This study demonstrates the wide-spread use of psychotropic drugs in NHR. Moreover, dementia in NHR was associated with antipsychotic drug prescribing in every second patient. This highlights the need for further studies analyzing alternative treatments for dementia-related symptoms., (© Georg Thieme Verlag KG Stuttgart · New York.)

Background: Current knowledge about the quality and appropriateness of pharmacological pain treatment in nursing home residents (NHR), particularly in NHR with moderate to severe cognitive impairment, is poor., Methods: This observational cross-sectional study assessed pain treatment in a random sample of NHR with or without cognitive impairment from nursing homes in Germany. Prescribed drugs, pain intensity and frequency, diagnoses, and surgical procedures and injuries during the last 4 weeks were documented. Quality and appropriateness of pain medication were assessed by analysis of pain medications and the Pain Medication Appropriateness Scale (PMAS) score (S(PMAS) ), with a cut-off value of >67% indicating appropriate pain treatment., Results: A total of 321 residents (62% women) were studied, including 152 (47%) with severe cognitive impairment. The most frequently prescribed analgesics were dipyrone, fentanyl, tramadol and ibuprofen. The mean S(PMAS) was 48.5 ± 1.5 (range, -33 to +100). Residents with prescribed scheduled analgesics had a significantly better S(PMAS) than patients without such treatment (S(PMAS) 58 ± 1.5 vs. 37 ± 2.5, p < 0.01). NHR without current pain had significantly better S(PMAS) than residents suffering from pain (S(PMAS) 47 ± 1.9 vs. 59 ± 4.2, p = 0.01). With an S(PMAS) of 69 ± 1.5, residents (n = 106) with scheduled pain medication plus PRN analgesics achieved the highest scores in the population. Overall, similar results were found in NHR with and in NHR without cognitive impairment., Conclusion: Our study points to a significant deficit in pain treatment in German NHR, including NHR with or without cognitive impairment., (© 2011 European Federation of International Association for the Study of Pain Chapters.)

Previous research has suggested that adding active learning to traditional college science lectures substantially improves student learning. However, this research predominantly studied courses taught by science education researchers, who are likely to have exceptional teaching expertise. The present study investigated introductory biology courses randomly selected from a list of prominent colleges and universities to include instructors representing a broader population. We examined the relationship between active learning and student learning in the subject area of natural selection. We found no association between student learning gains and the use of active-learning instruction. Although active learning has the potential to substantially improve student learning, this research suggests that active learning, as used by typical college biology instructors, is not associated with greater learning gains. We contend that most instructors lack the rich and nuanced understanding of teaching and learning that science education researchers have developed. Therefore, active learning as designed and implemented by typical college biology instructors may superficially resemble active learning used by education researchers, but lacks the constructivist elements necessary for improving learning.

A novel flow photometric detector based on paired emitter-detector diodes (PEDD), coupled with solenoid pulse micro-pumps is presented. The photometric detection chamber also plays a role of the reaction chamber. Both solutions, a sample and a reagent, are injected by solenoid micro-pumps directly and simultaneously into the chamber in countercurrent. This method ensures fast and effective mixing of the injected solutions. A good accuracy and precision of the injected volumes assure the pulse micro-pumps. This method, in comparison with other flow methods, does not require the application of the reaction coil. Thanks to this, the dispersion of the sample is minimized. The presented flow network is easy to control, miniaturize and exhibits a very low consumption of reagents and the sample. Two chemical systems were chosen and presented as models of photometric reactions: the first - Fe(III) with thiocyanate, and the second - Cr(VI) with 1,5-diphenylcarbazide. To obtain the highest repeatability, the total volume of the solutions should be smaller than the volume of the reaction-detection chamber. In this case, the whole coloured product remains in the chamber. The use of the proposed direct-injection PEDD detector considerably simplifies analytical procedures. The shape of analytical signals and their potential applications have been discussed., (Copyright © 2011 Elsevier B.V. All rights reserved.)

One of the primary goals of population genetics is to succinctly describe genetic relationships among populations, and the computer program STRUCTURE is one of the most frequently used tools for doing so. The mathematical model used by STRUCTURE was designed to sort individuals into Hardy-Weinberg populations, but the program is also frequently used to group individuals from a large number of populations into a small number of clusters that are supposed to represent the main genetic divisions within species. In this study, I used computer simulations to examine how well STRUCTURE accomplishes this latter task. Simulations of populations that had a simple hierarchical history of fragmentation showed that when there were relatively long divergence times within evolutionary lineages, the clusters created by STRUCTURE were frequently not consistent with the evolutionary history of the populations. These difficulties can be attributed to forcing STRUCTURE to place individuals into too few clusters. Simulations also showed that the clusters produced by STRUCTURE can be strongly influenced by variation in sample size. In some circumstances, STRUCTURE simply put all of the individuals from the largest sample in the same cluster. A reanalysis of human population structure suggests that the problems I identified with STRUCTURE in simulations may have obscured relationships among human populations-particularly genetic similarity between Europeans and some African populations.

We describe 12 diagnostic single nucleotide polymorphism (SNP) assays for use in species identification among rainbow and cutthroat trout: five of these loci have alleles unique to rainbow trout (Oncorhynchus mykiss), three unique to westslope cutthroat trout (O. clarkii lewisi) and four unique to Yellowstone cutthroat trout (O. clarkii bouvieri). These diagnostic assays were identified using a total of 489 individuals from 26 populations and five fish hatchery strains., (© 2010 Blackwell Publishing Ltd.)

Autonomy is an exceptionally complex philosophical concept which is present in ethical considerations in health care settings. Currently, no consistent definition of autonomy exists. From the perspective of the authors, self-determination and capacity to act independently are essential aspects of autonomy. While there are limited general results regarding autonomy in old age, autonomy of nursing home residents and the corresponding critical influence factors still lack in-depth examination. The aim of this article is to contribute to a more thorough understanding of autonomy of nursing home residents. Due to the high percentage of residents with cognitive impairment, this population plays a crucial role regarding the conceptualisation of autonomy. Various approaches combined with the perspectives developed by the interdisciplinary PAiN-Project team (Pain and Autonomy in the Nursing Home), led to the formulation of a novel conceptualisation of autonomy. Based on theoretical and discursive considerations, the model "Determination Factors of Autonomy" focuses on the residents' self-determination and ability to perform activities of daily living in the nursing home context. According to the author's conceptualisation, autonomy occurs in various ranges in regard to self-awareness as well as the appreciation of autonomy by others.

Bifurcating evolutionary trees are commonly used to describe genetic relationships between populations, but may not be appropriate for populations that did not evolve in a hierarchical manner. The degree to which bifurcating trees distort genetic relationships between populations can be quantified with R(2), the proportion the variation in a matrix of genetic distances between populations that is explained by a tree. Computer simulations were used to measure how well the unweighted pair group method with arithmetic mean (UPGMA) and neighbor-joining (NJ) trees depicted population structure for three evolutionary models: a hierarchical model of population fragmentation, a linear stepping-stone model of gene flow and a two-dimensional stepping-stone model of gene flow. These simulations showed that the UPGMA did an excellent job of describing population structure when populations had a bifurcating history of fragmentation, but severely distorted genetic relationships for the linear and two-dimensional stepping-stone models. The NJ algorithm worked well in a broader range of evolutionary histories, including the linear stepping-stone model. A computer program for performing the calculations described in this study is available for download at www.montana.edu/kalinowski.

The replica exchange (RE) method is increasingly used to improve sampling in molecular dynamics (MD) simulations of biomolecular systems. Recently, we implemented the united-residue UNRES force field for mesoscopic MD. Initial results from UNRES MD simulations show that we are able to simulate folding events that take place in a microsecond or even a millisecond time scale. To speed up the search further, we applied the multiplexing replica exchange molecular dynamics (MREMD) method. The multiplexed variant (MREMD) of the RE method, developed by Rhee and Pande, differs from the original RE method in that several trajectories are run at a given temperature. Each set of trajectories run at a different temperature constitutes a layer. Exchanges are attempted not only within a single layer but also between layers. The code has been parallelized and scales up to 4000 processors. We present a comparison of canonical MD, REMD, and MREMD simulations of protein folding with the UNRES force-field. We demonstrate that the multiplexed procedure increases the power of replica exchange MD considerably and convergence of the thermodynamic quantities is achieved much faster.

A method was developed for assessing ascorbic acid concentration in commercial fruit juice by cyclic voltammetry. The anodic oxidation peak for ascorbic acid occurs at about 490 mV on a Pt disc working electrode (versus SCE). The influence of the potential sweep speed on the peak height was studied. The obtained calibration graph shows a linear dependence between peak height and ascorbic acid concentration in the domain (0.1-10 mmol.L(-1)). The equation of the calibration graph was y = 6.391x + 0.1903 (where y represents the value of intensity measured for the anodic peak height, expressed as muA and x the analyte concentration, as mmol.L(-1), r(2) = 0.9995, r.s.d. = 1.14%, n = 10, C(ascorbic acid) = 2 mmol.L(-1)). The developed method was applied to ascorbic acid assessment in fruit juice. The ascorbic acid content determined ranged from 0.83 to 1.67 mmol.L(-1) for orange juice, from 0.58 to 1.93 mmol.L(-1) for lemon juice, and from 0.46 to 1.84 mmol.L(-1) for grapefruit juice. Different ascorbic acid concentrations (from standard solutions) were added to the analysed samples, the degree of recovery being comprised between 94.35% and 104%. Ascorbic acid determination results obtained by cyclic voltammetry were compared with those obtained by the volumetric method with dichlorophenol indophenol. The results obtained by the two methods were in good agreement.

We report the modification and parametrization of the united-residue (UNRES) force field for energy-based protein structure prediction and protein folding simulations. We tested the approach on three training proteins separately: 1E0L (beta), 1GAB (alpha), and 1E0G (alpha + beta). Heretofore, the UNRES force field had been designed and parametrized to locate native-like structures of proteins as global minima of their effective potential energy surfaces, which largely neglected the conformational entropy because decoys composed of only lowest-energy conformations were used to optimize the force field. Recently, we developed a mesoscopic dynamics procedure for UNRES and applied it with success to simulate protein folding pathways. However, the force field turned out to be largely biased toward -helical structures in canonical simulations because the conformational entropy had been neglected in the parametrization. We applied the hierarchical optimization method, developed in our earlier work, to optimize the force field; in this method, the conformational space of a training protein is divided into levels, each corresponding to a certain degree of native-likeness. The levels are ordered according to increasing native-likeness; level 0 corresponds to structures with no native-like elements, and the highest level corresponds to the fully native-like structures. The aim of optimization is to achieve the order of the free energies of levels, decreasing as their native-likeness increases. The procedure is iterative, and decoys of the training protein(s) generated with the energy function parameters of the preceding iteration are used to optimize the force field in a current iteration. We applied the multiplexing replica-exchange molecular dynamics (MREMD) method, recently implemented in UNRES, to generate decoys; with this modification, conformational entropy is taken into account. Moreover, we optimized the free-energy gaps between levels at temperatures corresponding to a predominance of folded or unfolded structures, as well as to structures at the putative folding-transition temperature, changing the sign of the gaps at the transition temperature. This enabled us to obtain force fields characterized by a single peak in the heat capacity at the transition temperature. Furthermore, we introduced temperature dependence to the UNRES force field; this is consistent with the fact that it is a free-energy and not a potential energy function. beta

Chronopotentiometry on planar lipid bilayer (BLM) is proposed as a method for modeling the electrical phenomena in electroporated cell. Two techniques are discussed: constant-current and linear-current chronopotentiometry. It is proposed that the constant-current chronopotentiometry may provide basis for modeling the electroporated cell shortly after the removal of the electric field, when activity of cellular pumps counteracts ionic fluxes through the electropore and ionic channels. The linear-current method can be considered for modeling the cell in the later stage after electroporation, when energetical resources of the cell are gradually getting exhausted and the activity of pumps decreases. Based on this idea, it may be postulated that the electropore in the cell has fluctuating dynamics whose stochastic characteristics, similarly as biological channels, shows 1/f noise. The model implies that the fluctuations would disappear leaving the electropore with a constant resistance when efficiency of the pumps becomes very small. The results of chronopotentiometry also may suggest that opening time, conductivity and selectivity of the electropore can be controlled by the cell environment or membrane composition.

Experiments show significant effects of an electric field on lipid membrane, leading to a pore formation when a high intensity field is applied. The phenomenon of electroporation is preceded by the induction and expansion of defects, responsible for the pre-pore excitation. We examine the mechanism of the induction of the field-driven defects by Monte Carlo simulations. The study is based on the improved Pink's model, which includes explicit interactions between the polar heads and energy of interactions between the heads and the field. No anomalous deformation of the molecules is considered. The study, provided for bilayer dipalmitoyl-phosphatidylcholine (DPPC) membrane in the gel (300 K) and fluid (330 K) phases, shows dependence of the membrane conformational and energetical state on the value of the electric field. We observe that the electric field affects the number of molecules in the gel and in the fluid states. In the layer at the negative potential, when the transmembrane voltage is above U(c) approximately 280 mV, lipid heads abruptly reorient and the number of local spots with fluid conformation increases. The other layer slightly tends to tighten its structure, producing additional mechanical stress between layers. Lipids showed complete insensitivity to the electric field within physiological limits, U<70 mV.

Relatedness is often estimated from microsatellite genotypes that include null alleles. When null alleles are present, observed genotypes represent one of several possible true genotypes. If null alleles are detected, but analyses do not adjust for their presence (ie, observed genotypes are treated as true genotypes), then estimates of relatedness and relationship can be incorrect. The number of loci available in many wildlife studies is limited, and loci with null alleles are commonly a large proportion of data that cannot be discarded without substantial loss of power. To resolve this problem, we present a new approach for estimating relatedness and relationships from data sets that include null alleles. Once it is recognized that the probability of the observed genotypes is dependent on the probabilities of a limited number of possible true genotypes, the required adjustments are straightforward. The concept can be applied to any existing estimators of relatedness and relationships. We review established maximum likelihood estimators and apply the correction in that setting. In an application of the corrected method to data from striped hyenas, we demonstrate that correcting for the presence of null alleles affect results substantially. Finally, we use simulated data to confirm that this method works better than two common approaches, namely ignoring the presence of null alleles or discarding affected loci.

The coefficient of variation of estimates of three genetic distances (standard genetic distance of Nei, chord distance, FST) was examined with computer simulation to determine if large samples (per population) are necessary to precisely estimate genetic distances at loci with high levels of polymorphism. These simulations showed that loci with high mutation rates produce estimates of genetic distance with lower coefficients of variation than loci with lower mutation rates--without requiring larger sample sizes from each population. In addition, the rate at which increasing sample sizes decreases the coefficient of variation of estimates of genetic distances was shown to be approximately determined by the value of FST between the populations being sampled. When FST was greater than 0.05, sampling fewer than 20 individuals (per population) should be sufficient. When FST was less than 0.01, sampling 100 individuals (per population) or more will be useful.

This paper presents the results of constant-current (chronopotentiometric) measurements of the egg yolk phosphatidylcholine (PC) bilayer membrane without and with cholesterol. The experiments were performed on planar bilayer lipid membrane (BLM) formed by the Mueller-Rudin method. It is demonstrated that the constant-intensity current flow through bilayer membranes generated fluctuating pores in their structure. The presence of cholesterol in the membrane caused an increase in the value of the breakdown potential. It is postulated that greater stability of the bilayer with cholesterol can result from an increased critical pore radius (at which the bilayer would undergo irreversible rupture). This confirms that cholesterol has a stabilizing effect on BLM. Besides, our results suggest that addition of cholesterol causes shift in the distribution of pore conductance towards a smaller value. It is suggested that this can be connected with the phenomenon of domain formation in the membranes containing high concentration of cholesterol. Moreover, it is shown that chronopotentiometry with programmable current intensity is a promising method for observation of the membrane recovery process.

Stochastic properties of a fluctuating nanopore generated and sustained by an electric field in a lipid bilayer membrane are studied. It is shown that the process of voltage fluctuations, in the current clamp experiment, is a stochastic fractal with long memory, which is the main reason for its nonstationarity. The aging process contributes to the nonstationarity if molecular interactions in the membrane are weak. An attempt to classify the process reveals a non-Gaussian distribution with long tails, which contradicts the hypothesis of fractional Brownian motion, showing that stable motion may be possible. The self-similarity index, estimated by three different methods, depends on current value and membrane sensitivity to electric field in a well defined and explicable manner. The stochastic analysis provided for calculated conductance of nanopore revealed the process close to 1/f noise, the result observed only for the pores not exceeding 1 nm in diameter, induced in membranes with strong molecular interactions. Our results show that such a pore is the simplest biological system needed for flicker noise to occur, and the complexity of highly regulated protein channel is not a necessary factor. A case of noise 1/f(2), observed for a pore with impeded dynamics, suggests a process without memory in such a situation. A physical interpretation is presented for some of the results.