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Sample records for biological factors determining

  1. Physical and biological factors determining the effective proton range

    Energy Technology Data Exchange (ETDEWEB)

    Grün, Rebecca [Department of Biophysics, GSI Helmholtzzentrum für Schwerionenforschung, Darmstadt 64291 (Germany); Institute of Medical Physics and Radiation Protection, University of Applied Sciences Gießen, Gießen 35390 (Germany); Medical Faculty of Philipps-University Marburg, Marburg 35032 (Germany); Friedrich, Thomas; Krämer, Michael; Scholz, Michael [Department of Biophysics, GSI Helmholtzzentrum für Schwerionenforschung, Darmstadt 64291 (Germany); Zink, Klemens [Institute of Medical Physics and Radiation Protection, University of Applied Sciences Gießen, Gießen 35390, Germany and Department of Radiotherapy and Radiation Oncology, University Medical Center Giessen and Marburg, Marburg 35043 (Germany); Durante, Marco [Department of Biophysics, GSI Helmholtzzentrum für Schwerionenforschung, Darmstadt 64291, Germany and Department of Condensed Matter Physics, Darmstadt University of Technology, Darmstadt 64289 (Germany); Engenhart-Cabillic, Rita [Medical Faculty of Philipps-University Marburg, Marburg 35032, Germany and Department of Radiotherapy and Radiation Oncology, University Medical Center Giessen and Marburg, Marburg 35043 (Germany)

    2013-11-15

    Purpose: Proton radiotherapy is rapidly becoming a standard treatment option for cancer. However, even though experimental data show an increase of the relative biological effectiveness (RBE) with depth, particularly at the distal end of the treatment field, a generic RBE of 1.1 is currently used in proton radiotherapy. This discrepancy might affect the effective penetration depth of the proton beam and thus the dose to the surrounding tissue and organs at risk. The purpose of this study was thus to analyze the impact of a tissue and dose dependent RBE of protons on the effective range of the proton beam in comparison to the range based on a generic RBE of 1.1.Methods: Factors influencing the biologically effective proton range were systematically analyzed by means of treatment planning studies using the Local Effect Model (LEM IV) and the treatment planning software TRiP98. Special emphasis was put on the comparison of passive and active range modulation techniques.Results: Beam energy, tissue type, and dose level significantly affected the biological extension of the treatment field at the distal edge. Up to 4 mm increased penetration depth as compared to the depth based on a constant RBE of 1.1. The extension of the biologically effective range strongly depends on the initial proton energy used for the most distal layer of the field and correlates with the width of the distal penumbra. Thus, the range extension, in general, was more pronounced for passive as compared to active range modulation systems, whereas the maximum RBE was higher for active systems.Conclusions: The analysis showed that the physical characteristics of the proton beam in terms of the width of the distal penumbra have a great impact on the RBE gradient and thus also the biologically effective penetration depth of the beam.

  2. Adult Learning Open University Determinants study (ALOUD): Biological lifestyle factors associated with study success

    NARCIS (Netherlands)

    Gijselaers, Jérôme; De Groot, Renate; Kirschner, Paul A.

    2012-01-01

    Gijselaers, H. J. M., De Groot, R. H. M., & Kirschner, P. A. (2012, 7 November). Adult Learning Open University Determinants study (ALOUD): Biological lifestyle factors associated with study success. Poster presentation at the International ICO Fall School, Girona, Spain.

  3. Biophysical and biological factors determining the ability to achieve long-term cryobiological preservation

    Energy Technology Data Exchange (ETDEWEB)

    Mazur, P. [Oak Ridge National Lab., TN (United States). Life Sciences Div.

    1997-12-01

    The BESTCapsule will maintain appropriate biological specimens for decades or centuries at cryogenic temperatures in the living state. Maintenance at temperatures below {approximately} {minus}140 C is not a problem. No ordinary chemical reactions in aqueous solutions can occur. The only source of damage will be the slow accumulation of physical damage to DNA from background ionizing radiation. But this source of damage should not become serious in less than a millennium. Rather, the main problem in cryopreservation is to devise procedures for cooling the biological specimens to {minus}196 C and returning them to normal temperatures without inflicting lethal injury. Regardless of the cell type, there are certain encompassing biophysical factors and constraints that determine whether they will survive or die during freezing and thawing. Superimposed on these may be special biological factors that apply to specific cell types. This paper will emphasize the former and give illustrative examples of the latter.

  4. Mixing regime as a key factor to determine DON formation in drinking water biological treatment.

    Science.gov (United States)

    Lu, Changqing; Li, Shuai; Gong, Song; Yuan, Shoujun; Yu, Xin

    2015-11-01

    Dissolved organic nitrogen (DON) can act as precursor of nitrogenous disinfection by-products formed during chlorination disinfection. The performances of biological fluidized bed (continuous stirred tank reactor, CSTR) and bio-ceramic filters (plug flow reactor, PFR) were compared in this study to investigate the influence of mixing regime on DON formation in drinking water treatment. In the shared influent, DON ranged from 0.71mgL(-1) to 1.20mgL(-1). The two biological fluidized bed reactors, named BFB1 (mechanical stirring) and BFB2 (air agitation), contained 0.12 and 0.19mgL(-1) DON in their effluents, respectively. Meanwhile, the bio-ceramic reactors, labeled as BCF1 (no aeration) and BCF2 (with aeration), had 1.02 and 0.81mgL(-1) DON in their effluents, respectively. Comparative results showed that the CSTR mixing regime significantly reduced DON formation. This particular reduction was further investigated in this study. The viable/total microbial biomass was determined with propidium monoazide quantitative polymerase chain reaction (PMA-qPCR) and qPCR, respectively. The results of the investigation demonstrated that the microbes in BFB2 had higher viability than those in BCF2. The viable bacteria decreased more sharply than the total bacteria along the media depth in BCF2, and DON in BCF2 accumulated in the deeper media. These phenomena suggested that mixing regime determined DON formation by influencing the distribution of viable, total biomass, and ratio of viable biomass to total biomass. PMID:25585870

  5. Efficient, sparse biological network determination

    Directory of Open Access Journals (Sweden)

    Papachristodoulou Antonis

    2009-02-01

    Full Text Available Abstract Background Determining the interaction topology of biological systems is a topic that currently attracts significant research interest. Typical models for such systems take the form of differential equations that involve polynomial and rational functions. Such nonlinear models make the problem of determining the connectivity of biochemical networks from time-series experimental data much harder. The use of linear dynamics and linearization techniques that have been proposed in the past can circumvent this, but the general problem of developing efficient algorithms for models that provide more accurate system descriptions remains open. Results We present a network determination algorithm that can treat model descriptions with polynomial and rational functions and which does not make use of linearization. For this purpose, we make use of the observation that biochemical networks are in general 'sparse' and minimize the 1-norm of the decision variables (sum of weighted network connections while constraints keep the error between data and the network dynamics small. The emphasis of our methodology is on determining the interconnection topology rather than the specific reaction constants and it takes into account the necessary properties that a chemical reaction network should have – something that techniques based on linearization can not. The problem can be formulated as a Linear Program, a convex optimization problem, for which efficient algorithms are available that can treat large data sets efficiently and uncertainties in data or model parameters. Conclusion The presented methodology is able to predict with accuracy and efficiency the connectivity structure of a chemical reaction network with mass action kinetics and of a gene regulatory network from simulation data even if the dynamics of these systems are non-polynomial (rational and uncertainties in the data are taken into account. It also produces a network structure that can

  6. [Sodium determination in biological fluids].

    Science.gov (United States)

    Cristol, J-P; Balint, B; Canaud, B; Daurés, M-F

    2007-09-01

    Electrolyte disorders are frequently observed in nephrology and intensive care unit department and Na determination is routinely performed in biochemistry laboratories. Three methods are currently available. Flame photometry remains the reference method. With this method the serum sample is diluted before the actual measurement is obtained. Results are expressed as molarity (per Liter of plasma). Potentiometric methods have an increasing importance due to the advances in ion sensitive (selective) electrodes (ISE). Whereas the instruments for routine chemical analysis typically use indirect potentiometry (involving te dilution of samples) to measure sodium levels, the equipment for measuring arterial blood gases use direct potentiometry without any dilution. Thus, results obtained with indirect potentiometry are expressed in molarity (per liter of plasma) while results obtained with direct potentiometry are initially given in morality (per kg of plasma water) then converted in molarity. Analytical performances are in all cases satisfactory and therefore all the methods could be used in both normal and pathological ranges. Methods involving sample dilution such as flame photometry or indirect potentiometry, the serum sodium value would be expected to be low in case of decrease plasma water (pseudohyponatremia). By contrast, with direct potentiometry where no sample dilution takes place, no interference would be expected since the activity of sodium in the water phase only is being measured. Thus, the classical pseudohyponatremia observed with hyperlipemia or paraproteinemia are not further observed with direct potentiometry. These differences in methodology should be taken into account to explain discrepancies between results obtained with classical biochemistry analyser and with blood gas apparatus.

  7. Factors determining working satisfaction

    OpenAIRE

    Nováčková, Radka

    2014-01-01

    This thesis is focused on the job satisfaction of employees in the selected organization. This organization is a company Cinema City Czech a limited lability. Specifically the thesis deals with job satisfaction of employees in multiplexes in six prague´s locations. The teoretical part is based on description of individual factors that affect job satisfaction. These are the condition of workplace, job content, financial rewards etc. Thesis is also focused on the motivation and important b...

  8. Biological risk factors for suicidal behaviors: a meta-analysis.

    Science.gov (United States)

    Chang, B P; Franklin, J C; Ribeiro, J D; Fox, K R; Bentley, K H; Kleiman, E M; Nock, M K

    2016-01-01

    Prior studies have proposed a wide range of potential biological risk factors for future suicidal behaviors. Although strong evidence exists for biological correlates of suicidal behaviors, it remains unclear if these correlates are also risk factors for suicidal behaviors. We performed a meta-analysis to integrate the existing literature on biological risk factors for suicidal behaviors and to determine their statistical significance. We conducted a systematic search of PubMed, PsycInfo and Google Scholar for studies that used a biological factor to predict either suicide attempt or death by suicide. Inclusion criteria included studies with at least one longitudinal analysis using a biological factor to predict either of these outcomes in any population through 2015. From an initial screen of 2541 studies we identified 94 cases. Random effects models were used for both meta-analyses and meta-regression. The combined effect of biological factors produced statistically significant but relatively weak prediction of suicide attempts (weighted mean odds ratio (wOR)=1.41; CI: 1.09-1.81) and suicide death (wOR=1.28; CI: 1.13-1.45). After accounting for publication bias, prediction was nonsignificant for both suicide attempts and suicide death. Only two factors remained significant after accounting for publication bias-cytokines (wOR=2.87; CI: 1.40-5.93) and low levels of fish oil nutrients (wOR=1.09; CI: 1.01-1.19). Our meta-analysis revealed that currently known biological factors are weak predictors of future suicidal behaviors. This conclusion should be interpreted within the context of the limitations of the existing literature, including long follow-up intervals and a lack of tests of interactions with other risk factors. Future studies addressing these limitations may more effectively test for potential biological risk factors. PMID:27622931

  9. Factores biológicos que determinan la competencia de Commelina erecta con otras malezas en sistemas de cultivo Biological factors determining Commelina erecta competition with other weeds in cultivated systems

    Directory of Open Access Journals (Sweden)

    L. Nisensohn

    2011-03-01

    all species fitted to a sigmoidal model. The RY of the different species varied relative to the accompanying species, the sampling date and the year. Competition was partial (RYT > 1 only in mixtures including C. erecta plants originated from rhizomes. From the simulations with the model it was determined that the result of the competition depends on the initial size (BI of C. erecta rhizomes. Furthermore, the sensibility analysis highlights the importance of the intrinsic growth rate (r in the definition of RY. Under competition conditions the biological parameters defining the growth of the species studied were particularly r and BI. The results emphasize the complex interaction of the factors determining the competitive balance, between both propagation forms of C. erecta, and between those forms and other weed species.

  10. Biological risk factors for deep vein trombosis.

    Science.gov (United States)

    Vayá, Amparo; Mira, Yolanda; Martínez, Marcial; Villa, Piedad; Ferrando, Fernando; Estellés, Amparo; Corella, Dolores; Aznar, Justo

    2002-01-01

    Hypercoagulable states due either to inherited or acquired thrombotic risk factors are only present in approximately half of cases of DVT, but the causes in the other half, remain unknown. The importance of biological risk factors such as hyperlipidemia, hypofibrinolysis and hemorheological alterations in the pathogenesis of DVT has not been well established. In order to ascertain whether the above mentioned biological factors are associated with DVT and could constitute independent risk factors, we carried out a case-control study in 109 first DVT patients in whom inherited or acquired thrombophilic risk factors had been ruled out and 121 healthy controls age (42+/-15 years) and sex matched. From all the biological variables analyzed (cholesterol, triglycerides, glucose, fibrinogen, erythrocyte aggregation, hematocrit, plasma viscosity and PAI-1) only fibrinogen concentration reached a statistically significant difference on the comparison of means (290+/-73 mg/dl in cases vs 268+/-58 mg/dl in controls, p220 mg/dl, hematocrit >45% and fibrinogen >300 mg/dl was higher in cases than in controls: 38% vs 22%; p30 ng/ml, 37% vs 25% was borderline significant; p=0.055. Multivariate logistic regression analysis showed that cholesterolemia >220 mg/dl and fibrinogen >300 mg/dl constitute independent predictors of venous thrombotic risk. The adjusted OR's were 2.03 (95% CI; 1.12-3.70) for cholesterolemia and 1.94 (95% CI; 1.07-3.55) for fibrinogen. When these two variables combined DVT risk rose about fourfold (3.96; p<0.05). Our results suggest that hypercholesterolemia and hyperfibrinogenemia should be added to the list of known DVT risk factors and we recommend adopting measures to decrease these variables in the population with a high risk of DVT.

  11. Determining Factors of Subsidiary Development

    DEFF Research Database (Denmark)

    Pedersen, Torben

    (the depth of activities) and level of integration in the internal MNC-network. Birkinshaw and Hood (1998a) have in their seminal paper proposed a model where subsidiary development is determined by three factors: Headquarter assignment, dynamism of local business environment and subsidiary initiatives......Subsidiary development is a multi-dimensional construct that cannot be captured just by looking at subsidiary roles, activities, etc. Three distinct dimensions of subsidiary development are identified and these are: scope of subsidiary (the breadth of activities), level of subsidiary competence...

  12. Neuronal factors determining high intelligence.

    Science.gov (United States)

    Dicke, Ursula; Roth, Gerhard

    2016-01-01

    Many attempts have been made to correlate degrees of both animal and human intelligence with brain properties. With respect to mammals, a much-discussed trait concerns absolute and relative brain size, either uncorrected or corrected for body size. However, the correlation of both with degrees of intelligence yields large inconsistencies, because although they are regarded as the most intelligent mammals, monkeys and apes, including humans, have neither the absolutely nor the relatively largest brains. The best fit between brain traits and degrees of intelligence among mammals is reached by a combination of the number of cortical neurons, neuron packing density, interneuronal distance and axonal conduction velocity--factors that determine general information processing capacity (IPC), as reflected by general intelligence. The highest IPC is found in humans, followed by the great apes, Old World and New World monkeys. The IPC of cetaceans and elephants is much lower because of a thin cortex, low neuron packing density and low axonal conduction velocity. By contrast, corvid and psittacid birds have very small and densely packed pallial neurons and relatively many neurons, which, despite very small brain volumes, might explain their high intelligence. The evolution of a syntactical and grammatical language in humans most probably has served as an additional intelligence amplifier, which may have happened in songbirds and psittacids in a convergent manner. PMID:26598734

  13. The biology of melanoma prognostic factors.

    NARCIS (Netherlands)

    Spatz, A.; Stock, N.; Batist, G.; Kempen, L.C.L.T. van

    2010-01-01

    Cutaneous melanoma still represents a paradox among all solid tumors. It is the cancer for which the best prognostic markers ever identified in solid tumors are available, yet there is very little understanding of their biological significance. This review focuses on recent biological data that shed

  14. Fano factor determination for CZT

    International Nuclear Information System (INIS)

    Continued improvements in the manufacturing of Cd1-xZnxTe (CZT) material have resulted in a practical thermoelectrically cooled X-ray and gamma-ray detector of very high energy resolution. A high resolution spectroscopy system was used to measure the Fano factor in CZT at temperatures down to -40 C. The best resolution of the 5.9 keV 55Fe peak was measured to be 188 eV FWHM, while the best resolution of the 59.5 keV 241Am peak was measured to be 482 eV FWHM. The minimum measured Fano factor was 0.082, with several measurements yielding a value of 0.089 ± 0.005. With a resolution of 4.2 keV FWHM for the 662 keV peak of 137Cs, these detectors demonstrate excellent performance in detecting X-rays and gamma rays

  15. ALOUD biological: Adult Learning Open University Determinants study - Association of biological determinants with study success in formal lifelong learners

    NARCIS (Netherlands)

    Gijselaers, Jérôme; De Groot, Renate; Kirschner, Paul A.

    2012-01-01

    Gijselaers, H. J. M., De Groot, R. H. M., & Kirschner, P. A. (2012, 15 March). ALOUD biological: Adult Learning Open University Determinants study - Association of biological determinants with study success in formal lifelong learners. Presentation given at the plenary meeting of Learning & Cognitio

  16. Determination of cadmium in biological samples.

    Science.gov (United States)

    Klotz, Katrin; Weistenhöfer, Wobbeke; Drexler, Hans

    2013-01-01

    Analyses of cadmium concentrations in biological material are performed using inductively coupled plasma mass spectrometry (ICP-MS) and atomic absorption spectrometry (AAS), but also electrochemical methods, neutron activation analysis (NAA), and X-ray fluorescence spectrometry (XRF). The predominant sample matrices include blood, plasma, serum, and urine, as well as hair, saliva, and tissue of kidney cortex, lung, and liver. While cadmium in blood reveals rather the recent exposure situation, cadmium in urine reflects the body burden and is an indicator for the cumulative long term exposure.After chronic exposure, cadmium accumulates in the human body and causes kidney diseases, especially lesions of proximal tubular cells. A tubular proteinuria causes an increase in urinary excretion of microproteins. Excretions of retinol binding protein (RBP), β2-microglobulin (β2-M), and α1-microglobulin are validated biomarkers for analyzing cadmium effects. For this purpose, immunological procedures such as ELISA, and radio- and latex-immunoassays are used.However, proteinuria is not specific to cadmium, but can also occur after exposure to other nephrotoxic agents or due to various kidney diseases. In summary, cadmium in urine and blood are the most specific biomarkers of cadmium exposure. A combination of parameters of exposure (cadmium in blood, cadmium in urine) and parameters of effect (e.g., β2-M, RBP) is required to reveal cadmium-induced nephrological effects. PMID:23430771

  17. Transcriptional factors, Mafs and their biological roles

    Institute of Scientific and Technical Information of China (English)

    Mariko Tsuchiya; Ryoichi Misaka; Kosaku Nitta; Ken Tsuchiya

    2015-01-01

    The Maf family of transcription factors is characterizedby a typical bZip structure; these transcription factorsact as important regulators of the development anddifferentiation of many organs and tissues, includingthe kidney. The Maf family consists of two subgroupsthat are characterized according to their structure largeMaf transcription factors and small Maf transcriptionfactors. The large Maf subgroup consists of fourproteins, designated as MAFA, MAFB, c-MAF and neuralretina-specific leucine zipper. In particular, MAFA is adistinct molecule that has been attracting the attentionof researchers because it acts as a strong transactivatorof insulin, suggesting that Maf transcription factors arelikely to be involved in systemic energy homeostasis. Inthis review, we focused on the regulation of glucose/energy balance by Maf transcription factors in variousorgans.

  18. Driving Style: Determining Factors, Characteristics, Optimization Directions

    OpenAIRE

    Lobanova I. I.

    2015-01-01

    A system of description, identification and classification of factors determining driving style is proposed in the article; stable (sustained) and variable (unstable) factors determining driving style are studied. Driving style is analyzed within the framework of structural approach. The variable factor are: specifications and technical condition of the vehicle, class of the car, its prestige (from a social point of view), training of the driver, social regulators, features of the road enviro...

  19. Acciones biológicas y factores determinantes de las concentraciones del factor de crecimiento similar a la insulina tipo I (IGF-1 en el caballo (Biological actions and determinant factors of the circulating concentrations of insulin-like growth factor type 1, IGF-1, in the horse

    Directory of Open Access Journals (Sweden)

    Muñoz A

    2010-06-01

    activity of the hypophysis and the somatotropic axis. In the present review, firstly, we will describe the main biological actions of the IGF-1 and secondly, we will define the main factors that could significantly influence the circulating concentrations of IGF-1. Among these factors, the most important are body size, breed, age, gender, time of blood extraction, circadianrhythms, diet, food privation, exercise and training. The effect of these factors should be assessed prior to extended clinical and research use of IGF-1 in horses.

  20. Happiness & Health: The Biological Factors- Systematic Review Article.

    Directory of Open Access Journals (Sweden)

    Dariush Dfarhud

    2014-11-01

    Full Text Available Happiness underlying factors are considerable from two dimensions: endogenic factors (biological, cognitive, personality and ethical sub-factors and exogenic factors (behavioral, socialcultural, economical, geographical, life events and aesthetics sub-factors. Among all endogenic factors, biological sub-factors are the significant predictors of happiness. Existence of significant differences in temperament and happiness of infants is an indicator of biological influences. Therefore, this study aimed to consider biological factors that underlie happiness. At the first, all of the biological factors in relation with happiness were searched from following websites: PubMed, Wiley& Sons, Science direct (1990-2014. Then, the articles divided into five sub-groups (genetic, brain and neurotransmitters, endocrinology and hormones, physical health, morphology and physical attractiveness. Finally, a systematic review performed based on existing information. Results of studies on genetic factors indicated an average effectiveness of genetic about 35 -50 percent on happiness. In spite of difficulties in finding special genes, several genes distributed to emotion and mood. Neuroscience studies showed that some part of brain (e.g. amygdala, hipocamp and limbic system and neurotransmitters (e.g. dopamine, serotonin, norepinefrine and endorphin play a role in control of happiness. A few studies pointed to the role of cortisol and adrenaline (adrenal gland and oxitocin (pituitary gland in controlling happiness. Physical health and typology also concluded in most related studies to have a significant role in happiness. Therefore, according to previous research, it can be said that biological and health factors are critical in underlying happiness and its role in happiness is undeniable.

  1. Happiness & Health: The Biological Factors- Systematic Review Article.

    Science.gov (United States)

    Dfarhud, Dariush; Malmir, Maryam; Khanahmadi, Mohammad

    2014-11-01

    Happiness underlying factors are considerable from two dimensions: endogenic factors (biological, cognitive, personality and ethical sub-factors) and exogenic factors (behavioral, socialcultural, economical, geographical, life events and aesthetics sub-factors). Among all endogenic factors, biological sub-factors are the significant predictors of happiness. Existence of significant differences in temperament and happiness of infants is an indicator of biological influences. Therefore, this study aimed to consider biological factors that underlie happiness. At the first, all of the biological factors in relation with happiness were searched from following websites: PubMed, Wiley& Sons, Science direct (1990-2014). Then, the articles divided into five sub-groups (genetic, brain and neurotransmitters, endocrinology and hormones, physical health, morphology and physical attractiveness). Finally, a systematic review performed based on existing information. Results of studies on genetic factors indicated an average effectiveness of genetic about 35 -50 percent on happiness. In spite of difficulties in finding special genes, several genes distributed to emotion and mood. Neuroscience studies showed that some part of brain (e.g. amygdala, hipocamp and limbic system) and neurotransmitters (e.g. dopamine, serotonin, norepinefrine and endorphin) play a role in control of happiness. A few studies pointed to the role of cortisol and adrenaline (adrenal gland) and oxitocin (pituitary gland) in controlling happiness. Physical health and typology also concluded in most related studies to have a significant role in happiness. Therefore, according to previous research, it can be said that biological and health factors are critical in underlying happiness and its role in happiness is undeniable. PMID:26060713

  2. Cone Penetrometer N Factor Determination Testing Results

    Energy Technology Data Exchange (ETDEWEB)

    Follett, Jordan R.

    2014-03-05

    This document contains the results of testing activities to determine the empirical 'N Factor' for the cone penetrometer in kaolin clay simulant. The N Factor is used to releate resistance measurements taken with the cone penetrometer to shear strength.

  3. Factors affecting response to biologic treatment in psoriasis.

    Science.gov (United States)

    Karczewski, Jacek; Poniedziałek, Barbara; Rzymski, Piotr; Adamski, Zygmunt

    2014-01-01

    Psoriasis is a chronic, immune-mediated inflammatory skin disease, affecting approximately 2-4% of the population in western countries. Patients with a more severe form of the disease are typically considered for systemic therapy, including biologics. In spite of the overall superiority of biologic agents, the treatment response may differ substantially among individual patients. As with other medical conditions, a range of factors contribute to response heterogeneity observed in psoriasis. Proper identification of these factors can significantly improve the therapeutic decisions. This review focuses on potential genetic and nongenetic factors that may affect the treatment response and outcomes in patients with psoriasis.

  4. Development of methods for determining aflatoxins in biological material

    OpenAIRE

    Kussak, Anders

    1995-01-01

    In this thesis, it is shown how aflatoxins can be determined in biological material. The thesis is a summary of five papers. Aflatoxins are carcinogenic mycotoxins produced by Aspergillus moulds. Methods were developed for the determination of aflatoxins in samples of airborne dust and human urine collected at feed factories. For the dust samples from such agricultural products as copra, cotton seed and maize, methods were developed for the determination of aflatoxins B1, B2, G1 and G2. For u...

  5. Topography and biological noise determine acoustic detectability on coral reefs

    KAUST Repository

    Cagua, Edgar F.

    2013-08-19

    Acoustic telemetry is an increasingly common tool for studying the movement patterns, behavior and site fidelity of marine organisms, but to accurately interpret acoustic data, the variability, periodicity and range of detectability between acoustic tags and receivers must be understood. The relative and interactive effects of topography with biological and environmental noise have not been quantified on coral reefs. We conduct two long-term range tests (1- and 4-month duration) on two different reef types in the central Red Sea to determine the relative effect of distance, depth, topography, time of day, wind, lunar phase, sea surface temperature and thermocline on detection probability. Detectability, as expected, declines with increasing distance between tags and receivers, and we find average detection ranges of 530 and 120 m, using V16 and V13 tags, respectively, but the topography of the reef can significantly modify this relationship, reducing the range by ~70 %, even when tags and receivers are in line-of-sight. Analyses that assume a relationship between distance and detections must therefore be used with care. Nighttime detection range was consistently reduced in both locations, and detections varied by lunar phase in the 4-month test, suggesting a strong influence of biological noise (reducing detection probability up to 30 %), notably more influential than other environmental noises, including wind-driven noise, which is normally considered important in open-water environments. Analysis of detections should be corrected in consideration of the diel patterns we find, and range tests or sentinel tags should be used for more than 1 month to quantify potential changes due to lunar phase. Some studies assume that the most usual factor limiting detection range is weather-related noise; this cannot be extrapolated to coral reefs. © 2013 Springer-Verlag Berlin Heidelberg.

  6. Social, Behavioral, and Biological Factors, and Sex Differences in Mortality

    OpenAIRE

    Rogers, Richard G.; Everett, Bethany G.; Saint Onge, Jarron M.; Krueger, Patrick M.

    2010-01-01

    Few studies have examined whether sex differences in mortality are associated with different distributions of risk factors or result from the unique relationships between risk factors and mortality for men and women. We extend previous research by systematically testing a variety of factors, including health behaviors, social ties, socioeconomic status, and biological indicators of health. We employ the National Health and Nutritional Examination Survey III Linked Mortality File and use Cox p...

  7. Fibroblast Growth Factors: Biology, Function, and Application for Tissue Regeneration

    OpenAIRE

    Ye-Rang Yun; Jong Eun Won; Eunyi Jeon; Sujin Lee; Wonmo Kang; Hyejin Jo; Jun-Hyeog Jang; Ueon Sang Shin; Hae-Won Kim

    2010-01-01

    Fibroblast growth factors (FGFs) that signal through FGF receptors (FGFRs) regulate a broad spectrum of biological functions, including cellular proliferation, survival, migration, and differentiation. The FGF signal pathways are the RAS/MAP kinase pathway, PI3 kinase/AKT pathway, and PLCγ pathway, among which the RAS/MAP kinase pathway is known to be predominant. Several studies have recently implicated the in vitro biological functions of FGFs for tissue regeneration. However, to obtain opt...

  8. Student Perceived and Determined Knowledge of Biology Concepts in an Upper-Level Biology Course

    Science.gov (United States)

    Ziegler, Brittany; Montplaisir, Lisa

    2014-01-01

    Students who lack metacognitive skills can struggle with the learning process. To be effective learners, students should recognize what they know and what they do not know. This study examines the relationship between students' perception of their knowledge and determined knowledge in an upper-level biology course utilizing a pre/posttest…

  9. Transitional cell carcinoma of the bladder : histopathological and biological factors and prognosis

    NARCIS (Netherlands)

    R.F.M. Schapers

    1993-01-01

    textabstractThe main purpose of the studies reported in this thesis has been to determine the extent to which the behaviour of TCC can be predicted by histopathological and biological characteristics. The potential additional prognostic value of these factors was evaluated by combining them with oth

  10. The potential for biological structure determination with pulsed neutrons

    International Nuclear Information System (INIS)

    The potential of pulsed neutron diffraction in structural determination of biological materials is discussed. The problems and potential solutions in this area are outlined, with reference to both current and future sources and instrumentation. The importance of developing instrumentation on pulsed sources in emphasized, with reference to the likelihood of future expansion in this area. The possibilities and limitations of single crystal, fiber and powder diffraction in this area are assessed

  11. The potential for biological structure determination with pulsed neutrons

    Energy Technology Data Exchange (ETDEWEB)

    Wilson, C.C. [CLRC Rutherford Appleton Laboratory, Chilton Didcot Oxon (United Kingdom)

    1994-12-31

    The potential of pulsed neutron diffraction in structural determination of biological materials is discussed. The problems and potential solutions in this area are outlined, with reference to both current and future sources and instrumentation. The importance of developing instrumentation on pulsed sources in emphasized, with reference to the likelihood of future expansion in this area. The possibilities and limitations of single crystal, fiber and powder diffraction in this area are assessed.

  12. Running economy: measurement, norms, and determining factors

    OpenAIRE

    Barnes, Kyle R; Kilding, Andrew E.

    2015-01-01

    Running economy (RE) is considered an important physiological measure for endurance athletes, especially distance runners. This review considers 1) how RE is defined and measured and 2) physiological and biomechanical factors that determine or influence RE. It is difficult to accurately ascertain what is good, average, and poor RE between athletes and studies due to variation in protocols, gas-analysis systems, and data averaging techniques. However, representative RE values for different cal...

  13. Biological Stability of Drinking Water: Controlling Factors, Methods, and Challenges

    KAUST Repository

    Prest, Emmanuelle I.

    2016-02-01

    Biological stability of drinking water refers to the concept of providing consumers with drinking water of same microbial quality at the tap as produced at the water treatment facility. However, uncontrolled growth of bacteria can occur during distribution in water mains and premise plumbing, and can lead to hygienic (e.g., development of opportunistic pathogens), aesthetic (e.g., deterioration of taste, odor, color) or operational (e.g., fouling or biocorrosion of pipes) problems. Drinking water contains diverse microorganisms competing for limited available nutrients for growth. Bacterial growth and interactions are regulated by factors, such as (i) type and concentration of available organic and inorganic nutrients, (ii) type and concentration of residual disinfectant, (iii) presence of predators, such as protozoa and invertebrates, (iv) environmental conditions, such as water temperature, and (v) spatial location of microorganisms (bulk water, sediment, or biofilm). Water treatment and distribution conditions in water mains and premise plumbing affect each of these factors and shape bacterial community characteristics (abundance, composition, viability) in distribution systems. Improved understanding of bacterial interactions in distribution systems and of environmental conditions impact is needed for better control of bacterial communities during drinking water production and distribution. This article reviews (i) existing knowledge on biological stability controlling factors and (ii) how these factors are affected by drinking water production and distribution conditions. In addition, (iii) the concept of biological stability is discussed in light of experience with well-established and new analytical methods, enabling high throughput analysis and in-depth characterization of bacterial communities in drinking water. We discussed, how knowledge gained from novel techniques will improve design and monitoring of water treatment and distribution systems in order

  14. Molecular biological factors in the diagnosis of cervical intraepithelial neoplasias

    Directory of Open Access Journals (Sweden)

    Yu. N. Ponomareva

    2010-01-01

    Full Text Available The authors have made a complex analysis of the molecular biological factors associated with cervical intraepithelial neoplasia. They have revealed that infection by oncogenic human papillomavirus types is associated with suppressed apoptosis and enhanced cellular proliferative activity, which can be effectively used in the diagnosis and prediction of cervical neoplasias to optimize management tac- tics and to improve the results of treatment.

  15. Biological Stability of Drinking Water: Controlling Factors, Methods, and Challenges.

    Science.gov (United States)

    Prest, Emmanuelle I; Hammes, Frederik; van Loosdrecht, Mark C M; Vrouwenvelder, Johannes S

    2016-01-01

    Biological stability of drinking water refers to the concept of providing consumers with drinking water of same microbial quality at the tap as produced at the water treatment facility. However, uncontrolled growth of bacteria can occur during distribution in water mains and premise plumbing, and can lead to hygienic (e.g., development of opportunistic pathogens), aesthetic (e.g., deterioration of taste, odor, color) or operational (e.g., fouling or biocorrosion of pipes) problems. Drinking water contains diverse microorganisms competing for limited available nutrients for growth. Bacterial growth and interactions are regulated by factors, such as (i) type and concentration of available organic and inorganic nutrients, (ii) type and concentration of residual disinfectant, (iii) presence of predators, such as protozoa and invertebrates, (iv) environmental conditions, such as water temperature, and (v) spatial location of microorganisms (bulk water, sediment, or biofilm). Water treatment and distribution conditions in water mains and premise plumbing affect each of these factors and shape bacterial community characteristics (abundance, composition, viability) in distribution systems. Improved understanding of bacterial interactions in distribution systems and of environmental conditions impact is needed for better control of bacterial communities during drinking water production and distribution. This article reviews (i) existing knowledge on biological stability controlling factors and (ii) how these factors are affected by drinking water production and distribution conditions. In addition, (iii) the concept of biological stability is discussed in light of experience with well-established and new analytical methods, enabling high throughput analysis and in-depth characterization of bacterial communities in drinking water. We discussed, how knowledge gained from novel techniques will improve design and monitoring of water treatment and distribution systems in order

  16. Biological Stability of Drinking Water: Controlling Factors, Methods, and Challenges

    Science.gov (United States)

    Prest, Emmanuelle I.; Hammes, Frederik; van Loosdrecht, Mark C. M.; Vrouwenvelder, Johannes S.

    2016-01-01

    Biological stability of drinking water refers to the concept of providing consumers with drinking water of same microbial quality at the tap as produced at the water treatment facility. However, uncontrolled growth of bacteria can occur during distribution in water mains and premise plumbing, and can lead to hygienic (e.g., development of opportunistic pathogens), aesthetic (e.g., deterioration of taste, odor, color) or operational (e.g., fouling or biocorrosion of pipes) problems. Drinking water contains diverse microorganisms competing for limited available nutrients for growth. Bacterial growth and interactions are regulated by factors, such as (i) type and concentration of available organic and inorganic nutrients, (ii) type and concentration of residual disinfectant, (iii) presence of predators, such as protozoa and invertebrates, (iv) environmental conditions, such as water temperature, and (v) spatial location of microorganisms (bulk water, sediment, or biofilm). Water treatment and distribution conditions in water mains and premise plumbing affect each of these factors and shape bacterial community characteristics (abundance, composition, viability) in distribution systems. Improved understanding of bacterial interactions in distribution systems and of environmental conditions impact is needed for better control of bacterial communities during drinking water production and distribution. This article reviews (i) existing knowledge on biological stability controlling factors and (ii) how these factors are affected by drinking water production and distribution conditions. In addition, (iii) the concept of biological stability is discussed in light of experience with well-established and new analytical methods, enabling high throughput analysis and in-depth characterization of bacterial communities in drinking water. We discussed, how knowledge gained from novel techniques will improve design and monitoring of water treatment and distribution systems in order

  17. Biological stability of drinking water: controlling factors, methods and challenges

    Directory of Open Access Journals (Sweden)

    Emmanuelle ePrest

    2016-02-01

    Full Text Available Biological stability of drinking water refers to the concept of providing consumers with drinking water of same microbial quality at the tap as produced at the water treatment facility. However, uncontrolled growth of bacteria can occur during distribution in water mains and premise plumbing, and can lead to hygienic (e.g. development of opportunistic pathogens, aesthetic (e.g. deterioration of taste, odour, colour or operational (e.g. fouling or biocorrosion of pipes problems. Drinking water contains diverse microorganisms competing for limited available nutrients for growth. Bacterial growth and interactions are regulated by factors such as (i type and concentration of available organic and inorganic nutrients, (ii type and concentration of residual disinfectant, (iii presence of predators such as protozoa and invertebrates, (iv environmental conditions such as water temperature, and (v spatial location of microorganisms (bulk water, sediment or biofilm. Water treatment and distribution conditions in water mains and premise plumbing affect each of these factors and shape bacterial community characteristics (abundance, composition, viability in distribution systems. Improved understanding of bacterial interactions in distribution systems and of environmental conditions impact is needed for better control of bacterial communities during drinking water production and distribution. This article reviews (i existing knowledge on biological stability controlling factors and (ii how these factors are affected by drinking water production and distribution conditions. In addition, (iii the concept of biological stability is discussed in light of experience with well-established and new analytical methods, enabling high throughput analysis and in-depth characterization of bacterial communities in drinking water. We discuss how knowledge gained from novel techniques will improve design and monitoring of water treatment and distribution systems in order to

  18. DETERMINATION OF RELATIVE IMPORTANCE OF NONPROLIFERATION FACTORS

    Energy Technology Data Exchange (ETDEWEB)

    Richard Metcalf

    2009-07-01

    Methodologies to determine the proliferation resistance (PR) of nuclear facilities often rely on either expert elicitation, a resource-intensive approach without easily reproducible results, or numeric evaluations, which can fail to take into account the institutional knowledge and expert experience of the nonproliferation community. In an attempt to bridge the gap and bring the institutional knowledge into numeric evaluations of PR, a survey was conducted of 33 individuals to find the relative importance of a set of 62 nonproliferation factors, subsectioned into groups under the headings of Diversion, Transportation, Transformation, and Weaponization. One third of the respondents were self-described nonproliferation professionals, and the remaining two thirds were from secondary professions related to nonproliferation, such as industrial engineers or policy analysts. The factors were taken from previous work which used multi-attribute utility analysis with uniform weighting of attributes and did not include institutional knowledge. In both expert and non-expert groups, all four headings and the majority of factors had different relative importance at a confidence of 95% (p=0.05). This analysis and survey demonstrates that institutional knowledge can be brought into numeric evaluations of PR, if there is a sufficient investment of resources made prior to the evaluation.

  19. Possibilities of nondestructive determination of fluorine in coal and biological materials by IPAA

    International Nuclear Information System (INIS)

    The possibilities of nondestructive determination of fluorine in coal and biological materials by instrumental photon activation analysis (IPAA) were studied. The determination was based on counting the non-specific 511 keV annihilation gamma rays of 18F, a pure positron emitter which is the product of the photonuclear reaction 19F(γ, n)18F. The simultaneous formation of some additional positron emitters, particularly 45Ti and 34mCl, is an interfering factor. When using correction standards for Ti and Cl and optimization of the beam energy and irradiation-decay-counting times, fluorine could be determined by IPAA in selected coal and biological samples at the ten ppm level. The feasibility of additional optimization for further improvements of the proposed IPAA procedure are discussed

  20. Psychosocial job factors and biological cardiovascular risk factors in Mexican workers

    OpenAIRE

    Garcia-Rojas, IJ; Choi, B; Krause, N.

    2015-01-01

    © 2015 Wiley Periodicals, Inc. Background: Psychosocial job factors (PJF) have been implicated in the development of cardiovascular disease. The paucity of data from developing economies including Mexico hampers the development of worksite intervention efforts in those regions. Methods: This cross-sectional study of 2,330 Mexican workers assessed PJF (job strain [JS], social support [SS], and job insecurity [JI]) and biological cardiovascular disease risk factors [CVDRF] by questionnaire and ...

  1. Some Limitations of BIOLOG System for Determining Soil Microbial Community

    Institute of Scientific and Technical Information of China (English)

    2000-01-01

    A laboratory experiment was conducted to evaluate the effect of triphenyltetrazolium chloride (TTC)on soil microorganisms and the availability of pH characterization medium in BIOLOG plates. Applicationof TTC decreased the color development sharply and resulted in a great biocidal effect on the growth andreproduction of soil microorganisms, indicating that TTC can affect the discrimination on soil microbialcommunity. The microtitration plates with 21 carbon sources and two different pH levels (4.7 and 7.0) wereused to determine microbial community structure of eight red soils. The average utilization (average wellcolour development) of the carbon sources in the plates with different pH levels generally followed the samesigmoidal pattern as that in the traditional BIOLOG plates, but the pH 4.7 plates increased the discrimination of this technique, compared with the pH 7.0 plates. Since most tested soils are acid, it seemed that it's better to use a suitable pH characterization medium for a specific soil in the sole carbon source test.

  2. Determinant Factors of Dividend Payments in Brazil

    Directory of Open Access Journals (Sweden)

    Cristiano Augusto Borges Forti

    2015-08-01

    Full Text Available This study identifies factors that shaped cash disbursement distribution policies employed by Brazilian public companies listed on the Brazilian Securities, Commodities and Futures Exchange (BM&FBOVESPA from 1995 to 2011. Relationships between Dividends/Total Assets and potential determinants discussed in the literature, including firm size, corporate governance, profitability, leverage, market to book, liquidity, investment, risk, profit growth, information asymmetry and agency conflict, are examined. The following econometric methods are employed: (1 Tobit, given the nature of the dividend data, and (2 the Generalized Method of Moments (GMM to control for endogenous regressors. Significant positive variables found include size, return on assets (ROA, market to book, liquidity and profit growth. It can thus be inferred that larger firm size, profitability, market value, liquidity and profit growth correlate with greater firm pro pensity to distribute money to shareholders, thus supporting the theory of corporate finance. Significant negative variables found include leverage, liquidity squared, capex, beta and tag along 100%. It is thus inferred that more significantly leveraged companies that invest more heavily in fixed assets and that exhibit high liquidity, higher risk and less conflict between controlling and minority shareholders will be less likely to pay dividends to shareholders.

  3. Classifying transcription factor targets and discovering relevant biological features

    Directory of Open Access Journals (Sweden)

    DeLisi Charles

    2008-05-01

    Full Text Available Abstract Background An important goal in post-genomic research is discovering the network of interactions between transcription factors (TFs and the genes they regulate. We have previously reported the development of a supervised-learning approach to TF target identification, and used it to predict targets of 104 transcription factors in yeast. We now include a new sequence conservation measure, expand our predictions to include 59 new TFs, introduce a web-server, and implement an improved ranking method to reveal the biological features contributing to regulation. The classifiers combine 8 genomic datasets covering a broad range of measurements including sequence conservation, sequence overrepresentation, gene expression, and DNA structural properties. Principal Findings (1 Application of the method yields an amplification of information about yeast regulators. The ratio of total targets to previously known targets is greater than 2 for 11 TFs, with several having larger gains: Ash1(4, Ino2(2.6, Yaf1(2.4, and Yap6(2.4. (2 Many predicted targets for TFs match well with the known biology of their regulators. As a case study we discuss the regulator Swi6, presenting evidence that it may be important in the DNA damage response, and that the previously uncharacterized gene YMR279C plays a role in DNA damage response and perhaps in cell-cycle progression. (3 A procedure based on recursive-feature-elimination is able to uncover from the large initial data sets those features that best distinguish targets for any TF, providing clues relevant to its biology. An analysis of Swi6 suggests a possible role in lipid metabolism, and more specifically in metabolism of ceramide, a bioactive lipid currently being investigated for anti-cancer properties. (4 An analysis of global network properties highlights the transcriptional network hubs; the factors which control the most genes and the genes which are bound by the largest set of regulators. Cell-cycle and

  4. Simultaneous determination of salicylic acid and salicylamide in biological fluids

    Science.gov (United States)

    Murillo Pulgarín, J. A.; Alañón Molina, A.; Sánchez-Ferrer Robles, I.

    2011-09-01

    A new methodology for the simultaneous determination of salicylic acid and salicylamide in biological fluids is proposed. The strong overlapping of the fluorescence spectra of both analytes makes impossible the conventional fluorimetric determination. For that reason, the use of fluorescence decay curves to resolve mixtures of analytes is proposed; this is a novel technique that provides the benefits in selectivity and sensitivity of the fluorescence decay curves. In order to assess the goodness of the proposed method, a prediction set of synthetic samples were analyzed obtaining recuperation percentages between 98.2 and 104.6%. Finally, a study of the detection limits was done using a new criterion resulting in values for the detection limits of 8.2 and 11.6 μg L -1 for salicylic acid and salicylamide respectively. The validity of the method was tested in human serum and human urine spiked with aliquots of the analytes. Recoveries obtained were 96.2 and 94.5% for salicylic acid and salicylamide respectively.

  5. Quantification of the impact of PSI:Biology according to the annotations of the determined structures

    OpenAIRE

    DePietro, Paul J; Julfayev, Elchin S.; McLaughlin, William A.

    2013-01-01

    Background Protein Structure Initiative:Biology (PSI:Biology) is the third phase of PSI where protein structures are determined in high-throughput to characterize their biological functions. The transition to the third phase entailed the formation of PSI:Biology Partnerships which are composed of structural genomics centers and biomedical science laboratories. We present a method to examine the impact of protein structures determined under the auspices of PSI:Biology by measuring their rates ...

  6. Factors Potentially Influencing Student Acceptance of Biological Evolution

    Science.gov (United States)

    Wiles, Jason R.

    This investigation explored scientific, religious, and otherwise nonscientific factors that may influence student acceptance of biological evolution and related concepts, how students perceived these factors to have influenced their levels of acceptance of evolution and changes therein, and what patterns arose among students' articulations of how their levels of acceptance of evolution may have changed. This exploration also measured the extent to which students' levels of acceptance changed following a treatment designed to address factors identified as potentially affecting student acceptance of evolution. Acceptance of evolution was measured using the MATE instrument (Rutledge and Warden, 1999; Rutledge and Sadler, 2007) among participants enrolled in a secondary-level academic program during the summer prior to their final year of high school and as they transitioned to the post-secondary level. Student acceptance of evolution was measured to be significantly higher than pre-treatment levels both immediately following and slightly over one year after treatment. Qualitative data from informal questionnaires, from formal course evaluations, and from semi-structured interviews of students engaged in secondary level education and former students at various stages of post-secondary education confirmed that the suspected factors were perceived by participants to have influenced their levels of acceptance of evolution. Furthermore, participant reports provided insight regarding the relative effects they perceived these factors to have had on their evolution acceptance levels. Additionally, many participants reported that their science teachers in public schools had avoided, omitted, or denigrated evolution during instruction, and several of these students expressed frustration regarding what they perceived to have been a lack of education of an important scientific principle. Finally, no students expressed feelings of being offended by having been taught about

  7. Extracellular Vesicles: Evolving Factors in Stem Cell Biology

    Science.gov (United States)

    Nawaz, Muhammad; Fatima, Farah; Vallabhaneni, Krishna C.; Penfornis, Patrice; Valadi, Hadi; Ekström, Karin; Kholia, Sharad; Whitt, Jason D.; Fernandes, Joseph D.; Pochampally, Radhika; Squire, Jeremy A.; Camussi, Giovanni

    2016-01-01

    Stem cells are proposed to continuously secrete trophic factors that potentially serve as mediators of autocrine and paracrine activities, associated with reprogramming of the tumor microenvironment, tissue regeneration, and repair. Hitherto, significant efforts have been made to understand the level of underlying paracrine activities influenced by stem cell secreted trophic factors, as little is known about these interactions. Recent findings, however, elucidate this role by reporting the effects of stem cell derived extracellular vesicles (EVs) that mimic the phenotypes of the cells from which they originate. Exchange of genetic information utilizing persistent bidirectional communication mediated by stem cell-EVs could regulate stemness, self-renewal, and differentiation in stem cells and their subpopulations. This review therefore discusses stem cell-EVs as evolving communication factors in stem cell biology, focusing on how they regulate cell fates by inducing persistent and prolonged genetic reprogramming of resident cells in a paracrine fashion. In addition, we address the role of stem cell-secreted vesicles in shaping the tumor microenvironment and immunomodulation and in their ability to stimulate endogenous repair processes during tissue damage. Collectively, these functions ensure an enormous potential for future therapies. PMID:26649044

  8. Factors influencing biological treatment of MTBE contaminated ground water

    Energy Technology Data Exchange (ETDEWEB)

    Stringfellow, William T.; Hines Jr., Robert D.; Cockrum, Dirk K.; Kilkenny, Scott T.

    2001-09-14

    Methyl tert-butyl ether (MTBE) contamination has complicated the remediation of gasoline contaminated sites. Many sites are using biological processes for ground water treatment and would like to apply the same technology to MTBE. However, the efficiency and reliability of MTBE biological treatment is not well documented. The objective of this study was to examine the operational and environmental variables influencing MTBE biotreatment. A fluidized bed reactor was installed at a fuel transfer station and used to treat ground water contaminated with MTBE and gasoline hydrocarbons. A complete set of chemical and operational data was collected during this study and a statistical approach was used to determine what variables were influencing MTBE treatment efficiency. It was found that MTBE treatment was more sensitive to up-set than gasoline hydrocarbon treatment. Events, such as excess iron accumulation, inhibited MTBE treatment, but not hydrocarbon treatment. Multiple regression analysis identified biomass accumulation and temperature as the most important variables controlling the efficiency of MTBE treatment. The influent concentration and loading of hydrocarbons, but not MTBE, also impacted MTBE treatment efficiency. The results of this study suggest guidelines for improving MTBE treatment. Long cell retention times in the reactor are necessary for maintaining MTBE treatment. The onset of nitrification only occurs when long cell retention times have been reached and can be used as an indicator in fixed film reactors that conditions favorable to MTBE treatment exist. Conversely, if the reactor can not nitrify, it is unlikely to have stable MTBE treatment.

  9. DETERMINANT OF INCENTIVE FACTORS IN KNOWLEDGE SHARING

    OpenAIRE

    Ali Reza Heydari ,Hamed Armesh ,Saied Behjatie, Mahmoud Manafi

    2011-01-01

    In this uncertain economic climate, knowledge has a key role, where it emerges as an asset. Land, labor, and capital are not as significant resources as they were before. Land, labor, and capital - the classical factors of production - have become secondary to knowledge as the primary resource for the new economy (Drucker, 1992). This study mainly examines the factors affecting the incentives factors of organizational members to share knowledge via MMU knowledge sharing system. The main focus...

  10. Clinical and Biological Risk Factors for Neuropsychological Impairment in Alcohol Use Disorder.

    Science.gov (United States)

    Ritz, Ludivine; Coulbault, Laurent; Lannuzel, Coralie; Boudehent, Céline; Segobin, Shailendra; Eustache, Francis; Vabret, François; Pitel, Anne Lise; Beaunieux, Hélène

    2016-01-01

    The effects of alcoholism on cognitive and motor functioning are heterogeneous. While the role of some factors (patterns of alcohol consumption, eating habits or associated liver disease) has been hypothesized, the origins of this heterogeneity remain difficult to establish. The goals of the present study were thus to identify the clinical and biological risk factors for alcohol-related neuropsychological impairments and to determine the threshold beyond which these risk factors can be considered significant. Thirty alcoholic patients and 15 healthy controls had a blood test and underwent a neuropsychological examination. Alcohol severity measures, and liver, thiamine and malnutrition variables, were included in logistic regression models to determine the risk factors for cognitive and motor impairments (executive functions, visuospatial abilities, verbal episodic memory, ataxia), as well as those related to the severity of patients' overall neuropsychological profile (moderate or severe impairments). Liver fibrosis was found to be a risk factor for executive impairments and also for ataxia, when it was associated with long-term alcohol misuse and symptoms of withdrawal. Altered thiamine metabolism was solely predictive of verbal episodic memory impairments. This combination of biological abnormalities was associated with a profile of moderate neuropsychological impairments. Malnutrition was associated with a profile of more severe impairments. Malnutrition, altered liver function and thiamine metabolism explain, at least partially, the heterogeneity of alcohol-related neuropsychological impairments. Our findings could allow clinicians to identify patients at particular risk of severe neuropsychological impairments before the onset of irreversible and debilitating neurological complications. PMID:27617840

  11. A systems biology approach to transcription factor binding site prediction.

    Directory of Open Access Journals (Sweden)

    Xiang Zhou

    Full Text Available BACKGROUND: The elucidation of mammalian transcriptional regulatory networks holds great promise for both basic and translational research and remains one the greatest challenges to systems biology. Recent reverse engineering methods deduce regulatory interactions from large-scale mRNA expression profiles and cross-species conserved regulatory regions in DNA. Technical challenges faced by these methods include distinguishing between direct and indirect interactions, associating transcription regulators with predicted transcription factor binding sites (TFBSs, identifying non-linearly conserved binding sites across species, and providing realistic accuracy estimates. METHODOLOGY/PRINCIPAL FINDINGS: We address these challenges by closely integrating proven methods for regulatory network reverse engineering from mRNA expression data, linearly and non-linearly conserved regulatory region discovery, and TFBS evaluation and discovery. Using an extensive test set of high-likelihood interactions, which we collected in order to provide realistic prediction-accuracy estimates, we show that a careful integration of these methods leads to significant improvements in prediction accuracy. To verify our methods, we biochemically validated TFBS predictions made for both transcription factors (TFs and co-factors; we validated binding site predictions made using a known E2F1 DNA-binding motif on E2F1 predicted promoter targets, known E2F1 and JUND motifs on JUND predicted promoter targets, and a de novo discovered motif for BCL6 on BCL6 predicted promoter targets. Finally, to demonstrate accuracy of prediction using an external dataset, we showed that sites matching predicted motifs for ZNF263 are significantly enriched in recent ZNF263 ChIP-seq data. CONCLUSIONS/SIGNIFICANCE: Using an integrative framework, we were able to address technical challenges faced by state of the art network reverse engineering methods, leading to significant improvement in direct

  12. Resilience of caregivers of people with dementia: a systematic review of biological and psychosocial determinants

    Directory of Open Access Journals (Sweden)

    Rachel Dias

    2015-03-01

    Full Text Available Introduction: Although caregivers of people with dementia may face difficulties, some positive feelings of caregiving may be associated with resilience.Objective: This study systematically reviewed the definitions, methodological approaches and determinant models associated with resilience among caregivers of people with dementia.Methods: Search for articles published between 2003 and 2014 in ISI, PubMed/MEDLINE, SciELO and Lilacs using the search terms resilience, caregivers and dementia.Results and conclusions: Resilience has been defined as positive adaptation to face adversity, flexibility, psychological well-being, strength, healthy life, burden, social network and satisfaction with social support. No consensus was found about the definition of resilience associated with dementia. We classified the determinant variables into biological, psychological and social models. Higher levels of resilience were associated with lower depression rates and greater physical health. Other biological factors associated with higher levels of resilience were older age, African-American ethnicity and female sex. Lower burden, stress, neuroticism and perceived control were the main psychological factors associated with resilience. Social support was a moderating factor of resilience, and different types of support seemed to relieve the physical and mental overload caused by stress.

  13. Car Sales: Investigation into Factors Determining Consumer Behavior

    OpenAIRE

    Aurelija Samoškienė

    2011-01-01

    The article examines customer behaviour in general and discusses factors determining customer behaviour in car industry. The paper describes a concept of consumer behaviour and the importance of factors influencing the situation. Empirical study about factors determining car industry in consumer-made decisions is carried out. In addition, statistical factor analysis is performed. The key sets of factors helping the user with choosing a new car are iden­tified and analysed at the level of the ...

  14. Determinant factors of Yemeni maxillary arch dimensions

    Directory of Open Access Journals (Sweden)

    Nabil Muhsen Al-Zubair

    2015-01-01

    Conclusion: Measurements of palatal depth and relationships of the canines to one another and to other teeth thus had the widest ranges, implying that these dimensions are the strongest determinants of maxillary arch size.

  15. Determinants of Risk Factors for Asthma

    Directory of Open Access Journals (Sweden)

    William W Busse

    1999-01-01

    Full Text Available There are a number of risk factors for the development of asthma, including genetic and environmental components. Moreover, there is mounting evidence that a variety of genes are associated with the features of asthma, such as persistent wheezing, airway responsiveness and chronic bronchial inflammation. However, for expression of these features, other factors must also come into play. This paper focuses on the importance of environmental factors in the development of asthma, including allergens and respiratory infections. From current evidence, it appears that in subjects with the appropriate genetic make-up, infections and allergens induce a proinflammatory cytokine response that causes airway inflammation and that in turn leads to the initiation and persistence of altered airway function.

  16. PROGNOSTIC FACTORS DETERMINING MORTALITY IN SURGICAL NEONATES

    Directory of Open Access Journals (Sweden)

    Vivek Manchanda

    2012-01-01

    Full Text Available Background: To assess the prognosis of surgical neonates at admission and the factors responsible for mortality in neonates.Material and Methods: A prospective study was conducted in a tertiary level hospital over 15 months and various clinical and biochemical parameters were collected and analyzed using STATA® and SPSS®.Results: On multivariate analysis of 165 neonates, early gestational age, respiratory distress and shock at presentation were the factors of poor prognosis in neonates. The factors could be related to poor antenatal care and sepsis acquired before transfer of the baby to the nursery. Conclusion: The improvement in antenatal care and asepsis during transfer and handling the babies is of utmost importance to improve the prognosis of surgical neonates.

  17. Determinant factors of gender identity: a commentary.

    Science.gov (United States)

    Liao, Lih-Mei; Audi, Laura; Magritte, Ellie; Meyer-Bahlburg, Heino F L; Quigley, Charmian A

    2012-12-01

    Paediatric specialists involved in the care of children with disorders of sex development may be expected to provide straightforward answers to questions concerning the "true sex" of a child, reflecting common perceptions of sex/gender as an immutable binary biological reality. This article highlights how much more broad and complex the topic of gender identity and its development is. Many theories have been put forward to advance knowledge of gender identity. Against the breadth and depth of this vast topic, the current overview is inevitably incomplete. It begins by arguing for a more consistent use of 'sex' and 'gender'. It considers in turn three influential theoretical frameworks that lend themselves to empirical research. These are: 1) the role of the brain; 2) the role of socialisation; and 3) multi-dimensional gender development. The article ends by suggesting potentially fruitful questions and areas for future research.

  18. Psychological factors determine depressive symptomatology after stroke

    NARCIS (Netherlands)

    Van Mierlo, Maria L.; Van Heugten, Caroline M.; Post, Marcel W.; De Kort, Paul L.; Visser-Meily, Anne

    2015-01-01

    Objective To identify psychological factors related to poststroke depressive symptoms. Design Cross-sectional study, with patients assessed at 2 months poststroke. Setting Patients with stroke from 6 general hospitals. Participants Stroke patients (N=344; mean age ± SD, 66.9±12.3y). Interventions No

  19. T-box factors determine cardiac design.

    Science.gov (United States)

    Hoogaars, W M H; Barnett, P; Moorman, A F M; Christoffels, V M

    2007-03-01

    The heart of higher vertebrates is a structurally complicated multi-chambered pump that contracts synchronously. For its proper function a number of distinct integrated components have to be generated, including force-generating compartments, unidirectional valves, septa and a system in charge of the initiation and coordinated propagation of the depolarizing impulse over the heart. Not surprisingly, a large number of regulating factors are involved in these processes that act in complex and intertwined pathways to regulate the activity of target genes responsible for morphogenesis and function. The finding that mutations in T-box transcription factor-encoding genes in humans lead to congenital heart defects has focused attention on the importance of this family of regulators in heart development. Functional and genetic analyses in a variety of divergent species has demonstrated the critical roles of multiple T-box factor gene family members, including Tbx11, -2, -3, -5, -18 and -20, in the patterning, recruitment, specification, differentiation and growth processes underlying formation and integration of the heart components. Insight into the roles of T-box factors in these processes will enhance our understanding of heart formation and the underlying molecular regulatory pathways. PMID:17380306

  20. Depth Determination of an Abnormal Heat Source in Biological Tissues

    Institute of Scientific and Technical Information of China (English)

    WANG Qing-Hua; LI Zhen-Hua; LAI Jian-Cheng; HE An-Zhi

    2011-01-01

    We deduce the surface temperature distribution generated by the inner point heat source in biological tissues and propose a graphic method to retrieve the depth of the point heat source. The practical surface temperature distribution can be regarded as the convolution of the temperature distribution of the inner point heat source with the heat source shape function. The depth of an abnormal heat source in biological tissues can be retrieved by using the graphic method combined with the blind deconvolution scheme.%We deduce the surface temperature distribution generated by the inner point heat source in biological tissues and propose a graphic method to retrieve the depth of the point heat source.The practical surface temperature distribution can be regarded as the convolution of the temperature distribution of the inner point heat source with the heat source shape function.The depth of an abnormal heat source in biological tissues can be retrieved by using the graphic method combined with the blind deconvolution scheme.Surface temperature distribution of the biological tissues is closely related to the neighboring metabolic heat production,blood circulation in an organism and environmental temperature.[1] The abnormal metabolic performances of a local region in biological tissue imply malignant changes occurring,which can be distinguished from the variance of surface temperature.Modern development of thermal infrared (TIR) imaging has made the surface temperature measurement of biological tissue easier.Nowadays,several types of tumors,e.g.skin or breast can be recognized with TIR imaging.[2] The diagnostics with TIR imaging require more experienced operators and can not accurately ascertain the site of pathological changes,which limits the value of this technology.Therefore ascertaining the depth of inner heat source in biological body has the extremely important clinical value.

  1. 25 CFR 153.4 - Factors determining competency.

    Science.gov (United States)

    2010-04-01

    ... 25 Indians 1 2010-04-01 2010-04-01 false Factors determining competency. 153.4 Section 153.4 Indians BUREAU OF INDIAN AFFAIRS, DEPARTMENT OF THE INTERIOR LAND AND WATER DETERMINATION OF COMPETENCY: CROW INDIANS § 153.4 Factors determining competency. Among the matters to be considered by...

  2. Estimating Escherichia coli loads in streams based on various physical, chemical, and biological factors.

    Science.gov (United States)

    Dwivedi, Dipankar; Mohanty, Binayak P; Lesikar, Bruce J

    2013-05-01

    Microbes have been identified as a major contaminant of water resources. Escherichia coli (E. coli) is a commonly used indicator organism. It is well recognized that the fate of E. coli in surface water systems is governed by multiple physical, chemical, and biological factors. The aim of this work is to provide insight into the physical, chemical, and biological factors along with their interactions that are critical in the estimation of E. coli loads in surface streams. There are various models to predict E. coli loads in streams, but they tend to be system or site specific or overly complex without enhancing our understanding of these factors. Hence, based on available data, a Bayesian Neural Network (BNN) is presented for estimating E. coli loads based on physical, chemical, and biological factors in streams. The BNN has the dual advantage of overcoming the absence of quality data (with regards to consistency in data) and determination of mechanistic model parameters by employing a probabilistic framework. This study evaluates whether the BNN model can be an effective alternative tool to mechanistic models for E. coli loads estimation in streams. For this purpose, a comparison with a traditional model (LOADEST, USGS) is conducted. The models are compared for estimated E. coli loads based on available water quality data in Plum Creek, Texas. All the model efficiency measures suggest that overall E. coli loads estimations by the BNN model are better than the E. coli loads estimations by the LOADEST model on all the three occasions (three-fold cross validation). Thirteen factors were used for estimating E. coli loads with the exhaustive feature selection technique, which indicated that six of thirteen factors are important for estimating E. coli loads. Physical factors included temperature and dissolved oxygen; chemical factors include phosphate and ammonia; biological factors include suspended solids and chlorophyll. The results highlight that the LOADEST model

  3. Factors determining the economic value of groundwater

    Science.gov (United States)

    Qureshi, M. Ejaz; Reeson, Andrew; Reinelt, Peter; Brozović, Nicholas; Whitten, Stuart

    2012-08-01

    Increasing groundwater extraction threatens aquifer sustainability for future generations. Making the best use of limited groundwater resources requires knowledge of its alternative extractive and non-extractive values, as well as the cost of extraction and the hydrological interlinkages between alternative uses. Groundwater value is driven by a number of factors including its supply and demand and institutional and policy factors. These factors and how they affect value of groundwater are described. Also described are the various components relevant to the economic valuation of groundwater and there is discussion on the potential difficulties in their practical estimation. It is argued that groundwater management is essential when there are large potential spatial and temporal externalities related to groundwater pumping. Maintaining non-extractive and option values is likely to require trade-offs with current extractive uses. Well-informed management will be required to allocate groundwater efficiently between different users such as agriculture, industry and the environment, while also balancing the needs of current and future generations.

  4. Biology of sexuality inborn determinants of human sexual response.

    Science.gov (United States)

    Goodman, R E

    1983-09-01

    Opinions vary on the relative importance of biological and learning processes in the aetiology of sexual expression and deviance. The structure of personality, consistency of fantasy patterns, and the familial nature of homosexuality hint at a biological anlage. Research with the HY-antigen complex and X chromosome, and the elucidation of the interactions of intrauterine testosterone and its products with the foetal brain and neurotransmitters, have given us new models to understand the programming of sexuality. However, gonadotrophin feedback is not relevant as an indicator of brain feminization in primates and man. Finally, the interaction of masculinization and defeminization provides us with a model for understanding homosexual behaviour. PMID:6138111

  5. Factors determining antibody distribution in tumors

    Science.gov (United States)

    Thurber, Greg M.; Schmidt, Michael M.; Wittrup, K. Dane

    2009-01-01

    The development of antibody therapies for cancer is increasing rapidly, primarily owing to their specificity. Antibody distribution in tumors is often extremely uneven, however, leading to some malignant cells being exposed to saturating concentrations of antibody, whereas others are completely untargeted. This is detrimental because large regions of cells escape therapy, whereas other regions might be exposed to suboptimal concentrations that promote a selection of resistant mutants. The distribution of antibody depends on a variety of factors, including dose, affinity, antigens per cell and molecular size. Because these parameters are often known or easily estimated, a quick calculation based on simple modeling considerations can predict the uniformity of targeting within a tumor. Such analyses should enable experimental researchers to identify in a straightforward way the limitations in achieving evenly distributed antibody, and design and test improved antibody therapeutics more rationally. PMID:18179828

  6. Factors Determining Foreign Direct Investments in Albania

    Directory of Open Access Journals (Sweden)

    EVIS GJEBREA

    2013-06-01

    Full Text Available The foreign direct investments (FDIs have taken a very great extent in the last decades in both developing and developed countries, having a positive impact on economic growth. This is mainly due to trade liberalization, as well as other advantages such as higher returns on investments, potential resource seeking, new market seeking, or cheap labor force. In developing countries investors face many risks that go beyond market risks such as corruption, unsustainable legal system, lack of proper definition of property rights, or high bureaucratic rules for businesses.The aim of this paper is to analyze the behavior of Foreign Direct Investments in Albania compared to other countries in the Western Balkans. The study focuses on the trend of Inward and Outward FDIs in Albania and the region for the period 1992-2011, as well as an analysis of the factors influencing FDI flows. The main result is that Albania stands on a very good position regarding FDI flows compared to other countries. This is mainly due to massive privatizations taken after the fall of communism and due to efforts by the Government for creating a business friendly environment.

  7. Factors Determining Nestedness in Complex Networks

    Science.gov (United States)

    Jonhson, Samuel; Domínguez-García, Virginia; Muñoz, Miguel A.

    2013-01-01

    Understanding the causes and effects of network structural features is a key task in deciphering complex systems. In this context, the property of network nestedness has aroused a fair amount of interest as regards ecological networks. Indeed, Bastolla et al. introduced a simple measure of network nestedness which opened the door to analytical understanding, allowing them to conclude that biodiversity is strongly enhanced in highly nested mutualistic networks. Here, we suggest a slightly refined version of such a measure of nestedness and study how it is influenced by the most basic structural properties of networks, such as degree distribution and degree-degree correlations (i.e. assortativity). We find that most of the empirically found nestedness stems from heterogeneity in the degree distribution. Once such an influence has been discounted – as a second factor – we find that nestedness is strongly correlated with disassortativity and hence – as random networks have been recently found to be naturally disassortative – they also tend to be naturally nested just as the result of chance. PMID:24069264

  8. Cardiovascular risk factors in high-need psoriasis patients and its implications for biological therapies.

    NARCIS (Netherlands)

    Driessen, R.J.B.; Boezeman, J.B.M.; Kerkhof, P.C.M. van de; Jong, E.M.G.J. de

    2009-01-01

    BACKGROUND: The associations between psoriasis and cardiovascular risk factors are reported to be stronger as psoriasis severity increases. This makes studying cardiovascular risk factors in high-need psoriasis patients, eligible for biological therapy, interesting. OBJECTIVE: To survey the prevalen

  9. Skin Cancer: Biology, Risk Factors & Treatment | NIH MedlinePlus the Magazine

    Science.gov (United States)

    ... of this page please turn Javascript on. Feature: Skin Cancer Skin Cancer: Biology, Risk Factors & Treatment Past Issues / Summer 2013 ... Factors When you're told that you have skin cancer, it's natural to wonder what may have caused ...

  10. Biological risk factors in informal recyclers of Medellin city, 2005

    Directory of Open Access Journals (Sweden)

    Viviana L. Ballesteros

    2008-06-01

    Full Text Available The informal recyclers constitute a vulnerable population to problems of health by their constant exhibition to biological, chemical, physical and social risks, without protection. Objective: this work identify the biological risk facts to which the informal recyclers of the Bazaar of the Bridges of Medellin city. Methods: it was performed a Cross-sectional study. The sample was no probabilistic with 88 recyclers and the analysis unit was the informal recycler. It was applied a survey, a guide of observation of the activity of the recycler and were studied variables of person, place, time, type of biological risk facts, frequency of exhibition, felt morbidity and measures of protection. The analysis was statistical descriptive. Results: it was identified biological risk facts related to the contact with material in decomposition (96.6%, contaminated material (96.6%, animals (62.5% and arthropoda (79.5%. The se The se--curity measures to protect them from biological risk facts are used in less than 52% of recyclers; in addition, only 13.6% of the population were vaccinated, which increases the probability of becoming ill in this population. Conclusions: that the informal recyclers are exposed to different biological risk facts with little prevention, causing that population be vulnerable for the acquisition of infectious diseases.

  11. Identification of Bacteria and Determination of Biological Indicators

    Science.gov (United States)

    Venkateswaran, Kasthuri; La Duc, Myron T.; Vaishampayan, Parag A.

    2009-01-01

    The ultimate goal of planetary protection research is to develop superior strategies for inactivating resistance bearing micro-organisms like Rummeli - bacillus stabekisii. By first identifying the particular physiologic pathway and/or structural component of the cell/spore that affords it such elevated tolerance, eradication regimes can then be designed to target these resistance-conferring moieties without jeopardizing the structural integrity of spacecraft hardware. Furthermore, hospitals and government agencies frequently use biological indicators to ensure the efficacy of a wide range of sterilization processes. The spores of Rummelibacillus stabekisii, which are far more resistant to many of such perturbations, could likely serve as a more significant biological indicator for potential survival than those being used currently.

  12. Biological factors underlying sex differences in neurological disorders.

    Science.gov (United States)

    Loke, Hannah; Harley, Vincent; Lee, Joohyung

    2015-08-01

    The prevalence, age of onset, pathophysiology, and symptomatology of many neurological and neuropsychiatric conditions differ significantly between males and females. Females suffer more from mood disorders such as depression and anxiety, whereas males are more susceptible to deficits in the dopamine system including Parkinson's disease (PD), attention-deficit hyperactivity disorder (ADHD), schizophrenia, and autism spectrum disorders (ASD). Until recently, these sex differences have been explained solely by the neuroprotective actions of sex hormones in females. Emerging evidence however indicates that the sex chromosome genes (i.e. X- and Y-linked genes) also contribute to brain sex differences. In particular, the Y-chromosome gene, SRY (Sex-determining Region on the Y chromosome) is an interesting candidate as it is expressed in dopamine-abundant brain regions, where it regulates dopamine biosynthesis and dopamine-mediated functions such as voluntary movement in males. Furthermore, SRY expression is dysregulated in a toxin-induced model of PD, suggesting a role for SRY in the pathogenesis of dopamine cells. Taken together, these studies highlight the importance of understanding the interplay between sex-specific hormones and sex-specific genes in healthy and diseased brain. In particular, better understanding of regulation and function of SRY in the male brain could provide entirely novel and important insights into genetic factors involved in the susceptibility of men to neurological disorders, as well as development of novel sex-specific therapies. PMID:26028290

  13. Fatores determinantes do crescimento infantil Determinant factors of infant growth

    Directory of Open Access Journals (Sweden)

    Sylvia de Azevedo Mello Romani

    2004-03-01

    Full Text Available Esta revisão enfoca os fatores que interferem no crescimento de crianças nos primeiros anos de vida. Foram utilizadas informações de artigos publicados em revistas científicas, teses e publicações de organizações internacionais. O crescimento infantil se constitui em um dos melhores indicadores de saúde da criança e o retardo estatural representa atualmente, a característica antropométrica mais representativa do quadro epidemiológico da desnutrição no Brasil. Ressaltando a importância do fator genético no crescimento, a revisão abrange com maior ênfase a atuação dos fatores extrínsecos, sabendo-se que o processo de crescimento resulta da interação entre a carga genética e os fatores do meio ambiente, os quais premitirão a maior ou menor expressão do potencial genético. Face a comprovada natureza multicausal do crescimento infantil, vários estudos têm sido desenvolvidos, buscando relacionar variáveis biológicas, socioeconômicas, maternas, ambientais, culturais, demográficas, nutricionais, entre outras, com a sua etiologia, seu desenvolvimento e sua manutenção. A revisão apresentada reforça o interesse em investigações sobre o crescimento na primeira infância que devem ser permanentes, devido, principalmente, às repercussões a longo prazo sobre a saúde infantil.This review focuses on factors interfering with growth during the first years of life. Information was collected from articles published in indexed scientific journals, theses, technical books and publications of international organizations. Infant growth is one of the best health indicators, and linear growth retardation is currently the most representative anthropometric characteristic of child nutrition epidemiology in Brazil. The review indicates the value of genetics in growth, focusing, however on the influence of the extrinsic factors. Growth process results from interaction between genetic and environmental factors, determining variation

  14. Mediating factors of land use change among coffee farmers in a biological corridor

    DEFF Research Database (Denmark)

    Bosselmann, Aske Skovmand

    2012-01-01

    Trees in agricultural landscapes are important for the provision of environmental services. This study assesses the loss of shade coffee during a 9 year period in a biological corridor in Costa Rica, and investigates the mediating factors of land use change. Following a conceptual framework...... that presents how household and farm characteristics mediate the interplay between underlying and proximate causes of land use change, the effect of the mediating factors is determined by applying an ordered probit model to household and land use data for 2000 and 2009 from 217 former and present coffee farmers....... Additional 224 telephone interviews supplement the data on land use change. Results show a 50% reduction in the coffee area and a corresponding loss of trees. Family labor, age of household head, coffee prices, and use of shade tree products significantly reduce the probability of converting the coffee field...

  15. Compressed Sensing Electron Tomography for Determining Biological Structure

    Science.gov (United States)

    Guay, Matthew D.; Czaja, Wojciech; Aronova, Maria A.; Leapman, Richard D.

    2016-06-01

    There has been growing interest in applying compressed sensing (CS) theory and practice to reconstruct 3D volumes at the nanoscale from electron tomography datasets of inorganic materials, based on known sparsity in the structure of interest. Here we explore the application of CS for visualizing the 3D structure of biological specimens from tomographic tilt series acquired in the scanning transmission electron microscope (STEM). CS-ET reconstructions match or outperform commonly used alternative methods in full and undersampled tomogram recovery, but with less significant performance gains than observed for the imaging of inorganic materials. We propose that this disparity stems from the increased structural complexity of biological systems, as supported by theoretical CS sampling considerations and numerical results in simulated phantom datasets. A detailed analysis of the efficacy of CS-ET for undersampled recovery is therefore complicated by the structure of the object being imaged. The numerical nonlinear decoding process of CS shares strong connections with popular regularized least-squares methods, and the use of such numerical recovery techniques for mitigating artifacts and denoising in reconstructions of fully sampled datasets remains advantageous. This article provides a link to the software that has been developed for CS-ET reconstruction of electron tomographic data sets.

  16. Influence of biological and ecological factors on the radio-sensitivity of laboratory animals

    International Nuclear Information System (INIS)

    The biological and ecological factors liable to induce a change in the radio-sensitivity of a species are undoubtedly responsible for the large fluctuations observed during radio-biological experiments. It is easy to limit or to suppress the effects of some of them (genetic or nutritional factors). Since the research worker cannot control the others it is necessary to take them into account. In this report the authors analyse the action of two factors chosen as examples: - the first concerns biological rhythms; - the second attempts to define the role of health conditions. Other factors will be dealt with in a later report. (authors)

  17. Biological stability of drinking water: Controlling factors, methods, and challenges

    NARCIS (Netherlands)

    Prest, E.I.E.D.; Hammes, F.; Van Loosdrecht, M.C.M.; Vrouwenvelder, J.S.

    2016-01-01

    Biological stability of drinking water refers to the concept of providing consumers with drinking water of same microbial quality at the tap as produced at the water treatment facility. However, uncontrolled growth of bacteria can occur during distribution in water mains and premise plumbing, and ca

  18. Physical-chemical determinant properties of biological communities in continental semi-arid waters.

    Science.gov (United States)

    da Rocha, Francisco Cleiton; de Andrade, Eunice Maia; Lopes, Fernando Bezerra; de Paula Filho, Francisco José; Filho, José Hamilton Costa; da Silva, Merivalda Doroteu

    2016-08-01

    Throughout human history, water has undergone changes in quality. This problem is more serious in dry areas, where there is a natural water deficit due to climatic factors. The aims of this study, therefore, were (i) to verify correlations between physical attributes, chemical attributes and biological metrics and (ii) from the biological attributes, to verify the similarity between different points of a body of water in a tropical semi-arid region. Samples were collected every 2 months, from July 2009 to July 2011, at seven points. Four physical attributes, five chemical attributes and four biological metrics were investigated. To identify the correlations between the physicochemical properties and the biological metrics, hierarchical cluster analysis (HCA) and canonical correlation analysis (CCA) were applied. Nine classes of phytoplankton were identified, with the predominance of species of cyanobacteria, and ten families of macroinvertebrates. The use of HCA resulted in the formation of three similar groups, showing that it was possible to reduce the number of sampling points when monitoring water quality with a consequent reduction in cost. Group I was formed from the waters at the high end of the reservoir (points P1, P2 and P3), group II by the waters from the middle third (points P4 and P5), and group III by the waters from the lower part of the reservoir (points P6 and P7). Richness of the phytoplanktons Cyanophyceae, Chorophyceae and Bacillariophyceae was the attribute which determined dissimilarity in water quality. Using CCA, it was possible to identify the spatial variability of the physicochemical attributes (TSS, TKN, nitrate and total phosphorus) that most influence the metrics of the macroinvertebrates and phytoplankton present in the water. Low macroinvertebrate diversity, with a predominance of indicator families for deterioration in water quality, and the composition of phytoplankton showing a predominance of cyanobacteria, suggests greater

  19. Physical-chemical determinant properties of biological communities in continental semi-arid waters.

    Science.gov (United States)

    da Rocha, Francisco Cleiton; de Andrade, Eunice Maia; Lopes, Fernando Bezerra; de Paula Filho, Francisco José; Filho, José Hamilton Costa; da Silva, Merivalda Doroteu

    2016-08-01

    Throughout human history, water has undergone changes in quality. This problem is more serious in dry areas, where there is a natural water deficit due to climatic factors. The aims of this study, therefore, were (i) to verify correlations between physical attributes, chemical attributes and biological metrics and (ii) from the biological attributes, to verify the similarity between different points of a body of water in a tropical semi-arid region. Samples were collected every 2 months, from July 2009 to July 2011, at seven points. Four physical attributes, five chemical attributes and four biological metrics were investigated. To identify the correlations between the physicochemical properties and the biological metrics, hierarchical cluster analysis (HCA) and canonical correlation analysis (CCA) were applied. Nine classes of phytoplankton were identified, with the predominance of species of cyanobacteria, and ten families of macroinvertebrates. The use of HCA resulted in the formation of three similar groups, showing that it was possible to reduce the number of sampling points when monitoring water quality with a consequent reduction in cost. Group I was formed from the waters at the high end of the reservoir (points P1, P2 and P3), group II by the waters from the middle third (points P4 and P5), and group III by the waters from the lower part of the reservoir (points P6 and P7). Richness of the phytoplanktons Cyanophyceae, Chorophyceae and Bacillariophyceae was the attribute which determined dissimilarity in water quality. Using CCA, it was possible to identify the spatial variability of the physicochemical attributes (TSS, TKN, nitrate and total phosphorus) that most influence the metrics of the macroinvertebrates and phytoplankton present in the water. Low macroinvertebrate diversity, with a predominance of indicator families for deterioration in water quality, and the composition of phytoplankton showing a predominance of cyanobacteria, suggests greater

  20. Nonoxidized, biologically active parathyroid hormone determines mortality in hemodialysis patients

    DEFF Research Database (Denmark)

    Tepel, Martin; Armbruster, Franz Paul; Grön, Hans Jürgen;

    2013-01-01

    Background: It was shown that nonoxidized PTH (n-oxPTH) is bioactive, whereas the oxidation of PTH results in a loss of biological activity. Methods: In this study we analyzed the association of n-oxPTH on mortality in hemodialysis patients using a recently developed assay system. Results......: Hemodialysis patients (224 men, 116 women) had a median age of 66 years. One hundred seventy patients (50%) died during the follow-up period of 5 years. Median n-oxPTH levels were higher in survivors (7.2 ng/L) compared with deceased patients (5.0 ng/L; P = .002). Survival analysis showed an increased survival....... Conclusions: The predictive power of n-oxPTH and iPTH on the mortality of hemodialysis patients differs substantially. Measurements of n-oxPTH may reflect the hormone status more precisely. The iPTH-associated mortality is most likely describing oxidative stress-related mortality....

  1. Mass spectrometric determination of early and advanced glycation in biology.

    Science.gov (United States)

    Rabbani, Naila; Ashour, Amal; Thornalley, Paul J

    2016-08-01

    Protein glycation in biological systems occurs predominantly on lysine, arginine and N-terminal residues of proteins. Major quantitative glycation adducts are found at mean extents of modification of 1-5 mol percent of proteins. These are glucose-derived fructosamine on lysine and N-terminal residues of proteins, methylglyoxal-derived hydroimidazolone on arginine residues and N(ε)-carboxymethyl-lysine residues mainly formed by the oxidative degradation of fructosamine. Total glycation adducts of different types are quantified by stable isotopic dilution analysis liquid chromatography-tandem mass spectrometry (LC-MS/MS) in multiple reaction monitoring mode. Metabolism of glycated proteins is followed by LC-MS/MS of glycation free adducts as minor components of the amino acid metabolome. Glycated proteins and sites of modification within them - amino acid residues modified by the glycating agent moiety - are identified and quantified by label-free and stable isotope labelling with amino acids in cell culture (SILAC) high resolution mass spectrometry. Sites of glycation by glucose and methylglyoxal in selected proteins are listed. Key issues in applying proteomics techniques to analysis of glycated proteins are: (i) avoiding compromise of analysis by formation, loss and relocation of glycation adducts in pre-analytic processing; (ii) specificity of immunoaffinity enrichment procedures, (iii) maximizing protein sequence coverage in mass spectrometric analysis for detection of glycation sites, and (iv) development of bioinformatics tools for prediction of protein glycation sites. Protein glycation studies have important applications in biology, ageing and translational medicine - particularly on studies of obesity, diabetes, cardiovascular disease, renal failure, neurological disorders and cancer. Mass spectrometric analysis of glycated proteins has yet to find widespread use clinically. Future use in health screening, disease diagnosis and therapeutic monitoring, and

  2. Developmental biology of sex determination : establishing a basis for systems approach

    OpenAIRE

    Segerståhl, Margareta

    2008-01-01

    The existence of males and females is a fundamental aspect of animal biology but the developmental mechanisms of sex determination and sexual differentiation exhibit surprising evolutionary diversity. Depending on the species, sex determination mechanisms range from genetic sex chromosome effects to environmental temperature effects and even to social cues that derive from local population structure. Many genes and molecules that play a role in sex determination biology have been identified, ...

  3. Thorium determination in water and biological materials by fission track

    International Nuclear Information System (INIS)

    As a segment of a research programme on the study of bioaccumulation of radionuclides, in animals and vegetables from Morro do Ferro, Pocos de Caldas, MG, a fission track method for the determination of low levels of thorium in environmental samples was developed as an alternative for alpha spectroscopy. The study was carried out in early alpha spectroscopy samples, containing high levels of 228 Th activity, which makes difficult the 232 Th determination. A dry way method for thorium evaluation was developed. Pieces of membrane filters, containing La F3 (Th), coupled to Makrofol detectors, were irradiated in the core of a research reactor, IEA-R1 (IPEN). (author)

  4. Energy and time determine scaling in biological and computer designs.

    Science.gov (United States)

    Moses, Melanie; Bezerra, George; Edwards, Benjamin; Brown, James; Forrest, Stephanie

    2016-08-19

    Metabolic rate in animals and power consumption in computers are analogous quantities that scale similarly with size. We analyse vascular systems of mammals and on-chip networks of microprocessors, where natural selection and human engineering, respectively, have produced systems that minimize both energy dissipation and delivery times. Using a simple network model that simultaneously minimizes energy and time, our analysis explains empirically observed trends in the scaling of metabolic rate in mammals and power consumption and performance in microprocessors across several orders of magnitude in size. Just as the evolutionary transitions from unicellular to multicellular animals in biology are associated with shifts in metabolic scaling, our model suggests that the scaling of power and performance will change as computer designs transition to decentralized multi-core and distributed cyber-physical systems. More generally, a single energy-time minimization principle may govern the design of many complex systems that process energy, materials and information.This article is part of the themed issue 'The major synthetic evolutionary transitions'. PMID:27431524

  5. Logical Reduction of Biological Networks to Their Most Determinative Components.

    Science.gov (United States)

    Matache, Mihaela T; Matache, Valentin

    2016-07-01

    Boolean networks have been widely used as models for gene regulatory networks, signal transduction networks, or neural networks, among many others. One of the main difficulties in analyzing the dynamics of a Boolean network and its sensitivity to perturbations or mutations is the fact that it grows exponentially with the number of nodes. Therefore, various approaches for simplifying the computations and reducing the network to a subset of relevant nodes have been proposed in the past few years. We consider a recently introduced method for reducing a Boolean network to its most determinative nodes that yield the highest information gain. The determinative power of a node is obtained by a summation of all mutual information quantities over all nodes having the chosen node as a common input, thus representing a measure of information gain obtained by the knowledge of the node under consideration. The determinative power of nodes has been considered in the literature under the assumption that the inputs are independent in which case one can use the Bahadur orthonormal basis. In this article, we relax that assumption and use a standard orthonormal basis instead. We use techniques of Hilbert space operators and harmonic analysis to generate formulas for the sensitivity to perturbations of nodes, quantified by the notions of influence, average sensitivity, and strength. Since we work on finite-dimensional spaces, our formulas and estimates can be and are formulated in plain matrix algebra terminology. We analyze the determinative power of nodes for a Boolean model of a signal transduction network of a generic fibroblast cell. We also show the similarities and differences induced by the alternative complete orthonormal basis used. Among the similarities, we mention the fact that the knowledge of the states of the most determinative nodes reduces the entropy or uncertainty of the overall network significantly. In a special case, we obtain a stronger result than in previous

  6. Précis of "Lifelines: biology, freedom, determinism".

    Science.gov (United States)

    Rose, S

    1999-10-01

    There are many ways of describing and explaining the properties of living systems; causal, functional, and reductive accounts are necessary but no one account has primacy. The history of biology as a discipline has given excessive authority to reductionism, which collapses higher level accounts, such as social or behavioural ones, into molecular ones. Such reductionism becomes crudely ideological when applied to the human condition, with its claims for genes "for" everything from sexual orientation to compulsive shopping. The current enthusiasm for genetics and ultra-Darwinist accounts, with their selfish-gene metaphors for living processes, misunderstand both the phenomena of development and the interactive role that DNA and the fluid genome play in the cellular orchestra. DNA is not a blueprint, and the four dimensions of life (three of space, one of time) cannot be read off from its one-dimensional strand. Both developmental and evolutionary processes are more than merely instructive or selective; the organism constructs itself, a process known as autopoiesis, through a lifeline trajectory. Because organisms are thermodynamically open systems, living processes are homeodynamic, not homeostatic. The self-organising membrane-bound and energy-utilising metabolic web of the cell must have evolved prior to socalled naked replicators. Evolution is constrained by physics, chemistry, and structure; not all change is powered by natural selection, and not all phenotypes are adaptive. Finally, therefore, living processes are radically indeterminate; like all other living organisms, but to an even greater degree, we make our own future, though in circumstances not of our own choosing. PMID:11301572

  7. Classifying transcription factor targets and discovering relevant biological features

    OpenAIRE

    DeLisi Charles; Kon Mark; Holloway Dustin T

    2008-01-01

    Abstract Background An important goal in post-genomic research is discovering the network of interactions between transcription factors (TFs) and the genes they regulate. We have previously reported the development of a supervised-learning approach to TF target identification, and used it to predict targets of 104 transcription factors in yeast. We now include a new sequence conservation measure, expand our predictions to include 59 new TFs, introduce a web-server, and implement an improved r...

  8. Chemical and biological factors affecting bioavailability of contaminants in seawater

    International Nuclear Information System (INIS)

    This paper discusses the influence that salinity has on the bioavailability of the two largest classes of contaminants, trace metals and organic compounds will be discussed. Although data on contaminant toxicity will be used to draw inferences about chemical availability, this discussion will focus on the properties that contaminants are likely to exhibit in waters of varying salinities. In addition, information on physiological changes that are affected by salinity will be used to illustrate how biological effects can alter the apparent availability of contaminants

  9. Determination of Alkali Ions in Biological and Environmental Samples.

    Science.gov (United States)

    Hauser, Peter C

    2016-01-01

    An overview of the common methods for the determination of the alkali metals is given. These are drawn from all of the three principle branches of quantitative analysis and consist mainly of optical atomic spectrometric methods, ion-selective electrodes, and the separation methods of ion-chromatography and capillary electrophoresis. Their main characteristics and performance parameters are discussed. Important specific applications are also examined, namely clinical analysis, single cell analysis, the analysis of soil samples and hydroponic nutrient solutions, as well as the detection of the radioactive (137)Cs isotope. PMID:26860298

  10. Biological determinants of aldosterone-induced cardiac fibrosis in rats.

    Science.gov (United States)

    Robert, V; Silvestre, J S; Charlemagne, D; Sabri, A; Trouvé, P; Wassef, M; Swynghedauw, B; Delcayre, C

    1995-12-01

    To determine the events leading to cardiac fibrosis in aldosterone-salt hypertensive rats, we studied protein and mRNA accumulation of procollagens I and III for 60 days. After 3 and 7 days of treatment systolic pressure was normal, and no histological or biochemical changes were seen in rat hearts. At day 15 arterial pressure was raised (+40%) and left ventricular hypertrophy was +15%. Cardiac examination after hemalun-eosin staining and immunolabeling with anticollagen I and III antibodies showed no structural alterations, but an 83% increase in right ventricular type III procollagen mRNA levels was found. At 30 and 60 days we found progressive cardiac fibrosis, with inflammatory cells, myocyte necrosis, and elevation of both types I and III procollagen mRNA levels in both ventricles. To determine whether aldosterone had effects on Na,K-ATPase that might lead to ionic disturbances and induce myocyte necrosis, we studied the major cardiac Na,K-ATPase isoform genes. Although Na,K-ATPase alpha 1- and beta 1-subunit mRNA levels were elevated in kidney at day 1, neither of these cardiac transcripts nor the specific alpha 2 isoform was altered between 1 and 15 days. These results show that accumulation of procollagen mRNAs occurs before collagen deposition. Cardiac alterations are late and not preceded by changes in Na,K-ATPase cardiac gene expression, precluding a direct modulation of cardiac collagen synthesis and Na,K-ATPase by aldosterone. PMID:7490157

  11. Social and Behavioral Risk Marker Clustering Associated with Biological Risk Factors for Coronary Heart Disease: NHANES 2001–2004

    Directory of Open Access Journals (Sweden)

    Nicholas J. Everage

    2014-01-01

    Full Text Available Background. Social and behavioral risk markers (e.g., physical activity, diet, smoking, and socioeconomic position cluster; however, little is known whether clustering is associated with coronary heart disease (CHD risk. Objectives were to determine if sociobehavioral clustering is associated with biological CHD risk factors (total cholesterol, HDL cholesterol, systolic blood pressure, body mass index, waist circumference, and diabetes and whether associations are independent of individual clustering components. Methods. Participants included 4,305 males and 4,673 females aged ≥20 years from NHANES 2001–2004. Sociobehavioral Risk Marker Index (SRI included a summary score of physical activity, fruit/vegetable consumption, smoking, and educational attainment. Regression analyses evaluated associations of SRI with aforementioned biological CHD risk factors. Receiver operator curve analyses assessed independent predictive ability of SRI. Results. Healthful clustering (SRI = 0 was associated with improved biological CHD risk factor levels in 5 of 6 risk factors in females and 2 of 6 risk factors in males. Adding SRI to models containing age, race, and individual SRI components did not improve C-statistics. Conclusions. Findings suggest that healthful sociobehavioral risk marker clustering is associated with favorable CHD risk factor levels, particularly in females. These findings should inform social ecological interventions that consider health impacts of addressing social and behavioral risk factors.

  12. Factors Influencing Agreement between Self-Reports and Biological Measures of Smoking among Adolescents.

    Science.gov (United States)

    Dolcini, M. Margaret; And Others

    1996-01-01

    Reviews 28 studies comparing adolescent self-report of smoking with biological indicators. Identifies four factors limiting agreement: biases in self-report due to limitations of biological measures; limitations of self-report measures; social desirability; and analytic and statistical issues. Concludes that, with optimal measurement, self-report…

  13. Biological lifestyle factors in adult distance education: predicting cognitive and learning performance

    NARCIS (Netherlands)

    Gijselaers, Jérôme

    2015-01-01

    Gijselaers, H. J. M. (2015, 20 October). Biological lifestyle factors in adult distance education: predicting cognitive and learning performance. Presentation given for the inter-faculty Data Science group at the Open University of the Netherlands, Heerlen, The Netherlands.

  14. Estimating Escherichia coli loads in streams based on various physical, chemical, and biological factors

    OpenAIRE

    Dwivedi, Dipankar; Mohanty, Binayak P.; Lesikar, Bruce J.

    2013-01-01

    Microbes have been identified as a major contaminant of water resources. Escherichia coli (E. coli) is a commonly used indicator organism. It is well recognized that the fate of E. coli in surface water systems is governed by multiple physical, chemical, and biological factors. The aim of this work is to provide insight into the physical, chemical, and biological factors along with their interactions that are critical in the estimation of E. coli loads in surface streams. There are various mo...

  15. Regression analysis of biologically effective integrated irradiances versus ozone, clouds and geometric factors

    Science.gov (United States)

    Díaz, S.; Deferrari, G.; Martinioni, D.; Oberto, A.

    2000-05-01

    Factors affecting UV radiation at the earth's surface include the solar zenith angle, earth-sun distance, clouds, aerosols, altitude, ozone and the ground's albedo. The variation of some factors, such as solar zenith angle and earth-sun distance, is well established. Total column ozone and UV radiation are inversely related, but the presence of clouds may affect the resulting UV in such a way that a depletion in the total column ozone may not always lead to an increase in the radiation at the earth's surface. The aim of this paper is to determine the contribution to the variation of the biologically effective irradiance by geometric factors, clouds and ozone, jointly and separately, in Ushuaia (54°49'S, 68°19'W, sea level), and the seasonal variation of this relationship, given the magnitude and seasonal distribution of the ozone depletion and the frequent presence of high cloud cover in this site. For this purpose, multivariate and simple regression analyses of daily and monthly integrated irradiances weighted by the DNA damage action spectrum as a function of total column ozone and the integrated irradiances in the band 337-342 nm (as a proxy for cloud cover and geometric factors) have been performed. For the analysed period (September 1989-December 1996) more than 97% of the variation of the DNA damage weighted daily integrated irradiances is described by changes in ozone, clouds and geometric factors. Simple regression analysis for daily integrated irradiances, grouped by month, shows that most of this variation is explained by clouds and geometric factors, except in spring, when strong ozone depletion occurs intermittently over this area. When monthly trends are removed, similar results are observed, except for late winter.

  16. THE EFFECT OF LEARNING ENVIRONMENT FACTORS ON BIOLOGICAL DEVELOPMENT OF FIRST YEAR STUDENTS

    Directory of Open Access Journals (Sweden)

    Podstawski Robert

    2013-12-01

    Full Text Available The purpose of the study conducted among students of UWM in Olsztyn was to diagnose the level of biological development of first year students aged 19-20 years, depending on the location and type of secondary school attended. The research on the level of physical and motor development was carried out in 2012 during the compulsory physical education classes of 361 full-time students randomly selected with the use of statistical tables out of 250 student groups. In order to determine the level of physical development, basic anthropometric parameters of the subjects were measured such as body weight and height, and 13 motor tests were used to determine the motor level. The results showed that factors such as the location and type of secondary school attended did not differentiate significantly the level of physical and motor development of first-year students, and the occurring differences were rather incidental and accidental. The weak interaction of factors used was probably the result of blurring the differences and barriers between schools operating in rural areas and in urban areas, a similar curriculum, and an 8-month stay of the subjects at university.

  17. Learner, Text, and Context Factors on Conceptual Change in Biology

    Science.gov (United States)

    Trevors, Gregory

    This thesis investigated how instructional environments might be optimally designed for all students to restructure prior knowledge and learn counter-intuitive science concepts, referred to as conceptual change. Three independent variables were examined in relation to real-time cognitive processes and subsequent learning outcomes: a learner characteristic (students' beliefs about knowledge and knowing, or epistemic beliefs), a property of instructional texts (refutational text structures), and a variable of instructional contexts (reading goals). Fifty-one university students with misconceptions in biological evolution were classified as espousing either absolutistic or evaluativist epistemic beliefs. Participants were randomly assigned to receive a refutational or expository texts and a global comprehension or elaborative interrogation reading goal in a 2x2 nested design. Data on think aloud responses while reading and open-ended essays post-reading were collected. Results reveal that refutations enriched conceptual evolutionary knowledge but failed to foster restructuring of misconceptions. Epistemic beliefs were related to cognitive processing, with evaluativists adapting their processes according to instructional texts. Reading goals likewise enriched conceptual knowledge and did not revise misconceptions, but no interaction between assigned goals and epistemic beliefs was observed. Theoretical and practical implications are discussed.

  18. Biology, Genetics, and Environment: Underlying Factors Influencing Alcohol Metabolism.

    Science.gov (United States)

    Wall, Tamara L; Luczak, Susan E; Hiller-Sturmhöfel, Susanne

    2016-01-01

    Gene variants encoding several of the alcohol-metabolizing enzymes, alcohol dehydrogenase (ADH) and aldehyde dehydrogenase (ALDH), are among the largest genetic associations with risk for alcohol dependence. Certain genetic variants (i.e., alleles)--particularly the ADH1B*2, ADH1B*3, ADH1C*1, and ALDH2*2 alleles--have been associated with lower rates of alcohol dependence. These alleles may lead to an accumulation of acetaldehyde during alcohol metabolism, which can result in heightened subjective and objective effects. The prevalence of these alleles differs among ethnic groups; ADH1B*2 is found frequently in northeast Asians and occasionally Caucasians, ADH1B*3 is found predominantly in people of African ancestry, ADH1C*1 varies substantially across populations, and ALDH2*2 is found almost exclusively in northeast Asians. Differences in the prevalence of these alleles may account at least in part for ethnic differences in alcohol consumption and alcohol use disorder (AUD). However, these alleles do not act in isolation to influence the risk of AUD. For example, the gene effects of ALDH2*2 and ADH1B*2 seem to interact. Moreover, other factors have been found to influence the extent to which these alleles affect a person's alcohol involvement, including developmental stage, individual characteristics (e.g., ethnicity, antisocial behavior, and behavioral undercontrol), and environmental factors (e.g., culture, religion, family environment, and childhood adversity).

  19. Biology, Genetics, and Environment: Underlying Factors Influencing Alcohol Metabolism.

    Science.gov (United States)

    Wall, Tamara L; Luczak, Susan E; Hiller-Sturmhöfel, Susanne

    2016-01-01

    Gene variants encoding several of the alcohol-metabolizing enzymes, alcohol dehydrogenase (ADH) and aldehyde dehydrogenase (ALDH), are among the largest genetic associations with risk for alcohol dependence. Certain genetic variants (i.e., alleles)--particularly the ADH1B*2, ADH1B*3, ADH1C*1, and ALDH2*2 alleles--have been associated with lower rates of alcohol dependence. These alleles may lead to an accumulation of acetaldehyde during alcohol metabolism, which can result in heightened subjective and objective effects. The prevalence of these alleles differs among ethnic groups; ADH1B*2 is found frequently in northeast Asians and occasionally Caucasians, ADH1B*3 is found predominantly in people of African ancestry, ADH1C*1 varies substantially across populations, and ALDH2*2 is found almost exclusively in northeast Asians. Differences in the prevalence of these alleles may account at least in part for ethnic differences in alcohol consumption and alcohol use disorder (AUD). However, these alleles do not act in isolation to influence the risk of AUD. For example, the gene effects of ALDH2*2 and ADH1B*2 seem to interact. Moreover, other factors have been found to influence the extent to which these alleles affect a person's alcohol involvement, including developmental stage, individual characteristics (e.g., ethnicity, antisocial behavior, and behavioral undercontrol), and environmental factors (e.g., culture, religion, family environment, and childhood adversity). PMID:27163368

  20. Factors determining retail banks performance : case study Ubank / Buhle Mdakane

    OpenAIRE

    Mdakane, Buhle

    2012-01-01

    The study is a case study and it investigates the factors that determine the performance of retail banks in South Africa, and follows a case study approach in which Ubank is the focus. The purpose is to rank the identified factors in their order of importance for management's focus on improving the bank's performance. Performance is examined in terms of the bank's profitability and growth. This research utilizes secondary data analysis. The quantitative method is used by critic...

  1. Rooting depths of plants relative to biological and environmental factors

    Energy Technology Data Exchange (ETDEWEB)

    Foxx, T S; Tierney, G D; Williams, J M

    1984-11-01

    In 1981 to 1982 an extensive bibliographic study was completed to document rooting depths of native plants in the United States. The data base presently contains 1034 citations with approximately 12,000 data elements. In this paper the data were analyzed for rooting depths as related to life form, soil type, geographical region, root type, family, root depth to shoot height ratios, and root depth to root lateral ratios. Average rooting depth and rooting frequencies were determined and related to present low-level waste site maintenance.

  2. Rooting depths of plants relative to biological and environmental factors

    International Nuclear Information System (INIS)

    In 1981 to 1982 an extensive bibliographic study was completed to document rooting depths of native plants in the United States. The data base presently contains 1034 citations with approximately 12,000 data elements. In this paper the data were analyzed for rooting depths as related to life form, soil type, geographical region, root type, family, root depth to shoot height ratios, and root depth to root lateral ratios. Average rooting depth and rooting frequencies were determined and related to present low-level waste site maintenance

  3. 78 FR 55326 - Determinations Regarding Use of Chemical Weapons in Syria Under the Chemical and Biological...

    Science.gov (United States)

    2013-09-10

    ... Determinations Regarding Use of Chemical Weapons in Syria Under the Chemical and Biological Weapons Control and..., 22 U.S.C. 5604(a), that the Government of Syria has used chemical weapons in violation of... Under Secretary of State for Political Affairs: (1) Determined that the Government of Syria has...

  4. 9 CFR 113.29 - Determination of moisture content in desiccated biological products.

    Science.gov (United States)

    2010-01-01

    ... 9 Animals and Animal Products 1 2010-01-01 2010-01-01 false Determination of moisture content in desiccated biological products. 113.29 Section 113.29 Animals and Animal Products ANIMAL AND PLANT HEALTH... VECTORS STANDARD REQUIREMENTS Standard Procedures § 113.29 Determination of moisture content in...

  5. Determinant Factors of the Organizations’ Involvement in Social Responsibility Programs

    OpenAIRE

    Razvan Catalin DOBREA; Aurora BURCA

    2010-01-01

    The involvement in social responsibility programs became a current practice at the organizations’ level, determined by the necessity of an approach orientated on competition and performance. The social responsibility of actions diversity imposes an approach in stages that has to correlate the organization’s interests with those of the civil society. The present paper highlights the determinant factors ensemble of the implication in social responsibility actions as well as the main difficultie...

  6. Environmental Performance in Countries Worldwide: Determinant Factors and Multivariate Analysis

    Directory of Open Access Journals (Sweden)

    Isabel Gallego-Alvarez

    2014-11-01

    Full Text Available The aim of this study is to analyze the environmental performance of countries and the variables that can influence it. At the same time, we performed a multivariate analysis using the HJ-biplot, an exploratory method that looks for hidden patterns in the data, obtained from the usual singular value decomposition (SVD of the data matrix, to contextualize the countries grouped by geographical areas and the variables relating to environmental indicators included in the environmental performance index. The sample used comprises 149 countries of different geographic areas. The findings obtained from the empirical analysis emphasize that socioeconomic factors, such as economic wealth and education, as well as institutional factors represented by the style of public administration, in particular control of corruption, are determinant factors of environmental performance in the countries analyzed. In contrast, no effect on environmental performance was found for factors relating to the internal characteristics of a country or political factors.

  7. The Five-Factor Model and Self-Determination Theory

    DEFF Research Database (Denmark)

    Olesen, Martin Hammershøj; Thomsen, Dorthe Kirkegaard; Schnieber, Anette;

    This study investigates conceptual overlap vs. distinction between individual differences in personality traits, i.e. the Five-Factor Model; and Self-determination Theory, i.e. general causality orientations. Twelve-hundred-and-eighty-seven freshmen (mean age 21.71; 64% women) completed electronic...

  8. Factors determining esthetic outcome after breast cancer conservative treatment

    DEFF Research Database (Denmark)

    Cardoso, Maria J; Cardoso, Jaime; Santos, Ana C;

    2007-01-01

    The aim of this study was to evaluate the factors that determine esthetic outcome after breast cancer conservative treatment, based on a consensual classification obtained with an international consensus panel. Photographs were taken from 120 women submitted to conservative unilateral breast canc...

  9. 40 CFR 1065.845 - Response factor determination.

    Science.gov (United States)

    2010-07-01

    ... 40 Protection of Environment 32 2010-07-01 2010-07-01 false Response factor determination. 1065.845 Section 1065.845 Protection of Environment ENVIRONMENTAL PROTECTION AGENCY (CONTINUED) AIR POLLUTION CONTROLS ENGINE-TESTING PROCEDURES Testing With Oxygenated Fuels § 1065.845 Response...

  10. SHADOW PROCESSES INSTATE BUDGET: CURRENT CONDITION AND DETERMINING FACTORS

    Directory of Open Access Journals (Sweden)

    Z. Varnalii

    2014-12-01

    Full Text Available The most significant factors that move state budget into the shadow are determined. Current condition of shadow processes in state budget is highlighted. The paper also provides an analysis of relationship between political processes and shadow economy in public sector of Ukraine.

  11. Determining Factors of Environmental Education in Spanish Universities

    Science.gov (United States)

    Larrán, Manuel; Andrades, Javier

    2015-01-01

    Purpose: This study aims to analyze the main factors that might determine the extent to which Spanish organizational management educators use environmental stand-alone subjects to equip students with alternative views of business. To give a more qualitative study, this paper also provides a more detailed curriculum analysis from a double point of…

  12. Hurdles for sport consumption? Determining factors of household sports expenditure

    NARCIS (Netherlands)

    Thibaut, Erik; Vos, Steven; Scheerder, Jeroen

    2013-01-01

    The purpose of this article is to explore the determining factors of household expenditures on sports participation. Due to a relatively large amount of zero-expenditures, simple regression methods are not suited. Because of methodological reasons, the two-step Heckman approach is used over the Tobi

  13. Diurnal rhythmicity in biological processes involved in bioavailability of functional food factors

    OpenAIRE

    Tsurusaki, Takashi; Sakakibara, Hiroyuki; Aoshima, Yoshiki; Yamazaki, Shunsuke; Sakono, Masanobu; Shimoi, Kayoko

    2013-01-01

    In the past few decades, many types of functional factors have been identified in dietary foods; for example, flavonoids are major groups widely distributed in the plant kingdom. However, the absorption rates of the functional food factors are usually low, and many of these are difficult to be absorbed in the intact forms because of metabolization by biological processes during absorption. To gain adequate beneficial effects, it is therefore mandatory to know whether functional food factors a...

  14. Chemical modifiers in arsenic determination in biological materials by tungsten coil electrothermal atomic absorption spectrometry

    Energy Technology Data Exchange (ETDEWEB)

    Bruhn, C.G.; Huerta, V.N.; Neira, J.Y. [Departamento de Analisis Instrumental, Facultad de Farmacia, Universidad de Concepcion, P.O. Box 237, Concepcion (Chile)

    2004-01-01

    Palladium, iridium, and rhodium are evaluated as possible chemical modifiers in the determination of As in digest solutions of biological materials (human hair and clam) by tungsten coil electrothermal atomic absorption spectrophotometry (TCA-AAS). The modifier in solution was applied onto the coil and thermally pre-reduced; the pre-reduction conditions, the amount of modifier, and the thermal program were optimized. Palladium was not satisfactory, whereas Ir and Rh were effective modifiers and rendered better relative sensitivity for As by a factor of 1.4 and 1.9, respectively compared to the case without modifier. Upon optimization of thermal conditions for As in pre-reduced Ir (2.0 {mu}g) and Rh (2.0 {mu}g) modifiers and in the digest solutions of the study matrices, Rh (2.0 {mu}g) was more effective modifier and was selected as such. The mean within-day repeatability was 2.8% in consecutive measurements (25-100 {mu}g L{sup -1}) (3 cycles, each of n=6) and confirmed good short-term stability of the absorbance measurements. The mean reproducibility was 4.4% (n=20 in a 3-day period) and the detection limit (3{sigma}{sub blank}/slope) was 29 pg (n=15). The useful coil lifetime in Rh modifier was extended to 300-400 firings. Validation was by determination of As in the certified reference material (CRM) of ''Oyster tissue'' solution with a percentage relative error (E{sub rel}%) of 2% and percentage relative standard deviation (RSD%) of 3% (n=4), and by analytical recovery of As spiked in CRM of human hair [94{+-}8% (n=4)]. The methodology is simple, fast (sample readout frequency 21 h{sup -1}), reliable, of low cost, and was applied to the determination of As in hair samples of exposed and unexposed workers. (orig.)

  15. Recovery from equipment failures in ATC: Determination of contextual factors

    International Nuclear Information System (INIS)

    Human reliability assessment (HRA) currently uses various approaches to determine and quantify human error. These approaches are increasingly being employed in various safety-critical domains, such as air traffic management and its ground component air traffic control. HRA research over the years has shown the important role of the context in which human errors take place. Recent techniques now put more emphasis on the definition of key contextual factors and their impact on the reliability of human performance. This paper presents a review of the current understanding of contextual factors in various industries. It uses this together with results from controller interviews to identify the contextual factors relevant to controller recovery from equipment failures in air traffic control. These factors should be used in conjunction with an appropriate method to analyse the performance of a controller during the process of recovery from failures

  16. Direct and indirect effects of biological factors on extinction risk in fossil bivalves

    OpenAIRE

    Harnik, Paul G.

    2011-01-01

    Biological factors, such as abundance and body size, may contribute directly to extinction risk and indirectly through their influence on other biological characteristics, such as geographic range size. Paleontological data can be used to explicitly test many of these hypothesized relationships, and general patterns revealed through analysis of the fossil record can help refine predictive models of extinction risk developed for extant species. Here, I use structural equation modeling to tease...

  17. Lifestyle and dietary factors determine age at natural menopause.

    Science.gov (United States)

    Sapre, Shilpa; Thakur, Ratna

    2014-01-01

    A literature search was done using PubMed. The age at natural menopause (ANM) depends on various factors like genetic, environmental, socioeconomic, reproductive, dietary, and lifestyle of which some like nulliparity, vegetarian diet, smoking, high fat intake, cholesterol, and caffeine accelerates; while others like parity, prior use of oral contraceptive pills, and Japanese ethnicity delays the ANM. ANM is an important risk factor for long-term morbidity and mortality; and hence, the need to identify the modifiable risk factors like diet and lifestyle changes. Delayed menopause is associated with increased risk of endometrial and breast cancer, while early ANM enhances the risk for cardiovascular diseases and osteoporosis. The correlation between diet and ANM has not been extensively studied; however, whatever studies have been done till now point towards role of high intake of total calories, fruits, and proteins in delaying the ANM, while high polyunsaturated fat intake accelerates it. The role of dietary soy, total fat, saturated fat, red meat, and dietary fiber in determining the ANM has been controversial and needs further studies to substantiate it. The lifestyle factors like current smoking and vigorous exercise have been significantly associated with early menopause, while moderate alcohol consumption delays the ANM. Large prospective studies are needed to study the association of ANM and other modifiable factors like passive smoking fish consumption, soy, and various types of tea. The knowledge of modifiable determinants of ANM can help in setting up menopausal clinics and initiating health programs specially in developing countries. PMID:24672198

  18. Lifestyle and dietary factors determine age at natural menopause.

    Science.gov (United States)

    Sapre, Shilpa; Thakur, Ratna

    2014-01-01

    A literature search was done using PubMed. The age at natural menopause (ANM) depends on various factors like genetic, environmental, socioeconomic, reproductive, dietary, and lifestyle of which some like nulliparity, vegetarian diet, smoking, high fat intake, cholesterol, and caffeine accelerates; while others like parity, prior use of oral contraceptive pills, and Japanese ethnicity delays the ANM. ANM is an important risk factor for long-term morbidity and mortality; and hence, the need to identify the modifiable risk factors like diet and lifestyle changes. Delayed menopause is associated with increased risk of endometrial and breast cancer, while early ANM enhances the risk for cardiovascular diseases and osteoporosis. The correlation between diet and ANM has not been extensively studied; however, whatever studies have been done till now point towards role of high intake of total calories, fruits, and proteins in delaying the ANM, while high polyunsaturated fat intake accelerates it. The role of dietary soy, total fat, saturated fat, red meat, and dietary fiber in determining the ANM has been controversial and needs further studies to substantiate it. The lifestyle factors like current smoking and vigorous exercise have been significantly associated with early menopause, while moderate alcohol consumption delays the ANM. Large prospective studies are needed to study the association of ANM and other modifiable factors like passive smoking fish consumption, soy, and various types of tea. The knowledge of modifiable determinants of ANM can help in setting up menopausal clinics and initiating health programs specially in developing countries.

  19. Biological determinants of photobioreactor design. 1st Quarterly report, September 1, 1993--November 30, 1993

    Energy Technology Data Exchange (ETDEWEB)

    Palsson, B.O.; Brown, G.G.

    1994-05-01

    Microalgae is being considered for capture and sequestration Of CO{sub 2} from power-plant flue-gases. High productivity of microalgae is necessary to make this process cost effective compared to the conventional methods used for reducing CO{sub 2} levels in the atmosphere. This obviates the need for large-scale cultivation technologies and proper photobioreactor technology. The physical factors that influence the performance of a photoautotrophic microalgal culture are the quality and composition of light, inlet carbon dioxide concentration, nutrients, and secondary metabolites at high cell densities. In developing photobioreactor technology, balancing of biological processes to the physical rate process becomes important. In this first quarterly report, the effect of various light compositions on the culture kinetics is studied. To determine the optimal composition, six wavelengths 470, 555, 560, 570, 580 and 605, each supplemented with 680 nm were used to cultivate cultures. Based on the results obtained it is concluded that a monochromatic red light of 680 nm is sufficient to obtain the maximum capacity.

  20. A local factorization of the fermion determinant in lattice QCD

    CERN Document Server

    Cè, Marco; Schaefer, Stefan

    2016-01-01

    We introduce a factorization of the fermion determinant in lattice QCD with Wilson-type fermions that leads to a bosonic action local in the block fields. The interaction among gauge fields on distant blocks is mediated by multiboson fields located on the boundaries of the blocks. The resultant multiboson domain-decomposed hybrid Monte Carlo passes extensive numerical tests carried out by measuring standard gluonic observables. The combination of the determinant factorization and of the one of the propagator, that we put forward recently, paves the way for multilevel Monte Carlo integration in presence of fermions. We test this possibility by computing the disconnected correlator of two flavor-diagonal pseudoscalar densities, and we observe a significant increase of the signal-to-noise ratio due to a two-level integration.

  1. An analysis of the structure of the compound biological effectiveness factor

    Science.gov (United States)

    Ono, Koji

    2016-01-01

    This report is an analysis of the structure of the compound biological effectiveness (CBE) factor. The value of the CBE factor previously reported was revalued for the central nervous system, skin and lung. To describe the structure, the following terms are introduced: the vascular CBE (v-CBE), intraluminal CBE (il-CBE), extraluminal CBE (el-CBE) and non-vascular CBE (nv-CBE) factors and the geometric biological factor (GBF), i.e. the contributions that are derived from the total dose to the vasculature, each dose to vasculature from the intraluminal side and the extraluminal side, the dose to the non-vascular tissue and the factor to calculate el-CBE from il-CBE, respectively. The el-CBE factor element was also introduced to relate il-CBE to el-CBE factors. A CBE factor of 0.36 for disodium mercaptoundecahydrododecaborate (BSH) for the CNS was independent of the 10B level in the blood; however, that for p-Boron-L-phenylalanine (BPA) increased with the 10B level ratio of the normal tissue to the blood (N/B). The CBE factor was expressed as follows: factor = 0.32 + N/B × 1.65. The factor of 0.32 at 0 of N/B was close to the CBE factor for BSH. GBFs had similar values, between BSH and BPA, 1.39 and 1.52, respectively. The structure of the CBE factor for BPA to the lung was also elucidated based on this idea. The factor is described as follows: CBE factor = 0.32 + N/B × 1.80. By this elucidation of the structure of the CBE factor, it is expected that basic and clinical research into boron neutron capture therapy will progress. PMID:27021218

  2. Measuring performance and determining success factors of construction sites

    OpenAIRE

    Salminen, Juha

    2005-01-01

    Construction site performance has been measured using various key figures and monitored with the aid of checklists, but no systematic, comprehensive performance measurement systems exist for comparison and development purposes. The aim of the study was to develop a system for measuring and developing construction site performance, and to determine the central success factors for a construction site by analyzing the measurement results. The performance measurement system developed was base...

  3. Determination of mixing factors for VVER-440 fuel assembly head

    International Nuclear Information System (INIS)

    CFD models have been developed for the heads of the old, the present and new type VVER-440 fuel assemblies using the experiences of former validation process. With these models, temperature distributions were investigated in typical assemblies and in-core thermocouple signals were calculated. The analyses show that coolant mixing is intensive but not-perfect in the assembly heads. Difference between the thermocouple signal and cross-sectional average temperature at measurement level depends on the assembly type. Using the models, weight factors of the rod bundle regions for the in-core thermocouple have been determined. With these factors, the thermocouple signals were estimated and results were statistically tested using the registered data of the Hungarian nuclear power plant. This test shows that deviations between measured and calculated temperatures can be significantly decreased and consequently monitoring uncertainties can be reduced with using the weight factors. (author)

  4. How to Determine Experimentally the Fano Factor in DROIDs

    Science.gov (United States)

    Samedov, Victor V.

    2009-12-01

    The method of experimental determination of the Fano factor in superconducting materials is based on usage of two sensor signals of a distributed readout imaging detector (DROID). In detector of this type a photon is absorbed in a superconducting layer with two superconducting tunnel junctions (STJs) at the ends. In this work it is shown, that the correlation between the two STJ signals depends on the fundamental combination of the Fano factor and the effective energy of quasiparticle formation in the superconducting material of DROID. The suggested formula for this fundamental combination depends on the energy of a primary particle, on the mean values of STJs' signal amplitudes, and on the variances of the sum and the difference of the STJs' signals. As this fundamental combination depends on the energy of a primary particle and on the particle interaction point, then it should depend on the local physical properties of the absorber. Independent determination of the effective energy of quasiparticle formation allows one to determine the value of the Fano factor. The important advantage of proposed method is its independence from the STJs' electronic gains and noise.

  5. Relative biological effectiveness and radiation weighting factors in the context of animals and plants

    International Nuclear Information System (INIS)

    Radiation weighting factors have long been employed to modify absorbed dose as part of the process of evaluating radiological impact to humans. Their use represents an acknowledgement of the fundamental difference in energy deposition patterns of charged and uncharged particles, and how this can translate into varying degrees of biological impact. Weighting factors used in human radiation protection are derived from a variety of endpoints taken from in-vitro experiments that include human and animal cell lines, as well as in-vivo experiments with animals. Nonetheless, the application of radiation weighting factors in the context of dose assessment of animals and plants is not without some controversy. Specifically, radiation protection of biota has largely focused on limiting deterministic effects, such as reduced reproductive fitness. Consequently, the application of conventional stochastic-based radiation weighting factors (when used for human protection) appears inappropriate. While based on research, radiation weighting factors represent the parsing of extensive laboratory studies on relative biological effectiveness. These studies demonstrate that the magnitude of a biological effect depends not just on dose, but also on other factors including the rate at which the dose is delivered, the type and energy of the radiation delivering the dose, and, most importantly, the endpoint under consideration. This article discusses the efforts taken to develop a logical, transparent, and defensible approach to establishing radiation weighting factors for use in assessing impact to non-human biota, and the challenges found in differentiating stochastic from deterministic impacts.

  6. Use of cloud-point preconcentration for spectrophotometric determination of trace amounts of antimony in biological and environmental samples.

    Science.gov (United States)

    El-Sharjawy, Abdel-Azeem M; Amin, Alaa S

    2016-01-01

    This work presents a cloud-point extraction process using the micelle-mediated extraction method for simultaneous preconcentration and determination of Sb(III) and Sb(V) species in biological and environmental samples as a prior preconcentration step to their spectrophotometric determination. The analytical system is based on the selective reaction between Sb(III) and 3-dichloro-6-(3-carboxy-2-hydroxy-1-naphthylazo)quinoxaline (DCHNAQ) in the presence of cetyltrimethylammonium bromide (CTAB) and potassium iodide at pH 4.5. Total Sb concentration was determined after reduction of Sb(V) to Sb(III) in the presence of potassium iodide and ascorbic acid. The optimal reaction conditions and extraction were studied, and the analytical characteristics of the method (e.g., limits of detection and quantification, linear range, preconcentration, improvement factors) were obtained. Linearity for Sb(III) was obeyed in the range of 0.2-20 ng ml(-1). The detection and quantification limits for the determination of Sb(III) were 0.055 and 0.185 ng ml(-1), respectively. The method has a lower detection limit and wider linear range, inexpensive instrument, and low cost, and is more sensitive compared with most other methods. The interference effect of some anions and cations was also studied. The method was applied to the determination of Sb(III) in the presence of Sb(V) and total antimony in blood plasma, urine, biological, and water samples.

  7. Teachers' conceptions of biological determinism in five countries: Denmark, Estonia, Finland, France and Italy

    OpenAIRE

    Clément, Pierre, 1809-1870.; Castéra, Jérémy

    2013-01-01

    e-book: http://www.esera.org/media/eBook_2013/strand%2012/Pierre_Clement_09Jan2014.pdf International audience The interaction between the genome and its environment (epigenetics) is a new paradigm in biology. Nevertheless, the notion of genetic determinism is still present in syllabuses and textbooks. What about teachers' conceptions? We analyzed the teachers' conceptions related to the genetic determinism of human performances in five European countries, using 24 questions of the Biohe...

  8. X-ray spectrometric determination of thorium in bone and other biological materials

    International Nuclear Information System (INIS)

    An x-ray spectrometric method has been developed for the determination of thorium in bone and other biological materials. The limit of detection at the 95% confidence level is 20 ng. This corresponds to a concentration of 2 ppb in a 10-g sample of bone ash

  9. Selenium determination in biological material by atomic absorption spectrophotometry in graphite furnace and using vapor generation

    International Nuclear Information System (INIS)

    The applicability of the atomic absorption spectrophotometry to the determination of selenium in biological material using vapor generation and electrothermal atomization in the graphite furnace was investigated. Instrumental parameters and the analytical conditions of the methods were studied. Decomposition methods for the samples were tested, and the combustion in the Wickbold apparatus was chosen. (author)

  10. Simultaneous Determination of Arsenic, Manganese, and Selenium in Biological Materials by Neutron-Activation Analysis

    DEFF Research Database (Denmark)

    Heydorn, Kaj; Damsgaard, Else

    1973-01-01

    A new method was developed for the simultaneous determination of arsenic, manganese, and selenium in biological material by thermal-neutron activation analysis. The use of 81 mSe as indicator for selenium permitted a reduction of activation time to 1 hr for a 1 g sample, and the possibility of loss...

  11. Intracellular biology and virulence determinants of Francisella tularensis revealed by transcriptional profiling inside macrophages

    OpenAIRE

    Wehrly, Tara D.; Chong, Audrey; Virtaneva, Kimmo; Sturdevant, Dan E.; Child, Robert; Edwards, Jessica A.; Brouwer, Dedeke; Nair, Vinod; Fischer, Elizabeth R.; Wicke, Luke; Curda, Alissa J.; Kupko, John J.; Martens, Craig; Crane, Deborah D.; Bosio, Catharine M.

    2009-01-01

    The highly infectious bacterium Francisella tularensis is a facultative intracellular pathogen, whose virulence requires proliferation inside host cells, including macrophages. Here we have performed a global transcriptional profiling of the highly virulent F. tularensis subsp. tularensis Schu S4 strain during its intracellular cycle within primary murine macrophages, to characterize its intracellular biology and identify pathogenic determinants based on their intracellular expression profile...

  12. Sex determination meltdown upon biological control introduction of the parasitoid Cotesia rubecula?

    NARCIS (Netherlands)

    de Boer, Jetske G.; Kuijper, Bram; Heimpel, George E.; Beukeboom, Leo W.

    2012-01-01

    Natural enemies may go through genetic bottlenecks during the process of biological control introductions. Such bottlenecks are expected to be particularly detrimental in parasitoid Hymenoptera that exhibit complementary sex determination (CSD). CSD is associated with a severe form of inbreeding dep

  13. Medico-biological factors of speech and language development in young children (part 1)

    OpenAIRE

    Chernov D.N.

    2015-01-01

    The article analyzed the main results of medico-biological directions in the study of the factors of children's speech and language. It shows that a variety of pre-, peri-and neonatal developmental factors (teratogenic effects, prematurity, low birth weight, maternal diseases during pregnancy, and chronic diseases of the child) had a negative impact on the child-parent relationship that has a lasting influence on child speech and language development.

  14. Stability and biological activity evaluations of PEGylated human basic fibroblast growth factor

    OpenAIRE

    Hadadian, Shahin; Shamassebi, Dariush Norouzian; Mirzahoseini, Hasan; Shokrgozar, Mohamad Ali; Bouzari, Saeid; Sepahi, Mina

    2015-01-01

    Background: Human basic fibroblast growth factor (hBFGF) is a heparin-binding growth factor and stimulates the proliferation of a wide variety of cells and tissues causing survival properties and its stability and biological activity improvements have received much attention. Materials and Methods: In the present work, hBFGF produced by engineered Escherichia coli and purified by cation exchange and heparin affinity chromatography, was PEGylated under appropriate condition employing 10 kD pol...

  15. Principles of biological adaptation of microorganisms to the change of environmental factors in artificial ecosystems

    Science.gov (United States)

    Somova, L. A.; Pisman, T. I.

    Studying the matter transformations and biotic cycling in artificial ecosystems (AES), we need to know the principles of biological adaptation of active organisms to the change of environment. Microorganisms in AES of water purification are the most active transform and consumers of organic substances of wastes. Utilization of organic substances is directly connected with the energy fluxes used by AES. According to energy criteria, the energy fluxes used by biological system have trends to maximum values under stable conditions. Nonutilized substrate concentration decreases in result of biological adaptations. After sharp change of environmental factors, for example, after sharp increase of flow rate of organic substances, the biological system is not able to react quickly. The concentration of nonutilized substrate increases and the energy flux used by biological system decreases. The structure of microbial community also changes, having the decrease of biological diversity. Later, as a result of biological adaptation, the ecological and evolution processes bring to decreasing the concentration of nonutilized substrate and to energy fluxes increasing. To compare with natural ecosystems, AES allow to follow and to study these processes quickly and quantitatively.

  16. Psoriasis in the US Medicare Population: Prevalence, Treatment, and Factors Associated with Biologic Use.

    Science.gov (United States)

    Takeshita, Junko; Gelfand, Joel M; Li, Penxiang; Pinto, Lionel; Yu, Xinyan; Rao, Preethi; Viswanathan, Hema N; Doshi, Jalpa A

    2015-12-01

    Psoriasis is a common chronic inflammatory disorder, primarily of the skin. Despite an aging population, knowledge of the epidemiology of psoriasis and its treatments among the elderly is limited. We examined the prevalence of psoriasis and its treatments, with a focus on biologics and identification of factors associated with biologic use, using a nationally representative sample of Medicare beneficiaries in 2011. On the basis of several psoriasis identification algorithms, the claims-based prevalence for psoriasis in the United States ranged from 0.51 to 1.23%. Treatments used for moderate-to-severe psoriasis (phototherapy, oral systemic, or biologic therapies) were received by 27.3% of the total psoriasis sample, of whom 37.2% used biologics. Patients without a Medicare Part D low-income subsidy (LIS) had 70% lower odds of having received biologics than those with LIS (odds ratio 0.30; 95% confidence interval, 0.19-0.46). Similarly, the odds of having received biologics were 69% lower among black patients compared with white patients (0.31; 0.16-0.60). This analysis identified potential financial and racial barriers to receipt of biologic therapies and underscores the need for additional studies to further define the epidemiology and treatment of psoriasis among the elderly.

  17. Psoriasis in the U.S. Medicare population: prevalence, treatment, and factors associated with biologic use

    Science.gov (United States)

    Takeshita, Junko; Gelfand, Joel M.; Li, Penxiang; Pinto, Lionel; Yu, Xinyan; Rao, Preethi; Viswanathan, Hema N.; Doshi, Jalpa A.

    2015-01-01

    Psoriasis is a common chronic inflammatory disorder, primarily of the skin. Despite an aging population, knowledge of the epidemiology of psoriasis and its treatments among the elderly is limited. We examined the prevalence of psoriasis and its treatments, with a focus on biologics and identification of factors associated with biologic use, using a nationally representative sample of Medicare beneficiaries in 2011. Based on several psoriasis identification algorithms, the claims-based prevalence for psoriasis in the United States ranged from 0.51% to 1.23%. Treatments employed for moderate to severe psoriasis (phototherapy, oral systemic, or biologic therapies) were received by 27.3% of the total psoriasis sample, of whom 37.2% used biologics. Patients without Medicare Part D low-income subsidies had 70% lower odds of having received biologics than those with low-income subsidies (odds ratio 0.30; 95% confidence interval, 0.19– 0.46). Similarly, the odds of having received biologics was 69% lower among black patients than white patients (0.31; 0.16–0.60). This analysis identified potential financial and racial barriers to receipt of biologic therapies and underscores the need for additional studies to further define the epidemiology and treatment of psoriasis among the elderly. PMID:26214380

  18. Time after time: biological factors in the course of recurrent depression

    NARCIS (Netherlands)

    A. Lok

    2013-01-01

    The primary focus of this dissertation was to increase the knowledge about possible biological factors and psychopathological mechanisms (including HPA-axis functioning, one-carbon and fatty-acid metabolism), as well as some gene-environment interactions for the course of recurrent MDD (MDD-R). Stud

  19. Simultaneous determination of arsenic and selenium in biological samples by HG-AFS

    Energy Technology Data Exchange (ETDEWEB)

    Sun, Hanwen; Liu, Zhanfeng; Shi, Hongmei [Hebei University, College of Chemistry and Environmental Science, Baoding (China); Wu, Wenjuan [Third Hospital of Hebei Medical University, Department of Radiology, Shijiazhuang 050051 (China); Li, Liqing [Hebei University, College of Chemistry and Environmental Science, Baoding (China); Taishan College, Department of Chemistry, Shan Dong Taian (China)

    2005-06-01

    A new method is proposed for simultaneous determination of traces of arsenic (As) and selenium (Se) in biological samples by hydride-generation double-channel non-dispersive atomic-fluorescence spectrometry (HG-AFS) from tartaric acid media. The effects of analytical conditions on fluorescence signal intensity were investigated and optimized. Interferences from coexisting ions were evaluated. Under optimum conditions linear response ranges above 20 {mu}g L{sup -1} for As and 32 {mu}g L{sup -1} for Se were obtained with detection limits of 0.13 and 0.12 {mu}g L{sup -1}, respectively. The precision for elevenfold determination of As at the 4 {mu}g L{sup -1} level and of Se at the 8 {mu}g L{sup -1} level were 2.7 and 1.9% (RSD), respectively. Recoveries of 92.5-95.5% for As and 101.2-108.4% for Se were obtained for four biological samples and two certified biological reference materials. The proposed method has the advantages of simple operation, high sensitivity, and high efficiency; it was successfully used for simultaneous determination of As and Se in biological samples. (orig.)

  20. A review on determination of steroids in biological samples exploiting nanobio-electroanalytical methods.

    Science.gov (United States)

    Yadav, Saurabh K; Chandra, Pranjal; Goyal, Rajendra N; Shim, Yoon-Bo

    2013-01-31

    The applications of nanomaterial modified sensors, molecularly imprinting polymer based, aptamer based, and immunosensors have been described in the determination of steroids using electroanalytical techniques. After a brief description of the steroids and assays in biological fluids, the principles of electrochemical detection with the advantages and the limitations of the various sensors are presented. The nanomaterial modified sensors catalyze the oxidation/reduction of steroids and are suitable for sensing them in environmental samples and biological fluids. The determination of steroids based on their reduction has been found more useful in comparison to oxidation as the common metabolites present in the biological fluids do not undergo reduction in the usual potential window and hence, do not interfere in the determination. The sensors based on immunosensors and aptamers were found more sensitive and selective for steroid determination. Conducting polymer modified bio-sensors and microchip devices are suggested as possible future prospects for the ultra sensitive and simultaneous determination of steroids and their metabolites in various samples.

  1. Of arrows and flows. Causality, determination, and specificity in the Central Dogma of molecular biology.

    Science.gov (United States)

    Fantini, Bernardino

    2006-01-01

    From its first proposal, the Central Dogma had a graphical form, complete with arrows of different types, and this form quickly became its standard presentation. In different scientific contexts, arrows have different meanings and in this particular case the arrows indicated the flow of information among different macromolecules. A deeper analysis illustrates that the arrows also imply a causal statement, directly connected to the causal role of genetic information. The author suggests a distinction between two different kinds of causal links, defined as 'physical causality' and 'biological determination', both implied in the production of biological specificity. PMID:18351053

  2. Determination of uranium in seawater, biological samples and sediments using laser induced fluorescence spectrometry

    International Nuclear Information System (INIS)

    Uranium has been determined in seawater, biological samples and sediments using laser induced fluorescence spectrometry (LIFS). The biological samples and sediments are digested with a mixture of HNO3, HClO4 and HF. The conductivity of the seawater should be below 5.0 mS and the pH of the sample should be in the range 6.5-9.0. The volume of the reagent used to enhance the fluorescence intensity was 0.5 ml. Comparison with other methods was favorable, LIFS being rapid, simple and sensitive, and well suited to environmental monitoring. (author)

  3. Analytical methods for vancomycin determination in biological fluids and in pharmaceuticals

    Directory of Open Access Journals (Sweden)

    Marta Maria Duarte Carvalho Vila

    2007-04-01

    Full Text Available Vancomycin is a glycopeptide antibiotic employed in the treatment of infections caused by certain methicillin-resistant staphylococci. It is indicated also for patients allergic to penicillin or when there is no response to penicillins or cephalosporins. The adequate vancomycin concentration levels in blood serum lies between 5 and 10 mg/L. Higher values are toxic, causing mainly nephrotoxicity and ototoxicity. Various analytical methods are described in the literature: spectrophotometric, immunologic, biologic and chromatographic methods. This paper reviews the main analytical methods for vancomycin determination in biological fluids and in pharmaceutical preparations.

  4. About the significance of biological factors affecting pregnancy a married couple

    Directory of Open Access Journals (Sweden)

    V. V. Yarman

    2014-11-01

    Full Text Available A brief review of the literature analysis of the importance and interdependence of the main factors influencing the occurrence of pregnancy as a pair in the treatment of infertility, such as the woman's age, ovarian reserve, the semen of a man and the duration of infertility. The review also presents the data concerning the practical implications of sexual constitution and sexual maturation in men and women in the pubertal period. When evaluating male fertility invariably significant factor in the prediction of pregnancy are, impregnating ability to ejaculate. Infertility is more common in males with delayed development in the pubertal period with a weak type of sexual constitution. Results of treatment of male infertility, the dynamics of the semen and pregnancy of the couple on the background of pathogenetic therapy correlates with the type of sexual constitution. Widely deployed discussion about the existence of the male equivalent of female menopause mainly concerns the problems of men's sexual health. Of exceptional importance for the prediction of treatment of infertility has ovarian reserve, which is closely associated with age women. Formation of menstrual function occurs in the pubertal period of sexual development, in this age of menarche is the leading symptom of type of sexual constitution of women that do not change throughout the life hereafter. The presence of menstrual function and even ovulation does not reflect the reproductive capacity of women. Insufficient information content of the chronological age of a woman, as an indicator of the reproductive capacity of ovarian dictates the necessity of the development of tests that determine individual biological age of a woman, perhaps connected with the type of sexual constitution. In this regard, the study of sexual constitution partners is of great scientific and practical interest.

  5. Insights into virulence factors determining the pathogenicity of Cronobacter sakazakii.

    Science.gov (United States)

    Singh, Niharika; Goel, Gunjan; Raghav, Mamta

    2015-01-01

    Cronobacter sakazakii is an opportunistic pathogen associated with outbreaks of life-threatening necrotizing enterocolitis, meningitis and sepsis in neonates and infants. The pathogen possesses an array of virulence factors which aid in tissue adhesion, invasion and host cell injury. Although the identification and validation of C. sakazakii virulence factors has been hindered by availability of suitable neonatal animal model, various studies has reported outer membrane protein A (ompA) as a potential virulence marker. Various other plasmid associated genes such as filamentous hemagglutinin (fhaBC), Cronobacter plasminogen activator (cpa) and genes responsible for iron acquisition (eitCBAD and iucABD/iutA) have been reported in different strains of C. sakazakii. Besides these proposed virulence factors, several biophysical growth factors such as formation of biofilms and resistance to various environmental stresses also contributes to the pathogenic potential of this pathogen. This review provides an update on virulence determinants associated with the pathogenesis of C. sakazakii. The potential reservoirs of the pathogen, mode of transmission and epidemiology are also discussed. PMID:25950947

  6. Obesity trends and determinant factors in Latin America

    Directory of Open Access Journals (Sweden)

    Kain Juliana

    2003-01-01

    Full Text Available Obesity rates have increased markedly in Latin America, especially during the last 10-15 years, becoming a public health problem in most countries. Prevalence of obesity among preschool children remains low, while among schoolchildren it has increased considerably. Prevalence is high in the adult population, especially among women with less schooling. In developed populations, obesity occurs more frequently among the poor; the opposite occurs in less developed societies, where in households undergoing nutritional transition, underweight can coexist with obesity. The most important determinant factors involved in the increasing obesity prevalence are fetal and infant nutritional conditions (stunting, education and socioeconomic conditions, dietary changes (especially increased total energy intake, and physical inactivity. Because chronic diseases are the main causes of death in the Region and obesity is one of the main risk factors for these diseases, policies to improve economic and educational levels with the implementation of health promotion and prevention should be a priority in every country.

  7. Factor H-related proteins determine complement-activating surfaces.

    Science.gov (United States)

    Józsi, Mihály; Tortajada, Agustin; Uzonyi, Barbara; Goicoechea de Jorge, Elena; Rodríguez de Córdoba, Santiago

    2015-06-01

    Complement factor H-related proteins (FHRs) are strongly associated with different diseases involving complement dysregulation, which suggests a major role for these proteins regulating complement activation. Because FHRs are evolutionarily and structurally related to complement inhibitor factor H (FH), the initial assumption was that the FHRs are also negative complement regulators. Whereas weak complement inhibiting activities were originally reported for these molecules, recent developments indicate that FHRs may enhance complement activation, with important implications for the role of these proteins in health and disease. We review these findings here, and propose that FHRs represent a complex set of surface recognition molecules that, by competing with FH, provide improved discrimination of self and non-self surfaces and play a central role in determining appropriate activation of the complement pathway.

  8. [ELISA method for the determination of factor VII antigen].

    Science.gov (United States)

    Jorquera, J I; Aznar, J A; Monteagudo, J; Montoro, J M; Casaña, P; Pascual, I; Bañuls, E; Curats, R; Llopis, F

    1989-12-01

    The low plasma concentration of clotting factor VII makes it difficult to assay its antigenic fraction by the conventional methods of precipitation with specific antigens. Simple and peroxidase-conjugated antisera are currently available from commercial sources, thus allowing one to determine F VII:Ag by enzyme immunoassay. An ELISA method has been developed in this laboratory which provides sensitivity limits about 0.1% of the plasma concentration of F VII and correlates significantly with its functional activity (r = 0.603, n = 44, p less than 0.001). This technique can be highly helpful in characterising molecular variants of F VII, as well as in detecting acquired deficiencies of this factor.

  9. The determination of retainable phosphorus, relative biological availability, and relative biological value of phosphorus sources for broilers.

    Science.gov (United States)

    Coon, C N; Seo, S; Manangi, M K

    2007-05-01

    A 10- to 21-d chick bioassay was conducted to determine the absolute retention value (ARV) for 2 different defluorinated phosphates (DF-1 and DF-2) and a reagent grade dicalcium phosphate (DCP). The total and test P in excreta regressed on feed P levels were subjected to general straight-line (linear), 1-slope broken-line, 2-slope broken-line, and polynomial regression methods to find the best analysis model. The relative biological availability (RBA) and relative biological value (RBV) for P from the 2 different defluorinated phosphates (DF-1 and DF-2) were obtained by the slope ratio method using 3 different bone measurements (% tibia ash, tibia breaking force, tibia weight) and RBV calculated using percentage tibia ash, weight gain, and feed/gain. The DCP was used as reference standard for RBA and RBV. The ARV measured at the breakpoints for test P by 2-slope analysis were determined to be 82.99% for DCP, 76.34% for DF-1, and 70.30% for DF-2. The ARV of test P determined at 0.45% NPP was 62.41% for DCP, 63.58% for DF-1, and 59.25% for DF-2. The relationship of ARV and RBA were similar in that DCP was 6% higher in ARV at the breakpoint compared with DF-1 and the RBA of DF-1 was 71 and 91% from tibia weight and tibia breaking force, respectively, compared with the bone parameters from chicks fed DCP. The DF-1 phosphate had 3 and 7% higher ARV at the breakpoint and 0.45% NPP, respectively, compared with DF-2. The RBA of DF-2 was 59 and 80% from tibia weight and bone-breaking force. The ARV of phosphate sources were independent of an arbitrary reference. The ARV for P sources provide retainable P information for industry-based feed formulation that can reduce excess P in poultry waste. The excreta P data from broilers fed increasing levels of DCP indicates that the data are best described statistically with a 1-slope broken-line regression, 2-slope broken-line regression, or polynomial regression.

  10. Regulation of mutagenesis by exogenous biological factors in the eukaryotic cell systems

    Directory of Open Access Journals (Sweden)

    Lukash L. L.

    2013-07-01

    Full Text Available The representations of the mutations and the nature of spontaneous mutation process and mutagenesis induced by exogenous oncoviruses, DNAs and proteins-mitogens are analysed. Exogenous biological factors induce DNA damages in regulatory-informational way, acting on the cellular systems for maintenance of genetical stability. Molecular mechanisms are the same as at spontaneous mutagenesis but they are realized with the participation of alien genetical material. Among biological mutagens, the oncoviruses and mobile genetic elements (MGEs are distinguished as the strongest destabilizing factors which direct tumor transformation of somatic mammalian cells. Genetical reprogramming or changing the programs of gene expression at the differentiation of stem and progenitor cells under growth factors and citokines is probably followed by mutations and recombinations as well.

  11. Cloud-point extraction, preconcentration and spectrophotometric determination of trace quantities of copper in food, water and biological samples.

    Science.gov (United States)

    Gouda, Ayman A; Amin, Alaa S

    2014-01-01

    A new, simple and sensitive cloud point extraction procedure was presented for the preconcentration and determination of copper(II) ion in food, water and biological samples. The analyte was complexed with a new synthesized reagent, 2-amino-4-(m-tolylazo)pyridine-3-ol (ATAP) as a new complexing agent and Triton X-114 as the surfactant. After centrifugation, dilution of the surfactant-rich phase with 0.4 mL of ethanol acidified with 1.0M HNO3 was performed after phase separation, and the copper contents were measured by spectrophotometry at λmax 608 nm. The influence of analytical parameters including concentration of complexing agent, Triton X-114, pH, equilibration temperature and time, centrifuge rate and time were optimized. The analytical characteristics of the method (e.g. linear range, molar absorptivity, Sandell sensitivity, optimum Ringbom concentration ranges limits of detection and quantification, preconcentration factor, and improvement factors) were obtained. Linearity was obeyed in the range of 4.0-115 ng mL(-1) of Cu(II) ion. The detection and quantification limits of the method were 1.20 and 3.94 ng mL(-1) of Cu(II) ion, respectively. The interference effect of some anions and cations was also tested. The method was applied for determination of copper in food, water and biological samples.

  12. Principles of biological adaptation of organisms in artificial ecosystems to changes of environmental factors

    Science.gov (United States)

    Somova, L. A.; Pechurkin, N. S.; Pisman, T. I.

    Studying material transformations and biotic cycling in artificial ecosystems (AES), we need to know the principles of biological adaptation of active organisms to change in the environment. Microorganisms in AES for water purification are the most active transforming organisms and consumers of the organic substances contained in wastes. Utilization of organic substances is directly connected with the energy fluxes used by AES. According to energy criteria, the energy fluxes used by a biological system tend to reach maximum values under stable conditions. Unutilized substrate concentration decreases as a result of biological adaptations. After a dramatic change in environmental factors, for example, after a sharp increase in the flow rate of organic substances, the biological system is not able to react quickly. The concentration of unutilized substrate increases and the energy flux used by the biological system decreases. The structure of the microbial community also changes, with a decrease in biological diversity. The efficiency of energy use by simple terrestrial ecosystems depends on the energetic intensity and interactions between plants and rhizospheric microorganisms.

  13. Determination of selenium in biological samples with an energy-dispersive X-ray fluorescence spectrometer.

    Science.gov (United States)

    Li, Xiaoli; Yu, Zhaoshui

    2016-05-01

    Selenium is both a nutrient and a toxin. Selenium-especially organic selenium-is a core component of human nutrition. Thus, it is very important to measure selenium in biological samples. The limited sensitivity of conventional XRF hampers its widespread use in biological samples. Here, we describe the use of high-energy (100kV, 600W) linearly polarized beam energy-dispersive X-Ray fluorescence spectroscopy (EDXRF) in tandem with a three-dimensional optics design to determine 0.1-5.1μgg(-1) levels of selenium in biological samples. The effects of various experimental parameters such as applied voltage, acquisition time, secondary target and various filters were thoroughly investigated. The detection limit of selenium in biological samples via high-energy (100kV, 600W) linearly polarized beam energy-dispersive X-ray fluorescence spectroscopy was decreased by one order of magnitude versus conventional XRF (Paltridge et al., 2012) and found to be 0.1μg/g. To the best of our knowledge, this is the first report to describe EDXRF measurements of Se in biological samples with important implications for the nutrition and analytical chemistry communities. PMID:26922394

  14. Topographic patterns of vascular disease: HOX proteins as determining factors?

    Institute of Scientific and Technical Information of China (English)

    Richard; P; Visconti; Alexander; Awgulewitsch

    2015-01-01

    Steadily increasing evidence supports the idea that genetic diversities in the vascular bed are, in addition to hemodynamic influences, a major contributing factor in determining region-specific cardiovascular disease susceptibility. Members of the phylogenetically highly conserved Hox gene family of developmental regulators have to be viewed as prime candidates for determining these regional genetic differences in the vasculature. During embryonic patterning, the regionally distinct and precisely choreographed expression patterns of HOX transcription factors are essential for the correct specification of positional identities. Apparently, these topographic patterns are to some degree retained in certain adult tissues, including the circulatory system. While an understanding of the functional significance of these localized Hox activities in adult blood vessels is only beginning to emerge, an argument can be made for a role of Hox genes in the maintenance of vessel wall homeostasis and functional integrity on the one hand, and in regulating the development and progression of regionally restricted vascular pathologies, on the other. Initial functional studies in animal models, as well as data from clinical studies provide some level of support for this view. The data suggest that putative genetic regulatory networks of Hox-dependent cardiovascular disease processes include genes of diverse functional categories(extracellular matrix remodeling, transmembrane signaling, cell cycle control, inflammatory response, transcriptional control, etc.), as potential targets in both vascular smooth muscle and endothelial cells, as well as cell populations residing in the adventitia.

  15. Teacher Related Factors Influencing Students' Enrollment in Biology Subject in Public Secondary Schools in Meru Central Sub County in Kenya

    Science.gov (United States)

    Kirima, Teresia Mugure; Kinyua, Susan Muthoni

    2016-01-01

    This study examined teacher related factors influencing students' enrollment in Biology subject in public secondary schools in Meru Central Sub County in Kenya. The study utilized the descriptive survey research design on a target population of 9,859 respondents consisting of 9,748 Biology students, 62 trained Biology teachers and 49 Heads of…

  16. On the accuracy of protein determination in large biological samples by prompt gamma neutron activation analysis

    International Nuclear Information System (INIS)

    A prompt gamma neutron activation analysis (PGNAA) facility has been developed for the determination of nitrogen and thus total protein in large volume biological samples or the whole body of small animals. In the present work, the accuracy of nitrogen determination by PGNAA in phantoms of known composition as well as in four raw ground meat samples of about 1 kg mass was examined. Dumas combustion and Kjeldahl techniques were also used for the assessment of nitrogen concentration in the meat samples. No statistically significant differences were found between the concentrations assessed by the three techniques. The results of this work demonstrate the applicability of PGNAA for the assessment of total protein in biological samples of 0.25-1.5 kg mass, such as a meat sample or the body of small animal even in vivo with an equivalent radiation dose of about 40 mSv

  17. Determination of 36Cl in biological shield concrete using pyrohydrolysis and liquid scintillation counting.

    Science.gov (United States)

    Itoh, Mitsuo; Watanabe, Kazuo; Hatakeyama, Mutsuo; Tachibana, Mitsuo

    2002-07-01

    A method for the determination of 36Cl in biological shield concrete of nuclear reactors was developed. Cl in the concrete sample was extracted quantitatively by pyrohydrolysis at 900 degrees C and recovered in Na2CO3 solution for subsequent measurement of 36Cl by liquid scintillation counting. WO3 was used as an accelerator in the pyrohydrolysis. The Cl extraction procedure was optimized by investigating experimental conditions with the use of ion chromatography and its recovery was evaluated by the analysis of the geochemical reference samples. The detection limit of 36Cl was 0.02 Bq g(-1) for a sample weight of 2 g. The relative standard deviation was 3-7% for the samples containing 0.5 Bq g(-1) levels of 36Cl. The method was applied to determine 36Cl in biological shield concrete of the Japan Power Demonstration Reactor. PMID:12173658

  18. METHOD FOR DETERMINING THE MAXIMUM ARRANGEMENT FACTOR OF FOOTWEAR PARTS

    Directory of Open Access Journals (Sweden)

    DRIŞCU Mariana

    2014-05-01

    Full Text Available By classic methodology, designing footwear is a very complex and laborious activity. That is because classic methodology requires many graphic executions using manual means, which consume a lot of the producer’s time. Moreover, the results of this classical methodology may contain many inaccuracies with the most unpleasant consequences for the footwear producer. Thus, the costumer that buys a footwear product by taking into consideration the characteristics written on the product (size, width can notice after a period that the product has flaws because of the inadequate design. In order to avoid this kind of situations, the strictest scientific criteria must be followed when one designs a footwear product. The decisive step in this way has been made some time ago, when, as a result of powerful technical development and massive implementation of electronical calculus systems and informatics, This paper presents a product software for determining all possible arrangements of a footwear product’s reference points, in order to automatically acquire the maximum arrangement factor. The user multiplies the pattern in order to find the economic arrangement for the reference points. In this purpose, the user must probe few arrangement variants, in the translation and rotate-translation system. The same process is used in establishing the arrangement factor for the two points of reference of the designed footwear product. After probing several variants of arrangement in the translation and rotation and translation systems, the maximum arrangement factors are chosen. This allows the user to estimate the material wastes.

  19. Biologic

    CERN Document Server

    Kauffman, L H

    2002-01-01

    In this paper we explore the boundary between biology and the study of formal systems (logic). In the end, we arrive at a summary formalism, a chapter in "boundary mathematics" where there are not only containers but also extainers ><, entities open to interaction and distinguishing the space that they are not. The boundary algebra of containers and extainers is to biologic what boolean algebra is to classical logic. We show how this formalism encompasses significant parts of the logic of DNA replication, the Dirac formalism for quantum mechanics, formalisms for protein folding and the basic structure of the Temperley Lieb algebra at the foundations of topological invariants of knots and links.

  20. Determination of captopril in pharmaceutical preparation and biological fluids using two- and three-way chemometrics methods

    Institute of Scientific and Technical Information of China (English)

    Nahid Ghasemi; Ali Niazi

    2007-01-01

    Spectrophotometric method has been developed for the direct quantitative determination of captopril in pharmaceutical preparation and biological fluids (human plasma and urine) samples. The method was accomplished based on parallel factor analysis (PARAFAC) and partial least squares (PLS). The study was carried out in the pH range from 2.0 to 12.8 and with a concentration from 0.70 to 61.50 μg mL-1 of captopril. Multivariate calibration models such as PLS at various pH and PARAFAC were elaborated from ultraviolet spectra deconvolution and captopril determination. The best models for this system were obtained with PARAFAC and PLS at pH 2.0. The applications of the method for determination of real samples were evaluated by analysis of captopril in pharmaceutical preparations and biological fluids with satisfactory results. The accuracy of the method, evaluated through the RMSEP, was 0.5801 for captopril with best calibration curve by PARAFAC and 0.6168 for captopril with PLS at pH 2.0 model.

  1. Determination of biological transport of oxygen-15 and carbon-11 generated in rats

    International Nuclear Information System (INIS)

    The distribution of induced 15O and 11C activity in live and dead rats was determined following local irradiation with a 32 MeV proton beam. Results indicate that rapid biological redistribution of some of the induced activity occurs within a minute following irradiation. Sufficient activity remains, bound in the intracellular water, to define the proton beam in tissue. Thus, mapping of the induced 15O activity proves to be a valid means of beam localization

  2. Voltammetric and amperometric determination of biologically active organic compounds using various types of silver amalgam electrodes

    OpenAIRE

    Barek, Jiří; Fischer, Jan; Moreira, Josino C.; Wang, Joseph

    2014-01-01

    In this paper, possibilities of various types of silver amalgam electrodes for determination of micromolar and submicromolar concentrations of various electrochemically reducible biologically active organic compounds are reviewed. Attention is paid to the use of polished and mercury meniscus modified silver solid amalgam electrodes, silver amalgam paste electrodes both with and without pasting liquids, single crystal silver amalgam electrodes, composite silver amalgam electrodes, and porous s...

  3. Optimization and validation of spectrophotometric methods for determination of finasteride in dosage and biological forms

    OpenAIRE

    Amin, Alaa S.; Kassem, Mohammed A.

    2012-01-01

    Aim and Background: Three simple, accurate and sensitive spectrophotometric methods for the determination of finasteride in pure, dosage and biological forms, and in the presence of its oxidative degradates were developed. Materials and Methods: These methods are indirect, involve the addition of excess oxidant potassium permanganate for method A; cerric sulfate [Ce(SO4)2] for methods B; and N-bromosuccinimide (NBS) for method C of known concentration in acid medium to finasteride, and the de...

  4. Sex determination meltdown upon biological control introduction of the parasitoid Cotesia rubecula?

    OpenAIRE

    Boer; Kuijper, B.; Heimpel, G.E.; Beukeboom, L. W.

    2012-01-01

    Natural enemies may go through genetic bottlenecks during the process of biological control introductions. Such bottlenecks are expected to be particularly detrimental in parasitoid Hymenoptera that exhibit complementary sex determination (CSD). CSD is associated with a severe form of inbreeding depression because homozygosity at one or multiple sex loci leads to the production of diploid males that are typically unviable or sterile. We observed that diploid males occur at a relatively high r...

  5. Analytic determination of the activation of essential and toxic trace elements in biological material

    International Nuclear Information System (INIS)

    A neutron activation-analysis technique for the multielement determination in biological material was developed. The individual steps of this procedure comprise radiochemical and also instrumental analytic techniques. After radiochemical separation 34 elements can be determined, after only instrumental procedures 26 elements can be detected in biological material. The radiochemical analysis of 34 elements lasts 4 days. Tracer investigations on the radionuclide retention of the anorganic separators HAP, TiP and ZP in 9N aqueous HNO3 solution indicated that apart from Na-24, K-42 and P-32 the radionuclides Cs-134, Rb-86 and Se-75 are almost quantitatively adsorbed at the separators. For the remaining investigated radionuclides different but well-reproducible retention values resulted. The pH-value only slightly influences the extent of the radionuclide retention. Kinetic investigations on the radiochemical precipitation of some radionuclides on Cu and Cu(Hg)sub(x) were carried out. The depositing of the radionuclides Ag-110m, Hg-203 and Se-75 at 00C and room temperature on Cu(Hg)sub(x) and Cu foil is a first order reaction. The half-life periods and the velocity constants of the depositing on Cu and Cu(Hg)sub(x) were determined for the investigated radionuclides in dependency of the temperature. The technique was examined by means of international biological multielement standards of known element combinations. The realisation of ring tests for the multielement determination in potatoe and milk powder showed that this method provides precise results. The applicability of the radiochemical method was confirmed by the simultaneous determination of 25 elements in overall nutrition samples. The instrumental technique was applied for the multielement determination in human hair (of the head) and in river water. (orig./MG)

  6. Mass determination based on electron scattering in electron probe X-ray microanalysis of thin biological specimens

    International Nuclear Information System (INIS)

    This thesis describes the development of a method for mass determination of thin biological objects by quantitative electron microscopy. The practical realization of the mass determination consists of photographical recording with subsequent densitometry. (Auth.)

  7. The use of a single technique for the separation and determination of actinides in biological materials

    International Nuclear Information System (INIS)

    For the radiotoxicological survey of workers exposed to different types of alpha-emitting contaminants, a procedure was developed which permits the estimate of Th, Pa, U, Np, Pu, Am and Cm in biological samples with a single technique. The radionuclides are extracted on a column by tri-n-octylphosphine oxide and separated by elution at different pH values. Afterwards, the quantitative determinations are done by physical methods (alpha counting or spectrometry). In the case of an accident it is possible to use a simplification of the procedure (extraction in a beaker) for checks. A procedure for the rapid determination of actinides in faeces and in nasal secretions is described

  8. Biological Variations of Lupus Anticoagulant, Antithrombin, Protein C, Protein S, and von Willebrand Factor Assays.

    Science.gov (United States)

    Shou, Weiling; Chen, Qian; Wu, Wei; Cui, Wei

    2016-02-01

    The results of lupus anticoagulant (LA), antithrombin (AT), protein C (PC), and protein S (PS) testing, and the values of von Willebrand factor antigen (VWF:Ag) are important in diagnosis and therapeutic monitoring of thrombosis and hemostasis diseases. Till now, no published study has focused on the biological variations in LA testing, and only a few studies have examined the biological variations of AT, PC, PS, and VWF:Ag. With the latest fully automated instruments and improved reagents, the analytical, within-subject, and between-subject biological variations were estimated for these five coagulant parameters in a cohort of 25 apparently healthy subjects. Blood specimens were collected at 8:00 am, 12:00 pm, and 4:00 pm on days 1, 3, and 5. The analytical biological variation (CV(A)) values of all the parameters were less than 3%. The within-subject biological variation (CV(W)) and between-subject biological variation (CV(G)) values of the LA normalized ratio were 4.64 and 6.83%, respectively. No significant differences were observed in the intraday and interday biological variations of LA tests, or in AT, PC, PS, and VWF:Ag values. Additionally, the utility of the conventional population-based reference intervals of the five coagulation parameters was evaluated by the index of individuality, and data on CV(W) and CV(A) were used to calculate the reference change value to identify the significance of changes in serial results from the same individual. PMID:26516946

  9. Determination of macrolides in biological matrices by high-performance liquid chromatography with electrochemical detection.

    Science.gov (United States)

    Kees, F; Spangler, S; Wellenhofer, M

    1998-07-01

    A liquid chromatographic method for the determination of macrolide antibiotics is described using a cyanopropyl column which proved to be as efficient or superior to the normally used apolar reversed-phase columns. The recovery of the macrolides from water and plasma was 80-90%. Using 0.5 ml of plasma, 30 ng/ml of clarithromycin, 50 ng/ml of roxithromycin and 10 ng/ml of azithromycin could be determined with acceptable precision and accuracy. The method has been employed in pharmacokinetic studies in humans for the determination of roxithromycin, clarithromycin and azithromycin in plasma, serum and other biological matrices. The particular selectivity of the cyanopropyl phase may also allow the simultaneous determination of erythromycin and its prodrug esters. PMID:9691325

  10. Some environmental and biological factors influencing the activity of entomopathogenic Bacillus on mosquito larvae in Brazil

    Directory of Open Access Journals (Sweden)

    R. A. G. B Consoli

    1995-02-01

    Full Text Available The influence of environmental and biological factors on the efficacy of Bacillus thuringiensis serovar israelensis and B. sphaericus as mosquito larvicides are reviewed. The importance of strain dependence, cultivating media/methods, mosquito species/specificity, formulations and their relation to mosquito feeding habits, as well as temperature, solar exposure, larval density and concomitant presence of other aquatic organisms are addressed with reference to the present status of knowledge in Brazil.

  11. Influence of physical and chemical factors on biological leaching process of copper from printed circuit boards

    OpenAIRE

    Willner, J

    2013-01-01

    The article presents the results of the research regarding the biological leaching of this metal from electronic wastes components in the form of printed circuit boards. The purpose of the study was to evaluate the influence of some physical and chemical factors (e.g. pH, oxidation-reduction potential) on bioleaching process and efficiency of copper transfer from solid phase into solution. Bioleaching experiments were carried out with pure cultures of Acidithiobacillus ferrooxidans. The obtai...

  12. Factors determining the outcome of children hospitalized with severe pneumonia

    Directory of Open Access Journals (Sweden)

    Broor Shobha

    2009-02-01

    Full Text Available Abstract Background Pneumonia is one of the leading causes of morbidity and mortality in under fives. We carried out a comprehensive study to identify factors influencing both mortality and morbidity for children less than 5 years of age hospitalized with severe pneumonia. Methods 200 hospitalized children aged 2–60 months with World Health Organization (WHO defined severe pneumonia were enrolled in the study. The children were managed using a standard protocol. They were closely followed up for need for change in antibiotics, prolonged hospital stay, need for mechanical ventilation and mortality. Data on the factors influencing the outcome were collected. Results Of 200 children enrolled in the study, 113 (56.5% needed a change in antibiotics, 102 (51% stayed for more than 5 days in the hospital, 41 (20.5% needed mechanical ventilation and 21 (10.5% died. On multivariate analysis, lack of exclusive breastfeeding [RR (95%CI 2.63 (2.16–2.86], overcrowding [RR (95%CI 1.94 (1.35–2.38] and an abnormal chest x-ray [RR (95%CI 2.29 (1.22–3.44] were associated with the need for change of antibiotics. Lack of exclusive breastfeeding [RR (95%CI 2.56 (2.0–2.93], overcrowding [RR (95%CI 2.59 (1.78–3.23] and an abnormal chest x-ray [RR (95%CI 2.99 (1.65–4.38] were identified as determinants for prolonged hospital stay. Head nodding [RR (95%CI 8.34 (2.71–12.77], altered sensorium [RR (95%CI 5.44 (1.34–17.56], abnormal leukocyte counts [RR (95%CI 5.85(1.36–17.14] and pallor [RR (95%C 10.88 (2.95–20.40] were associated with mortality. Head nodding (RR (95% CI 4.73 (1.50–6.36] and cyanosis (RR (95%CI 5.06 (1.80–11.34] were the determining factors for mechanical ventilation. In radiographically confirmed pneumonia, the determining factors for change of antibiotics were: lack of exclusive breast feeding [RR (95% CI 2.05 (1.69–2.2] and low birth weight [RR (95% CI 1.59 (1.1–1.89]. For prolonged hospital stay, the factors identified

  13. Progress of transcription factor Twist expression in breast cancer and its biological effect

    Institute of Scientific and Technical Information of China (English)

    Tian Qian

    2016-01-01

    Breast cancer is the most common malignant tumor in women and the pathogenesis is not fully elucidated. Proliferation, invasion, epithelial-mesenchymal transition and angiogenesis are the links closely related to the occurrence and development of breast cancer. Twist is a type of basic helix-loop-helix transcription factor that can affect cell proliferation and invasion process, epithelial-mesenchymal transition process and angiogenesis process through regulating the transcription of downstream target genes. In the research, the study of transcription factor Twist expression in breast cancer and its biological effect is reviewed.

  14. Biological psychological and social determinants of old age: Bio-psycho-social aspects of human aging

    Directory of Open Access Journals (Sweden)

    Małgorzata Dziechciaż

    2014-11-01

    Full Text Available Biological psychological and social determinants of old age: Bio-psycho-social aspects of human aging. The aging of humans is a physiological and dynamic process ongoing with time. In accordance with most gerontologists’ assertions it starts in the fourth decade of life and leads to death. The process of human aging is complex and individualized, occurs in the biological, psychological and social sphere. Biological aging is characterized by progressive age-changes in metabolism and physicochemical properties of cells, leading to impaired self-regulation, regeneration, and to structural changes and functional tissues and organs. It is a natural and irreversible process which can run as successful aging, typical or pathological. Biological changes that occur with age in the human body affect mood, attitude to the environment, physical condition and social activity, and designate the place of seniors in the family and society. Psychical ageing refers to human awareness and his adaptability to the ageing process. Among adaptation attitudes we can differentiate: constructive, dependence, hostile towards others and towards self attitudes. With progressed age, difficulties with adjustment to the new situation are increasing, adverse changes in the cognitive and intellectual sphere take place, perception process involutes, perceived sensations and information received is lowered, and thinking processes change. Social ageing is limited to the role of an old person is culturally conditioned and may change as customs change. Social ageing refers to how a human being perceives the ageing process and how society sees it.

  15. A systems biological approach to identify key transcription factors and their genomic neighborhoods in human sarcomas

    Institute of Scientific and Technical Information of China (English)

    Antti Ylip(a)(a); Olli Yli-Harja; Wei Zhang; Matti Nykter

    2011-01-01

    Identification of genetic signatures is the main objective for many computational oncology studies. The signature usually consists of numerous genes that are differentially expressed between two clinically distinct groups of samples, such as tumor subtypes. Prospectively, many signatures have been found to generalize poorly to other datasets and, thus, have rarely been accepted into clinical use. Recognizing the limited success of traditionally generated signatures, we developed a systems biology-based framework for robust identification of key transcription factors and their genomic regulatory neighborhoods. Application of the framework to study the differences between gastrointestinal stromal tumor (GIST) and leiomyosarcoma (LMS) resulted in the identification of nine transcription factors (SRF, NKX2-5, CCDC6, LEF1, VDR, ZNF250, TRIM63, MAF, and MYC). Functional annotations of the obtained neighborhoods identified the biological processes which the key transcription factors regulate differently between the tumor types. Analyzing the differences in the expression patterns using our approach resulted in a more robust genetic signature and more biological insight into the diseases compared to a traditional genetic signature.

  16. Molecular subtype analysis determines the association of advanced breast cancer in Egypt with favorable biology

    Directory of Open Access Journals (Sweden)

    DuQuette Rachelle A

    2011-09-01

    Full Text Available Abstract Background Prognostic markers and molecular breast cancer subtypes reflect underlying biological tumor behavior and are important for patient management. Compared to Western countries, women in North Africa are less likely to be prognosticated and treated based on well-characterized markers such as the estrogen receptor (ER, progesterone receptor (PR and Her2. We conducted this study to determine the prevalence of breast cancer molecular subtypes in the North African country of Egypt as a measure of underlying biological characteristics driving tumor manifestations. Methods To determine molecular subtypes we characterized over 200 tumor specimens obtained from Egypt by performing ER, PR, Her2, CK5/6, EGFR and Ki67 immunohistochemistry. Results Our study demonstrated that the Luminal A subtype, associated with favorable prognosis, was found in nearly 45% of cases examined. However, the basal-like subtype, associated with poor prognosis, was found in 11% of cases. These findings are in sharp contrast to other parts of Africa in which the basal-like subtype is over-represented. Conclusions Egyptians appear to have favorable underlying biology, albeit having advanced disease at diagnosis. These data suggest that Egyptians would largely profit from early detection of their disease. Intervention at the public health level, including education on the benefits of early detection is necessary and would likely have tremendous impact on breast cancer outcome in Egypt.

  17. Application of source-receptor models to determine source areas of biological components (pollen and butterflies

    Directory of Open Access Journals (Sweden)

    M. Alarcón

    2010-01-01

    Full Text Available The source-receptor models allow the establishment of relationships between a receptor point (sampling point and the probable source areas (regions of emission through the association of concentration values at the receptor point with the corresponding atmospheric back-trajectories, and, together with other techniques, to interpret transport phenomena on a synoptic scale. These models are generally used in air pollution studies to determine the areas of origin of chemical compounds measured at a sampling point, and thus be able to target actions to reduce pollutants. However, until now, few studies have applied these types of models to describe the source areas of biological organisms. In Catalonia there are very complete records of pollen (data from the Xarxa Aerobiològica de Catalunya, Aerobiology Network of Catalonia and butterflies (data from the Catalan Butterfly Monitoring Scheme, a biological material that is also liable to be transported long distances and whose areas of origin could be interesting to know. This work presents the results of the use of the Seibert et al. model applied to the study of the source regions of: (1 certain pollen of an allergic nature, observed in Catalonia and the Canary Islands, and (2 the migratory butterfly Vanessa cardui, observed in Catalonia. Based on the results obtained we can corroborate the suitability of these models to determine the area of origin of several species, both chemical and biological, therefore expanding the possibilities of applying the original model to the wider field of Aerobiology.

  18. COMPLEMENTARY SEX DETERMINATION IN HYMENOPTERAN PARASITOIDS AND ITS IMPLICATIONS FOR BIOLOGICAL CONTROL

    Institute of Scientific and Technical Information of China (English)

    WUZhishan; KeithR.Hopper; PaulJ.Ode; RogerW.Fuester; CHENJia-hua; GeorgeE.Heimpel

    2003-01-01

    In haplodiploid Hymenoptera, unfertilized eggs produce haploid males while fertilized eggs lead to diploid females under most circumstances. Diploid males can also be produced from fertilization under a system of sex determination known as complementary sex determination (CSD). Under single-locus CSD, sex is determined by multiple alleles at a single sex locus. Individuals heterozygous at the sex locus are female while hemizygous and homozygous individuals develop as haploid and diploid males, respectively. In multiple-locus CSD, two or more loci, each with two or more alleles, determine sex. Diploid individuals are female if one or more sex loci are het-erozygous, while a diploid is male only if homozygous at all sex loci. Diploid males are known to occur in 43 hym-enopteran species and single-locus CSD has been demonstrated in 22 of these species. Diploid males are either developmentally inviable or sterile, so their production constitutes a genetic load. Because diploid male production is more likely under inbreeding, CSD is a form of inbreeding depression. It is crucial to preserve the diversity of sex alleles and reduce the loss of genetic variation in biological control. In the parasitoid species with single-locus CSD, certain precautionary procedures can prevent negative effects of single-locus CSD on biological control.

  19. Cytogenetic method of determining effect of threshold values of anthropogenic factors on the plant and animal genome

    International Nuclear Information System (INIS)

    The use of nucleolar characteristics to access the action of physical and chemical factors on living objects is a promising trend in the creation of new and highly sensitive biological tests. The advantages of this process are that the effect of the threshold values of the anthropogenic factors is recorded as a change in functional activity of the cell genome and not as the restructuring of the karyotype. The aim of this research was to test a cytogenetic method of determining the modifying action of various factors on the plant and animal genome, based on analysis of quantitative characteristics of the nucleoli and to extend its use to different groups of organisms

  20. Determination of acrylamide in local and commercial cultivar of potatoes from biological farm.

    Science.gov (United States)

    Marchettini, Nadia; Focardi, Silvia; Guarnieri, Massimo; Guerranti, Cristiana; Perra, Guido

    2013-02-15

    This paper reports the results of a preliminary study on the characterization of parameters influencing formation of acrylamide in fried potatoes, from biological cultivation. The formation of acrylamide was investigated in relation to frying in biological extra virgin olive oil and commercial seed oil. Three different cultivars (Rossa di Colfiorito, Quarantina bianca genovese and Kennebec) were chosen. Asparagine, glucose, fructose and sucrose concentrations were determined in potato slice before frying, while acrylamide content was analysed by LC-ESI-MS/MS in the slices fried in seed and extra virgin olive oil. The Kennebec cultivar showed differences in its potential for acrylamide formation, which was primarily related to its relatively high asparagine and reducing sugars contents, respect the other local cultivars (particulary Quarantina). Values of acrylamide below detection limit (LOD) were found in Quarantina bianca genovese cultivar samples fried in extra virgin olive oil and peanuts seed oil and higher in peanuts seed oil fried potatoes of Kennebec cultivar.

  1. Krüppel-like family of transcription factors: an emerging new frontier in fat biology

    Directory of Open Access Journals (Sweden)

    Christopher W. Brey, Mark P. Nelder, Tiruneh Hailemariam, Randy Gaugler, Sarwar Hashmi

    2009-01-01

    Full Text Available In mammals, adipose tissue stores energy in the form of fat. The ability to regulate fat storage is essential for the growth, development and reproduction of most animals, thus any abnormalities caused by excess fat accumulation can result in pathological conditions which are linked to several interrelated diseases, such as cardiovascular diseases, diabetes, and obesity. In recent years significant effort has been applied to understand basic mechanism of fat accumulation in mammalian system. Work in mouse has shown that the family of Krüppel-like factors (KLFs, a conserved and important class of transcription factors, regulates adipocyte differentiation in mammals. However, how fat storage is coordinated in response to positive and negative feedback signals is still poorly understood. To address mechanisms underlying fat storage we have studied two Caenorhabditis elegans KLFs and demonstrate that both worm klfs are key regulators of fat metabolism in C. elegans. These results provide the first in vivo evidence supporting essential regulatory roles for KLFs in fat metabolism in C. elegans and shed light on the human counterpart in disease-gene association. This finding allows us to pursue a more comprehensive approach to understand fat biology and provides an opportunity to learn about the cascade of events that regulate KLF activation, repression and interaction with other factors in exerting its biological function at an organismal level. In this review, we provide an overview of the most current information on the key regulatory components in fat biology, synthesize the diverse literature, pose new questions, and propose a new model organism for understanding fat biology using KLFs as the central theme.

  2. Determination of rhenium in biological and environmental samples by radiochemical neutron activation analysis

    International Nuclear Information System (INIS)

    Radiochemical neutron activation procedures using liquid-liquid extraction with tetraphenylarsonium chloride in chloroform from 1 M HCl and solid extraction with ALIQUAT 336 incorporated in a polyacrylonitrile binding matrix from 0.1 M HCl were developed for accurate determination of rhenium in biological and environmental samples at the sub-ng.g-1 level. Concentrations of Re in the range of 0.1 to 2.4 ng.g-1 were determined in several botanical reference materials (RM), while in a RM of road dust a value of approx. 10 ng.g-1 was found. Significantly elevated values of Re, up to 90 ng.g-1, were found in seaweed (brown algae). Results for Re in the brown algae Fucus vesiculosus in which elevated 99Tc values had previously been determined suggest possible competition between Re and Tc in the accumulation process. (author)

  3. Predictable factors for lymph node metastasis in early gastric cancer analysis of clinicopathologic factors and biological markers.

    Science.gov (United States)

    Wang, Yi-Wei; Zhu, Mei-Ling; Wang, Rui-Fen; Xue, Wen-Ji; Zhu, Xue-Ru; Wang, Li-Feng; Zheng, Lei-Zhen

    2016-07-01

    Predicting lymph node metastasis (LNM) accurately is very important to decide treatment strategies preoperatively. The aim of this study was to explore risk factors that predict the presence of LNM in early gastric cancer (EGC). A total of 230 patients with EGC who underwent curative gastrectomy with lymph adenectomy at Xinhua Hospital from January 2006 to July 2014 were retrospectively reviewed. We studied the relationship between clinicopathological factors, biological markers (p53, ki67, nm23, vascular endothelial growth factor (VEGF), epidermal growth factor receptor (EGFR), E-cadherin (E-cad), beta-catenin (b-catenin), glutathione S-transferase (GST), and topoisomerase II (Topo II)), and LNM of EGC patients by chi-square test and logistic regression analysis. Meta-analyses were further conducted to review the effects of the proteins (P53, ki67, E-cad, and b-catenin) on LNM in ECG patients. LNM was detected in 42 (18.3 %) of 230 patients. Incidences of LNM was distinct in different tumor size (p = 0.044), depth of submucosal invasion (p validation in single large studies. PMID:26733174

  4. Biological markers as predictive factors of response to neoadjuvant taxanes and anthracycline chemotherapy in breast carcinoma

    Institute of Scientific and Technical Information of China (English)

    ZHOU Bo; YANG De-qi; XIE Fei

    2008-01-01

    Background Neoadjuvant chemotherapy provides an excellent model for evaluation of potential predictive factors.The objective of this study was to evaluate the predictive value of different biological factors in breast cancer patients treated with neoadjuvant taxane and anthracycline chemotherapy.Methods One hundred and thirty-five patients treated with 4 cycles of neoadjuvant taxanes and anthracycline were included in this retrospective study.Using pretreatment biopsy materials,immunohistochemical studies were performed for estrogen receptor(ER),progesterone receptor(PgR),HER-2,Ki-67 and p53 protein expression.The associations among biological markers and clinical and pathological complete response (pCR)were analyzed.Results The overall clinical response was 86%,including 33%clinical complete response(cCR)and 53%clinical partial response.The pCR was iust 17%.In the univariate analysis,only HER-2 overexpression was predictive of cCR to neoadjuvant chemotherapy(P=0.018).No significant associations between other biological factors and cCR were found.Absence of ER,PgR expression and overexpression of HER-2 were predictive of the pCR(P=0.002,0.001,0.01,respectively).Ki-67 and p53 failed to show an association with pCR.In multivariate analysis,overexpression of HER-2remained as an independent variable in predicting the cCR(P=0.021).However,negative ER was the only parameter that maintained statistical significance in predicting the pCR(P=0.001).Conclusions Patients with overexoression of HER-2 and negative hormonal receptor status are much more likely to respond to neoadjuvant taxane and anthracycline chemotherapy than those with the opposite characte ristics.These factors could serve as predictive markers for this regimen.

  5. Determination of Breastfeeding Behaviors of Mothers and Influencing Factors

    Directory of Open Access Journals (Sweden)

    Aygul Akyuz

    2007-10-01

    Full Text Available This study is a descriptive research which was planned to determine the factors related to beginning and maintaining the breastfeeding of the mothers. This research was conducted with the mothers who applied to the The Healthy Child Department in Pediatrics Clinic at Gulhane Medical Millitary Academy (GMMA. The women who applied to this department constituted the population of the study (N=750, and the women who volunteered to join the study between April and June constituted the sampling (n=120. In the result of this study, the most of the women planned to feed their babies with breast milk, and for their choice of preferring the breast milk, they thought that breast milk is the best nutrient for their babies, and keeping their babies from the illnesses. It was found that the half of the mothers who had vaginal birth fed their babies with the breast milk in an early one hour. Seventy-nine point two percentages of the mothers pointed out giving no meals before feeding with breast milk, and the others generally fed their babies with infant food and liquid with sugar. In this study, it was determined that breastfeeding is still common among the mothers, and most of the babies are fed with the breast milk for several times. However the babies are fed with the milk for a long time, the mothers still need education and training programme about the subjects like initial breastfeeding time, giving the liquid and infant food, only not giving the breast milk and start to feed with infant food early or later. [TAF Prev Med Bull. 2007; 6(5: 331-335

  6. Determination of Breastfeeding Behaviors of Mothers and Influencing Factors

    Directory of Open Access Journals (Sweden)

    Aygul Akyuz

    2007-10-01

    Full Text Available This study is a descriptive research which was planned to determine the factors related to beginning and maintaining the breastfeeding of the mothers. This research was conducted with the mothers who applied to the The Healthy Child Department in Pediatrics Clinic at Gulhane Medical Millitary Academy (GMMA. The women who applied to this department constituted the population of the study (N=750, and the women who volunteered to join the study between April and June constituted the sampling (n=120. In the result of this study, the most of the women planned to feed their babies with breast milk, and for their choice of preferring the breast milk, they thought that breast milk is the best nutrient for their babies, and keeping their babies from the illnesses. It was found that the half of the mothers who had vaginal birth fed their babies with the breast milk in an early one hour. Seventy-nine point two percentages of the mothers pointed out giving no meals before feeding with breast milk, and the others generally fed their babies with infant food and liquid with sugar. In this study, it was determined that breastfeeding is still common among the mothers, and most of the babies are fed with the breast milk for several times. However the babies are fed with the milk for a long time, the mothers still need education and training programme about the subjects like initial breastfeeding time, giving the liquid and infant food, only not giving the breast milk and start to feed with infant food early or later. [TAF Prev Med Bull 2007; 6(5.000: 331-335

  7. Evaluation of Botanical Reference Materials for the Determination of Vanadium in Biological Samples

    DEFF Research Database (Denmark)

    Heydorn, Kaj; Damsgaard, Else

    1982-01-01

    Three botanical reference materials prepared by the National Bureau of Standards have been studied by neutron activation analysis to evaluate their suitability with respect to the determination of vanadium in biological samples. Various decomposition methods were applied in connection with chemic....... A reference value of 1.15 mg/kg of this material is recommended, based on results from 3 different methods. All three materials are preferable to SRM 1571 Orchard Leaves, while Bowen's Kale remains the material of choice because of its lower concentration....

  8. Medical and biologic factors of speech and language development in children (part 2

    Directory of Open Access Journals (Sweden)

    Chernov D.N.

    2015-03-01

    Full Text Available The recent data shows that medico-biological aspects of the study of speech and language development in children should be expanded to include an analysis of various socio-cultural factors as the problem requires an interdisciplinary approach. The review stresses the necessity of methodological approach to study of bio- socio-cultural conditions of emerging speech and language abilities in ontogenesis. Psycho-pedagogical aspect involves: informing parents about the medical and biological aspects of speech and language development in childhood; the active involvement of parents in the remedial and preventive activities carried out by specialists; activities to improve the quality and quantity of child-parent interaction depending on the severity and nature of deviations in child speech and language development.

  9. Determination of Biological Treatability Processes of Textile Wastewater and Implementation of a Fuzzy Logic Model

    Directory of Open Access Journals (Sweden)

    Harun Akif Kabuk

    2015-01-01

    Full Text Available This study investigated the biological treatability of textile wastewater. For this purpose, a membrane bioreactor (MBR was utilized for biological treatment after the ozonation process. Due to the refractory organic contents of textile wastewater that has a low biodegradability capacity, ozonation was implemented as an advanced oxidation process prior to the MBR system to increase the biodegradability of the wastewater. Textile wastewater, oxidized by ozonation, was fed to the MBR at different hydraulic retention times (HRT. During the process, color, chemical oxygen demand (COD, and biochemical oxygen demand (BOD removal efficiencies were monitored for 24-hour, 12-hour, 6-hour, and 3-hour retention times. Under these conditions, 94% color, 65% COD, and 55% BOD removal efficiencies were obtained in the MBR system. The experimental outputs were modeled with multiple linear regressions (MLR and fuzzy logic. MLR results suggested that color removal is more related to COD removal relative to BOD removal. A surface map of this issue was prepared with a fuzzy logic model. Furthermore, fuzzy logic was employed to the whole modeling of the biological system treatment. Determination coefficients for COD, BOD, and color removal efficiencies were 0.96, 0.97, and 0.92, respectively.

  10. Correlation of high {sup 18}F-FDG uptake to clinical, pathological and biological prognostic factors in breast cancer

    Energy Technology Data Exchange (ETDEWEB)

    Groheux, David; Moretti, Jean-Luc; Hindie, Elif [Department of Nuclear Medicine, Saint-Louis Hospital,Assistance publique Hopitaux de Paris, Paris Cedex 10 (France); IUH, Doctoral School, University of Paris VII, Paris (France); Giacchetti, Sylvie; Espie, Marc; Hamy, Anne-Sophie; Cuvier, Caroline [Breast Diseases Unit, Saint-Louis Hospital, Department of Medical Oncology, Paris (France); Porcher, Raphael [Saint-Louis Hospital, Department of Biostatistics and Medical Information, Paris (France); Lehmann-Che, Jacqueline [Saint-Louis Hospital, Department of Biochemistry, Paris (France); Roquancourt, Anne de [Saint-Louis Hospital, Department of Pathology, Paris (France); Vercellino, Laetitia [Department of Nuclear Medicine, Saint-Louis Hospital, Assistance publique Hopitaux de Paris, Paris Cedex 10 (France)

    2011-03-15

    The aim of this study was to determine the impact of the main clinicopathological and biological prognostic factors of breast cancer on {sup 18}F-fluorodeoxyglucose (FDG) uptake. Only women with tumours larger than 20 mm (T2-T4) were included in order to minimize bias of partial volume effect. In this prospective study, 132 consecutive women received FDG PET/CT imaging before starting neoadjuvant chemotherapy. Maximum standardized uptake values (SUV{sub max}) were compared to tumour characteristics as assessed on core biopsy. There was no influence of T and N stage on SUV. Invasive ductal carcinoma showed higher SUV than lobular carcinoma. However, the highest uptake was found for metaplastic tumours, representing 5% of patients in this series. Several biological features usually considered as bad prognostic factors were associated with an increase in FDG uptake: the median of SUV{sub max} was 9.7 for grade 3 tumours vs 4.8 for the lower grades (p < 0.0001); negativity for oestrogen receptors (ER) was associated with higher SUV (ER+ SUV = 5.5; ER- SUV = 7.6; p = 0.003); triple-negative tumours (oestrogen and progesterone receptor negative, no overexpression of c-erbB-2) had an SUV of 9.2 vs 5.8 for all others (p = 0005); p53 mutated tumours also had significantly higher SUV (7.8 vs 5.0; p < 0.0001). Overexpression of c-erbB-2 had no effect on the SUV value. Knowledge of the factors influencing uptake is important when interpreting FDG PET/CT scans. Also, findings that FDG uptake is highest in those patients with poor prognostic features (high grade, hormone receptor negativity, triple negativity, metaplastic tumours) is helpful to determine who are the best candidates for baseline staging. (orig.)

  11. Research Advances in Interplay of Bursaphelenchus xylophilus and Other Key Biological Factors Related to Pine Wilt Disease

    Institute of Scientific and Technical Information of China (English)

    LIU Huimin; NING Shaohua; LIANG Jun; LU Quan

    2006-01-01

    The paper separately discusses interplay of pine wood nematode and several key biological factors related to pine wilt disease, such as host trees, insect vectors, fungi, symbiotic bacteria, and natural enemy acarid, etc. By virtue of so much complicated interplay among the biological factors related to pine wilt disease which is different from other forest disease, it also points out that the further researches about pine wilt disease should focus on interplay mechanism of key biological factors to discover pathogenic mechanism, and simple and quick inspection and quarantine methods.

  12. Identification of biological and environmental risk factors for language delay: The Let's Talk STEPS study.

    Science.gov (United States)

    Korpilahti, Pirjo; Kaljonen, Anne; Jansson-Verkasalo, Eira

    2016-02-01

    The aim of this population-based study was to identify demographic factors for language delays at an early age. The risk analysis covered 11 biological and 8 environmental factors. The mothers' concerns regarding language development were also examined. A total of 226 children from a Finnish cohort study were invited to participate in language assessments at 36 months. The test results for word finding and language comprehension were compared with parental questionnaires about children's vocabulary at 13 and 24 months. Regression analysis revealed that the father's social class (t=-2.79, p=0.006) and working full time (t=-2.86, p=0.005) significantly predicted children's language delay. In addition, language comprehension was significantly predicted by the mother's social class (t=-2.06, p=0.041) and by gender, with an advantage to girls (t=-2.71, p=0.008). Vocabulary at 24 months was a powerful predictor for lexical development (t=4.58, pparents needed special education during school years. At the population-level, gender was the most powerful biological factor in predicting language delays. Similarly, both parents' social status had predictive value for the child's language development. In addition, it was found that the mother's concern about her child's slow language acquisition should be taken into account when making decisions regarding special support. PMID:26700576

  13. Selection of models for the analysis of risk-factor trees: leveraging biological knowledge to mine large sets of risk factors with application to microbiome data

    OpenAIRE

    Zhang, Qunyuan; Abel, Haley; Wells, Alan; Lenzini, Petra; Gomez, Felicia; Province, Michael A; Templeton, Alan A.; Weinstock, George M.; Salzman, Nita H.; Borecki, Ingrid B.

    2015-01-01

    Motivation: Establishment of a statistical association between microbiome features and clinical outcomes is of growing interest because of the potential for yielding insights into biological mechanisms and pathogenesis. Extracting microbiome features that are relevant for a disease is challenging and existing variable selection methods are limited due to large number of risk factor variables from microbiome sequence data and their complex biological structure.

  14. Analytical Strategies for the Determination of Norepinephrine Reuptake Inhibitors in Pharmaceutical Formulations and Biological Fluids.

    Science.gov (United States)

    Saka, Cafer

    2016-01-01

    Norepinephrine reuptake inhibitors (NRIs) are a class of antidepressant drugs that act as reuptake inhibitors for the neurotransmitters norepinephrine and epinephrine. The present review provides an account of analytical methods published in recent years for the determination of NRI drugs. NRIs are atomoxetine, reboxetine, viloxazine and maprotiline. NRIs with less activity at other sites are mazindol, bupropion, tapentadol, and teniloxazine. This review focuses on the analytical methods including chromatographic, spectrophotometric, electroanalytical, and electrophoresis techniques for NRI analysis from pharmaceutical formulations and biological samples. Among all of the published methods, liquid chromatography with UV-vis or MS-MS detection is the most popular technique. The most the common sample preparation techniques in the analytical methods for NRIs include liquid-liquid extraction and solid-phase extraction. Besides the analytical methods for single components, some of the simultaneous determinations are also included in this review. PMID:26857446

  15. Enzymatic determination of carbon-14 labeled L-alanine in biological samples

    International Nuclear Information System (INIS)

    A method for determination of L-alanine-specific radioactivity in biological samples is presented. This method is based on the specific enzymatic transformation of L-alanine to pyruvic acid hydrazone catalyzed by the enzyme L-alanine dehydrogenase, formation of the pyruvic acid 2,4-dinitrophenylhydrazone derivative, and quantitative trapping in Amberlite XAD-7 columns, followed by radioactivity counting of the lipophilic eluate. No interferences from other 14C-labeled materials such as D-glucose, glycerol, L-lactate, L-serine, L-glutamate, L-phenylalanine, glycine, L-leucine, and L-arginine were observed. This inexpensive and high-speed method is applicable to the simultaneous determination of L-alanine-specific radioactivity for a large number of samples

  16. Enzymatic determination of carbon-14 labeled L-alanine in biological samples

    Energy Technology Data Exchange (ETDEWEB)

    Serra, F.; Palou, A.; Pons, A.

    1987-07-15

    A method for determination of L-alanine-specific radioactivity in biological samples is presented. This method is based on the specific enzymatic transformation of L-alanine to pyruvic acid hydrazone catalyzed by the enzyme L-alanine dehydrogenase, formation of the pyruvic acid 2,4-dinitrophenylhydrazone derivative, and quantitative trapping in Amberlite XAD-7 columns, followed by radioactivity counting of the lipophilic eluate. No interferences from other UC-labeled materials such as D-glucose, glycerol, L-lactate, L-serine, L-glutamate, L-phenylalanine, glycine, L-leucine, and L-arginine were observed. This inexpensive and high-speed method is applicable to the simultaneous determination of L-alanine-specific radioactivity for a large number of samples.

  17. Analytical Strategies for the Determination of Norepinephrine Reuptake Inhibitors in Pharmaceutical Formulations and Biological Fluids.

    Science.gov (United States)

    Saka, Cafer

    2016-01-01

    Norepinephrine reuptake inhibitors (NRIs) are a class of antidepressant drugs that act as reuptake inhibitors for the neurotransmitters norepinephrine and epinephrine. The present review provides an account of analytical methods published in recent years for the determination of NRI drugs. NRIs are atomoxetine, reboxetine, viloxazine and maprotiline. NRIs with less activity at other sites are mazindol, bupropion, tapentadol, and teniloxazine. This review focuses on the analytical methods including chromatographic, spectrophotometric, electroanalytical, and electrophoresis techniques for NRI analysis from pharmaceutical formulations and biological samples. Among all of the published methods, liquid chromatography with UV-vis or MS-MS detection is the most popular technique. The most the common sample preparation techniques in the analytical methods for NRIs include liquid-liquid extraction and solid-phase extraction. Besides the analytical methods for single components, some of the simultaneous determinations are also included in this review.

  18. Selective spectrofluorimetric determination of zinc in biological samples by Flow Injection Analysis (FIA)

    Energy Technology Data Exchange (ETDEWEB)

    Fernandez, P.; Perez Conde, C.; Gutierrez, A.; Camara, C. (Universidad Complutense, Madrid (Spain). Dept. de Quimica Analitica)

    1992-03-01

    The automatization of a spectrofluorimetric method for the determination of zinc at trace level is described. It is based on the formation of the fluorescent complex Zn(II)-5,7-dibromo-8-quinolinol (Zn(II)-DBQ) followed by extraction into diethylether using flow injection analysis. The optimum fluorescent emission is reached in hexamethylenetetramine (H{sub 2}MTA{sup +}/HMTA) buffer pH 6.0. A membrane phase separator was used. The calibration graph is linear up to 1.5 {mu}g/ml of Zn(II). The proposed method (detection limit 3 ng/ml) is very selective and has been successfully applied to determine Zn(II) in biological samples, tap waters and various food items. (orig.).

  19. Activation analytical determination of essential and toxic trace elements in biological material

    International Nuclear Information System (INIS)

    In order to determine the essential trace elements Hg, Ag, Cu and Se in food (potatoes, milk powder) and biological standard materials (fruit tree leaves), simple, fast radiochemical separation methods are worked out. Following oxidative decomposition and destillation of Hg, the elements silver, copper and selenium are found in the destillation residue and can be electrochemically enriched on an amalgamated Cu foil (determination of Ag and Se in the concentration range of 10-9 to 10-8g, of Cu in the range of 10-12 to 10-10 g), whilst the matrix elements Na, K, P are adsorbed on a column with 3 different inorganic ion exchangers. The eluate of the ion exchanger can be added directly to the multielement gamma spectroscopy. The possiblity of working purely instrumentally is demonstrated by 2 examples: multielement analysis of human hair and river water. (RB)

  20. The Possible Role of Dentin as a Piezoelectric Signal Generator by Determining the Elec-tromechanical Coupling Factor of Dentin

    Directory of Open Access Journals (Sweden)

    Atabak Shahidi

    2011-08-01

    Full Text Available Introduction: This article aimed at calculation of the electromechanical coupling factor of dentin which is an indicator of the effectiveness with which a piezoelectric material converts electrical en-ergy into mechanical energy, or vice versa. The hypothesis: The electro-mechanical coupling factor of dentin was determined in mode 11 and 33 by calculating the ratio of the produced electrical energy to the stored elastic energy in dentin under applied pressure. This study showed that the electromechanical coupling factor of dentin was affected by the direction of the applied force and the moisture content of dentin. Also dentin was a weak electromechanical energy converter which might be categorized as a piezoelectric pressure sensor.Evaluation of the hypothesis: Determination of the electrome-chanical coupling factor of dentin and its other piezoelectric constants is essential to investigate the biologic role of piezoelectricity in tooth.

  1. Determination of gadolinium-based MRI contrast agents in biological and environmental samples: A review

    Energy Technology Data Exchange (ETDEWEB)

    Telgmann, Lena [University of Münster, Institute of Inorganic and Analytical Chemistry, Münster (Germany); Sperling, Michael [University of Münster, Institute of Inorganic and Analytical Chemistry, Münster (Germany); European Virtual Institute for Speciation Analysis (EVISA), Münster (Germany); Karst, Uwe, E-mail: uk@uni-muenster.de [University of Münster, Institute of Inorganic and Analytical Chemistry, Münster (Germany)

    2013-02-18

    Highlights: ► All major methods for the analysis of Gd-based MRI contrast agents are discussed. ► Biological and environmental samples are covered. ► Pharmacokinetics and species transformation can be investigated. ► The figures of merit as limit of detection and analysis time are described. -- Abstract: The development of analytical methods and strategies to determine gadolinium and its complexes in biological and environmental matrices is evaluated in this review. Gadolinium (Gd) chelates are employed as contrast agents for magnetic resonance imaging (MRI) since the 1980s. In general they were considered as safe and well-tolerated, when in 2006, the disease nephrogenic systemic fibrosis (NSF) was connected to the administration of MRI contrast agents based on Gd. Pathogenesis and etiology of NSF are yet unclear and called for the development of several analytical methods to obtain elucidation in this field. Determination of Gd complex stability in vitro and in vivo, as well as the quantification of Gd in body fluids like blood and urine was carried out. Separation of the Gd chelates was achieved with high performance liquid chromatography (HPLC) and capillary electrophoresis (CE). For detection, various methods were employed, including UV–vis absorbance and fluorescence spectroscopy, electrospray ionization mass spectrometry (ESI-MS) and inductively coupled plasma mass spectrometry (ICP-MS). A second challenge for analysts was the discovery of high concentrations of anthropogenic Gd in surface waters draining populated areas. The source could soon be determined to be the increasing administration of Gd complexes during MRI examinations. Identification and quantification of the contrast agents was carried out in various surface and groundwater samples to determine the behavior and fate of the Gd chelates in the environment. The improvement of limits of detection (LOD) and limits of quantification (LOQ) was and still is the goal of past and ongoing

  2. Potentiometric detection in UPLC as an easy alternative to determine cocaine in biological samples.

    Science.gov (United States)

    Daems, Devin; van Nuijs, Alexander L N; Covaci, Adrian; Hamidi-Asl, Ezat; Van Camp, Guy; Nagels, Luc J

    2015-07-01

    The analytical methods which are often used for the determination of cocaine in complex biological matrices are a prescreening immunoassay and confirmation by chromatography combined with mass spectrometry. We suggest an ultra-high-pressure liquid chromatography combined with a potentiometric detector, as a fast and practical method to detect and quantify cocaine in biological samples. An adsorption/desorption model was used to investigate the usefulness of the potentiometric detector to determine cocaine in complex matrices. Detection limits of 6.3 ng mL(-1) were obtained in plasma and urine, which is below the maximum residue limit (MRL) of 25 ng mL(-1). A set of seven plasma samples and 10 urine samples were classified identically by both methods as exceeding the MRL or being inferior to it. The results obtained with the UPLC/potentiometric detection method were compared with the results obtained with the UPLC/MS method for samples spiked with varying cocaine concentrations. The intraclass correlation coefficient was 0.997 for serum (n =7) and 0.977 for urine (n =8). As liquid chromatography is an established technique, and as potentiometry is very simple and cost-effective in terms of equipment, we believe that this method is potentially easy, inexpensive, fast and reliable.

  3. Ambient and biological monitoring of cokeoven workers: determinants of the internal dose of polycyclic aromatic hydrocarbons.

    Science.gov (United States)

    Jongeneelen, F J; van Leeuwen, F E; Oosterink, S; Anzion, R B; van der Loop, F; Bos, R P; van Veen, H G

    1990-07-01

    Polycyclic aromatic hydrocarbons (PAH) were measured in the breathing zone air of 56 battery workers at two cokeovens during three consecutive days. The concentration of total PAH ranged up to 186 micrograms/m3. Preshift and end of shift urine samples were collected to determine 1-hydroxypyrene, a metabolite of pyrene. Control urine samples were available from 44 workers in the shipping yard of a hot rolling mill. The median values of 1-hydroxypyrene in urine of smoking and non-smoking controls were 0.51 and 0.17 mumol/mol creatinine, respectively. Concentrations of 1-hydroxypyrene up to 11.2 mumol/mol were found in the urine of the cokeoven workers. At the start of the three day working period after 32 hours off work, the 1-hydroxypyrene concentrations were four times higher and at the end of the working period 10 times higher compared with control concentrations. Excretion of 1-hydroxypyrene occurred with a half life of 6-35 hours. Both the ambient air monitoring data and the biological monitoring data showed that the topside workers were the heaviest exposed workers. The relation between air monitoring data and biological monitoring data was not strong. Multiple regression analysis was performed to identify determinants of the internal dose. The combination of exposure and smoking amplify each other and the use of a protective airstream helmet decreases the internal dose. An effect of alcohol consumption and the use of medication on the toxicokinetics of pyrene was not found.

  4. Influence of physical and chemical factors on biological leaching process of copper from printed circuit boards

    Directory of Open Access Journals (Sweden)

    J. Willner

    2013-04-01

    Full Text Available The article presents the results of the research regarding the biological leaching of this metal from electronic wastes components in the form of printed circuit boards. The purpose of the study was to evaluate the influence of some physical and chemical factors (e.g. pH, oxidation-reduction potential on bioleaching process and efficiency of copper transfer from solid phase into solution. Bioleaching experiments were carried out with pure cultures of Acidithiobacillus ferrooxidans. The obtained results were discussed.

  5. In search of a reliable technique for the determination of the biological stability of the organic matter in the mechanical-biological treated waste.

    Science.gov (United States)

    Barrena, Raquel; d'Imporzano, Giuliana; Ponsá, Sergio; Gea, Teresa; Artola, Adriana; Vázquez, Felícitas; Sánchez, Antoni; Adani, Fabrizio

    2009-03-15

    The biological stability determines the extent to which readily biodegradable organic matter has decomposed. In this work, a massive estimation of indices suitable for the measurement of biological stability of the organic matter content in solid waste samples has been carried out. Samples from different stages in a mechanical-biological treatment (MBT) plant treating municipal solid wastes (MSW) were selected as examples of different stages of organic matter stability in waste biological treatment. Aerobic indices based on respiration techniques properly reflected the process of organic matter biodegradation. Static and dynamic respirometry showed similar values in terms of aerobic biological activity (expressed as oxygen uptake rate, OUR), whereas cumulative oxygen consumption was a reliable method to express the biological stability of organic matter in solid samples. Methods based on OUR and cumulative oxygen consumption were positively correlated. Anaerobic methods based on biogas production (BP) tests also reflected well the degree of biological stability, although significant differences were found in solid and liquid BP assays. A significant correlation was found between cumulative oxygen consumption and ultimate biogas production. The results obtained in this study can be a basis for the quantitative measurement of the efficiency in the stabilization of organic matter in waste treatment plants, including MBT plants, anaerobic digestion of MSW and composting plants. PMID:18606494

  6. Determinants of the exclusive breastfeeding abandonment: psychosocial factors

    Directory of Open Access Journals (Sweden)

    Mariana Campos Martins Machado

    2014-12-01

    Full Text Available OBJECTIVE To assess the determinants of exclusive breastfeeding abandonment. METHODS Longitudinal study based on a birth cohort in Viçosa, MG, Southeastern Brazil. In 2011/2012, 168 new mothers accessing the public health network were followed. Three interviews, at 30, 60, and 120 days postpartum, with the new mothers were conducted. Exclusive breastfeeding abandonment was analyzed in the first, second, and fourth months after childbirth. The Edinburgh Postnatal Depression Scale was applied to identify depressive symptoms in the first and second meetings, with a score of ≥ 12 considered as the cutoff point. Socioeconomic, demographic, and obstetric variables were investigated, along with emotional conditions and the new mothers’ social network during pregnancy and the postpartum period. RESULTS The prevalence of exclusive breastfeeding abandonment at 30, 60, and 120 days postpartum was 53.6% (n = 90, 47.6% (n = 80, and 69.6% (n = 117, respectively, and its incidence in the fourth month compared with the first was 48.7%. Depressive symptoms and traumatic delivery were associated with exclusive breastfeeding abandonment in the second month after childbirth. In the fourth month, the following variables were significant: lower maternal education levels, lack of homeownership, returning to work, not receiving guidance on breastfeeding in the postpartum period, mother’s negative reaction to the news of pregnancy, and not receiving assistance from their partners for infant care. CONCLUSIONS Psychosocial and sociodemographic factors were strong predictors of early exclusive breastfeeding abandonment. Therefore, it is necessary to identify and provide early treatment to nursing mothers with depressive symptoms, decreasing the associated morbidity and promoting greater duration of exclusive breastfeeding. Support from health professionals, as well as that received at home and at work, can assist in this process.

  7. The determination of Exserohilum turcicum virulence factors in Serbia

    Directory of Open Access Journals (Sweden)

    Lević Jelena

    2008-01-01

    Full Text Available The determination of Exserohilum turcicum virulence factors and resistance responses of three sets of maize inbred lines (four differential, eight isogenic and 22 commercial inbreeds to three isolates of this pathogen under greenhouse conditions were studied. The maize inbreeds were selected according to previous testing of resistance based on lesion types in 194 inbreeds under field conditions of plant inoculation with the E. turcicum race 0 (designated as the isolate MRI-Et. The standard procedure was applied to obtained isolates MRIZP-1747 and MRIZP-1416 from resistant and susceptible lesion types, respectively. These lesions were developed on the same leaf of a plant of the experimental hybrid no. 163/99 grown in a nursery at Zemun Polje during 1999. The third isolate (MRIZP-1435 was isolated from a leaf sample originating from the location of Srbobran in which the occurrence of northern corn leaf blight (NCLB, caused by Exserohilum turcicum, was intensive. Based upon virulence/avirulence of three isolates of E. turcicum on differential maize inbred lines, it was found out that the isolate MRIZP-1747 could be classified as race 0, whereas isolates MRIZP-1416 and MRIZP-1435 could be classified as race 1. These are the first results that confirm the presence of race 1 of E. turcicum in Serbia. Not including differential lines, 22 and six lines were resistant to race 0 and race 1, respectively, while eight and five lines were resistant and susceptible to both races, respectively. All isogenic lines not containing the Ht gene were susceptible to both races 0 and 1.

  8. Determination of lead in biological samples of children with different physiological consequences using cloud point extraction method.

    Science.gov (United States)

    Shah, Faheem; Kazi, Tasneem Gul; Ullah, Naeem; Afridi, Hassan Imran

    2013-06-01

    In present study, lead (Pb) level in biological samples of children with physiological disorders (liver, bone, and gastrointestinal; age ranged 1-10 years) have been assessed. For comparison purpose, age-matched healthy children were also selected. Cloud point extraction (CPE) was employed for preconcentration of Pb in acid-digested biological samples prior to its determination by flame atomic absorption spectrometry (FAAS). Dithizone (diphenylthiocarbazone) and nonionic surfactant Triton X-114 (TX-114) were used as complexing reagent and extractant, respectively. The effects of several experimental variables on proposed CPE were evaluated. Under the optimum experimental conditions, the observed detection limit (LOD) and the enhancement factor (EF) were 0.08 μg L(-1) and 53, respectively. Relative standard deviation (RSD) of 10 μg L(-1) Pb was 3.4 %. It was observed that children with liver-, bone-, and gastrointestinal-related disorders had three- to fourfold higher Pb level in blood and scalp hair samples. PMID:23625698

  9. Determination of lead in biological samples of children with different physiological consequences using cloud point extraction method.

    Science.gov (United States)

    Shah, Faheem; Kazi, Tasneem Gul; Ullah, Naeem; Afridi, Hassan Imran

    2013-06-01

    In present study, lead (Pb) level in biological samples of children with physiological disorders (liver, bone, and gastrointestinal; age ranged 1-10 years) have been assessed. For comparison purpose, age-matched healthy children were also selected. Cloud point extraction (CPE) was employed for preconcentration of Pb in acid-digested biological samples prior to its determination by flame atomic absorption spectrometry (FAAS). Dithizone (diphenylthiocarbazone) and nonionic surfactant Triton X-114 (TX-114) were used as complexing reagent and extractant, respectively. The effects of several experimental variables on proposed CPE were evaluated. Under the optimum experimental conditions, the observed detection limit (LOD) and the enhancement factor (EF) were 0.08 μg L(-1) and 53, respectively. Relative standard deviation (RSD) of 10 μg L(-1) Pb was 3.4 %. It was observed that children with liver-, bone-, and gastrointestinal-related disorders had three- to fourfold higher Pb level in blood and scalp hair samples.

  10. Biological Determinism and the Narrative of Adjustment: The High School Biology Textbooks of Truman Jesse Moon, c. 1921-1963

    Science.gov (United States)

    Selden, Steven

    2007-01-01

    While the mainline eugenics movement in early 20th century was closely associated with racism and the European Holocaust and was present in biology textbooks in the early 20th century, the following article finds that a transformed eugenics could be found the U.S. science curriculum by mid-century. The following article analyzes the content of 73…

  11. Psychosocial and Biological Factors Contributing to Body Weight Gain in Schizophrenia

    Directory of Open Access Journals (Sweden)

    Shae-Leigh C. Vella

    2011-11-01

    Full Text Available Overweight and obesity are frequently reported to be a significant issue in schizophrenia resulting in the inherent complications of these disorders. Body weight gain also commonly results from treatment with the most tolerable and efficacious pharmacological treatments, second-generation antipsychotics. However there are numerous other factors that contribute to increased body mass in individuals with schizophrenia prior to the initiation of treatment. With prior research indicating that individuals with schizophrenia have higher rates of overweight and obesity before treatment. Therefore this article provides a review of pertinent issues associated with body weight gain in schizophrenia in an attempt to delineate the impact of both the disease and treatment upon body weight gain. The results of the review indicate that body weight gain in schizophrenia occurs from both psychosocial and biological factors that are further compounded by antipsychotic treatment. The article concludes with recommendations for future research.

  12. Recent advances in the structural molecular biology of Ets transcription factors: interactions, interfaces and inhibition.

    Science.gov (United States)

    Cooper, Christopher D O; Newman, Joseph A; Gileadi, Opher

    2014-02-01

    The Ets family of eukaryotic transcription factors is based around the conserved Ets DNA-binding domain. Although their DNA-binding selectivity is biochemically and structurally well characterized, structures of homodimeric and ternary complexes point to Ets domains functioning as versatile protein-interaction modules. In the present paper, we review the progress made over the last decade to elucidate the structural mechanisms involved in modulation of DNA binding and protein partner selection during dimerization. We see that Ets domains, although conserved around a core architecture, have evolved to utilize a variety of interaction surfaces and binding mechanisms, reflecting Ets domains as dynamic interfaces for both DNA and protein interaction. Furthermore, we discuss recent advances in drug development for inhibition of Ets factors, and the roles structural biology can play in their future.

  13. On Examination Malpractice in Nigeria Universities: Factor Analysis Determination

    Directory of Open Access Journals (Sweden)

    A.A. Akinrefon

    2016-08-01

    Full Text Available Examination malpractice has become an epidemic in the nation educational system. This study seeks to assess the pattern of examination malpractice in higher institutions in Nigeria, their causes, effects and also proffer solutions. The sample size of the study was calculated using Yaro Yamane formula. The instrument used for the study was a questionnaire titled Causes and Effects of Examination Malpractice (CEEMQ. The data collected were analyzed using Factor analysis and Principal component analysis. The findings from the factor analysis in factor loading 1 revealed that items 13 (0.5998, 29 (0.6785 and item 8 (0.5062 are the major causes of examination malpractice. Factor loading 2 revealed that item 26 (0.6594 and item 25 (0.6342 are the major solutions and effects of exam malpractice. Analysis from factor loading 8 revealed that factor 15 (0.5154 is also a major cause of exam malpractice.

  14. A study to determine influential factors on product positioning

    Directory of Open Access Journals (Sweden)

    Naser Azad

    2013-08-01

    Full Text Available Product positioning plays an important role on business development especially in food industry. In this paper, we perform an exploration study to find important factors influencing product positioning in Iranian food industry. The study designs a questionnaire in Likert scale and distributes it among 260 randomly selected people from food industry. Cronbach alpha has been calculated as 0.86 in preliminary stage and final 0.697 in final stage, which are statistically acceptable. The study uses factor analysis to find important factors and detects six important factors including marketing organization, market analysis, past perception strategy, product presentation, brand loyalty and dynamic organizational structure.

  15. The use of self-determination theory to foster environmental motivation in an environmental biology course

    Science.gov (United States)

    Darner, Rebekka

    A scientifically literate person is one who understands the nature of science, its processes, products, and their appropriate application to decision-making contexts. The impetus to make informed decisions about environmental issues is environmental motivation. I examined students' environmental motivation, its relationship to scientific knowledge, and how environmental motivation can be fostered in a science classroom. This study took place in a college-level environmental biology course in which the instructor attempted to support students' basic psychological needs, as defined by self-determination theory (SDT). The first question was to what extent does an SDT-guided environmental biology course differ from a non-SDT-guided course in the degree to which it fostered self-determined motivation toward the environment. The administration of a well-validated scale to two sections before, after, and six months following the end of the course indicated that SDT-guided instruction is a plausible way to foster environmental motivation in the classroom. The second question was what are the multiple influences on fostering self-determined motivation toward the environment in an SDT-guided course. Path analysis indicated that environmental motivation can be partially accomplished in an environmental biology course by conveying to students that they are cared for, are connected to others, and can trust others while solving environmental problems. The third question sought to characterize students' scientific conceptualizations as they solve environmental problems and the extent to which their conceptualizations relate to the satisfaction of their need for competence. Students were videotaped during in-class problem-solving, after which stimulated-recall interviews were conducted. Grounded theory and an established coding scheme were combined to analyze these data, which resulted in three grounded hypotheses about what characterizes students' scientific knowledge when they

  16. Determinants of serum brain-derived neurotrophic factor

    NARCIS (Netherlands)

    Bus, B.A.A.; Molendijk, M.L.; Penninx, B.J.; Buitelaar, J.K.; Kenis, G.; Prickaerts, J.; Elzinga, B.M.; Oude Voshaar, R.C.

    2011-01-01

    BACKGROUND: Brain-derived neurotrophic factor (BDNF) belongs to the neurotrophin family of growth factors and affects the survival and plasticity of neurons in the adult central nervous system. The high correlation between cortical and serum BDNF levels has led to many human studies on BDNF levels i

  17. Determinants of serum brain-derived neurotrophic factor

    NARCIS (Netherlands)

    Bus, B. A. A.; Molendijk, M. L.; Penninx, B. J. W. H.; Buitelaar, J. K.; Kenis, G.; Prickaerts, J.; Elzinga, B. M.; Voshaar, R. C. Oude

    2011-01-01

    Background: Brain-derived neurotrophic factor (BDNF) belongs to the neurotrophin family of growth factors and affects the survival and plasticity of neurons in the adult central nervous system. The high correlation between cortical and serum BDNF levels has led to many human studies on BDNF levels i

  18. Determining factors for high performance silicone rubber microwave absorbing materials

    International Nuclear Information System (INIS)

    Silicone rubber microwave absorbing materials (RMAMs) based on ferrite as the major absorbent were prepared by the mechanical blending method. The determining factors for the complex permittivity, complex permeability, and reflectivity of RMAM were thoroughly investigated with various samples including different crystal structures of Ba-ferrite (M-type, W-type, and Y-type), the ferrite with doped elements (Ba, Sr), the materials' thickness, the combination ratio of ferrite and carbonyl iron. The effects of surface modification and loading amount of ferrite on the mechanical properties, processing performance, and absorbing property of RMAM were also assessed. The results show that W-type Ba-ferrite based RMAM exhibits better absorbing property at high frequencies (8-18 GHz) than the other two barium ferrites (M-type and Y-type) based ones, and the absorbing property of RMAM based on Sr-ferrite is best. As the thickness of RMAM and the amount of absorbents increase, the absorption peak moves toward low frequency, the absorption frequency bandwidth is narrowed, and the reflectivity first decreases and later increases. The optimum thickness is 1.5-1.7 mm, and the amount of ferrite is 450 parts per hundreds of rubber (phr). Surface modification of the absorbent with silane coupling agent could improve the mechanical properties and processing performance of RMAM. It is concluded that there will be a synergistic effect when carbonyl iron (CI) is used in combination with Sr-ferrite (Sr-W) in an appropriate proportion. When the total volume fraction of absorbents is 51%, the optimum ratio of Cl to Sr-W is 17:34, the absorption frequency bandwidth (<-10 dB) is about 8 GHz, and the absorption area is -99 dB. - Highlights: → W-type ferrite exhibits better absorbing property than M-type and Y-type at 8-18 GHz. → Sr-W based RMAM has best absorbing property of Ba- and Sr-ferrite. → The optimum thickness of RMAM is 1.5-1.7 mm, and the amount of ferrite is 450 phr.

  19. The Newcastle 85+ study: biological, clinical and psychosocial factors associated with healthy ageing: study protocol

    Directory of Open Access Journals (Sweden)

    Martin-Ruiz Carmen

    2007-06-01

    Full Text Available Abstract Background The UK, like other developed countries, is experiencing a marked change in the age structure of its population characterised by increasing life expectancy and continuing growth in the older fraction of the population. There is remarkably little up-to-date information about the health of the oldest old (over 85 years, demographically the fastest growing section of the population. There is a need, from both a policy and scientific perspective, to describe in detail the health status of this population and the factors that influence individual health trajectories. For a very large proportion of medical conditions, age is the single largest risk factor. Gaining new knowledge about why aged cells and tissues are more vulnerable to pathology is likely to catalyse radical new insights and opportunities to intervene. The aims of the Newcastle 85+ Study are to expose the spectrum of health within an inception cohort of 800 85 year-olds; to examine health trajectories and outcomes as the cohort ages and their associations with underlying biological, medical and social factors; and to advance understanding of the biological nature of ageing. Methods A cohort of 800 85 year olds from Newcastle and North Tyneside will be recruited at baseline and followed until the last participant has died. Eligible individuals will be all those who turn 85 during the year 2006 (i.e. born in 1921 and who are registered with a Newcastle or North Tyneside general practice. Participants will be visited in their current residence (own home or institution by a research nurse at baseline, 18 months and 36 months. The assessment protocol entails a detailed multi-dimensional health assessment together with review of general practice medical records. Participants will be flagged with the NHS Central Register to provide details of the date and cause of death. Discussion The Newcastle 85+ Study will address key questions about health and health-maintenance in the

  20. Determination of zinc stable isotopes in biological materials using isotope dilution inductively coupled plasma mass spectrometry

    International Nuclear Information System (INIS)

    A method is described for using isotope dilution to determine both the amount of natural zinc and enriched isotopes of zinc in biological samples. Isotope dilution inductively coupled plasma mass spectrometry offers a way to quantify not only the natural zinc found in a sample but also the enriched isotope tracers of zinc. Accurate values for the enriched isotopes and natural zinc are obtained by adjusting the mass count rate data for measurable instrumental biases. Analytical interferences from the matrix are avoided by extracting the zinc from the sample matrix using diethylammonium diethyldithiocarbamate. The extraction technique separates the zinc from elements which form interfering molecular ions at the same nominal masses as the zinc isotopes. Accuracy of the method is verified using standard reference materials. The detection limit is 0.06 μg Zn per sample. Precision of the abundance ratios range from 0.3-0.8%. R.S.D. for natural zinc concentrations is about 200-600 μg g-1. The accuracy and precision of the measurements make it possible to follow enriched isotopic tracers of zinc in biological samples in metabolic tracer studies. (author). 19 refs.; 1 fig., 4 tabs

  1. The challenge of determining the need for remediation following a wide-area biological release.

    Science.gov (United States)

    Raber, Ellen

    2011-09-01

    Recovering from a biological attack is a complex process requiring the successful resolution of numerous challenges. The Interagency Biological Restoration Demonstration program is one of the first multiagency efforts to develop strategies and tools that could be effective following a wide-area release of B. anthracis spores. Nevertheless, several key policy issues and associated science and technology issues still need to be addressed. For example, more refined risk assessment and management approaches are needed to help evaluate "true" public health risk. Once the risk is understood, that information can be considered along with the types of characterization activities deemed necessary to determine whether the cost and time of decontamination are actually warranted. This commentary offers 5 recommendations associated with decision making regarding decontamination and clearance options that should accompany a comprehensive risk analysis leading to more effective risk management decisions. It summarizes some of the most important technological gaps that still need to be addressed to help decision makers in their objective of reducing health risks to an acceptable level. The risk management approach described should enable decision makers to improve credibility and gain public acceptance, especially when an adequate science and technology base is available to support the required decisions. PMID:21882967

  2. ALOUD: Adult Learning Open University Determinants Study: Association between biological and psychological determinants and study success in adult formal distance education

    NARCIS (Netherlands)

    De Groot, Renate; Neroni, Joyce; Gijselaers, Jérôme; Kirschner, Paul A.

    2012-01-01

    De Groot, R. H. M., Neroni, J., Gijselaers, J., & Kirschner, P. A. (2012, 6 December). ALOUD: Adult Learning Open University Determinants Study: Associations between biological and psychological determinants and study success in adult formal distance education. Presented at the Open University for t

  3. The ALOUD Study: Adult Learning Open University Determinants Study - Influence of biological and psychological determinants on study success in formal lifelong learning in adults

    NARCIS (Netherlands)

    Gijselaers, Jérôme; Neroni, Joyce; De Groot, Renate; Kirschner, Paul A.

    2011-01-01

    Gijselaers, H. J. M., Neroni, J., De Groot, R. H. M., & Kirschner, P. A. (2011, September). The ALOUD Study: Adult Learning Open University Determinants Study - Influence of biological and psychological determinants on study success in formal lifelong learning in adults. Presentation given for visit

  4. Methylmercury determination in biological samples using electrothermal atomic absorption spectrometry after acid leaching extraction

    Energy Technology Data Exchange (ETDEWEB)

    Saber-Tehrani, Mohammad; Hashemi-Moghaddam, Hamid; Givianrad, Mohammad Hadi; Abroomand-Azar, Parviz [Islamic Azad University, Department of Chemistry, Science and Research Branch, Tehran (Iran)

    2006-11-15

    An efficient and sensitive method for the determination of methylmercury in biological samples was developed based on acid leaching extraction of methylmercury into toluene. Methylmercury in the organic phase was determined by electrothermal atomic absorption spectrometry (ETAAS). The methylmercury signal was enhanced and the reproducibility increased by formation of certain complexes and addition of Pd-DDC modifier. The complex of methylmercury with DDC produced the optimum analytical signal in terms of sensitivity and reproducibility compared to complexes with dithizone, cysteine, 1,10-phenanthroline, and diethyldithiocarbamate. Method performance was optimized by modifying parameters such as temperature of mineralization, atomization, and gas flow rate. The limit of detection for methylmercury determination was 0.015 {mu}g g{sup -1} and the RSD of the whole procedure was 12% for human teeth samples (n=5) and 15.8% for hair samples (n=5). The method's accuracy was investigated by using NIES-13 and by spiking the samples with different amounts of methylmercury. The results were in good agreement with the certified values and the recoveries were 88-95%. (orig.)

  5. Preconcentration and determination of heavy metals in water, sediment and biological samples

    Directory of Open Access Journals (Sweden)

    Shirkhanloo Hamid

    2011-01-01

    Full Text Available In this study, a simple, sensitive and accurate column preconcentration method was developed for the determination of Cd, Cu and Pb ions in river water, urine and sediment samples by flame atomic absorption spectrometry. The procedure is based on the retention of the analytes on a mixed cellulose ester membrane (MCEM column from buffered sample solutions and then their elution from the column with nitric acid. Several parameters, such as pH of the sample solution, volume of the sample and eluent and flow rates of the sample were evaluated. The effects of diverse ions on the preconcentration were also investigated. The recoveries were >95 %. The developed method was applied to the determination of trace metal ions in river water, urine and sediment samples, with satisfactory results. The 3δ detection limits for Cu, Pb and Cd were found to be 2, 3 and 0.2 μg dm−3, respectively. The presented procedure was successfully applied for determination of the copper, lead and cadmium contents in real samples, i.e., river water and biological samples.

  6. A simple kinetic spectrophotometric method for the determination of oxamniquine in formulations and spiked biological fluids.

    Science.gov (United States)

    Rizk, M; Belal, F; Ibrahim, F; Ahmed, S M; El-Enany, N M

    2000-08-15

    A simple and sensitive kinetic method for the determination of oxamniquine in pharmaceutical preparations and biological fluids was developed. The procedure is based upon a kinetic investigation of the oxidation reaction of the drug with alkaline potassium permanganate at room temperature for a fixed time of 20 min. The absorbance of the colored manganate ions was measured at 610 nm. Alternatively, the decrease in the absorbance of potassium permanganate after addition of the drug was measured at 525 nm. The absorbance concentration plots in both procedures were rectilinear over the range 0.5-4 microg ml(-1). The concentration of oxamniquine is calculated using the corresponding calibration equation for the fixed-time method. The determination of oxamniquine by fixed-concentration and rate-constant methods was feasible with the calibration equations obtained but the fixed time method had been found to be more applicable. Both procedures were applied to the determination of oxamniquine in formulations. The results obtained were in good agreement with those obtained using the official method. The fixed time method of 20 min was further applied to spiked human urine and plasma, the recoveries (%) were 100.94 +/- 0.57 and 98.07 +/- 0.88 for urine and plasma, respectively, at 610 nm, and 97.51 +/- 1.27 and 95.69 +/- 1.23 for urine and plasma, respectively, at 525 nm. PMID:10933544

  7. Analytical applications of oscillatory chemical reactions: determination of some pharmaceuticaly and biologically important compounds

    Directory of Open Access Journals (Sweden)

    Pejić Nataša D.

    2012-01-01

    Full Text Available Novel analytical methods for quantitive determination of analytes based on perturbations of oscillatory chemical reactions realized under open reactor conditions (continuosly fed well stirred tank reactor, CSTR, have been developed in the past twenty years. The proposed kinetic methods are generally based on the ability of the analyzed substances to change the kinetics of the chemical reactions matrix. The unambiguous correlation of quantitative characteristics of perturbations, and the amount (concentration of analyte expressed as a regression equation, or its graphics (calibration curve, enable the determination of the unknown analyte concentration. Attention is given to the development of these methods because of their simple experimental procedures, broad range of linear regression ( 10-7 10-4 mol L-1 and low limits of detection of analytes ( 10-6 10-8 mol L1, in some cases even lower than 10-12 mol L-1. Therefore, their application is very convenient for routine analysis of various inorganic and organic compounds as well as gases. This review summarizes progress made in the past 5 years on quantitative determination of pharmaceutically and biologically important compounds.

  8. Cloud point extraction for the determination of cadmium and lead in biological samples by graphite furnace atomic absorption spectrometry

    Science.gov (United States)

    Maranhão, Tatiane De A.; Borges, Daniel L. G.; da Veiga, Márcia A. M. S.; Curtius, Adilson J.

    2005-06-01

    The phase-separation phenomenon of non-ionic surfactants occurring in aqueous solution was used for the extraction of Cd and Pb from digested biological samples. After complexation with O,O-diethyldithiophosphate (DDTP) in hydrochloric acid medium, the analytes are quantitatively extracted to the phase rich in the non-ionic surfactant octylphenoxypolyethoxyethanol (Triton X-114) after centrifugation. Methanol acidified with 0.1 mol L-1 HNO3 was added to the surfactant-rich phase prior to its analysis by electrothermal atomic absorption spectrometry (ET AAS). The adopted concentrations for DDTP, Triton X-114 and hydrochloric acid were all optimized. Pyrolysis and atomization temperatures were optimized using the extracts and pyrolysis temperatures of 700 °C for both elements and atomization temperatures of 1400 and 1600 °C for cadmium and lead, respectively, were used without adding any modifier, which shows that considerable analyte stabilization is provided by the medium itself. A more detailed investigation was carried out to determine which components of the extract were responsible for the high thermal stability achieved and it revealed that the amount of DDTP added and the phosphorus content of the digested samples contributed significantly to this phenomenon. Detection limits (3σB) of 6 and 40 ng g-1, along with enrichment factors of 129 and 18 for Cd and Pb, respectively, were achieved. The proposed procedure was applied to the analysis of five certified biological reference materials after microwave-assisted acid digestion in a mixture of H2O2 and HNO3. Comparison with certified values was performed for accuracy evaluation, resulting in good agreement according to the t-test for a 95% confidence level. The high efficiency of cloud point extraction to carry out the determination of the studied analytes in complex matrices was, therefore, demonstrated.

  9. Cloud point extraction for the determination of cadmium and lead in biological samples by graphite furnace atomic absorption spectrometry

    Energy Technology Data Exchange (ETDEWEB)

    Maranhao, Tatiane de A. [Departamento de Quimica, Universidade Federal de Santa Catarina, 88040-900, Florianopolis, SC (Brazil); Borges, Daniel L.G. [Departamento de Quimica, Universidade Federal de Santa Catarina, 88040-900, Florianopolis, SC (Brazil)]. E-mail: daniel@qmc.ufsc.br; Veiga, Marcia A.M.S. da [Instituto de Quimica, Universidade de Sao Paulo, 05513-970, CP 26077, Sao Paulo, SP (Brazil); Curtius, Adilson J. [Departamento de Quimica, Universidade Federal de Santa Catarina, 88040-900, Florianopolis, SC (Brazil)

    2005-06-30

    The phase-separation phenomenon of non-ionic surfactants occurring in aqueous solution was used for the extraction of Cd and Pb from digested biological samples. After complexation with O,O-diethyldithiophosphate (DDTP) in hydrochloric acid medium, the analytes are quantitatively extracted to the phase rich in the non-ionic surfactant octylphenoxypolyethoxyethanol (Triton X-114) after centrifugation. Methanol acidified with 0.1 mol L{sup -1} HNO{sub 3} was added to the surfactant-rich phase prior to its analysis by electrothermal atomic absorption spectrometry (ET AAS). The adopted concentrations for DDTP, Triton X-114 and hydrochloric acid were all optimized. Pyrolysis and atomization temperatures were optimized using the extracts and pyrolysis temperatures of 700 deg. C for both elements and atomization temperatures of 1400 and 1600 deg. C for cadmium and lead, respectively, were used without adding any modifier, which shows that considerable analyte stabilization is provided by the medium itself. A more detailed investigation was carried out to determine which components of the extract were responsible for the high thermal stability achieved and it revealed that the amount of DDTP added and the phosphorus content of the digested samples contributed significantly to this phenomenon. Detection limits (3{sigma} {sub B}) of 6 and 40 ng g{sup -1}, along with enrichment factors of 129 and 18 for Cd and Pb, respectively, were achieved. The proposed procedure was applied to the analysis of five certified biological reference materials after microwave-assisted acid digestion in a mixture of H{sub 2}O{sub 2} and HNO{sub 3}. Comparison with certified values was performed for accuracy evaluation, resulting in good agreement according to the t-test for a 95% confidence level. The high efficiency of cloud point extraction to carry out the determination of the studied analytes in complex matrices was, therefore, demonstrated.

  10. HIV Infection among Young People in Northwest Tanzania: The Role of Biological, Behavioural and Socio-Demographic Risk Factors.

    Directory of Open Access Journals (Sweden)

    Francesca Lemme

    Full Text Available Young people are at high risk of HIV and developing appropriate prevention programmes requires an understanding of the risk factors for HIV in this age group. We investigated factors associated with HIV among participants aged 15-30 years in a 2007-8 cross-sectional survey nested within a community-randomised trial of the MEMA kwa Vijana intervention in 20 rural communities in northwest Tanzania.We analysed data for 7259(53% males and 6476(47% females. Using a proximate-determinant conceptual framework and conditional logistic regression, we obtained sex-specific Odds Ratios (ORs for the association of HIV infection with socio-demographic, knowledge, behavioural and biological factors.HSV-2 infection was strongly associated with HIV infection (females: adjOR 4.4, 95%CI 3.2-6.1; males: adjOR 4.2, 95%CI 2.8-6.2. Several socio-demographic factors (such as age, marital status and mobility, behavioural factors (condom use, number and type of sexual partnerships and biological factors (blood transfusion, lifetime pregnancies, genital ulcers, Neisseria gonorrhoeae were also associated with HIV infection. Among females, lifetime sexual partners (linear trend, p<0.001, ≥2 partners in the past year (adjOR 2.0, 95%CI 1.4-2.8, ≥2 new partners in the past year (adjOR 1.9 95%CI 1.2, 3.3 and concurrent partners in the past year (adjOR 1.6 95%CI 1.1, 2.4 were all associated with HIV infection.Efforts must be intensified to find effective interventions to reduce HSV-2. Effective behavioural interventions focusing on reducing the number of sexual partnerships and risk behaviour within partnerships are also needed. An increase in risky sexual behaviour may occur following marriage dissolution or when a young woman travels outside of her community and interventions addressing the needs of these subgroups of vulnerable women may be important.ClinicalTrial.gov NCT00248469.

  11. Stone Columns - Determination of the soil improvement factor

    Science.gov (United States)

    Pivarč, J.

    2011-09-01

    A stone column is one of the soil stabilizing methods that is used to increase strength, decrease the compressibility of soft and loose fine graded soils, accelerate a consolidation effect and reduce the liquefaction potential of soils. The columns consist of compacted gravel or crushed stone arranged by a vibrator. This paper deals with Priebe's theory (1976) on the design of an improvement factor, which belongs among the most used analytical methods and also describes the numerical and laboratory models of stone columns. The improvement factors calculated from numerical and laboratory models are compared with the improvement factors resulting from Priebe's theory.

  12. X-ray microanalysis - determination of some correction factors. The penetration factor

    International Nuclear Information System (INIS)

    Correction factors owing to electron penetration had been determined according to the following scheme. Let CA' be the measured concentration of element A in an alloy AB. Then, the absorption correction can be carried out following Philibert's method. Neglecting fluorescence absorption, we can write: CA' = 1/(1+CB*SB*(1-RA*Z*A)/CA*SA*(1-RB*Z*B)) where CA is the true mass concentration of element A in AB, S the stopping power which determines the penetration of an electron, R the back-scatter coefficient, Z the fraction of back scattered electrons lost for ionisation. Integer values of Z (1 or 0) enable the penetration yield to be calculated, choosing methods are proposed, our results are the following ones: S(Al)/S(Ni) = 1.35 for 10 kV and 1.40 for 35 kV; S(Al)/S(Fe) = 1.21 for 10 kV and 1.35 for 35 kV; S(Fe)/S(U) = 1.71 for 20 kV, 1.72 for 25 kV, 1.70 for 30 kV and 1.68 for 35 kV; S(Al)/S(U) = 2.48 for 15 kV, 2.39 for 20 kV, 2.33 for 25 kV, 2.23 for 30 kV and 2.20 for 35 kV. These values are compared to Nelms' (obtained assuming Bethe's law) and to those which can determine from Kulenkampff's experiments about energy spectrum of back-scattered electrons. (authors)

  13. Determination of specificity influencing residues for key transcription factor families

    DEFF Research Database (Denmark)

    Patel, Ronak Y.; Garde, Christian; Stormo, Gary D.

    2015-01-01

    Transcription factors (TFs) are major modulators of transcription and subsequent cellular processes. The binding of TFs to specific regulatory elements is governed by their specificity. Considering the gap between known TFs sequence and specificity, specificity prediction frameworks are highly...

  14. Lifestyle and dietary factors determine age at natural menopause

    OpenAIRE

    Sapre, Shilpa; Thakur, Ratna

    2014-01-01

    A literature search was done using PubMed. The age at natural menopause (ANM) depends on various factors like genetic, environmental, socioeconomic, reproductive, dietary, and lifestyle of which some like nulliparity, vegetarian diet, smoking, high fat intake, cholesterol, and caffeine accelerates; while others like parity, prior use of oral contraceptive pills, and Japanese ethnicity delays the ANM. ANM is an important risk factor for long-term morbidity and mortality; and hence, the need to...

  15. What Factors Determine the Uptake of A-level Physics?

    OpenAIRE

    Gill, Timothy; Bell, John F

    2011-01-01

    Abstract There has been much concern recently in the UK about the decline in the number of students studying physics beyond age 16. To investigate why this might be we used data from a national database of student qualifications and a multilevel modelling technique to investigate which factors had the greatest impact on the uptake of physics at Advanced Level (A-level) in a particular year. Each factor of interest was entered into a separate model, whilst accounting for prior attai...

  16. NEW DETERMINANT FACTORS OF CHANGE MANAGEMENT IN THE HOSPITALITY INDUSTRY

    OpenAIRE

    Eugenia ALECU

    2013-01-01

    The factors that we took into account the following important elements: for goods and capital (brand promotion, reliable predictions against risk factors, knowledge capital, intangible values for hotels), for health and safety (the easily with which diseases can cross oceans and borders and multiplying rows of old and new infections, some impossible to treat, strict control of food and non-food products entering in the hotel), for new management (planning education and training process in hos...

  17. Factors in seventh grade academics associated with performance levels on the tenth grade biology end of course test in selected middle and high schools in northwest Georgia

    Science.gov (United States)

    Ward, Jennifer Henry

    This study attempted to identify factors in seventh grade academics that are associated with overall success in tenth grade biology. The study addressed the following research questions: Are there significant differences in performance levels in seventh grade Criterion Referenced Competency Test (CRCT) scores in science, math, reading, and language arts associated with performance categories in tenth grade biology End of Course Test (EOCT) and the following demographic variables : gender, ethnicity, socioeconomic status, disability category, and English language proficiency level? Is there a relationship among the categorical variables on the tenth grade biology EOCT and the same five demographic variables? Retrospective causal comparative research was used on a representative sample from the middle schools in three North Georgia counties who took the four CRCTs in the 2006-2007 school year, and took the biology EOCT in the 2009-2010 school year. Chi square was used to determine the relationships of the various demographic variables on three biology EOCT performance categories. Twoway ANOVA determined relationships between the seventh grade CRCT scores of students in the various demographic groups and their performance levels on the biology EOCT. Students' performance levels on the biology EOCT matched their performance levels on the seventh grade CRCTs consistently. Females performed better than males on all seventh grade CRCTs. Black and Hispanic students did worse than White and Asian/Asian Indian students on the math CRCT. Students living in poverty did worse on reading and language arts CRCTs than students who were better off. Special education students did worse on science, reading, and language arts CRCTs than students not receiving special education services. English language learners did worse than native English speakers on all seventh grade CRCTs. These findings suggest that remedial measures may be taken in the seventh grade that could impact

  18. Cystatin C and lactoferrin concentrations in biological fluids as possible prognostic factors in eye tumor development

    Directory of Open Access Journals (Sweden)

    Mariya A. Dikovskaya

    2013-08-01

    Full Text Available Objectives. To investigate the possible role of cystatin C in eye biological fluids locally and in serum and lactoferrin revealing anti-tumor activity in eye tumor development. Background. The increased number of eye tumors was registered recently not only in the countries with high insolation, but also in the northern countries including Russia (11 cases per million of population. Search for new biological markers is important for diagnosis and prognosis in eye tumors. Cystatin C, an endogenous inhibitor of cysteine proteases, plays an important protective role in several tumors. Lactoferrin was shown to express anti-tumor and antiviral activities. It was hypothesized that cystatin C and lactoferrin could serve as possible biomarkers in the diagnosis of malignant and benign eye tumors. Study design. A total of 54 patients with choroidal melanoma and benign eye tumors were examined (part of them undergoing surgical treatment. Serum, tear fluid and intraocular fluid samples obtained from the anterior chamber of eyes in patients with choroidal melanoma were studied. Methods. Cystatin C concentration in serum and eye biological fluids was measured by commercial ELISA kits for human (BioVendor, Czechia; lactoferrin concentration – by Lactoferrin-strip D 4106 ELISA test systems (Vector-BEST, Novosibirsk Region, Russia. Results. Cystatin C concentration in serum of healthy persons was significantly higher as compared to tear and intraocular fluids. In patients with choroidal melanoma, increased cystatin C concentration was similar in tear fluid of both the eyes. Lactoferrin level in tear fluid of healthy persons was significantly higher than its serum level. Significantly increased lactoferrin concentration in tear fluid was noted in patients with benign and malignant eye tumors. Conclusion. Increased level of cystatin C in tear fluid seems to be a possible diagnostic factor in the eye tumors studied. However, it does not allow us to differentiate

  19. Silica-titania xerogel for solid phase spectrophotometric determination of salicylate and its derivatives in biological liquids and pharmaceuticals

    OpenAIRE

    Morosanova, Maria A.; Morosanova, Elena I.

    2015-01-01

    Background Salicylic acid and its derivatives are widely used drugs with potential toxicity. The main areas of salicylate derivatives determination are biological liquids and pharmaceuticals analysis. Results Silica-titania xerogel has been used for solid phase spectrophotometric determination of various salicylate derivatives (salicylate, salicylamide, methylsalicylate). The reaction conditions influence on the interaction of salicylate derivatives with silica-titania xerogels has been inves...

  20. Expression of Human Vascular Endothelial Growth Factor (VEGF165) in Pichia pastoris and Its Biological Activity

    Institute of Scientific and Technical Information of China (English)

    2001-01-01

    Objective To express human vascular endothelial growth factor (hVEGF165) cDNA in Pichia pastroris, purify the expressed product and detect the biological activity of it. Methods  By inserting hVEGF165 cDNA coding 165 amino acid residues into Pichia pastoris expression vector pPIC9K containing AOX1 promoter and the sequences of α secreting signal peptides, a recombinant expression plasmid pPIC9K/hVEGF165 was constructed and transformed to yeast host strain KM71, then multiple-copy insert transformants were screened out and cultured in flasks, and hVEGF165 was expressed under the induction of 1% methanol. Results  SDS-PAGE showed that after being induced with 1% methanol for 4d, the expressed product existed in supernatant in the form of soluble molecule and contained 60% of total protein expressed. Western blot showed good antigenicity and specificity of expressed product. After being purified by Heparin-Sepharose CL6B affinity chromatography, the purity of expressed product reached above 90%. Biological assays proved that the expressed product could stimulate the proliferation of HUVEC. Conclusion  hVEGF165 was successfully expressed. The study opened up a wide prospect for the application of VEGF165 in the prevention and treatment of ischemic heart disease and other tissue ischemic diseases such as secondary arterial occlusion in limbs.

  1. Determining the factors associated with health research participation.

    Science.gov (United States)

    Gucciardi, Enza; Di Liao, Chen; Cameron, Jill I

    2010-01-01

    This study explores factors and attitudes that affect willingness to participate in health research in an ambulatory population of 175 individuals. Respondents reported on their sociodemographic characteristics and rated statements on a questionnaire regarding their likelihood to participate in and attitudes toward health research. Multivariate ordinal regression analysis revealed that having more positive and less negative attitudes toward health research, access to the Internet, previous participation experience, higher education, and being Canadian-born contribute to a greater willingness to participate in health research. Understanding factors that influence research participation can help identify and direct efforts to improve research volunteer recruitment. PMID:20539155

  2. Determination of polycyclic aromatic compounds and heavy metals in sludges from biological sewage treatment plants.

    Science.gov (United States)

    Bodzek, D; Janoszka, B; Dobosz, C; Warzecha, L; Bodzek, M

    1997-07-11

    The procedure of the analysis of polycyclic aromatic hydrocarbons (PAHs) and their derivatives in the sludges from biological sewage treatment plants has been worked out. The analysis included isolation of organic matter from sludges, separation of the extract into fractions of similar chemical character, qualitative-quantitative analysis of individual PAHs and their nitrogenated and oxygenated derivatives. Liquid-solid chromatography, solid-phase extraction and semipreparative band thin-layer chromatography techniques were used for the separation. Capillary gas chromatography-mass spectrometry analysis of the separated fractions enabled identification of more than 21 PAHs, including hydrocarbons which contained 2-6 aromatic rings as well as their alkyl derivatives, 10 oxygen derivatives, 9 nitroarenes, aminoarenes and over 20 azaarenes and carbazoles. Using the capillary gas chromatography-flame ionization detection technique the content of 17 dominant PAHs was determined. The content of heavy metals was determined in investigated sludges with the use of atomic absorption spectrometry. The concentrations of the respective metals could be ranked in the order Cd coal mine wastes, taking into consideration the contents of toxic organic pollutants and heavy metals. PMID:9253190

  3. A new kinetic spectrophotometric method for the determination of major metabolite of heroin in biological samples

    Institute of Scientific and Technical Information of China (English)

    M. Reza Shishehbore; Ali Sheibani; Ehsan Mirparizi

    2012-01-01

    This study describes a simple,rapid and selective catalytic kinetic spectrophotometric method for the determination of 6-monoacetylmorphine (6-MAM) as major metabolite of heroin in biological samples.The method is based upon the catalytic effect of 6-MAM on the oxidation of Janus Green by bromate in acid media.The reaction was followed spectrophotometrically by measuring the decrease in absorbance of Janus Green at 618 nm.The dependence of sensitivity on the reaction variables was studied.Under optimum conditions,two linear calibration curves over the range 0.1-1.0 μg mL-1 and 1.0-34.0 μg mL-1 of 6-MAM were obtained.The detection limit was 1.2 × 10-2 μg mL-1 of 6-MAM.The relative standard deviations for six replicate determinations of 0.8 and 5.0 μg mL 1 of 6-MAM were 1.4 and 1.1% respectively.The effect of various species commonly associated with heroin in real samples was also investigated.The proposed method was successfully applied in human urine and serum samples with satisfactory results.

  4. Application of ion mobility spectrometry for the determination of tramadol in biological samples

    Directory of Open Access Journals (Sweden)

    Ali Sheibani

    2014-12-01

    Full Text Available In this study, a simple and rapid ion mobility spectrometry (IMS method has been described for the determination of tramadol. The operating instrumental parameters that could influence IMS were investigated and optimized (temperature; injection: 220 and IMS cell: 190°C, flow rate; carrier: 300 and drift: 600 mL/minute, voltage; corona: 2300 and drift: 7000 V, pulse width: 100 μs. Under optimum conditions, the calibration curves were linear within two orders of magnitude with R2 ≥ 0.998 for the determination of tramadol in human plasma, saliva, serum, and urine samples. The limits of detection and the limits of quantitation were between 0.1 and 0.3 and 0.3 and 1 ng/mL, respectively. The relative standard deviations were between 7.5 and 8.8%. The recovery results (90–103.9% indicate that the proposed method can be applied for tramadol analysis in different biological samples.

  5. Factors affecting biological denitrifying dephosphatation in anaerobic/anoxic/aerobic sequencing batch reactor

    Institute of Scientific and Technical Information of China (English)

    2007-01-01

    This study was conducted to verify and discuss the denitrifying dephosphatation under different levels of nitrate concentration and retention time of anoxic/aerobic process in a Sequencing Batch Reactor ( SBR ).The results of tests demonstrated that there were two kinds of phosphorus-accumulating organisms (PAOs) in the biological excess phosphorus removal (BEPR) system. One was non-DNPAOs that could only use oxygen as terminal electron acceptors, the other was denitrifying PAOs (DNPAOs) that could use both nitrate and oxygen as terminal electron acceptors. Phosphorus uptake efficiency could be attained under anoxic period ranging from 28.7%-96.7% in an anacrobic/anoxic/aerobic system. Experimental results showed that nitrate concentration and retention time of anoxic/aerobic process were the key factors affecting the course of denitrifying dephosphatation.

  6. Chemical, Physical, and Biological Factors Influencing Nutrient Availability and Plant Growth in a Pine Tree Substrate

    OpenAIRE

    Jackson, Brian Eugene

    2008-01-01

    Pine tree substrate (PTS) produced from freshly harvested loblolly pine (Pinus taeda L.) trees has potential for replacing or reducing the use of aged pine bark (PB) and peat moss as container substrates for horticulture crop production. The objective of this work was to determine the factors influencing nutrient availability in PTS compared to PB or peat substrates. Chapter two reports data on the response of japanese holly and azalea to fertilizer rate when grown in PTS and PB. This stud...

  7. IMPROVEMENT SYSTEM OF BIOLOGICAL FACTORS MANAGEMENT IN THE BREEDING OF FARM ANIMALS

    Directory of Open Access Journals (Sweden)

    A. Shendakov

    2012-12-01

    Full Text Available Due to economical transformations of 1990-s in the sphere of milking cows breeding its profitability has grown low on many Russian cow-breeding farms, which was accompanied by the deterioration of zootechnical registration, selection and analytical approach to salvation of agro industrial complex topical problems. It caused the necessity of animal breeding enterprises reorganization. The introduction of intensive technologies, intellectual and methodical potential of domestic and foreign science to the animal breeding set a number of new problems before zootechnicians and stock-breeders. One of these tasks - improving the management of breeding and, especially, its biological factors (heritability, genetic correlations, the effect of heterosis, etc.. The situation is complicated by the fact that currently used in the selection of inbreeding, which often leads to inbreeding depression on intensity of growth, live weight, reproductive qualities and other selection signs. For the decision it is problems us researches of influence of inbreeding on efficiency of Black-and-White cows have been conducted. In scientific work the results of a comparative evaluation of milk yield of cows with inbreeding and conventional breeding. In the scientific is work studied the percentage of heifers and steers at calving, the number of calves-twins, stillborn calves and abortions in inbreeding and normal of animals groups. Inbreeding no had significant effect on stillbirths. The percentage of Holstein genes may influence of the sexes ratio in their offspring. The article presents the analysis of the level of development and the trends of production and selection in dairy cattle breeding, given prognosis for pig-breeding in Russia, a scheme of management of biological factors of selection, is work said about results of selection of Black-and-White, Simmental and Holstein cattle, also pig in Orel region.

  8. Determinants of Teacher Militancy: Factors Affecting the Decision to Strike.

    Science.gov (United States)

    Tomkiewicz, Joseph

    1979-01-01

    Statistical analysis of factors offered as explanations for teacher militancy demonstrates that they possess little value in differentiating striking from nonstriking school districts. Boards cannot depend on objective measures alone in preparing for negotiations and might better aim their efforts in other directions. (Author/IRT)

  9. What Factors Determine the Uptake of A-Level Physics?

    Science.gov (United States)

    Gill, Tim; Bell, John F.

    2013-01-01

    There has been much concern recently in the UK about the decline in the number of students studying physics beyond age 16. To investigate why this might be we used data from a national database of student qualifications and a multilevel modelling technique to investigate which factors had the greatest impact on the uptake of physics at Advanced…

  10. Study to Determine the Biological Feasibility of a New Fish Tagging System : Annual Report 1983.

    Energy Technology Data Exchange (ETDEWEB)

    Prentice, Earl F.; Park, D.L.

    1984-05-01

    Pacific salmon are tagged or marked as a critical part of numerous research and management studies. A new tag called the PIT (passive integrated transponder) tag measuring 7.5 mm long by 1.5 mm in diameter has a great potential for marking fish if it proves to be biologically compatible. A study was conducted to evaluate the potential of the PIT tag for marking salmonids. The objectives of the first year's research were to determine: (1) the anatomical areas in which the tag could be placed; (2) tissue response to the tag; and (3) tag retention. Juvenile coho, Oncorhynchus kisutch, and chinook O. tshawytscha, salmon and adult chinook salmon held at Manchester or Big Beef Creek, Washington, were used as test animals. Juvenile salmon were injected with sham PIT tags in the body cavity and opercular, dorsal, and caudal masculature. The fish ranged in length from 126 to 212 mm. Observations based on three tests, from 44 to 102 days long, indicated that the dorsal musculature and body cavity were the best locations to inject the tag from biological and social standpoints. Sham PIT tags were injected into the nose; body cavity; and opercular, dorsal, and caudal musculature of jack chinook salmon. The test was conducted for 23 days. Although all five anatomical areas were acceptable from a technical standpoint, the body cavity appeared to be the best area for tag placement. Initial test results with the Sham PIT tag were very encouraging. Apparently the PIT tag can be successfully injected into and carried by salmon, making it a potentially useful tool for fisheries biologists. 5 refs., 8 figs., 6 tabs.

  11. NEW DETERMINANT FACTORS OF CHANGE MANAGEMENT IN THE HOSPITALITY INDUSTRY

    Directory of Open Access Journals (Sweden)

    Eugenia ALECU

    2013-12-01

    Full Text Available The factors that we took into account the following important elements: for goods and capital (brand promotion, reliable predictions against risk factors, knowledge capital, intangible values for hotels, for health and safety (the easily with which diseases can cross oceans and borders and multiplying rows of old and new infections, some impossible to treat, strict control of food and non-food products entering in the hotel, for new management (planning education and training process in hospitality industry, demographic problem, New trends in the workplace. One of the most dramatic changes in this industry is the way to sold products and services for public hotels. New technology, development of hospitality industry and social problems are very important, also in this process of change management to hotels.

  12. A study to determine influential factors on product positioning

    OpenAIRE

    Naser Azad; Neda Abbasi; Seyed Foad Zarifi

    2013-01-01

    Product positioning plays an important role on business development especially in food industry. In this paper, we perform an exploration study to find important factors influencing product positioning in Iranian food industry. The study designs a questionnaire in Likert scale and distributes it among 260 randomly selected people from food industry. Cronbach alpha has been calculated as 0.86 in preliminary stage and final 0.697 in final stage, which are statistically acceptable. The study use...

  13. Factors Determining Inpatient Satisfaction with Hospital Care in Bangladesh

    OpenAIRE

    Laila Ashrafun; Mohammad Jasim Uddin

    2011-01-01

    The objective of this study is to identify factors associated with satisfaction among inpatients receiving medical and surgical care for urinary, cardiovascular, respiratory, and ophthalmology diseases at Dhaka Government Medical College Hospital, Bangladesh. The data of this study is collected from 190 inpatients by using a patient judgments questionnaire covering 10 dimensions of satisfaction (appointment waiting time for doctor after admission, doctor’s treatment and behavior, behavior and...

  14. Factors Determining Awareness and Knowledge of Aquatic Invasive Species

    NARCIS (Netherlands)

    Eiswerth, M.E.; Yen, S.T.; Kooten, van G.C.

    2011-01-01

    Public perceptions of invasive species may influence policies and programs initiated by public and private stakeholders. We investigate the determinants of the public's awareness and knowledge of invasive species as few studies have examined this relationship. We focus on aquatic invasive species (A

  15. Determinant Factors of Physical Fitness in European Children

    DEFF Research Database (Denmark)

    Zaqout, Mahmoud; Vyncke, Krishna; Moreno, Luis A.;

    2016-01-01

    ’s fitness. Significant but small effects were found for low maternal BMI, high psychosocial well-being and fruit and vegetable intake as protective determinants. Sleep duration, breakfast intake, parental age and education and paternal BMI did not have a consistently significant effect on physical fitness...

  16. Analysis of transfer reactions: determination of spectroscopic factors

    Energy Technology Data Exchange (ETDEWEB)

    Keeley, N. [CEA Saclay, Dept. d' Astrophysique, de Physique des Particules de Physique Nucleaire et de l' Instrumentation Associee (DSM/DAPNIA/SPhN), 91- Gif sur Yvette (France); The Andrzej So an Institute for Nuclear Studies, Dept. of Nuclear Reactions, Warsaw (Poland)

    2007-07-01

    An overview of the most popular models used for the analysis of direct reaction data is given, concentrating on practical aspects. The 4 following models (in order of increasing sophistication): the distorted wave born approximation (DWBA), the adiabatic model, the coupled channels born approximation, and the coupled reaction channels are briefly described. As a concrete example, the C{sup 12}(d,p)C{sup 13} reaction at an incident deuteron energy of 30 MeV is analysed with progressively more physically sophisticated models. The effect of the choice of the reaction model on the spectroscopic information extracted from the data is investigated and other sources of uncertainty in the derived spectroscopic factors are discussed. We have showed that the choice of the reaction model can significantly influence the nuclear structure information, particularly the spectroscopic factors or amplitudes but occasionally also the spin-parity, that we wish to extract from direct reaction data. We have also demonstrated that the DWBA can fail to give a satisfactory description of transfer data but when the tenets of the theory are fulfilled DWBA can work very well and will yield the same results as most sophisticated models. The use of global rather than fitted optical potentials can also lead to important differences in the extracted spectroscopic factors.

  17. Modulation of circulating angiogenic factors and tumor biology by aerobic training in breast cancer patients receiving neoadjuvant chemotherapy.

    Science.gov (United States)

    Jones, Lee W; Fels, Diane R; West, Miranda; Allen, Jason D; Broadwater, Gloria; Barry, William T; Wilke, Lee G; Masko, Elisabeth; Douglas, Pamela S; Dash, Rajesh C; Povsic, Thomas J; Peppercorn, Jeffrey; Marcom, P Kelly; Blackwell, Kimberly L; Kimmick, Gretchen; Turkington, Timothy G; Dewhirst, Mark W

    2013-09-01

    Aerobic exercise training (AET) is an effective adjunct therapy to attenuate the adverse side-effects of adjuvant chemotherapy in women with early breast cancer. Whether AET interacts with the antitumor efficacy of chemotherapy has received scant attention. We carried out a pilot study to explore the effects of AET in combination with neoadjuvant doxorubicin-cyclophosphamide (AC+AET), relative to AC alone, on: (i) host physiology [exercise capacity (VO2 peak), brachial artery flow-mediated dilation (BA-FMD)], (ii) host-related circulating factors [circulating endothelial progenitor cells (CEP) cytokines and angiogenic factors (CAF)], and (iii) tumor phenotype [tumor blood flow ((15)O-water PET), tissue markers (hypoxia and proliferation), and gene expression] in 20 women with operable breast cancer. AET consisted of three supervised cycle ergometry sessions/week at 60% to 100% of VO2 peak, 30 to 45 min/session, for 12 weeks. There was significant time × group interactions for VO2 peak and BA-FMD, favoring the AC+AET group (P blood flow in the AC+AET group. There were no differences in any tumor tissue markers (P > 0.05). Whole-genome microarray tumor analysis revealed significant differential modulation of 57 pathways (P < 0.01), including many that converge on NF-κB. Data from this exploratory study provide initial evidence that AET can modulate several host- and tumor-related pathways during standard chemotherapy. The biologic and clinical implications remain to be determined. PMID:23842792

  18. Effects of transforming growth interacting factor on biological behaviors of gastric carcinoma cells

    Institute of Scientific and Technical Information of China (English)

    Zhong-Liang Hu; Ji-Fang Wen; De-Sheng Xiao; Hui Zhen; Chun-Yan Fu

    2005-01-01

    AIM:Transforming growth interacting factor (TGIF) is an inhibitor of both transforming growth factor β (TGF-β) and retinoid signaling pathways. Moreover, the activation of MAPK pathway can prolong its half-life. However, its role in carcinogenesis is still unknown. Thus we attempted to investigate the effect of TGIF on biologic behaviors of gastric carcinoma cells.METHODS: Gastric carcinoma cell line, SGC-7901, was stably transfected with plasmid PcDNA3.1-TGIF. Western blotting and cell immunohistochemistry screening for the highly expressing clone of TGIF were employed. The growth of transfected cells was investigated by MTT and colonyformation assays, and apoptosis was measured by flow cytometry (FCM) and transmission electron microscopy.Tumorigenicity of the transfectant cells was also analyzed.RESULTS: TGIF had no effect on the proliferation, cell cycle and apoptosis of SGC-7901 cells, but cellular organelles of cells transfected with TGIF were richer than those of vector control or parental cells. Its clones were smaller than the control ones in plate efficiency, and its tumor tissues also had no obvious necrosis compared with the vector control or parental cells. Moreover, TGIF could resist TGF-β mediated growth inhibition.CONCLUSION: TGIF may induce differentiation of stomach neoplastic cells. In addition, TGIF can counteract the growth inhibition induced by TGF-β.

  19. Production of feline leukemia inhibitory factor with biological activity in Escherichia coli.

    Science.gov (United States)

    Kanegi, R; Hatoya, S; Tsujimoto, Y; Takenaka, S; Nishimura, T; Wijewardana, V; Sugiura, K; Takahashi, M; Kawate, N; Tamada, H; Inaba, T

    2016-07-15

    Leukemia inhibitory factor (LIF) is a cytokine which is essential for oocyte and embryo development, embryonic stem cell, and induced pluripotent stem cell maintenance. Leukemia inhibitory factor improves the maturation of oocytes in the human and the mouse. However, feline LIF (fLIF) cloning and effects on oocytes during IVM have not been reported. Thus, we cloned complete cDNA of fLIF and examined its biological activity and effects on oocytes during IVM in the domestic cat. The aminoacid sequence of fLIF revealed a homology of 81% or 92% with that of mouse or human. The fLIF produced by pCold TF DNA in Escherichia coli was readily soluble and after purification showed bioactivity in maintaining the undifferentiated state of mouse embryonic stem cells and enhancing the proliferation of human erythrocyte leukemia cells. Furthermore, 10- and 100-ng/mL fLIF induced cumulus expansion with or without FSH and EGF (P reproduction and stem cell research in the feline family. PMID:27020881

  20. Determinants of the exclusive breastfeeding abandonment: psychosocial factors

    OpenAIRE

    Mariana Campos Martins Machado; Karine Franklin Assis; Fabiana de Cássia Carvalho Oliveira; Andréia Queiroz Ribeiro; Raquel Maria Amaral Araújo; Alexandre Faisal Cury; Silvia Eloiza Priore; Sylvia do Carmo Castro Franceschini

    2014-01-01

    OBJECTIVE To assess the determinants of exclusive breastfeeding abandonment. METHODS Longitudinal study based on a birth cohort in Viçosa, MG, Southeastern Brazil. In 2011/2012, 168 new mothers accessing the public health network were followed. Three interviews, at 30, 60, and 120 days postpartum, with the new mothers were conducted. Exclusive breastfeeding abandonment was analyzed in the first, second, and fourth months after childbirth. The Edinburgh Postnatal Depression Scale was applied...

  1. [Determination of von Willebrand factor multimers in Mexican population].

    Science.gov (United States)

    Hernández-Zamora, Edgar; Zavala-Hernández, Cesar; Viveros-Sandoval, Martha Eva; Ochoa-Rico, Angeles; Martínez-Murillo, Carlos; Reyes-Maldonado, Elba

    2014-01-01

    Antecedentes: la enfermedad de von Willebrand es un padecimiento hereditario en el que la estructura, función y concentración del factor de von Willebrand están alteradas y, en consecuencia, también la interacción plaqueta-factor de von Willebrand-endotelio. En México no hay registros epidemiológicos de la enfermedad, sólo se han efectuado algunos estudios aislados desde el punto de vista clínico y hematológico. Material y métodos: estudio retrospectivo efectuado en 155 mexicanos mestizos, 75 de ellos con diagnóstico presuntivo de enfermedad de von Willebrand, 15 con sospecha de hemofilia A y 65 donadores sanos (testigos). Se realizaron pruebas: básicas de coagulación, especiales y de clasificación: análisis de la composición multimérica. Resultados: 15 pacientes se diagnosticaron con hemofilia A; de los 75 sujetos con sospecha de enfermedad de von Willebrand se diagnosticaron 50 de la manera siguiente: tipo 1 (62%), tipo 2 (22%) [subtipos: 2A (14%), 2B (2%) y 2N (6%)] y tipo 3 (16%). Conclusión: el análisis de los multímeros del factor de von Willebrand es un método que cumple con las características adecuadas para el diagnóstico de la enfermedad de von Willebrand, por lo que es necesario implementar esta metodología para su estudio y mejorar su diagnóstico específico.

  2. Determination of selectivity of HPLC systems by correspondence factor analysis

    Institute of Scientific and Technical Information of China (English)

    Yuan Wang; Jun Yang; Xin Lu; Guo Wang Xu

    2007-01-01

    Correspondence factor analysis (CFA) was employed to study the selectivity of 14 HPLC systems, The tested LC systems were classified as reversed-phase (RP), ion-exchange (IE) and hydrophilic interaction chromatography (HILIC) modes. It was found that the retentions of the hydrophilic solutes on HILIC column were significantly influenced by the second-order effects besides their hydrophilic properties. Organic modifiers and residue silanol groups on silica surface both participated in retention. HypersilTM amino column performed separation in the HILIC mode at appropriate conditions, and its retention mechanism was more similar to that of HILIC silica column than that of HILIC column coating poly(aspartamide) groups.

  3. Network motif-based identification of transcription factor-target gene relationships by integrating multi-source biological data

    Directory of Open Access Journals (Sweden)

    de los Reyes Benildo G

    2008-04-01

    Full Text Available Abstract Background Integrating data from multiple global assays and curated databases is essential to understand the spatio-temporal interactions within cells. Different experiments measure cellular processes at various widths and depths, while databases contain biological information based on established facts or published data. Integrating these complementary datasets helps infer a mutually consistent transcriptional regulatory network (TRN with strong similarity to the structure of the underlying genetic regulatory modules. Decomposing the TRN into a small set of recurring regulatory patterns, called network motifs (NM, facilitates the inference. Identifying NMs defined by specific transcription factors (TF establishes the framework structure of a TRN and allows the inference of TF-target gene relationship. This paper introduces a computational framework for utilizing data from multiple sources to infer TF-target gene relationships on the basis of NMs. The data include time course gene expression profiles, genome-wide location analysis data, binding sequence data, and gene ontology (GO information. Results The proposed computational framework was tested using gene expression data associated with cell cycle progression in yeast. Among 800 cell cycle related genes, 85 were identified as candidate TFs and classified into four previously defined NMs. The NMs for a subset of TFs are obtained from literature. Support vector machine (SVM classifiers were used to estimate NMs for the remaining TFs. The potential downstream target genes for the TFs were clustered into 34 biologically significant groups. The relationships between TFs and potential target gene clusters were examined by training recurrent neural networks whose topologies mimic the NMs to which the TFs are classified. The identified relationships between TFs and gene clusters were evaluated using the following biological validation and statistical analyses: (1 Gene set enrichment

  4. Mercury speciation and total trace element determination of low-biomass biological samples.

    Science.gov (United States)

    Taylor, Vivien F; Jackson, Brian P; Chen, Celia Y

    2008-12-01

    Current approaches to mercury speciation and total trace element analysis require separate extraction/digestions of the sample. Ecologically important aquatic organisms--notably primary consumers such as zooplankton, polychaetes and amphipods--usually yield very low biomass for analysis, even with significant compositing of multiple organisms. Individual organisms in the lower aquatic food chains (mussels, snails, oysters, silversides, killifish) can also have very low sample mass, and analysis of whole single organisms is important to metal uptake studies. A method for the determination of both methyl Hg and total heavy metal concentrations (Zn, As, Se, Cd, Hg, Pb) in a single, low-mass sample of aquatic organisms was developed. Samples (2 to 50 mg) were spiked with enriched with (201)MeHg and (199)Hg, then leached in 4 M HNO(3) at 55 degrees C for extraction of MeHg. After 16 h, an aliquot (0.05 mL) was removed to determine mercury species (methyl and inorganic Hg) by isotope dilution gas chromatography inductively coupled plasma mass spectrometry (ICP-MS). The leachate was then acidified to 9 M HNO(3) and digested in a microwave at 150 degrees C for 10 min, and total metal concentrations were determined by collision cell ICP-MS. The method was validated by analyzing five biological certified reference materials. Average percent recoveries for Zn, As, Se, Cd, MeHg, Hg(total) and Pb were 99.9%, 103.5%, 100.4%, 103.3%, 101%, 97.7%, and 97.1%, respectively. The correlation between the sum of MeHg and inorganic Hg from the speciation analysis and total Hg by conventional digestion of the sample was determined for a large sample set of aquatic invertebrates (n = 285). Excellent agreement between the two measured values was achieved. This method is advantageous in situations where sample size is limited, and where correlations between Hg species and other metals are required in the same sample. The method also provides further validation of speciation data, by

  5. Separation Scheme for the Determination of Nine Elements in Biological Material

    International Nuclear Information System (INIS)

    A separation scheme is presented for the determination of nine trace elements in biological samples that give rise to long-lived gamma-emitting isotopes by neutron irradiation, namely silver, molybdenum, mercury, gold, chromium, cobalt, selenium, iron and zinc. The organic material is destroyed by combustion with oxygen in a flask according to Schöniger in the presence of 100 μg of carrier of each element. The ignition is electrical and provides an easy and safe method for burning the samples and avoiding losses of volatile elements. The combustion products are collected in HNO3-H2O2 - solution. Carrier yields of at least 98% were obtained in tracer experiments, except for gold and silver. At high temperatures these elements apparently form an Au-Pt and Ag-Pt alloy with the platinum combustion catalyst. Boiling the platinum sample holder with a few millilitres of aqua regia results in a quantitative recovery of both elements. The HNO3-H2O2 solution is evaporated to dryness and re dissolved in 2N HF. A number of trace elements are adsorbed on a Dowex 1-X8 column and eluted successively with 9N HCl, 1.2N HCl, 8N HNO3 + 4N NH4NO3 and 10% thiourea. A quantitative séparation is thus obtained of Ag, Mo, Hg and Au. Cr, Co, Se, Fe and Zn are not absorbed in 2N HF. This eluate is adsorbed on a second Dowex 1-X8 column in ION HCl and eluated successively with ION HCl, 3N HCl, 0.4N HCl and H2O. Fractions of Cr, Co + Se, Fe and Zn are obtained. A quantitative separation of Co from Se can be achieved on Dowex 50W-X4 in HCl. The volumes in which the individual elements are quantitatively collected are smaller than 30 ml. Consequently a relatively high counting efficiency can be achieved in a 25-ml well-type crystal. Quantitative recovery for all elements is obtained except for mercury and gold. Mercury losses occur on evaporating the HNO3-H2O2 mixture. As a suitable method for the determination of the mercury yield, dithizone titration was chosen. The yield of gold is

  6. Are interest groups different in the factors determining landscape preferences?

    Directory of Open Access Journals (Sweden)

    Maria Bacher

    2016-02-01

    Full Text Available In the last decades, rural landscape in Europe has evolved from an agricultural by-product to an important public good. This development creates not only new challenges to farming practices, it also makes participation and public involvement an indispensable tool for sustainable landscape planning. This is especially true for many European mountain regions, where tourism represents an important source of income and conflicts between locals’ and tourists’ interests should be avoided. In our study, we analyze whether discrepancies in the perception of the Alpine landscape can be located between locals and tourists and, if these differences exist, in which aspects these two groups are differing. A model employing three general factors able to describe landscape preferences regardless of the personal background is suggested and validated by confirmatory factor analysis. Our major finding shows that an attractive landscape for tourists does not have to be contradictory to a landscape that supports a high living quality for locals. Compromises in landscape planning between locals’ and tourists’ requirements seem often not to be necessary as they, generally, do not differ in the way they experience and assess the landscape.

  7. Factors that determine the evolution of high-growth businesses

    Directory of Open Access Journals (Sweden)

    Oriol Amat

    2013-09-01

    Full Text Available Objective: The study herein discusses research aimed at elucidating the factors that contribute to a business’ ability to maintain high growth. Design/Methodology/Perspective: The database from the Iberian Balance Sheet Analysis System (SABI, from its initials in Spanish was used to identify 250 industrial Catalonian businesses with high growth during 2004-2007. These companies participated in a survey on strategies and management practices; in 2013, they were re-analyzed to investigate the factors that contributed to continued growth for certain companies. Contributions: Through diverse statistical techniques, business policies related to quality, innovation, internationalization and finance were shown to influence business growth and sustainability over time. Limitations of the Research: This study focuses on industrial businesses at least ten years old in Catalonia; thus, the conclusions may differ in other geographic locations and economic sectors, as well as for smaller businesses. Practical Implications: Because growth is a measure of business success, identifying variables that contribute to high growth and its sustainability is helpful for businesses that seek to adopt effective policies. Social Implications: Generating employment is one of the primary contributions by high-growth businesses. For years with high unemployment, authorities may be interested in corporate policies that strengthen high-growth businesses. Originality/Added Value: High-growth businesses have been studied throughout the world, but this is the first study to investigate the evolution of businesses after a high-growth phase.

  8. Variation in salamander tail regeneration is associated with genetic factors that determine tail morphology.

    Directory of Open Access Journals (Sweden)

    Gareth J Voss

    Full Text Available Very little is known about the factors that cause variation in regenerative potential within and between species. Here, we used a genetic approach to identify heritable genetic factors that explain variation in tail regenerative outgrowth. A hybrid ambystomatid salamander (Ambystoma mexicanum x A. andersoni was crossed to an A. mexicanum and 217 offspring were induced to undergo metamorphosis and attain terrestrial adult morphology using thyroid hormone. Following metamorphosis, each salamander's tail tip was amputated and allowed to regenerate, and then amputated a second time and allowed to regenerate. Also, DNA was isolated from all individuals and genotypes were determined for 187 molecular markers distributed throughout the genome. The area of tissue that regenerated after the first and second amputations was highly positively correlated across males and females. Males presented wider tails and regenerated more tail tissue during both episodes of regeneration. Approximately 66-68% of the variation in regenerative outgrowth was explained by tail width, while tail length and genetic sex did not explain a significant amount of variation. A small effect QTL was identified as having a sex-independent effect on tail regeneration, but this QTL was only identified for the first episode of regeneration. Several molecular markers significantly affected regenerative outgrowth during both episodes of regeneration, but the effect sizes were small (<4% and correlated with tail width. The results show that ambysex and minor effect QTL explain variation in adult tail morphology and importantly, tail width. In turn, tail width at the amputation plane largely determines the rate of regenerative outgrowth. Because amputations in this study were made at approximately the same position of the tail, our results resolve an outstanding question in regenerative biology: regenerative outgrowth positively co-varies as a function of tail width at the amputation site.

  9. Granulocyte macrophage colony stimulating factor (GM-CSF biological actions on human dermal fibroblasts

    Directory of Open Access Journals (Sweden)

    S Montagnani

    2009-12-01

    Full Text Available Fibroblasts are involved in all pathologies characterized by increased ExtraCellularMatrix synthesis, from wound healing to fibrosis. Granulocyte Macrophage-Colony Stimulating Factor (GM-CSF is a cytokine isolated as an hemopoietic growth factor but recently indicated as a differentiative agent on endothelial cells. In this work we demonstrated the expression of the receptor for GM-CSF (GMCSFR on human normal skin fibroblasts from healthy subjects (NFPC and on a human normal fibroblast cell line (NHDF and we try to investigate the biological effects of this cytokine. Human normal fibroblasts were cultured with different doses of GM-CSF to study the effects of this factor on GMCSFR expression, on cell proliferation and adhesion structures. In addition we studied the production of some Extra-Cellular Matrix (ECM components such as Fibronectin, Tenascin and Collagen I. The growth rate of fibroblasts from healthy donors (NFPC is not augmented by GM-CSF stimulation in spite of increased expression of the GM-CSFR. On the contrary, the proliferation of normal human dermal fibroblasts (NHDF cell line seems more influenced by high concentration of GM-CSF in the culture medium. The adhesion structures and the ECM components appear variously influenced by GM-CSF treatment as compared to fibroblasts cultured in basal condition, but newly only NHDF cells are really induced to increase their synthesis activity. We suggest that the in vitro treatment with GM-CSF can shift human normal fibroblasts towards a more differentiated state, due or accompanied by an increased expression of GM-CSFR and that such “differentiation” is an important event induced by such cytokine.

  10. Determination of hydroxyurea in capsules and biological fluids by ion-selective potentiometry and fluorimetry.

    Science.gov (United States)

    El-Kosasy, Amira M

    2003-01-01

    Two hydroxyurea selective electrodes were investigated with beta-cyclodextrin used as ionophore and either tetrakis (p-chlorophenyl) borate (electrode 1), or tetrakis [3,4-bis (trifluoromethyl) phenyl] borate (electrode 2), as a fixed anionic site in a polymeric matrix of carboxylated polyvinyl chloride. Linear responses of hydroxyurea within a concentration range of 10(-5)-10(-)3 M with slopes of 51.2 and 58.6 mV/decade with pH 3-6 were obtained by using electrodes 1 and 2, respectively. Two spectrofluorimetric methods involving the formation of drug-AI(III) complex (method 3) and drug-Mg(II) complex (method 4) at pH 5 were also investigated. These complexes emit fluorescence at wavelengths of 380 and 355 nm, after excitation at 305 nm, for AI and Mg complexes, respectively. The calibration graphs were rectilinear from 0.5 to 2.5 microg/mL for the AI complex and 1 to 5 microg/mL for the Mg complex. The 4 proposed methods display useful analytical characteristics for determination of hydroxyurea, with average recoveries of 100.2 +/- 0.83 and 99.4 +/- 1.81% in capsules and 99.7 +/- 0.70 and 99.4 +/- 1.25% in biological fluids for the potentiometric and fluorimetric methods, respectively. Results obtained by the proposed procedures were statistically analyzed and compared with those obtained by the U.S. Pharmacopeial method. The 4 proposed procedures were also used to determine the stability of the drug in the presence of its degradate, hydroxylamine.

  11. Two-Dimensional Flow Nanometry of Biological Nanoparticles for Accurate Determination of Their Size and Emission Intensity

    CERN Document Server

    Block, Stephan; Lundgren, Anders; Zhdanov, Vladimir P; Höök, Fredrik

    2016-01-01

    Biological nanoparticles (BNPs) are of high interest due to their key role in various biological processes and use as biomarkers. BNP size and molecular composition are decisive for their functions, but simultaneous determination of both properties with high accuracy remains challenging, which is a severe limitation. Surface-sensitive microscopy allows one to precisely determine fluorescence or scattering intensity, but not the size of individual BNPs. The latter is better determined by tracking their random motion in bulk, but the limited illumination volume for tracking this motion impedes reliable intensity determination. We here show that attaching BNPs (specifically, vesicles and functionalized gold NPs) to a supported lipid bilayer, subjecting them to a hydrodynamic flow, and tracking their motion via surface-sensitive imaging enable to determine their diffusion coefficients and flow-induced drift velocities and to accurately quantify both BNP size and emission intensity. For vesicles, the high accuracy...

  12. Biological activity of the virulence factor cagA of Helicobacter pylori

    Institute of Scientific and Technical Information of China (English)

    朱永良; 郑树; 钱可大; 方平楚

    2004-01-01

    Background China is one of the countries with the highest incidence of H. Pylori and more than 9090 isolates possessed the cagA gene. This study was to evaluate the biological activity of the H.pylori virulence factor cagA isolated from Chinese patients. Methods cagA DNA fragments were amplified from the genomic DNA and subsequently cloned into the mammalian expression vector for cell transfection and DNA sequencing. cagA protein, phosphorylated-tyrosine cagA and the complex of cagA precipitated with SHP-2 were identified respectively by western blot in the crude cell lysate from conditionally immortalized gastric epithelial cells at 48 hours after transfection with cagA DNA. In addition, the ability of induction of scattering phenotype was examined after transient expression of cagA in AGS cells. Results The C-terminal half of cagA contained only one repeated sequence and three tandem five-amino-acid motifs glutamic acid-proline-isoleucine-tyrosine-alanine (EPIYA). Moreover, the amino acid sequence of D2 region in repeated sequence was aspartic acid-phenylanaline-aspartic acid (D-F-D) which was significantly distinguished from the three repeated sequences and aspartic acid-aspartic adid-leucine (D-D-L) in the western standard strain NCTC11637. Western blot revealed that cagA became phosphorylated in tyrosine site and bound with SHP-2 after transient expression of cagA DNA in gastric epithelial cells. Transient expression of cagA in AGS cells showed that cagA was able to induce the elongation phenotype although to a lesser extent than western strains. Conclusions cagA perturbs cell signaling pathways by binding with SHP-2. However, significant difference exists in amino acid sequence and biological function of cagA in Chinese compared with those of western countries.

  13. Dietary and microbiome factors determine longevity in Caenorhabditis elegans

    Science.gov (United States)

    Sánchez-Blanco, Adolfo; Rodríguez-Matellán, Alberto; González-Paramás, Ana; González-Manzano, Susana; Kim, Stuart K.; Mollinedo, Faustino

    2016-01-01

    Diet composition affects organismal health. Nutrient uptake depends on the microbiome. Caenorhabditis elegans fed a Bacillus subtilis diet live longer than those fed the standard Escherichia coli diet. Here we report that this longevity difference is primarily caused by dietary coQ, an antioxidant synthesized by E. coli but not by B. subtilis. CoQ-supplemented E. coli fed worms have a lower oxidation state yet live shorter than coQ-less B. subtilis fed worms. We showed that mutations affecting longevity for E. coli fed worms do not always lead to similar effects when worms are fed B. subtilis. We propose that coQ supplementation by the E. coli diet alters the worm cellular REDOX homeostasis, thus decreasing longevity. Our results highlight the importance of microbiome factors in longevity, argue that antioxidant supplementation can be detrimental, and suggest that the C. elegans standard E. coli diet can alter the effect of signaling pathways on longevity. PMID:27510225

  14. Influence of Biological Factors on Connectivity Patterns for Concholepas concholepas (loco) in Chile

    Science.gov (United States)

    Garavelli, Lysel; Colas, François; Verley, Philippe; Kaplan, David Michael; Yannicelli, Beatriz; Lett, Christophe

    2016-01-01

    In marine benthic ecosystems, larval connectivity is a major process influencing the maintenance and distribution of invertebrate populations. Larval connectivity is a complex process to study as it is determined by several interacting factors. Here we use an individual-based, biophysical model, to disentangle the effects of such factors, namely larval vertical migration, larval growth, larval mortality, adults fecundity, and habitat availability, for the marine gastropod Concholepas concholepas (loco) in Chile. Lower transport success and higher dispersal distances are observed including larval vertical migration in the model. We find an overall decrease in larval transport success to settlement areas from northern to southern Chile. This spatial gradient results from the combination of current direction and intensity, seawater temperature, and available habitat. From our simulated connectivity patterns we then identify subpopulations of loco along the Chilean coast, which could serve as a basis for spatial management of this resource in the future. PMID:26751574

  15. Influence of Biological Factors on Connectivity Patterns for Concholepas concholepas (loco) in Chile.

    Science.gov (United States)

    Garavelli, Lysel; Colas, François; Verley, Philippe; Kaplan, David Michael; Yannicelli, Beatriz; Lett, Christophe

    2016-01-01

    In marine benthic ecosystems, larval connectivity is a major process influencing the maintenance and distribution of invertebrate populations. Larval connectivity is a complex process to study as it is determined by several interacting factors. Here we use an individual-based, biophysical model, to disentangle the effects of such factors, namely larval vertical migration, larval growth, larval mortality, adults fecundity, and habitat availability, for the marine gastropod Concholepas concholepas (loco) in Chile. Lower transport success and higher dispersal distances are observed including larval vertical migration in the model. We find an overall decrease in larval transport success to settlement areas from northern to southern Chile. This spatial gradient results from the combination of current direction and intensity, seawater temperature, and available habitat. From our simulated connectivity patterns we then identify subpopulations of loco along the Chilean coast, which could serve as a basis for spatial management of this resource in the future.

  16. Determining Factors of Lipophilic Micronutrient Bioaccessibility in Several Leafy Vegetables.

    Science.gov (United States)

    Sriwichai, Wichien; Berger, Jacques; Picq, Christian; Avallone, Sylvie

    2016-03-01

    Micronutrient deficiencies are still a public health issue in least developed countries. Promoting diet diversification is a promising strategy. Numerous fruits and vegetables are rich in micronutrients, but some of these compounds are poorly bioaccessible. The objective of this study was to identify the biochemical determinants of the micronutrient bioaccessibility in leaves. The contents in cell walls, pectins, tannins, and proteins of the leafy vegetables were assessed, and correlations with the micronutrient bioaccessibitity were explored. The leafy vegetables have interesting nutritional profiles with noticeable amounts in protein, provitamin A (β-carotene), and α-tocopherol for some species. Their cell wall contents greatly varied from 3.4 to 8.7 g/100 g as well as their pectin percentages. Only the perilla and drumstick leaves contained condensed tannins. In fresh leaves, the contents in bioaccessible carotenoids were low. The correlation study highlighted that the carotenoid bioaccessibility was negatively correlated to the pectin contents of the leaves.

  17. Factors determining accumulation of mycotoxin producers in cereal grain during harvesting.

    Science.gov (United States)

    Lugauskas, Albinas; Raila, Algirdas; Zvicevicius, Egidijus; Railiene, Marija; Novosinskas, Henrikas

    2007-01-01

    During the meteorologically contrasting period of 2003-2005, the contamination of winter wheat, malt barley and fodder barley grain with micromycetes during grain harvesting and preparation for storage was investigated. Micromycetes of over 70 species ascribed to 16 genera were isolated and identified, the density of their populations in grain was determined. Micromycetes with a population density of >50% were attributed to dominant species. Short biological characteristic, ecological peculiarities of the dominating micromycetes are provided; factors determining intensity of their development and abilities to synthesise and excrete toxic metabolites are indicated. The importance of grain drying for stabilisation of its contamination with micromycete propagules is highlighted. It is noted that in grain dried in shaft dryer using air at 90 degrees C the number of cfu (colony forming units) was reduced from 2.2 to 8.2 times. When active ventilation is applied, conditions favourable for the development of micromycetes remain longest in the upper layers of the mound. The airflow passing through the layer of damp grain inhibits the development of micromycetes, but an increase of comparative air flow for more than 500 m3x(txh)(-1) did not reduce the abundance of micromycete cfu. After drying Alternaria alternata, Fusarium avenaceum, F. culmorum, Penicillum verrucosum dominated in wheat grain; Aspergillus flavus, Bipolaris sorokiniana, Fusarium chlamydosporum, F. culmorum, F. tricinctum in malts barley grain; Fusarium avenaceum, F. culmorum, F. tricinctum, Alternaria alternata in fodder barley grain. It has been determined that all micromycetes recorded on grain after drying are potential producers of toxic metabolites, i.e. are hazardous to human health.

  18. The key factor determining the anodic deposition of vanadium oxides

    International Nuclear Information System (INIS)

    This work demonstrates that anodic deposition of vanadium oxide (denoted as VOx.nH2O) can be considered as the chemical co-precipitation of V5+ and V4+ oxy-/hydroxyl species and the accumulation of V5+ species at the vicinity of electrode surface is the key factor for the successful anodic deposition of VOx.nH2O at a potential much more negative than the equilibrium potential of the oxygen evolution reaction (OER). The results of in situ UV-vis spectra show that the V4+/V5+ ratio near the electrode surface can be controlled by varying the applied potential, leading to different, three-dimensional (3D) nanostructures of VOx.nH2O. The accumulation of V5+ species due to V4+ oxidation at potentials ≥0.4 V (vs. Ag/AgCl) has been found to be very similar to the phenomenon by adding H2O2 in the deposition solution. The X-ray photoelectron spectroscopic (XPS) results show that all VOx.nH2O deposits can be considered as aggregates consisting of mixed V5+ and V4+ oxy-/hydroxyl species with the mean oxidation state significantly increasing with the applied electrode potential.

  19. Determinant factors of industrial symbiosis: greening Pasir Gudang industrial park

    Science.gov (United States)

    Teh, B. T.; Ho, C. S.; Matsuoka, Y.; Chau, L. W.; Gomi, K.

    2014-02-01

    Green industry has been identified as an important element in attaining greater sustainability. It calls for harmonizing robust economic growth with environment protection. Industries, particularly in developing and transitional nations such as Malaysia, are in need of a reform. Many experts and international organizations suggest the concept of industrial symbiosis. Mainly, there are successful cases of industrial symbiosis practices around the world. However, there are numerous cases of failure too. As industrial symbiosis is an emerging new approach, with a short history of two decades, a lot of researches are generally focused on narrow context and technical details. There is a lack of concerted efforts to look into the drivers and barriers of industrial symbiosis across different cases. This paper aims to examine the factors influencing the development of industrial symbiosis from various countries to supports such networks to evolve in Pasir Gudang. The findings show institution, law and regulation, finance, awareness and capacity building, technology, research and development, information, collaboration, market, geography proximity, environmental issues and industry structure affect the formation of industrial symbiosis.

  20. Sensitive ergotamine determination in pharmaceuticals and biological samples using cloud point preconcentration and spectrofluorimetric detection.

    Science.gov (United States)

    Wang, Chien C; Fernández, Liliana P; Gómez, María Roxana

    2013-03-20

    A new cloud point extraction (CPE) method for ergotamine analysis using fluorimetric detection is described. Ergotamine from an aqueous solution was preconcentrated into a smaller surfactant-rich phase using nonionic surfactant polyoxyethylene(7.5)nonylphenylether (PONPE 7.5). Differently from the conventional CPE procedure in which the resulting surfactant-rich phase is diluted by a fluidificant before its analysis, in this method the fluorescence measurements were carried out directly onto the undiluted surfactant-rich phase. The high viscosity provided by the undiluted surfactant rich phase greatly improved the fluorescence emission of ergotamine, leading to a total enhancement factor of 1325. This spectral advantage plus the preconcentration factor achieved, contributed to the method sensitivity allowing the ergotamine determination at trace level concentration. Under optimal experimental conditions, a linear calibration curve was obtained from 3.81×10(-7) to 1.10μgmL(-1), with detection and quantification limits of 0.11 and 0.38pgmL(-1), respectively. The accuracy and versatility of the present methodology were proved by analyzing ergotamine in real samples of different natures such as pharmaceuticals, urine and saliva. PMID:23473254

  1. Psychological, social and biological determinants of ill health (pSoBid: Study Protocol of a population-based study

    Directory of Open Access Journals (Sweden)

    McGinty Agnes

    2008-04-01

    Full Text Available Abstract Background Disadvantaged communities suffer higher levels of physical and mental ill health than more advantaged communities. The purpose of the present study was to examine the psychosocial, behavioural and biological determinants of ill health within population groups in Glasgow that differed in socioeconomic status and in their propensity to develop chronic disease especially coronary heart disease and Type 2 diabetes mellitus. Methods Participants were selected at random from areas known to be at the extremes of the socioeconomic continuum in Glasgow. Within the categories of least deprived and most deprived, recruitment was stratified by sex and age to achieve an overall sample containing approximately equal numbers of males and females and an even distribution across the age categories 35–44, 45–54 and 55–64 years. Individuals were invited by letter to attend for assessment of their medical history, risk factor status, cognitive function and psychological profile, morbidity, and carotid intima-media thickness and plaque count as indices of atherosclerosis. Anonymised data on study subjects were collected from the General Practice Administration System for Scotland to analyse characteristics of participants and non-participants. Results 700 subjects were recruited. The response (active participants per 100 invitation letters in the least deprived group was 35.1% and in the most deprived group was 20.3%. Lowest response was seen in young males (least deprived 22.4% and most deprived 14.1%. Conclusion This cross-sectional study recruited the planned sample of subjects from least deprived and most deprived areas within Glasgow. As evident in other studies response differed between the most and least deprived areas. This study brought together researchers/academics from diverse disciplines to build a more sophisticated understanding of the determinants of health inequalities than can be achieved through unidisciplinary approaches

  2. Factors determining physical activity of Ukrainian students

    Directory of Open Access Journals (Sweden)

    Barbara Bergier

    2014-09-01

    Full Text Available [b]Objective[/b]. Scientific reports provide information concerning an insufficient level of physical activity of societies. The objective of the study is recognition of the level of physical activity among Ukrainian students, and factors which condition this activity: gender, place of residence, self-reported physical fitness, and the BMI. [b]Methods[/b]. The study was conducted in 2013 among 2,125 Ukrainian students using a long version of the International Physical Activity Questionnaire (IPAQ, supplemented with data concerning the respondents’ physical development. [b]Results[/b]. The results of the study showed that the mean total physical activity of students was 3.560 MET, and its highest percentage pertained to the area of activity in sports – 1.124 MET. Significantly higher statistically physical activity was observed among males than females. In males, the highest activity was related to participation in sports classes, while in females – engagement in household chores. It was found that males, compared to females, were significantly more physically active in such areas as occupational activity (education and sports activity, whereas females showed higher activity performing household chores. According to the place of residence, inhabitants of medium-size towns and rural areas obtained the most favourable results in activity, while the inhabitants of large cities the poorest. Self-reported physical fitness was significantly correlated with the results in physical activity obtained by the students. No relationship was found between the BMI and the level of student’s physical activity. [b]Conclusion[/b]. Considering the very large population of respondents, the results obtained may be considered as an up-to-date pattern of physical activity among Ukrainian students.

  3. Variation of Phenolic Content in Globe Artichoke in Relation to Biological, Technical and Environmental Factors

    Directory of Open Access Journals (Sweden)

    Giovanni Mauromicale

    2011-02-01

    Full Text Available In Italy, globe artichoke production is prevailingly concentrated in the South and islands, where it provides an important contribution to the agricultural economy. In recent years, there has been a renewed interest in this crop as a promising source of polyphenols, a heterogeneous class of secondary metabolites characterized by various healthy properties well-documented in literature. The phenolic fraction, present in the different artichoke plant parts, varies widely in relation to biotic and abiotic factors. Therefore, the present study aimed at evaluating the variation of phenolic content in globe artichoke in relation to biological, technical and environmental factors. Two field-experiments were carried out in Sicily (South Italy in two representative cultivation areas, in order to examine the effects of genotype, head fraction, season conditions, planting density and arrangement on the globe artichoke phenolic concentration. Both the total polyphenols and the individual phenolic compounds detected were notably genotype- dependent. Particularly, the high level of caffeoylquinic acids (chlorogenic acid, among others and apigenin 7- O-glucuronide, reported respectively by “Violetto di Sicilia” and “Romanesco clone C3”, could be used to encourage globe artichoke fresh consumption. Total polyphenols content also resulted more abundant in specific accumulation sites within the inflorescence, such as the floral stem and receptacle, and for most of genotypes it decreased during the second year in response to the different meteorological conditions. Additionally, total polyphenols content significantly and linearly increased as plant density increased from 1.0 to 1.8 plant m-2 and it significantly increased by 13% passing from single to twin rows plant arrangement.

  4. Modern methods for vancomycin determination in biological fluids by methods based on high-performance liquid chromatography--A review.

    Science.gov (United States)

    Javorska, Lenka; Krcmova, Lenka Kujovska; Solichova, Dagmar; Solich, Petr; Kaska, Milan

    2016-01-01

    Vancomycin is a glycopeptide antibiotic used in the therapy of severe bacterial infection. The monitoring of vancomycin levels is recommended because of its narrow therapeutic index and toxicity. This measurement is especially appropriate in patients with unstable renal functions, who receive high doses of vancomycin or present serious bacterial infections accompanied by important sequestration of liquids when it could be difficult to achieve the optimal therapeutic dose. Most of the methods for vancomycin determination in routine practice are immunoassays. However, chromatography-based techniques in combination with UV or mass spectrometry detection provide results with greater accuracy and precision also in complicated biological matrices. This review provides a detailed overview of modern approaches for the chromatographic separation of vancomycin in various biological samples and useful sample preparation procedures for vancomycin determination in various biological fluids.

  5. Circumventing furin enhances factor VIII biological activity and ameliorates bleeding phenotypes in hemophilia models

    Science.gov (United States)

    Siner, Joshua I.; Samelson-Jones, Benjamin J.; Crudele, Julie M.; French, Robert A.; Lee, Benjamin J.; Zhou, Shanzhen; Merricks, Elizabeth; Raymer, Robin; Camire, Rodney M.; Arruda, Valder R.

    2016-01-01

    Processing by the proprotein convertase furin is believed to be critical for the biological activity of multiple proteins involved in hemostasis, including coagulation factor VIII (FVIII). This belief prompted the retention of the furin recognition motif (amino acids 1645–1648) in the design of B-domain–deleted FVIII (FVIII-BDD) products in current clinical use and in the drug development pipeline, as well as in experimental FVIII gene therapy strategies. Here, we report that processing by furin is in fact deleterious to FVIII-BDD secretion and procoagulant activity. Inhibition of furin increases the secretion and decreases the intracellular retention of FVIII-BDD protein in mammalian cells. Our new variant (FVIII-ΔF), in which this recognition motif is removed, efficiently circumvents furin. FVIII-ΔF demonstrates increased recombinant protein yields, enhanced clotting activity, and higher circulating FVIII levels after adeno-associated viral vector–based liver gene therapy in a murine model of severe hemophilia A (HA) compared with FVIII-BDD. Moreover, we observed an amelioration of the bleeding phenotype in severe HA dogs with sustained therapeutic FVIII levels after FVIII-ΔF gene therapy at a lower vector dose than previously employed in this model. The immunogenicity of FVIII-ΔF did not differ from that of FVIII-BDD as a protein or a gene therapeutic. Thus, contrary to previous suppositions, FVIII variants that can avoid furin processing are likely to have enhanced translational potential for HA therapy. PMID:27734034

  6. Radiochemical method for the simultaneous determination of 233U, 236U, 237Np, 236Pu, 238Pu, and 239Pu in biological materials

    International Nuclear Information System (INIS)

    A radiochemical method has been developed for the determination of multiple isotopes of uranium, neptunium, and plutonium in biological materials. The elements are separated from the other sample constituents and from each other by anion exchange in halide media. Their recoveries are monitored by isotopic diluents. The amounts of the analyte and diluent isotopes of each element are measured alpha spectrometrically. The interelemental separation factors are generally greater than 102, and the recovery of each element ranges from 60% to 90%. 4 references, 1 table

  7. Ecological and biological determinants of methylmercury accumulation in tropical coastal fish.

    Science.gov (United States)

    Seixas, Tércia G; Moreira, Isabel; Malm, Olaf; Kehrig, Helena A

    2013-02-01

    This research investigated whether environmental conditions, biological fish characteristics and anthropogenic impacts influenced mercury (Hg) assimilation into the muscle tissue of two fish species from two Brazilian bays, Ilha Grande Bay and Guanabara Bay. Fish and superficial water were collected in different periods. Hg was determined by CV-AAS. Methylmercury (MeHg) was identified and quantified by ECD-GC. Chlorophyll a concentrations in the water column indicated that Ilha Grande Bay and Guanabara Bay were oligotrophic and eutrophic, respectively. Hg in fish ranged from 2.10 to 870.17 μg kg(-1) dry wt. in Ilha Grande Bay and 40.90 to 809.24 μg kg(-1) dry wt. in Guanabara Bay. Slight differences were found between the length-normalized Hg concentrations and its percent of Hg in a voracious predator from the bays. In Guanabara Bay, where the presence of a chlor-alkali plant causes Hg input, the iliophagous fish species showed the highest length-normalized Hg concentrations and the voracious predator the lowest. Iliophagous fish is consumed by voracious predator and, consequently, acts as their MeHg food supply. Iliophagous fish from Ilha Grande Bay presented a higher percent of MeHg (80.0 %) than specimens from Guanabara Bay (54.5 %). This fact suggests that more MeHg was transferred from iliophagous fish to voracious predator in Ilha Grande Bay. At Guanabara Bay, the bioproduction is greater than that at Ilha Grande Bay, presenting the highest biomass in it ecosystem, which may subsequently dilute Hg and reduce its availability to the biota; i.e., influencing in Hg and MeHg availability throughout the food chain. Consequently, more MeHg is available in the aquatic environment of Ilha Grande Bay.

  8. Factors determining the durability of steam superheater chambers

    Directory of Open Access Journals (Sweden)

    J. Lisok

    2008-11-01

    Full Text Available Purpose: The paper presents the results of calculations of effort for the material of selected superheater chambers’constructional systems in unsteady operation conditions.Design/methodology/approach: In model tests, the influence was analysed of internal pressure andtemperature gradient in the chamber wall on the distribution and value of stress . In the calculations, the processof hot start-up of a boiler was simulated, which was accompanied by short thermal shock induced by rapid coolingof the chamber inner wall.Findings: The random nature of thermal shock, which in the industrial practice may occur in any row and to anynumber of coil pipes, determines the value of maximal stress and the area of its occurrence. It has a significantinfluence on the possibility of forecasting the durability of chambers in working conditions.Research limitations/implications: The research has evidenced a link between the method of forcingthermal shock and the value of maximal stress in the area of bridges.Practical implications: The research has demonstrated the existence of connection between the way of forcingthermal shock and the stress value which, depending on the variant of cooling the chamber, ranges between150-370 MPa. These results are very important to the industry connected with the structure of pipelines.Originality/value: It was found that the primary reason for the superheater chamber damage, leading to crackformation, are thermal shocks. A link has been shown between the method of forcing the thermal shock and thevalue of maximal stress in the zone of bridges.

  9. Are autosomal sex-determining factors of the housefly (Musca domestica) spreading north?

    NARCIS (Netherlands)

    Kozielska, Magdalena; Feldmeyer, Barbara; Pen, Ido; Weissing, Franz J.; Beukeboom, Leo W.

    2008-01-01

    Multiple sex-determining factors have been found in natural populations of the housefly, Musca domestica. Their distribution seems to follow a geographical cline. The 'standard' system, with a male-determining factor, M, located on the Y chromosome, prevails at higher latitudes and altitudes. At low

  10. Determinants of vegetation distribution at continental scale. The contribution of natural and anthropogenic factors

    DEFF Research Database (Denmark)

    Greve, Michelle; Svenning, J.-C.; Lykke, Anne Mette;

    2011-01-01

    It has long been debated what determines distribution of vegetation types, though this has rarely been tested at continental scale. We thus aimed to determine which vegetation types are most accurately predicted by natural environmental factors, and which of these factors best predict current...

  11. Spectrophotometric Determination of Thioridazine Hydrochloride in Tablets and Biological Fluids by Ion-Pair and Oxidation Reactions

    OpenAIRE

    El-Didamony, Akram; Hafeez, Sameh

    2012-01-01

    Two simple, sensitive and selective spectrophotometric methods have been described for the determination of the psychoactive drug, thioridazine HCl in tablets and in biological fluids. The first method is based on the oxidation of thioridazine HCl with measured excess of KMnO4 under acidic conditions followed by the determination of unreacted oxidant using indigo carmine and methyl orange. The second method is based on the formation of ion-pair complexes with the acidic sulphophthalein dyes s...

  12. Determination of Nitric Oxide-Derived Nitrite and Nitrate in Biological Samples by HPLC Coupled to Nitrite Oxidation

    OpenAIRE

    Wu, Anguo; Duan, Tingting; Tang, Dan; Xu, Youhua; Feng, Liang; Zheng, Zhaoguang; Zhu, Jiaxiao; Wang, Rushang; Zhu, Quan

    2013-01-01

    Nitrite and nitrate are main stable products of nitric oxide, a pivotal cellular signaling molecule, in biological fluids. Therefore, accurate measurement of the two ions is profoundly important. Nitrite is difficult to be determined for a larger number of interferences and unstable in the presence of oxygen. In this paper, a simple, cost-effective and accurate HPLC method for the determination of nitrite and nitrate was developed. On the basis of the reaction that nitrite is oxidized rapidly...

  13. Two Methods of Determining Total Phenolic Content of Foods and Juices in a General, Organic, and Biological (GOB) Chemistry Lab

    Science.gov (United States)

    Shaver, Lee Alan; Leung, Sam H.; Puderbaugh, Amy; Angel, Stephen A.

    2011-01-01

    The determination of total phenolics in foods and fruit juices was used successfully as a laboratory experiment in our undergraduate general, organic, and biological (GOB) chemistry course. Two different colorimetric methods were used over three years and comparative student results indicate that a ferrous ammonium sulfate (FAS) indicator…

  14. EXPRESSING HUMAN MATURED BRAIN-DERIVED NEUROTROPHIC FACTOR GENE IN E. Coli AND DETERMINING ITS BIOACTIVITY

    Institute of Scientific and Technical Information of China (English)

    2001-01-01

    Objective Expressing the human matured brain-derived neurotrophic factor (mBDNF) gene in E.Coli and determining its bioactivity. Methods The resulting gene of mBDNF was subcloned into the EcoRI-BamHI site of the expression vector plasmid pBV220. The ligation products were used to transform the competent E. Coli DH5α. The proteins of mBDNF were experessed by temperature inducing. The expression products were dealed with solubilizing inclusion bodies and refolding protein. It was introduced into the embryonic chicken DRG to test whether the expressed mBDNF is a biologically active protein. Results The recombinant plasmid pBV/mBDNF was successfully constructed. By temperature inducing,under the control of the bacteriophage λ PL promoter, the experessed mBDNF protein was a 14Kd non-fusion protein,which existed in E. Coli as inclusion bodies. The size of expressed mBDNF is identical to the prediction. Bioactivity of the products was proved that it could support the cell survival and neurite growth in the primary cultures of embryonic 8-day-old chicken DRG neurons as compared to control.Conclusion The mBDNF gene can be expressed bioactively in E. Coli.

  15. Optimal Endpoint of Therapy in IBD: An Update on Factors Determining a Successful Drug Withdrawal

    Directory of Open Access Journals (Sweden)

    Anita Annaházi

    2015-01-01

    Full Text Available Ulcerative colitis (UC and Crohn’s disease (CD are chronic inflammatory disorders, which require long term treatment to achieve remission and to prevent relapses and cancer. While current therapies are effective in most cases, they can have rare but serious side effects and are often associated with high costs. On the other hand, early discontinuation of an effective treatment may lead to a quick relapse and to complications at the restart of therapy. Therefore it is essential to determine the optimal duration of maintenance therapy, but clear guidelines are missing. The most important questions when deciding whether to continue or withdraw therapy in quiescent UC and CD patients are the efficacy of the continuous treatment to maintain remission in the long term, the frequency and severity of side effects, and the chance of relapse after discontinuation of therapy. This review summarizes the current knowledge on these topics with respect to 5-aminosalicylates, thiopurines, methotrexate, and biological therapies and collects information regarding when and in which specific patient groups, in the absence of risk factors, can withdrawal of therapy be considered without a high risk of relapse. Additionally, the particular aspect of colorectal cancer prevention by current therapies will also be discussed.

  16. Modeling Genetic and Environmental Factors in Biological Systems Using Structural Equation Modeling: An Application to Energy Balance

    OpenAIRE

    Nock, Nora L.; Li, Li; Elston, Robert C.

    2009-01-01

    To improve our understanding of the role(s) that genes and environmental factors play in a complex disease, we need statistical approaches that model multiple factors simultaneously in a hierarchical manner that aims to reflect the underlying biological system(s). We present an approach that models genes as latent constructs, defined by multiple variants (single nucleotide polymorphisms, SNPs) within each gene, using the multivariate statistical framework of structural equation modeling (SEM)...

  17. Profiling healthy eaters: determining factors that predict healthy eating practices among Dutch adults

    NARCIS (Netherlands)

    E. Swan; L. Bouwman; G.J. Hiddink; N. Aarts; M. Koelen

    2015-01-01

    Research has identified multiple factors that predict unhealthy eating practices. However what remains poorly understood are factors that promote healthy eating practices. This study aimed to determine a set of factors that represent a profile of healthy eaters. This research applied Antonovsky's sa

  18. Determination of correction factor ksat for recombination losses in ionization chambers using dual-voltage method

    International Nuclear Information System (INIS)

    A review is presented of determining the saturation correction factor ksat of ionization chambers using a dual-voltage method. Basic relations are listed for the calculation of the correction factor for continuous, pulsed, and pulsed swept radiation, and the methods are presented of solving the relations. The computer code, graphs and tables are listed for determination of the saturation factor on the basis of measurements. The feasibility of the method for practical measurements is discussed. (author). 3 figs., 2 tabs., 10 refs

  19. EFFECTS OF BIOLOGICAL AND SOCIAL-FACTORS ON THE COGNITIVE-DEVELOPMENT OF VERY-LOW-BIRTH-WEIGHT CHILDREN

    NARCIS (Netherlands)

    WEISGLASKUPERUS, N; BAERTS, W; SMRKOVSKY, M; SAUER, PJJ

    1993-01-01

    Objective. To investigate the effects of biological and social factors on the cognitive development of very low birth weight children, a longitudinal follow-up study was conducted from birth to 3.6 years of age. Methodology. The study group consisted of a cohort of 79 surviving high-risk, very low b

  20. Critical-Thinking Grudge Match: Biology vs. Chemistry--Examining Factors That Affect Thinking Skill in Nonmajors Science

    Science.gov (United States)

    Quitadamo, Ian J.; Kurtz, Martha J.; Cornell, Caitlyn Nicole; Griffith, Lindsay; Hancock, Julie; Egbert, Brandi

    2011-01-01

    Chemistry students appear to bring significantly higher critical-thinking skill to their nonmajors course than do biology students. Knowing student preconceptions and thinking ability is essential to learning growth and effective teaching. Of the factors investigated, ethnicity and high school physics had the largest impact on critical-thinking…

  1. Simulating effects of environmental factors on biological control of Tetranychus urticae by Typhlodromus pyri in apple orchards

    NARCIS (Netherlands)

    Hardman, J.M.; Werf, van der W.; Blatt, S.E.; Franklin, J.L.; Karsten, R.; Teismann, H.

    2013-01-01

    Successful biological control of mites is possible under various conditions, and identifying what are the requirements for robust control poses a challenge because interacting factors are involved. Process-based modeling can help to explore these interactions and identify under which conditions biol

  2. Meat science and muscle biology symposium: In utero factors that influence postnatal muscle growth, carcass composition, and meat quality

    Science.gov (United States)

    The Meat Science and Muscle Biology Symposium titled “In utero factors that influence postnatal muscle growth, carcass composition, and meat quality” was held at the Joint Annual Meeting in Phoenix, AZ, July 15 to 19, 2012. The goal of this symposium was to highlight research on the impact of fetal...

  3. A Study of Motivation and Other Factors as Relating to Course Achievement in Introductory College Biology, Chemistry, and Physics.

    Science.gov (United States)

    Pridmore, Brooke M.; Halyard, Rebecca A.

    Results of a preliminary study that examined various factors relating to achievement in introductory level biology, chemistry, and physics classes at a public junior college are presented. Background variables, including age, sex, college major, grade point average, SAT-Verbal and SAT-Quantitative, and the sixteen-part scores of Academic…

  4. Evaluation of the biological differences of canine and human factor VIII in gene delivery: Implications in human hemophilia treatment

    Science.gov (United States)

    The canine is the most important large animal model for testing novel hemophilia A(HA) treatment. It is often necessary to use canine factor VIII (cFIII) gene or protein for the evaluation of HA treatment in the canine model. However, the different biological properties between cFVIII and human FVII...

  5. I love you with all my brain: laying aside the intellectually dull sword of biological determinism

    OpenAIRE

    Woodson, James C.

    2012-01-01

    Background: By organizing and activating our passions with both hormones and experiences, the heart and mind of sexual behavior, sexual motivation, and sexual preference is the brain, the organ of learning. Despite decades of progress, this incontrovertible truth is somehow lost in the far-too-often biologically deterministic interpretation of genetic, hormonal, and anatomical scientific research into the biological origins of sexual motivation. Simplistic and polarized arguments are used in ...

  6. Factors that determine the fees for audit NGOs financial statements in Kosovo

    OpenAIRE

    Bahtijar Berisha; Luan Vardari; Bekim Berisha

    2016-01-01

    The purpose of this paper is to identify, analyze and evaluate the potential factors that influence the determinants of the fee/price of the NGOs financial statements audit in Kosovo based and tested, generally, traditional determinants and known in economic literature on this issue. In our study, we have chosen the NGO sector in Kosovo to investigate the factors that determine the fee/price of their financial statements, because the non-governmental organizations are among the first organiza...

  7. A review of chromatographic methods for the determination of water- and fat-soluble vitamins in biological fluids.

    Science.gov (United States)

    Karaźniewicz-Łada, Marta; Główka, Anna

    2016-01-01

    Vitamins are an essential element of nutrition and thus contribute to human health. Vitamins catalyze many biochemical reactions and their lack or excess can cause health problems. Therefore, monitoring vitamin concentrations in plasma or other biological fluids may be useful in the diagnosis of various disorders as well as in the treatment process. Several chromatographic methods have been developed for the determination of these compounds in biological samples, including high-performance liquid chromatography with UV and fluorescence detection. Recently, high-performance liquid chromatography with tandem mass spectrometry methods have been widely used for the determination of vitamins in complex matrices because of their high sensitivity and selectivity. This method requires preconditioning of samples for analysis, including protein precipitation and/or various extraction techniques. The choice of method may depend on the desired cost, convenience, turnaround time, specificity, and accuracy of the information to be obtained. This article reviews the recently reported chromatographic methods used for determination of vitamins in biological fluids. Relevant papers published mostly during the last 5 years were identified by an extensive PubMed search using appropriate keywords. Particular attention was given to the preparation steps and extraction techniques. This report may be helpful in the selection of procedures that are appropriate for certain types of biological materials and analytes. PMID:26503668

  8. Determination of factor X activator in the venom of the saw-scaled viper (Echis carinatus).

    Science.gov (United States)

    Stocker, K; Fischer, H; Brogli, M

    1986-01-01

    Factor X activator in Echis carinatus venom was determined by incubating the zymogen 'factor X' with venom, interrupting the activation process by ethylenediaminetetraacetic acid and measuring the generated proteinase 'factor Xa' by means of a synthetic chromogenic substrate. A comparison of factor X- and prothrombin-activating potencies in E. carinatus venoms of five different geographic origins revealed no correlation between these two procoagulant activities. PMID:3715901

  9. Novel factors in the pathogenesis of psoriasis and potential drug candidates are found with systems biology approach.

    Directory of Open Access Journals (Sweden)

    Máté Manczinger

    Full Text Available Psoriasis is a multifactorial inflammatory skin disease characterized by increased proliferation of keratinocytes, activation of immune cells and susceptibility to metabolic syndrome. Systems biology approach makes it possible to reveal novel important factors in the pathogenesis of the disease. Protein-protein, protein-DNA, merged (containing both protein-protein and protein-DNA interactions and chemical-protein interaction networks were constructed consisting of differentially expressed genes (DEG between lesional and non-lesional skin samples of psoriatic patients and/or the encoded proteins. DEGs were determined by microarray meta-analysis using MetaOMICS package. We used STRING for protein-protein, CisRED for protein-DNA and STITCH for chemical-protein interaction network construction. General network-, cluster- and motif-analysis were carried out in each network. Many DEG-coded proteins (CCNA2, FYN, PIK3R1, CTGF, F3 and transcription factors (AR, TFDP1, MEF2A, MECOM were identified as central nodes, suggesting their potential role in psoriasis pathogenesis. CCNA2, TFDP1 and MECOM might play role in the hyperproliferation of keratinocytes, whereas FYN may be involved in the disturbed immunity in psoriasis. AR can be an important link between inflammation and insulin resistance, while MEF2A has role in insulin signaling. A controller sub-network was constructed from interlinked positive feedback loops that with the capability to maintain psoriatic lesional phenotype. Analysis of chemical-protein interaction networks detected 34 drugs with previously confirmed disease-modifying effects, 23 drugs with some experimental evidences, and 21 drugs with case reports suggesting their positive or negative effects. In addition, 99 unpublished drug candidates were also found, that might serve future treatments for psoriasis.

  10. Accurate determination of the free-free Gaunt factor. II - relativistic Gaunt factors

    CERN Document Server

    van Hoof, P A M; Williams, R J R; Volk, K; Chatzikos, M; Lykins, M; Porter, R L

    2015-01-01

    When modelling an ionised plasma, all spectral synthesis codes need the thermally averaged free-free Gaunt factor defined over a very wide range of parameter space in order to produce an accurate prediction for the spectrum. Until now no data set exists that would meet these needs completely. We have therefore produced a table of relativistic Gaunt factors over a much wider range of parameter space than has ever been produced before. We present tables of the thermally averaged Gaunt factor covering the range log10(gamma^2) = -6 to 10 and log10(u) = -16 to 13 for all atomic numbers Z = 1 through 36. The data were calculated using the relativistic Bethe-Heitler-Elwert (BHE) approximation and were subsequently merged with accurate non-relativistic results in those parts of the parameter space where the BHE approximation is not valid. These data will be incorporated in the next major release of the spectral synthesis code Cloudy. We also produced tables of the frequency integrated Gaunt factor covering the parame...

  11. Diagnostics in biological rapid sand filters treating groundwater – governing factors for nitrification

    DEFF Research Database (Denmark)

    Albrechtsen, Hans-Jørgen; Gülay, Arda; Smets, Barth F.;

    To improve the insight in the processes in biological rapid sand filters a range of methods were developed to diagnose the microbial mediated processes – particularly nitrification.......To improve the insight in the processes in biological rapid sand filters a range of methods were developed to diagnose the microbial mediated processes – particularly nitrification....

  12. Model-based analysis of the role of biological, hydrological and geochemical factors affecting uranium bioremediation.

    Science.gov (United States)

    Zhao, Jiao; Scheibe, Timothy D; Mahadevan, R

    2011-07-01

    Uranium contamination is a serious concern at several sites motivating the development of novel treatment strategies such as the Geobacter-mediated reductive immobilization of uranium. However, this bioremediation strategy has not yet been optimized for the sustained uranium removal. While several reactive-transport models have been developed to represent Geobacter-mediated bioremediation of uranium, these models often lack the detailed quantitative description of the microbial process (e.g., biomass build-up in both groundwater and sediments, electron transport system, etc.) and the interaction between biogeochemical and hydrological process. In this study, a novel multi-scale model was developed by integrating our recent model on electron capacitance of Geobacter (Zhao et al., 2010) with a comprehensive simulator of coupled fluid flow, hydrologic transport, heat transfer, and biogeochemical reactions. This mechanistic reactive-transport model accurately reproduces the experimental data for the bioremediation of uranium with acetate amendment. We subsequently performed global sensitivity analysis with the reactive-transport model in order to identify the main sources of prediction uncertainty caused by synergistic effects of biological, geochemical, and hydrological processes. The proposed approach successfully captured significant contributing factors across time and space, thereby improving the structure and parameterization of the comprehensive reactive-transport model. The global sensitivity analysis also provides a potentially useful tool to evaluate uranium bioremediation strategy. The simulations suggest that under difficult environments (e.g., highly contaminated with U(VI) at a high migration rate of solutes), the efficiency of uranium removal can be improved by adding Geobacter species to the contaminated site (bioaugmentation) in conjunction with the addition of electron donor (biostimulation). The simulations also highlight the interactive effect of

  13. Model-Based Analysis of the Role of Biological, Hydrological and Geochemical Factors Affecting Uranium Bioremediation

    International Nuclear Information System (INIS)

    Uranium contamination is a serious concern at several sites motivating the development of novel treatment strategies such as the Geobacter-mediated reductive immobilization of uranium. However, this bioremediation strategy has not yet been optimized for the sustained uranium removal. While several reactive-transport models have been developed to represent Geobacter-mediated bioremediation of uranium, these models often lack the detailed quantitative description of the microbial process (e.g., biomass build-up in both groundwater and sediments, electron transport system, etc.) and the interaction between biogeochemical and hydrological process. In this study, a novel multi-scale model was developed by integrating our recent model on electron capacitance of Geobacter (Zhao et al., 2010) with a comprehensive simulator of coupled fluid flow, hydrologic transport, heat transfer, and biogeochemical reactions. This mechanistic reactive-transport model accurately reproduces the experimental data for the bioremediation of uranium with acetate amendment. We subsequently performed global sensitivity analysis with the reactive-transport model in order to identify the main sources of prediction uncertainty caused by synergistic effects of biological, geochemical, and hydrological processes. The proposed approach successfully captured significant contributing factors across time and space, thereby improving the structure and parameterization of the comprehensive reactive-transport model. The global sensitivity analysis also provides a potentially useful tool to evaluate uranium bioremediation strategy. The simulations suggest that under difficult environments (e.g., highly contaminated with U(VI) at a high migration rate of solutes), the efficiency of uranium removal can be improved by adding Geobacter species to the contaminated site (bioaugmentation) in conjunction with the addition of electron donor (biostimulation). The simulations also highlight the interactive effect of

  14. Rapid determination of amino acids in biological samples using a monolithic silica column.

    Science.gov (United States)

    Song, Yanting; Funatsu, Takashi; Tsunoda, Makoto

    2012-05-01

    A high-performance liquid chromatography method in which fluorescence detection is used for the simultaneous determination of 21 amino acids is proposed. Amino acids were derivatized with 4-fluoro-7-nitro-2,1,3-benzoxadiazole (NBD-F) and then separated on a monolithic silica column (MonoClad C18-HS, 150 mm×3 mm i.d.). A mixture of 25 mM citrate buffer containing 25 mM sodium perchlorate (pH 5.5) and acetonitrile was used as the mobile phase. We found that the most significant factor in the separation was temperature, and a linear temperature gradient from 30 to 49°C was used to control the column temperature. The limits of detection and quantification for all amino acids ranged from 3.2 to 57.2 fmol and 10.8 to 191 fmol, respectively. The calibration curves for the NBD-amino acid had good linearity within the range of 40 fmol to 40 pmol when 6-aminocaproic acid was used as an internal standard. Using only conventional instruments, the 21 amino acids could be analyzed within 10 min. This method was found to be suitable for the quantification of the contents of amino acids in mouse plasma and adrenal gland samples.

  15. Spectrophotometric determination of copper(II) in pharmaceutical, biological and water samples by 4-(2'-benzothiazolylazo)-salicylic acid

    Science.gov (United States)

    Hashem, E. Y.; Seleim, M. M.; El-Zohry, A. M.

    2011-09-01

    A highly sensitive method is proposed to determine copper(II) ions by forming a stable complex through their interaction with 4-(2'-benzothiazolylazo)-salicylic acid (BTAS) at room temperature and pH of about 5.0. The complex gave a maximum absorption at λ = 485 nm with a molar absorptivity coefficient of 2.35·104 l/(mol·cm). The linear range for the copper determination is 0.63-5.04 mg/l. The method can be applied to determine copper ions in different biological specimens like some drugs and water samples.

  16. Attitude of teenagers towards biology

    OpenAIRE

    Lavtižar, Teja

    2016-01-01

    ROSE project is a comprehensive study in which students' attitudes towards Science and Technology affected by many factors have been examined. In our study, only some aspects have been focused due to a narrower field of biology which has been interested in, and the direction of the attitude between Biology to elementary school students has been checked. The purpose of the master's work has been to determine the attitude of the teenagers to Biology as science and Biology as a school subjec...

  17. [Bioaccumulation and Biomagnification of Heavy Metals in Three Gorges Reservoir and Effect of Biological Factors].

    Science.gov (United States)

    Wei, Li-li; Zhou, Qiong; Xie, Cong-xin; Wang, Jun; Li, Jun

    2016-01-15

    Three Gorges Reservoir (TGR) reached the maximum water level (175 m) of impoundment in Oct. 2010. In order to reveal the potential influence of the greatest water-level impoundment on the heavy metal pollution in the typical waters of TGR, the content level of trace metals ( Hg, Cd and Pb) in biota and potential biomagnification along the aquatic food chain were investigated in the main stem of TGR from July 2011 to August 2012, as well as the relationship between the trace metal concentrations of aquatic consumers (fish and aquatic invertebrate) and biological factors. Our study showed that no individual data of the three trace metals in biota exceeded the edible safety criteria of aquatic products in China and FAO. In contrast with those before the impoundment of TGR, Hg showed a little higher, while Cd and Pb exhibited a little lower level after the impoundment. Trace metals in TGR exhibited relatively lower concentrations compared with those in reservoirs in other countries. Significant correlations were found between the Cd concentration and body size (body length and body weight) of Cyprinus carpio, as well as the Hg concentration and body size (body length and body weight) of Erythroculter ilishaeformis. As for feeding habits, there was statistically significant difference between trace metal concentrations in herbivorous, planktonic, omnivorous and carnivorous fish. However, no significant difference was found between the metal concentrations in fish with different habitats (pelagic, mesopelagic and benthic). Even so, the overall trend was that fish living in benthic layer had higher heavy metal concentrations than those in pelagic and mesopelagic zones. The regression slopes of log-Hg concentration versus delta(15)N, served as an indicator of trophic magnification factor (TMF). Significant correlations (P < 0.05) were observed for Hg in the food web of TGR. TMF of Hg in TGR indicated lower level (0.046-0.066) in contrast with those in the reservoirs of

  18. The role of Ikaros transcriptional factor in normal hematopoiesis and leukemogenesis: biological and clinical aspects

    Directory of Open Access Journals (Sweden)

    V. S. Vshivkoo

    2015-01-01

    Full Text Available Investigation of the pathogenesis and factors effecting recurrence, progression and drug resistance in acute leukemia (AL remains a major challenge for hematology and other related areas. The role of more than 50 genes and proteins in the AL pathogenesis has been shown, including the well-studied tumor suppressor (CDKN2A/CDKN2B, RB1, PTEN, p53, and classical fusion genes (BCR/ABL1, TEL/AML1, E2A/PBX, MLL translocations. In addition, high frequency of aberrations in genes responsible for lymphoid differentiation have been identified such as transcription factors (PAX5, IKZF1 and EBF1, transcriptional regulation of the genes (ETV6, ERG, and signaling pathways of antigen receptors (BTLA, CD200, TOX, BLNK, VPREB1, as well as genes involved in chemoresistance of leukemia cells (NR3C1. In recent studies, Ikaros abnormalities have been reported to be frequently associated with AL. Ikaros is a member of a Kruppel-like family of zinc finger transcription factors that also includes IKZF2 (Helios, IKZF3 (Aiolos, Eos and Pegasus, and encoded by the IKZF1 gene. In hematopoietic cells Ikaros functions as a transcription factor, a key protein controlling T-, B-, NK-, and dendritic cells early differentiation. At the early hematopoiesis stages, it represses the myeloid and erythroid lineages, and stimulates the lymphoid differentiation. Ikaros also normally modulates immune response and plays role of a tumor suppressor in lymphoid malignances. Data from numerous clinical studies confirmed an association between the presence of IKZF1 aberrations and B-cell and, to a lesser extent, T-cell acute lymphoblastic leukemia (ALL development. Besides, loss of Ikaros function was associated with progression of myeloproliferative diseases to acute myeloid leukemia (AML in children. From clinical point of view, particular intragenic IKZF1 deletions and a short (non-functional protein Ikaros isoforms, which may occur as a result of intragenic deletions or aberrant splicing

  19. Healthy Chilean Adolescents with HOMA-IR ≥ 2.6 Have Increased Cardiometabolic Risk: Association with Genetic, Biological, and Environmental Factors

    Directory of Open Access Journals (Sweden)

    R. Burrows

    2015-01-01

    Full Text Available Objective. To determine the optimal cutoff of the homeostasis model assessment-insulin resistance (HOMA-IR for diagnosis of the metabolic syndrome (MetS in adolescents and examine whether insulin resistance (IR, determined by this method, was related to genetic, biological, and environmental factors. Methods. In 667 adolescents (16.8 ± 0.3 y, BMI, waist circumference, glucose, insulin, adiponectin, diet, and physical activity were measured. Fat and fat-free mass were assessed by dual-energy X-ray absorptiometry. Family history of type 2 diabetes (FHDM was reported. We determined the optimal cutoff of HOMA-IR to diagnose MetS (IDF criteria using ROC analysis. IR was defined as HOMA-IR values above the cutoff. We tested the influence of genetic, biological, and environmental factors on IR using logistic regression analyses. Results. Of the participants, 16% were obese and 9.4 % met criteria for MetS. The optimal cutoff for MetS diagnosis was a HOMA-IR value of 2.6. Based on this value, 16.3% of participants had IR. Adolescents with IR had a significantly higher prevalence of obesity, abdominal obesity, fasting hyperglycemia, and MetS compared to those who were not IR. FHDM, sarcopenia, obesity, and low adiponectin significantly increased the risk of IR. Conclusions. In adolescents, HOMA-IR ≥ 2.6 was associated with greater cardiometabolic risk.

  20. Java project on periodontal diseases. The natural development of periodontitis: risk factors, risk predictors and risk determinants : risk factors, risk predictors and risk determinants

    NARCIS (Netherlands)

    Van der Velden, U.; Abbas, F.; Armand, S.; Loos, B. G.; Timmerman, M. F.; Van der Weijden, G. A.; Van Winkelhoff, A. J.; Winkel, E. G.

    2006-01-01

    Objective: To identify risk factors, risk predictors and risk determinants for onset and progression of periodontitis. Material and Methods: For this longitudinal, prospective study all subjects in the age range 15-25 years living in a village of approximately 2000 inhabitants at a tea estate on Wes

  1. Variability of Biological Degradation of Aromatic Hydrocarbons in an Aerobic Aquifer Determined by Laboratory Batch Experiments

    DEFF Research Database (Denmark)

    Nielsen, Per Henning; Christensen, Thomas Højlund

    1994-01-01

    The biological aerobic degradation of 7 aromatic hydrocarbons (benzene, toluene, o-xylene, p-dichlorobenzene, o-dichlorobenzene, naphthalene and biphenyl) was studied for 149 days in replicate laboratory batch experiments with groundwater and sediment from 8 localities representing a 15 m × 30 m...... section of an aerobic aquifer. Compared to biologically deactivated control experiments all compounds were biologically degraded. Degradation curves were very reproducible for some compounds (benzene, toluene, o-xylene, o-dichlorobenzene and p-dichlorobenzene) and less reproducible for other (naphthalene...... and biphenyl). Based on observed length of lag phases, length of the degradation periods and percent degradation, the variation among the 8 localities appears to be modest. However, detailed examination of the degradation rates revealed statistically significant variation among localities for benzene, toluene...

  2. Enhancing China’s Energy Security: Determining Influential Factors and Effective Strategic Measures

    DEFF Research Database (Denmark)

    Ren, Jingzheng; Sovacool, Benjamin

    2014-01-01

    This study investigates the most influential factors affecting China’s energy security. It also identifies the most effective strategic measures for enhancing it. Fuzzy AHP has been used to determine weights for ranking the importance of Chinese energy security factors, and it has also been used...... to determine the priorities of the strategic measures with respect to enhancing those same factors. The study argues that a low proportion of renewable energy penetration is the most severe factor threatening China’s energy security, and that conducting research and development on energy technologies...... and improving energy efficiency is the most salient, positive, and necessary strategic measure....

  3. Use of novel silver nanoparticles with Hyaluronan as potential biological labels for determining the quality of embryos development

    Science.gov (United States)

    Syrvatka, Vasyl J.; Slyvchuk, Yurij I.; Rozgoni, Ivan I.; Hevkan, Ivan I.; Bilyi, Oleksandr I.; Osypchuk, Oleksandr S.; Zyuzyun, Aza B.

    2013-09-01

    In reproductive medicine it is important to determine the quality of embryo development without interference in their function and viability. The surface plasmon resonance of silver nanoparticles makes them promising candidates for optical sensing, molecular labeling and imaging applications. Furthermore unique optical properties of silver nanoparticles provide an opportunity to use them as real time analytic tools in living state especially for observation of dynamic processes in gametes and embryos. The main aim of the study was to investigate the physicochemical properties and biological activities of novel silver nanoparticles with prospect of their use for the determining the quality of embryo development. For this purpose, we investigated the optical properties of new silver nanoparticles in biological mediums during cultivation and their influence on rabbit's embryos development in vitro. The physicochemical and biological properties of novel silver nanoparticles were compared with silver nanoparticles identical in size and shapes but with different chemical surfaces modifications by polyvinylpyrrolidone and bovine serum albumin. The results suggest that silver nanoparticles with hyaluronic acid were disintegrated with the formation of new complexes with proteins in biological mediums. This property with strong optical surface plasmon resonance of novel silver nanoparticles with hyaluronan makes them promising candidates in diagnostic area and gives reasons to explore them as biomarkers of target molecules. Nevertheless novel silver nanoparticles with hyaluronan at the concentrations of 0.1-1 μg/ml have no toxic effect on rabbit's embryos development and can be successfully applied in reproductive medicine.

  4. Elements determination of clinical relevance in biological tissues Dmdmdx/J dystrophic mice strains investigated by NAA

    International Nuclear Information System (INIS)

    In this work the determination of chemistry elements in biological tissues (whole blood, bones and organs) of dystrophic mice, used as animal model of Duchenne Muscular Dystrophy (DMD), was performed using analytical nuclear technique. The aim of this work was to determine reference values of elements of clinical (Ca, Cl, K, Mg, Na) and nutritional (Br and S) relevance in whole blood, tibia, quadriceps and hearts from Dmdmdx/J (10 males and 10 females) dystrophic mice and C57BL/6J (10 males) control group mice, using Neutron Activation Analysis technique (NAA). To show in more details the alterations that this disease may cause in these biological tissues, correlations matrixes of the DMDmdx/J mouse strain were generated and compared with C57BL/6J control group. For this study 119 samples of biological tissue were irradiated in the IEA-R1 nuclear reactor at IPEN (Sao Paulo, Brazil). The concentrations of these elements in biological tissues of Dmdmdx/J and C57B/6J mice are the first indicative interval for reference values. Moreover, the alteration in some correlation coefficients data among the elements in the health status and in the diseased status indicates a connection between these elements in whole blood, tibia, quadriceps and heart. These results may help the researchers to evaluate the efficiency of new treatments and to compare the advantages of different treatment approaches before performing tests in patients with muscular dystrophy. (author)

  5. Determining the impacts of trawling on benthic function in European waters : a biological traits approach

    DEFF Research Database (Denmark)

    Bolam, Stefan; Kenny, Andrew; Garcia, Clement;

    on benthic ecosystem functioning over much larger spatial scales than previously undertaken. Biological traits information from 887 stations across European waters (Norwegian, UK, Belgian, Dutch, Danish waters, the Mediterranean and Black Sea) were analysed to: i) quantify the relationships between infaunal...

  6. Incorporating Biological Mass Spectrometry into Undergraduate Teaching Labs, Part 2: Peptide Identification via Molecular Mass Determination

    Science.gov (United States)

    Arnquist, Isaac J.; Beussman, Douglas J.

    2009-01-01

    Mass spectrometry has become a routine analytical tool in the undergraduate curriculum in the form of GC-MS. While relatively few undergraduate programs have incorporated biological mass spectrometry into their programs, the importance of these techniques, as demonstrated by their recognition with the 2002 Nobel Prize, will hopefully lead to…

  7. Moooving forward on determining biologically active compounds in milk and their impact on health

    Science.gov (United States)

    Recent studies have demonstrated that some of the lesser studied components in milk, known as biologically active compounds (BACs), may provide potential benefits to human health. The added health-value of raw milk and milk from organic and grass-fed herds is strongly debated because of limited, an...

  8. Determination of the Biologically Relevant Sampling Depth for Terrestrial and Aquatic Ecological Risk Assessments (Final Report)

    Science.gov (United States)

    This technical paper provides defensible approximations for what the depth of the biologically active zone, or “biotic zone” is within certain environments. The methods used in this study differ somewhat between Part 1 (Terrestrial Biotic Zone) and Part 2 (Aquatic Biotic Zone). ...

  9. Modular and cultural factors in biological understanding: an experimental approach to the cognitive basis of science

    OpenAIRE

    Atran, Scott

    2002-01-01

    What follows is a discussion of three sets of experimental results that deal with various aspects of universal biological understanding among American and Maya children and adults. The first set of experiments shows that by the age of four-to-five years (the earliest age tested in this regard) urban American and Yukatek Maya children employ a concept of innate species potential, or underlying essence, as an inferential framework for understanding the affiliation of an organism to a biological...

  10. Determination of thorium and uranium in biological samples by inductively coupled plasma mass spectrometry using internal standardisation

    International Nuclear Information System (INIS)

    The Th and U contents of six typical biological samples (for example US NIST SRMs and Japan NIES CRMs) were determined by inductively coupled plasma mass spectrometry (ICP-MS). The internal standardisation method was adopted to compensate for non-spectroscopic interferences arising from matrix elements in the sample solution. Bismuth and Tl were chosen as the internal standards, and the effect of the matrix on the behaviour of their signals was monitored by adding several elements to the NIST human lung sample. It would appear that elements of similar mass give similar signal responses, thus In is unsuitable as the internal standard in this instance. After correction by either Bi or Tl internal standardisation, the results for the Th and U concentrations agreed well with literature values, showing that both are applicable for the determination of Th and U in biological samples. (author)

  11. DETERMINATION OF RATIONAL KINEMATIC DISCREPANCY FACTOR AND DIAGRAMS OF WHEEL TRACTOR DRIVE AXLE GEAR

    OpenAIRE

    A. V. Gouskov

    2008-01-01

    Accepting a traction efficiency as a criterion of effectiveness an optimum kinematic discrepancy factor  for a 4К4-model tractor with identical or different wheels and also schemes of drive axle gears are determined in the paper.

  12. Adult Learning Open University Determinants (ALOUD) study: Psychological factors associated with study success

    NARCIS (Netherlands)

    Neroni, Joyce; De Groot, Renate; Kirschner, Paul A.

    2013-01-01

    Neroni, J., De Groot, R. H. M., & Kirschner, P. A. (2012, 7 November). Adult Learning Open University Determinants (ALOUD) study: Psychological factors associated with study success. Poster presentation at the International ICO Fall School, Girona, Spain.

  13. Discussion on wind factor influencing the distribution of biological soil crusts on surface of sand dunes

    Institute of Scientific and Technical Information of China (English)

    YongSheng Wu; Hasi Erdun; RuiPing Yin; Xin Zhang; Jie Ren; Jian Wang; XiuMin Tian; ZeKun Li; HengLu Miao

    2013-01-01

    Biological soil crusts are widely distributed in arid and semi-arid regions, whose formation and development have an important impact on the restoration process of the desert ecosystem. In order to explore the relationship between surface airflow and development characteristics of biological soil crusts, we studied surface airflow pattern and development characteristics of biological soil crusts on the fixed dune profile through field observation. Results indicate that the speed of near-surface airflow is the lowest at the foot of windward slope and the highest at the crest, showing an increasing trend from the foot to the crest. At the leeward side, although near-surface airflow increases slightly at the lower part of the slope after an initial sudden decrease at upper part of the slope, its overall trend decreases from the crest. Wind velocity variation coefficient varied at different heights over each observation site. The thickness, shear strength of biological soil crusts and percentage of fine particles at crusts layer decreased from the slope foot to the upper part, showing that biological soil crusts are less developed in high wind speed areas and well developed in low wind speed areas. It can be seen that there is a close relationship between the distribution of biological soil crusts in different parts of the dunes and changes in airflow due to geomorphologic variation.

  14. Dithizone chloroform single drop microextraction system combined with electrothermal atomic absorption spectrometry using Ir as permanent modifier for the determination of Cd in water and biological samples

    Science.gov (United States)

    Fan, Zhefeng; Zhou, Wei

    2006-07-01

    A simple and sensitive method using dithizone-chloroform single drop microextraction has been developed for separation and preconcentration of trace Cd prior to its determination by electrothermal atomic absorption spectrometry with Ir as permanent modifier. Parameters, such as pyrolysis and atomization temperature, solvent type, pH, dithizone concentration, extraction time, organic drop volume, stirring rate and sample volume were investigated. Under the optimized conditions, a detection limit (3 σ) of 0.7 ng/l and enrichment factor of 65 were achieved. The relative standard deviation was 7.4% ( c = 0.2 μg/l, n = 5). The developed method has been applied to the determination of trace Cd in water samples and biological reference materials with satisfactory results.

  15. Dithizone-chloroform single drop microextraction system combined with electrothermal atomic absorption spectrometry using Ir as permanent modifier for the determination of Cd in water and biological samples

    Energy Technology Data Exchange (ETDEWEB)

    Fan Zhefeng [Department of Chemistry, Shanxi Normal University, Linfen 041004 (China)]. E-mail: zhefengfan@163.com; Zhou Wei [Department of Chemistry, Shanxi Normal University, Linfen 041004 (China)

    2006-07-15

    A simple and sensitive method using dithizone-chloroform single drop microextraction has been developed for separation and preconcentration of trace Cd prior to its determination by electrothermal atomic absorption spectrometry with Ir as permanent modifier. Parameters, such as pyrolysis and atomization temperature, solvent type, pH, dithizone concentration, extraction time, organic drop volume, stirring rate and sample volume were investigated. Under the optimized conditions, a detection limit (3{sigma}) of 0.7 ng/l and enrichment factor of 65 were achieved. The relative standard deviation was 7.4% (c = 0.2 {mu}g/l, n = 5). The developed method has been applied to the determination of trace Cd in water samples and biological reference materials with satisfactory results.

  16. Report on intercomparison run SNR-1 for the determination of trace elements in synthetic resin simulating biological material

    International Nuclear Information System (INIS)

    A synthetic resin, SNR-1, simulating biological material and containing homogeneously distributed trace amounts of As, Au, Br, Cr, Cs, Hg, La, Mn, Rb, Sb, Se and Sr, was made available to 16 laboratories in the form of 50 mg - pellets. Various methods for the quantitative determination of these elements (and, in some cases, also of impurities) including neutron activation analysis, and neutron activation analysis with radio-chemical analysis were used in an interlaboratory comparative study. The results are tabulated

  17. Determination of selenium in biological materials by flow injection hydride generation atomic absorption spectrometry (FI-HG-AAS)

    OpenAIRE

    Galgan, Vera

    2007-01-01

    The selenium (Se) poor environment in the Scandinavian countries focused the interest on the development of an analytical method with high capacity, sensitivity, low limit of detection, including automated wet digestion, automated analysis and computer aided calculation. To facilitate the choice of an appropriate analytical method, procedures for determination in biological materials were discussed. The most frequently used sample-preparation procedures and various analytical techniques were ...

  18. Expression of vascular endothelial growth factor in cultured human dental follicle cells and its biological roles

    Institute of Scientific and Technical Information of China (English)

    Xue-peng CHEN; Hong QIAN; Jun-jie WU; Xian-wei MA; Ze-xu GU; Hai-yan SUN; Yin-zhong DUAN; Zuo-lin JIN

    2007-01-01

    Aim: To investigate the expression of vascular endothelial growth factor (VEGF) in cultured human dental follicle cells (HDFC), and to examine the roles of VEGF in the proliferation, differentiation, and apoptosis of HDFC in vitro. Methods: Immunocytochemistry, ELISA, and RT-PCR were used to detect the expression and transcription of VEGF in cultured HDFC. The dose-dependent and the time-course effect of VEGF on cell proliferation and alkaline phosphatase (ALP) activ-ity in cultured HDFC were determined by MTT assay and colorimetric ALP assay, respectively. The effect of specific mitogen-activated protein kinase (MAPK) inhibitors (PD98059 and U0126) on the VEGF-mediated HDFC proliferation was also determined by MTT assay. The effect of VEGF on HDFC apoptosis was measured by flow cytometry. Results: VEGF was transcribed and expressed in cultured HDFC. VEGF at 10-300 μg/L significantly increased HDFC proliferation and ALP activity compared to the control. Following 1, 3, 5, or 7 d of stimulation, VEGF induced a significant increase in HDFC proliferation compared with the corresponding control, while VEGF was effective at increasing ALP activity at the incubation time point of 3, 5, or 7 d. PD98059 and U0126 could attenuate the VEGF-mediated HDFC proliferation. Fewer apoptotic cells were observed in the VEGF-treated groups compared to the controls, although the difference was not statistically significant. Conclusion: VEGF is expressed in cultured HDFC, and at a proper concentration range can stimulate HDFC proliferation, induce HDFC to differentiate in a "cementoblast/osteoblast" pathway and protect HDFC from apoptosis. The MAPK signaling pathway might be involved in the VEGF-medi-ated HDFC proliferation.

  19. Analysis of factors that determine human's health and influence on it

    OpenAIRE

    Muntyan V.S.

    2010-01-01

    Basic factors, which straightly or indirectly influence on a human's health and stipulating accents on the healthy way of life are exposed. Positive influence on strengthening human's health by increasing the dose of physical activity / loadings, application of facilities of physical culture and sport is grounded. It is stressed that the human's health must be examined in a high-quality aspect, as dialectical unity of biological, social and spiritual. Special role is given to human's adaptati...

  20. What are the most important factors determining different vegetation types in the Chapada Diamantina, Brazil?

    Science.gov (United States)

    Neves, S P S; Funch, R; Conceição, A A; Miranda, L A P; Funch, L S

    2016-06-01

    A transect was used to examine the environmental and biological descriptors of a compact vegetation mosaic in the Chapada Diamantina in northeastern Brazil, including the floristic composition, spectrum of plant life forms, rainfall, and soil properties that defined areas of cerrado (Brazilian savanna), caatinga (seasonally dry tropical forest thorny, deciduous shrub/arboreal vegetation) and cerrado-caatinga transition vegetation. The floristic survey was made monthly from April/2009 to March/2012. A dendrogram of similarity was generated using the Jaccard Index based on a matrix of the species that occurred in at least two of the vegetation types examined. The proportions of life forms in each vegetation type were compared using the chi-square test. Composite soil samples were analyzed by simple variance (ANOVA) to examine relationships between soil parameters of each vegetation type and the transition area. The monthly precipitation levels in each vegetation type were measured and compared using the chi-square test. A total of 323 species of angiosperms were collected distributed in 193 genera and 54 families. The dendrogram demonstrated strong difference between the floristic compositions of the cerrado and caatinga, sharing 2% similarity. The chi-square test did not demonstrate any significant statistical differences between the monthly values of recorded rainfall. The organic matter and clay contents of the soilsin the caatinga increased while sand decreased, and the proportions of therophyte, hemicryptophyte, and chamaephyte life forms decreased and phanerophytes increased. We can therefore conclude that the floristic composition and the spectrum of life forms combined to define the cerrado and caatinga vegetation along the transect examined, with soil being the principal conditioning factor determining the different vegetation types, independent of precipitation levels. PMID:26934155

  1. GC-MS and LC-MS approaches for determination of tocopherols and tocotrienols in biological and food matrices.

    Science.gov (United States)

    Bartosińska, E; Buszewska-Forajta, M; Siluk, D

    2016-08-01

    Tocopherols and tocotrienols, widely described as vitamin E derivatives, have been proven to take part in a number of important biological functions. Among them, antioxidant properties had been investigated and documented in the literature. Since tocochromanols have revealed their plausible beneficial impact on several pathological processes, such as cancerogenesis or cognitive impairment diseases, there is a growing interest in quantitative determination of these compounds in biological fluids, tissues and plant organs. However, due to vitamin E chemical features, such as lipophilic and non-polar characteristics, quantitative determination of the compounds seems to be problematic. In this paper we present current analytical approaches in tocopherols and tocotrienols determination in biological and food matrices with the use of chromatographic techniques, especially gas chromatography (GC) and high performance liquid chromatography (HPLC) coupled with mass spectrometry. Derivatization techniques applied for GC-MS analysis in the case of tocol derivatives, especially silylation and acylation, are described. Significant attention is paid to ionization process of tocopherols and tocotrienols. PMID:26964480

  2. Analysis of factors that determine human's health and influence on it

    Directory of Open Access Journals (Sweden)

    Muntyan V.S.

    2010-12-01

    Full Text Available Basic factors, which straightly or indirectly influence on a human's health and stipulating accents on the healthy way of life are exposed. Positive influence on strengthening human's health by increasing the dose of physical activity / loadings, application of facilities of physical culture and sport is grounded. It is stressed that the human's health must be examined in a high-quality aspect, as dialectical unity of biological, social and spiritual. Special role is given to human's adaptation and most widespread factors, that negatively influence on its health.

  3. Using Exploratory Factor Analysis to Determine the Dimensionality of Discrete Responses

    NARCIS (Netherlands)

    Barendse, Mariska; Oort, Frans J.; Timmerman, Marieke

    2015-01-01

    Exploratory factor analysis (EFA) is commonly used to determine the dimensionality of continuous data. In a simulation study we investigate its usefulness with discrete data. We vary response scales (continuous, dichotomous, polytomous), factor loadings (medium, high), sample size (small, large), an

  4. Using exploratory factor analysis to determine the dimensionality of discrete responses

    NARCIS (Netherlands)

    M.T. Barendse; F.J. Oort; M.E Timmerman

    2014-01-01

    Exploratory factor analysis (EFA) is commonly used to determine the dimensionality of continuous data. In a simulation study we investigate its usefulness with discrete data. We vary response scales (continuous, dichotomous, polytomous), factor loadings (medium, high), sample size (small, large), an

  5. The New Factors Determining on Attract Foreign Direct Investment in the Sports Industry of Iran

    Directory of Open Access Journals (Sweden)

    Mahdiyeh Rooham

    2014-09-01

    Full Text Available The aim of this study was to investigate factors determining, including: economic, support, encouragement, political and diplomatic on attract foreign direct investment in the sport industry of Iran. Current study was an applied research in terms aims, and descriptive - analytical in terms methods of data collection, which was conducted as fieldwork. The statistical population was all board members of the 12 federations and 3 investment companies in the sports industry of Iran (N≈127. 100 subjects were determined based on Cohen's tables and questionnaires were distributed among them. Research’ measuring tool was questionnaire including 30 questions by researcher made. The questionnaire provided during a preliminary study by using Delphi method, which the reliability of the questionnaire was determined using the method Cronbach's alpha statistic 92%. After collecting the questionnaires, it was found that the data have not normally distributed by using Kolmogorov–Smirnov test. Thus Kruskal-Wallis and Friedman tests and factor analysis with SPSS software were used for determine the contribution of each factor on attract foreign direct investment. The results showed that the privatization factor in the country's sports industry among the economic factors, the factor of government support of investor in sports among the support and encouragement factors, and trying to remove economic sanctions against Iran among the political factors had the greatest impact on attracting foreign direct investment on sports industry of Iran.

  6. FACTORS DETERMINING CUSTOMERS’ ADOPTION OF INTERNET BANKING : A Quantitative Study of Swedish Customers

    OpenAIRE

    Qayyum, Faisal; Ali, Haider

    2012-01-01

    Title: Factors determining customers’ adoption of internet bankingResearch Question: Which factors are important for Swedish customers in the adoption of internet banking? Purpose: The purpose of this study is to identify and analyze the most important factors that can influence the adoption of internet banking by Swedish customers. We focus on the adoption of internet banking by taking into account customer point of view. Methodology: This study employs qualitative as well as quantitative re...

  7. Determination of Strong Acidic Drugs in Biological Matrices: A Review of Separation Methods

    Directory of Open Access Journals (Sweden)

    Lingli Mu

    2014-01-01

    Full Text Available Strong acidic drugs are a class of chemical compounds that normally have high hydrophilicity and large negative charges, such as organophosphatic compounds and organosulphonic compounds. This review focuses on sample preparation and separation methods for this group of compounds in biological matrices in recent years. A wide range of separation techniques, especially chromatographic method, are presented and critically discussed, which include liquid chromatography (e.g., ion-pair and ion-exchange chromatography, capillary electrophoresis (CE, and other types. Due to the extremely low concentration level of target analytes as well as the complexity of biological matrices, sample pretreatment methods, such as dilute and shoot methods, protein precipitation (PP, liquid-liquid extraction (LLE, solid-phase extraction (SPE, degradation, and derivatization strategy, also play important roles for the development of successful analytical methods and thus are also discussed.

  8. Electroanalytical Determination of Danofloxacin in Biological Samples Using Square Wave Voltammetry

    Directory of Open Access Journals (Sweden)

    Chirley Vanessa Boone

    2014-10-01

    Full Text Available The voltammetric behavior of danofloxacin (DFX has been studied, in aqueous solution, on a glassy carbon electrode using square wave voltammetry (SWV as electroanalytical technique. After optimization of the experimental conditions, DFX was analyzed in spiked biologic samples using a Britton-Robinson buffer with pH = 5.0 as the supporting electrolyte. Oxidation occurs at 0.98 V vs. Ag/AgCl in a two-electron process controlled by adsorption of the electrogenerated products on the electrode surface. A acceptable recovery was obtained for assay of spiked biologic samples, with value of 98.7% for the swine urine and 95.3 % for the bovine urine.

  9. Respiratory function and other biological risk factors for completed suicide: 40 years of follow-up of European cohorts of the Seven Countries Study

    NARCIS (Netherlands)

    Giltay, E.J.; Zitman, F.G.; Menotti, A.; Nissinen, A.; Jacobs, D.R.; Adachi, H.; Kafatos, A.; Kromhout, D.

    2010-01-01

    Background - Prospective cohort studies on biological risk factors of completed suicide are scarce. We aimed to test which biological risk factors independently identify subjects at increased risk of suicidal death. Methods - In the prospective cohort of the Seven Countries Study, 5,321 middle-aged

  10. Reproductive biology and age determination of Garra rufa Heckel, 1843 (Actinopterygii: Cyprinidae) in central Iran

    OpenAIRE

    ABEDI, Masoud; SHIVA, Amir Houshang; Mohammadi, Hamid; MALEKPOUR, Rokhsareh

    2011-01-01

    Some aspects of the reproductive biology of Garra rufa Heckel, 1843, a native cyprinid fish species from the Armand stream in Chaharmahal-o-Bakhtiari province, central Iran, were investigated by regular monthly collections throughout 1 year. A significant relationship between length and weight and the isometric growth pattern were observed in this fish. There were no significant differences in the total number of male and female specimens. The population of this cyprinid fish had a narrow age...

  11. Biological psychological and social determinants of old age: bio-psycho-social aspects of human aging.

    Science.gov (United States)

    Dziechciaż, Małgorzata; Filip, Rafał

    2014-01-01

    The aging of humans is a physiological and dynamic process ongoing with time. In accordance with most gerontologists' assertions it starts in the fourth decade of life and leads to death. The process of human aging is complex and individualized, occurs in the biological, psychological and social sphere. Biological aging is characterized by progressive age-changes in metabolism and physicochemical properties of cells, leading to impaired self-regulation, regeneration, and to structural changes and functional tissues and organs. It is a natural and irreversible process which can run as successful aging, typical or pathological. Biological changes that occur with age in the human body affect mood, attitude to the environment, physical condition and social activity, and designate the place of seniors in the family and society. Psychical ageing refers to human awareness and his adaptability to the ageing process. Among adaptation attitudes we can differentiate: constructive, dependence, hostile towards others and towards self attitudes. With progressed age, difficulties with adjustment to the new situation are increasing, adverse changes in the cognitive and intellectual sphere take place, perception process involutes, perceived sensations and information received is lowered, and thinking processes change. Social ageing is limited to the role of an old person is culturally conditioned and may change as customs change. Social ageing refers to how a human being perceives the ageing process and how society sees it. PMID:25528930

  12. Biological monitoring to determine worker dose in a butadiene processing plant

    Energy Technology Data Exchange (ETDEWEB)

    Bechtold, W.E.; Hayes, R.B. [National Cancer Inst., Bethesda, MD (United States)

    1995-12-01

    Butadiene (BD) is a reactive gas used extensively in the rubber industry and is also found in combustion products. Although BD is genotoxic and acts as an animal carcinogen, the evidence for carcinogenicity in humans is limited. Extrapolation from animal studies on BD carcinogenicity to risk in humans has been controversial because of uncertainties regarding relative biologic exposure and related effects in humans vs. experimental animals. To reduce this uncertainty, a study was designed to characterize exposure to BD at a polymer production facility and to relate this exposure to mutational and cytogenetic effects. Biological monitoring was used to better assess the internal dose of BD received by the workers. Measurement of 1,2-dihydroxy-4-(N-acetylcysteinyl) butane (M1) in urine served as the biomarker in this study. M1 has been shown to correlate with area monitoring in previous studies. Most studies that relate exposure to a toxic chemical with its biological effects rely on exposure concentration as the dose metric; however, exposure concentration may or may not reflect the actual internal dose of the chemical.

  13. Two-dimensional flow nanometry of biological nanoparticles for accurate determination of their size and emission intensity

    Science.gov (United States)

    Block, Stephan; Fast, Björn Johansson; Lundgren, Anders; Zhdanov, Vladimir P.; Höök, Fredrik

    2016-01-01

    Biological nanoparticles (BNPs) are of high interest due to their key role in various biological processes and use as biomarkers. BNP size and composition are decisive for their functions, but simultaneous determination of both properties with high accuracy remains challenging. Optical microscopy allows precise determination of fluorescence/scattering intensity, but not the size of individual BNPs. The latter is better determined by tracking their random motion in bulk, but the limited illumination volume for tracking this motion impedes reliable intensity determination. Here, we show that by attaching BNPs to a supported lipid bilayer, subjecting them to hydrodynamic flows and tracking their motion via surface-sensitive optical imaging enable determination of their diffusion coefficients and flow-induced drifts, from which accurate quantification of both BNP size and emission intensity can be made. For vesicles, the accuracy of this approach is demonstrated by resolving the expected radius-squared dependence of their fluorescence intensity for radii down to 15 nm. PMID:27658367

  14. Determining eyeball surface area directly exposed to the effects of external factors.

    Science.gov (United States)

    Juliszewski, Tadeusz; Kadłuczka, Filip; Kiełbasa, Paweł

    2016-01-01

    This article discusses determining the surface area of eyeballs of men and women exposed to the direct effects of external factors in the working environment. For one eye, the mean surface is 172-182 mm(2). The determined surface area can be used in formulas for calculating the exposure of eyeballs to harmful chemical substances in workplace air. PMID:26758027

  15. 24 CFR 30.80 - Factors in determining amount of civil money penalty.

    Science.gov (United States)

    2010-04-01

    ... civil money penalty. 30.80 Section 30.80 Housing and Urban Development Office of the Secretary, Department of Housing and Urban Development CIVIL MONEY PENALTIES: CERTAIN PROHIBITED CONDUCT Procedures § 30.80 Factors in determining amount of civil money penalty. After determining that a respondent...

  16. High resolution spectroscopy for Cepheids distance determination. II. A period- projection factor relation

    CERN Document Server

    Nardetto, N; Mathias, Ph; Fokin, A; Gillet, D

    2008-01-01

    The projection factor is a key quantity for the interferometric Baade-Wesselink (hereafter IBW) and surface-brightness (hereafter SB) methods of determining the distance of Cepheids. Indeed, it allows a consistent combination of angular and linear diameters of the star. We aim to determine consistent projection factors that include the dynamical structure of the Cepheids' atmosphere. Methods. Hydrodynamical models of delta Cep and l Car have been used to validate a spectroscopic method of determining the projection factor. This method, based on the amplitude of the radial velocity curve, is applied to eight stars observed with the HARPS spectrometer. The projection factor is divided into three sub-concepts : (1) a geometrical effect, (2) the velocity gradient within the atmosphere, and (3) the relative motion of the "optical" pulsating photosphere compared to the corresponding mass elements (hereafter fo-g). Both, (1) and (3) are deduced from geometrical and hydrodynamical models, respectively, while (2) is d...

  17. Some biological factors related to the 137Cs concentration of marine organisms

    International Nuclear Information System (INIS)

    Marine Ecology Research Institute has been studying the factors controlling the concentration of radionuclides in marine biota. Weight of fish seemed to be an important factor controlling the concentration of 137Cs because of the good correlation observed between the weight and the concentration of 137Cs. Food habits also seemed to be an important factor because fishes in higher trophic levels tended to indicate higher concentration factors and a positive correlation was observed between the concentrations of predator fishes and those of the foodstuff. Gender could be another factor controlling the concentration of 137Cs because the difference of 137Cs between gender was observed in rockfish and marbled sole. (author)

  18. Determination of recovery factor for simulation of non-equilibrium sedimentation in reservoir

    Institute of Scientific and Technical Information of China (English)

    Jungkyu AHN; ChihTed YANG

    2015-01-01

    It is generally acceptable to assume that bed material load is equal to sediment transport capacity, if the exchange between bed and flow occurs instantaneously. However, for non-equilibrium sediment transport process, there are spatial and temporal delay effects. This is especially true for reservoir sedimentation processes. Recovery factor is a coefficient for non-equilibrium sediment transport. The determination of recovery factor can be obtained either experimentally or numerically. There is no consensus on the value of recovery factor in previous literatures. Numerical simulations with a semi-two dimensional sediment transport model, GSTARS4, were conducted in this study using various methods for the determination of recovery factor proposed by previous researches. Simulated results of a reservoir geometric change were sensitive to the selection of recovery factors. It was found that the recovery factor as a function of sediment size provided the most reasonable result. A functional relationship between recovery factor and sediment size was determined by comparing simulated and measured reservoir geometric change. Coarse sediment has small value of recovery factor.

  19. Analytical methods for determination of terbinafine hydrochloride in pharmaceuticals and biological materials$

    Institute of Scientific and Technical Information of China (English)

    Basavaiah Kanakapura n; Vamsi Krishna Penmatsa

    2016-01-01

    Terbinafine is a new powerful antifungal agent indicated for both oral and topical treatment of myco-sessince. It is highly effective in the treatment of determatomycoses. The chemical and pharmaceutical analysis of the drug requires effective analytical methods for quality control and pharmacodynamic and pharmacokinetic studies. Ever since it was introduced as an effective antifungal agent, many methods have been developed and validated for its assay in pharmaceuticals and biological materials. This article reviews the various methods reported during the last 25 years.

  20. Separation Technique for the Determination of Highly Polar Metabolites in Biological Samples

    Directory of Open Access Journals (Sweden)

    Yusuke Iwasaki

    2012-08-01

    Full Text Available Metabolomics is a new approach that is based on the systematic study of the full complement of metabolites in a biological sample. Metabolomics has the potential to fundamentally change clinical chemistry and, by extension, the fields of nutrition, toxicology, and medicine. However, it can be difficult to separate highly polar compounds. Mass spectrometry (MS, in combination with capillary electrophoresis (CE, gas chromatography (GC, or high performance liquid chromatography (HPLC is the key analytical technique on which emerging "omics" technologies, namely, proteomics, metabolomics, and lipidomics, are based. In this review, we introduce various methods for the separation of highly polar metabolites.

  1. Biological determination of the variation of fast-neutron field quality with depth, RBE, and OER

    International Nuclear Information System (INIS)

    The biological effectiveness of two cyclotron-produced fast neutron fields (E/sub n/ approximately 3.5 and 7 MeV) has been studied as a function of depth within a water phantom. Aerobic and hypoxic HeLa S3 cell survival data were obtained at depths of 2 and 12 cm and compared with those measured in a 60Co gamma ray field. Although the resulting survival curves show a small decrease in sensitivity with increasing depth, the oxygen enhancement ratio remains constant and has a value of 1.8 +- 0.1 in both fields. (U.S.)

  2. Gender differences in stress response: Role of developmental and biological determinants

    Directory of Open Access Journals (Sweden)

    Rohit Verma

    2011-01-01

    Full Text Available Stress response is associated with manifestations of various psychosomatic and psychiatric disorders. Hence, it is important to understand the underlying mechanisms that influence this association. Moreover, men and women tend to react differently with stress-both psychologically and biologically. These differences also need to be studied in order to have a better understanding in the gender difference observed for many disorders, which are likely to be contributed by the gender difference in stress reactivity and responses. Such an understanding would have a significant impact on our understanding about how adult health is set during early life and how adult disease could be prevented in men and women.

  3. Biological determinants of plant and crop productivity of flax (Linum usitatissimum L.)

    OpenAIRE

    Tadeusz Zając; Andrzej Oleksy; Agnieszka Klimek-Kopyra; Bogdan Kulig

    2012-01-01

    In Poland the cultivation of the fibrous form of flax (Linum usitatissimum L.) is dying out, but the acreage of its oilseed form, linseed, which provides seed (Semen lini) used in therapy and being a source of -linolenic acid, is expanding. Nowadays, linseed is grown in 64 countries of the world, but yield levels in these countries vary greatly. Under European conditions, seed yield of linseed shows high variation, which is evidence of little knowledge of the biology of this plant and the lac...

  4. Using ANN to predict E. coli accumulation in coves based on interaction amongst various physical, chemical and biological factors

    Science.gov (United States)

    Dwivedi, D.; Mohanty, B. P.; Lesikar, B. J.

    2008-12-01

    The accumulation of Escherichia Coli (E. coli) in canals, coves and streams is the result of a number of interacting processes operating at multiple spatial and temporal scales. Fate and transport of E. coli in surface water systems is governed by different physical, chemical, and biological processes. Various models developed to quantify each of these processes occurring at different scales are not so far pooled into a single predictive model. At present, very little is known about the fate and transport of E. coli in the environment. We hypothesize that E. coli population heterogeneity in canals and coves is affected by physical factors (average stream width and/ depth, secchi depth, flow and flow severity, day since precipitation, aquatic vegetation, solar radiation, dissolved and total suspended solids etc.); chemical factors (basic water quality, nutrients, organic compounds, pH, and toxicity etc.); and biological factors (type of bacterial strain, predation, and antagonism etc.). The specific objectives of this study are to: (1) examine the interactions between E. coli and various coupled physical, chemical and biological factors; (2) examine the interactions between E. coli and toxic organic pollutants and other pathogens (viruses); and (3) evaluate qualitatively the removal efficiency of E. coli. We suggest that artificial neural networks (ANN) may be used to provide a possible solution to this problem. To demonstrate the application of the approach, we develop an ANN representing E. coli accumulation in two polluted sites at Lake Granbury in the upper part of the Brazos River in North Central Texas. The graphical structure of ANN explicitly represents cause- and-effect relationship between system variables. Each of these relationships can then be quantified independently using an approach suitable for the type and scale of information available. Preliminary results revealed that E. coli concentrations in canals show seasonal variations regardless of change

  5. An overview of the analytical methods for the determination of organic ultraviolet filters in biological fluids and tissues

    International Nuclear Information System (INIS)

    Highlights: ► Papers describing the determination of UV filters in fluids and tissues are reviewed. ► Matrix complexity and low amounts of analytes require effective sample treatments. ► The published papers do not cover the study of all the substances allowed as UV filters. ► New analytical methods for UV filters determination in these matrices are encouraged. - Abstract: Organic UV filters are chemical compounds added to cosmetic sunscreen products in order to protect users from UV solar radiation. The need of broad-spectrum protection to avoid the deleterious effects of solar radiation has triggered a trend in the cosmetic market of including these compounds not only in those exclusively designed for sun protection but also in all types of cosmetic products. Different studies have shown that organic UV filters can be absorbed through the skin after topical application, further metabolized in the body and eventually excreted or bioaccumulated. These percutaneous absorption processes may result in various adverse health effects, such as genotoxicity caused by the generation of free radicals, which can even lead to mutagenic or carcinogenic effects, and estrogenicity, which is associated with the endocrine disruption activity caused by some of these compounds. Due to the absence of official monitoring protocols, there is a demand for analytical methods that enable the determination of UV filters in biological fluids and tissues in order to retrieve more information regarding their behavior in the human body and thus encourage the development of safer cosmetic formulations. In view of this demand, there has recently been a noticeable increase in the development of sensitive and selective analytical methods for the determination of UV filters and their metabolites in biological fluids (i.e., urine, plasma, breast milk and semen) and tissues. The complexity of the biological matrix and the low concentration levels of these compounds inevitably impose sample

  6. An overview of the analytical methods for the determination of organic ultraviolet filters in biological fluids and tissues

    Energy Technology Data Exchange (ETDEWEB)

    Chisvert, Alberto, E-mail: alberto.chisvert@uv.es [Departamento de Quimica Analitica, Facultad de Quimica, Universitat de Valencia, Doctor Moliner St. 50, 46100 Burjassot, Valencia (Spain); Leon-Gonzalez, Zacarias [Unidad Analitica, Instituto de Investigacion Sanitaria Fundacion Hospital La Fe, 46009 Valencia (Spain); Tarazona, Isuha; Salvador, Amparo [Departamento de Quimica Analitica, Facultad de Quimica, Universitat de Valencia, Doctor Moliner St. 50, 46100 Burjassot, Valencia (Spain); Giokas, Dimosthenis [Laboratory of Analytical Chemistry, Department of Chemistry, University of Ioannina, 45110 Ioannina (Greece)

    2012-11-08

    Highlights: Black-Right-Pointing-Pointer Papers describing the determination of UV filters in fluids and tissues are reviewed. Black-Right-Pointing-Pointer Matrix complexity and low amounts of analytes require effective sample treatments. Black-Right-Pointing-Pointer The published papers do not cover the study of all the substances allowed as UV filters. Black-Right-Pointing-Pointer New analytical methods for UV filters determination in these matrices are encouraged. - Abstract: Organic UV filters are chemical compounds added to cosmetic sunscreen products in order to protect users from UV solar radiation. The need of broad-spectrum protection to avoid the deleterious effects of solar radiation has triggered a trend in the cosmetic market of including these compounds not only in those exclusively designed for sun protection but also in all types of cosmetic products. Different studies have shown that organic UV filters can be absorbed through the skin after topical application, further metabolized in the body and eventually excreted or bioaccumulated. These percutaneous absorption processes may result in various adverse health effects, such as genotoxicity caused by the generation of free radicals, which can even lead to mutagenic or carcinogenic effects, and estrogenicity, which is associated with the endocrine disruption activity caused by some of these compounds. Due to the absence of official monitoring protocols, there is a demand for analytical methods that enable the determination of UV filters in biological fluids and tissues in order to retrieve more information regarding their behavior in the human body and thus encourage the development of safer cosmetic formulations. In view of this demand, there has recently been a noticeable increase in the development of sensitive and selective analytical methods for the determination of UV filters and their metabolites in biological fluids (i.e., urine, plasma, breast milk and semen) and tissues. The complexity of

  7. Factors Influencing Academic Performance of Students Enrolled in a Lower Division Cell Biology Core Course

    Science.gov (United States)

    Soto, Julio G.; Anand, Sulekha

    2009-01-01

    Students' performance in two semesters of our Cell Biology course was examined for this study. Teaching strategies, behaviors, and pre-course variables were analyzed with respect to students' performance. Pre-semester and post-semester surveys were administered to ascertain students' perceptions about class difficulty, amount of study and effort…

  8. Modeling LIDAR Detection of Biological Aerosols to Determine Optimum Implementation Strategy

    Energy Technology Data Exchange (ETDEWEB)

    Sheen, David M.; Aker, Pam M.

    2007-09-19

    This report summarizes work performed for a larger multi-laboratory project named the Background Interferent Measurement and Standards project. While originally tasked to develop algorithms to optimize biological warfare agent detection using UV fluorescence LIDAR, the current uncertainties in the reported fluorescence profiles and cross sections the development of any meaningful models. It was decided that a better approach would be to model the wavelength-dependent elastic backscattering from a number of ambient background aerosol types, and compare this with that generated from representative sporulated and vegetative bacterial systems. Calculations in this report show that a 266, 355, 532 and 1064 nm elastic backscatter LIDAR experiment will allow an operator to immediately recognize when sulfate, VOC-based or road dust (silicate) aerosols are approaching, independent of humidity changes. It will be more difficult to distinguish soot aerosols from biological aerosols, or vegetative bacteria from sporulated bacteria. In these latter cases, the elastic scattering data will most likely have to be combined with UV fluorescence data to enable a more robust categorization.

  9. Determination of trace aluminum in biological and water samples by cloud point extraction preconcentration and graphite furnace atomic absorption spectrometry detection

    Energy Technology Data Exchange (ETDEWEB)

    Sang Hongbo [Key Laboratory of Pesticide and Chemical Biology of Ministry of Education, College of Chemistry, Central China Normal University, Wuhan 430079 (China); Liang Pei [Key Laboratory of Pesticide and Chemical Biology of Ministry of Education, College of Chemistry, Central China Normal University, Wuhan 430079 (China)], E-mail: liangpei@mail.ccnu.edu.cn; Du Dan [Key Laboratory of Pesticide and Chemical Biology of Ministry of Education, College of Chemistry, Central China Normal University, Wuhan 430079 (China)

    2008-06-15

    A cloud point extraction (CPE) method for the preconcentration of trace aluminum prior to its determination by graphite furnace atomic absorption spectrometry (GFAAS) has been developed. The CPE method is based on the complex of Al(III) with 1-phenyl-3-methyl-4-benzoyl-5-pyrazolone (PMBP), and then entrapped in non-ionic surfactant Triton X-114. PMBP was used not only as chelating reagent in CPE preconcentration, but also as chemical modifier in GFAAS determination. The main factors affecting CPE efficiency, such as pH of sample solution, concentration of PMBP and Triton X-114, equilibration temperature and time, were investigated in detail. An enrichment factor of 37 was obtained for the preconcentration of Al(III) with 10 mL solution. Under the optimal conditions, the detection limit of this method for Al(III) is 0.09 ng mL{sup -1}, and the relative standard deviation is 4.7% at 10 ng mL{sup -1} Al(III) level (n = 7). The proposed method has been applied for determination of trace amount of aluminum in biological and water samples with satisfactory results.

  10. Determination of digitised radiograph magnification factors for pre-operative templating in hip prosthesis surgery

    International Nuclear Information System (INIS)

    With digital radiography development, information technology (IT) companies have developed specific software for templating procedures, requiring individual magnification assessments for each patient. The aim of this study was to determine the mean magnification factor of digital radiographs and to evaluate the possibility of using the mean magnification factor or clinical information in templating. We retrospectively evaluated 100 primary total hip arthroplasty digital radiographs using the femoral head prosthesis as a calliper to determinate the mean magnification factor. Working on the assumption that altitude of the hip during radiograph is decisive in modification of magnification factors, we also looked for a correlation between weight, body mass index (BMI), altitude and magnification factor. The magnification factor was 126% (121-130%). A relationship was found between magnification factor (Mf) and weight (Mf = 7.10-4 x weight (kg) + 1.21), but not BMI. In 98% of cases, if the weight-correlated formula is used, the sizing is correct or the error is ± 1 mm. With the mean method the sizing is correct or within 1 mm in only 78.2% of cases. Levels of accuracy for the mean magnification factor and the weight-correlated formula are not as high as individual assessments using a calliper; however, they could be used in everyday practice where individual magnification factors have not been calculated. (orig.)

  11. Alpha spectroscopic determination of plutonium and uranium in food, biological materials, and soils

    International Nuclear Information System (INIS)

    An alpha-spectrometric method for the plutonium determination which was tested in different samples is described in detail. In particular, this method is capable of determining the very low plutonium levels found in food at present, and allow recoveries of 85-95% of the tracer added. Inorganic samples, such as soil samples for example, can be analyzed by using an abbreviated modification of the method. The measuring preparations show a high degree of spectral purity. Uranium can be separated during the analytical procedure and, after purification, can also be determined alpha-spectrometrically. 90-100% of the uranium are recovered. (orig.)

  12. Determination of Important Topographic Factors for Landslide Mapping Analysis Using MLP Network

    Directory of Open Access Journals (Sweden)

    Mutasem Sh. Alkhasawneh

    2013-01-01

    Full Text Available Landslide is one of the natural disasters that occur in Malaysia. Topographic factors such as elevation, slope angle, slope aspect, general curvature, plan curvature, and profile curvature are considered as the main causes of landslides. In order to determine the dominant topographic factors in landslide mapping analysis, a study was conducted and presented in this paper. There are three main stages involved in this study. The first stage is the extraction of extra topographic factors. Previous landslide studies had identified mainly six topographic factors. Seven new additional factors have been proposed in this study. They are longitude curvature, tangential curvature, cross section curvature, surface area, diagonal line length, surface roughness, and rugosity. The second stage is the specification of the weight of each factor using two methods. The methods are multilayer perceptron (MLP network classification accuracy and Zhou's algorithm. At the third stage, the factors with higher weights were used to improve the MLP performance. Out of the thirteen factors, eight factors were considered as important factors, which are surface area, longitude curvature, diagonal length, slope angle, elevation, slope aspect, rugosity, and profile curvature. The classification accuracy of multilayer perceptron neural network has increased by 3% after the elimination of five less important factors.

  13. Determination relevant breeding criteria by the path and factor analysis in maize

    Directory of Open Access Journals (Sweden)

    Filipović Milomir

    2014-01-01

    Full Text Available In the process of plant breeding the application of relevant breeding criteria is very important. The Path analysis is broadly applied with the aim to define yield components that mostly determine the yield and that can be used as quality breeding criteria. However, the significance of revealed relationships between yield and yield components can be affected by various factors, such as diverse genetic material that is observed, traits included into analysis, environments in which the material is observed, as well as, the applied statistic approach to determine the nature of the relationships itself. The interrelationships of yield and yield components of 15 commercial maize hybrids were observed using the Path and factor analyses. According to results of Path analysis, plant height, ear diameter and grain moisture had highly significant genetic and phenotypic direct effects on grain yield. At the same time, factor analysis points out significant effects of two factors on grain yield. Factor 1 was mostly determined by ear length and number of kernels per row, while grain moisture content, ear and cob diameter mostly determined Factor 2. [Projekat Ministarstva nauke Republike Srbije, br. TR 31068

  14. Critical comparison of radiometric and mass spectrometric methods for the determination of radionuclides in environmental, biological and nuclear waste samples.

    Science.gov (United States)

    Hou, Xiaolin; Roos, Per

    2008-02-11

    The radiometric methods, alpha (alpha)-, beta (beta)-, gamma (gamma)-spectrometry, and mass spectrometric methods, inductively coupled plasma mass spectrometry, accelerator mass spectrometry, thermal ionization mass spectrometry, resonance ionization mass spectrometry, secondary ion mass spectrometry, and glow discharge mass spectrometry are reviewed for the determination of radionuclides. These methods are critically compared for the determination of long-lived radionuclides important for radiation protection, decommissioning of nuclear facilities, repository of nuclear waste, tracer application in the environmental and biological researches, these radionuclides include (3)H, (14)C, (36)Cl, (41)Ca, (59,63)Ni, (89,90)Sr, (99)Tc, (129)I, (135,137)Cs, (210)Pb, (226,228)Ra, (237)Np, (241)Am, and isotopes of thorium, uranium and plutonium. The application of on-line methods (flow injection/sequential injection) for separation of radionuclides and automated determination of radionuclides is also discussed.

  15. Critical comparison of radiometric and mass spectrometric methods for the determination of radionuclides in environmental, biological and nuclear waste samples.

    Science.gov (United States)

    Hou, Xiaolin; Roos, Per

    2008-02-11

    The radiometric methods, alpha (alpha)-, beta (beta)-, gamma (gamma)-spectrometry, and mass spectrometric methods, inductively coupled plasma mass spectrometry, accelerator mass spectrometry, thermal ionization mass spectrometry, resonance ionization mass spectrometry, secondary ion mass spectrometry, and glow discharge mass spectrometry are reviewed for the determination of radionuclides. These methods are critically compared for the determination of long-lived radionuclides important for radiation protection, decommissioning of nuclear facilities, repository of nuclear waste, tracer application in the environmental and biological researches, these radionuclides include (3)H, (14)C, (36)Cl, (41)Ca, (59,63)Ni, (89,90)Sr, (99)Tc, (129)I, (135,137)Cs, (210)Pb, (226,228)Ra, (237)Np, (241)Am, and isotopes of thorium, uranium and plutonium. The application of on-line methods (flow injection/sequential injection) for separation of radionuclides and automated determination of radionuclides is also discussed. PMID:18215644

  16. Implementing a quick method of determining output factors for small irregularly shaped electron fields

    International Nuclear Information System (INIS)

    Full text: Electron beam output factors for small irregularly shaped electron beam cutouts are time consuming to determine, requiring accurate measurements. At the Nepean Cancer Care Centre (NCCC), a computer program was written using the sector weighted integration method to compute the output factors. This poster presents the implementation process undertaken. The output factors for small and irregularly shaped electron beam cutouts for 6 and 9 MeV electrons from Varian 21EX and 2100CD linear accelerators were determined using (1) direct measurement with diode detector in water phantom, and (2) computational method based on sector-weighted integration method. The computational algorithm is implemented into a computer program written in Visual Basic. Output factors for circular cutouts with various diameters ranging from 2cm to 6cm were measured using a diode detector. The output factors obtained and the shape of the irregular cutout were inputted into the computer program. The computed output factors were compared with the measured values. The results from the sector-weighted method of calculating output factors for small and irregularly shaped electron beam cutouts were within ±2% of the measured value. The computational method can reduce the amount of time required to determine the output factors without sacrificing the accuracy of electron beam treatment, whilst also making the process simpler. NCCC has adopted the sector-weighted integration method to determine the output factors for small irregularly shaped electron beam cutouts. The computer program developed for this purpose is fully tested and used for clinical cases. Copyright (2001) Australasian College of Physical Scientists and Engineers in Medicine

  17. Biogeochemical Influences on the Determination of Water Chemistry in a Temperate Forest Basin: Factors Determining the pH value

    Science.gov (United States)

    Ohte, Nobuhito; Tokuchi, Naoko; Suzuki, Masakazu

    1995-01-01

    In order to clarify the mechanism of pH determination in a temperate forest watershed in Japan, intensive hydrochemical observations that included in situ measurement of dissolved pCO2 were carried out in 1991 and 1992. From the variations of observed pCO2 and pH and estimated alkalinity associated with the hydrological process, the factors determining pH were described. There were two hydrological processes which have different determining hydrochemical processes: (1) rainfall and throughfall to infiltration in the soil layer to stable groundwater and (2) stable groundwater to spring water to stream water. In the first process, pH is influenced by infiltration from the low pCO2 layer to the high CO2 layer and by an increase of alkalinity, which is mainly caused by an exchange reaction and chemical weathering. In the shallow soil layer the protons for alkalinity generation are supplied by acid deposits from rainfall and throughfall, microbial acid production, and CO2 dissolution reaction. In the deeper layer an increase of alkalinity caused by Na+ generation becomes remarkable as depth increases. This process is strongly controlled by chemical weathering. In the second process, pH increases with CO2 degassing around the spring point. The alkalinity is kept at the same level as that of the stable groundwater. These results suggests that the biochemically supplied CO2 in soil not only directly controls the pH determination, but also has influences on the alkalinity generation as another determining factor of pH.

  18. Biological stability in drinking water: a regression analysis of influencing factors

    Institute of Scientific and Technical Information of China (English)

    LU Wei; ZHANG Xiao-jian

    2005-01-01

    Some parameters, such as assimilable organic carbon(AOC), chloramine residual, water temperature, and water residence time, were measured in drinking water from distribution systems in a northern city of China. The measurement results illustrate that when chloramine residual is more than 0.3 mg/L or AOC content is below 50 tμg/L, the biological stability of drinking water can be controlled.Both chloramine residual and AOC have a good relationship with Heterotrophic Plate Counts(HPC)(log value), the correlation coefficient was -0.64 and 0.33, respectively. By regression analysis of the survey data, a statistical equation is presented and it is concluded that disinfectant residual exerts the strongest influence on bacterial growth and AOC is a suitable index to assess the biological stability in the drinking water.

  19. [Biological, chemical, and radiation factors in the classification of medical waste].

    Science.gov (United States)

    Rusakov, N V; Korotkova, G I; Orlov, A Iu; Kadyrov, D E

    2011-01-01

    The current classification of medical waste does not consider the sanitary-and-chemical hazard of epidemiologically dangerous and extremely dangerous medical waste (classes B and C). According to the results of the studies performed, the authors propose the improved classification of medical waste, which makes it possible to take into account not only infectious, radiation, and toxicological, but also sanitary-and-chemical hazards (toxicity, carcinogenicity, mutagenicity, and biological activity) of medical waste. PMID:21901883

  20. Critical tests for determination of microbiological quality and biological activity in commercial vermicompost samples of different origins.

    Science.gov (United States)

    Grantina-Ievina, Lelde; Andersone, Una; Berkolde-Pīre, Dace; Nikolajeva, Vizma; Ievinsh, Gederts

    2013-12-01

    The aim of the present paper was to show that differences in biological activity among commercially produced vermicompost samples can be found by using a relatively simple test system consisting of microorganism tests on six microbiological media and soilless seedling growth tests with four vegetable crop species. Significant differences in biological properties among analyzed samples were evident both at the level of microbial load as well as plant growth-affecting activity. These differences were mostly manufacturer- and feedstock-associated, but also resulted from storage conditions of vermicompost samples. A mature vermicompost sample that was produced from sewage sludge still contained considerable number of Escherichia coli. Samples from all producers contained several potentially pathogenic fungal species such as Aspergillus fumigatus, Pseudallescheria boidii, Pseudallescheria fimeti, Pseudallescheria minutispora, Scedosporium apiospermum, Scedosporium prolificans, Scopulariopsis brevicaulis, Stachybotrys chartarum, Geotrichum spp., Aphanoascus terreus, and Doratomyces columnaris. In addition, samples from all producers contained plant growth-promoting fungi from the genera Trichoderma and Mortierella. The described system can be useful both for functional studies aiming at understanding of factors affecting quality characteristics of vermicompost preparations and for routine testing of microbiological quality and biological activity of organic waste-derived composts and vermicomposts. PMID:23504062

  1. A numerical method for determining the strain rate intensity factor under plane strain conditions

    Science.gov (United States)

    Alexandrov, S.; Kuo, C.-Y.; Jeng, Y.-R.

    2016-07-01

    Using the classical model of rigid perfectly plastic solids, the strain rate intensity factor has been previously introduced as the coefficient of the leading singular term in a series expansion of the equivalent strain rate in the vicinity of maximum friction surfaces. Since then, many strain rate intensity factors have been determined by means of analytical and semi-analytical solutions. However, no attempt has been made to develop a numerical method for calculating the strain rate intensity factor. This paper presents such a method for planar flow. The method is based on the theory of characteristics. First, the strain rate intensity factor is derived in characteristic coordinates. Then, a standard numerical slip-line technique is supplemented with a procedure to calculate the strain rate intensity factor. The distribution of the strain rate intensity factor along the friction surface in compression of a layer between two parallel plates is determined. A high accuracy of this numerical solution for the strain rate intensity factor is confirmed by comparison with an analytic solution. It is shown that the distribution of the strain rate intensity factor is in general discontinuous.

  2. Development of a mild mercaptoethanol extraction method for determination of mercury species in biological samples by HPLC-ICP-MS.

    Science.gov (United States)

    Wang, Meng; Feng, Weiyue; Shi, Junwen; Zhang, Fang; Wang, Bing; Zhu, Motao; Li, Bai; Zhao, Yuliang; Chai, Zhifang

    2007-03-30

    A mild, efficient and convenient extraction method of using 2-mercaptoethanol contained extractant solution combined with an incubator shaker for determination of mercury species in biological samples by HPLC-ICP-MS has been developed. The effects of the concentration of 2-mercaptoethanol, the composition of the extractant solution and the shaking time on the efficiency of mercury extraction were evaluated. The optimization experiments indicated that the quantitative extraction of mercury species from biological samples could be achieved by using 0.1% (v/v) HCl, 0.1% (v/v) 2-mercapoethanol and 0.15% (m/v) KCl extractant solution in an incubator shaker for shaking overnight (about 12h) at room temperature. The established method was validated by analysis of various biological certified reference materials, including NRCC DOLT-3 (dogfish liver), IAEA 436 (tuna fish), IAEA MA-B-3/TM (garfish filet), IAEA MA-M-2/TM (mussel tissue), GBW 08193 (bovine liver) and GBW 08572 (prawn). The analytical results of the reference materials were in good agreement with the certified or reference values of both methyl and total mercury, indicating that no distinguishable transformation between mercury species had occurred during the extraction and determination procedures. The limit of detection (LOD) for methyl (CH(3)Hg(+)) and inorganic mercury (Hg(2+)) by the method are both as 0.2microg L(-1). The relative standard deviation (R.S.D.s) for CH(3)Hg(+) and Hg(2+) are 3.0% and 5.8%, respectively. The advantages of the developed extraction method are that (1) it is easy to operate in HPLC-ICP-MS for mercury species determination since the extracted solution can be directly injected into the HPLC column without pH adjustment and (2) the memory effect of mercury in the ICP-MS measurement system can be reduced.

  3. Determination of boron in biological samples for the needs of neutron capture therapy

    International Nuclear Information System (INIS)

    Monitoring the actual concentration of 10B in a patient's blood is a prerequisite for determining the start and length of patient irradiation. The Prompt Gamma Ray Analysis (PGRA) method enables this nuclide to be determined rapidly and reliably within the region of 1 to 100 ppm. In this method, the characteristic line at 478 keV from the nuclear reaction 10B+n → 7Li+α+γ during sample exposure to thermal neutrons is used to determine boron. The facility which has been built up for this purpose comprises, in particular, a large-volume semiconductor detector for recording gamma rays emerging from the radiative neutron capture on the target

  4. A REVIEW OF ENVIRONMENTAL FACTORS DETERMINING TO PROACTIVITY: THE CASE OF THE FOOTWEAR INDUSTRY

    Directory of Open Access Journals (Sweden)

    Jose Carlos Lazaro

    2012-09-01

    Full Text Available This paper reviews literature in order to identify the determinant factors of companies’ environmental proactivity. According to Gonzalez-Benito and Gonzalez-Benito (2006, environmental proactivity demands three practices: planning and organization, operation, and communication. Environmental strategies go on to comment upon several variables that depict internal company features, external factors, and stakeholders pressures. This work discusses these issues using data collected in 2007 from shoe companies selected for in-depth personal interviews and site visits in two different Brazilian states. The empirical results demonstrate that proactive approaches seem clear in companies influenced by stakeholders’ pressure. This is the central determinant factor and it is argued that all the other variables affect either the intensity of this pressure or the company’s capacity to perceive it. All the factors identified herein should be taken into account, at least as control variables, in those studies aiming at explaining and contextualizing environmental strategies.

  5. IAEA quality control study on determining trace elements in biological matrices for air pollution research

    International Nuclear Information System (INIS)

    Analysis of lichens and mosses were routinely performed by 17 laboratories from 15 countries around the world, participating in a project coordinated by the International Atomic Energy Agency (IAEA). To improve and control the quality of such determinations, the IAEA organized a two-round interlaboratory exercise, which allowed the detection and removal of most of the pitfalls observed in the determination of 27 elements. The application of instrumental neutron activation analysis helped reveal poor recoveries in some laboratories due to incomplete digestion for a number of elements. The exercise emphasized the importance of achieving comparability of chemical measurements to a recognized reference. (author)

  6. Radiation-induced cardiac damage in early left breast cancer patients: Risk factors, biological mechanisms, radiobiology, and dosimetric constraints

    International Nuclear Information System (INIS)

    Today there is general awareness of the potential damage to the heart in left-sided (more than in right-sided) breast cancer radiotherapy (RT). Historical changes in tumor and heart doses are presented here along with the impact of different RT techniques and volumes. Individual and pharmacological risk factors are also examined with respect to radiation damage. The biological mechanisms of harm are only partially understood, such as the radiobiology of heart damage due to the presence of various radiosensitive structures and their topographic heterogeneity. Furthermore, individual variability may expose patients to higher or lower risks of late cardiac damage or death. Damage mechanisms and radiobiological characteristics in heart irradiation are presented in relation to dosimetric and biological parameters.

  7. In vitro sun protection factor determination of herbal oils used in cosmetics

    OpenAIRE

    Chanchal Deep Kaur; Swarnlata Saraf

    2010-01-01

    The aim of this study was to evaluate ultraviolet (UV) absorption ability of volatile and nonvolatile herbal oils used in sunscreens or cosmetics and express the same in terms of sun protection factor (SPF) values. Sun protection factor is a laboratory measure of the effectiveness of sunscreen; the higher the SPF, the more protection a sunscreen offers against the ultraviolet radiations causing sunburn. The in vitro SPF is determined according to the spectrophotometric method of Mansur et al....

  8. Supplier selection or collaboration? Determining factors of performance improvement when outsourcing manufacturing

    OpenAIRE

    Dabhilkar, Mandar; Bengtsson, Lars; Haartman, Robin von; Åhlström, Pär

    2009-01-01

    An empirical study was designed to determine factors of performance improvement when outsourcing manufacturing. Findings from a survey of 136 manufacturing plants in Sweden show that most of them achieve their outsourcing motives, but not without trade-offs. Factors of performance improvements such as economies of scale or operations in low-cost countries can improve one performance dimension, such as product cost, yet negatively impact volume flexibility, speed or product innovation. The res...

  9. A Method to Determine the Slip Factor of Centrifugal Pumps through Experiment

    Science.gov (United States)

    Zhang, Yu-Liang; Zhu, Zu-Chao; Dou, Hua-Shu; Cui, Bao-Ling; Li, Yi; Xiao, Jun-Jian

    2015-04-01

    In this paper, a method to determine the slip factor of centrifugal impellers is proposed based on the experimental result of the external performance of centrifugal pumps. This proposed method is superior to the conventional experimental method, which needs not to measure the flow parameters at impeller outlet. The results show that the present method can be used to obtain the slip factor at offdesign condition in a wide range of flow rate besides at the design point.

  10. Housing Price Determinants in Malaysia– in the Aspect of Macroeconomic Factors

    OpenAIRE

    Gan, Hwa Fern

    2008-01-01

    Housing is widely connected to economy factors, and its complexity cause difficulties in prediction. Therefore it is essential to understand the mechanism underlying the housing market. This study suggests that fundamental macroeconomic factors, i.e. Gross Domestic Product, Lending Rate, Unemployment Rate, Construction Cost and Consumer Price Indices play important roles in determining the house prices. In this paper, econometric methodology has been adopted to study the relationship between ...

  11. Terbium sensitized spectrofluorimetric determination of deferasirox in biological fluids and tablet formulations

    International Nuclear Information System (INIS)

    Complete text of publication follows. It is well known that some trivalent lanthanide ions in an aqueous medium at ambient temperature have weak fluorescence properties. However, when these ions in particular Eu3+ and Tb3+ are chelated with ligands that have a broad intense absorption band their fluorescence can be dramatically enhanced. This phenomenon has been of great interest for the trace determination of lanthanide ions and a variety of medically important compounds. A rapid, simple and sensitive spectrofluorimetric method was developed and validated for the determination of deferasirox in urine, serum and tablet samples based on the formation of Terbium (Tb+3) - deferasirox complex with the excitation and emission wavelengths of 328 and 545 nm. The optimum conditions for the determination of deferasirox were investigated considering the effects of various affecting parameters. The method was quantitatively evaluated in terms of linearity, recovery, reproducibility and limit of detection. Under the optimal conditions, the fluorescence intensities were linear with the concentration of deferasirox in the range of 5 x 10-9 - 5 x 10-6 M, with a detection limit of 1.5 x 10-9 M and the relative standard deviations of 1.1 - 2.3% . Linearity, reproducibility, recovery and limit of detection made the method suitable for the determination of deferasirox in urine, serum and tablets samples.

  12. Determining Enzyme Kinetics for Systems Biology with Nuclear Magnetic Resonance Spectroscopy

    Directory of Open Access Journals (Sweden)

    Johann J. Eicher

    2012-11-01

    Full Text Available Enzyme kinetics for systems biology should ideally yield information about the enzyme’s activity under in vivo conditions, including such reaction features as substrate cooperativity, reversibility and allostery, and be applicable to enzymatic reactions with multiple substrates. A large body of enzyme-kinetic data in the literature is based on the uni-substrate Michaelis–Menten equation, which makes unnatural assumptions about enzymatic reactions (e.g., irreversibility, and its application in systems biology models is therefore limited. To overcome this limitation, we have utilised NMR time-course data in a combined theoretical and experimental approach to parameterize the generic reversible Hill equation, which is capable of describing enzymatic reactions in terms of all the properties mentioned above and has fewer parameters than detailed mechanistic kinetic equations; these parameters are moreover defined operationally. Traditionally, enzyme kinetic data have been obtained from initial-rate studies, often using assays coupled to NAD(PH-producing or NAD(PH-consuming reactions. However, these assays are very labour-intensive, especially for detailed characterisation of multi-substrate reactions. We here present a cost-effective and relatively rapid method for obtaining enzyme-kinetic parameters from metabolite time-course data generated using NMR spectroscopy. The method requires fewer runs than traditional initial-rate studies and yields more information per experiment, as whole time-courses are analyzed and used for parameter fitting. Additionally, this approach allows real-time simultaneous quantification of all metabolites present in the assay system (including products and allosteric modifiers, which demonstrates the superiority of NMR over traditional spectrophotometric coupled enzyme assays. The methodology presented is applied to the elucidation of kinetic parameters for two coupled glycolytic enzymes from Escherichia coli

  13. Optimization of Determinant Factors of Satellite Electrical Power System with Particle Swarm Optimization (PSO Algorithm

    Directory of Open Access Journals (Sweden)

    Mojtaba Biglarahmadi

    2014-03-01

    Full Text Available Weight and dimension, cost, and performance are determinant factors for design, fabrication, and launch the satellites which are related to the mission type of the satellites. Each satellite includes several subsystems such as Electrical Power Subsystem (EPS, Navigation Subsystem, Thermal Subsystem, etc. The purpose of this paper is to optimize these determinant factors by Particle Swarm Optimization (PSO algorithm, for Electrical Power Subsystem. This paper considers the effects of selecting various types of Photovoltaic (PV cells and batteries on weight and dimension, cost, and performance of the satellite. We have used two various types of PVs and two various type of batteries in optimization of the Electrical Power Subsystem (EPS

  14. Determination of scatter factor parameters and electron disequilibrium for monoenergetic photon beams.

    Science.gov (United States)

    McDonough, J; Bloch, P; Bjärngard, B E

    1999-02-01

    The tissue-phantom-ratio (TPR) is expressed as the product of the phantom scatter factor (SF), an electron disequilibrium factor, and an attenuation factor, equal to the zero-area TPR. The scatter factor, as a function of depth d and field size s, has been described by two parameters a and w, SF(d,s) = 1 + asd/(ws + d). We have determined the parameters a and w for 20 monoenergetic photon beams between 1 and 20 MeV. Pencil-beam energy-deposition kernels were obtained using Monte Carlo simulations. The kernels were used to calculate broad-beam depth-dose data, which were converted to TPR and fitted to the equation above using an iterative search over a-w space. The parameter a is nearly equal to the attenuation coefficient for all energies while the parameter w increases with energy. The resulting a and w compare favorably to values determined for clinical photon beams, as a function of the measured attenuation coefficient. With the scatter factor determined, we isolated the electron disequilibrium factor for each monoenergetic beam. It can be characterized as a quadratic function of the depth. The coefficients of the quadratic function can be related to the range of the most energetic secondary electron produced. PMID:10076974

  15. The basics of experimental determination of the Fano factor in intrinsic semiconductors

    International Nuclear Information System (INIS)

    Intrinsic semiconductors such as High Purity Germanium Detectors are exceptional X-ray and gamma-ray detectors because of their large sizes and small band gap. They are used for fundamental scientific researches, nuclear material safeguards and security, environmental protection, and human health and safety. The fundamental limit of the energy resolution of a semiconductor detector is determined by variance in the number of electron-hole pairs produced by X-rays in detector volume. The principal characteristic of material for using as semiconductor detector is the Fano factor that determines the fluctuation in the number of electron-hole pairs. Now, all existing methods of experimental determination of the Fano factor in semiconductors are based on the subtraction of electronic noise from the signal variance. In this work, I propose the method of experimental determination of the Fano factor in a planar semiconductor detector based on dependences of the mean amplitude and the energy resolution on the electric field. It was shown that inverse electric field expansion of these dependences allow determining the Fano factor, electron mobility lifetime product, and relative variance of electron lifetime due to inhomogeneous charge transport in semiconductor material. The important advantage of the proposed method is independence on detector electronic noise. (authors)

  16. How Events at the Nano/Bio Interface Determine Good and Adverse Biological Outcomes

    Science.gov (United States)

    Nel, Andre

    2014-03-01

    We have come to recognize that much of biology is executed at the nanoscale level, therefore providing a rational approach to using discovery about the structure and function of engineered nanomaterials (ENMs) at the nano/bio interface for interrogation of disease, diagnosis, treatment, and imaging at levels of sophistication not possible before. Moreover, the behavior of ENM's at the nano/bio interface also constitutes the basis for hazard generation and is therefore key for understanding the safety assessment and safer design of nanomaterials. In this overview, I will discuss how discovery at the molecular, cellular, organ and systemic nano/bio interfaces has helped us to my progress progress in the fields of nanomedicine and nanotoxicology. I will explain how the physicochemical properties of nanomaterials relate to nanoscale interactions at the membrane, intracellular organelles, tissues and organs in response to exposure to a variety of commercial ENMs as well as for therapeutic nanocarriers. I will delineate how the use of high throughput screening to establish structure-activity relationships can be used for the design of improved nanocarriers for cancer treatment as well as hazard and risk ranking of large categories of commercial ENMs on their way to the marketplace.

  17. Biological determinants of plant and crop productivity of flax (Linum usitatissimum L.

    Directory of Open Access Journals (Sweden)

    Tadeusz Zając

    2012-12-01

    Full Text Available In Poland the cultivation of the fibrous form of flax (Linum usitatissimum L. is dying out, but the acreage of its oilseed form, linseed, which provides seed (Semen lini used in therapy and being a source of -linolenic acid, is expanding. Nowadays, linseed is grown in 64 countries of the world, but yield levels in these countries vary greatly. Under European conditions, seed yield of linseed shows high variation, which is evidence of little knowledge of the biology of this plant and the lack of precise cultivation solutions in agricultural technologies used. A major reason is the difficulty in obtaining optimal crop density. A sparse crop results in low above-ground biomass yield, which is translated into insufficient crop yields. The selection of highly productive domestic and foreign varieties can partially increase linseed yield; apart from some domestic varieties, the Canadian cultivar 'Flanders' and the Hungarian cultivar 'Barbara' are positive examples in this respect. There is a possibility of effective selection at early stages of linseed breeding, which bodes well for the prospect of obtaining highly productive varieties with normal or very low -linolenic acid content.

  18. Characteristics of the biologically active 35-kDa metalloprotease virulence factor from Listeria monocytogenes

    NARCIS (Netherlands)

    Coffey, A; van den Burg, B; Veltman, R; Abee, T

    2000-01-01

    Listeria monocytogenes, a facultative intracellular pathogen, synthesizes an extracellular protease which is responsible for the maturation of phosphatidylcholine phospholipase C (lecithinase), a virulence factor involved in cell-to-cell spread. This work describes the environmental parameters neces

  19. Mechanistic and biological significance of DNA methyltransferase 1 upregulated by growth factors in human hepatocellular carcinoma.

    Science.gov (United States)

    Fang, Qin-Liang; Yin, Yi-Rui; Xie, Cheng-Rong; Zhang, Sheng; Zhao, Wen-Xiu; Pan, Chao; Wang, Xiao-Min; Yin, Zhen-Yu

    2015-02-01

    Dysregulation of growth factor signaling plays a pivotal role in controlling the malignancy phenotype and progression of hepatocellular carcinoma (HCC). However, the precise oncogenic mechanisms underlying transcription regulation of certain tumor suppressor genes (TSGs) by growth factors are poorly understood. In the present study, we report a novel insulin-like growth factor 1 (IGF1) pathway that mediates de novo DNA methylation and TSG (such as DLC1 and CHD5) silencing by upregulation of the DNA methyltransferase 1 (DNMT1) via an AKT/β-transducin repeat-containing protein (βTrCP)-mediated ubiquitin-proteasome pathway in HCC. Analysis of DNA methylation in CpG islands of target genes revealed high co-localization of DNMT1 and DNMT3B on the promoters of TSGs associated with enhanced CpG hypermethylation. Our results point to a novel epigenetic mechanism for growth factor-mediated repression of TSG transcription that involves DNA methylation. PMID:25420499

  20. Biology of Bone Tissue: Structure, Function, and Factors That Influence Bone Cells

    OpenAIRE

    2015-01-01

    Bone tissue is continuously remodeled through the concerted actions of bone cells, which include bone resorption by osteoclasts and bone formation by osteoblasts, whereas osteocytes act as mechanosensors and orchestrators of the bone remodeling process. This process is under the control of local (e.g., growth factors and cytokines) and systemic (e.g., calcitonin and estrogens) factors that all together contribute for bone homeostasis. An imbalance between bone resorption and formation can res...

  1. Exposure factors for marine eutrophication impacts assessment based on a mechanistic biological model

    DEFF Research Database (Denmark)

    Cosme, Nuno Miguel Dias; Koski, Marja; Hauschild, Michael Zwicky

    2015-01-01

    ). This pathway is typical of marine eutrophication. A model is proposed to mechanistically estimate the response of coastal marine ecosystems to N inputs. It addresses the biological processes of nutrient-limited primary production (PP), metazoan consumption, and bacterial degradation, in four distinct sinking...... is essential to estimate a marine eutrophication impacts indicator in Life Cycle Impact Assessment (LCIA) of anthropogenic-N emissions. Every relevant process was modelled and the uncertainty of the driving parameters considered low suggesting valid applicability in characterisation modelling in LCIA....

  2. Affinity of Drugs and Small Biologically Active Molecules to Carbon Nanotubes: A Pharmacodynamics and Nanotoxicity Factor?

    OpenAIRE

    Liu, John; Yang, Liu; Hopfinger, Anton J.

    2009-01-01

    The MM-PBSA MD method was used to estimate the affinity, as represented by log kb, of each of a variety of biologically active molecules to a carbon nanotube in an aqueous environment. These ligand-receptor binding simulations were calibrated by first estimating the log kb values for eight ligands to human serum albumin, HSA, whose log kb values have been observed. A validation linear correlation equation was established [R2 = 0.888 Q2 = 0.603] between the observed and estimated log kb values...

  3. A brief discussion on the biological factors in the acquisition of language

    Directory of Open Access Journals (Sweden)

    Ronivaldo Braz da Silva

    2007-11-01

    Full Text Available The understanding of how language is acquired and the role the brain plays in the language acquisition process are crucial because the development of language is one of the most important factcrs in human development. The analysis of language development is intrinsically connected with one's awareness of how human beings or human brains perceive, learn, control, and coordinate elaborate behaviour. The study of language development, therefore, involves research on motor, perceptual, and cognitive development. This paper reviews the three major theories of language acquisition, namely, behaviouristic, psycholinguistic, and interactionistic and examines the biological component of language acquisition and the brain's role in the language development process.

  4. Humic substances biological activity at the plant-soil interface: from environmental aspects to molecular factors.

    Science.gov (United States)

    Trevisan, Sara; Francioso, Ornella; Quaggiotti, Silvia; Nardi, Serenella

    2010-06-01

    Humic substances (HS) represent the organic material mainly widespread in nature. HS have positive effects on plant physiology by improving soil structure and fertility and by influencing nutrient uptake and root architecture. The biochemical and molecular mechanisms underlying these events are only partially known. HS have been shown to contain auxin and an "auxin-like" activity of humic substances has been proposed, but support to this hypothesis is fragmentary. In this review article, we are giving an overview of available data concerning molecular structures and biological activities of humic substances, with special emphasis on their hormone-like activities. PMID:20495384

  5. Profiling healthy eaters. Determining factors that predict healthy eating practices among Dutch adults.

    Science.gov (United States)

    Swan, Emily; Bouwman, Laura; Hiddink, Gerrit Jan; Aarts, Noelle; Koelen, Maria

    2015-06-01

    Research has identified multiple factors that predict unhealthy eating practices. However what remains poorly understood are factors that promote healthy eating practices. This study aimed to determine a set of factors that represent a profile of healthy eaters. This research applied Antonovsky's salutogenic framework for health development to examine a set of factors that predict healthy eating in a cross-sectional study of Dutch adults. Data were analyzed from participants (n = 703) who completed the study's survey in January 2013. Logistic regression analysis was performed to test the association of survey factors on the outcome variable high dietary score. In the multivariate logistic regression model, five factors contributed significantly (p eating, and self-efficacy for healthy eating. Findings complement what is already known of the factors that relate to poor eating practices. This can provide nutrition promotion with a more comprehensive picture of the factors that both support and hinder healthy eating practices. Future research should explore these factors to better understand their origins and mechanisms in relation to healthy eating practices.

  6. Determining Factors on CEO Turnover and Its Impact on Financial Performance in Turkey [Turkish

    Directory of Open Access Journals (Sweden)

    Mesut Doğan

    2016-04-01

    Full Text Available The main responsibility of the CEO is to create and execute effective strategies that will achieve the goals and objectives determined in line with the company’s vision and mission.The purpose of this study is to determine financial factors that determine CEO turnover and to determine the effects of CEO turnover on the financial performance of the firms traded in Istanbul Stock Exchange (BIST. In the research, data from 136 firms trading in the BIST Manufacturing Industry Index between the dates 2004-2012 was used. In the empirical analysis, logistic regression method was used with the purpose of determining the factors causing CEO turnover. The paired t-test was used for determining the differences before and after the CEO turnover periods. At the end of the analysis; it was determined that reduction of accounting and market based performance indicators; increase of the debt burden, decrease of the sales and assets of BIST Manufacturing Industry Index firms increase the probability of CEO turnover. However, it was determined that CEO turnover adversely affects the companies’ profitability.

  7. Terbium-sensitized luminescence optosensor for the determination of norfloxacin in biological fluids

    Energy Technology Data Exchange (ETDEWEB)

    Martinez, E.J. Llorent [Department of Physical and Analytical Chemistry, Faculty of Experimental Sciences, University of Jaen, Paraje Las Lagunillas, E-23071 Jaen (Spain); Reyes, J.F. Garcia [Department of Physical and Analytical Chemistry, Faculty of Experimental Sciences, University of Jaen, Paraje Las Lagunillas, E-23071 Jaen (Spain); Barrales, P. Ortega [Department of Physical and Analytical Chemistry, Faculty of Experimental Sciences, University of Jaen, Paraje Las Lagunillas, E-23071 Jaen (Spain); Diaz, A. Molina [Department of Physical and Analytical Chemistry, Faculty of Experimental Sciences, University of Jaen, Paraje Las Lagunillas, E-23071 Jaen (Spain)]. E-mail: amolina@ujaen.es

    2005-03-14

    The use of a flow through solid phase terbium-sensitized luminescence system is described for the determination of the widely used fluoroquinolone norfloxacin. A chelate between the terbium ion and the analyte is formed online previously to the sample injection into the carrier stream. Then the chelate is transported towards the flow-through cell, where it is retained on a cationic Sephadex resin packed in the cell, developing the corresponding luminescence signal. Afterwards, an ethylenediaminetetraacetic acid solution was used as eluting agent, in order to regenerate the sensing zone. The system has been satisfactorily applied to the determination of norfloxacin in human urine and serum, without the need of a pre-treatment. The response was linear in the range 10-150 ng ml{sup -1}. The detection and quantification limits were 1.5 and 5 ng ml{sup -1}, respectively and the R.S.D. 1.82%.

  8. Study of performance characteristics of a radiochemical method to determine uranium in biological samples

    International Nuclear Information System (INIS)

    In this paper is described a methodology to calculate detection limit (Ld), quantification level (Lq) and minimum detectable activity (MDA) in a radiochemical method for determination of uranium in urine samples. The concentration is measured by fluorimetry and alpha gross activity using liquid scintillation counting (LSC). The calculation of total propagated uncertainty on a spike sample is presented. Furthermore, the major sources of uncertainty and percentage contribution in both measurements are assessed. (author)

  9. A colorimetric determination of boron in biological sample for boron neutron capture therapy (BNCT)

    International Nuclear Information System (INIS)

    The boron neutron capture therapy (BNCT) has shown better prognosis in the treatment of glyemas and gluoblastomas grade III and IV than other therapies. During the treatment the levels of Na210B12H11SH must be known in several compartiments of the organism and with this purpose the method of colorimetric determination of boron using curcumine was established. This method is simple, reprodutible and adequate sensitivity for this control. (author)

  10. In vivo and in vitro techniques to determine the biological activity of food allergens

    DEFF Research Database (Denmark)

    Poulsen, Lars K.

    2001-01-01

    -allergic individual. Several methods are discussed for determination of potency including the double-blinded placebo-controlled food challenge, skin testing, in vitro effector cell assays such as basophil histamine release, and IgE-based techniques such as RAST and RAST inhibition. No reliable methods have yet been...... developed which can predict the allergenic potential of a food or a food allergen. The progress in the areas of stability studies and animal models for food allergy are discussed....

  11. Sensitive determination of domperidone in biological fluids using a conductive polymer modified glassy carbon electrode

    International Nuclear Information System (INIS)

    A simple and sensitive method for domperidone (DP) determination has been developed by electropolymerizing a polymer film on the surface of glassy carbon electrode (GCE) in acidic solution using cyclic voltammetry. The modified sensor was characterized by Field Emission Scanning Electron Microscopy (FE-SEM) and Electrochemical Impedance Spectroscopy (EIS). The electrochemical measurements were carried out using square wave voltammetry and cyclic voltammetry. The modified sensor exhibited an excellent catalytic response towards the oxidation of DP with a well-defined oxidation peak at 840 mV. The modified sensor exhibited linear calibration curve for DP over a concentration range of 0.1 μM to 100 μM in phosphate buffer solution of pH 7.2 with detection limit of 12.0 nM. The sensor was capable to determine DP effectively without any interference from the common metabolites like ascorbic acid, uric acid, xanthine and hypoxanthine. The analytical utilities of the sensor have been demonstrated by determining the DP in human fluids and pharmaceutical samples. Further, the modified sensor displayed voltammetric responses with high sensitivity, good selectivity and reproducibility which make it suitable for clinical diagnosis

  12. Evaluation of some procedures relevant to the determination of trace elemental components in biological materials by destructive neutron activation analysis

    Energy Technology Data Exchange (ETDEWEB)

    Berry, D.L.

    1979-01-01

    The development of a simplified procedure for the analysis of biological materials by destructive neutron activation analysis (DNAA) is described. The sample manipulations preceding gamma ray assay were investigated as five specific stages of processing: (1) pre-irradiation treatment; (2) sample irradiation; (3) removal of the organic matrix; (4) removal of interfering radioactivities; and (5) concentration and separation of analyte activities. Each stage was evaluated with respect to susceptibility to sample contamination, loss of trace elemental components, and compatibility with other operations in the overall DNAA procedures. A complete DNAA procedure was proposed and evaluated for the analysis of standard bovine liver and blood samples. The DNAA system was effective for the determination of As, Cu, Fe, Hg, Mo, Rb, Sb, Se, and Zn without yield determinations and with a minimum turn-around time of approximately 3 days.

  13. Evaluation of some procedures relevant to the determination of trace elemental components in biological materials by destructive neutron activation analysis

    International Nuclear Information System (INIS)

    The development of a simplified procedure for the analysis of biological materials by destructive neutron activation analysis (DNAA) is described. The sample manipulations preceding gamma ray assay were investigated as five specific stages of processing: (1) pre-irradiation treatment; (2) sample irradiation; (3) removal of the organic matrix; (4) removal of interfering radioactivities; and (5) concentration and separation of analyte activities. Each stage was evaluated with respect to susceptibility to sample contamination, loss of trace elemental components, and compatibility with other operations in the overall DNAA procedures. A complete DNAA procedure was proposed and evaluated for the analysis of standard bovine liver and blood samples. The DNAA system was effective for the determination of As, Cu, Fe, Hg, Mo, Rb, Sb, Se, and Zn without yield determinations and with a minimum turn-around time of approximately 3 days

  14. Determining the Relationship between U.S. County-Level Adult Obesity Rate and Multiple Risk Factors by PLS Regression and SVM Modeling Approaches

    Directory of Open Access Journals (Sweden)

    Chau-Kuang Chen

    2015-02-01

    Full Text Available Data from the Center for Disease Control (CDC has shown that the obesity rate doubled among adults within the past two decades. This upsurge was the result of changes in human behavior and environment. Partial least squares (PLS regression and support vector machine (SVM models were conducted to determine the relationship between U.S. county-level adult obesity rate and multiple risk factors. The outcome variable was the adult obesity rate. The 23 risk factors were categorized into four domains of the social ecological model including biological/behavioral factor, socioeconomic status, food environment, and physical environment. Of the 23 risk factors related to adult obesity, the top eight significant risk factors with high normalized importance were identified including physical inactivity, natural amenity, percent of households receiving SNAP benefits, and percent of all restaurants being fast food. The study results were consistent with those in the literature. The study showed that adult obesity rate was influenced by biological/behavioral factor, socioeconomic status, food environment, and physical environment embedded in the social ecological theory. By analyzing multiple risk factors of obesity in the communities, may lead to the proposal of more comprehensive and integrated policies and intervention programs to solve the population-based problem.

  15. A new cloud point extraction procedure for determination of inorganic antimony species in beverages and biological samples by flame atomic absorption spectrometry.

    Science.gov (United States)

    Altunay, Nail; Gürkan, Ramazan

    2015-05-15

    A new cloud-point extraction (CPE) for the determination of antimony species in biological and beverages samples has been established with flame atomic absorption spectrometry (FAAS). The method is based on the fact that formation of the competitive ion-pairing complex of Sb(III) and Sb(V) with Victoria Pure Blue BO (VPB(+)) at pH 10. The antimony species were individually detected by FAAS. Under the optimized conditions, the calibration range for Sb(V) is 1-250 μg L(-1) with a detection limit of 0.25 μg L(-1) and sensitive enhancement factor of 76.3 while the calibration range for Sb(III) is 10-400 μg L(-1) with a detection limit of 5.15 μg L(-1) and sensitive enhancement factor of 48.3. The precision as a relative standard deviation is in range of 0.24-2.35%. The method was successfully applied to the speciative determination of antimony species in the samples. The validation was verified by analysis of certified reference materials (CRMs).

  16. Trends in selected biological risk factors for cardiovascular diseases in the Danish MONICA population, 1982-1992

    DEFF Research Database (Denmark)

    Gerdes, Lars Ulrik; Brønnum-Hansen, H; Madsen, Mette;

    2000-01-01

    Data from 6695 men and women of ages 30, 40, 50, and 60 years, examined in the Danish WHO MONICA surveys in 1982-84, in 1986-87, and in 1991-92, were analyzed to estimate secular trends in body height and weight, blood pressure, and serum total, HDL-, and LDL-cholesterol, and triglyceride. Body......, systolic blood pressures, total- and LDL cholesterol and triglyceride did not change. The levels of biological risk factors in the Danish WHO MONICA study population did not show trends during the 1980s that help explain the declining incidence of myocardial infarction in the population....

  17. The epidermal growth factor receptors as biological targets in penile cancer.

    Science.gov (United States)

    Di Lorenzo, Giuseppe; Buonerba, Carlo; Ferro, Matteo; Calderoni, Giuseppe; Bozza, Giovanni; Federico, Piera; Tedesco, Beatrice; Ruggieri, Vitalba; Aieta, Michele

    2015-04-01

    Penile cancer is a rare disease, with an incidence that is higher in less developed countries and is in the range of 1 - 10 per 100000 men worldwide. Early diagnosis is essential for cure, as 5 year cancer-specific survival is 90 - 100 % in patients with intraepithelial neoplasms and in those with low-grade superficial tumors without lymphovascular invasion, but it drops to 30% in men with multiple mobile or bilateral inguinal lymph nodes. The EGFR family plays a major role in penile cancer biology, with distinct receptors being involved in HPV-positive and -negative tumors. A number of anti-EGFR agents were used in penile cancer patients outside the context of a clinical trial, mainly as a salvage treatment after failure of first-line chemotherapy. A total of 28 patients received anti-EGFR monoclonal antibodies, with 50% of them showing a response to treatment, and a median PFS of ∼ 3 months. The rarity of the disease poses great challenge in terms of education and awareness of the general population, planning of preventive measures on a large scale, as well as conduction of prospective trials and approval of high-cost biological therapy. PMID:25496291

  18. Biological and life-history factors affecting total mercury concentrations in Arctic charr from Heintzelman Lake, Ellesmere Island, Nunavut

    Energy Technology Data Exchange (ETDEWEB)

    Velden, Shannon van der, E-mail: sdorn@sciborg.uwaterloo.ca [Department of Biology, University of Waterloo, Waterloo, Ontario, Canada N2L 3G1 (Canada); Reist, James D.; Babaluk, John A. [Freshwater Institute, Fisheries and Oceans Canada, Winnipeg, Manitoba, Canada R3T 2N6 (Canada); Power, Michael, E-mail: m3power@sciborg.uwaterloo.ca [Department of Biology, University of Waterloo, Waterloo, Ontario, Canada N2L 3G1 (Canada)

    2012-09-01

    A snapshot sample of Arctic charr (Salvelinus alpinus) from Heintzelman Lake (81 Degree-Sign 42 Prime N, 66 Degree-Sign 56 Prime W), Ellesmere Island, Canada was used to elucidate the biological and life-history factors potentially influencing individual total mercury (THg) concentrations. Migratory history was significant, with anadromous fish having a lower mean THg concentration (64 {mu}g/kg ww) than the non-anadromous Arctic charr (117 {mu}g/kg ww). The increase in individual THg concentration with age was shown to be independent of length-at-age when large and small individuals within the same age groups were compared. Similarly, the diets of individual Arctic charr were comparable regardless of size, and there was no apparent ontogenetic shift in diet that could explain differences in length-at-age or THg concentration among fast- and slow-growing groups of fish (i.e., fish of the same age but differing sizes). Maturity state was also not related to THg concentration, but appears to be related to differences in length-at-age, with slow-growing fish allocating more energy to reproduction than fast-growing conspecifics. The differences in THg concentration among individual Arctic charr were best explained by fish age. We suggest that the increase in mercury concentration with age can be altered by a shift in diet (e.g., to piscivory) or habitat (e.g., anadromy), but is otherwise unaffected by changes in size or length-at-age. -- Highlights: Black-Right-Pointing-Pointer Total mercury concentrations ([THg]) were measured in Arctic charr from a single lake in the Canadian high Arctic. Black-Right-Pointing-Pointer Anadromous Arctic charr had a significantly lower mean [THg] (64 {mu}g/kg ww) than the non-anadromous fish (117 {mu}g/kg ww). Black-Right-Pointing-Pointer Length-at-age (i.e., average somatic growth rate) was not related to mean [THg] when same-age groups were compared. Black-Right-Pointing-Pointer Prey resource use, determined by {delta}{sup 13}C and

  19. Biological and life-history factors affecting total mercury concentrations in Arctic charr from Heintzelman Lake, Ellesmere Island, Nunavut

    International Nuclear Information System (INIS)

    A snapshot sample of Arctic charr (Salvelinus alpinus) from Heintzelman Lake (81°42′N, 66°56′W), Ellesmere Island, Canada was used to elucidate the biological and life-history factors potentially influencing individual total mercury (THg) concentrations. Migratory history was significant, with anadromous fish having a lower mean THg concentration (64 μg/kg ww) than the non-anadromous Arctic charr (117 μg/kg ww). The increase in individual THg concentration with age was shown to be independent of length-at-age when large and small individuals within the same age groups were compared. Similarly, the diets of individual Arctic charr were comparable regardless of size, and there was no apparent ontogenetic shift in diet that could explain differences in length-at-age or THg concentration among fast- and slow-growing groups of fish (i.e., fish of the same age but differing sizes). Maturity state was also not related to THg concentration, but appears to be related to differences in length-at-age, with slow-growing fish allocating more energy to reproduction than fast-growing conspecifics. The differences in THg concentration among individual Arctic charr were best explained by fish age. We suggest that the increase in mercury concentration with age can be altered by a shift in diet (e.g., to piscivory) or habitat (e.g., anadromy), but is otherwise unaffected by changes in size or length-at-age. -- Highlights: ► Total mercury concentrations ([THg]) were measured in Arctic charr from a single lake in the Canadian high Arctic. ► Anadromous Arctic charr had a significantly lower mean [THg] (64 μg/kg ww) than the non-anadromous fish (117 μg/kg ww). ► Length-at-age (i.e., average somatic growth rate) was not related to mean [THg] when same-age groups were compared. ► Prey resource use, determined by δ13C and δ15N isotopes and gut contents, was similar among fast- and slow-growing fish. ► Maturity state was not related to [THg], but the slow-growing group

  20. Chemical and biological tracers to determine groundwater flow in karstic aquifer, Yucatan Peninsula

    Science.gov (United States)

    Lenczewski, M.; Leal-Bautista, R. M.; McLain, J. E.

    2013-05-01

    Little is known about the extent of pollution in groundwater in the Yucatan Peninsula; however current population growth, both from international tourism and Mexican nationals increases the potential for wastewater release of a vast array of contaminants including personal care products, pharmaceuticals (Rx), and pathogenic microorganisms. Pathogens and Rx in groundwater can persist and can be particularly acute in this region where high permeability of the karst bedrock and the lack of top soil permit the rapid transport of contaminants into groundwater aquifers. The objective of this research is to develop and utilize novel biological and chemical source tracking methods to distinguish between different sources of anthropogenic pollution in degraded groundwater. Although several methods have been used successfully to track fecal contamination sources in small scale studies, little is known about their spatial limitations, as source tracking studies rarely include sample collection over a wide geographical area and with different sources of water. In addition, although source tracking methods to distinguish human from animal fecal contamination are widely available, this work has developed source tracking distinguish between separate human populations is highly unique. To achieve this objective, we collected water samples from a series of drinking wells, cenotes (sinkholes), wastewater treatment plants, and injection wells across the Yucatan Peninsula and examine potential source tracers within the collected water samples. The result suggests that groundwater sources impacted by tourist vs. local populations contain different chemical stressors. This work has developed a more detailed understanding of the presence and persistence of personal care products, pharmaceuticals, and fecal indicators in a karstic system; such understanding will be a vital component for the protection Mexican groundwater and human health. Quantification of different pollution sources

  1. Ecological and biological determinants of trace elements accumulation in liver and kidney of Pontoporia blainvillei

    Energy Technology Data Exchange (ETDEWEB)

    Seixas, Tercia G. [Departamento de Quimica, PUC-Rio, 22453-900 Rio de Janeiro, RJ (Brazil); Laboratorio de Radioisotopos Eduardo Penna Franca, IBCCF-UFRJ, 21941-902 Rio de Janeiro, RJ (Brazil)], E-mail: tercia@rdc.puc-rio.br; Kehrig, Helena do A. [Laboratorio de Radioisotopos Eduardo Penna Franca, IBCCF-UFRJ, 21941-902 Rio de Janeiro, RJ (Brazil); Fillmann, Gilberto [Departamento de Oceanografia, FURG, 96201-900 Rio Grande, RS (Brazil); Di Beneditto, Ana Paula M.; Souza, Cristina M.M. [Laboratorio de Ciencias Ambientais, CBB-UENF, 28013-602 Campos dos Goytacazes, RJ (Brazil); Secchi, Eduardo R. [Departamento de Oceanografia, FURG, 96201-900 Rio Grande, RS (Brazil); Laboratorio de Tartarugas e Mamiferos Marinhos, Departamento de Oceonagrafia e Museu Oceanografico ' Prof. E.C. Rios' , FURG, 96201-900, Rio Grande, RS (Brazil); Moreira, Isabel [Departamento de Quimica, PUC-Rio, 22453-900 Rio de Janeiro, RJ (Brazil); Malm, Olaf [Laboratorio de Radioisotopos Eduardo Penna Franca, IBCCF-UFRJ, 21941-902 Rio de Janeiro, RJ (Brazil)

    2007-10-15

    The present work tested whether ecological and biological variables have an influence on the assimilation of trace elements by the tissues of a cetacean from the Western South Atlantic Ocean. No significant differences were observed in the concentrations for both sexes. As individuals from the two sampling areas belong to distinct genetic and morphological populations, animals of similar body length were older on the southeastern than on the southern coast. The liver showed the highest concentrations of mercury, whereas the highest levels of cadmium were found in the kidney. Hepatic mercury, cadmium and selenium in individuals from the south coast were about four times as high as those from the southeast coast. However, arsenic in the liver and kidney were similar in both coastal areas. Hepatic mercury, cadmium and selenium concentrations increased with body length in individuals from the southeastern coast, although no significant correlations (P > 0.05) were observed between body length from either area and the renal and hepatic As concentrations. A significant positive linear relationship was observed between molar concentrations of Hg and Se in the liver of all individuals from both areas (r{sup 2} = 0.93; P < 0.001), presenting Se:Hg ratios close to 4. Differences found among the concentrations of Hg, Cd and Se in dolphins from both areas were probably due to the preferred prey, bioavailability of elements in each marine environment, and environment variables (water temperature, net primary production). As a consequence, concentrations of trace elements in the tissues of this species can be considered to be a result of the surrounding environment.

  2. Biological identification and determination of optimum growth conditions for four species ofNavicula

    Institute of Scientific and Technical Information of China (English)

    ZHAO Xiaobo; PANG Shaojun; LIU Feng; SHAN Tifeng; LI Jing

    2014-01-01

    Four species in the genus Navicula were isolated using the serial dilution method. Based on scanning elec-tron microscopy (SEM) and sequence comparisons of two segments of genes (small ribosomal subunit and large subunit of Rubisco), the species were identified asNavicula perminuta,N. pseudacceptata,N. vara, andN. rhynchocephala. Based on phylogenetic analysis and culture trials,there was a close relationship betweenN. perminutaandN. vara. Growth of these species was evaluated using measurements of optical density at 680 nm (OD680) under various environmental factors. Results showed that the optimum culture conditions were 25°C, 50-100 μmol photons m-2 s-1, pH 8.0, and salinities from 25 to 30. However, the favor-able salinity forN. perminuta was surprisingly high at 35. Nutrient requirement analysis demonstrated that growth ofNavicula depended on the availability of SiO32-. Their relative growth rates (RGR) peaked at the highest tested level (0.25 mmol/L). The optimal concentrations of NO3-and PO43- were 3.6 mmol/L and 0.18 mmol/L, respectively. Culture of theseNavicula species for abalone or sea cucumber aquaculture should take these factors into consideration.

  3. Ion-pair assisted extraction followed by (1)H NMR determination of biogenic amines in food and biological matrices.

    Science.gov (United States)

    Chatzimitakos, T; Exarchou, V; Ordoudi, S A; Fiamegos, Y; Stalikas, C

    2016-07-01

    A selective method for the extraction and determination of six biogenic amines (BAs) by NMR is presented. Briefly, BAs are extracted into an organic solvent via the use of an ion pairing agent, followed by a back extraction in D2O in order to acquire the (1)H NMR spectra. The method is studied with respect to the critical experimental parameters and is successfully applied to selected food substrates (dark chocolate, banana, gouda cheese) and biological samples (urine and blood plasma) signifying its potential as an alternative tool for BAs determination. Accurate and precise results are consistently achieved with all matrixes studied. The calculated limits of detection and limits of quantitation were found to be in the ranges 0.05-0.13μg/mL and 0.14-0.38μg/mL, respectively, for biological samples while for food samples they were in the ranges 2.25-6.25μg/g and 6.75-18.7μg/g, respectively. PMID:26920317

  4. Determination of curcumin in biologically active supplements and food spices using a mesofluidic platform with fluorescence detection.

    Science.gov (United States)

    Petrova, Anastasiia; Dar'in, Dmitriy; Ivanov, Aleхander; Moskvin, Leonid; Ishimatsu, Ryoichi; Nakano, Koji; Imato, Toshihiko; Bulatov, Andrey

    2016-10-01

    A mesofluidic platform (MP) with fluorescence detection based on a stepwise injection analysis (SWIA) was used for the determination of curcumin in biologically active supplements and food spices. The main units of the MP are a mixing chamber (MC) and an optical channel with a quartz capillary inside. The MC provides rapid and complete mixing solutions by gas bubbling. The proposed method is based on the new rapid and sensitive reaction of curcumin with a fluorescence reagent - 4-(2,3,3-trimethyl-3H-indolium-1-yl)butane-1-sulfonate (TIBS). The fluorescence intensity of TIBS is greatly quenched in the presence of curcumin in an alkaline medium. The linear range was from 1 to 10µM of curcumin, and the limit of detection, calculated as 3σ of a blank test (n=5), was found to be 0.3µM. The sample throughput was 24h(-1). The proposed method was successfully applied for the determination of curcumin in biologically active supplements and samples of food spices. The obtained data were in good agreement with those measured by a HPLC-UV method.

  5. Determination of curcumin in biologically active supplements and food spices using a mesofluidic platform with fluorescence detection.

    Science.gov (United States)

    Petrova, Anastasiia; Dar'in, Dmitriy; Ivanov, Aleхander; Moskvin, Leonid; Ishimatsu, Ryoichi; Nakano, Koji; Imato, Toshihiko; Bulatov, Andrey

    2016-10-01

    A mesofluidic platform (MP) with fluorescence detection based on a stepwise injection analysis (SWIA) was used for the determination of curcumin in biologically active supplements and food spices. The main units of the MP are a mixing chamber (MC) and an optical channel with a quartz capillary inside. The MC provides rapid and complete mixing solutions by gas bubbling. The proposed method is based on the new rapid and sensitive reaction of curcumin with a fluorescence reagent - 4-(2,3,3-trimethyl-3H-indolium-1-yl)butane-1-sulfonate (TIBS). The fluorescence intensity of TIBS is greatly quenched in the presence of curcumin in an alkaline medium. The linear range was from 1 to 10µM of curcumin, and the limit of detection, calculated as 3σ of a blank test (n=5), was found to be 0.3µM. The sample throughput was 24h(-1). The proposed method was successfully applied for the determination of curcumin in biologically active supplements and samples of food spices. The obtained data were in good agreement with those measured by a HPLC-UV method. PMID:27474312

  6. Common Virulence Factors and Tissue Targets of Entomopathogenic Bacteria for Biological Control of Lepidopteran Pests

    Directory of Open Access Journals (Sweden)

    Anaïs Castagnola

    2014-01-01

    Full Text Available This review focuses on common insecticidal virulence factors from entomopathogenic bacteria with special emphasis on two insect pathogenic bacteria Photorhabdus (Proteobacteria: Enterobacteriaceae and Bacillus (Firmicutes: Bacillaceae. Insect pathogenic bacteria of diverse taxonomic groups and phylogenetic origin have been shown to have striking similarities in the virulence factors they produce. It has been suggested that the detection of phage elements surrounding toxin genes, horizontal and lateral gene transfer events, and plasmid shuffling occurrences may be some of the reasons that virulence factor genes have so many analogs throughout the bacterial kingdom. Comparison of virulence factors of Photorhabdus, and Bacillus, two bacteria with dissimilar life styles opens the possibility of re-examining newly discovered toxins for novel tissue targets. For example, nematodes residing in the hemolymph may release bacteria with virulence factors targeting neurons or neuromuscular junctions. The first section of this review focuses on toxins and their context in agriculture. The second describes the mode of action of toxins from common entomopathogens and the third draws comparisons between Gram positive and Gram negative bacteria. The fourth section reviews the implications of the nervous system in biocontrol.

  7. Microrespirometric determination of the effectiveness factor and biodegradation kinetics of aerobic granules degrading 4-chlorophenol as the sole carbon source.

    Science.gov (United States)

    Vital-Jacome, Miguel; Buitrón, Germán; Moreno-Andrade, Ivan; Garcia-Rea, Victor; Thalasso, Frederic

    2016-08-01

    In this study, a microrespirometric method was used, i.e., pulse respirometry in microreactors, to characterize mass transfer and biodegradation kinetics in aerobic granules. The experimental model was an aerobic granular sludge in a sequencing batch reactor (SBR) degrading synthetic wastewater containing 4-chlorophenol as the sole carbon source. After 15 days of acclimation, the SBR process degraded 4-chlorophenol at a removal rate of up to 0.9kg CODm(-3)d(-1), and the degradation kinetics were well described by the Haldane model. The microrespirometric method consisted of injecting pulses of 4-chlorophenol into the 24 wells of a microreactor system containing the SBR samples. From the respirograms obtained, the following five kinetic parameters were successfully determined during reactor operation: (i) Maximum specific oxygen uptake rate, (ii) substrate affinity constant, (iii) substrate inhibition constant, (iv) maximum specific growth rate, and (v) cell growth yield. Microrespirometry tests using granules and disaggregated granules allowed for the determination of apparent and intrinsic parameters, which in turn enabled the determination of the effectiveness factor of the granular sludge. It was concluded that this new high-throughput method has the potential to elucidate the complex biological and physicochemical processes of aerobic granular biosystems. PMID:27054670

  8. Factors Determining the Career Success of Doctorate Holders: Evidence from the Spanish Case

    Science.gov (United States)

    Canal-Domínguez, J. F.; Wall, Alan

    2014-01-01

    This paper analyses the determining factors of PhDs' career success. Earnings have been used as an objective measure, and a subjective measure of success was constructed based on the individuals' assessments of broader aspects of their job position. When analysing the data by field of knowledge and gender, it was found that males and PhD…

  9. Determinants of Business Student Satisfaction and Retention in Higher Education: Applying Herzberg's Two-Factor Theory

    Science.gov (United States)

    DeShields, Oscar W., Jr.; Kara, Ali; Kaynak, Erdener

    2005-01-01

    Purpose: This paper focuses on the determinants of student satisfaction and retention in a college or university that are assumed to impact students' college experience. Design/methodology/approach: Using empirical data and Herzberg's two-factor theory, a modified version of the questionnaire developed by Keaveney and Young was administered to…

  10. Risk factors and determinants of neurodevelopmental outcome in cystic periventricular leucomalacia

    NARCIS (Netherlands)

    Resch, B; Vollaard, E; Maurer, U; Haas, J; Rosegger, H; Muller, W

    2000-01-01

    The aim of the study was to determine risk factors for the development of cystic periventricular leucomalacia (PVL) and to correlate ultrasound findings with neurodevelopmental outcome. By means of a retrospective case-control study (matched for gestational age, birth weight, sex, and year of birth)

  11. Determination of tin equilibrium isotope fractionation factors from synchrotron radiation experiments

    NARCIS (Netherlands)

    Polyakov, VB; Mineev, SD; Clayton, RN; Hu, G; Mineev, KS

    2005-01-01

    A method of determination of the reduced isotopic partition function ratio (beta-factor) from the partial density of state (PDOS) obtained by inelastic nuclear resonant X-ray scattering (INRXS) in synchrotron radiation experiments has been established. The method has been demonstrated by the example

  12. Factors of Attrition in Cohort Doctoral Education: A Self-Determination Theory Perspective

    Science.gov (United States)

    Garcia, Linda Ann

    2013-01-01

    Attrition rates, completion rates, and time to degree are the key areas researchers have sought to examine influencing factors and patterns of behavior that describe the departure process of students in doctoral study. Through the lens of self-determination theory (Deci & Ryan, 1985), the purpose of this phenomenological qualitative study was…

  13. The Human Factor in the Acceptance of OER. What determines readiness to share?

    NARCIS (Netherlands)

    Rubens, Wilfred; Didderen, Wim

    2013-01-01

    Rubens, W., & Didderen, W. (2013). The Human Factor in the Acceptance of OER. What determines readiness to share? In R. Jacobi, H. Jelgerhuis, & N. van der Woert (Eds.), Trendreport Open Educational Resources 2013 (pp. 84-88). Utrecht: SURF Foundation - Special Interest Group Open Educational Resour

  14. An experimental method to determine the electrostatic field enhancement factor of a practical conductor surface

    DEFF Research Database (Denmark)

    McAllister, Iain Wilson; Crichton, George C

    1989-01-01

    A method of determining the field enhancement factor of a practical conductor is presented. The method is developed from a modified theory of discharge onset in a gaseous medium. This modification incorporates the influence of conductor surface roughness. Onset data from an experimental study tha...

  15. DETERMINATION OF RATIONAL KINEMATIC DISCREPANCY FACTOR AND DIAGRAMS OF WHEEL TRACTOR DRIVE AXLE GEAR

    Directory of Open Access Journals (Sweden)

    A. V. Gouskov

    2008-01-01

    Full Text Available Accepting a traction efficiency as a criterion of effectiveness an optimum kinematic discrepancy factor  for a 4К4-model tractor with identical or different wheels and also schemes of drive axle gears are determined in the paper.

  16. Biophysical and human factors determine the distribution of poached elephants in Tsavo East National Park, Kenya

    NARCIS (Netherlands)

    Kyale, D.M.; Ngene, S.M.; Maingi, J.

    2011-01-01

    This study investigates the distribution of poached elephants as well as the biophysical and anthropogenic factors that determine the distribution of the poached elephants in Tsavo East National Park (TENP), Kenya. Data on the distribution of poached elephants, from 1990 to 2005, were acquired from

  17. Agri-Environmental Resource Management by Large-Scale Collective Action: Determining KEY Success Factors

    Science.gov (United States)

    Uetake, Tetsuya

    2015-01-01

    Purpose: Large-scale collective action is necessary when managing agricultural natural resources such as biodiversity and water quality. This paper determines the key factors to the success of such action. Design/Methodology/Approach: This paper analyses four large-scale collective actions used to manage agri-environmental resources in Canada and…

  18. Polymer monolithic capillary microextraction on-line coupled with inductively coupled plasma-mass spectrometry for the determination of trace Au and Pd in biological samples

    International Nuclear Information System (INIS)

    A novel method based on on-line polymer monolithic capillary microextraction (CME)-inductively coupled plasma mass spectrometry (ICP-MS) was developed for the determination of trace Au and Pd in biological samples. For this purpose, poly(glycidyl methacrylate-ethylene dimethacrylate) monolith was prepared and functionalized with mercapto groups. The prepared monolith exhibited good selectivity to Au and Pd, and good resistance to strong acid with a long life span. Factors affecting the extraction efficiency of CME, such as sample acidity, sample flow rate, eluent conditions and coexisting ion interference were investigated in detail. Under the optimal conditions, the limits of detection (LODs, 3σ) were 5.9 ng L−1 for Au and 8.3 ng L−1 for Pd, and the relative standard deviations (RSDs, c = 50 ng L−1, n = 7) were 6.5% for Au and 1.1% for Pd, respectively. The developed method was successfully applied to the determination of Au and Pd in human urine and serum samples with the recovery in the range of 84–118% for spiked samples. The developed on-line polymer monolithic CME-ICP-MS method has the advantages of rapidity, simplicity, low sample/reagent consumption, high sensitivity and is suitable for the determination of trace Au and Pd in biological samples with limited amount available and complex matrix. - Highlights: • An on-line CME-ICP-MS method was developed for Au and Pd analysis in human fluids. • Poly(GMA-EDMA-SH) monolith exhibited good selectivity for Au/Pd and acid-resistance. • The method is rapid, simple, and sensitive with low sample/reagents consumption

  19. Determination of copper, molybdenum and selenium in biological reference materials by inductively coupled plasma mass spectrometry

    International Nuclear Information System (INIS)

    In a contribution to the elemental characterization of 10 new reference materials, Bovine Muscle Powder (136), Corn Starch (162), Hard Red Spring Wheat Flour (165), Soft Winter Wheat Flour (166), Whole Milk Powder (183), Wheat Gluten (184), Corn Bran (186). Durum Wheat Flour (187), Whole Egg Powder (188) and Microcrystalline Cellulose (189), the total concentrations of Cu, Mo and Se were determined by the application of an analytical method based on isotope dilution inductively coupled plasma mass spectrometry. Cu and Mo contents were quantified by measurement of 65Cu/63Cu and 97Mo/100Mo isotopic ratios following spiking with 65Cu and 97Mo and digestion with nitric acid. Selenium was separated as hydrogen selenide from the matrix using sodium borohydride after spiking with 82Se and acid digestion-dry ashing and quantified by measurement of the 82Se/78Se isotopic ratio. Comparison of these results with those from a variety of other methods and assessment of the procedures using certified reference materials indicated that the determinations of Cu, Mo and Se were performed without analytical bias. (orig.)

  20. Determination of biological activity from fluorescence-lifetime measurements in Saccharomyces cerevisiae

    Science.gov (United States)

    Rudek, F.; Baselt, T.; Lempe, B.; Taudt, C.; Hartmann, P.

    2015-03-01

    The importance of fluorescence lifetime measurement as an optical analysis tool is growing. Many applications already exist in order to determine the fluorescence lifetime, but the majority of these require the addition of fluorescence-active substances to enable measurements. Every usage of such foreign materials has an associated risk. This paper investigates the use of auto-fluorescing substances in Saccharomyces cerevisiae (Baker's yeast) as a risk free alternative to fluorescence-active substance enabled measurements. The experimental setup uses a nitrogen laser with a pulse length of 350 ps and a wavelength of 337 nm. The excited sample emits light due to fluorescence of NADH/NADPH and collagen. A fast photodiode collects the light at the output of an appropriate high-pass edge-filter at 400 nm. Fluorescence lifetimes can be determined from the decay of the measurement signals, which in turn characterizes the individual materials and their surrounding environment. Information about the quantity of the fluorescence active substances can also be measured based on the received signal intensity. The correlation between the fluorescence lifetime and the metabolic state of Saccharomyces cerevisiae was investigated and is presented here.

  1. Magnetosomes as biological model for iron binding: relaxivity determination with MRI

    International Nuclear Information System (INIS)

    Purpose: In vitro characterization of iron-containing bacterial particles (magnetosomes) as superparamagnetic contrast agents for MRI. Material and Methods: Different concentrations of magnetosomes were examined with a 1.5 T clinical whole-body MR system at 21 C using the transit/receive extremity coil. Both longitudinal and transversal relaxivities (R1 and R2) of the magnetosomes were determined by an inversion recovery snapshot gradient recall echo (IR FLASH) with various inversion times and a multi echo spin echo sequence. Atomic absorption spectrometry (AAS) and electron microscopy were used as reference standard. Results: Longitudinal and transverse relaxivities of the magnetosomes were calculated to be R1=7.688 mmol-1 s-1 and R2=147.67 mmol-1 s-1, respectively. The corresponding iron concentrations were determined in all dilutions using AAS, while the magnetosomes were morphologically delineated by electron microscopy. Conclusion: Magnetosomes represent a new and interesting class of iron-containing contrast agents warranting further evaluation in cellular cultures and animal models. Magnetosomes may be suited for displaying the vector distribution and gene expression of new molecular therapies. (orig.)

  2. Determining the Chemical and Biological Availability of Zinc in Urban Stormwater Retention Ponds

    Science.gov (United States)

    Camponelli, K.; Casey, R.; Lev, S. M.; Landa, E. R.; Snodgrass, J.

    2005-12-01

    Highway runoff has the potential to negatively impact receiving systems due to transport of contaminants that accumulate on road surfaces. Metals such as copper and zinc are major components of automobile brake pads and tires, respectively. As these automobile parts are degraded, these metal containing particulates are deposited on the roadway and are washed into storm water retention ponds and surface water bodies during precipitation events. It has been estimated that 15 to 60% of the Zn in urban stormwater runoff comes from tire wear and that tire wear is a significant source of Zn to the environment with release inventories comparable to waste incineration sources. In urban and sub-urban systems, this large source of Zn can accumulate in stormwater retention ponds which serve as habitat for a variety of species. Understanding the chemical and biological availability of Zn to biota is integral to assessing the habitat quality of retention ponds. This study is a first effort to relate the amount and speciation of Zn in a retention pond to Zn inputs through highway-derived runoff events. In addition, results suggest that the chemical speciation and availability of particulate Zn can be related to the bioavailability and toxicity of Zn to pond organisms (i.e. larval amphibians). The study site in Owings Mills, MD is located next to a four-lane highway from which it receives runoff through a single culvert. Five species of anurans are known to utilize the pond as a breeding site and Zn in amphibian tissues and retention pond sediments were highly elevated at this site in 2001 and 2002. A recent analysis of pond sediments, soils, roadway dust and storm water collected at this site suggests that roadway particulate matter transported during runoff events is the dominant source of Zn in this system. Overall, Zn and other trace metals were found to be most abundant in the clay sized faction of pond sediments and soils. The pond cores were found to have higher Zn and Cu

  3. Method for determining correction factors induced by irradiation of ionization chamber cables in large radiation field

    International Nuclear Information System (INIS)

    A simple method was developed to be suggested to hospital physicists in order to be followed during large radiation field dosimetry, to evaluate the effects of cables, connectors and extension cables irradiation and to determine correction factors for each system or geometry. All quality control tests were performed according to the International Electrotechnical Commission for three clinical dosimeters. Photon and electron irradiation effects for cables, connectors and extention cables were investigated under different experimental conditions by means of measurements of chamber sensitivity to a standard radiation source of 90Sr. The radiation induced leakage current was also measured for cables, connectors and extension cables irradiated by photons and electrons. All measurements were performed at standard dosimetry conditions. Finally, measurements were performed in large fields. Cable factors and leakage factors were determined by the relation between chamber responses for irradiated and unirradiated cables. (author)

  4. Scale Factor Determination of Micro-Machined Angular Rate Sensors Without a Turntable

    Institute of Scientific and Technical Information of China (English)

    Gaisser Alexander; GAO Zhongyu; ZHOU Bin; ZHANG Rong; CHEN Zhiyong

    2006-01-01

    This paper presents a digital readout system to detect small capacitive signals of a micro-machined angular rate sensor. The flexible parameter adjustment ability and the computation speed of the digital signal processor were used to develop a new calibration procedure to determine the scale factor of a gyroscope without a turntable. The force of gravity was used to deflect the movable masses in the sensor, which resulted in a corresponding angular rate input. The gyroscope scale factor was then measured without a turntable. Test results show a maximum deviation of about 1.2% with respect to the scale factor determined on a turntable with the accuracy independent of the manufacturing process and property variations. The calibration method in combination with the improved readout electronics can minimize the calibration procedure and, thus, reduce the manufacturing costs.

  5. Affects as central organising and integrating factors. A new psychosocial/biological model of the psyche.

    Science.gov (United States)

    Ciompi, L

    1991-07-01

    A new psychosocial/biological model of the psyche is proposed, in which the affects play a central role in organising and integrating cognition. The psyche is understood here as a complex hierarchical structure of affective/cognitive systems of reference (or 'programmes for feeling, thinking, and behaviour'), generated by repetitive concrete action. These systems store past experience in their structure, and provide the functional basis for further cognition and communication. Affects endow these programmes with a specific qualitative value (such as motivation), connect cognitive elements synchronically and diachronically, and contribute to their storage and mobilisation according to context. They also participate in differentiating cognitive systems at higher levels of abstraction. These assumptions are supported by recent findings on the role of the limbic and hypothalamic system for the regulation of emotion, on neuronal plasticity, and on the phenomenon of state-dependent learning and memory. Refutable hypotheses are formulated for further research on the interaction of emotion and cognition.

  6. Posttranscriptional Regulation of Splicing Factor SRSF1 and Its Role in Cancer Cell Biology

    Directory of Open Access Journals (Sweden)

    Vânia Gonçalves

    2015-01-01

    Full Text Available Over the past decade, alternative splicing has been progressively recognized as a major mechanism regulating gene expression patterns in different tissues and disease states through the generation of multiple mRNAs from the same gene transcript. This process requires the joining of selected exons or usage of different pairs of splice sites and is regulated by gene-specific combinations of RNA-binding proteins. One archetypical splicing regulator is SRSF1, for which we review the molecular mechanisms and posttranscriptional modifications involved in its life cycle. These include alternative splicing of SRSF1 itself, regulatory protein phosphorylation events, and the role of nuclear versus cytoplasmic SRSF1 localization. In addition, we resume current knowledge on deregulated SRSF1 expression in tumors and describe SRSF1-regulated alternative transcripts with functional consequences for cancer cell biology at different stages of tumor development.

  7. Correction factor for real-time determination of wood dust mass concentration by photometric method

    Directory of Open Access Journals (Sweden)

    Ankica Čavlović

    2009-03-01

    Full Text Available Samples of wood dust were collected in the working environment of wood machining processes for the purpose of determining correction factors for measuring mass concentration of wood dust by photometric method. According to the NIOSH 0600 Norm and NIOSH Manual of Analytical Methods for photometric measurement, correction factor must be determined before measuring mass concentration of different types of dust. The correction factor is defined as the ratio of mass concentration obtained by the gravimetric method and mass concentration obtained by the photometric method. The correction factor should be determined because of the influence of particle size distribution, density, particle shape and refractive index on values obtained by the photometric method. The aim of the research was to investigate the possibility of using photometric method for the determination of mass concentration of inhalable fraction of airborne wood dust. Sampling was conducted in several woodworking plants during the machining of wet and dry beech-wood, wet and dry oak-wood, wet fir-wood and particleboard. There is a significant correlation between the results obtained by the photometric method and values obtained by the gravimetric method (R2=0.88 and this is the base for using the photometric method in determining mass concentration of airborne wood dust. According to the results of this research, correction factors must be determined and used for measuring mass concentration of inhalable wood dust during the machining of different wood species and wood with different moisture content. The best corresponding results of photometric and gravimetric methods are obtained for the samples collected during machining of wet fir-wood (k=1. The largest correction factor should be used in determining workers exposure to wood dust during machining of dry oak-wood (k=4.4 and particleboard (k=4.5. Only the results of 8-hour measurements of mass concentration by gravimetric methods can

  8. Peptic Ulcer at the End of the 20th Century: Biological and Psychological Risk Factors

    Directory of Open Access Journals (Sweden)

    Susan Levenstein

    1999-01-01

    Full Text Available The prevailing concept of peptic ulcer etiology has swung over entirely in just a few years from the psychological to the infectious, yet the rich literature documenting an association between psychosocial factors and ulcer is not invalidated by the discovery of Helicobacter pylori. Physical and psychological stressors interact to induce ulcers in animal models, concrete life difficulties and subjective distress predict the development of ulcers in prospective cohorts, shared catastrophes such as war and earthquakes lead to surges in hospitalizations for complicated ulcers, and stress or anxiety can worsen ulcer course. Many known ulcer risk factors, including smoking, nonsteroidal anti-inflammatory drug use, heavy drinking, loss of sleep and skipping breakfast, can increase under stress; the association of low socioeconomic status with ulcer is also accounted for in part by psychosocial factors. Among possible physiological mechanisms, stress may induce gastric hypersecretion, reduce acid buffering in the stomach and the duodenum, impair gastroduodenal blood flow, and affect healing or inflammation through psychoneuroimmunological mechanisms. Psychosocial factors seem to be particularly prominent among idiopathic or complicated ulcers, but they are probably operative in run of the mill H pylori disease as well, either through additive effects or by facilitating the spread of the organism across the pylorus, while gastrointestinal damage by nonsteroidal anti-inflammatory drugs can also be potentiated by stress. Although the clinical importance of peptic ulcer is fading along with the millenium, due to secular trends and new therapies, it remains worthy of study as a splendid example of the biopsychosocial model.

  9. Mathematical methods of factorization and a feedback approach for biological systems

    CERN Document Server

    Cornejo-Perez, O

    2005-01-01

    The first part of the thesis is devoted to factorizations of linear and nonlinear differential equations leading to solutions of the kink type. The second part contains a study of the synchronization of the chaotic dynamics of two Hodgkin-Huxley neurons by means of the mathematical tools belonging to the geometrical control theory.

  10. Structural Biology of Tumor Necrosis Factor Demonstrated for Undergraduates Instruction by Computer Simulation

    Science.gov (United States)

    Roy, Urmi

    2016-01-01

    This work presents a three-dimensional (3D) modeling exercise for undergraduate students in chemistry and health sciences disciplines, focusing on a protein-group linked to immune system regulation. Specifically, the exercise involves molecular modeling and structural analysis of tumor necrosis factor (TNF) proteins, both wild type and mutant. The…

  11. Determination of the antiepileptics vigabatrin and gabapentin in dosage forms and biological fluids using Hantzsch reaction.

    Science.gov (United States)

    al-Zehouri, J; al-Madi, S; Belal, F

    2001-02-01

    A selective and sensitive method was developed for the determination of the anticonvulsants vigabatrin (I) (CAS 60643-86-9) and gabapentin (II) (CAS 60142-96-3). The method is based on the condensation of the drugs through their amino groups with acetylacetone and formaldehyde according to Hantzsch reaction yeilding the highly fluorescent dihydropyridine derivatives. The yellowish-orange color was also measured spectrophotometrically at 410 nm and 415 nm for I and II, respectively. The absorbance-concentration plots were rectilinear over the ranges 10-70 micrograms/ml and 20-140 micrograms/ml for I and II, respectively. As for the fluorescence-concentration plots, they were linear over the ranges 0.5-10 micrograms/ml and 2.5-20 micrograms/ml with minimum detection limits (S/N = 2) of 0.05 microgram/ml (approximately 2.1 x 10(-8) mol/l) and 0.1 microgram/ml (approximately 5.8 x 10(-7) mol/l) for I and II, respectively. The spectrophotometric method was applied to the determination of I and II in their tablets. The percentage recoveries +/- SD (n = 6) were 99.45 +/- 0.13 and 98.05 +/- 0.53, respectively. The spectrofluorimetric method was successfully applied to the determination of I and II in spiked human urine and plasma. The % recoveries +/- SD (n = 5) were 98.77 +/- 0.29 and 98.39 +/- 0.53 for urine and 99.32 +/- 0.74 and 98.90 +/- 0.96 for plasma, for I and II, respectively. No interference was encountered with the co-administered drugs: valproic acid (CAS 99-66-1), diphenylhydantoin (CAS 57-41-0), phenobarbital (CAS 50-06-6), carbamazepine (CAS 298-46-4), clonazepam (CAS 1622-61-3), clobazam (CAS 22316-47-8) or cimetidine (CAS 51481-61-9). A proposal of the reaction pathway is suggested. The advantages of the proposed methods over existing method are discussed. PMID:11258050

  12. 222 Rn determination and physicochemical characteristic and biological in aquifers in the Toluca Valley

    International Nuclear Information System (INIS)

    Concentration levels of 222 Rn and 226 Rn have been analyzed in water samples from boreholes belonging to the drinking water supply system around Toluca, Mexico. The 222 Rn source is the decay of 226 Rn within the solid matrix of the aquifer. The study was performed during the dry and rainy seasons. 222 Rn concentration was determined by the liquid scintillation technique, 226 Rn was determined by gamma spectrometry, the physicochemical parameters and bacteriological analysis were performed by conventional chemical techniques. Solubilized trace elements were determined by Inductively Coupled Plasma - Mass Spectrometry (Icp-Ms). The radon level fluctuations at the boreholes in Toluca city and Almoloya spring indicated differences in the radon content. At borehole Lodos Prietos 2, the temperature and radon level were systematically the highest in comparison with the other boreholes and the spring indicating a contribution of a regional flow to the water of this particular borehole. The result for 226 Rn, the average 222 Rn observed during the sampling period, no correspondence occurs between the radium and the radon content indicating that, radon is not supported by radium, but is incorporated into the water through fissures in the rocks in contact with the water. The radon levels obtained in house faucets which water is supplied by boreholes decrease as a function of the distance from the source borehole to the house. With the chemical composition of each one of the studied boreholes and spring a Piper diagram was draw indicating the kind of water. The boreholes and spring can be classified as bicarbonate calcium/magnesium. Almost no fluctuation on time was observed in the chemical species and trace elements only a slight increase was observed at the end of the rain season. At Almoloya, spring pollution with coliform bacteria and nitrates showed an anthropogenic contribution to the water deterioration probable and fertilizers and detritus. Most of the studied water

  13. TU-F-BRE-05: Experimental Determination of K Factor in Small Field Dosimetry

    International Nuclear Information System (INIS)

    Purpose: Small-field dosimetry is challenging due to charged-particle disequilibrium, source occlusion and more importantly finite size of detectors. IAEA/AAPM has published approach to convert detector readings to dose by k factor. Manufacturers have been trying to provide various types of micro-detectors that could be used in small fields. However k factors depends on detector perturbations and are derived using Monte Carlo simulation. PTW has introduced a microDiamond for small-field dosimetry. An experimental approach is presented to derive the k factor for this detector. Methods: PTW microDiamond is a small volume detector with 1.1 mm radius and 1.0 micron thick synthetic diamond. Output factors were measured from 1×1cm2 to 12×12 cm2 on a Varian machine at various depths using various micro-detectors with published k factors. Dose is calculated as reading * K. Assuming k factor is accurate, output factor should be identical with every micro-detectors. Hence published k values (Francescon et al Med Phys 35, 504-513,2008) were used to covert readings and then output factors were computed. Based on the converged curve from other detectors, k factor for microDiamond was computed versus field size. Results: Traditional output factors as ratio of readings normalized to 10×10 cm2 differ significantly for micro-detectors for fields smaller than 3×3 cm2 which are now being used extensively. When readings are converted to dose, the output factor is independent of detector. Based on this method, k factor for microDiamond was estimated to be nearly constant 0.993±0.007 over varied field sizes. Conclusion: Our method provides a unique opportunity to determine the k factor for any unknown detector. It is shown that even though k factor depends on machine type due to focal spot, however for fields ≥1×1 cm2 this method provides accurate evaluation of k factor. Additionally microDiamond could be used with assumption that k factor is nearly unity

  14. Synthesis and determination of some biological activities of novel 2,4-dinitrophenyl derivatives.

    Science.gov (United States)

    Öztürk Sarikaya, Sevim B; Kaya, Afşin A; Kaya, Elif Çelenk; Şentürk, Murat

    2015-03-01

    The antioxidant and radical scavenging activities of the synthesized compounds 3, 5, and 6 were determined by various in vitro assays such as 2,2-azino-bis(3-ethylbenzthiazoline-6-sulfonic acid radical (ABTS(·+) ) scavenging, ferric ion (Fe(3+) ) reducing power and ferrous ion (Fe(2+) ) chelating activities. Moreover, these activities were compared to those of standard antioxidants such as butylated hydroxyanisole, butylated hydroxytoluene, and trolox. The results showed that the new compounds (3, 5, and 6) had potential antioxidant activity. Besides, inhibition of the two human cytosolic carbonic anhydrase (hCA, EC 4.2.1.1) isozymes I and II with some nitrobenzene compounds was investigated. Compounds 1-6 showed Ki values in the range of 4.88-193.4 µM and 5.295-54.75 µM for hCA I and hCA II, respectively. PMID:25644396

  15. Sample preparation of biological macromolecular assemblies for the determination of high-resolution structures by cryo-electron microscopy.

    Science.gov (United States)

    Stark, Holger; Chari, Ashwin

    2016-02-01

    Single particle cryo-EM has recently developed into a powerful tool to determine the 3D structure of macromolecular complexes at near-atomic resolution, which allows structural biologists to build atomic models of proteins. All technical aspects of cryo-EM technology have been considerably improved over the last two decades, including electron microscopic hardware, image processing software and the ever growing speed of computers. This leads to a more widespread use of the technique, and it can be anticipated that further automation of electron microscopes and image processing tools will soon fully shift the focus away from the technological aspects, onto biological questions that can be answered. In single particle cryo-EM, no crystals of a macromolecule are required. In contrast to X-ray crystallography, this significantly facilitates structure determination by cryo-EM. Nevertheless, a relatively high level of biochemical control is still essential to obtain high-resolution structures by cryo-EM, and it can be anticipated that the success of the cryo-EM technology goes hand in hand with further developments of sample purification and preparation techniques. This will allow routine high-resolution structure determination of the many macromolecular complexes of the cell that until now represent evasive targets for X-ray crystallographers. Here we discuss the various biochemical tools that are currently available and the existing sample purification and preparation techniques for cryo-EM grid preparation that are needed to obtain high-resolution images for structure determination. PMID:26671943

  16. Mixed hemimicelles solid-phase extraction based on sodium dodecyl sulfate (SDS)-coated nano-magnets for the spectrophotometric determination of Fingolomid in biological fluids

    Science.gov (United States)

    Azari, Zhila; Pourbasheer, Eslam; Beheshti, Abolghasem

    2016-01-01

    In this study, mixed hemimicelles solid-phase extraction (SPE) based on sodium dodecyl sulfate (SDS)-coated nano-magnets Fe3O4 was investigated as a novel method for the separation and determination of Fingolimod (FLM) in water, urine and plasma samples prior to spectrophotometeric determination. Due to the high surface area of these new sorbents and the excellent adsorption capacity after surface modification by SDS, satisfactory extraction recoveries can be produced. The main factors affecting the adsolubilization of analysts, such as pH, surfactant and adsorbent amounts, ionic strength, extraction time and desorption conditions were studied and optimized. Under the selected conditions, FLM has been quantitatively extracted. The accuracy of the method was evaluated by recovery measurements on spiked samples, and good recoveries of 96%, 95% and 88% were observed for water, urine and plasma respectively. Proper linear behaviors over the investigated concentration ranges of 2-26, 2-17 and 2-13 mg/L with good coefficients of determination, 0.998, 0.997 and 0.995 were achieved for water, urine and plasma samples, respectively. To the best of our knowledge, this is the first time that a mixed hemimicelles SPE method based on magnetic separation and nanoparticles has been used as a simple and sensitive method for monitoring of FLM in water and biological samples.

  17. Determination of ultra trace amounts of bismuth in biological and water samples by electrothermal atomic absorption spectrometry (ET-AAS) after cloud point extraction

    Energy Technology Data Exchange (ETDEWEB)

    Shemirani, Farzaneh; Baghdadi, Majid; Ramezani, Majid; Jamali, Mohammad Reza

    2005-04-04

    A new approach for a cloud point extraction electrothermal atomic absorption spectrometric method was used for determining bismuth. The aqueous analyte was acidified with sulfuric acid (pH 3.0-3.5). Triton X-114 was added as a surfactant and dithizone was used as a complexing agent. After phase separation at 50 deg. C based on the cloud point separation of the mixture, the surfactant-rich phase was diluted using tetrahydrofuran (THF). Twenty microliters of the enriched solution and 10 {mu}l of 0.1% (w/v) Pd(NO{sub 3}){sub 2} as chemical modifier were dispersed into the graphite tube and the analyte determined by electrothermal atomic absorption spectrometry. After optimizing extraction conditions and instrumental parameters, a preconcentration factor of 196 was obtained for a sample of only 10 ml. The detection limit was 0.02 ng ml{sup -1} and the analytical curve was linear for the concentration range of 0.04-0.60 ng ml{sup -1}. Relative standard deviations were <5%. The method was successfully applied for the extraction and determination of bismuth in tap water and biological samples (urine and hair)

  18. Microbiological study of bacteriophage induction in the presence of chemical stress factors in enhanced biological phosphorus removal (EBPR).

    Science.gov (United States)

    Motlagh, Amir Mohaghegh; Bhattacharjee, Ananda S; Goel, Ramesh

    2015-09-15

    Polyphosphate accumulating organisms (PAOs) are responsible for carrying the enhanced biological phosphorus removal (EBPR). Although the EBPR process is well studied, the failure of EBPR performance at both laboratory and full-scale plants has revealed a lack of knowledge about the ecological and microbiological aspects of EBPR processes. Bacteriophages are viruses that infect bacteria as their sole host. Bacteriophage infection of polyphosphate accumulating organisms (PAOs) has not been considered as a main contributor to biological phosphorus removal upsets. This study examined the effects of different stress factors on the dynamics of bacteriophages and the corresponding effects on the phosphorus removal performance in a lab-scale EBPR system. The results showed that copper (heavy metal), cyanide (toxic chemical), and ciprofloxacin (antibiotic), as three different anthropogenic stress factors, can induce phages integrated onto bacterial genomes (i.e. prophages) in an enriched EBPR sequencing batch reactor, resulting in a decrease in the polyphosphate kinase gene ppk1 clades copy number, phosphorus accumulation capacity, and phosphorus removal performance. This study opens opportunities for further research on the effects of bacteriophages in nutrient cycles both in controlled systems such as wastewater treatment plants and natural ecosystems. PMID:26024959

  19. Ecosystems Biology Approaches To Determine Key Fitness Traits of Soil Microorganisms

    Science.gov (United States)

    Brodie, E.; Zhalnina, K.; Karaoz, U.; Cho, H.; Nuccio, E. E.; Shi, S.; Lipton, M. S.; Zhou, J.; Pett-Ridge, J.; Northen, T.; Firestone, M.

    2014-12-01

    The application of theoretical approaches such as trait-based modeling represent powerful tools to explain and perhaps predict complex patterns in microbial distribution and function across environmental gradients in space and time. These models are mostly deterministic and where available are built upon a detailed understanding of microbial physiology and response to environmental factors. However as most soil microorganisms have not been cultivated, for the majority our understanding is limited to insights from environmental 'omic information. Information gleaned from 'omic studies of complex systems should be regarded as providing hypotheses, and these hypotheses should be tested under controlled laboratory conditions if they are to be propagated into deterministic models. In a semi-arid Mediterranean grassland system we are attempting to dissect microbial communities into functional guilds with defined physiological traits and are using a range of 'omics approaches to characterize their metabolic potential and niche preference. Initially, two physiologically relevant time points (peak plant activity and prior to wet-up) were sampled and metagenomes sequenced deeply (600-900 Gbp). Following assembly, differential coverage and nucleotide frequency binning were carried out to yield draft genomes. In addition, using a range of cultivation media we have isolated a broad range of bacteria representing abundant bacterial genotypes and with genome sequences of almost 40 isolates are testing genomic predictions regarding growth rate, temperature and substrate utilization in vitro. This presentation will discuss the opportunities and challenges in parameterizing microbial functional guilds from environmental 'omic information for use in trait-based models.

  20. Two-photon excited fluorescent chemosensor for homogeneous determination of copper(II) in aqueous media and complicated biological matrix.

    Science.gov (United States)

    Liu, Lingzhi; Dong, Xiaohu; Xiao, Yan; Lian, Wenlong; Liu, Zhihong

    2011-05-21

    In the present work, a two-photon excited fluorescent chemosensor for Cu(2+) was prepared. The probe was constructed on the basis of internal charge transfer (ICT) principle with macrocyclic dioxotetraamine as the Cu(2+) receptor. The good water-solubility of the molecule enabled recognition and assay of Cu(2+) ions in biological media. The photophysical properties of the chemosensor were investigated in detail, exhibiting favorable fluorescence quantum yield and moderate two-photon absorption cross-section. The studies on binding thermodynamics demonstrated the formation of 1 : 1 complex between the chemosensor and Cu(2+) and an association constant of ca. 1.04 × 10(5) M(-1). Due to the rational design of the molecular structure, the sensor was highly specific to Cu(2+), which ensured high selectivity in Cu(2+) determination. Upon Cu(2+) binding, the intramolecular charge-transfer extent within the chromophore was weakened resulting in a remarkable quenching of fluorescence, based on which quantitative determination of Cu(2+) was performed. Good linearity was obtained between the fluorescence quenching value and Cu(2+) concentration ranging from 0.04 to 2.0 μM in aqueous solution. Benefiting from the merits of two-photon excitation, the chemosensor was free of interference from background luminescence in serum. A homogeneous quantitative determination of Cu(2+) was achieved in the serum medium with a linear range of 0.04 to 2.0 μM. Considering the structural flexibility of the sensor, this work also opens up the possibility to construct other two-photon excited chemosensors for direct homogeneous assay of various molecules/ions in complicated biological sample matrices. PMID:21416097

  1. Surfactant-Assisted Nanodrop Spectrophotometer Determination of Iron(III) in a Single Drop of Food, Biological, and Environmental Samples

    Science.gov (United States)

    Sharma, A.; Tapadia, K.; Sahin, R.; Shrivas, K.

    2016-01-01

    A surfactant-assisted nanodrop spectrophotometric (NDS) method has been developed for the determination of the iron(III) content in single drops (1 μ L) of food, biological, and or environmental sample using disodium 1-nitroso-2-naphthol-3,6-sulfonate (Nitroso-R salt) as a complexing agent and Tween-80 as non-ionic surfactant at pH 4.0. This method is based on the formation of a complex between the Fe(III) present in a sample and the Nitroso-R-salt in the presence of a surfactant to form a green-colored Fe(III)-Nitroso-R salt complex, which can be measured using a NDS method at a λ max = 710 nm. This system was found to obey Beer's law at concentrations in the range of 50-5000 μ g/L with slope, intercept and correlation coefficient values of 0.683, 0.102, and 0.986, respectively. The molar absorptivity of the complex in terms of the Fe(III) content was determined to be 4.86 × 10 5 L· mol -1 · cm -1 . The detection limit and %RSD values of the method were found to be 17 × 10-3 mg/L and ±1.3706%, respectively. This newly developed method was successfully applied to the determination of the Fe(III) content in single drops of food, biological, and environmental samples, and the results were compared with those obtained by atomic absorption spectrometry.

  2. Clinical and biologic factors related to oral implant failure: a 2-year follow-up study.

    Science.gov (United States)

    Moheng, Patrick; Feryn, Jean-Marc

    2005-09-01

    The purpose of this study is to evaluate urinary biomarkers of bone formation and resorption as predictive factors for oral implant failure, and to contribute to the knowledge of factors related to oral implant failure. A total of 93 patients between 18 and 85 years old, with an indication of oral implant, were eligible in this 2-year prospective, open, and nonrandomized study. Patients who had bone graft before implantation or presented with prosthetic difficulties (implant-to-crown ratio coating. Serum osteocalcin, and urinary pyridinoline and deoxypyridinoline were measured, together with bone density at implant location. The primary endpoint (implant failure) was the implant removal (radiographic evidence of peri-implant bone loss and/or pockets). Factors related to implant failure were analyzed using multilevel logistic regression models to consider within-patient effects. Of the 93 patients included, 61% were female, and 16% were current smokers. A total of 266 oral implants were placed and analyzed, with a mean number of 3.1 implants by patient. Eleven and 15% of bone locations scored at D1 and D4, respectively, for the Misch bone density scoring. The majority of implants (72%) were placed more than 3 months after tooth extraction, using a Frialit-2 system in 73% of cases. The mean of osteocalcin was 17.3 (+/-9.4) ng/L; those of pyridinoline and deoxypyridinoline were 33.2 (+/-15.8) and 10.2 (+/-11.9) mmol per creatinine mmol, respectively. At one-year, 95.5% (95% confidence interval 92.5-97.5) of implants have not been removed. One year later, no further implant failed. In both univariate and multivariate analysis, osteocalcin, pyridinoline, and deoxypyridinoline were not significant predictive factors of oral implant failure. In multilevel logistic regression analysis, only tobacco consumption and single-tooth replacement or removable prosthesis were independent and significant predictive factors of oral implant failure. Serum osteocalcin, and urinary

  3. Studies on the Biological Effects of Ozone: 10. Release of Factors from Ozonated Human Platelets

    Directory of Open Access Journals (Sweden)

    G. Valacchi

    1999-01-01

    Full Text Available In a previous work we have shown that heparin, in the presence of ozone (O3, promotes a dose-dependent platelet aggregation, while after Ca2+ chelation with citrate, platelet aggregation is almost negligible. These results led us to think that aggregation may enhance the release of platelet components. We have here shown that indeed significantly higher amount of platelet-derived growth factor (PDGF, transforming growth factor β1 (TGF-β1 and interleukin-8(IL-8 are released in a dose-dependent manner after ozonation of heparinised platelet-rich plasma samples. These findings may explain the enhanced healing of torpid ulcers in patients with chronic limbischemia treated with O3 autohaemoteraphy (O3-AHT.

  4. Cosmetics alter biologically-based factors of beauty: evidence from facial contrast.

    Science.gov (United States)

    Jones, Alex L; Russell, Richard; Ward, Robert

    2015-01-01

    The use of cosmetics by women seems to consistently increase their attractiveness. What factors of attractiveness do cosmetics alter to achieve this? Facial contrast is a known cue to sexual dimorphism and youth, and cosmetics exaggerate sexual dimorphisms in facial contrast. Here, we demonstrate that the luminance contrast pattern of the eyes and eyebrows is consistently sexually dimorphic across a large sample of faces, with females possessing lower brow contrasts than males, and greater eye contrast than males. Red-green and yellow-blue color contrasts were not found to differ consistently between the sexes. We also show that women use cosmetics not only to exaggerate sexual dimorphisms of brow and eye contrasts, but also to increase contrasts that decline with age. These findings refine the notion of facial contrast, and demonstrate how cosmetics can increase attractiveness by manipulating factors of beauty associated with facial contrast. PMID:25725411

  5. Cosmetics alter biologically-based factors of beauty: evidence from facial contrast.

    Science.gov (United States)

    Jones, Alex L; Russell, Richard; Ward, Robert

    2015-02-28

    The use of cosmetics by women seems to consistently increase their attractiveness. What factors of attractiveness do cosmetics alter to achieve this? Facial contrast is a known cue to sexual dimorphism and youth, and cosmetics exaggerate sexual dimorphisms in facial contrast. Here, we demonstrate that the luminance contrast pattern of the eyes and eyebrows is consistently sexually dimorphic across a large sample of faces, with females possessing lower brow contrasts than males, and greater eye contrast than males. Red-green and yellow-blue color contrasts were not found to differ consistently between the sexes. We also show that women use cosmetics not only to exaggerate sexual dimorphisms of brow and eye contrasts, but also to increase contrasts that decline with age. These findings refine the notion of facial contrast, and demonstrate how cosmetics can increase attractiveness by manipulating factors of beauty associated with facial contrast.

  6. Exploring membrane-associated NAC transcription factors in Arabidopsis: implications for membrane biology in genome regulation

    OpenAIRE

    Kim, Sun-Young; Kim, Sang-Gyu; Kim, Youn-Sung; Seo, Pil Joon; Bae, Mikyoung; Yoon, Hye-Kyung; Park, Chung-Mo

    2006-01-01

    Controlled proteolytic cleavage of membrane-associated transcription factors (MTFs) is an intriguing activation strategy that ensures rapid transcriptional responses to incoming stimuli. Several MTFs are known to regulate diverse cellular functions in prokaryotes, yeast, and animals. In Arabidopsis, a few NAC MTFs mediate either cytokinin signaling during cell division or endoplasmic reticulum (ER) stress responses. Through genome-wide analysis, it was found that at least 13 members of the NA...

  7. Synthesis and Biological Evaluation of Manassantin Analogues for Hypoxia-Inducible Factor 1α Inhibition

    OpenAIRE

    Kwon, Do-Yeon; Lee, Hye Eun; Weitzel, Douglas H.; PARK, KYUNGHYE; Lee, Sun Hee; Lee, Chen-Ting; Stephenson, Tesia N.; Park, Hyeri; Fitzgerald, Michael C.; Chi, Jen-Tsan; Mook, Robert A.; Dewhirst, Mark W.; Lee, You Mie; Hong, Jiyong

    2015-01-01

    To cope with hypoxia, tumor cells have developed a number of adaptive mechanisms mediated by hypoxia-inducible factor 1 (HIF-1) to promote angiogenesis and cell survival. Due to significant roles of HIF-1 in the initiation, progression, metastasis, and resistance to treatment of most solid tumors, a considerable amount of effort has been made to identify HIF-1 inhibitors for treatment of cancer. Isolated from Saururus cernuus, manassantins A (1) and B (2) are potent inhibitors of HIF-1 activi...

  8. Parent education and biologic factors influence on cognition in sickle cell anemia

    OpenAIRE

    King, Allison A; Strouse, John J.; Rodeghier, Mark J.; Compas, Bruce E.; Casella, James F; McKinstry, Robert C.; Noetzel, Michael J.; Quinn, Charles T.; Ichord, Rebecca; Dowling, Michael M.; Miller, J. Philip; DeBaun, Michael R

    2014-01-01

    Children with sickle cell anemia have a high prevalence of silent cerebral infarcts (SCIs) that are associated with decreased full-scale intelligence quotient (FSIQ). While the educational attainment of parents is a known strong predictor of the cognitive development of children in general, the role of parental education in sickle cell anemia along with other factors that adversely affect cognitive function (anemia, cerebral infarcts) is not known. We tested the hypothesis that both the prese...

  9. 'Theory of incomprehensibility'--the social and biological determinants of mental disorders.

    Science.gov (United States)

    Kapusta, Andrzej

    2013-01-01

    Karl Jaspers' theory on the incomprehensibility of psychotic disorders has become the reference point for many critical studies in the field of contemporary psychopathology. According to Jaspers, it is impossible to understand any of the serious mental disorders often referred to as 'psychosis' because of their unreasonableness, a truth that is revealed when one attempts to empathize with the mental states of patients afflicted with a particular mental disorder. These elements are psychologically inaccessible and closed to any form of empathy. The theory of incomprehensibility is the starting point for many contemporary discussions on the nature of mental illness. It refers to the pathogenic causes of mental disorder and, at the same time, leads to the marginalization of 'pathoplastic'--personal, family related and environmental factors responsible for mental distress. The presented article criticizes the theory of incomprehensibility in light of the contemporary discussion within the (new) philosophy of psychiatry about the role and function of psychiatry and psychopathology. Many authors criticize the theory of incomprehensibility, particularly its implications for understanding and explaining mental disorders. The views presented in the article--post-psychiatry, the psychiatry of common sense, the socio-cultural approach and engaged epistemology/embodied cognition--aim to reveal the broader dimensions of human pathological experience. Particularly appreciated by the author, engaged epistemology and embodied cognition aim to connect social and experiential points of view with the more scientific neuropsychiatric research, and refer to the hidden levels of our experience while always placing such elements in the social context, as well as describing human pathological symptoms against this social background. The basic aim of the presented paper is to stress the need for a review of dogmatic assumptions on the nature of mental illness, and to discuss the

  10. Role of surface charge in determining the biological effects of CdSe/ZnS quantum dots

    Directory of Open Access Journals (Sweden)

    Liu QQ

    2015-11-01

    Full Text Available Qiangqiang Liu,1,* Hongxia Li,1,* Qiyue Xia,1 Ying Liu,1 Kai Xiao,1,2 1National Chengdu Center for Safety Evaluation of Drugs, State Key Laboratory of Biotherapy, Collaborative Innovation Center for Biotherapy, West China Hospital, 2Laboratory of Non-Human Primate Disease Model Research, State Key Laboratory of Biotherapy, Collaborative Innovation Center for Biotherapy, West China Hospital, Sichuan University, Chengdu, People’s Republic of China *These authors contributed equally to this work Abstract: The growing potential of quantum dots (QDs in biomedical applications has provoked the urgent need to thoroughly address their interaction with biological systems. However, only limited studies have been performed to explore the effects of surface charge on the biological behaviors of QDs. In the present study, three commercially available QDs with different surface coatings were used to systematically evaluate the effects of surface charge on the cellular uptake, cytotoxicity, and in vivo biodistribution of QDs. Our results demonstrated that charged QDs entered both cancer cells and macrophages more efficiently than neutral ones, while negative QDs internalized mostly. Upon entry into cells, QDs were localized in different subcellular compartments (eg, cytoplasm and lysosomes depending on the surface charge. Interestingly, inconsistent with the result of internalization, positive QDs but not negative QDs exhibited severe cytotoxicity, which was likely due to their disruption of cell membrane integrity, and production of reactive oxygen species. Biodistribution studies demonstrated that negative and neutral QDs preferentially distributed in the liver and the spleen, whereas positive QDs mainly deposited in the kidney with obvious uptake in the brain. In general, surface charge plays crucial roles in determining the biological interactions of QDs. Keywords: cellular uptake, uptake pathways, intracellular distribution, reactive oxygen species

  11. A metatheory integrating social, biological and technological factors in information behavior research

    Directory of Open Access Journals (Sweden)

    Leon James

    2014-06-01

    Full Text Available A metatheory is presented and diagrammed as an integrated conceptual framework for information seeking and use. It represents the symbiotic relationship between users and the technological environment. Receiving and adapting to information is achieved through each user’s biological satisficing procedures defined by group information practices, namely, noticing information, appraising it and evaluating it. Information use is achieved through optimizing procedures, namely, activating goal-setting intentions, constructing a plan and executing it through acting upon the technological environment to attain one’s goals. Evidence is given by listing a variety of information seeking behaviors that others have identified in their review of the literature, then showing how each element fits within the model, as well as by analyzing the interpretive discourse of college students while engaged in carrying out assigned information tasks. Each discourse segment in the samples was categorized as either an affective, cognitive or sensorimotor procedure carried out by the user, and transcribed as a string or sequence. This code sequence was then compared with the sequence produced when the model’s mapping is followed. Every discourse sample inspected contained the six categories specified by the model. The metatheory is suitable for providing a common framework for discussing various areas of information behavior research.

  12. Synergistic effect of carbon monoxide with other biologically active injurious factors on the organism

    Energy Technology Data Exchange (ETDEWEB)

    Pankow, D.; Ponsold, W.

    1974-09-01

    The combined effects on biological organisms are reported for carbon monoxide and carbon dioxide, nitrogen oxides, sodium nitrite, hydrocyanic acid, carbon disulfide, sulfur dioxide, ammonia, hydrogen peroxide, ethanol, trichloroethylene, carbon tetrachloride, methane, benzene, iodine acetate, cholesterol, benzpyrene, hexobarbitol, zoxazolamine, nembutal, luminal, morphine, adrenalin, persantin, cytochrome c, aldrin, carbaryl, cyclodiene epoxide; and physical influences such as ambient temperature, atmospheric pressure, ionizing radiation, noise, and vibration. A literature review shows that with increasing CO/sub 2/ and decreasing oxygen concentration in the inhalation air, the toxicity of CO increased in experiments with mice and canaries. Oxides of nitrogen enhance the toxic effect of CO in an additive way and at times synergistically. At 500 m from a metallurgical plant in the USSR the maximum allowable immission concentrations for CO and SO/sub 2/ were exceeded. In children residing there a higher normal erythrocyte number, hemoglobin content, and catalase activity were found in the blood along with higher concentrations of coproporphyrin and 17-ketosteroids. All values returned to normal after an 8-week stay of these children away from the metallurgical plant.

  13. Biological significance of the focus on DNA damage checkpoint factors remained after irradiation of ionizing radiation

    International Nuclear Information System (INIS)

    This paper reviews recent reports on the focus formation and participation to checkpoint of (such phosphorylated (P-d) as below) ATM and H2AX, MDC1, 53BP1 and NBS1, and discusses their role in DNA damage checkpoint induction mainly around authors' studies. When the cell is irradiated by ionizing radiation, the subtype histone like H2AX is P-d and the formed focus', seen in the nucleus on immuno-fluorographic observation, represents the P-d H2AX at the damaged site of DNA. The role of P-d ATM (the product of causative gene of ataxia-telangiectasia mutation, a protein kinase) has been first shown by laser beam irradiation. Described are discussions on the roles and functions after irradiation in focus formation and DNA damage checkpoint of P-d H2AX (a specific histone product by the radiation like γ-ray as above), P-d ATM, MDC1 (a mediator of DNA damage check point protein 1), 53BP1, (a p53 binding protein) and NBS1 (the product of the causative gene of Nijmegen Breakage Syndrome). Authors have come to point out the remained focal size increase as implications of the efficient repair of damaged DNA, and the second cycled p53 accumulation, of tumor suppression. Thus evaluation of biological significance of these aspects, scarcely noted hitherto, is concluded important. (S.I.)

  14. Lead and cadmium determinations by atomic absorption technique in biological samples: blood, placenta and umbilical cord

    International Nuclear Information System (INIS)

    In order to determine the possibility contamination of lead and cadmium in pregnant women living in the mining-smelting city of La Oroya in Peru, lead and cadmium concentrations were assessed in maternal blood (pre-birth), umbilical cord blood and placental tissue. Forty deliveries with normal evolution were evaluated between October 2002 and January 2003. Samples were analyzed by atomic absorption on a graphite furnace at the Peruvian Institute of Nuclear Energy (IPEN) laboratories. Results are summarized as follows: a) Mean lead concentrations in maternal blood (MB), umbilical cord blood (UCB) and placental tissue (PT) were 27.23 μg/dL, 18.48 μg/dL and 363.97 μg/100g, respectively; b) Mean cadmium concentrations in MB, UCB and PT were 8.82 μg/dL, 12,0 μg/dL and 104,44 μg/100g, respectively; c) The correlation coefficient between lead concentration in maternal blood and umbilical cord was 0.122; d). The correlation coefficient of cadmium concentration between MB and UCB was 0.223; e). The correlation coefficient of lead concentration between MB and PT was 0.189; f). The correlation coefficient of cadmium concentration between MB and PT was 0.633. Trans-placental transport of lead was 67.84% (27,23 μg/dL in MB vs. 18.48 μg/dL in UCB); whereas in the case of cadmium, the concentration in UC (12,00 μg/dL) was greater than in MB (8.82 μg/dL.). These results could indicate that the placenta acts as a barrier trapping lead and cadmium. This barrier is efficient for lead since the concentration in cord blood is inferior to maternal blood but it is less efficient for cadmium. (author)

  15. Use of AERMOD to Determine a Hydrogen Sulfide Emission Factor for Swine Operations by Inverse Modeling.

    Science.gov (United States)

    O'Shaughnessy, Patrick T; Altmaier, Ralph

    2011-08-01

    This study was conducted to determine both optimal settings applied to the plume dispersion model, AERMOD, and a scalable emission factor for accurately determining the spatial distribution of hydrogen sulfide concentrations in the vicinity of swine concentrated animal feeding operations (CAFOs). These operations emit hydrogen sulfide from both housing structures and waste lagoons. With ambient measurements made at 4 stations within 1 km of large swine CAFOs in Iowa, an inverse-modeling approach applied to AERMOD was used to determine hydrogen sulfide emission rates. CAFO buildings were treated as volume sources whereas nearby lagoons were modeled as area sources. The robust highest concentration (RHC), calculated for both measured and modeled concentrations, was used as the metric for adjusting the emission rate until the ratio of the two RHC levels was unity. Utilizing this approach, an average emission flux rate of 0.57 µg/m(2)-s was determined for swine CAFO lagoons. Using the average total animal weight (kg) of each CAFO, an average emission factor of 6.06 × 10(-7) µg/yr-m(2)-kg was calculated. From studies that measured either building or lagoon emission flux rates, building fluxes, on a floor area basis, were considered equal to lagoon flux rates. The emission factor was applied to all CAFOs surrounding the original 4 sites and surrounding an additional 6 sites in Iowa, producing an average modeled-to-measured RHC ratio of 1.24. When the emission factor was applied to AERMOD to simulate the spatial distribution of hydrogen sulfide around a hypothetical large swine CAFO (1M kg), concentrations 0.5 km from the CAFO were 35 ppb and dropped to 2 ppb within 6 km of the CAFO. These values compare to a level of 30 ppb that has been determined by the State of Iowa as a threshold level for ambient hydrogen sulfide levels.

  16. Immunochemical determination of cellular content of translation release factor RF4 in Escherichia coli

    DEFF Research Database (Denmark)

    Andersen, Lars Dyrskjøt; Manuel Palacios Moreno, Juan; Clark, Brian F. C.;

    1999-01-01

    The biosynthesis of proteins in prokaryotes is terminated when a stop codon is present in the A-site of the 70S ribosomal complex. Four different translation termination factors are known to participate in the termination process. Release factor RF1 and RF2 are responsible for the recognition...... of RF1, RF2, and RF3 were determined earlier. Here we report the cellular content of RF4 in Escherichia coli to be approximately 16,500 molecules per cell. The cells were grown in a rich medium and harvested in the beginning of the exponential growth phase. The quantifications were performed by using...

  17. [Mechanisms underlying physiological functions of food factors via non-specific interactions with biological proteins].

    Science.gov (United States)

    Murakami, Akira

    2015-01-01

      We previously reported that zerumbone, a sesquiterpene found in Zingiber zerumbet SMITH, showed notable cancer preventive effects in various organs of experimental rodents. This agent up-regulated nuclear factor-E2-related factor (Nrf2)-dependent expressions of anti-oxidative and xenobiotics-metabolizing enzymes, leading to an increased self-defense capacity. On the other hand, zerumbone markedly suppressed the expression of cyclooxygenase-2, an inducible pro-inflammatory enzyme, by disrupting mRNA stabilizing processes. Binding experiments using a biotin derivative of zerumbone demonstrated that Keap1, an Nrf2 repressive protein, is one of its major binding proteins that promotes their dissociation for inducing Nrf2 transactivation. We then generated a specific antibody against zerumbone-modified proteins and found that zerumbone modified numerous cellular proteins in a non-specific manner, with global distribution of the modified proteins seen not only in cytoplasm but also the nucleus. Based on those observations, zerumbone was speculated to cause proteo-stress, a notion supported by previous findings that it increased the C-terminus of Hsc70 interacting protein-dependent protein ubiquitination and also promoted aggresome formation. Interestingly, zerumbone counteracted proteo-stress and heat stress via up-regulation of the protein quality control systems (PQCs), e.g., heat shock proteins (HSPs), ubiquitin-proteasome, and autophagy. Meanwhile, several phytochemicals, including ursolic acid and curcumin, were identified as marked HSP70 inducers, whereas most nutrients tested were scarcely active. Recent studies have revealed that PQCs play important roles in the prevention of many lifestyle related diseases, such as cancer, thus non-specific binding of phytochemicals to cellular proteins may be a novel and unique mechanism underlying their physiological activities.

  18. LOSS FACTOR AND DYNAMIC YOUNG MODULUS DETERMINATION FOR COMPOSITE SANDWICH BARS REINFORCED WITH STEEL FABRIC

    Directory of Open Access Journals (Sweden)

    Cosmin-Mihai MIRIŢOIU

    2015-05-01

    Full Text Available In this paper I have build some composite sandwich bars. For these bars I have determined the dynamic response by recording their free vibrations. These bars have the core made of polypropylene honeycomb with upper and lower layers reinforced with steel wire mesh. For these bars I have determined the the eigenfrequency of the first eigenmode in this way: the bar was embedded at one end and free at the other where there was placed an accelerometer at 10 mm distance from the edge and I applied an initial force at the free end. I have determined the eigenfrequency because I will use its values for the loss factor and dynamic Young modulus determination.

  19. Integral emission factors for methane determined using urban flux measurements and local-scale inverse models

    Science.gov (United States)

    Christen, Andreas; Johnson, Mark; Molodovskaya, Marina; Ketler, Rick; Nesic, Zoran; Crawford, Ben; Giometto, Marco; van der Laan, Mike

    2013-04-01

    The most important long-lived greenhouse gas (LLGHG) emitted during combustion of fuels is carbon dioxide (CO2), however also traces of the LLGHGs methane (CH4) and nitrous oxide (N2O) are released, the quantities of which depend largely on the conditions of the combustion process. Emission factors determine the mass of LLGHGs emitted per energy used (or kilometre driven for cars) and are key inputs for bottom-up emission modelling. Emission factors for CH4 are typically determined in the laboratory or on a test stand for a given combustion system using a small number of samples (vehicles, furnaces), yet associated with larger uncertainties when scaled to entire fleets. We propose an alternative, different approach - Can integrated emission factors be independently determined using direct micrometeorological flux measurements over an urban surface? If so, do emission factors determined from flux measurements (top-down) agree with up-scaled emission factors of relevant combustion systems (heating, vehicles) in the source area of the flux measurement? Direct flux measurements of CH4 were carried out between February and May, 2012 over a relatively densely populated, urban surface in Vancouver, Canada by means of eddy covariance (EC). The EC-system consisted of an ultrasonic anemometer (CSAT-3, Campbell Scientific Inc.) and two open-path infrared gas analyzers (Li7500 and Li7700, Licor Inc.) on a tower at 30m above the surface. The source area of the EC system is characterised by a relative homogeneous morphometry (5.3m average building height), but spatially and temporally varying emission sources, including two major intersecting arterial roads (70.000 cars drive through the 50% source area per day) and seasonal heating in predominantly single-family houses (natural gas). An inverse dispersion model (turbulent source area model), validated against large eddy simulations (LES) of the urban roughness sublayer, allows the determination of the spatial area that

  20. Aspects of accuracy and precision in the determination of As and Sb in biological materials by neutron activation analysis

    International Nuclear Information System (INIS)

    Aspects of accuracy and precision on the analysis of As and Sb in biological materials using neutron activation with post-irradiation separation are discussed. The separation technique is based on hydride generation. The average yield is over 98% for As and over 95% for Sb, but differences between samples necessitate a yield determination for each sample. Both radiotracers and reactivation have been applied and their practical use for yield correction is discussed. Under optimised conditions, As in NBS SRM 1577A has been analysed to be 45.5 ± 0.7 μg/kg (N = 4), while the Sb-content points to 2.3 ± 1.0 μg/kg (N = 11). 3 figs.; 20 refs.; 5 tabs

  1. New biological potential of abietane diterpenoids isolated from Salvia austriaca against microbial virulence factors.

    Science.gov (United States)

    Sadowska, Beata; Kuźma, Łukasz; Micota, Bartłomiej; Budzyńska, Aleksandra; Wysokińska, Halina; Kłys, Arkadiusz; Więckowska-Szakiel, Marzena; Różalska, Barbara

    2016-09-01

    The increasing importance of multi-resistant strains and microbial biofilms in the development of chronic infections has driven the search for more effective alternative therapy including plant-origin preparations. The present study evaluates the broadly-defined antimicrobial activity of two abietane diterpenoids isolated from Salvia austriaca transformed roots: taxodone and 15-deoxy-fuerstione. The direct biostatic/biocidal effect of these phytocompounds and their influence on Staphylococcus aureus and Candida albicans virulence factors/mechanisms (adhesion, biofilm formation, agglutination in human plasma, survival in the blood, germ tube and mycelium formation) were tested using in vitro assays. Both phytocompounds significantly inhibited microbial adhesion and biofilm formation when used at ½ and ¼ MIC. Additionally, taxodone was able to limit staphylococcal survival in human blood, as well as C. albicans germ tube formation and hyphal growth. The tested diterpenoids express significant anti-biofilm activity against both staphylococci and yeast, and adversely affect their virulence factors/mechanisms, which are relevant in the course of the infection in vivo. Therefore, they demonstrate considerable biomedical potential as complements for classic therapy with antibiotics. PMID:27417191

  2. Determination of four sulfated vitamin D compounds in human biological fluids by liquid chromatography-tandem mass spectrometry.

    Science.gov (United States)

    Gomes, Fabio P; Shaw, P Nicholas; Hewavitharana, Amitha K

    2016-01-15

    The determination of both the water-soluble and lipid-soluble vitamin D compounds in human biological fluids is necessary to illuminate potentially significant biochemical mechanisms. The lack of analytical methods to quantify the water-soluble forms precludes studies on their role and biological functions; currently available liquid chromatography-tandem mass spectrometry (LC-MS/MS) methods are able to determine only a single sulfated form of Vitamin D. We describe here a highly sensitive and specific LC-MS/MS method for the quantification of four sulfated forms of vitamin D: vitamins D2- and D3-sulfate (D2-S and D3-S) and 25-hydroxyvitamin D2- and D3-sulfate (25(OH)D2-S and 25(OH)D3-S). A comparative evaluation showed that the ionization efficiencies of underivatized forms in negative ion mode electrospray ionisation (ESI) are superior to those of the derivatized (using 4-phenyl-l,2,4-triazoline-3,5-dione (PTAD)) forms in positive ion mode ESI. Separation was optimised to minimise co-elution with endogenous matrix compounds, thereby reducing ion suppression/enhancement effects. Isotopically labelled analogues of each compound were used as internal standards to correct for ion suppression/enhancement effects. The method was validated and then applied for the analysis of breastmilk and human serum. The detection limits, repeatability standard deviations, and recoveries ranged from 0.20 to 0.28fmol, 2.8 to 10.2%, and 81.1 to 102%, respectively. PMID:26708628

  3. Determinations of soil-plant transfer factors for Dutch soils (1981-1983)

    International Nuclear Information System (INIS)

    Determinations of the uptake of potentially dangerous radionuclides from soil under different experimental conditions have been performed. To determine transfer factors under conditions, which simulate farmland as closely as possible, a lysimeter has been constructed. It is suitable for long term experiments and consists of 32 containers filled with three different types of Dutch soil: loess, sandy soil and river clay. The soils have been labelled with 54Mn, 60Co, 65Zn, 90Sr and 137Cs, i.e. three activated corrosion products and two fission products. (Auth.)

  4. Determining Student Internet Addiction Levels in Secondary Education and the Factors that Affect It

    OpenAIRE

    Fezile Ozdamli; Ozge Beyatli

    2013-01-01

    The aim of this research is to determine the level of internet addiction on the part of students in secondary education in North Cyprus and the factors that affect it. In this research, a survey method which provides a general universal judgment was used to determine the level of internet addiction on the part of such students. It has been found that 59.9% of the students are at low of becoming internet addicts, 20.7% of them are in the high risk category, 13.5% face no risk of addiction, whi...

  5. Determination of the anomalous scattering factors of high-Z atoms using bremsstrahlung radiation

    International Nuclear Information System (INIS)

    The anomalous scattering factors (f' and f'') of tungsten, gold and lead atoms have been determined using external bremsstrahlung (EB) photons. The EB photons are produced by the interaction of a beta particle from a beta source with a nickel target. These photons are allowed to pass through thin targets of tungsten, gold and lead. The transmitted photons have been measured by using a GMX-type HPGe detector coupled to an 8K multichannel analyser. The transmitted spectra show a sharp decrease in intensity at the K shell binding energies of the target atoms. The regions around the decreased portion have been used to determine the anomalous scattering factors. The experimentally measured values are compared with the available theoretical values.

  6. Determination of the anomalous scattering factors of high-Z atoms using bremsstrahlung radiation

    Energy Technology Data Exchange (ETDEWEB)

    Hosur, Savita B; Naik, L R; Badiger, N M [Department of Physics, Karnatak University, Dharwad 580003 (India)], E-mail: nagappa123@yahoo.co.in

    2009-02-14

    The anomalous scattering factors (f' and f'') of tungsten, gold and lead atoms have been determined using external bremsstrahlung (EB) photons. The EB photons are produced by the interaction of a beta particle from a beta source with a nickel target. These photons are allowed to pass through thin targets of tungsten, gold and lead. The transmitted photons have been measured by using a GMX-type HPGe detector coupled to an 8K multichannel analyser. The transmitted spectra show a sharp decrease in intensity at the K shell binding energies of the target atoms. The regions around the decreased portion have been used to determine the anomalous scattering factors. The experimentally measured values are compared with the available theoretical values.

  7. Determination of small-field correction factors for cylindrical ionization chambers using a semiempirical method

    Science.gov (United States)

    Park, Kwangwoo; Bak, Jino; Park, Sungho; Choi, Wonhoon; Park, Suk Won

    2016-02-01

    A semiempirical method based on the averaging effect of the sensitive volumes of different air-filled ionization chambers (ICs) was employed to approximate the correction factors for beam quality produced from the difference in the sizes of the reference field and small fields. We measured the output factors using several cylindrical ICs and calculated the correction factors using a mathematical method similar to deconvolution; in the method, we modeled the variable and inhomogeneous energy fluence function within the chamber cavity. The parameters of the modeled function and the correction factors were determined by solving a developed system of equations as well as on the basis of the measurement data and the geometry of the chambers. Further, Monte Carlo (MC) computations were performed using the Monaco® treatment planning system to validate the proposed method. The determined correction factors (k{{Q\\text{msr}},Q}{{f\\text{smf}}, {{f}\\text{ref}}} ) were comparable to the values derived from the MC computations performed using Monaco®. For example, for a 6 MV photon beam and a field size of 1  ×  1 cm2, k{{Q\\text{msr}},Q}{{f\\text{smf}}, {{f}\\text{ref}}} was calculated to be 1.125 for a PTW 31010 chamber and 1.022 for a PTW 31016 chamber. On the other hand, the k{{Q\\text{msr}},Q}{{f\\text{smf}}, {{f}\\text{ref}}} values determined from the MC computations were 1.121 and 1.031, respectively; the difference between the proposed method and the MC computation is less than 2%. In addition, we determined the k{{Q\\text{msr}},Q}{{f\\text{smf}}, {{f}\\text{ref}}} values for PTW 30013, PTW 31010, PTW 31016, IBA FC23-C, and IBA CC13 chambers as well. We devised a method for determining k{{Q\\text{msr}},Q}{{f\\text{smf}}, {{f}\\text{ref}}} from both the measurement of the output factors and model-based mathematical computation. The proposed method can be useful in case the MC simulation would not be applicable for the clinical settings.

  8. Prenatal stress is a vulnerability factor for altered morphology and biological activity of microglia cells.

    Directory of Open Access Journals (Sweden)

    Joanna eŚlusarczyk

    2015-03-01

    Full Text Available Several lines of evidence suggest that the dysregulation of the immune system is an important factor in the development of depression. Microglia are the resident macrophages of the central nervous system and a key player in innate immunity of the brain. We hypothesized that prenatal stress (an animal model of depression as a priming factor could affect microglial cells and might lead to depressive-like disturbances in adult male rat offspring. We investigated the behavioral changes (sucrose preference test, Porsolt test, the expression of C1q and CD40 mRNA and the level of microglia (Iba1 positive in 3 month old control and prenatally stressed male offspring rats. In addition, we characterized the morphological and biochemical parameters of potentially harmful (NO, iNOS, IL-1β, IL-18, IL-6, TNF-α, CCL2, CXCL12, CCR2, CXCR4 and beneficial (IGF-1, BDNF phenotypes in cultures of microglia obtained from the cortices of 1-2 days old control and prenatally stressed pups. The adult prenatally stressed rats showed behavioral (anhedonic- and depression-like disturbances, enhanced expression of microglial activation markers and an increased number of Iba1-immunopositive cells in the hippocampus and frontal cortex. The morphology of glia was altered in cultures from prenatally stressed rats, as demonstrated by immunofluorescence microscopy. Moreover, in these cultures, we observed enhanced expression of CD40 and MHC II and release of pro-inflammatory cytokines, including IL-1β, IL-18, TNF-α and IL-6. Prenatal stress significantly up-regulated levels of the chemokines CCL2, CXCL12 and altered expression of their receptors, CCR2 and CXCR4 while IGF-1 production was suppressed in cultures of microglia from prenatally stressed rats.Our results suggest that prenatal stress may lead to excessive microglia activation and contribute to the behavioral changes observed in depression in adulthood.

  9. Factors determining noncompliance to mass drug administration for lymphatic filariasis elimination

    OpenAIRE

    Zinia T. Nujum; Remadevi, S; Nirmala, C.; Rajmohanan, K; Indu, PS; Nair, S. Muraleedharan

    2012-01-01

    Mass Drug Administration (MDA) for Lymphatic Filariasis (LF) elimination has been implemented worldwide and in India with a goal of eliminating the disease by 2020 and 2015 respectively. Compliance to MDA is less than adequate to achieve the goal in the desired time. This study aims to identify the factors related to awareness, acceptability and attitude and the role of certain theoretical constructs of health belief model in determining the compliant behavior to MDA. Within a cross-sectional...

  10. Simultaneous Spectrophotometric Determination of Four Components including Acetaminophen by Taget Factor Analysis

    Institute of Scientific and Technical Information of China (English)

    2007-01-01

    UV Spectrophotometric Target Factor Analysis (TFA) was used for the simultaneous determination of four components (acetaminophen, guuaifenesin, caffeine, Chlorphenamine maleate) in cough syrup. The computer program of TFA is based on VC++ language. The difficulty of overlapping of absorption spectra of four compounds was overcome by this procedure. The experimental results show that the average recovery of each component is all in the range from 98.9% to 106.8% and each component obtains satisfactory results without any pre-separation.

  11. Socioeconomic Determinants of Nutritional Status of Children in Lao PDR: Effects of Household and Community Factors

    OpenAIRE

    Kamiya, Yusuke

    2011-01-01

    The prevalence of undernutrition among Lao children is among the highest in the region. However, the determinants of childhood undernutrition in Laos have not been fully analyzed. This paper, using the dataset of the Lao Multiple Indicator Cluster Survey 3, which is a nationally-representative sample in Laos, investigated the effects of socioeconomic factors at both household and community levels on the nutritional status of children. In the estimation, a multilevel linear model with random-i...

  12. Determining Factors for Delisting of Companies Listed on BM&FBOVESPA

    Directory of Open Access Journals (Sweden)

    Patricia Maria Bortolon

    2015-08-01

    Full Text Available Traditionally, the capital market has attracted the interest of scholars and researchers, motivated to understand the process of going public and trading securities of companies on a stock exchange. In this research context, an aspect had been neglected, something which indi cates a gap in the body of knowledge about the capital market and corporate governance: delisting of companies. We aim to identify the determining factors for delisting companies from the Commodity & Futures Exchange BOVESPA (BM&FBOVESPA. Methodologically, this research has related a set of variables collected from secondary data available on the database of the Securities Commission of Brazil (CVM, BM&FBOVESPA, and Economatica. By analyzing 227 listing cancellations, between 2001 and 2012, the results indicate that de listing of companies from BM&FBOVESPA is determined by the following factors: (i greater concentration of ownership and control; (ii lower free float; (iii lower liquidity of shares; (iv greater availability of cash; and (v larger size. The fact that the controlling shareholder is a public or private company determines significant differences in the decision to delist. While in the first case cash availability is the most important factor, in the second liquidity is the main determining factor for delisting. From the academic viewpoint, this research extends the studies on delisting, still incipient in the Brazilian capital market context. For the capital market, identifying the characteristics of companies prone to cancel listing may prevent investors concerned about inherent risks at the time of acquiring shares by the controlling group interested in delisting.

  13. Personal factors of burnout syndrome in teachers in the framework of self-determination theory

    OpenAIRE

    Ranđelović Kristina; Stojiljković Snežana; Milojević Milica

    2013-01-01

    Teachers perform numerous professional roles that can serve as the source of prolonged stress and lead to the occurrence of burnout syndrome. This research was aimed at studying the personal factors of burnout, using self-determination theory as a starting point. We used a sample of 200 teachers to study the following: the level of satisfaction of basic psychological needs at work, the prominence of self-orientations and the presence of burnout syndrome. We...

  14. Influence of chemical and biological factors on trophic transfer of persistent organic pollutants in the northwater polynya marine food web.

    Science.gov (United States)

    Fisk, A T; Hobson, K A; Norstrom, R J

    2001-02-15

    Persistent organic pollutants (POPs) and stable isotopes of nitrogen (delta 15N) were measured in zooplankton (6 species), a benthic invertebrate (Anonyx nugax), Arctic cod (Boreogadus saida), seabirds (6 species), and ringed seals (Phoca hispida) collected in 1998 in the Northwater Polynya to examine effects of biological and chemical factors on trophic transfer of POPs in an Arctic marine food web. Strong positive relationships were found between recalcitrant POP concentrations (lipid corrected) and trophic level based on stable isotopes of nitrogen, providing clear evidence of POP biomagnification in Arctic marine food webs. Food web magnification factors (FWMFs), derived from the slope of the POP--trophic level relationship, provided an overall magnification factor for the food web but over and underestimated biomagnification factors (BMFs) based on predator--prey concentrations in poikilotherms (fish) and homeotherms (seabirds and mammals), respectively. Greater biomagnification in homeotherms was attributed to their greater energy requirement and subsequent feeding rates. Within the homeotherms, seabirds had greater BMFs than ringed seals, consistent with greater energy demands in birds. Scavenging from marine mammal carcasses and accumulation in more contaminated winter habitats were considered important variables in seabird BMFs. Metabolic differences between species resulted in lower than expected BMFs, which would not be recognized in whole food web trophic level--POP relationships. The use of sigma POP groups, such as sigma PCB, is problematic because FWMFs and BMFs varied considerably between individual POPs. FWMFs of recalcitrant POPs had a strong positive relationship with log octanol--water partition coefficient (Kow). Results of this study show the utility of using delta 15N to characterize trophic level and trophic transfer of POPs but highlight the effects of species and chemical differences on trophic transfer of POPs that can be overlooked when

  15. Social and behavioral determinants of perceived insufficient sleep: analysis of the behavioral risk factor surveillance system

    Directory of Open Access Journals (Sweden)

    Michael A Grandner

    2015-06-01

    Full Text Available Background: Insufficient sleep is associated with cardiometabolic disease and poor health. However, few studies have assessed its determinants in a nationally-representative sample. Methods: Data from the 2009 Behavioral Risk Factor Surveillance System (BRFSS was used (N=323,047 adults. Insufficient sleep was assessed as insufficient rest/sleep over 30 days. This was evaluated relative to sociodemographics (age, sex, race/ethnicity, marital status, region, socioeconomics (education, income, employment, insurance, health behaviors (diet, exercise, smoking, alcohol, and health/functioning (emotional support, BMI, mental/physical health. Results: Overall, insufficient sleep was associated with being female, White or Black/African-American, unemployed, without health insurance, and not married; decreased age, income, education, physical activity; worse diet and overall health; and increased household size, alcohol, and smoking. Conclusion: These factors should be considered risk factors for insufficient sleep.

  16. Determining factors for the adoption of stock option plans in brazilian publicly traded companies

    Directory of Open Access Journals (Sweden)

    Geovanne Dias de Moura

    2016-08-01

    Full Text Available The objective was to identify the determining factors for the adoption of stock option plans in Brazilian publicly traded companies. Therefore, a descriptive research was developed by means of document analysis and a quantitative approach, using logistic regression. The sample consists of 158 companies, using data for the period from 2009 till 2012. The results evidenced an increase in the number of companies with stock option plans during the period. Among the factors company size, liquidity constraint, stock concentration, horizon problem, stockholder participation of CEO, dual function of CEO and chairman of the board, described in the literature as influences for the use of stock option plans, three were confirmed in the sample analyzed. The factors “current liquidity” between 2010 and 2012; “horizon problem” between 2009 and 2012; and “stockholder participation” in 2012, further evidence positive relations in the Brazilian context.

  17. Determination of g-factor in a quantum well channel with a strong Rashba effect

    Energy Technology Data Exchange (ETDEWEB)

    Choi, Won Young; Cheol Koo, Hyun, E-mail: hckoo@kist.re.kr [Spin Convergence Research Center, Korea Institute of Science and Technology, Seoul 136-791 (Korea, Republic of); KU-KIST Graduate School of Converging Science and Technology, Korea University, Seoul 136-701 (Korea, Republic of); Chang, Joonyeon; Hoon Lee, Jung [Spin Convergence Research Center, Korea Institute of Science and Technology, Seoul 136-791 (Korea, Republic of)

    2014-05-07

    Using the Shubnikov−de Haas oscillation measurement, the g-factor of carriers in a strong Rashba system is observed. To determine g-factor of carriers in the InAs quantum well channel with a strong Rashba effect, the magnetic fields are simultaneously applied along the in-plane direction and the perpendicular direction. The perpendicular field drives the oscillation of conductance for measuring Rashba spin orbit interaction and the in-plane field parallel to the Rashba field interacts with Rashba effect and modifies the intrinsic Rashba parameter. The total field inside the channel is a combination of the Rashba field and the in-plane field, so the modification of Rashba parameter gives a g-factor value of ∼13 in our system.

  18. Determination of the principal factors of river water quality through cluster analysis method and its prediction

    Institute of Scientific and Technical Information of China (English)

    Liang GUO; Ying ZHAO; Peng WANG

    2012-01-01

    In this paper, an artificial neural network model was built to predict the Chemical Oxygen Demand (CODMn) measured by permanganate index in Songhua River. To enhance the prediction accuracy, principal factors were determined through the analysis of the weight relation between influencing factors and forecasting object using cluster analysis method, which optimized the topological structure of the prediction model input items of the artificial neural network. It was shown that application of the principal factors in water quality prediction model can improve its forecasting skill significantly through the comparison between results of prediction by artificial neural network and the measurements of the CODMn. This methodology is also applicable to various water quality prediction targets of other water bodies and it is valuable for theoretical study and practical application.

  19. Social factors determining maternal and neonatal mortality in South Africa: A qualitative study

    Directory of Open Access Journals (Sweden)

    Rose M.M. Mmusi-Phetoe

    2016-02-01

    Full Text Available Background: South Africa’s maternal mortality ratio has increased from 150/100 000 in 1990 to 269/100 000 live births in 2015 against the Millennium Development Goals 5 (MDG5 target of 38/100 000, indicating slow progress in improving maternal health. The neonatal mortality rate was 14/1000 live births against the MDG4 target of 7/1000. The purpose of the article was to outline the socio-economic factors that determine maternal and neonatal mortality in South African communities.Objectives: To identify and describe the social determinants of maternal and neonatal mortality in South Africa. Method: A qualitative study using audio-taped individual interviews was conducted. The interviews included 10 pregnant women who were purposefully recruited from the antenatal clinic attendees in a public hospital. The interviews were conducted in isiZulu and later translated into English by the researcher who is fluent in both. Data were analysed using the World Health Organization’s (WHO Commission on Social Determinants of Health framework.Results: Findings revealed that poverty was an underlying factor to the vulnerability to illness and death of the mothers and their neonates. Other determinants were found to be the nutritional inadequacies, neglect and abuse by male partners, HIV or AIDS, inattention to reproductive health and violation of reproductive rights, and powerlessness of women and health system issues such as poor quality and incompetent health care.Conclusion: It is apparent that poverty plays a major role in determining the health of mothers and neonates. This requires more coordinated multi-sectorial interventions to address both the social determinants and direct causes of maternal and neonatal deaths.Keywords: maternal mortality, neonatal mortality, social determinants of health

  20. Gender Differences in Patients' Beliefs About Biological, Environmental, Behavioral, and Psychological Risk Factors in a Cardiac Rehabilitation Program

    Directory of Open Access Journals (Sweden)

    Mozhgan Saeidi

    2014-11-01

    Full Text Available Introduction: There are significant gender differences in the epidemiology and presentation of cardiovascular diseases (CVDs, physiological aspects of CVDs, response to diagnostic tests or interventions, and prevalence or incidence of the associated risk factors. Considering the independent influence of gender on early dire consequences of such diseases, this study was conducted to investigate gender differences in patients' beliefs about biological, environmental, behavioral, and psychological risk factors in a cardiac rehabilitation program. Materials and Methods: This study has cross sectional design. The sample was composed of 775 patients referred to cardiac rehabilitation unit in Imam Ali Hospital in Kermanshah, Iran. The data were collected using clinical interview and patients’ medical records. The data were analyzed using descriptive statistics such as mean, standard deviation, and chi-square test​​. To do the statistical analysis, SPSS version 20 was utilized. Results: As the results indicated, there was a significant difference between the beliefs of men and women about risk factors of heart disease (X2= 48.36; P