WorldWideScience

Sample records for acid-base imbalance

  1. Identifying acid-base and electrolyte imbalances.

    Science.gov (United States)

    Gooch, Michael D

    2015-08-15

    Acid-base and electrolyte imbalances often complicate patient management in acute care settings. Correctly identifying the imbalance and its cause is vital. This article will review the physiology of acid-base and electrolyte balance, their common disturbances, associated causes, clinical manifestations, and management implications for nurse practitioners.

  2. Effects of acid-base imbalance on vascular reactivity

    Directory of Open Access Journals (Sweden)

    A.C. Celotto

    2008-06-01

    Full Text Available Acid-base homeostasis maintains systemic arterial pH within a narrow range. Whereas the normal range of pH for clinical laboratories is 7.35-7.45, in vivo pH is maintained within a much narrower range. In clinical and experimental settings, blood pH can vary in response to respiratory or renal impairment. This altered pH promotes changes in vascular smooth muscle tone with impact on circulation and blood pressure control. Changes in pH can be divided into those occurring in the extracellular space (pHo and those occurring within the intracellular space (pHi, although, extracellular and intracellular compartments influence each other. Consistent with the multiple events involved in the changes in tone produced by altered pHo, including type of vascular bed, several factors and mechanisms, in addition to hydrogen ion concentration, have been suggested to be involved. The scientific literature has many reports concerning acid-base balance and endothelium function, but these concepts are not clear about acid-base disorders and their relations with the three known mechanisms of endothelium-dependent vascular reactivity: nitric oxide (NO/cGMP-dependent, prostacyclin (PGI2/cAMP-dependent and hyperpolarization. During the last decades, many studies have been published and have given rise to confronting data on acid-base disorder and endothelial function. Therefore, the main proposal of this review is to provide a critical analysis of the state of art and incentivate researchers to develop more studies about these issues.

  3. [Development and practice evaluation of blood acid-base imbalance analysis software].

    Science.gov (United States)

    Chen, Bo; Huang, Haiying; Zhou, Qiang; Peng, Shan; Jia, Hongyu; Ji, Tianxing

    2014-11-01

    To develop a blood gas, acid-base imbalance analysis computer software to diagnose systematically, rapidly, accurately and automatically determine acid-base imbalance type, and evaluate the clinical application. Using VBA programming language, a computer aided diagnostic software for the judgment of acid-base balance was developed. The clinical data of 220 patients admitted to the Second Affiliated Hospital of Guangzhou Medical University were retrospectively analyzed. The arterial blood gas [pH value, HCO(3)(-), arterial partial pressure of carbon dioxide (PaCO₂)] and electrolytes included data (Na⁺ and Cl⁻) were collected. Data were entered into the software for acid-base imbalances judgment. At the same time the data generation was calculated manually by H-H compensation formula for determining the type of acid-base imbalance. The consistency of judgment results from software and manual calculation was evaluated, and the judgment time of two methods was compared. The clinical diagnosis of the types of acid-base imbalance for the 220 patients: 65 cases were normal, 90 cases with simple type, mixed type in 41 cases, and triplex type in 24 cases. The accuracy of the judgment results of the normal and triplex types from computer software compared with which were calculated manually was 100%, the accuracy of the simple type judgment was 98.9% and 78.0% for the mixed type, and the total accuracy was 95.5%. The Kappa value of judgment result from software and manual judgment was 0.935, P=0.000. It was demonstrated that the consistency was very good. The time for software to determine acid-base imbalances was significantly shorter than the manual judgment (seconds:18.14 ± 3.80 vs. 43.79 ± 23.86, t=7.466, P=0.000), so the method of software was much faster than the manual method. Software judgment can replace manual judgment with the characteristics of rapid, accurate and convenient, can improve work efficiency and quality of clinical doctors and has great

  4. Delayed recovery due to exaggerated acid, base and electrolyte imbalance in prolonged laparoscopic repair of diaphragmatic hernia

    OpenAIRE

    Rakesh Garg; Jyotsna Punj; Ravindra Pandey; Vanlal Darlong

    2011-01-01

    The acid, base and electrolyte changes are usually observed in the perioperative settings. We report a case of prolonged laparoscopic repair of left-sided diaphragmatic hernia which involved a lot of tissue handling and fluid replacement leading to acid, base and electrolyte imbalance. A 42-year-old male underwent prolonged laparoscopic repair under general anesthesia. Intraoperatively, surgeon reported that contents of hernia includes bowel along with mesentery, spleen and lot of fatty tissu...

  5. Delayed recovery due to exaggerated acid, base and electrolyte imbalance in prolonged laparoscopic repair of diaphragmatic hernia.

    Science.gov (United States)

    Garg, Rakesh; Punj, Jyotsna; Pandey, Ravindra; Darlong, Vanlal

    2011-01-01

    The acid, base and electrolyte changes are usually observed in the perioperative settings. We report a case of prolonged laparoscopic repair of left-sided diaphragmatic hernia which involved a lot of tissue handling and fluid replacement leading to acid, base and electrolyte imbalance. A 42-year-old male underwent prolonged laparoscopic repair under general anesthesia. Intraoperatively, surgeon reported that contents of hernia includes bowel along with mesentery, spleen and lot of fatty tissue The blood loss was about 2 L which was replaced with 1 L of colloid and 7.5 L of lactated ringer. Near the end of surgery arterial blood gas analysis revealed metabolic acidosis, hyperkalemia, and hypocalcemia leading to delayed recovery. We conclude prolonged laparoscopic surgery involving lot of tissue handling including gut and fat should be monitored for acid, base, electrolyte imbalance and corrected timely to have uneventful rapid recovery.

  6. Neurologic presentations of acid-base imbalance, electrolyte abnormalities, and endocrine emergencies.

    Science.gov (United States)

    Yee, Alan H; Rabinstein, Alejandro A

    2010-02-01

    Accurate identification of nervous system dysfunction is vital in the assessment of any multisystem disorder. The neurologic manifestations of acid-base disturbances, abnormal electrolyte concentrations, and acute endocrinopathies are protean and typically determined by the acuity of the underlying derangement. Detailed history and physical examination may guide appropriate laboratory testing and lead to prompt and accurate diagnosis. Neurologic manifestations of primary and secondary systemic disorders are frequently encountered in all subspecialties of medicine. This article focuses on key neurologic presentations of respiratory and metabolic acid-base derangements and potentially life-threatening endocrinopathies.

  7. [Effect of acid-base imbalance on the equilibrium of elastase and its inhibitors in rat serum and aorta tissues].

    Science.gov (United States)

    Trofymova, I M; Dosenko, V Ie; Byts', Iu V

    2001-01-01

    In experiments on the acid-base imbalance modelling (acidosis induced with either lactate or ammonium chloride alcalosis induced with sodium hydrocarbonate) in rats, there were studied elastase activity, alpha-2-macroglobulin and alpha-1 proteinase inhibitor contents in blood serum and tissues of the aorta. The results obtained indicated that, in the models of both acidosis and alcalosis an disbalance between elastase and its inhibitors was observed. However, in NH4CL-acidosis in homogenates of aorta the inhibitors/elastase coefficient decreased at the expense of a reduction in contents of alpha-2-macroglobulin, while in lactate-acidosis it only decreased at the expense of an increase in elastase activity. In alcalosis, contents of proteinase inhibitors were even increased, however a substantial increase in elastase activity indicated a reduction in integrative coefficient. Similar changes were observed in blood serum, except elastase activity was considerably elevated in NH4CL-acidosis and did not change in lactate-acidosis. Thus, an disbalance in the elastolytic system associated with different types of acid-base imbalance can promote the destruction of elastic fibers of aorta, which is considered as one of initial mechanisms in pathogenesis of arteriosclerosis.

  8. Mixed acid-base disorders, hydroelectrolyte imbalance and lactate production in hypercapnic respiratory failure: the role of noninvasive ventilation.

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    Claudio Terzano

    Full Text Available BACKGROUND: Hypercapnic Chronic Obstructive Pulmonary Disease (COPD exacerbation in patients with comorbidities and multidrug therapy is complicated by mixed acid-base, hydro-electrolyte and lactate disorders. Aim of this study was to determine the relationships of these disorders with the requirement for and duration of noninvasive ventilation (NIV when treating hypercapnic respiratory failure. METHODS: Sixty-seven consecutive patients who were hospitalized for hypercapnic COPD exacerbation had their clinical condition, respiratory function, blood chemistry, arterial blood gases, blood lactate and volemic state assessed. Heart and respiratory rates, pH, PaO(2 and PaCO(2 and blood lactate were checked at the 1st, 2nd, 6th and 24th hours after starting NIV. RESULTS: Nine patients were transferred to the intensive care unit. NIV was performed in 11/17 (64.7% mixed respiratory acidosis-metabolic alkalosis, 10/36 (27.8% respiratory acidosis and 3/5 (60% mixed respiratory-metabolic acidosis patients (p = 0.026, with durations of 45.1 ± 9.8, 36.2 ± 8.9 and 53.3 ± 4.1 hours, respectively (p = 0.016. The duration of ventilation was associated with higher blood lactate (p<0.001, lower pH (p = 0.016, lower serum sodium (p = 0.014 and lower chloride (p = 0.038. Hyponatremia without hypervolemic hypochloremia occurred in 11 respiratory acidosis patients. Hypovolemic hyponatremia with hypochloremia and hypokalemia occurred in 10 mixed respiratory acidosis-metabolic alkalosis patients, and euvolemic hypochloremia occurred in the other 7 patients with this mixed acid-base disorder. CONCLUSIONS: Mixed acid-base and lactate disorders during hypercapnic COPD exacerbations predict the need for and longer duration of NIV. The combination of mixed acid-base disorders and hydro-electrolyte disturbances should be further investigated.

  9. Mixed acid-base disorders, hydroelectrolyte imbalance and lactate production in hypercapnic respiratory failure: the role of noninvasive ventilation.

    Science.gov (United States)

    Terzano, Claudio; Di Stefano, Fabio; Conti, Vittoria; Di Nicola, Marta; Paone, Gregorino; Petroianni, Angelo; Ricci, Alberto

    2012-01-01

    Hypercapnic Chronic Obstructive Pulmonary Disease (COPD) exacerbation in patients with comorbidities and multidrug therapy is complicated by mixed acid-base, hydro-electrolyte and lactate disorders. Aim of this study was to determine the relationships of these disorders with the requirement for and duration of noninvasive ventilation (NIV) when treating hypercapnic respiratory failure. Sixty-seven consecutive patients who were hospitalized for hypercapnic COPD exacerbation had their clinical condition, respiratory function, blood chemistry, arterial blood gases, blood lactate and volemic state assessed. Heart and respiratory rates, pH, PaO(2) and PaCO(2) and blood lactate were checked at the 1st, 2nd, 6th and 24th hours after starting NIV. Nine patients were transferred to the intensive care unit. NIV was performed in 11/17 (64.7%) mixed respiratory acidosis-metabolic alkalosis, 10/36 (27.8%) respiratory acidosis and 3/5 (60%) mixed respiratory-metabolic acidosis patients (p = 0.026), with durations of 45.1 ± 9.8, 36.2 ± 8.9 and 53.3 ± 4.1 hours, respectively (p = 0.016). The duration of ventilation was associated with higher blood lactate (pelectrolyte disturbances should be further investigated.

  10. CHARGE IMBALANCE

    Energy Technology Data Exchange (ETDEWEB)

    Clarke, John

    1980-09-01

    The purpose of this article is to review the theory of charge imbalance, and to discuss its relevance to a number of experimental situations. We introduce the concepts of quasiparticle charge and charge imbalance, and discuss the generation and detection of charge imbalance by tunneling. We describe the relaxation of the injected charge imbalance by inelastic scattering processes, and show how the Boltzmann equation can be solved to obtain the steady state quasiparticle distribution and the charge relaxation rate. Details are given of experiments to measure charge imbalance and the charge relaxation rate when inelastic scattering is the predominant relaxation mechanism. Experiments on and theories of other charge relaxation mechanisms are discussed, namely relaxation via elastic scattering in the presence of energy gap anisotropy, or in the presence of a pair breaking mechanism such as magnetic impurities or an applied supercurrent or magnetic field. We describe three other situations in which charge imbalance occurs, namely the resistance of the NS interface, phase slip centers, and the flow of a supercurrent in the presence of a temperature gradient.

  11. Acid base balance in blood and cerebrospinal fluid.

    Science.gov (United States)

    Horovitz, Y; Tal, I; Keynan, A

    1985-01-01

    Thirty four infants were studied; 21 with acute gastroenteritis, dehydration, and metabolic acidosis and 13 who served as controls. All infants with metabolic acidosis and without neurological signs had a normal to near normal cerebrospinal fluid acid base balance, but five with metabolic acidosis and severe neurological signs had cerebrospinal fluid acid base disequilibrium. Acute metabolic acidosis in infants may lead to cerebrospinal fluid acid base imbalance causing cerebral dysfunction. PMID:4015176

  12. Three Phase Power Imbalance Decomposition into Systematic Imbalance and Random Imbalance

    DEFF Research Database (Denmark)

    Kong, Wangwei; Ma, Kang; Wu, Qiuwei

    2017-01-01

    is calculated based on the systematic imbalance component to guide phase swapping. Case studies demonstrate that 72.8% of 782 low voltage substations have systematic imbalance components. The degree of power imbalance results reveal the maximum need for phase swapping and the random imbalance components reveal...

  13. Adjustment of macroeconomic imbalances

    Directory of Open Access Journals (Sweden)

    Georgeta Barbulescu

    2013-03-01

    Full Text Available The global financial and economic crisis was the factor that triggered the adjustment of macroeconomic imbalances accumulated in Romania. The current account deficit and budget deficit were two major structural imbalances that have created a high vulnerability for the economy and explained the extent of economic contraction in Romania during the economic crisis. This article identifies the main causes that lead to the need for fiscal adjustment both in the EU and in Romania, as well as main effects of adjustments in respect of their experience in recent years. The article deals with this topic, because the current topical debate in the field of fiscal adjustments implemented both in the EU and our country, and their need for economic activity aimed at economic recovery.

  14. Insect acid-base physiology.

    Science.gov (United States)

    Harrison, J F

    2001-01-01

    Acid-base status influences many aspects of insect biology, including insect distributions in aquatic systems, insect-plant and insect-pathogen interactions, membrane transport phenomena, and the mode of action of pesticides. Acid-base status in the hemolymph and gut lumen of insects is generally well regulated but varies somewhat within individuals owing to effects of temperature, activity, discontinuous ventilation, and diet. The pH of the midgut lumen varies with the phylogeny and feeding ecology. Insect fluids have buffer values similar to those of vertebrates. The respiratory system participates in acid-base homeostasis primarily by regulating the internal carbon dioxide (partial) pressure via changes in spiracular opening and convective ventilation. The epithelia of the renal system and gut participate in hemolymph acid-base regulation by varying acid-base transport in response to organismal acid-base status. Evidence to date suggests that the dominant mechanisms for control of renal acid-base excretion involve hormonal regulation of H+-V-ATPase activity.

  15. PHYSIOLOGY OF ACID BASE BALANCE

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    Awati

    2014-12-01

    Full Text Available Acid-base, electrolyte, and metabolic disturbances are common in the intensive care unit. Almost all critically ill patients often suffer from compound acid-base and electrolyte disorders. Successful evaluation and management of such patients requires recognition of common patterns (e.g., metabolic acidosis and the ability to dissect one disorder from another. The intensivists needs to identify and correct these condition with the easiest available tools as they are the associated with multiorgan failure. Understanding the elements of normal physiology in these areas is very important so as to diagnose the pathological condition and take adequate measures as early as possible. Arterial blood gas analysis is one such tool for early detection of acid base disorder. Physiology of acid base is complex and here is the attempt to simplify it in our day to day application for the benefit of critically ill patients.

  16. Dijet imbalance in hadronic collisions

    NARCIS (Netherlands)

    Boer, Daniel; Mulders, Piet J.; Pisano, Cristian

    2009-01-01

    The imbalance of dijets produced in hadronic collisions has been used to extract the average transverse momentum of partons inside the hadrons. In this paper we discuss new contributions to the dijet imbalance that could complicate or even hamper this extraction. They are due to polarization of

  17. Chiral imbalance in QCD

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    Andrianov Alexander

    2017-01-01

    Full Text Available The chiral imbalance (ChI is given by a difference between the numbers of RH and LH quarks which may occur in the fireball after heavy ion collision. To characterize it adiabatically a quark chiral (axial chemical potential must be introduced taking into account emergence of a ChI in such a phase. In this report the phenomenology of formation of Local spatial Parity Breaking (LPB in the hot and dense baryon matter is discussed and its simulation within a number of QCD-inspired models is outlined. The appearance of new states in the spectra of scalar, pseudoscalar and vector particles in such a matter is elucidated. In particular, from the effective vector meson theory in the presence of Chern-Simons interaction it is demonstrated that the spectrum of massive vector mesons splits into three polarization components with different effective masses. The asymmetry in production of longitudinally and transversely polarized states of ρ and ω mesons for various values of the dilepton invariant mass can serve as a characteristic indication of the LPB in PHENIX, STAR and ALICE experiments.

  18. [Cancer and electrolytes imbalance].

    Science.gov (United States)

    Shibata, Hiroyuki

    2010-06-01

    The electrolyte imbalance in advanced cancer patients, including hyperkalemia, hypercalcemia and hyponatremia, can be induced by various factors. Hyperkalemia is occasionally induced by chemotherapy for very large malignant tumors, due to tumor lysis syndrome. Hypercalcemia and hyponatremia are often observed in patients with breast cancer, renal cancer, prostate cancer, and the like, as a paraneoplastic syndrome. Some part of hypercalcemia results from osteolysis, but the majority is induced by hormonal factors, such as parathyroid hormone-related protein. One of the paraneoplastic causes of hyponatremia is antidiuretic hormone-producing tumor. These disorders could be morbid or even motile, resulting from encephalopathy or arrhythmia in some cases. However, it should be kept in mind that they could be improved or cured by prompt treatment. Recently, after approval of the molecular targeted drugs for epidermal growth factor receptors, such as cetuximab and panitumumab, the incidence of hypomagnesia with use of these monoclonal antibodies, is relatively frequent. In addition, small molecular targeted drugs, such as m-TORinhibitors and ABL kinase inhibitors, also exert adverse reactions including hypomagnesia and hypophosphatemia. Careful monitoring of the serum concentration of magnesium and phosphate ions, to which little attention was paid previously, is a key issue in these cases.

  19. Chiral imbalance in QCD

    Science.gov (United States)

    Andrianov, Alexander; Andrianov, Vladimir; Espriu, Domenec

    2017-03-01

    The chiral imbalance (ChI) is given by a difference between the numbers of RH and LH quarks which may occur in the fireball after heavy ion collision. To characterize it adiabatically a quark chiral (axial) chemical potential must be introduced taking into account emergence of a ChI in such a phase. In this report the phenomenology of formation of Local spatial Parity Breaking (LPB) in the hot and dense baryon matter is discussed and its simulation within a number of QCD-inspired models is outlined. The appearance of new states in the spectra of scalar, pseudoscalar and vector particles in such a matter is elucidated. In particular, from the effective vector meson theory in the presence of Chern-Simons interaction it is demonstrated that the spectrum of massive vector mesons splits into three polarization components with different effective masses. The asymmetry in production of longitudinally and transversely polarized states of ρ and ω mesons for various values of the dilepton invariant mass can serve as a characteristic indication of the LPB in PHENIX, STAR and ALICE experiments.

  20. Drivers of imbalance cost of wind power

    DEFF Research Database (Denmark)

    Obersteiner, C.; Siewierski, T.; Andersen, Anders

    2010-01-01

    varies in a wide range. To explain differences we indentify parameters influencing imbalance cost and compare them for case studies in Austria, Denmark and Poland. Besides the wind power forecast error also the correlation between imbalance and imbalance price influences imbalance cost significantly....... Especially in systems with significant wind shares, an assessment of imbalance cost based on the amount of imbalance and average System Sell and System Buy Prices is therefore not reliable. While imbalance cost rather reflects cash flows within the clearing of imbalances, the presented concept of cost...... of imperfect forecast is better suited to reflect real cost incurred due to inaccurate wind power forecasts....

  1. Clinical applications of quantitative acid-base chemistry.

    Science.gov (United States)

    Whitehair, K J; Haskins, S C; Whitehair, J G; Pascoe, P J

    1995-01-01

    Stewart used physicochemical principles of aqueous solutions to develop an understanding of variables that control hydrogen ion concentration (H+) in body fluids. He proposed that H+ concentration in body fluids was determined by PCO2, strong ion difference (SID = sum of strong positive ion concentrations minus the sum of the strong anion concentrations) and the total concentration of nonvolatile weak acid (Atot) under normal circumstances. Albumin is the major weak acid in plasma and represents the majority of Atot. These 3 variables were defined as independent variables, which determined the values of all other relevant variables (dependent) in plasma, including H+. The major strong ions in plasma are sodium and chloride. The difference between Na+ and Cl- may be used as an estimation of SID. A decrease in SID below normal results in acidosis (increase in H+) and an increase in SID above normal results in alkalosis (decrease in H+). Unidentified strong anions such as lactate will decrease the SID, if present. Equations developed by Fencl allow Stewart's work to be easily applied clinically for evaluating the metabolic (nonrespiratory) contribution to acid-base balance. This approach separates the net metabolic abnormality into components, and allows one to easily detect mixed metabolic acid-base abnormalities. The Fencl approach provides insight into the nature and severity of the disturbances that exist in the patient. Sodium, chloride, protein, and unidentified anion derangements may contribute to the observed metabolic acid-base imbalance.

  2. Inverse imbalance reconstruction in rotordynamics

    Energy Technology Data Exchange (ETDEWEB)

    Ramlau, R. [Austrian Academy of Sciences, Linz (Austria). Johann Radon Inst. for Computational and Applied Mathematics; Dicken, V. [MeVis GmbH, Bremen (Germany); Maass, P. [Bremen Univ. (Germany). Zentrum fuer Technomathematik; Streller, C. [Rolls-Royce Germany GmbH, Dahlewitz (Germany); Rienaecker, A. [MTU Aero Engines GmbH, Muenchen (Germany)

    2006-05-15

    The goal of this work is to establish and compare algorithms for inverse imbalance reconstruction in aircraft turbines. Such algorithms are based on a validated whole engine model of a turbo engine under consideration. Base on the model, the impact of an imbalance distribution on the vibration behaviour of the turbine can be described as a matrix-vector multiplication Af = g, where f is the imbalance distribution and g the vibration response. It turns out that the matrix A is very ill-conditioned. As the measured data is highly affected with noise, we have to use regularization methods in order to stabilize the inversion. Our main interest was in the use of nonlinear regularization methods, in particular nonlinear filtered singular value decomposition and conjugate gradient regularization. (orig.)

  3. Mobile Clinical Decision Support System for Acid-base Balance Diagnosis and Treatment Recommendation.

    Science.gov (United States)

    Mandzuka, Mensur; Begic, Edin; Boskovic, Dusanka; Begic, Zijo; Masic, Izet

    2017-06-01

    This paper presents mobile application implementing a decision support system for acid-base disorder diagnosis and treatment recommendation. The application was developed using the official integrated development environment for the Android platform (to maximize availability and minimize investments in specialized hardware) called Android Studio. The application identifies disorder, based on the blood gas analysis, evaluates whether the disorder has been compensated, and based on additional input related to electrolyte imbalance, provides recommendations for treatment. The application is a tool in the hands of the user, which provides assistance during acid-base disorders treatment. The application will assist the physician in clinical practice and is focused on the treatment in intensive care.

  4. TARGET Imbalances at Record Levels

    DEFF Research Database (Denmark)

    Hallett, Andrew Hughes

    TARGET is the payments system for making settlements between euro area economies and five other EU economies. Cross-border transactions generate claims/surpluses and liabilities/deficits among national central banks which “net out” for the system as a whole. These imbalances are manageable in rel...

  5. Gender imbalance in secondary schools

    Directory of Open Access Journals (Sweden)

    Catherine Howgego Mugisha

    2005-01-01

    Full Text Available Significantly fewer girls than boys attend schools inrefugee camps. As the level of education increases, there is a corresponding decrease in the numbers of female participants. This has resulted in a severe gender imbalance in refugee secondary schools.

  6. Modelling of acid-base equilibria.

    Science.gov (United States)

    Jabor, A; Kazda, A

    1995-01-01

    A quantitative evaluation of metabolic acid-base component is described. The model is based on Stewart's analysis of acid-base chemistry. The metabolic component of acid-base disturbances is divided into four partial metabolic disorders; they can result from abnormal concentrations of chloride, albumin and phosphate disturbances, or from appearance of abnormal unidentified strong anions. The efficiency of the model is sufficient, quantitative partial results are given in the same units as base excess. In complex acid-base disturbances, such as are seen in critically ill patients, a detailed analysis of the specific components of the metabolic acid-base status allows one to plan specific therapeutic interventions.

  7. Acid-base disorders in liver disease.

    Science.gov (United States)

    Scheiner, Bernhard; Lindner, Gregor; Reiberger, Thomas; Schneeweiss, Bruno; Trauner, Michael; Zauner, Christian; Funk, Georg-Christian

    2017-11-01

    Alongside the kidneys and lungs, the liver has been recognised as an important regulator of acid-base homeostasis. While respiratory alkalosis is the most common acid-base disorder in chronic liver disease, various complex metabolic acid-base disorders may occur with liver dysfunction. While the standard variables of acid-base equilibrium, such as pH and overall base excess, often fail to unmask the underlying cause of acid-base disorders, the physical-chemical acid-base model provides a more in-depth pathophysiological assessment for clinical judgement of acid-base disorders, in patients with liver diseases. Patients with stable chronic liver disease have several offsetting acidifying and alkalinising metabolic acid-base disorders. Hypoalbuminaemic alkalosis is counteracted by hyperchloraemic and dilutional acidosis, resulting in a normal overall base excess. When patients with liver cirrhosis become critically ill (e.g., because of sepsis or bleeding), this fragile equilibrium often tilts towards metabolic acidosis, which is attributed to lactic acidosis and acidosis due to a rise in unmeasured anions. Interestingly, even though patients with acute liver failure show significantly elevated lactate levels, often, no overt acid-base disorder can be found because of the offsetting hypoalbuminaemic alkalosis. In conclusion, patients with liver diseases may have multiple co-existing metabolic acid-base abnormalities. Thus, knowledge of the pathophysiological and diagnostic concepts of acid-base disturbances in patients with liver disease is critical for therapeutic decision making. Copyright © 2017 European Association for the Study of the Liver. Published by Elsevier B.V. All rights reserved.

  8. Nutrient imbalance in Norway spruce

    Energy Technology Data Exchange (ETDEWEB)

    Thelin, Gunnar

    2000-11-01

    The studies presented in my thesis indicate that growing Norway spruce in monoculture does not constitute sustainable forest management in a high N and S deposition environment, such as in southern Sweden. The combination of N-induced high growth rates and leaching due to soil acidification causes soil reserves of nutrients to decrease. This will increase the risk of nutrient imbalance within the trees when nutrient demands are not met. The development of nutrient imbalance in Scania, southern Sweden, was shown as negative trends in needle and soil nutrient status from the mid-80s to the present in Norway spruce and Scots pine stands. This imbalance appears to be connected to high levels of N and S deposition. Clear negative effects on tree vitality were found when using a new branch development method. Today, growth and vitality seems to be limited by K, rather than N, in spruce stands older than 40 years. However, younger stands appear to be able to absorb the deposited N without negative effects on growth and vitality. When investigating effects of nutrient stress on tree vitality, indicators such as branch length and shoot multiplication rate, which include effects accumulated over several years, are suitable. Countermeasures are needed in order to maintain the forest production at a high level. Positive effects on tree nutrient status after vitality fertilization (N-free fertilization) was shown in two micronutrient deficient stands in south-central Sweden. In addition, tree vitality was positively affected after the application of a site-adapted fertilizer to the canopy. Site-adaption of fertilizers will most likely improve the possibilities of a positive response on tree growth and vitality in declining stands. In a survey of Norway spruce in mixtures with beech, birch, or oak compared to monocultures it was shown that spruce nutrient status was higher in mixtures with deciduous species than in monocultures. By using mixed-species stands the need for

  9. The Kidney and Acid-Base Regulation

    Science.gov (United States)

    Koeppen, Bruce M.

    2009-01-01

    Since the topic of the role of the kidneys in the regulation of acid base balance was last reviewed from a teaching perspective (Koeppen BM. Renal regulation of acid-base balance. Adv Physiol Educ 20: 132-141, 1998), our understanding of the specific membrane transporters involved in H+, HCO , and NH transport, and especially how these…

  10. Adult Spinal Deformity: Sagittal Imbalance

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    Cavanilles-Walker JM

    2014-10-01

    Full Text Available Spinal sagittal imbalance, deformity of the spine in the sagittal plane, is nowadays a major cause of pain and disability among patients presenting to the spine clinic in daily practice. Normal sagittal spinal balance is a result of mutual articulation of the pelvis and the spine in the sagittal plane. Sagittal imbalance of the spine could be related to many spinal pathologies interesting primarily the spine or could appear after an instrumentation spinal surgery. Variations in the spine sagittal alignment can be compensated by compensatory mechanisms occurring in the spine, pelvis and lower limb areas. The main objective of these mechanisms is to allow the patient to keep an erect position within the cone of economy in an energy-efficient way. Once a spinal deformity surpasses these compensatory mechanisms surgical intervention is often requested. In this paper the Authors performed comprehensive a critical analysis of the rigidity of the deformity, including the spinal and pelvic parameters. The compensatory mechanisms are paramount in order to be able to offer a tailored solution to these patients. Since conservative measures fail in most patients, successful management of these patients requires achieving fusion of a balanced spine. Appropriate preoperative optimization as well as appropriate surgical preoperative planning are critical in order to avoid potential complications. Selecting the appropriate surgical technique to achieve spinal balance is crucial to success.

  11. Aggregate savings and external imbalances in China

    OpenAIRE

    Yang, Dennis Tao

    2012-01-01

    Over the last decade, the internal and external macroeconomic imbalances in China have risen to unprecedented levels. In 2008, China's national savings rate soared to over 53 percent of its GDP, whereas its current account surplus exceeded 9 percent of GDP. This paper presents a unified framework for understanding the structural causes of these imbalances. I argue that the imbalances are attributable to a set of policies and institutions embedded in the economy. I propose a unified framework ...

  12. Energy Imbalance Markets (Fact Sheet)

    Energy Technology Data Exchange (ETDEWEB)

    2012-09-01

    The anticipated increase in variable renewable generation, such as wind and solar power, over the next several years has raised concerns about how system operators will maintain balance between electricity production and demand in the Western Interconnection, especially in its smaller balancing authority areas (BAAs). Given renewable portfolio standards in the West, it is possible that more than 50 gigawatts of wind capacity will be installed by 2020. Significant quantities of solar generation are likely to be added as well. Meanwhile, uncertainties about future load growth and challenges siting new transmission and generation resources may add additional stresses on the Western Interconnection of the future. One proposed method of addressing these challenges is an energy imbalance market (EIM). An EIM is a means of supplying and dispatching electricity to balance fluctuations in generation and load. It aggregates the variability of generation and load over multiple balancing areas (BAs).

  13. Gender Imbalance and Terrorism in Developing Countries.

    Science.gov (United States)

    Younas, Javed; Sandler, Todd

    2017-03-01

    This article investigates whether gender imbalance may be conducive to domestic terrorism in developing countries. A female-dominated society may not provide sufficient administration, law, or order to limit domestic terrorism, especially since societies in developing countries primarily turn to males for administration, policing, and paramilitary forces. Other economic considerations support female imbalance resulting in grievance-generated terrorism. Because male dominance may also be linked to terrorism, empirical tests are ultimately needed to support our prediction. Based on panel data for 128 developing countries for 1975 to 2011, we find that female gender imbalance results in more total and domestic terrorist attacks. This female gender imbalance does not affect transnational terrorism in developing countries or domestic and transnational terrorism in developed countries. Further tests show that gender imbalance affects terrorism only when bureaucratic institutions are weak. Many robustness tests support our results.

  14. Earth's energy imbalance and implications

    Directory of Open Access Journals (Sweden)

    J. Hansen

    2011-12-01

    Full Text Available Improving observations of ocean heat content show that Earth is absorbing more energy from the Sun than it is radiating to space as heat, even during the recent solar minimum. The inferred planetary energy imbalance, 0.58 ± 0.15 W m−2 during the 6-yr period 2005–2010, confirms the dominant role of the human-made greenhouse effect in driving global climate change. Observed surface temperature change and ocean heat gain together constrain the net climate forcing and ocean mixing rates. We conclude that most climate models mix heat too efficiently into the deep ocean and as a result underestimate the negative forcing by human-made aerosols. Aerosol climate forcing today is inferred to be −1.6 ± 0.3 W m−2, implying substantial aerosol indirect climate forcing via cloud changes. Continued failure to quantify the specific origins of this large forcing is untenable, as knowledge of changing aerosol effects is needed to understand future climate change. We conclude that recent slowdown of ocean heat uptake was caused by a delayed rebound effect from Mount Pinatubo aerosols and a deep prolonged solar minimum. Observed sea level rise during the Argo float era is readily accounted for by ice melt and ocean thermal expansion, but the ascendency of ice melt leads us to anticipate acceleration of the rate of sea level rise this decade.

  15. [Kidney, Fluid, and Acid-Base Balance].

    Science.gov (United States)

    Shioji, Naohiro; Hayashi, Masao; Morimatsu, Hiroshi

    2016-05-01

    Kidneys play an important role to maintain human homeostasis. They contribute to maintain body fluid, electrolytes, and acid-base balance. Especially in fluid control, we, physicians can intervene body fluid balance using fluid resuscitation and diuretics. In recent years, one type of fluid resuscitation, hydroxyl ethyl starch has been extensively studied in the field of intensive care. Although their effects on fluid resuscitation are reasonable, serious complications such as kidney injury requiring renal replacement therapy occur frequently. Now we have to pay more attention to this important complication. Another topic of fluid management is tolvaptan, a selective vasopressin-2 receptor antagonist Recent randomized trial suggested that tolvaptan has a similar supportive effect for fluid control and more cost effective compared to carperitide. In recent years, Stewart approach is recognized as one important tool to assess acid-base balance in critically ill patients. This approach has great value, especially to understand metabolic components in acid-base balance. Even for assessing the effects of kidneys on acid-base balance, this approach gives us interesting insight. We should appropriately use this new approach to treat acid-base abnormality in critically ill patients.

  16. Hypokalemic paralysis and acid-base balance

    Directory of Open Access Journals (Sweden)

    Ivo Casagranda

    2006-10-01

    Full Text Available Three cases of hypokalemic paralysis are reported, presenting to the Emergency Department. The first is a patient with a hypokalemic periodic paralysis with a normal acid-base status, the second is a case of hypokalemic flaccid paralysis of all extremities with a normal anion gap metabolic acidosis, the last is a patient with a hypokalemic distal paralysis of right upper arm with metabolic alkalosis. Afterwards some pathophysiologic principles and the clinical aspects of hypokalemia are discussed and an appropriate approach to do in Emergency Department, to identify the hypokalemic paralysis etiologies in the Emergency Department, is presented, beginning from the evaluation of acid-base status.

  17. Glycine/Glycolic acid based copolymers

    NARCIS (Netherlands)

    in 't Veld, P.J.A.; in 't Veld, Peter J.A.; Shen, Zheng-Rong; Shen, Z.; Takens, Gijsbert A.J.; Takens, G.A.J.; Dijkstra, Pieter J.; Feijen, Jan

    1994-01-01

    Glycine/glycolic acid based biodegradable copolymers have been prepared by ring-opening homopolymerization of morpholine-2,5-dione, and ring-opening copolymerization of morpholine-2,5-dione and glycolide. The homopolymerization of morpholine-2,5-dione was carried out in the melt at 200°C for 3 min

  18. Jigsaw Cooperative Learning: Acid-Base Theories

    Science.gov (United States)

    Tarhan, Leman; Sesen, Burcin Acar

    2012-01-01

    This study focused on investigating the effectiveness of jigsaw cooperative learning instruction on first-year undergraduates' understanding of acid-base theories. Undergraduates' opinions about jigsaw cooperative learning instruction were also investigated. The participants of this study were 38 first-year undergraduates in chemistry education…

  19. Separation of Acids, Bases, and Neutral Compounds

    Science.gov (United States)

    Fujita, Megumi; Mah, Helen M.; Sgarbi, Paulo W. M.; Lall, Manjinder S.; Ly, Tai Wei; Browne, Lois M.

    2003-01-01

    Separation of Acids, Bases, and Neutral Compounds requires the following software, which is available for free download from the Internet: Netscape Navigator, version 4.75 or higher, or Microsoft Internet Explorer, version 5.0 or higher; Chime plug-in, version compatible with your OS and browser (available from MDL); and Flash player, version 5 or higher (available from Macromedia).

  20. Trunk imbalance in adolescent idiopathic scoliosis.

    Science.gov (United States)

    Fortin, Carole; Grunstein, Erin; Labelle, Hubert; Parent, Stefan; Ehrmann Feldman, Debbie

    2016-06-01

    Trunk imbalance (ie, frontal trunk shift measured with a plumb line from C7 to S1) is part of the clinical evaluation in adolescent idiopathic scoliosis (AIS), but its prevalence and relationship with scoliosis, back pain, and health-related factors are not well documented. The principal objectives are to document trunk imbalance prevalence and to explore the association between trunk imbalance and the following factors: Cobb angle, type of scoliosis, back pain, function, mental health, and self-image. The secondary objective is to determine back pain prevalence and the relationship between back pain and each of the following: Cobb angle, function, mental health, and self-image. This is a cross-sectional study in a scoliosis clinic of a tertiary university hospital center. The sample includes youth with AIS (N=55). The outcome measures were trunk imbalance prevalence and magnitude, and back pain prevalence and intensity using the Numeric Pain Rating Scale (NPRS) and the Scoliosis Research Society-22 (SRS-22) pain score, and the function, self-image, and mental health domains of the SRS-22. Trunk imbalance and back pain were assessed in 55 patients with AIS (Cobb angle: 10-60°). Patients completed the SRS-22 questionnaire and the NPRS. Correlations were done between trunk imbalance and scoliosis (Cobb angle, type of scoliosis), back pain (NPRS and SRS-22 pain score), and health-related factors using Pearson correlation coefficients (r) and logistic regression models. Trunk imbalance prevalence is 85% and back pain prevalence is 73%. We found fair to moderate significant positive correlation between trunk imbalance and Cobb angle (r=0.32-0.66, pscoliosis. Lower self-reported pain significantly correlated with lower Cobb angles (r=0.29, p=.03), higher function (r=0.55, p=.000), higher self-image (r=0.44, p=.001), and better mental health (r=0.48, p=.000). There was a trend for trunk imbalance to be related with lower pain in logistic regression models. The high

  1. Acid-base balance in lake water

    Energy Technology Data Exchange (ETDEWEB)

    Brosset, C.

    1980-02-01

    As expected, the acid-base content of lake water is composed of strong base or acid, weak acids (mainly fulvic acid) and carbonic acid. All of these may be determined by using a simple titration method. The concentration of undissociated carbonic acid sometimes appears not to be in equilibrium with the CO/sub 2/-concentration in air. Observed supersaturation seems to be connected to the concentration of fulvic acid.

  2. Gene dosage imbalances: action, reaction, and models.

    Science.gov (United States)

    Veitia, Reiner A; Potier, Marie Claude

    2015-06-01

    Single-gene deletions, duplications, and misregulation, as well as aneuploidy, can lead to stoichiometric imbalances within macromolecular complexes and cellular networks, causing their malfunction. Such alterations can be responsible for inherited or somatic genetic disorders including Mendelian diseases, aneuploid syndromes, and cancer. We review the effects of gene dosage alterations at the transcriptomic and proteomic levels, and the various responses of the cell to counteract their effects. Furthermore, we explore several biochemical models and ideas that can provide the rationale for treatments modulating the effects of gene dosage imbalances. Copyright © 2015 Elsevier Ltd. All rights reserved.

  3. The Hegelian dialectics of global imbalances

    Directory of Open Access Journals (Sweden)

    Célestin Monga

    2012-11-01

    Full Text Available Traditional narratives of external imbalances have focused on the analysis of national accounts, trade flows, and financial flows. They have generated two opposing views of the current situation of the world economy: on one side, a prudent, if not pessimistic view considers large imbalances as evidence of problems with the international monetary and financial system, and symptoms of domestic distortions (mainly in the United States and China. On the other side, a relaxed, if not optimistic view suggests that global imbalances are not anomalies but simply the predictable outcome of a world with increasingly globalized financial flows in search of the right mix of risks and returns. This paper offers a critical analysis of these competing explanations of the United States-China imbalances and suggests a way of reconciling them. The paper uses Hegel’s parable of the development of self-consciousness to explain the dynamics between the two countries. Hegel may not have been a great philosopher of history but his study of lordship and bondage provides a good framework for analyzing the dialectics of recognition and acknowledgement that currently characterizes the macroeconomic relationships between the United States and China.

  4. Analysis of Levene's Test under Design Imbalance.

    Science.gov (United States)

    Keyes, Tim K.; Levy, Martin S.

    1997-01-01

    H. Levene (1960) proposed a heuristic test for heteroscedasticity in the case of a balanced two-way layout, based on analysis of variance of absolute residuals. Conditions under which design imbalance affects the test's characteristics are identified, and a simple correction involving leverage is proposed. (SLD)

  5. Investigating Students' Reasoning about Acid-Base Reactions

    Science.gov (United States)

    Cooper, Melanie M.; Kouyoumdjian, Hovig; Underwood, Sonia M.

    2016-01-01

    Acid-base chemistry is central to a wide range of reactions. If students are able to understand how and why acid-base reactions occur, it should provide a basis for reasoning about a host of other reactions. Here, we report the development of a method to characterize student reasoning about acid-base reactions based on their description of…

  6. Assessing College Students' Understanding of Acid Base Chemistry Concepts

    Science.gov (United States)

    Wan, Yanjun Jean

    2014-01-01

    Typically most college curricula include three acid base models: Arrhenius', Bronsted-Lowry's, and Lewis'. Although Lewis' acid base model is generally thought to be the most sophisticated among these three models, and can be further applied in reaction mechanisms, most general chemistry curricula either do not include Lewis' acid base model, or…

  7. Using Willie's Acid-Base Box for Blood Gas Analysis

    Science.gov (United States)

    Dietz, John R.

    2011-01-01

    In this article, the author describes a method developed by Dr. William T. Lipscomb for teaching blood gas analysis of acid-base status and provides three examples using Willie's acid-base box. Willie's acid-base box is constructed using three of the parameters of standard arterial blood gas analysis: (1) pH; (2) bicarbonate; and (3) CO[subscript…

  8. Teaching Acid/Base Physiology in the Laboratory

    Science.gov (United States)

    Friis, Ulla G.; Plovsing, Ronni; Hansen, Klaus; Laursen, Bent G.; Wallstedt, Birgitta

    2010-01-01

    Acid/base homeostasis is one of the most difficult subdisciplines of physiology for medical students to master. A different approach, where theory and practice are linked, might help students develop a deeper understanding of acid/base homeostasis. We therefore set out to develop a laboratory exercise in acid/base physiology that would provide…

  9. Changes in the acid-base balance and lactate concentration in the blood in amateur ultramarathon runners during a 100-km run.

    Science.gov (United States)

    Jastrzębski, Z; Żychowska, M; Konieczna, A; Ratkowski, W; Radzimiński, Ł

    2015-09-01

    The aim of this study was to analyse the acid-base balance and partial pressure of blood gases of participants during a 100-km run. Fourteen experienced amateur ultramarathon runners (age: 43.36±11.83 years; height: 175.29±6.98 cm; weight: 72.12±7.36 kg) completed the 100-km run. Blood samples were taken before the run; after 25, 50, 75, and 100 km; and 12 and 24 hours after the run. There were significant differences (pamateurs runners are able to adjust their running speed so as not to provoke a significant acid-base imbalance or lactate acid accumulation.

  10. Education in the imbalance of Nature

    Science.gov (United States)

    Shlafman, L. M.; Kontar, V. A.

    2013-12-01

    There are two concepts understanding of the real Nature: balanced and imbalanced. The traditional balanced concept understanding of Nature was originated in prehistoric times to calm the frightened souls of prehistoric man and manage groups of people. The balanced concept presupposes that Nature is isotropic, balanced, etc. The balanced concept of understanding of Nature gradually has moved to science and technology. The balanced concept of understanding of Nature is dominating from the prehistoric time up to today. But always parallel and opposite was exists the concept imbalanced understanding of Nature, which presupposes that Nature is anisotropy, imbalanced, etc. The balanced concept is much simpler than Imbalanced. The balanced concept has given mankind a lot of rough description of Nature which helped to solve a lot of practical problems but with sufficient accuracy, i.e. approximately, but not with an absolute precision. While people were few, and a lot of resources, person could take from Nature only what Nature gave willingly. During this period, people feared and respected Nature and Nature was able easily compensate the activity of people. The high accuracy of the description of Nature was not needed when resources were plentiful and people were few. But now the situation is completely different. The population has become a very large and growing. Traditional resources are almost run out and the lack of resources escalates. People are not afraid of Nature and bravely try to take by force what Nature does not give voluntarily. People invaded into imbalance Nature, and Nature can no longer compensate activity of people. The era of global change is started, including those that man provokes. In the conditions of global changes is insufficiently of the approximate solutions of the traditional balanced concept. The balanced concept is exhausted, and increasingly misleads people. The balanced concept cannot solve the problems that arise in the global change

  11. Bedside Analysis of Acid-Base Balance

    Directory of Open Access Journals (Sweden)

    Yu. S. Podlesskikh

    2006-01-01

    Full Text Available Laboratory service is one of the most hang-the-expense items in the cost of treatment of patients in an intensive care unit. Isolated acid-base balance (ABB impairments are rare in clinical practice. These impairments are generally combined and they frequently cause a drastic change in the pH value of blood. Early detection of their origin and its elimination are of profound importance in these situations. Miniaturization of analyzers has made it possible to conduct some investigations and particularly to determine ABB just in the intensive care unit or operating suite. The attached software permits creation of a database and transmission of information to the laboratory network. One year’s experience has indicated that the quality of reagents and reference substances allows real-time determination of the values of ABB with a high degree of accuracy and reproducibility at a patient’s bed. 

  12. Electrical properties of nucleic acid bases

    Science.gov (United States)

    Basch, Harold; Garmer, D. R.; Jasien, P. G.; Krauss, M.; Stevens, W. J.

    1989-11-01

    The dipole polarizabilities for the five nucleic acid bases, uracil, cytosine, thymine, guanine, and adenine have been determined by the coupled perturbed Hartree-Fock (CPHF) method using a polarized double-zeta basis set. Electronic correlation corrections from second-order Møller-Plesset (MP2) perturbation theory are given. The treatment required to obtain accurate polarizabilities of these π systems was estimated from calculations on imidazole, benzene, and pyridine, giving results that are in good agreement with experiment. Similarly, optimal basis sets for static electrical properties were determined and applied to calculations of the dipole moments of the bases. With correlation corrections, these agree with experiment within 5% for all molecules except adenine.

  13. Electrolyte Imbalance in Patients with Sheehan's Syndrome

    OpenAIRE

    Chur Hoan Lim; Ji Hyun Han; Joon Jin; Ji Eun Yu; Jin Ook Chung; Dong Hyeok Cho; Dong Jin Chung; Min Young Chung

    2015-01-01

    Background We investigated the prevalence of electrolyte imbalance and the relationship between serum electrolyte and anterior pituitary hormone levels in patients with Sheehan's syndrome. Methods In a retrospective study, we investigated 78 patients with Sheehan's syndrome. We also included 95 normal control subjects who underwent a combined anterior pituitary hormone stimulation test and showed normal hormonal responses. Results In patients with Sheehan's syndrome, the serum levels of sodiu...

  14. Financial Imbalances and Macro-prudential Policies

    Directory of Open Access Journals (Sweden)

    Polikarpova Olga S.

    2015-11-01

    Full Text Available The credit crisis and its transformation into a sovereign debt crisis have illustrated the limited character of the traditional macro financial politics. The financial crisis has shown that the priority of price stability does not guarantee macroeconomic stability. Revision of the goals and objectives of the monetary and credit policy is being carried out in many countries. In order to ensure macroeconomic stability, central banks have to use new instruments considering financial stability as an additional object. Since 2009 the IMF recommends central banks to use macro-prudential instruments for reducing macro-financial risks and imbalances in the financial system structure. The effectiveness of macro-prudential policy depends on its calibration with the monetary and credit policy. The growth of financial imbalances in the first decade after the adoption of the euro, presence of contradictory fiscal policies, deployment of a spiral of rapid crediting and price inflation have led to apraxia in the monetary and credit policy, and fiscal policy was limited by institutional arrangements. Accumulating funds during the budget surplus the countries-members of the European Monetary System (EMS attempted to reduce asymmetric shocks. The priority of price stability in the EMS had been achieved but the economies of these countries suffered from financial imbalances. Macro-prudential policy is aimed at prevention and mitigation of systemic risk, plays a significant role in reforming the new policy of central banks. That is why European countries are developing new methods and an institutional framework for the implementation of a new macro-prudential policy. Problems of structural arbitration and the possibility of emergence of new financial imbalances in the EMS are becoming increasingly real. The flow of financial capitals and financial institutions to more lenient jurisdictions is connected with the establishment of macro-prudential policy. The macro

  15. The Global Imbalance of the Inanimate Nature

    Science.gov (United States)

    Vargashkin, V. Y.

    2013-12-01

    The preservation laws serve is the general expression of balancing properties and stability in nature. The preservation laws, according to Noether's theorem, are displays of properties of uniformity and isotropy of space and time. So, in the most global representation, the imbalance of the Universe assumes presence of some large-scale non-uniformity in it. The scale of such non-uniformity may form the basis for balance and imbalance correlation in the nature as a whole. This heterogeneity may lead to global infringement of laws of preservation, such as laws of preservation of an impulse, the impulse and the moment of energy. So, the most global imbalance of the inanimate nature may be connected with existence of large-scale fluctuations of properties of the Universe matter. It is possible to think about existence of such imbalance with presence of the allocated areas and directions on celestial sphere. Now most of interest in a science is represented by some types of global anisotropy. First, it is spatial anisotropy of cosmic microwave background. It depends of direction on celestial sphere, including formation of the allocated directions, and also "hot" and "cold" spots. Secondly, it is anisotropy of substance's density, concerning clusters and super clusters of galaxies. It is known as a large-scale structure of the Universe. This kind of anisotropy is connected with imbalance between distributions of radiated substance and observable emptiness. The geometry of this kind of imbalance is that the shining matter forms "cellular", "sheet" or "filaments" structure, forming the cells, filled with visible "voids". Thirdly, it is the hypothetical anisotropy connected with prospective dependence of speed of expansion of the Universe with direction on celestial sphere, and also with time. The relative size for this speed is known as Hubble's parameter. The told testifies about actuality of systematization, and also revelation of an interconnection and mutual

  16. Power-law tails in the distribution of order imbalance

    Science.gov (United States)

    Zhang, Ting; Gu, Gao-Feng; Xu, Hai-Chuan; Xiong, Xiong; Chen, Wei; Zhou, Wei-Xing

    2017-10-01

    We investigate the probability distribution of order imbalance calculated from the order flow data of 43 Chinese stocks traded on the Shenzhen Stock Exchange. Two definitions of order imbalance are considered based on the order number and the order size. We find that the order imbalance distributions of individual stocks have power-law tails. However, the tail index fluctuates remarkably from stock to stock. We also investigate the distributions of aggregated order imbalance of all stocks at different timescales Δt. We find no clear trend in the tail index with respect Δt. All the analyses suggest that the distributions of order imbalance are asymmetric.

  17. Deoxyribonucleic Acid Base Composition in Yeasts

    Science.gov (United States)

    Meyer, Sally A.; Phaff, H. J.

    1969-01-01

    The deoxyribonucleic acid base composition of 15 species of yeasts was determined to obtain further clues to or supporting evidence for their taxonomic position. Species examined belonged to the genera Saccharomyces, Debaryomyces, Lodderomyces, Metschnikowia, and Candida. The range of moles per cent guanine plus cytosine (GC content) for all yeasts examined extended from 34.9 to 48.3%. The sporogenous species and the asporogenous yeasts spanned the range with 36.6 to 48.3% GC and 34.9 to 48% GC, respectively. Three Saccharomyces species (S. rosei and related species) exhibited significantly higher GC contents than S. cerevisiae, whereas the fermentative species D. globosus revealed a%GC more aligned to the S. rosei group than to the nonfermentative D. hansenii. Similar GC contents were demonstrated by L. elongasporus and its proposed imperfect form C. parapsilosis. The range of GC contents of various strains of three Metschnikowia species studied was 6.1%, with the type strain of M. pulcherrima having the highest GC content (48.3%) of all of the yeasts examined. PMID:5764346

  18. Effects of gas exchange on acid-base balance.

    Science.gov (United States)

    Lindinger, Michael I; Heigenhauser, George J F

    2012-07-01

    This paper describes the interactions between ventilation and acid-base balance under a variety of conditions including rest, exercise, altitude, pregnancy, and various muscle, respiratory, cardiac, and renal pathologies. We introduce the physicochemical approach to assessing acid-base status and demonstrate how this approach can be used to quantify the origins of acid-base disorders using examples from the literature. The relationships between chemoreceptor and metaboreceptor control of ventilation and acid-base balance summarized here for adults, youth, and in various pathological conditions. There is a dynamic interplay between disturbances in acid-base balance, that is, exercise, that affect ventilation as well as imposed or pathological disturbances of ventilation that affect acid-base balance. Interactions between ventilation and acid-base balance are highlighted for moderate- to high-intensity exercise, altitude, induced acidosis and alkalosis, pregnancy, obesity, and some pathological conditions. In many situations, complete acid-base data are lacking, indicating a need for further research aimed at elucidating mechanistic bases for relationships between alterations in acid-base state and the ventilatory responses. 2012 American Physiological Society. Compr Physiol 2:2037-2061, 2012.

  19. Acid-base physiology, neurobiology and behaviour in relation to CO2-induced ocean acidification.

    Science.gov (United States)

    Tresguerres, Martin; Hamilton, Trevor J

    2017-06-15

    Experimental exposure to ocean and freshwater acidification affects the behaviour of multiple aquatic organisms in laboratory tests. One proposed cause involves an imbalance in plasma chloride and bicarbonate ion concentrations as a result of acid-base regulation, causing the reversal of ionic fluxes through GABA A receptors, which leads to altered neuronal function. This model is exclusively based on differential effects of the GABA A receptor antagonist gabazine on control animals and those exposed to elevated CO 2 However, direct measurements of actual chloride and bicarbonate concentrations in neurons and their extracellular fluids and of GABA A receptor properties in aquatic organisms are largely lacking. Similarly, very little is known about potential compensatory mechanisms, and about alternative mechanisms that might lead to ocean acidification-induced behavioural changes. This article reviews the current knowledge on acid-base physiology, neurobiology, pharmacology and behaviour in relation to marine CO 2 -induced acidification, and identifies important topics for future research that will help us to understand the potential effects of predicted levels of aquatic acidification on organisms. © 2017. Published by The Company of Biologists Ltd.

  20. Impact of the diet on net endogenous acid production and acid-base balance.

    Science.gov (United States)

    Poupin, Nathalie; Calvez, Juliane; Lassale, Camille; Chesneau, Caroline; Tomé, Daniel

    2012-06-01

    Net acid production, which is composed of volatile acids (15,000 mEq/day) and metabolic acids (70-100 mEq/day) is relatively small compared to whole-body H⁺ turnover (150,000 mEq/day). Metabolic acids are ingested from the diet or produced as intermediary or end products of endogenous metabolism. The three commonly reported sources of net acid production are the metabolism of sulphur amino acids, the metabolism or ingestion of organic acids, and the metabolism of phosphate esters or dietary phosphoproteins. Net base production occurs mainly as a result of absorption of organic anions from the diet. To maintain acid-base balance, ingested and endogenously produced acids are neutralized within the body by buffer systems or eliminated from the body through the respiratory (excretion of volatile acid in the form of CO₂) and urinary (excretion of fixed acids and remaining H⁺) pathways. Because of the many reactions involved in the acid-base balance, the direct determination of acid production is complex and is usually estimated through direct or indirect measurements of acid excretion. However, indirect approaches, which assess the acid-forming potential of the ingested diet based on its composition, do not take all the acid-producing reactions into account. Direct measurements therefore seem more reliable. Nevertheless, acid excretion does not truly provide information on the way acidity is dealt with in the plasma and this measurement should be interpreted with caution when assessing acid-base imbalance. Copyright © 2012 Elsevier Ltd and European Society for Clinical Nutrition and Metabolism. All rights reserved.

  1. Electrolyte Imbalance in Patients with Sheehan's Syndrome

    Directory of Open Access Journals (Sweden)

    Chur Hoan Lim

    2015-12-01

    Full Text Available BackgroundWe investigated the prevalence of electrolyte imbalance and the relationship between serum electrolyte and anterior pituitary hormone levels in patients with Sheehan's syndrome.MethodsIn a retrospective study, we investigated 78 patients with Sheehan's syndrome. We also included 95 normal control subjects who underwent a combined anterior pituitary hormone stimulation test and showed normal hormonal responses.ResultsIn patients with Sheehan's syndrome, the serum levels of sodium, potassium, ionized calcium, magnesium, and inorganic phosphate were significantly lower than those in control subjects. The prevalence of hyponatremia, hypokalemia, hypocalcemia, hypomagnesemia, and hypophosphatemia in patients with Sheehan's syndrome was 59.0% (n=46, 26.9% (n=21, 35.9% (n=28, 47.4% (n=37, and 23.1% (n=18, respectively. Levels of sodium and ionized calcium in serum were positively correlated with levels of all anterior pituitary hormones (all P<0.05. Levels of potassium in serum were positively correlated with adrenocorticotrophic hormone (ACTH and growth hormone (GH levels (all P<0.05. Levels of inorganic phosphate in serum were positively correlated with levels of thyroid-stimulating hormone, prolactin, and GH (all P<0.05, and levels of magnesium in serum were positively correlated with delta ACTH (P<0.01.ConclusionElectrolyte imbalance was common in patients with Sheehan's syndrome. Furthermore, the degree of anterior pituitary hormone deficiency relates to the degree of electrolyte disturbance in patients with this disease.

  2. Electrolyte Imbalance in Patients with Sheehan's Syndrome.

    Science.gov (United States)

    Lim, Chur Hoan; Han, Ji Hyun; Jin, Joon; Yu, Ji Eun; Chung, Jin Ook; Cho, Dong Hyeok; Chung, Dong Jin; Chung, Min Young

    2015-12-01

    We investigated the prevalence of electrolyte imbalance and the relationship between serum electrolyte and anterior pituitary hormone levels in patients with Sheehan's syndrome. In a retrospective study, we investigated 78 patients with Sheehan's syndrome. We also included 95 normal control subjects who underwent a combined anterior pituitary hormone stimulation test and showed normal hormonal responses. In patients with Sheehan's syndrome, the serum levels of sodium, potassium, ionized calcium, magnesium, and inorganic phosphate were significantly lower than those in control subjects. The prevalence of hyponatremia, hypokalemia, hypocalcemia, hypomagnesemia, and hypophosphatemia in patients with Sheehan's syndrome was 59.0% (n=46), 26.9% (n=21), 35.9% (n=28), 47.4% (n=37), and 23.1% (n=18), respectively. Levels of sodium and ionized calcium in serum were positively correlated with levels of all anterior pituitary hormones (all PElectrolyte imbalance was common in patients with Sheehan's syndrome. Furthermore, the degree of anterior pituitary hormone deficiency relates to the degree of electrolyte disturbance in patients with this disease.

  3. Primer on clinical acid-base problem solving.

    Science.gov (United States)

    Whittier, William L; Rutecki, Gregory W

    2004-03-01

    Acid-base problem solving has been an integral part of medical practice in recent generations. Diseases discovered in the last 30-plus years, for example, Bartter syndrome and Gitelman syndrome, D-lactic acidosis, and bulimia nervosa, can be diagnosed according to characteristic acid-base findings. Accuracy in acid-base problem solving is a direct result of a reproducible, systematic approach to arterial pH, partial pressure of carbon dioxide, bicarbonate concentration, and electrolytes. The 'Rules of Five' is one tool that enables clinicians to determine the cause of simple and complex disorders, even triple acid-base disturbances, with consistency. In addition, other electrolyte abnormalities that accompany acid-base disorders, such as hypokalemia, can be incorporated into algorithms that complement the Rules and contribute to efficient problem solving in a wide variety of diseases. Recently urine electrolytes have also assisted clinicians in further characterizing select disturbances. Acid-base patterns, in many ways, can serve as a 'common diagnostic pathway' shared by all subspecialties in medicine. From infectious disease (eg, lactic acidemia with highly active antiviral therapy therapy) through endocrinology (eg, Conn's syndrome, high urine chloride alkalemia) to the interface between primary care and psychiatry (eg, bulimia nervosa with multiple potential acid-base disturbances), acid-base problem solving is the key to unlocking otherwise unrelated diagnoses. Inasmuch as the Rules are clinical tools, they are applied throughout this monograph to diverse pathologic conditions typical in contemporary practice.

  4. Disorders of Acid-Base Balance: New Perspectives.

    Science.gov (United States)

    Seifter, Julian L; Chang, Hsin-Yun

    2017-01-01

    Disorders of acid-base involve the complex interplay of many organ systems including brain, lungs, kidney, and liver. Compensations for acid-base disturbances within the brain are more complete, while limitations of compensations are more apparent for most systemic disorders. However, some of the limitations on compensations are necessary to survival, in that preservation of oxygenation, energy balance, cognition, electrolyte, and fluid balance are connected mechanistically. This review aims to give new and comprehensive perspective on understanding acid-base balance and identifying associated disorders. All metabolic acid-base disorders can be approached in the context of the relative losses or gains of electrolytes or a change in the anion gap in body fluids. Acid-base and electrolyte balance are connected not only at the cellular level but also in daily clinical practice. Urine chemistry is essential to understanding electrolyte excretion and renal compensations. Many constructs are helpful to understand acid-base, but these models are not mutually exclusive. Electroneutrality and the close interconnection between electrolyte and acid-base balance are important concepts to apply in acid-base diagnoses. All models have complexity and shortcuts that can help in practice. There is no reason to dismiss any of the present constructs, and there is benefit in a combined approach.

  5. A new representation of acid-base disturbances

    NARCIS (Netherlands)

    M. Hekking (Marcel); E.S. Gelsema; J. Lindemans (Jan)

    1994-01-01

    textabstractThe acid-base status of intensive care patients is monitored on the basis of three quantities. The graphical representation which may be of help for the monitoring task is therefore cumbersome. The classical Siggaard-Andersen acid-base chart is such a representation, but it is only

  6. Metabolic acid-base disorders in the critical care unit.

    Science.gov (United States)

    de Morais, Helio Autran; Bach, Jonathan F; DiBartola, Stephen P

    2008-05-01

    The recognition and management of acid-base disorders is a commonplace activity in the critical care unit, and the role of weak and strong acids in the genesis of metabolic acid-base disorders is reviewed. The clinical approach to patients with metabolic alkalosis and metabolic acidosis is discussed in this article.

  7. Operating a redox flow battery with a negative electrolyte imbalance

    Energy Technology Data Exchange (ETDEWEB)

    Pham, Quoc; Chang, On; Durairaj, Sumitha

    2015-03-31

    Loss of flow battery electrode catalyst layers during self-discharge or charge reversal may be prevented by establishing and maintaining a negative electrolyte imbalance during at least parts of a flow battery's operation. Negative imbalance may be established and/or maintained actively, passively or both. Actively establishing a negative imbalance may involve detecting an imbalance that is less negative than a desired threshold, and processing one or both electrolytes until the imbalance reaches a desired negative level. Negative imbalance may be effectively established and maintained passively within a cell by constructing a cell with a negative electrode chamber that is larger than the cell's positive electrode chamber, thereby providing a larger quantity of negative electrolyte for reaction with positive electrolyte.

  8. [Cardiac arrhythmias caused by electrolyte imbalance].

    Science.gov (United States)

    Nishimura, M; Nakayama, K; Ishikawa, Y

    1996-08-01

    Cardiac arrhythmias are known to be caused by many factors. Among them, electrolyte imbalance is the most important because of electrical activity of the heart is composed of transmembrane fluxes of Na+, Ca2+ and K+. In this review article, we describe the effects of high or low concentrations of these electrolytes on the active and passive electrical properties of the membrane in the cardiac tissues, and the mechanisms by which these electrolytes cause abnormal impulse formation and conduction in the heart. Antagonism and synergism of electrolytes and pathological conditions such as digitalis intoxication and ischemia are discussed with respect to not only cardiac electrophysiology but also cellular metabolism. A pathophysiological role of Mg2+ to maintain normal excitation and conduction of the heart is also pointed out.

  9. Respiratory Acid-Base Disorders in the Critical Care Unit.

    Science.gov (United States)

    Hopper, Kate

    2017-03-01

    The incidence of respiratory acid-base abnormalities in the critical care unit (CCU) is unknown, although respiratory alkalosis is suspected to be common in this population. Abnormal carbon dioxide tension can have many physiologic effects, and changes in Pco 2 may have a significant impact on outcome. Monitoring Pco 2 in CCU patients is an important aspect of critical patient assessment, and identification of respiratory acid-base abnormalities can be valuable as a diagnostic tool. Treatment of respiratory acid-base disorders is largely focused on resolution of the primary disease, although mechanical ventilation may be indicated in cases with severe respiratory acidosis. Published by Elsevier Inc.

  10. Effort reward imbalance, and salivary cortisol in the morning

    DEFF Research Database (Denmark)

    Eller, Nanna Hurwitz; Nielsen, Søren Feodor; Blønd, Morten

    2012-01-01

    Effort reward imbalance (ERI) is suggested to increase risk for stress and is hypothesized to increase cortisol levels, especially the awakening cortisol response, ACR.......Effort reward imbalance (ERI) is suggested to increase risk for stress and is hypothesized to increase cortisol levels, especially the awakening cortisol response, ACR....

  11. Genomic imbalances in pediatric patients with chronic kidney disease

    OpenAIRE

    Verbitsky, Miguel; Sanna-Cherchi, Simone; Fasel, David A.; Levy, Brynn; Kiryluk, Krzysztof; Wuttke, Matthias; Abraham, Alison G.; Kaskel, Frederick; Köttgen, Anna; Warady, Bradley A.; Furth, Susan L; Wong, Craig S.; Gharavi, Ali G.

    2015-01-01

    BACKGROUND. There is frequent uncertainty in the identification of specific etiologies of chronic kidney disease (CKD) in children. Recent studies indicate that chromosomal microarrays can identify rare genomic imbalances that can clarify the etiology of neurodevelopmental and cardiac disorders in children; however, the contribution of unsuspected genomic imbalance to the incidence of pediatric CKD is unknown.

  12. Teaching acid/base physiology in the laboratory

    DEFF Research Database (Denmark)

    Friis, Ulla G; Plovsing, Ronni; Hansen, Klaus

    2010-01-01

    Acid/base homeostasis is one of the most difficult subdisciplines of physiology for medical students to master. A different approach, where theory and practice are linked, might help students develop a deeper understanding of acid/base homeostasis. We therefore set out to develop a laboratory...... exercise in acid/base physiology that would provide students with unambiguous and reproducible data that clearly would illustrate the theory in practice. The laboratory exercise was developed to include both metabolic acidosis and respiratory alkalosis. Data were collected from 56 groups of medical...... students that had participated in this laboratory exercise. The acquired data showed very consistent and solid findings after the development of both metabolic acidosis and respiratory alkalosis. All results were consistent with the appropriate diagnosis of the acid/base disorder. Not one single group...

  13. Biologist's Toolbox. Acid-base Balance: An Educational Computer Game.

    Science.gov (United States)

    Boyle, Joseph, III; Robinson, Gloria

    1987-01-01

    Describes a microcomputer program that can be used in teaching the basic physiological aspects of acid-base (AB) balance. Explains how its game format and graphic approach can be applied in diagnostic and therapeutic exercises. (ML)

  14. Acid-base homeostasis in the human system

    Science.gov (United States)

    White, R. J.

    1974-01-01

    Acid-base regulation is a cooperative phenomena in vivo with body fluids, extracellular and intracellular buffers, lungs, and kidneys all playing important roles. The present account is much too brief to be considered a review of present knowledge of these regulatory systems, and should be viewed, instead, as a guide to the elements necessary to construct a simple model of the mutual interactions of the acid-base regulatory systems of the body.

  15. Golden Jubilee Photos: A Universal Imbalance

    CERN Multimedia

    2004-01-01

    http://www.cern.ch/cern50/ View along the NA48 beamline with the detector in the distance. No one is sure why the Universe wound up the way it has: all matter and no antimatter. According to prevailing theories, the early universe had equal amounts of matter and antimatter. However, whenever such opposites meet, they annihilate and become a burst of energy. This would seem to leave the Universe with neither matter nor antimatter - and thus no stars, planets, or physicists. If nature shows a bias for matter over antimatter, this could explain why the Universe is all matter. To see what might be missing from the theories, physicists search for the rare cases in which matter and antimatter behave differently. One such imbalance, called direct CP violation, showed up in the NA 31 experiment at CERN. The results from this experiment, first presented in 1993, showed that when K mesons and their antimatter cousins decay, they show a slight preference for matter over antimatter. Later experiments with neutral K mes...

  16. Large Genomic Imbalances in Brugada Syndrome.

    Directory of Open Access Journals (Sweden)

    Irene Mademont-Soler

    Full Text Available Brugada syndrome (BrS is a form of cardiac arrhythmia which may lead to sudden cardiac death. The recommended genetic testing (direct sequencing of SCN5A uncovers disease-causing SNVs and/or indels in ~20% of cases. Limited information exists about the frequency of copy number variants (CNVs in SCN5A in BrS patients, and the role of CNVs in BrS-minor genes is a completely unexplored field.220 BrS patients with negative genetic results were studied to detect CNVs in SCN5A. 63 cases were also screened for CNVs in BrS-minor genes. Studies were performed by Multiplex ligation-dependent probe amplification or Next-Generation Sequencing (NGS.The detection rate for CNVs in SCN5A was 0.45% (1/220. The detected imbalance consisted of a duplication from exon 15 to exon 28, and could potentially explain the BrS phenotype. No CNVs were found in BrS-minor genes.CNVs in current BrS-related genes are uncommon among BrS patients. However, as these rearrangements may underlie a portion of cases and they undergo unnoticed by traditional sequencing, an appealing alternative to conventional studies in these patients could be targeted NGS, including in a single experiment the study of SNVs, indels and CNVs in all the known BrS-related genes.

  17. Genomic imbalances in syndromic congenital heart disease.

    Science.gov (United States)

    Molck, Miriam Coelho; Simioni, Milena; Paiva Vieira, Társis; Sgardioli, Ilária Cristina; Paoli Monteiro, Fabíola; Souza, Josiane; Fett-Conte, Agnes Cristina; Félix, Têmis Maria; Lopes Monlléo, Isabella; Gil-da-Silva-Lopes, Vera Lúcia

    To identify pathogenic genomic imbalances in patients presenting congenital heart disease (CHD) with extra cardiac anomalies and exclusion of 22q11.2 deletion syndrome (22q11.2 DS). 78 patients negative for the 22q11.2 deletion, previously screened by fluorescence in situ hybridization (FISH) and/or multiplex ligation probe amplification (MLPA) were tested by chromosomal microarray analysis (CMA). Clinically significant copy number variations (CNVs ≥300kb) were identified in 10% (8/78) of cases. In addition, potentially relevant CNVs were detected in two cases (993kb duplication in 15q21.1 and 706kb duplication in 2p22.3). Genes inside the CNV regions found in this study, such as IRX4, BMPR1A, SORBS2, ID2, ROCK2, E2F6, GATA4, SOX7, SEMAD6D, FBN1, and LTPB1 are known to participate in cardiac development and could be candidate genes for CHD. These data showed that patients presenting CHD with extra cardiac anomalies and exclusion of 22q11.2 DS should be investigated by CMA. The present study emphasizes the possible role of CNVs in CHD. Copyright © 2017 Sociedade Brasileira de Pediatria. Published by Elsevier Editora Ltda. All rights reserved.

  18. Disturbed acid-base transport: an emerging cause of hypertension

    Directory of Open Access Journals (Sweden)

    Ebbe eBoedtkjer

    2013-12-01

    Full Text Available Genome-wide association studies and physiological investigations have linked alterations in acid-base transporters to hypertension. Accordingly, Na+-coupled HCO3--transporters, Na+/H+-exchangers, and anion-exchangers have emerged as putative mechanistic components in blood pressure disturbances. Even though hypertension has been studied extensively over the last several decades, the cause of the high blood pressure has in most cases not been identified. Renal, cardiovascular, and neuronal dysfunctions all seem to play a role in hypertension development but their relative importance and mutual interdependency are still being debated. Multiple functional and structural alterations have been described in patients and animals with hypertension but it is typically unclear whether they are causes or consequences of hypertension or represent mechanistically unrelated associations. Perturbed blood pressure regulation has been demonstrated in several animal models with disrupted expression of acid-base transporters; and reciprocally, disturbed acid-base transport function has been described in hypertensive individuals. In addition to regulating intracellular and extracellular pH, Na+-coupled HCO3--transport, Na+/H+-exchange, and anion-exchange also contribute to water and electrolyte balance in cells and systemically. Since acid-base transporters are widely expressed, alterations in transport activities likely affect multiple cell and organ functions, and it is a significant challenge to determine the mechanisms linking perturbed acid-base transport function to hypertension. It is the purpose of this review to evaluate the current evidence for involvement of acid-base transporters in hypertension development and discuss the cellular and integrative mechanisms, which may link changes in acid-base transport to blood pressure disturbances.

  19. Spatial-frequency dependent binocular imbalance in amblyopia

    Science.gov (United States)

    Kwon, MiYoung; Wiecek, Emily; Dakin, Steven C.; Bex, Peter J.

    2015-01-01

    While amblyopia involves both binocular imbalance and deficits in processing high spatial frequency information, little is known about the spatial-frequency dependence of binocular imbalance. Here we examined binocular imbalance as a function of spatial frequency in amblyopia using a novel computer-based method. Binocular imbalance at four spatial frequencies was measured with a novel dichoptic letter chart in individuals with amblyopia, or normal vision. Our dichoptic letter chart was composed of band-pass filtered letters arranged in a layout similar to the ETDRS acuity chart. A different chart was presented to each eye of the observer via stereo-shutter glasses. The relative contrast of the corresponding letter in each eye was adjusted by a computer staircase to determine a binocular Balance Point at which the observer reports the letter presented to either eye with equal probability. Amblyopes showed pronounced binocular imbalance across all spatial frequencies, with greater imbalance at high compared to low spatial frequencies (an average increase of 19%, p binocular imbalance may be useful for diagnosing amblyopia and as an outcome measure for recovery of binocular vision following therapy. PMID:26603125

  20. Chromosomal imbalances are uncommon in chagasic megaesophagus

    Directory of Open Access Journals (Sweden)

    Silva Ana E

    2010-02-01

    Full Text Available Abstract Background Chagas' disease is a human tropical parasitic illness and a subset of the chronic patients develop megaesophagus or megacolon. The esophagus dilation is known as chagasic megaesophagus (CM and one of the severe late consequences of CM is the increased risk for esophageal carcinoma (ESCC. Based on the association between CM and ESCC, we investigated whether genes frequently showing unbalanced copy numbers in ESCC were altered in CM by fluorescence in situ (FISH technology. Methods A total of 50 formalin-fixed, paraffin-embedded esophageal mucosa specimens (40 from Chagas megaesophagus-CM, and 10 normal esophageal mucosa-NM were analyzed. DNA FISH probes were tested for FHIT, TP63, PIK3CA, EGFR, FGFR1, MYC, CDKN2A, YES1 and NCOA3 genes, and centromeric sequences from chromosomes 3, 7 and 9. Results No differences between superficial and basal layers of the epithelial mucosa were found, except for loss of copy number of EGFR in the esophageal basal layer of CM group. Mean copy number of CDKN2A and CEP9 and frequency of nuclei with loss of PIK3CA were significantly different in the CM group compared with normal mucosa and marginal levels of deletions in TP63, FHIT, PIK3CA, EGFR, CDKN2A, YES and gains at PIK3CA, TP63, FGFR1, MYC, CDNK2A and NCOA3 were detected in few CM cases, mainly with dilation grades III and IV. All changes occurred at very low levels. Conclusions Genomic imbalances common in esophageal carcinomas are not present in chagasic megaesophagus suggesting that these features will not be effective markers for risk assessment of ESCC in patients with chagasic megaesophagus.

  1. Measuring Earth's Radiation Imbalance using Cubesat Constellations

    Science.gov (United States)

    Collins, W. D.; Courtade, S.; Immel, T. J.; Feldman, D.; Lorentz, S. R.; Dyrud, L. P.

    2016-12-01

    At present, the global annual-mean Earth Radiation Imbalance (ERI) is estimated to be of order 1 W/m2, although the uncertainty in ERI is much larger than this estimate. The best current satellite-only observational determinations of ERI range from -2 to +7 W/m2 unless major adjustments are made using ocean observations. Since measurements of ERI accurate to better than 0.5 W/m2 are essential for understanding and predicting changes in our climate, new missions to determine ERI in conjunction with ongoing ocean observations are urgently needed. These missions should reliably determine Earth's radiation balance at the temporal and spatial scales sufficient for relating ERI to the physical processes responsible for variability. The compelling objective of measuring ERI can be met using a constellation of satellites making global, high-frequency radiation measurements of the solar energy reflected and infrared energy radiated back to space with sufficient accuracy to determine the ERI to within 0.5 W/m2. In this presentation, we discuss the reasons and prospects for deploying a Cubesat constellation to realize this objective, simulations of the data that could be produced by this constellation, and the advantages of the spatial coverage and high temporal frequency afforded by the constellation. These advantages apply both to estimating long-term ERI and to quantifying the radiation budgets of individual synoptic-scale weather systems. The innovations in this system involve both the use of Cubesats and of compact, continuously calibrated wide-field-of-view radiometers. We demonstrate the feasibility of such a constellation using the ongoing proof-of-concept deployment of the target radiometers onboard the upcoming NASA RAVAN (Radiometer Assessment using Vertically Aligned Nanotubes) mission.

  2. Ammonia Transporters and Their Role in Acid-Base Balance.

    Science.gov (United States)

    Weiner, I David; Verlander, Jill W

    2017-04-01

    Acid-base homeostasis is critical to maintenance of normal health. Renal ammonia excretion is the quantitatively predominant component of renal net acid excretion, both under basal conditions and in response to acid-base disturbances. Although titratable acid excretion also contributes to renal net acid excretion, the quantitative contribution of titratable acid excretion is less than that of ammonia under basal conditions and is only a minor component of the adaptive response to acid-base disturbances. In contrast to other urinary solutes, ammonia is produced in the kidney and then is selectively transported either into the urine or the renal vein. The proportion of ammonia that the kidney produces that is excreted in the urine varies dramatically in response to physiological stimuli, and only urinary ammonia excretion contributes to acid-base homeostasis. As a result, selective and regulated renal ammonia transport by renal epithelial cells is central to acid-base homeostasis. Both molecular forms of ammonia, NH3 and NH4(+), are transported by specific proteins, and regulation of these transport processes determines the eventual fate of the ammonia produced. In this review, we discuss these issues, and then discuss in detail the specific proteins involved in renal epithelial cell ammonia transport. Copyright © 2017 the American Physiological Society.

  3. Assessment of acid-base balance. Stewart's approach.

    Science.gov (United States)

    Fores-Novales, B; Diez-Fores, P; Aguilera-Celorrio, L J

    2016-04-01

    The study of acid-base equilibrium, its regulation and its interpretation have been a source of debate since the beginning of 20th century. Most accepted and commonly used analyses are based on pH, a notion first introduced by Sorensen in 1909, and on the Henderson-Hasselbalch equation (1916). Since then new concepts have been development in order to complete and make easier the understanding of acid-base disorders. In the early 1980's Peter Stewart brought the traditional interpretation of acid-base disturbances into question and proposed a new method. This innovative approach seems more suitable for studying acid-base abnormalities in critically ill patients. The aim of this paper is to update acid-base concepts, methods, limitations and applications. Copyright © 2015 Sociedad Española de Anestesiología, Reanimación y Terapéutica del Dolor. Publicado por Elsevier España, S.L.U. All rights reserved.

  4. Abnormalities of acid-base balance and predisposition to metabolic acidosis in Metachromatic Leukodystrophy patients.

    Science.gov (United States)

    Lorioli, L; Cicalese, M P; Silvani, P; Assanelli, A; Salvo, I; Mandelli, A; Fumagalli, F; Fiori, R; Ciceri, F; Aiuti, A; Sessa, M; Roncarolo, M G; Lanzani, C; Biffi, A

    2015-05-01

    Metachromatic Leukodystrophy (MLD; MIM# 250100) is a rare inherited lysosomal storage disorder caused by the deficiency of Arylsulfatase A (ARSA). The enzymatic defect results in the accumulation of the ARSA substrate that is particularly relevant in myelin forming cells and leads to progressive dysmyelination and dysfunction of the central and peripheral nervous system. Sulfatide accumulation has also been reported in various visceral organs, although little is known about the potential clinical consequences of such accumulation. Different forms of MLD-associated gallbladder disease have been described, and there is one reported case of an MLD patient presenting with functional consequences of sulfatide accumulation in the kidney. Here we describe a wide cohort of MLD patients in whom a tendency to sub-clinical metabolic acidosis was observed. Furthermore in some of them we report episodes of metabolic acidosis of different grades of severity developed in acute clinical conditions of various origin. Importantly, we finally show how a careful acid-base balance monitoring and prompt correction of imbalances might prevent severe consequences of acidosis. Copyright © 2015 Elsevier Inc. All rights reserved.

  5. Assessing Acid-Base Status: Physiologic Versus Physicochemical Approach.

    Science.gov (United States)

    Adrogué, Horacio J; Madias, Nicolaos E

    2016-11-01

    The physiologic approach has long been used in assessing acid-base status. This approach considers acids as hydrogen ion donors and bases as hydrogen ion acceptors and the acid-base status of the organism as reflecting the interaction of net hydrogen ion balance with body buffers. In the physiologic approach, the carbonic acid/bicarbonate buffer pair is used for assessing acid-base status and blood pH is determined by carbonic acid (ie, Paco2) and serum bicarbonate levels. More recently, the physicochemical approach was introduced, which has gained popularity, particularly among intensivists and anesthesiologists. This approach posits that the acid-base status of body fluids is determined by changes in the dissociation of water that are driven by the interplay of 3 independent variables: the sum of strong (fully dissociated) cation concentrations minus the sum of strong anion concentrations (strong ion difference); the total concentration of weak acids; and Paco2. These 3 independent variables mechanistically determine both hydrogen ion concentration and bicarbonate concentration of body fluids, which are considered as dependent variables. Our experience indicates that the average practitioner is familiar with only one of these approaches and knows very little, if any, about the other approach. In the present Acid-Base and Electrolyte Teaching Case, we attempt to bridge this knowledge gap by contrasting the physiologic and physicochemical approaches to assessing acid-base status. We first outline the essential features, advantages, and limitations of each of the 2 approaches and then apply each approach to the same patient presentation. We conclude with our view about the optimal approach. Copyright © 2016 National Kidney Foundation, Inc. All rights reserved.

  6. History of nutrition and acid-base physiology.

    Science.gov (United States)

    Manz, F

    2001-10-01

    In the 17th century the notion of nutrition and diet changed in northern European countries. First chemical experiments fostered the idea that salts resulted from a union of acids and bases. Digestion was no more regarded as a process of cooking but a succession of fermentations controlled by a balanced production of acids and alkali. Life seemed to depend on the equilibrium of acids and alkalis. In the 19th century food was systematically analysed for the content of energy and macronutrients and first scientifically based nutritional standards were formulated. The preferred use of processed food from the new food industry resulted in epidemics of nutritional disorders. Acidosis seemed to be a plausible pathogenic factor. Practitioners (S Ishizuka, H Hay, FX Mayr) formulated holistic doctrines integrating the concept of balance of acids and bases and recommending food with an excess of alkali. New micromethods to determine the concentration of electrolytes and blood acid-base status promoted physiological and clinical research into acid-base metabolism in the 1960s. In the new physiologically based terminology of systemic acid-base status, the relationship between blood acid-base status and net acid intake or excretion was, however, incorrectly simplified. In the 1970s metabolic acidosis was observed in patients on chemically defined diets and parenteral nutrition. Based on the data of comprehensive acid-base balance studies, calculation models were used to estimate renal net acid excretion from nutrient intake and to predict the potential renal acid load of single foods. Extrapolating current trends to the future, one can say that acid-base physiology will probably remain a challenge in nutrition and functional medicine over the next few years. The challenge will include new concepts for the manipulation of nutritional acid load in sports, dietetics and preventive medicine as well as new definitions of the upper intake level of potential renal acid load in

  7. Genomic imbalance in subjects with idiopathic intellectual disability ...

    Indian Academy of Sciences (India)

    Genomic imbalance in subjects with idiopathic intellectual disability detected by multiplex ligation-dependent probe amplification. SHRUTHI MOHAN VETTRISELVI VENKATESAN SOLOMON FD PAUL TEEENA KOSHY VENKATACHALAM PERUMAL. RESEARCH NOTE Volume 95 Issue 2 June 2016 pp 469-474 ...

  8. East-West News Flow "Imbalance": Qualifying the Quantifications.

    Science.gov (United States)

    Le Duc, Don R.

    1981-01-01

    A study of Eurovision-Intervision news exchange patterns suggests that any global explanation for imbalance will be premature until the news item values in each exchange are understood as clearly as its news item volume. (PD)

  9. Chiral Imbalance in QCD and its consequences

    Directory of Open Access Journals (Sweden)

    Andrianov Alexander

    2016-01-01

    Full Text Available Under extreme conditions of high temperature and/or large quark (baryon density, the vacuum of QCD changes its properties, and deconfinement, chiral symmetry restoration as well as chiral symmetry breaking take place. These transitions (phases are accompanied by the rapid change in the rate and nature of topological transitions connecting different topological sectors. The heavy ion collisions (HIC program opens a possibility to study these phenomena in so-called non-Abelian Quark-gluon plasma (QGP. In these phases the currents of light quarks (vector and axial-vector can be independently examined for right-handed (RH and left-handed (LH quarks. To describe such a quark matter chiral chemical potential can be introduced to quantify the presence of chirality imbalance (ChI i.e. the difference between the average numbers of RH and LH quarks in the fireball after HIC. In this review talk we will focus our attention on the discussion of the ChI related developments in heavy ion physics at central collisions and the plans for the future experiments aimed at establishing (or falsifying the presence of Local spacial Parity Breaking (LPB in heavy ion data. We describe some of experimental observables in detecting the signal of LPB. A number of measurements is proposed that allow to reach a definite conclusion on the occurrence of LPB effects in non-Abelian QGP produced in central heavy ion collisions and its simulation within a number of QCD-inspired models is outlined. Based on the effective meson theory in the presence of Chern-Simons interaction it is found that the spectrum of massive vector mesons splits into three polarization components with different effective masses. Moreover a resonance broadening occurs that leads to an increase of spectral contribution to the dilepton production as compared to the vacuum state. The asymmetry in production of longitudinally and transversely polarized states of ρ and ω mesons for various values of the

  10. Acid-base disturbance in patients with cirrhosis

    DEFF Research Database (Denmark)

    Henriksen, Jens H; Bendtsen, Flemming; Møller, Søren

    2015-01-01

    PURPOSE: Acid-base disturbances were investigated in patients with cirrhosis in relation to hemodynamic derangement to analyze the hyperventilatory effects and the metabolic compensation. METHODS: A total of 66 patients with cirrhosis and 44 controls were investigated during a hemodynamic study......, and effects of unidentified ions (all Pacid-base disturbances could not be identified. CONCLUSION: Hypocapnic alkalosis is related to disease severity and hyperdynamic systemic circulation in patients with cirrhosis. The metabolic compensation includes...... alterations in serum albumin and water retention that may result in a delicate acid-base balance in these patients....

  11. Acids and bases solvent effects on acid-base strenght

    CERN Document Server

    Cox, Brian G

    2013-01-01

    Acids and bases are ubiquitous in chemistry. Our understanding of them, however, is dominated by their behaviour in water. Transfer to non-aqueous solvents leads to profound changes in acid-base strengths and to the rates and equilibria of many processes: for example, synthetic reactions involving acids, bases and nucleophiles; isolation of pharmaceutical actives through salt formation; formation of zwitter- ions in amino acids; and chromatographic separation of substrates. This book seeks to enhance our understanding of acids and bases by reviewing and analysing their behaviour in non-aqueous solvents. The behaviour is related where possible to that in water, but correlations and contrasts between solvents are also presented.

  12. Competitiveness and external imbalances within the euro area

    OpenAIRE

    2012-01-01

    The onset of the financial crisis in 2008 has highlighted the problems of diverging external imbalances within Economic and Monetary Union (EMU) and the role of persistent losses in competitiveness. This paper starts by investigating some of the competitiveness factors which contributed to external imbalances in euro area countries. The evidence suggests significant heterogeneity across countries in both price/cost and non-price competitiveness in the euro area and that there is no one factor...

  13. Soil Studies: Applying Acid-Base Chemistry to Environmental Analysis.

    Science.gov (United States)

    West, Donna M.; Sterling, Donna R.

    2001-01-01

    Laboratory activities for chemistry students focus attention on the use of acid-base chemistry to examine environmental conditions. After using standard laboratory procedures to analyze soil and rainwater samples, students use web-based resources to interpret their findings. Uses CBL probes and graphing calculators to gather and analyze data and…

  14. Students' Understanding of Acids/Bases in Organic Chemistry Contexts

    Science.gov (United States)

    Cartrette, David P.; Mayo, Provi M.

    2011-01-01

    Understanding key foundational principles is vital to learning chemistry across different contexts. One such foundational principle is the acid/base behavior of molecules. In the general chemistry sequence, the Bronsted-Lowry theory is stressed, because it lends itself well to studying equilibrium and kinetics. However, the Lewis theory of…

  15. Intravenous fluid administration and controversies in Acid-base.

    Science.gov (United States)

    Story, D A

    1999-06-01

    To present an overview of acidosis following intravenous fluid infusion and to highlight the current controversy in acid-base physiology. Articles and reviews from peer reviewed journals and books on acid-base physiology and post infusion acidosis. Infusion of intravenous fluids can produce an acidosis particularly in the setting of large volume infusion. The explanation of this phenomenon has centred around dilution of plasma bicarbonate. An alternative explanation can be found in the work of Peter Stewart, which highlights the use of strong ion difference in assessing metabolic acidosis. The Stewart approach differs from the traditional Henderson-Hasselbalch approach to acid-base. Further study is required to determine which approach is correct. Solutions containing base anions such as lactate may attenuate such an infusion acidosis. Animal and clinical studies using Hartmann's solution and Plasmalyte 148 support this idea. There is controversy regarding mechanisms in acid-base physiology. The clinical significance of post infusion acidosis is unclear, however use of Hartmann's solution may minimize the acidosis.

  16. A dipstick sensor for coulometric acid-base titrations

    NARCIS (Netherlands)

    Olthuis, Wouter; van der Schoot, B.H.; Chavez, F.; Bergveld, Piet

    1989-01-01

    By performing an acid-base titration by coulometric generation of OH− or H+ ions at an inert electrode in close proximity to the pH-sensitive gate of an ISFET, it is possible to determine the acid or base concentration of a solution using the ISFET as an indicator device for the equivalence point in

  17. Acid-base balance in peritoneal dialysis patients: a Stewart-Fencl analysis.

    Science.gov (United States)

    Klaboch, Jan; Opatrná, Sylvie; Matousovic, Karel; Sefrna, Frantisek; Havlín, Jan; Schück, Otto

    2009-01-01

    Evaluation of acid-base disorders using the Stewart-Fencl principle is based on assessment of independent factors: strong ion difference (SID) and the total concentration of non-volatile weak acids (Atot). This approach allows for a more detailed evaluation of the cause of acid-base imbalance than the conventional bicarbonate-centered approach based on the Henderson-Hasselbalch principle, which is a necessary yet insufficient condition to describe the state of the system. The aim of our study was to assess acid-base disorders in peritoneal dialysis (PD) patients using both of these principles. A total of 17 patients with chronic renal failure (10 men), aged 60.7 (22-84) years, treated by PD for 25.7 (1-147) months were examined. A control group included 17 healthy volunteers (HV) (8 males), with a mean age of 42.7 (22-77) years and normal renal function. Patients were treated with a solution containing bicarbonate (25 mmol/L) and lactate (15 mmol/L) as buffers; eleven of them used, during the nighttime dwell, a solution with icodextrin buffered by lactate at a concentration of 40 mmol/L. The following equations were employed for calculations of acid-base parameters according to the Stewart-Fencl principle. The first is SID = [Na+] + [K+] + 2[Ca(2+)] + 2[Mg(2+)] - [Cl-] - [UA-], where SID is the strong ion difference and [UA-] is the concentration of undetermined anions. For practical calculation of SID, the second equation, SID = [HCO3-] + [Alb-] + [Pi-], was used, where [Alb-] and [Pi-] are the charges carried by albumin and phosphates. The third is Atot, the total concentration of weak non-volatile acids, albumin [Alb] and phosphates [Pi]. The capillary blood pH in PD group was 7.41 (7.27-7.48), [HCO3-] levels 23.7 (17.6-29.5) mmol/L, SID 36.3 (29.5-41.3) mmol/L, sodium-chloride difference 39.0 (31.0-44.0) mmol/L, [Pi] 1.60 (0.83-2.54) mmol/L, and [Alb] 39.7 (28.8-43.4) g/L (median, min-max). Bicarbonate in blood correlated positively with SID (Rho = 0.823; p < 0

  18. Pathophysiology of acid base balance: the theory practice relationship.

    Science.gov (United States)

    Edwards, Sharon L

    2008-02-01

    There are many disorders/diseases that lead to changes in acid base balance. These conditions are not rare or uncommon in clinical practice, but everyday occurrences on the ward or in critical care. Conditions such as asthma, chronic obstructive pulmonary disease (bronchitis or emphasaemia), diabetic ketoacidosis, renal disease or failure, any type of shock (sepsis, anaphylaxis, neurogenic, cardiogenic, hypovolaemia), stress or anxiety which can lead to hyperventilation, and some drugs (sedatives, opioids) leading to reduced ventilation. In addition, some symptoms of disease can cause vomiting and diarrhoea, which effects acid base balance. It is imperative that critical care nurses are aware of changes that occur in relation to altered physiology, leading to an understanding of the changes in patients' condition that are observed, and why the administration of some immediate therapies such as oxygen is imperative.

  19. [Blood acid-base balance of sportsmen during physical activity].

    Science.gov (United States)

    Petrushova, O P; Mikulyak, N I

    2014-01-01

    The aim of this study was to investigate the acid-base balance parameters in blood of sportsmen by physical activity. Before exercise lactate concentration in blood was normal. Carbon dioxide pressure (рСО2), bicarbonate concentration (НСО3 -), base excess (BE), were increased immediately after physical activity lactate concentration increased, while pH, BE, НСО3 -, рСО2 decreased in capillary blood of sportsmen. These changes show the development of lactate-acidosis which is partly compensated with bicarbonate buffering system and respiratory alkalosis. During postexercise recovery lactate concentration decreased, while рСО2, НСО3 -, BE increased. The results of this study can be used for diagnostics of acid-base disorders and their medical treatment for preservation of sportsmen physical capacity.

  20. Exotic meson decays in the environment with chiral imbalance

    Science.gov (United States)

    Andrianov, A. A.; Andrianov, V. A.; Espriu, D.; Iakubovich, A. V.; Putilova, A. E.

    2017-10-01

    An emergence of Local Parity Breaking (LPB) in central heavy-ion collisions (HIC) at high energies is discussed. LPB in the fireball can be produced by a difference between the number densities of right- and left-handed chiral fermions (Chiral Imbalance) which is implemented by a chiral (axial) chemical potential. The effective meson lagrangian induced by QCD is extended to the medium with Chiral Imbalance and the properties of light scalar and pseudoscalar mesons (π, α0) are analyzed. It is shown that exotic decays of scalar mesons arise as a result of mixing of π and α0 vacuum states in the presence of chiral imbalance. The pion electromagnetic formfactor obtains an unusual parity-odd supplement which generates a photon polarization asymmetry in pion polarizability. We hope that the above pointed indications of LPB can be identified in experiments on LHC, RHIC, CBM FAIR and NICA accelerators.

  1. How gender disparities drive imbalances in health care leadership

    Directory of Open Access Journals (Sweden)

    Hoss MAK

    2011-11-01

    Full Text Available Mary Ann Keogh Hoss1, Paula Bobrowski2, Kathryn J McDonagh3, Nancy M Paris41Health Services Administration, Eastern Washington University, College of Business and Public Administration, Spokane, WA, USA; 2College of Liberal Arts, Auburn University, Auburn, AL, USA; 3Executive Relations, Hospira Inc, Lake Forest, IL, USA; 4Georgia Center for Oncology Research and Education, Atlanta, GA, USAAbstract: Low female representation in US hospital chief executive officer positions has persisted for decades. This article addresses gender disparity in professional development, the rationale for gender differences, and practical strategies to address this imbalance. The health care workforce consists of 75% women, but according to two recent surveys, ie, a state survey and a survey of the top 100 US hospitals, women hold only about 12% of chief executive officer positions in US hospitals. Significant and dedicated efforts by both individuals and organizations are necessary to rectify this imbalance.Keywords: gender, imbalance, leadership, United States, hospitals

  2. Neoliberalism, trade imbalances, and economic policy in the Eurozone crisis

    Directory of Open Access Journals (Sweden)

    Engelbert Stockhammer

    2016-12-01

    Full Text Available This paper analyzes the causes of the Eurozone crisis. In doing so, it carefully surveys authors from different economic schools of thought. The paper discusses competing explanations for European current account imbalances. Remarkably, opposing views on the relative importance of cost developments and demand developments in explaining current account imbalances can be found in both heterodox and orthodox economics. Regarding the assessment of fiscal and monetary policy there is a clearer polarisation, with heterodox analysis regarding austerity as unhelpful and most of orthodox economics endorsing it. We advocate a post-Keynesian view, which holds that current account imbalances are not a fundamental cause of the sovereign debt crisis. Rather, the economic policy architecture of the Eurozone, which aims at restricting the role of fiscal and monetary policy, is the key to understanding the crisis in Europe.

  3. Exotic meson decays in the environment with chiral imbalance

    Directory of Open Access Journals (Sweden)

    Andrianov A. A.

    2017-01-01

    Full Text Available An emergence of Local Parity Breaking (LPB in central heavy-ion collisions (HIC at high energies is discussed. LPB in the fireball can be produced by a difference between the number densities of right- and left-handed chiral fermions (Chiral Imbalance which is implemented by a chiral (axial chemical potential. The effective meson lagrangian induced by QCD is extended to the medium with Chiral Imbalance and the properties of light scalar and pseudoscalar mesons (π, α0 are analyzed. It is shown that exotic decays of scalar mesons arise as a result of mixing of π and α0 vacuum states in the presence of chiral imbalance. The pion electromagnetic formfactor obtains an unusual parity-odd supplement which generates a photon polarization asymmetry in pion polarizability. We hope that the above pointed indications of LPB can be identified in experiments on LHC, RHIC, CBM FAIR and NICA accelerators.

  4. Pulmonary gas exchange and acid-base balance during exercise.

    Science.gov (United States)

    Stickland, Michael K; Lindinger, Michael I; Olfert, I Mark; Heigenhauser, George J F; Hopkins, Susan R

    2013-04-01

    As the first step in the oxygen-transport chain, the lung has a critical task: optimizing the exchange of respiratory gases to maintain delivery of oxygen and the elimination of carbon dioxide. In healthy subjects, gas exchange, as evaluated by the alveolar-to-arterial PO2 difference (A-aDO2), worsens with incremental exercise, and typically reaches an A-aDO2 of approximately 25 mmHg at peak exercise. While there is great individual variability, A-aDO2 is generally largest at peak exercise in subjects with the highest peak oxygen consumption. Inert gas data has shown that the increase in A-aDO2 is explained by decreased ventilation-perfusion matching, and the development of a diffusion limitation for oxygen. Gas exchange data does not indicate the presence of right-to-left intrapulmonary shunt developing with exercise, despite recent data suggesting that large-diameter arteriovenous shunt vessels may be recruited with exercise. At the same time, multisystem mechanisms regulate systemic acid-base balance in integrative processes that involve gas exchange between tissues and the environment and simultaneous net changes in the concentrations of strong and weak ions within, and transfer between, extracellular and intracellular fluids. The physicochemical approach to acid-base balance is used to understand the contributions from independent acid-base variables to measured acid-base disturbances within contracting skeletal muscle, erythrocytes and noncontracting tissues. In muscle, the magnitude of the disturbance is proportional to the concentrations of dissociated weak acids, the rate at which acid equivalents (strong acid) accumulate and the rate at which strong base cations are added to or removed from muscle.

  5. Antimicrobial-induced Electrolyte and Acid-Base Disturbances

    OpenAIRE

    Kim, Yang Wook

    2007-01-01

    Antimicrobials are one of the most widely prescribed classes of therapeutic agents. Although adverse effects of antimicrobials are generally minimal and reversible, serious sequelae can sometimes remain, such as unusual forms of renal failure, acid base disturbance and electrolyte abnormalities. Many antimicrobials, especially vancomycin or aminoglycosides, are associated with development of acute renal failure caused by acute tubular necrosis, allergic acute interstitial nephritis, or vascul...

  6. Parental genome dosage imbalance deregulates imprinting in Arabidopsis.

    Directory of Open Access Journals (Sweden)

    Pauline E Jullien

    2010-03-01

    Full Text Available In mammals and in plants, parental genome dosage imbalance deregulates embryo growth and might be involved in reproductive isolation between emerging new species. Increased dosage of maternal genomes represses growth while an increased dosage of paternal genomes has the opposite effect. These observations led to the discovery of imprinted genes, which are expressed by a single parental allele. It was further proposed in the frame of the parental conflict theory that parental genome imbalances are directly mirrored by antagonistic regulations of imprinted genes encoding maternal growth inhibitors and paternal growth enhancers. However these hypotheses were never tested directly. Here, we investigated the effect of parental genome imbalance on the expression of Arabidopsis imprinted genes FERTILIZATION INDEPENDENT SEED2 (FIS2 and FLOWERING WAGENINGEN (FWA controlled by DNA methylation, and MEDEA (MEA and PHERES1 (PHE1 controlled by histone methylation. Genome dosage imbalance deregulated the expression of FIS2 and PHE1 in an antagonistic manner. In addition increased dosage of inactive alleles caused a loss of imprinting of FIS2 and MEA. Although FIS2 controls histone methylation, which represses MEA and PHE1 expression, the changes of PHE1 and MEA expression could not be fully accounted for by the corresponding fluctuations of FIS2 expression. Our results show that parental genome dosage imbalance deregulates imprinting using mechanisms, which are independent from known regulators of imprinting. The complexity of the network of regulations between expressed and silenced alleles of imprinted genes activated in response to parental dosage imbalance does not support simple models derived from the parental conflict hypothesis.

  7. Parental genome dosage imbalance deregulates imprinting in Arabidopsis.

    Science.gov (United States)

    Jullien, Pauline E; Berger, Frédéric

    2010-03-19

    In mammals and in plants, parental genome dosage imbalance deregulates embryo growth and might be involved in reproductive isolation between emerging new species. Increased dosage of maternal genomes represses growth while an increased dosage of paternal genomes has the opposite effect. These observations led to the discovery of imprinted genes, which are expressed by a single parental allele. It was further proposed in the frame of the parental conflict theory that parental genome imbalances are directly mirrored by antagonistic regulations of imprinted genes encoding maternal growth inhibitors and paternal growth enhancers. However these hypotheses were never tested directly. Here, we investigated the effect of parental genome imbalance on the expression of Arabidopsis imprinted genes FERTILIZATION INDEPENDENT SEED2 (FIS2) and FLOWERING WAGENINGEN (FWA) controlled by DNA methylation, and MEDEA (MEA) and PHERES1 (PHE1) controlled by histone methylation. Genome dosage imbalance deregulated the expression of FIS2 and PHE1 in an antagonistic manner. In addition increased dosage of inactive alleles caused a loss of imprinting of FIS2 and MEA. Although FIS2 controls histone methylation, which represses MEA and PHE1 expression, the changes of PHE1 and MEA expression could not be fully accounted for by the corresponding fluctuations of FIS2 expression. Our results show that parental genome dosage imbalance deregulates imprinting using mechanisms, which are independent from known regulators of imprinting. The complexity of the network of regulations between expressed and silenced alleles of imprinted genes activated in response to parental dosage imbalance does not support simple models derived from the parental conflict hypothesis.

  8. Carbonic anhydrase 5 regulates acid-base homeostasis in zebrafish.

    Directory of Open Access Journals (Sweden)

    Ruben Postel

    Full Text Available The regulation of the acid-base balance in cells is essential for proper cellular homeostasis. Disturbed acid-base balance directly affects cellular physiology, which often results in various pathological conditions. In every living organism, the protein family of carbonic anhydrases regulate a broad variety of homeostatic processes. Here we describe the identification, mapping and cloning of a zebrafish carbonic anhydrase 5 (ca5 mutation, collapse of fins (cof, which causes initially a collapse of the medial fins followed by necrosis and rapid degeneration of the embryo. These phenotypical characteristics can be mimicked in wild-type embryos by acetazolamide treatment, suggesting that CA5 activity in zebrafish is essential for a proper development. In addition we show that CA5 regulates acid-base balance during embryonic development, since lowering the pH can compensate for the loss of CA5 activity. Identification of selective modulators of CA5 activity could have a major impact on the development of new therapeutics involved in the treatment of a variety of disorders.

  9. Electrolyte and acid-base abnormalities associated with purging behaviors.

    Science.gov (United States)

    Mehler, Philip S; Walsh, Kristine

    2016-03-01

    Eating disorders that are associated with purging behaviors are complicated by frequent blood electrolyte and acid-base abnormalities. Herein, we review the major electrolyte and acid-base abnormalities and their treatment methods. The body of rigorous, eating disorder-specific literature on this topical area is not robust enough to perform a systematic review as defined by PRISMA guidelines. Therefore, a qualitative review of mostly medical literature was conducted. Hypokalemia, hyponatremia, and sodium chloride-responsive metabolic alkalosis are the most common serum changes that occur as a result of purging behaviors. They vary depending on the mode and frequency of purging behaviors. They can all potentially cause dangerous medical complications and are in need of definitive medical treatment. Eating disorders that are associated with purging behaviors are associated with a number of electrolyte and acid-base changes which are complex in their origin, documented to be medically dangerous and this definitive treatment is necessary to help achieve a successful treatment outcome, and in need of definitive treatment as described herein. © 2016 Wiley Periodicals, Inc.

  10. Acid-base balance in uremic rats with vascular calcification.

    Science.gov (United States)

    Peralta-Ramírez, Alan; Raya, Ana Isabel; Pineda, Carmen; Rodríguez, Mariano; Aguilera-Tejero, Escolástico; López, Ignacio

    2014-01-01

    Vascular calcification (VC), a major complication in humans and animals with chronic kidney disease (CKD), is influenced by changes in acid-base balance. The purpose of this study was to describe the acid-base balance in uremic rats with VC and to correlate the parameters that define acid-base equilibrium with VC. Twenty-two rats with CKD induced by 5/6 nephrectomy (5/6 Nx) and 10 nonuremic control rats were studied. The 5/6 Nx rats showed extensive VC as evidenced by a high aortic calcium (9.2 ± 1.7 mg/g of tissue) and phosphorus (20.6 ± 4.9 mg/g of tissue) content. Uremic rats had an increased pH level (7.57 ± 0.03) as a consequence of both respiratory (PaCO2 = 28.4 ± 2.1 mm Hg) and, to a lesser degree, metabolic (base excess = 4.1 ± 1 mmol/l) derangements. A high positive correlation between both anion gap (AG) and strong ion difference (SID) with aortic calcium (AG: r = 0.604, p = 0.02; SID: r = 0.647, p = 0.01) and with aortic phosphorus (AG: r = 0.684, p = 0.007; SID: r = 0.785, p = 0.01) was detected. In an experimental model of uremic rats, VC showed high positive correlation with AG and SID.

  11. Neurologic complications of electrolyte disturbances and acid-base balance.

    Science.gov (United States)

    Espay, Alberto J

    2014-01-01

    Electrolyte and acid-base disturbances are common occurrences in daily clinical practice. Although these abnormalities can be readily ascertained from routine laboratory findings, only specific clinical correlates may attest as to their significance. Among a wide phenotypic spectrum, acute electrolyte and acid-base disturbances may affect the peripheral nervous system as arreflexic weakness (hypermagnesemia, hyperkalemia, and hypophosphatemia), the central nervous system as epileptic encephalopathies (hypomagnesemia, dysnatremias, and hypocalcemia), or both as a mixture of encephalopathy and weakness or paresthesias (hypocalcemia, alkalosis). Disabling complications may develop not only when these derangements are overlooked and left untreated (e.g., visual loss from intracranial hypertension in respiratory or metabolic acidosis; quadriplegia with respiratory insufficiency in hypermagnesemia) but also when they are inappropriately managed (e.g., central pontine myelinolisis when rapidly correcting hyponatremia; cardiac arrhythmias when aggressively correcting hypo- or hyperkalemia). Therefore prompt identification of the specific neurometabolic syndromes is critical to correct the causative electrolyte or acid-base disturbances and prevent permanent central or peripheral nervous system injury. This chapter reviews the pathophysiology, clinical investigations, clinical phenotypes, and current management strategies in disorders resulting from alterations in the plasma concentration of sodium, potassium, calcium, magnesium, and phosphorus as well as from acidemia and alkalemia. © 2014 Elsevier B.V. All rights reserved.

  12. SHOULDER MUSCLE IMBALANCE AND SUBACROMIAL IMPINGEMENT SYNDROME IN OVERHEAD ATHLETES

    Science.gov (United States)

    2011-01-01

    Subacromial impingement is a frequent and painful condition among athletes, particularly those involved in overhead sports such as baseball and swimming. There are generally two types of subacromial impingement: structural and functional. While structural impingement is caused by a physical loss of area in the subacromial space due to bony growth or inflammation, functional impingement is a relative loss of subacromial space secondary to altered scapulohumeral mechanics resulting from glenohumeral instability and muscle imbalance. The purpose of this review is to describe the role of muscle imbalance in subacromial impingement in order to guide sports physical therapy evaluation and interventions. PMID:21655457

  13. In-phase and quadrature imbalance modeling, estimation, and compensation

    CERN Document Server

    Li, Yabo

    2013-01-01

    This book provides a unified IQ imbalance model and systematically reviews the existing estimation and compensation schemes. It covers the different assumptions and approaches that lead to many models of IQ imbalance. In wireless communication systems, the In-phase and Quadrature (IQ) modulator and demodulator are usually used as transmitter (TX) and receiver (RX), respectively. For Digital-to-Analog Converter (DAC) and Analog-to-Digital Converter (ADC) limited systems, such as multi-giga-hertz bandwidth millimeter-wave systems, using analog modulator and demodulator is still a low power and l

  14. Physical exercise on serum electrolytes and acid base balance in Mangalarga Marchador horses submitted to cavalcade of 4, 8 and 20km

    Directory of Open Access Journals (Sweden)

    Jessica Martins Linhares

    Full Text Available ABSTRACT: Acid-base and electrolyte disorders have been described in horses associated during and after exercise. The aim of the present study was to evaluate the effect of cavalcade competition on the acid-base and hydroelectrolytic balance in Mangalarga Marchador horses. For this purpose, 15 geldings, 6.2 ± 1.2 years old and clinically healthy, were distributed into three groups of five animals each. Horses were trained to take part in cavalcade competitions. Animals were submitted to cavalcade along 4km (G4, 8km (G8, and 20km (G20 at mean speeds of 15km h-1, 12km h-1, and 12km h-1, respectively. From each horse, venous blood samples were collected before exercise (T0 and immediately after (T1 cavalcade. Bicarbonate ion (HCO3-, pH, partial pressure of carbon dioxide (pCO2, partial pressure of oxygen (pO2, base excess (BE, hematocrit (Hct, sodium (Na+, potassium (K+, chloride (Cl- and lactate were determined. The variables pH, pO2 and pCO2 were corrected in function of rectal temperature of each animal. Blood samples were analyzed for acid-base balance, as well as biochemical and electrolyte parameters using an i-STAT analyzer. Significant (P<0.05 increase in Hct, Na+, pH, HCO3 - and BE were observed after cavalcade in G20 group. Decrease (P<0.05 in K+ and Cl- were also observed in G20 animals after cavalcade (T1. Changes in the acid-base balance and hydroelectrolytic profile of the Mangalarga Marchador after cavalcade of 20km resulted in hypochloremic metabolic alkalosis. The 20km cavalcade induced significant hydroelectrolytic and acid-base imbalances in Mangalarga Marchador horses.

  15. AllelicImbalance: An R/ bioconductor package for detecting, managing, and visualizing allele expression imbalance data from RNA sequencing

    DEFF Research Database (Denmark)

    Gådin, Jesper R.; van't Hooft, Ferdinand M.; Eriksson, Per

    2015-01-01

    Background: One aspect in which RNA sequencing is more valuable than microarray-based methods is the ability to examine the allelic imbalance of the expression of a gene. This process is often a complex task that entails quality control, alignment, and the counting of reads over heterozygous single......-nucleotide polymorphisms. Allelic imbalance analysis is subject to technical biases, due to differences in the sequences of the measured alleles. Flexible bioinformatics tools are needed to ease the workflow while retaining as much RNA sequencing information as possible throughout the analysis to detect and address...... the possible biases. Results: We present AllelicImblance, a software program that is designed to detect, manage, and visualize allelic imbalances comprehensively. The purpose of this software is to allow users to pose genetic questions in any RNA sequencing experiment quickly, enhancing the general utility...

  16. Factors That Promote Gender Imbalance in the Teaching of Science ...

    African Journals Online (AJOL)

    This research was carried out to investigate factors that promote gender imbalance in the teaching of science/mathematics Fifty (50) Public Secondary and Primary Schools were selected randomly for the study. A total of one thousand (1000) teachers were used for the study comprising 400 males and 600 females. A twenty ...

  17. KRAS Allelic Imbalance: Strengths and Weaknesses in Numbers.

    Science.gov (United States)

    Doherty, Gary J; Kerr, Emma M; Martins, Carla P

    2017-05-01

    The identification of therapeutic vulnerabilities in mutant KRAS tumors has proven difficult to achieve. Burgess and colleagues recently reported in Cell that mutant/wild-type Kras allelic dosage determines clonal fitness and MEK inhibitor sensitivity in a leukemia model, demonstrating that KRAS allelic imbalance is likely an important and overlooked variable. Copyright © 2017 Elsevier Ltd. All rights reserved.

  18. Labor Markets in Imbalance: Review of Qualitative Evidence.

    Science.gov (United States)

    Medoff, James L.; Wiener, Jonathan B.

    Recent statistical investigations indicate that labor market imbalance has increased during the past decade and has had important deleterious effects on the nation's inflation and productivity growth records. A growing difficulty in filling skilled jobs at a given unemployment rate is reflected. Business community analysts attribute the growing…

  19. Gender Power Imbalance on Women's Capacity to Negotiate Self ...

    African Journals Online (AJOL)

    FOMCS2

    African Health Sciences Vol 5 No 3 September 2005. 188 ... Objectives: To examine the influence of gender power imbalance and other ... of South Africa and Botswana, the study used descriptive statistics and logistic regression to reveal a number of gender related ...... states, politicians, sports figures, and other celebrities,.

  20. A mathematical model of blood-interstitial acid-base balance: application to dilution acidosis and acid-base status.

    Science.gov (United States)

    Wolf, Matthew B; Deland, Edward C

    2011-04-01

    We developed mathematical models that predict equilibrium distribution of water and electrolytes (proteins and simple ions), metabolites, and other species between plasma and erythrocyte fluids (blood) and interstitial fluid. The models use physicochemical principles of electroneutrality in a fluid compartment and osmotic equilibrium between compartments and transmembrane Donnan relationships for mobile species. Across the erythrocyte membrane, the significant mobile species Cl⁻ is assumed to reach electrochemical equilibrium, whereas Na(+) and K(+) distributions are away from equilibrium because of the Na(+)/K(+) pump, but movement from this steady state is restricted because of their effective short-term impermeability. Across the capillary membrane separating plasma and interstitial fluid, Na(+), K(+), Ca²(+), Mg²(+), Cl⁻, and H(+) are mobile and establish Donnan equilibrium distribution ratios. In each compartment, attainment of equilibrium by carbonates, phosphates, proteins, and metabolites is determined by their reactions with H(+). These relationships produce the recognized exchange of Cl(-) and bicarbonate across the erythrocyte membrane. The blood submodel was validated by its close predictions of in vitro experimental data, blood pH, pH-dependent ratio of H(+), Cl⁻, and HCO₃⁻ concentrations in erythrocytes to that in plasma, and blood hematocrit. The blood-interstitial model was validated against available in vivo laboratory data from humans with respiratory acid-base disorders. Model predictions were used to gain understanding of the important acid-base disorder caused by addition of saline solutions. Blood model results were used as a basis for estimating errors in base excess predictions in blood by the traditional approach of Siggaard-Andersen (acid-base status) and more recent approaches by others using measured blood pH and Pco₂ values. Blood-interstitial model predictions were also used as a basis for assessing prediction errors of

  1. Genomic imbalances in pediatric patients with chronic kidney disease.

    Science.gov (United States)

    Verbitsky, Miguel; Sanna-Cherchi, Simone; Fasel, David A; Levy, Brynn; Kiryluk, Krzysztof; Wuttke, Matthias; Abraham, Alison G; Kaskel, Frederick; Köttgen, Anna; Warady, Bradley A; Furth, Susan L; Wong, Craig S; Gharavi, Ali G

    2015-05-01

    There is frequent uncertainty in the identification of specific etiologies of chronic kidney disease (CKD) in children. Recent studies indicate that chromosomal microarrays can identify rare genomic imbalances that can clarify the etiology of neurodevelopmental and cardiac disorders in children; however, the contribution of unsuspected genomic imbalance to the incidence of pediatric CKD is unknown. We performed chromosomal microarrays to detect genomic imbalances in children enrolled in the Chronic Kidney Disease in Children (CKiD) prospective cohort study, a longitudinal prospective multiethnic observational study of North American children with mild to moderate CKD. Patients with clinically detectable syndromic disease were excluded from evaluation. We compared 419 unrelated children enrolled in CKiD to multiethnic cohorts of 21,575 children and adults that had undergone microarray genotyping for studies unrelated to CKD. We identified diagnostic copy number disorders in 31 children with CKD (7.4% of the cohort). We detected 10 known pathogenic genomic disorders, including the 17q12 deletion HNF1 homeobox B (HNF1B) and triple X syndromes in 19 of 419 unrelated CKiD cases as compared with 98 of 21,575 control individuals (OR 10.8, P = 6.1 × 10⁻²⁰). In an additional 12 CKiD cases, we identified 12 likely pathogenic genomic imbalances that would be considered reportable in a clinical setting. These genomic imbalances were evenly distributed among patients diagnosed with congenital and noncongenital forms of CKD. In the vast majority of these cases, the genomic lesion was unsuspected based on the clinical assessment and either reclassified the disease or provided information that might have triggered additional clinical care, such as evaluation for metabolic or neuropsychiatric disease. A substantial proportion of children with CKD have an unsuspected genomic imbalance, suggesting genomic disorders as a risk factor for common forms of pediatric nephropathy

  2. Zero balance ultrafiltration (Z-BUF) in blood-primed CRRT circuits achieves electrolyte and acid-base homeostasis prior to patient connection.

    Science.gov (United States)

    Hackbarth, Richard M; Eding, Dawn; Gianoli Smith, Carla; Koch, Ada; Sanfilippo, Dominic J; Bunchman, Timothy E

    2005-09-01

    Infants requiring CRRT present a unique challenge due to the large circuit volume to blood volume ratio. Blood priming is often used, but some patients can become unstable during the initiation of CRRT due to electrolyte and acid-base imbalance. We postulated that using Z-BUF we could normalize electrolytes and improve the acid base status of the prime prior to patient connection. To test this we set up a circuit using the Baxter BM-25 CRRT pump, a polysulfone or AN-69 membrane, and a three-way stopcock. The circuit was primed with a 60/40 mix of expired autologous donor pRBCs and 5% albumin. The modalities of CVVH, CVVHD, and CVVHDF were compared for relative efficacy. Electrolytes, lactate, pH, cytokines (TNF-alpha, IL-1beta, bradykinin, and IL-6) were measured. Plasma hemoglobin levels were also measured before and after the Z-BUF procedure. Bradykinin production and elimination in AN-69 membrane circuits were assessed. All lab values equilibrated by 35 minutes. All CRRT modalities were equally efficacious for Z-BUF. Cytokine production or significant hemolysis was not found. In addition, no bradykinin accumulation occurred in AN-69 membrane-containing circuits. We conclude that Z-BUF is a simple and effective way to normalize electrolyte and acid-base status in the CRRT circuit when blood priming is required.

  3. Developing nucleic acid-based electrical detection systems.

    Science.gov (United States)

    Gabig-Ciminska, Magdalena

    2006-03-02

    Development of nucleic acid-based detection systems is the main focus of many research groups and high technology companies. The enormous work done in this field is particularly due to the broad versatility and variety of these sensing devices. From optical to electrical systems, from label-dependent to label-free approaches, from single to multi-analyte and array formats, this wide range of possibilities makes the research field very diversified and competitive. New challenges and requirements for an ideal detector suitable for nucleic acid analysis include high sensitivity and high specificity protocol that can be completed in a relatively short time offering at the same time low detection limit. Moreover, systems that can be miniaturized and automated present a significant advantage over conventional technology, especially if detection is needed in the field. Electrical system technology for nucleic acid-based detection is an enabling mode for making miniaturized to micro- and nanometer scale bio-monitoring devices via the fusion of modern micro- and nanofabrication technology and molecular biotechnology. The electrical biosensors that rely on the conversion of the Watson-Crick base-pair recognition event into a useful electrical signal are advancing rapidly, and recently are receiving much attention as a valuable tool for microbial pathogen detection. Pathogens may pose a serious threat to humans, animal and plants, thus their detection and analysis is a significant element of public health. Although different conventional methods for detection of pathogenic microorganisms and their toxins exist and are currently being applied, improvements of molecular-based detection methodologies have changed these traditional detection techniques and introduced a new era of rapid, miniaturized and automated electrical chip detection technologies into pathogen identification sector. In this review some developments and current directions in nucleic acid-based electrical

  4. History of medical understanding and misunderstanding of Acid base balance.

    Science.gov (United States)

    Aiken, Christopher Geoffrey Alexander

    2013-09-01

    To establish how controversies in understanding acid base balance arose, the literature on acid base balance was reviewed from 1909, when Henderson described how the neutral reaction of blood is determined by carbonic and organic acids being in equilibrium with an excess of mineral bases over mineral acids. From 1914 to 1930, Van Slyke and others established our acid base principles. They recognised that carbonic acid converts into bicarbonate all non-volatile mineral bases not bound by mineral acids and determined therefore that bicarbonate represents the alkaline reserve of the body and should be a physiological constant. They showed that standard bicarbonate is a good measure of acidosis caused by increased production or decreased elimination of organic acids. However, they recognised that bicarbonate improved low plasma bicarbonate but not high urine acid excretion in diabetic ketoacidosis, and that increasing pCO2 caused chloride to shift into cells raising plasma titratable alkali. Both indicate that minerals influence pH. In 1945 Darrow showed that hyperchloraemic metabolic acidosis in preterm infants fed milk with 5.7 mmol of chloride and 2.0 mmol of sodium per 100 kcal was caused by retention of chloride in excess of sodium. Similar findings were made but not recognised in later studies of metabolic acidosis in preterm infants. Shohl in 1921 and Kildeberg in 1978 presented the theory that carbonic and organic acids are neutralised by mineral base, where mineral base is the excess of mineral cations over anions and organic acid is the difference between mineral base, bicarbonate and protein anion. The degree of metabolic acidosis measured as base excess is determined by deviation in both mineral base and organic acid from normal.

  5. Acid-Base Balance in Uremic Rats with Vascular Calcification

    Directory of Open Access Journals (Sweden)

    Alan Peralta-Ramírez

    2014-07-01

    Full Text Available Background/Aims: Vascular calcification (VC, a major complication in humans and animals with chronic kidney disease (CKD, is influenced by changes in acid-base balance. The purpose of this study was to describe the acid-base balance in uremic rats with VC and to correlate the parameters that define acid-base equilibrium with VC. Methods: Twenty-two rats with CKD induced by 5/6 nephrectomy (5/6 Nx and 10 nonuremic control rats were studied. Results: The 5/6 Nx rats showed extensive VC as evidenced by a high aortic calcium (9.2 ± 1.7 mg/g of tissue and phosphorus (20.6 ± 4.9 mg/g of tissue content. Uremic rats had an increased pH level (7.57 ± 0.03 as a consequence of both respiratory (PaCO2 = 28.4 ± 2.1 mm Hg and, to a lesser degree, metabolic (base excess = 4.1 ± 1 mmol/l derangements. A high positive correlation between both anion gap (AG and strong ion difference (SID with aortic calcium (AG: r = 0.604, p = 0.02; SID: r = 0.647, p = 0.01 and with aortic phosphorus (AG: r = 0.684, p = 0.007; SID: r = 0.785, p = 0.01 was detected. Conclusions: In an experimental model of uremic rats, VC showed high positive correlation with AG and SID.

  6. Acid-base properties of Baltic Sea dissolved organic matter

    Science.gov (United States)

    Hammer, Karoline; Schneider, Bernd; Kuliński, Karol; Schulz-Bull, Detlef E.

    2017-09-01

    Calculations related to the marine CO2 system that are based on alkalinity data may be strongly biased if the contributions of organic compounds are ignored. In coastal seas, concentrations of dissolved organic matter (DOM) are frequently high and alkalinity from inorganic compounds is low. In this study, based on measurements of total alkalinity, total CO2, and pH, we determined the organic alkalinity, Aorg, in water from the central Baltic Sea. The maximum Aorg measured in the surface mixed layer during the spring bloom was > 50 μmol/kg-SW but the Aorg decreased with depth and approached zero below the permanent halocline. This behavior could be attributed to the decreased pH of deeper water layers. The data were used to calculate the bulk dissociation constant, KDOM, for marine DOM and the fraction f of dissolved organic carbon (DOC) that acts as a carrier for acid-base functional groups. The p KDOM (7.27) agreed well with the value (7.34) previously estimated in a preliminary study of organic alkalinity in the Baltic Sea. The fraction of carbon atoms carrying acid-base groups was 17% and was somewhat higher than previously reported (12%). Spike experiments performed using artificial seawater and three different humic/fulvic substances tested whether the acid-base properties of these substances explain the results of our field study. Specifically, Aorg was determined at different concentrations (DOC) of the added humic/fulvic substances. The relationship between Aorg and the DOC concentrations indicated that humic/fulvic substances are more acidic (p KDOM < 6.5) than the bulk DOC natural occurring in the Baltic Sea.

  7. Developing nucleic acid-based electrical detection systems

    Directory of Open Access Journals (Sweden)

    Gabig-Ciminska Magdalena

    2006-03-01

    Full Text Available Abstract Development of nucleic acid-based detection systems is the main focus of many research groups and high technology companies. The enormous work done in this field is particularly due to the broad versatility and variety of these sensing devices. From optical to electrical systems, from label-dependent to label-free approaches, from single to multi-analyte and array formats, this wide range of possibilities makes the research field very diversified and competitive. New challenges and requirements for an ideal detector suitable for nucleic acid analysis include high sensitivity and high specificity protocol that can be completed in a relatively short time offering at the same time low detection limit. Moreover, systems that can be miniaturized and automated present a significant advantage over conventional technology, especially if detection is needed in the field. Electrical system technology for nucleic acid-based detection is an enabling mode for making miniaturized to micro- and nanometer scale bio-monitoring devices via the fusion of modern micro- and nanofabrication technology and molecular biotechnology. The electrical biosensors that rely on the conversion of the Watson-Crick base-pair recognition event into a useful electrical signal are advancing rapidly, and recently are receiving much attention as a valuable tool for microbial pathogen detection. Pathogens may pose a serious threat to humans, animal and plants, thus their detection and analysis is a significant element of public health. Although different conventional methods for detection of pathogenic microorganisms and their toxins exist and are currently being applied, improvements of molecular-based detection methodologies have changed these traditional detection techniques and introduced a new era of rapid, miniaturized and automated electrical chip detection technologies into pathogen identification sector. In this review some developments and current directions in

  8. Developing nucleic acid-based electrical detection systems

    Science.gov (United States)

    Gabig-Ciminska, Magdalena

    2006-01-01

    Development of nucleic acid-based detection systems is the main focus of many research groups and high technology companies. The enormous work done in this field is particularly due to the broad versatility and variety of these sensing devices. From optical to electrical systems, from label-dependent to label-free approaches, from single to multi-analyte and array formats, this wide range of possibilities makes the research field very diversified and competitive. New challenges and requirements for an ideal detector suitable for nucleic acid analysis include high sensitivity and high specificity protocol that can be completed in a relatively short time offering at the same time low detection limit. Moreover, systems that can be miniaturized and automated present a significant advantage over conventional technology, especially if detection is needed in the field. Electrical system technology for nucleic acid-based detection is an enabling mode for making miniaturized to micro- and nanometer scale bio-monitoring devices via the fusion of modern micro- and nanofabrication technology and molecular biotechnology. The electrical biosensors that rely on the conversion of the Watson-Crick base-pair recognition event into a useful electrical signal are advancing rapidly, and recently are receiving much attention as a valuable tool for microbial pathogen detection. Pathogens may pose a serious threat to humans, animal and plants, thus their detection and analysis is a significant element of public health. Although different conventional methods for detection of pathogenic microorganisms and their toxins exist and are currently being applied, improvements of molecular-based detection methodologies have changed these traditional detection techniques and introduced a new era of rapid, miniaturized and automated electrical chip detection technologies into pathogen identification sector. In this review some developments and current directions in nucleic acid-based electrical

  9. Boronic acid-based autoligation of nucleic acids

    DEFF Research Database (Denmark)

    Barbeyron, R.; Vasseur, J.-J.; Smietana, M.

    2013-01-01

    Abstract: The development of synthetic systems displaying dynamic and adaptive characteristics is a formidable challenge with wide applications from biotechnology to therapeutics. Recently, we described a dynamic and programmable nucleic acid-based system relying on the formation of reversible...... boronate internucleosidic linkages. The DNA- or RNA-templated system comprises a 5′-ended boronic acid probe connecting a 3′-ended ribonucleosidic oligonucleotide partner. To explore the dominant factors that control the reversible linkage, we synthesized a series of 3′-end modified ribonucleotidic strands...

  10. Advances in nucleic acid-based diagnostics of bacterial infections

    DEFF Research Database (Denmark)

    Barken, Kim Bundvig; Haagensen, Janus Anders Juul; Tolker-Nielsen, Tim

    2007-01-01

    Methods for rapid detection of infectious bacteria and antimicrobial-resistant pathogens have evolved significantly over the last decade. Many of the new procedures are nucleic acid-based and replace conventional diagnostic methods like culturing which is time consuming especially with fastidious...... of these pathogens is important to isolate patients and prevent further spreading of the diseases. Newly developed diagnostic procedures are superior with respect to turnaround time, sensitivity and specificity. Methods like multiplex real time PCR and different array-based technologies offer the possibility...

  11. Stewart's quantitative acid-base chemistry: applications in biology and medicine.

    Science.gov (United States)

    Fencl, V; Leith, D E

    1993-01-01

    We review P.A. Stewart's quantitative approach to acid-base chemistry, starting with its historical context. We outline its implications for cellular and membrane processes in acid-base physiology; discuss its contributions to the understanding and analysis of acid-base phenomena; show how it can be applied in clinical problems; and propose a classification of clinical acid-base disturbances based on this general approach.

  12. Acid-base Balance in Acute Gastrointestinal Bleeding*

    Science.gov (United States)

    Northfield, T. C.; Kirby, B. J.; Tattersfield, Anne E.

    1971-01-01

    Acid-base balance has been studied in 21 patients with acute upper gastrointestinal bleeding. A low plasma bicarbonate concentration was found in nine patients, accompanied in each case by a base deficit of more than 3 mEq/litre, indicating a metabolic acidosis. Three patients had a low blood pH. Hyperlactataemia appeared to be a major cause of the acidosis. This was not accompanied by a raised blood pyruvate concentration. The hyperlactataemia could not be accounted for on the basis of hyperventilation, intravenous infusion of dextrose, or arterial hypoxaemia. Before blood transfusion it was most pronounced in patients who were clinically shocked, suggesting that it may have resulted from poor tissue perfusion and anaerobic glycolysis. Blood transfusion resulted in a rise in lactate concentration in seven patients who were not clinically shocked, and failed to reverse a severe uncompensated acidosis in a patient who was clinically shocked. These effects of blood transfusion are probably due to the fact that red blood cells in stored bank blood, with added acid-citrate-dextrose solution, metabolize the dextrose anaerobically to lactic acid. Monitoring of acid-base balance is recommended in patients with acute gastrointestinal bleeding who are clinically shocked. A metabolic acidosis can then be corrected with intravenous sodium bicarbonate. PMID:5313902

  13. Influence of diet on acid-base balance.

    Science.gov (United States)

    Remer, T

    2000-01-01

    It is well established that diet and certain food components have a clear impact on acid-base balance. For adults, the following factors are involved: 1) the chemical composition of foods (i.e., their content of protein, chloride, phosphorus, sodium, potassium, calcium, and magnesium), 2) the different intestinal absorption rates of the relevant nutrients, 3) the metabolic generation of sulfate from sulfur-containing amino acids, 4) the grade of dissociation of phosphorus at the physiologic pH of 7.4, and 5) the ionic valence of calcium and magnesium. All these factors allow us to estimate the potential renal acid load (PRAL) of any given food or diet. The PRAL (calculated for a 24-hour period), together with a relatively constant daily amount of urinary excreted organic acids (in healthy subjects proportional to body surface area or body weight), yields the daily net acid excretion. This article provides an overview of the current concepts of diet influences on acid-base balance and also focuses on the underlying physiologic and biochemical basis as well as on relevant clinical implications.

  14. 78 FR 36698 - Microbiology Devices; Reclassification of Nucleic Acid-Based Systems for Mycobacterium tuberculosis

    Science.gov (United States)

    2013-06-19

    ... Nucleic Acid-Based Systems for Mycobacterium tuberculosis Complex in Respiratory Specimens AGENCY: Food...) is proposing to reclassify nucleic acid-based in vitro diagnostic devices for the detection of... Controls Guideline: Nucleic Acid-Based In Vitro Diagnostic Devices for the Detection of Mycobacterium...

  15. How Do Undergraduate Students Conceptualize Acid-Base Chemistry? Measurement of a Concept Progression

    Science.gov (United States)

    Romine, William L.; Todd, Amber N.; Clark, Travis B.

    2016-01-01

    We developed and validated a new instrument, called "Measuring Concept progressions in Acid-Base chemistry" (MCAB) and used it to better understand the progression of undergraduate students' understandings about acid-base chemistry. Items were developed based on an existing learning progression for acid-base chemistry. We used the Rasch…

  16. Acid-base interactions in microbial adhesion to hexadecane and chloroform

    NARCIS (Netherlands)

    Bos, R; Busscher, HJ; Geertsema-Doornbusch, GI; Van Der Mei, HC; Mittal, KL

    2000-01-01

    Acid-base interactions play an important role in adhesion, including microbial adhesion to surfaces. Qualitatively acid-base interactions in microbial adhesion can be demonstrated by comparing adhesion to hexadecane (a negatively charged interface in aqueous solutions, unable to exert acid-base

  17. Down syndrome and the complexity of genome dosage imbalance.

    Science.gov (United States)

    Antonarakis, Stylianos E

    2017-03-01

    Down syndrome (also known as trisomy 21) is the model human phenotype for all genomic gain dosage imbalances, including microduplications. The functional genomic exploration of the post-sequencing years of chromosome 21, and the generation of numerous cellular and mouse models, have provided an unprecedented opportunity to decipher the molecular consequences of genome dosage imbalance. Studies of Down syndrome could provide knowledge far beyond the well-known characteristics of intellectual disability and dysmorphic features, as several other important features, including congenital heart defects, early ageing, Alzheimer disease and childhood leukaemia, are also part of the Down syndrome phenotypic spectrum. The elucidation of the molecular mechanisms that cause or modify the risk for different Down syndrome phenotypes could lead to the introduction of previously unimaginable therapeutic options.

  18. Modified Mahalanobis Taguchi System for Imbalance Data Classification

    Directory of Open Access Journals (Sweden)

    Mahmoud El-Banna

    2017-01-01

    Full Text Available The Mahalanobis Taguchi System (MTS is considered one of the most promising binary classification algorithms to handle imbalance data. Unfortunately, MTS lacks a method for determining an efficient threshold for the binary classification. In this paper, a nonlinear optimization model is formulated based on minimizing the distance between MTS Receiver Operating Characteristics (ROC curve and the theoretical optimal point named Modified Mahalanobis Taguchi System (MMTS. To validate the MMTS classification efficacy, it has been benchmarked with Support Vector Machines (SVMs, Naive Bayes (NB, Probabilistic Mahalanobis Taguchi Systems (PTM, Synthetic Minority Oversampling Technique (SMOTE, Adaptive Conformal Transformation (ACT, Kernel Boundary Alignment (KBA, Hidden Naive Bayes (HNB, and other improved Naive Bayes algorithms. MMTS outperforms the benchmarked algorithms especially when the imbalance ratio is greater than 400. A real life case study on manufacturing sector is used to demonstrate the applicability of the proposed model and to compare its performance with Mahalanobis Genetic Algorithm (MGA.

  19. KNEE ISOKINETIC TORQUE IMBALANCE IN FEMALE FUTSAL PLAYERS

    Directory of Open Access Journals (Sweden)

    Ana Carolina de Mello Alves Rodrigues

    Full Text Available ABSTRACT Introduction: The specificity of sports training can lead to muscle specialization with a possible change in the natural hamstring/quadriceps torque ratio (HQ ratio, constituting a risk factor for muscle injury at the joint angles in which muscle imbalance may impair dynamic stability. Objective: The aim was to evaluate the torque distribution of the hamstrings and quadriceps and the HQ ratio throughout the range of motion in order to identify possible muscle imbalances at the knee of female futsal athletes. Methods: Nineteen amateur female futsal athletes had their dominant limb HQ ratio evaluated in a series of five maximum repetitions of flexion/extension of the knee at 180°/second in the total joint range of motion (30° to 80°. The peak flexor and extensor torque and the HQ ratio (% were compared each 5° of knee motion using one-way repeated measures ANOVA and Tukey’s post hoc test (p<0.05 to determine the joint angles that present muscular imbalance. Results: Quadriceps torque was higher than 50° to 60° of knee flexion, while hamstrings torque was higher than 55° to 65°. The HQ ratio presented lower values than 30° to 45° of knee flexion and four athletes presented values lower than 60%, which may represent a risk of injury. However, the HQ ratio calculated by the peak torque showed only one athlete with less than 60%. Conclusion: The HQ ratio analyzed throughout the knee range of motion allowed identifying muscle imbalance at specific joint angles in female futsal players.

  20. Evidence for charge imbalance waves in phase-slip centers

    Science.gov (United States)

    Kadin, A. M.; Varmazis, C.; Lukens, J. E.

    1981-08-01

    We have examined the I-V characteristics of superconducting phase-slip centers (PSCs) located in the middle of narrow In channels. Features in dV/dI can be associated with resonances in charge imbalance waves driven by the PSC, as suggested by the model of Kadin, Smith and Skocpol. The velocity and temperature dependence of the waves thus inferred are in rough accord with theoretical predictions.

  1. Analysis of Regional Imbalance of E-commerce in China

    OpenAIRE

    Wenjing Cai; Wei Song; ShuLiang Zhao

    2013-01-01

    With the rapid development of knowledge economy in the 21st century, e-commerce is undoubtedly a more popular topic, with high efficiency and low cost in all areas. However, regional imbalance of e-commerce is a new problem in China. In this paper, we present an explanation from eight perspectives to analyze the causes of this phenomenon: economic level, Internet penetration, government policy, credit system, logistics, enterprise participation, talent, and customers’ attitude. Based on analy...

  2. Systemic Redox Imbalance in Chronic Kidney Disease: A Systematic Review

    Directory of Open Access Journals (Sweden)

    Konstantina P. Poulianiti

    2016-01-01

    Full Text Available Patients with chronic kidney disease (CKD experience imbalance between oxygen reactive species (ROS production and antioxidant defenses leading to cell and tissue damage. However, it remains unclear at which stage of renal insufficiency the redox imbalance becomes more profound. The aim of this systematic review was to provide an update on recent advances in our understanding of how the redox status changes in the progression of renal disease from predialysis stages 1 to 4 to end stage 5 and whether the various treatments and dialysis modalities influence the redox balance. A systematic review was conducted searching PubMed and Scopus by using the Cochrane and PRISMA guidelines. In total, thirty-nine studies met the inclusion criteria and were reviewed. Even from an early stage, imbalance in redox status is evident and as the kidney function worsens it becomes more profound. Hemodialysis therapy per se seems to negatively influence the redox status by the elevation of lipid peroxidation markers, protein carbonylation, and impairing erythrocyte antioxidant defense. However, other dialysis modalities do not so far appear to confer advantages. Supplementation with antioxidants might assist and should be considered as an early intervention to halt premature atherogenesis development at an early stage of CKD.

  3. Money and age in schools: Bullying and power imbalances.

    Science.gov (United States)

    Chaux, Enrique; Castellanos, Melisa

    2015-05-01

    School bullying continues to be a serious problem around the world. Thus, it seems crucial to clearly identify the risk factors associated with being a victim or a bully. The current study focused in particular on the role that age and socio-economic differences between classmates could play on bullying. Logistic and multilevel analyses were conducted using data from 53,316 5th and 9th grade students from a representative sample of public and private Colombian schools. Higher age and better family socio-economic conditions than classmates were risk factors associated with being a bully, while younger age and poorer socio-economic conditions than classmates were associated with being a victim of bullying. Coming from authoritarian families or violent neighborhoods, and supporting beliefs legitimizing aggression, were also associated with bullying and victimization. Empathy was negatively associated with being a bully, and in some cases positively associated with being a victim. The results highlight the need to take into account possible sources of power imbalances, such as age and socio-economic differences among classmates, when seeking to prevent bullying. In particular, interventions focused on peer group dynamics might contribute to avoid power imbalances or to prevent power imbalances from becoming power abuse. Aggr. Behav. 41:280-293, 2015. © 2014 Wiley Periodicals, Inc. © 2014 Wiley Periodicals, Inc.

  4. Positional Nystagmus in Patients Evaluated for Dizziness and Imbalance

    Directory of Open Access Journals (Sweden)

    Richard A. Roberts

    2016-01-01

    Full Text Available There is variability in the literature regarding the presence of positional nystagmus in healthy participants with reportedly normal vestibular and central nervous system function. This ranges from 7.5% to 88% and raises an important clinical question. If 88% of healthy participants have positional nystagmus then how is the clinician to interpret the presence of positional nystagmus in a patient presenting with dizziness and/or disequilibrium? The primary purpose of this investigation was to examine the prevalence and characteristics of positional nystagmus in patients evaluated specifically for dizziness and imbalance. Data was collected using retrospective chart review. 200 charts were randomly selected from all patients seen for evaluation of dizziness and imbalance over a period of eight months. Clinicians independently reviewed the data from positional testing for each chart. Nystagmus was present if there was a clear slow and fast phase component and there were three beats in a 10 s time window. Nystagmus direction and intensity data were collected. Results indicate positional nystagmus is present in 10.5% to 21% of patients evaluated for dizziness and imbalance. Use of liberal criteria for determining presence of positional nystagmus (i.e., 3 beats in 20 sec may account for higher prevalence rates across other studies.

  5. Yule-generated trees constrained by node imbalance.

    Science.gov (United States)

    Disanto, Filippo; Schlizio, Anna; Wiehe, Thomas

    2013-11-01

    The Yule process generates a class of binary trees which is fundamental to population genetic models and other applications in evolutionary biology. In this paper, we introduce a family of sub-classes of ranked trees, called Ω-trees, which are characterized by imbalance of internal nodes. The degree of imbalance is defined by an integer 0 ≤ ω. For caterpillars, the extreme case of unbalanced trees, ω = 0. Under models of neutral evolution, for instance the Yule model, trees with small ω are unlikely to occur by chance. Indeed, imbalance can be a signature of permanent selection pressure, such as observable in the genealogies of certain pathogens. From a mathematical point of view it is interesting to observe that the space of Ω-trees maintains several statistical invariants although it is drastically reduced in size compared to the space of unconstrained Yule trees. Using generating functions, we study here some basic combinatorial properties of Ω-trees. We focus on the distribution of the number of subtrees with two leaves. We show that expectation and variance of this distribution match those for unconstrained trees already for very small values of ω. Copyright © 2013 Elsevier Inc. All rights reserved.

  6. Imbalance between abstract and concrete repetitive thinking modes in schizophrenia.

    Science.gov (United States)

    Maurage, Pierre; Philippot, Pierre; Grynberg, Delphine; Leleux, Dominique; Delatte, Benoît; Mangelinckx, Camille; Belge, Jan-Baptist; Constant, Eric

    2017-10-01

    Repetitive thoughts can be divided in two modes: abstract/analytic (decontextualized and dysfunctional) and concrete/experiential (problem-focused and adaptive). They constitute a transdiagnostic process involved in many psychopathological states but have received little attention in schizophrenia, as earlier studies only indexed increased ruminations (related to dysfunctional repetitive thoughts) without jointly exploring both modes. This study explored the two repetitive thinking modes, beyond ruminations, to determine their imbalance in schizophrenia. Thirty stabilized patients with schizophrenia and 30 matched controls completed the Repetitive Response Scale and the Mini Cambridge-Exeter Repetitive Thought Scale, both measuring repetitive thinking modes. Complementary measures related to schizophrenic symptomatology, depression and anxiety were also conducted. Compared to controls, patients with schizophrenia presented an imbalance between repetitive thinking modes, with increased abstract/analytic and reduced concrete/experiential thoughts, even after controlling for comorbidities. Schizophrenia is associated with stronger dysfunctional repetitive thoughts (i.e. abstract thinking) and impaired ability to efficiently use repetitive thinking for current problem-solving (i.e. concrete thinking). This imbalance confirms the double-faced nature of repetitive thinking modes, whose influence on schizophrenia's symptomatology should be further investigated. The present results also claim for evaluating these processes in clinical settings and for rehabilitating the balance between opposite repetitive thinking modes. Copyright © 2017 Elsevier Inc. All rights reserved.

  7. Consensus-based Distributed Control for Accurate Reactive, Harmonic and Imbalance Power Sharing in Microgrids

    DEFF Research Database (Denmark)

    Zhou, Jianguo; Kim, Sunghyok; Zhang, Huaguang

    2017-01-01

    This paper investigates the issue of accurate reactive, harmonic and imbalance power sharing in a microgrid. Harmonic and imbalance droop controllers are developed to proportionally share the harmonic power and the imbalance power among distributed generation (DG) units and improve the voltage qu...

  8. Prevalence and distribution of muscle-imbalance in the human body ...

    African Journals Online (AJOL)

    The phenomenon of muscle imbalance is pandemic, and may contribute to problems such as poor posture, low back pain. Significant is the fact that muscle imbalance may influence the motor patterning process. Key words: Muscle imbalance, low back pain, posture, malposture, withdrawal response. (Af. J. Physical, Health ...

  9. The Role of Grade Sensitivity in Explaining the Gender Imbalance in Undergraduate Economics

    Science.gov (United States)

    Rask, Kevin; Tiefenthaler, Jill

    2008-01-01

    There is a gender imbalance in undergraduate economics departments with most departments educating a strong majority of young men. This imbalance has led many economists to ponder the question of why relatively few women choose to take courses and major in economics. Our hypothesis is that the gender imbalance in undergraduate economics,…

  10. Acid-base transport in pancreas-new challenges

    DEFF Research Database (Denmark)

    Novak, Ivana; Haanes, Kristian Agmund; Wang, Jing

    2013-01-01

    Along the gastrointestinal tract a number of epithelia contribute with acid or basic secretions in order to aid digestive processes. The stomach and pancreas are the most extreme examples of acid (H+) and base (HCO-3) transporters, respectively. Nevertheless, they share the same challenges...... of transporting acid and bases across epithelia and effectively regulating their intracellular pH. In this review, we will make use of comparative physiology to enlighten the cellular mechanisms of pancreatic HCO-3 and fluid secretion, which is still challenging physiologists. Some of the novel transporters...... to consider in pancreas are the proton pumps (H-K-ATPases), as well as the calcium-activated K and Cl channels, such as K3.1 and TMEM16A/ANO1. Local regulators, such as purinergic signaling, fine-tune, and coordinate pancreatic secretion. Lastly, we speculate whether dys-regulation of acid-base transport...

  11. Role of Pendrin in Acid-base Balance

    Science.gov (United States)

    Chang, Jae Hyun

    2009-01-01

    Pendrin (SLC26A4) is a Na+-independent Cl-/HCO3- exchanger which is expressed in the apical membranes of type B and non-A, non-B intercalated cells within the distal convoluted tubule, the connecting tubule, and the cortical collecting duct. In those segments it mediates HCO3- secretion and chloride (Cl-) absorption. In mice, no renal abnormalities are observed under basal conditions, and individuals with genetic disruption of the pendrin (SLC26A4) gene (Pendred syndrome) have normal acid-base balance. In contrast, there are definite differences under conditions wherein the transporter is stimulated. In animal studies, pendrin (SLC26A4) is upregulated with aldosterone analogues, Cl- restriction, and metabolic alkalosis, and is down-regulated with Cl loading and metabolic acidosis, independently. However, the exact role of pendrin in humans has not been established to date, and further examinations are necessary. PMID:21468181

  12. Boronic acid-based chemical sensors for saccharides.

    Science.gov (United States)

    Zhang, Xiao-Tai; Liu, Guang-Jian; Ning, Zhang-Wei; Xing, Guo-Wen

    2017-11-27

    During the past decades, the interaction between boronic acids-functionalized sensors and saccharides is of great interest in the frontier domain of the interdiscipline concerning both biology and chemistry. Various boronic acid-based sensing systems have been developed to detect saccharides and corresponding derivatives in vitro as well as in vivo, which embrace unimolecular sensors, two-component sensing ensembles, functional assemblies, and boronic acid-loaded nanomaterials or surfaces. New sensing strategies emerge in endlessly with excellent selectivity and sensitivity. In this review, several typical sensing systems were introduced and some promising examples were highlighted to enable the deep insight of saccharides sensing on the basis of boronic acids. Copyright © 2017 Elsevier Ltd. All rights reserved.

  13. Evaluating Interest in Acids-Bases: Development of an Acid-Base Interest Scale (ABIS) and Assessment of Pre-Service Science Teachers' Interest

    Science.gov (United States)

    Çiçek, Ö.; Ilhan, N.

    2017-01-01

    Students are more likely to be successful in topics they are interested in than others. This study aims to develop an Acid-Base Interest Scale (ABIS) and subsequently evaluate the interest of pre-service science teachers in acids-bases according to gender, years at the university, type of high school the pre-service science teachers attended, and…

  14. Regulation of Acid-Base Balance in Chronic Kidney Disease.

    Science.gov (United States)

    Nagami, Glenn T; Hamm, L Lee

    2017-09-01

    The kidneys play a major role in the regulation of acid-base balance by reabsorbing bicarbonate filtered by the glomeruli and excreting titratable acids and ammonia into the urine. In CKD, with declining kidney function, acid retention and metabolic acidosis occur, but the extent of acid retention depends not only on the degree of kidney impairment but also on the dietary acid load. Acid retention can occur even when the serum bicarbonate level is apparently normal. With reduced kidney function, acid transport processes in the surviving nephrons are augmented but as disease progresses ammonia excretion and, in some individuals, the ability to reabsorb bicarbonate falls, whereas titratable acid excretion is preserved until kidney function is severely impaired. Urinary ammonia levels are used to gauge the renal response to acid loads and are best assessed by direct measurement of urinary ammonia levels rather than by indirect assessments. In individuals with acidosis from CKD, an inappropriately low degree of ammonia excretion points to the pathogenic role of impaired urinary acid excretion. The presence of a normal bicarbonate level in CKD complicates the interpretation of the urinary ammonia excretion as such individuals could be in acid-base balance or could be retaining acid without manifesting a low bicarbonate level. At this time, the decision to give bicarbonate supplementation in CKD is reserved for those with a bicarbonate level of 22 mEq/L, but because of potential harm of overtreatment, supplementation should be adjusted to maintain a bicarbonate level of <26 mEq/L. Published by Elsevier Inc.

  15. Effect of mineralocorticoids on acid-base balance.

    Science.gov (United States)

    Wagner, Carsten A

    2014-01-01

    Aldosterone is classically associated with the regulation of salt and potassium homeostasis but has also profound effects on acid-base balance. During acidosis, circulating aldosterone levels are increased and the hormone acts in concert with angiotensin II and other factors to stimulate renal acid excretion. Pharmacological blockade of aldosterone action as well as inherited or acquired syndromes of impaired aldosterone release or action impair the renal response to acid loading and cause hyperkalemic renal tubular acidosis. The mineralocorticoid receptor (MR) mediating the genomic effects of aldosterone is expressed in all cells of the distal nephron including all subtypes of intercalated cells. In acid-secretory type A intercalated cells, aldosterone stimulates proton secretion into urine, whereas in non-type A intercalated cells, aldosterone increases the activity of the luminal anion exchanger pendrin stimulating bicarbonate secretion and chloride reabsorption. Aldosterone has also stimulatory effects on proton secretion that may be mediated by a non-genomic pathway. In addition, aldosterone indirectly stimulates renal acid excretion by enhancing sodium reabsorption through the epithelial sodium channel ENaC. Increased sodium reabsorption enhances the lumen-negative transepithelial voltage that facilitates proton secretion by neighboring intercalated cells. This indirect coupling of sodium reabsorption and proton secretion is thought to underlie the fludrocortisone-furosemide test for maximal urinary acidification in patients with suspected distal renal tubular acidosis. In patients with CKD, acidosis-induced aldosterone may contribute to progression of kidney disease. In summary, aldosterone is a powerful regulator of renal acid excretion required for normal acid-base balance. © 2014 S. Karger AG, Basel.

  16. Time-Variation of Imbalance of Order Book in Foreign Exchange Market

    Science.gov (United States)

    Sueshige, Takumi; Kanazawa, Kiyoshi; Takayasu, Hideki; Takayasu, Misako

    The time-variation of the limit order book is studied in terms of the imbalance of the bid and ask sides for foreign exchange markets. We first introduce a set of variables quantifying the imbalance between the bid and ask orders, and study the probability distribution of the imbalance to show its time-variation. We also suggest an approximate Gaussian fit for the imbalance distributions for cross-sectional views. This result implies the localization tendency of the order book imbalance around the Gaussian peak.

  17. The importance of the ionic product for water to understand the physiology of the acid-base balance in humans.

    Science.gov (United States)

    Adeva-Andany, María M; Carneiro-Freire, Natalia; Donapetry-García, Cristóbal; Rañal-Muíño, Eva; López-Pereiro, Yosua

    2014-01-01

    Human plasma is an aqueous solution that has to abide by chemical rules such as the principle of electrical neutrality and the constancy of the ionic product for water. These rules define the acid-base balance in the human body. According to the electroneutrality principle, plasma has to be electrically neutral and the sum of its cations equals the sum of its anions. In addition, the ionic product for water has to be constant. Therefore, the plasma concentration of hydrogen ions depends on the plasma ionic composition. Variations in the concentration of plasma ions that alter the relative proportion of anions and cations predictably lead to a change in the plasma concentration of hydrogen ions by driving adaptive adjustments in water ionization that allow plasma electroneutrality while maintaining constant the ionic product for water. The accumulation of plasma anions out of proportion of cations induces an electrical imbalance compensated by a fall of hydroxide ions that brings about a rise in hydrogen ions (acidosis). By contrast, the deficiency of chloride relative to sodium generates plasma alkalosis by increasing hydroxide ions. The adjustment of plasma bicarbonate concentration to these changes is an important compensatory mechanism that protects plasma pH from severe deviations.

  18. The Importance of the Ionic Product for Water to Understand the Physiology of the Acid-Base Balance in Humans

    Directory of Open Access Journals (Sweden)

    María M. Adeva-Andany

    2014-01-01

    Full Text Available Human plasma is an aqueous solution that has to abide by chemical rules such as the principle of electrical neutrality and the constancy of the ionic product for water. These rules define the acid-base balance in the human body. According to the electroneutrality principle, plasma has to be electrically neutral and the sum of its cations equals the sum of its anions. In addition, the ionic product for water has to be constant. Therefore, the plasma concentration of hydrogen ions depends on the plasma ionic composition. Variations in the concentration of plasma ions that alter the relative proportion of anions and cations predictably lead to a change in the plasma concentration of hydrogen ions by driving adaptive adjustments in water ionization that allow plasma electroneutrality while maintaining constant the ionic product for water. The accumulation of plasma anions out of proportion of cations induces an electrical imbalance compensated by a fall of hydroxide ions that brings about a rise in hydrogen ions (acidosis. By contrast, the deficiency of chloride relative to sodium generates plasma alkalosis by increasing hydroxide ions. The adjustment of plasma bicarbonate concentration to these changes is an important compensatory mechanism that protects plasma pH from severe deviations.

  19. Policy and organizational implications of gender imbalance in the NHS.

    Science.gov (United States)

    Miller, Karen

    2007-01-01

    The purpose of the paper is to examine the policy and organizational implications of gender imbalance in management, which research suggests exists in the NHS. The research in this paper involved a qualitative approach with an analysis of elite interviews conducted with a non-random sample of officials involved in health policy and interviews with a random sample of senior managers in NHS Scotland. The research formed part of a larger study, which explored the enablers and inhibitors to female career progression in various Scottish sectors. The paper finds that gender imbalance in management exists in the NHS. This is manifested in a masculine organizational context, leadership and policy decision-making process, which have implications for female career advancement opportunities and subsequently access to macro policy decisions. The paper involved a sample (30 percent) of senior managers and examined policy processes in NHS Scotland. To improve the external validity of the findings further research should be conducted in NHS organizations in England and Wales. The findings in the paper suggest that gender imbalance in management and a masculine organizational context and leadership style within the NHS create a less than conducive environment for female employees. This has practical implications in terms of levels of part-time employment, career progression and attrition rates. The paper adds to the debate of gender and organizational studies by examining the health sector, which has high levels of female employment but low levels of female representation at senior management levels. The paper therefore adds to an often-neglected area of study, women in leadership and senior managerial positions. The paper is original in its approach by examining the micro and meso organizational dimensions which impact on women's ability to influence macro health policy.

  20. Is severe electrolyte imbalance a contraindication for heart transplant?

    Science.gov (United States)

    Mir Mohammad Sadeghi, Mohsen; Behdad Mehr, Gholamreza; Mir Mohammad Sadeghi, Amir; Mir Mohammad Sadeghi, Pouya; Samani, Shahin; Mansourian, Soheila

    2012-02-01

    Owing to the increasing numbers of patients with end-stage congestive heart failure awaiting heart transplant and the limited number of suitable donor organs, a decrease in stringency of donor criteria has become widely accepted over the last decade. Here, we present a case of a heart donor with severe electrolyte imbalance, specifically severe hypokalemia, and severe hypernatremia. Despite this, heart transplant was a success, and the recipient was discharged from the hospital in good general condition. We recommend further study of this issue with a larger sample size.

  1. Western Interconnection Energy Imbalance Market Status and Prospects (Presentation)

    Energy Technology Data Exchange (ETDEWEB)

    Milligan, M.; Kirby, B.; King, J.; Beuning, S.

    2011-10-01

    This presentation describes how a new wholesale electricity market for energy imbalance ancillary services could be implemented and operated. Some conclusions of this presentation are: (1) Method for calculating additional reserve requirements due to wind and solar production; (2) EIM results in substantial reduction in reserves requirements and ramping demand; (3) Reduced participation reduces benefits for all but reduces the benefits to non-participants the most; (4) Full participation leads to maximum benefit across the Western Interconnection, up to 42% of total reserve requirement; and (5) Regional EIM implementations have smaller but substantial benefits.

  2. Water-wire catalysis in photoinduced acid-base reactions.

    Science.gov (United States)

    Kwon, Oh-Hoon; Mohammed, Omar F

    2012-07-07

    The pronounced ability of water to form a hyperdense hydrogen (H)-bond network among itself is at the heart of its exceptional properties. Due to the unique H-bonding capability and amphoteric nature, water is not only a passive medium, but also behaves as an active participant in many chemical and biological reactions. Here, we reveal the catalytic role of a short water wire, composed of two (or three) water molecules, in model aqueous acid-base reactions synthesizing 7-hydroxyquinoline derivatives. Utilizing femtosecond-resolved fluorescence spectroscopy, we tracked the trajectories of excited-state proton transfer and discovered that proton hopping along the water wire accomplishes the reaction more efficiently compared to the transfer occurring with bulk water clusters. Our finding suggests that the directionality of the proton movements along the charge-gradient H-bond network may be a key element for long-distance proton translocation in biological systems, as the H-bond networks wiring acidic and basic sites distal to each other can provide a shortcut for a proton in searching a global minimum on a complex energy landscape to its destination.

  3. The Acid-Base balance history (Part I

    Directory of Open Access Journals (Sweden)

    Mario Tarantino

    2007-08-01

    Full Text Available In the History of Medicine, the Acid-Base balance is unusual in that it has undergone constant evolution, not merely and not so much as a result of the progress of knowledge in physiological and physiopathological and clinical fields - which is common to all fields of Medical Science, but rather in relation to its very biochemical foundations, as was demonstrated by P. Stewart’s recent critical review and the reviews of J. Corey and J.A. Kellum, which are still valid today - and this is rather unusual. Although it started centuries ago, the history of the acidbase balance has experienced a slow and difficult evolution, and modern concepts almost exploded a couple of decades into the 20th century. It is therefore with even greater wonder and admiration that we look back on the pioneering intuitions of scholars such as R. Boyle, J.B. van Helmont and A.L. Lavoisier, to mention but a few of the scientists who laid the foundations for current knowledge in this fascinating chapter of physiology and clinical practice that belongs transversally to all medical and clinical disciplines.

  4. Acid-base machines: electrical work from neutralization reactions.

    Science.gov (United States)

    Lima, Gilberto; Morais, William G; Gomes, Wellington J A S; Huguenin, Fritz

    2017-11-29

    We have developed an electrochemical system that performs electrical work due to changes in alkaline ion and proton activities associated with acidic solution neutralization. This system can be used to treat wastewater, contributing to sustainable growth. The system includes an electrochemical machine that operates between an acidic and a basic reservoir to produce work in cycles comprising four stages: two isothermal ionic insertion/de-insertion steps and two steps involving acid and base injection. On the basis of the mixing free energy associated with the reaction free energy, we have developed the thermodynamic formalism by considering reversible electrochemical processes to determine the maximum work performed by this acid-base machine and the efficiency. Electrochemical methods in the time and frequency domains helped in investigating the kinetics of sodium ions and proton insertion in host matrices consisting of copper hexacyanoferrate and phosphomolybdic acid, respectively, to improve our understanding of the factors underlying dissipation as a function of pH and pNa. The full cell composed of these insertion electrodes was used as a proof of concept. It performed a maximum work of 26.4 kJ per mol of electro-inserted ion from HCl solution neutralization with the addition of NaOH, to simulate acidic wastewater treatment in a profitable and sustainable way.

  5. Acid-base transport in pancreas – new challenges

    Directory of Open Access Journals (Sweden)

    Ivana eNovak

    2013-12-01

    Full Text Available Along the gastrointestinal tract a number of epithelia contribute with acid or basic secretions in order to aid digestive processes. The stomach and pancreas are the most extreme examples of acid (H+ and base (HCO3- transporters, respectively. Nevertheless, they share the same challenges of transporting acid and bases across epithelia and effectively regulating their intracellular pH. In this review, we will make use of comparative physiology to enlighten the cellular mechanisms of pancreatic HCO3- and fluid secretion, which is still challenging physiologists. Some of the novel transporters to consider in pancreas are the proton pumps (H+-K+-ATPases, as well as the calcium-activated K+ and Cl- channels, such as KCa3.1 and TMEM16A/ANO1. Local regulators, such as purinergic signalling, fine-tune and coordinate pancreatic secretion. Lastly, we speculate whether dys-regulation of acid-base transport contributes to pancreatic diseases including cystic fibrosis, pancreatitis and cancer.

  6. Hypobaric Hypoxia Imbalances Mitochondrial Dynamics in Rat Brain Hippocampus

    Directory of Open Access Journals (Sweden)

    Khushbu Jain

    2015-01-01

    Full Text Available Brain is predominantly susceptible to oxidative stress and mitochondrial dysfunction during hypobaric hypoxia, and therefore undergoes neurodegeneration due to energy crisis. Evidences illustrate a high degree of association for mitochondrial fusion/fission imbalance and mitochondrial dysfunction. Mitochondrial fusion/fission is a recently reported dynamic mechanism which frequently occurs among cellular mitochondrial network. Hence, the study investigated the temporal alteration and involvement of abnormal mitochondrial dynamics (fusion/fission along with disturbed mitochondrial functionality during chronic exposure to hypobaric hypoxia (HH. The Sprague-Dawley rats were exposed to simulated high altitude equivalent to 25000 ft for 3, 7, 14, 21, and 28 days. Mitochondrial morphology, distribution within neurons, enzyme activity of respiratory complexes, Δψm, ADP: ATP, and expression of fission/fusion key proteins were determined. Results demonstrated HH induced alteration in mitochondrial morphology by damaged, small mitochondria observed in neurons with disturbance of mitochondrial functionality and reduced mitochondrial density in neuronal processes manifested by excessive mitochondrial fragmentation (fission and decreased mitochondrial fusion as compared to unexposed rat brain hippocampus. The study suggested that imbalance in mitochondrial dynamics is one of the noteworthy mechanisms occurring in hippocampal neurons during HH insult.

  7. Quantification of the effect of energy imbalance on bodyweight

    Science.gov (United States)

    Hall, Kevin D; Sacks, Gary; Chandramohan, Dhruva; Chow, Carson C; Wang, Y Claire; Gortmaker, Steven L; Swinburn, Boyd A

    2013-01-01

    Obesity interventions can result in weight loss, but accurate prediction of the bodyweight time course requires properly accounting for dynamic energy imbalances. In this report, we describe a mathematical modelling approach to adult human metabolism that simulates energy expenditure adaptations during weight loss. We also present a web-based simulator for prediction of weight change dynamics. We show that the bodyweight response to a change of energy intake is slow, with half times of about 1 year. Furthermore, adults with greater adiposity have a larger expected weight loss for the same change of energy intake, and to reach their steady-state weight will take longer than it would for those with less initial body fat. Using a population-averaged model, we calculated the energy-balance dynamics corresponding to the development of the US adult obesity epidemic. A small persistent average daily energy imbalance gap between intake and expenditure of about 30 kJ per day underlies the observed average weight gain. However, energy intake must have risen to keep pace with increased expenditure associated with increased weight. The average increase of energy intake needed to sustain the increased weight (the maintenance energy gap) has amounted to about 0·9 MJ per day and quantifies the public health challenge to reverse the obesity epidemic. PMID:21872751

  8. Convulsion following gastroenteritis in children without severe electrolyte imbalance.

    Science.gov (United States)

    Ghorashi, Ziaaedin; Nezami, Nariman; Soltani-Ahari, Hassan; Ghorashi, Sona

    2010-01-01

    Three to five million children from among one billion with gastroenteritis die annually worldwide. The etiologic agent in developed countries is viral in 15-60% of cases, while in developing countries, bacteria and parasites are frequently reported as the etiologic factors. Neurologic signs including convulsion are seen in some cases of diarrhea. This study aimed to investigate the etiology, risk factors and short-term prognosis of gastroenteritis with convulsion. During a case-control study, 100 patients with gastroenteritis were enrolled into the case and control groups on the basis of convulsion or no convulsion development, respectively. This study was conducted in Tabriz Children's Hospital from March 2004 to March 2007. The age of patients ranged from 2 months to 7 years, and the groups were age- and sex-matched. Body temperature (BT), severity and type of dehydration, stool exam and culture, past history of convulsion in the patient and first-degree relatives, electrolyte imbalance, and short-term prognosis were studied and compared. The mean weight of groups was not different, while the frequency of fever at the time of admission, past history of febrile convulsion in first-degree relatives and severity of dehydration were significantly higher in the case group (p electrolyte imbalance was observed in patients with gastroenteritis experiencing febrile convulsion.

  9. Gender equity imbalance in electrocardiology: A call to action.

    Science.gov (United States)

    Clarke Whalen, E; Xu, G; Cygankiewicz, I; Bacharova, L; Zareba, W; Steinberg, J S; Tereshchenko, L G; Baranchuk, A

    Despite the increasing number of women entering the medical profession, senior positions and academic productivity in many fields of medicine remain to be men dominated. We explored gender equity in electrocardiology as perceived by recent academic productivity and also active participation (presidencies and board constituents) in both the International Society of Electrocardiology (ISE) and the International Society for Holter and Noninvasive Electrocardiology (ISHNE). Academic productivity was measured by authorship (first and senior) in the Journal of Electrocardiology (JECG) and the Annals of Noninvasive Electrocardiology (ANE) in 2015. The percentage of women ISE and ISHNE Presidents was 5.6% and 0%, respectively. Current women board constituents for each society was 12.1% for ISE, and 9.4% for ISHNE. JECG articles published in 2015 had considerably less women compared to men for both senior (16.3%) and first (25.3%) authorship. ANE articles published in 2015 followed the same trends in gender, having less women compared to men for both senior (9.4%) and first (19.3%) authorship. There is a gender equity imbalance in the field of Electrocardiology. Identifying a gender imbalance is important for understanding reasons behind these trends, and may also help improve gender equity in Electrocardiology. Copyright © 2017 Elsevier Inc. All rights reserved.

  10. Role of intestinal flora imbalance in pathogenesis of pouchitis.

    Science.gov (United States)

    Feng, Xiao-Bo; Jiang, Jun; Li, Min; Wang, Gang; You, Jin-Wei; Zuo, Jian

    2016-08-01

    To discuss the role of intestinal flora imbalance in the pathogenesis of pouchitis. The pouchitis rat model was established and the faeces sample and the mucous membrane sample were collected regularly, in which the bacterial nucleic acids were extracted for quantitative analysis of the intestinal flora in the samples through using the real-time quantitative PCR technique and high energy sequencing technology. The disorder phenomenon of the intestinal flora appeared at the 7th day of the experiment, and the pouchitis was presented at the 21st day of the experiment. At the 31st day of the experiment, compared to control group and non-pouchitis group, the quantity of Bifidobacterium and the Lactobacillus of the pouchitis model rats in the mucous membrane sample and the faeces sample were significantly decreased (P flora in the mucous membrane of pouchitis, the bacterial diversity of non-pouchitis group and control group was significantly higher than that of the pouchitis group (P intestinal flora imbalance is one of the factors that cause the incidence of the pouchitis; this study provides a clue of the pathogenesis and treatment direction of the intestinal inflammatory disease. Copyright © 2016 Hainan Medical College. Production and hosting by Elsevier B.V. All rights reserved.

  11. Evaluation of acid-base disorders in dogs and cats presenting to an emergency room. Part 1: comparison of three methods of acid-base analysis.

    Science.gov (United States)

    Hopper, Kate; Epstein, Steven E; Kass, Philip H; Mellema, Matthew S

    2014-01-01

    To compare the diagnostic performance of the traditional approach to acid-base analysis with the Stewart approach and a semiquantitative approach. Prospective cohort study. University teaching hospital. A total number of 84 dogs and 14 cats presenting to a university teaching hospital emergency room. All dogs and cats in which venous blood samples for acid-base, lactate, and serum biochemical analysis were all collected within 60 minutes of each other, over a 5-month enrollment period. Acid-base analysis was performed using the traditional approach, Stewart approach, and a semiquantitative approach. Traditional acid-base analysis identified respiratory acid-base abnormalities in 14/98 animals and metabolic acid-base abnormalities in 67/98. A mixed disorder of metabolic acidosis and respiratory alkalosis was most common occurring in 29/98 patients. The Stewart approach identified metabolic abnormalities in 82/98 patients; strong ion difference abnormalities were evident in 68/98 cases; an increased strong ion gap acidosis was identified in 49/98 cases; and changes in the quantity of weak acids in 25/98 cases. The semiquantitative approach identified abnormalities in all cases evaluated. Of the 14 patients with a primary respiratory acid-base abnormality, the Stewart approach identified metabolic abnormalities in 9 and the semiquantitative approach found abnormalities in all animals. The physicochemical approaches diagnosed more acid-base abnormalities in this population than the traditional approach although many of the abnormalities identified were small and of unknown clinical relevance. The physicochemical approaches may provide greater insight as to the underlying etiology of abnormalities, which maybe of particular relevance to cases with changes in albumin and/or phosphorus concentration. © Veterinary Emergency and Critical Care Society 2014.

  12. Acid-base thermochemistry of gaseous aliphatic α-aminoacids.

    Science.gov (United States)

    Bouchoux, Guy; Huang, Sihua; Inda, Bhawani Singh

    2011-01-14

    Acid-base thermochemistry of isolated aliphatic amino acids (denoted AAA): glycine, alanine, valine, leucine, isoleucine and proline has been examined theoretically by quantum chemical computations at the G3MP2B3 level. Conformational analysis on neutral, protonated and deprotonated species has been used to identify the lowest energy conformers and to estimate the population of conformers expected to be present at thermal equilibrium at 298 K. Comparison of the G3MP2B3 theoretical proton affinities, PA, and ΔH(acid) with experimental results is shown to be correct if experimental thermochemistry is re-evaluated and adapted to the most recent acidity-basicity scales. From this point of view, a set of evaluated proton affinities of 887, 902, 915, 916, 919 and 941 kJ mol(-1), and a set of evaluated ΔH(acid) of 1433, 1430, 1423, 1423, 1422 and 1426 kJ mol(-1), is proposed for glycine, alanine, valine, leucine, isoleucine and proline, respectively. Correlations with structural parameters (Taft's σ(α) polarizability parameter and molecular size) suggest that polarizability of the side chain is the major origin of the increase in PA and decrease in ΔH(acid) along the homologous series glycine, alanine, valine and leucine/isoleucine. Heats of formation of gaseous species AAA, AAAH(+) and [AAA-H](-) were computed at the G3MP2B3 level. The present study provides previously unavailable Δ(f)H°(298) for the ionized species AAAH(+) and [AAA-H](-). Comparison with Benson's estimate, and correlation with molecular size, show that several experimental Δ(f)H°(298) values of neutral or gaseous AAA might be erroneous.

  13. Pathophysiological aspect of metabolic acid-base disorders

    Directory of Open Access Journals (Sweden)

    Nešović-Ostojić Jelena

    2016-01-01

    Full Text Available Maintaing the arterial pH values (in normal range of 7,35-7,45 is one of the main principles of homeostasis. Regulatory responses, including chemical buffering (extracellular, intracellular, sceletal, the regulation of pCO2 by the respiratory system, and the regulation of [HCO3-] by the kidneys, act in concert to maintain normal arterial pH value. The main extracellular chemical buffer is bicarbonate-carbonic acid buffer system. The kidneys contribute to the regulation of hydrogen (and bicarbonate in body fluids in two ways. Proximal tubules are important in bicarbonate reabsorption and distal tubules excrete hydrogen ion (as ammonium ion or titratable acid. There are four simple acid-base disorders: metabolic acidosis and metabolic alkalosis; respiratory acidosis and respiratory alkalosis. Metabolic acidosis can occur because of an increase in endogenous acid production (such as lactate and ketoacids, loss of bicarbonate (as in diarrhea, or accumulation of endogenous acids (as in renal failure. Metabolic acidosis can also be with high and normal (hyperchloremic metabolic acidosis anion gap. Renal tubular acidosis (RTA is a form of hyperchloremic metabolic acidosis which occurs when the renal damage primarily affects tubular function. The main problem in distal RTA is reduced H+ excretion in distal tubule. Type 2 RTA is also called proximal RTA because the main problem is greatly impaired reabsorption of bicarbonate in proximal tubule. Impaired cation exchange in distal tubule is the main problem in RTA type 4. Metabolic alkalosis occurs as a result of net gain of [HCO3-] or loss of nonvolatile acid from extracellular fluids. Metabolic alkalosis can be associated with reduced or increased extracellular volume.

  14. Polarizable model potential function for nucleic acid bases.

    Science.gov (United States)

    Nakagawa, Setsuko

    2007-07-15

    A polarizable model potential (PMP) function for adenine (A), cytosine (C), guanine (G), thymine (T), and uracil (U) is developed on the basis of ab initio molecular orbital calculations at the MP2/6-31+G* level. The PMP function consists of Coulomb, van der Waals, and polarization terms. The permanent atomic charges of the Coulomb term are determined by using electrostatic potential (ESP) optimization. The multicenter polarizabilities of the polarization term are determined by using polarized one-electron potential (POP) optimization in which the electron density changes induced by a test charge are target. Isotropic and anisotropic polarizabilities are adopted as the multicenter polarizabilities. In the PMP calculations using the optimized parameters, the interaction energies of Watson-Crick type A-T and C-G base pairs were -15.6 and -29.4 kcal/mol, respectively. The interaction energy of Hoogsteen type A-T base pair was -17.8 kcal/mol. These results reproduce well the quantum chemistry calculations at the MP2/6-311++G(3df,2pd) level within the differences of 0.6 kcal/mol. The stacking energies of A-T and C-G were -9.7 and -10.9 kcal/mol. These reproduce well the calculation results at the MP2/6-311++G (2d,2p) level within the differences of 1.3 kcal/mol. The potential energy surfaces of the system in which a sodium ion or a chloride ion is adjacent to the nucleic acid base are calculated. The interaction energies of the PMP function reproduced well the calculation results at the MP2/6-31+G* or MP2/6-311++G(2d,2p) level. The reason why the PMP function reproduces well the high-level quantum mechanical interaction energies is addressed from the viewpoint of each energy terms. Copyright (c) 2007 Wiley Periodicals, Inc.

  15. (20-01) "Order Imbalances and Market Efficiency: Evidence from the Taiwan Stock Exchange"

    OpenAIRE

    Lee, Yi-Tsung; Liu, Yu-Jane; Roll, Richard; Subrahmanyam, Avanidhar

    2001-01-01

    Data from the Taiwan Stock Exchange identify the originator of each submitted order. We study order imbalances categorized by trade size and by investor type, (individuals, domestic institutions, foreign institutions.) Aggregate order imbalances for a given stock are positively autocorrelated from day to day. The persistence in order imbalances is strongest for small foreign institutions and weakest for large individual investors. All investor types are contrarian; they submit excess buy orde...

  16. Effects of specific muscle imbalance improvement training on the balance ability in elite fencers

    OpenAIRE

    Kim, Taewhan; Kil, Sekee; Chung, Jinwook; Moon, Jeheon; Oh, Eunyoung

    2015-01-01

    [Purpose] The lunge Motion that occurs frequently in fencing training and matches results in imbalance of the upper and lower limbs muscles. This research focuses on the improvement of the imbalance that occurs in the national team fencers of the Republic of Korea through specific muscle imbalance improvement training. [Subjects] The subjects of this research were limited to right-handed male fencers. Nine male, right-handed national fencing athletes were selected for this study (4 epee, 5 sa...

  17. Stewart analysis of apparently normal acid-base state in the critically ill

    NARCIS (Netherlands)

    Moviat, M.; Boogaard, M. van den; Intven, F.; Voort, P. van der; Hoeven, H. van der; Pickkers, P.

    2013-01-01

    PURPOSE: This study aimed to describe Stewart parameters in critically ill patients with an apparently normal acid-base state and to determine the incidence of mixed metabolic acid-base disorders in these patients. MATERIALS AND METHODS: We conducted a prospective, observational multicenter study of

  18. Using the Logarithmic Concentration Diagram, Log "C", to Teach Acid-Base Equilibrium

    Science.gov (United States)

    Kovac, Jeffrey

    2012-01-01

    Acid-base equilibrium is one of the most important and most challenging topics in a typical general chemistry course. This article introduces an alternative to the algebraic approach generally used in textbooks, the graphical log "C" method. Log "C" diagrams provide conceptual insight into the behavior of aqueous acid-base systems and allow…

  19. A Comparative Study of French and Turkish Students' Ideas on Acid-Base Reactions

    Science.gov (United States)

    Cokelez, Aytekin

    2010-01-01

    The goal of this comparative study was to determine the knowledge that French and Turkish upper secondary-school students (grades 11 and 12) acquire on the concept of acid-base reactions. Following an examination of the relevant curricula and textbooks in the two countries, 528 students answered six written questions about the acid-base concept.…

  20. Thai Grade 11 Students' Alternative Conceptions for Acid-Base Chemistry

    Science.gov (United States)

    Artdej, Romklao; Ratanaroutai, Thasaneeya; Coll, Richard Kevin; Thongpanchang, Tienthong

    2010-01-01

    This study involved the development of a two-tier diagnostic instrument to assess Thai high school students' understanding of acid-base chemistry. The acid-base diagnostic test (ABDT) comprising 18 items was administered to 55 Grade 11 students in a science and mathematics programme during the second semester of the 2008 academic year. Analysis of…

  1. High School Students' Understanding of Acid-Base Concepts: An Ongoing Challenge for Teachers

    Science.gov (United States)

    Damanhuri, Muhd Ibrahim Muhamad; Treagust, David F.; Won, Mihye; Chandrasegaran, A. L.

    2016-01-01

    Using a quantitative case study design, the "Acids-Bases Chemistry Achievement Test" ("ABCAT") was developed to evaluate the extent to which students in Malaysian secondary schools achieved the intended curriculum on acid-base concepts. Responses were obtained from 260 Form 5 (Grade 11) students from five schools to initially…

  2. Collaborative Strategies for Teaching Common Acid-Base Disorders to Medical Students

    Science.gov (United States)

    Petersen, Marie Warrer; Toksvang, Linea Natalie; Plovsing, Ronni R.; Berg, Ronan M. G.

    2014-01-01

    The ability to recognize and diagnose acid-base disorders is of the utmost importance in the clinical setting. However, it has been the experience of the authors that medical students often have difficulties learning the basic principles of acid-base physiology in the respiratory physiology curriculum, particularly when applying this knowledge to…

  3. Canonical Pedagogical Content Knowledge by Cores for Teaching Acid-Base Chemistry at High School

    Science.gov (United States)

    Alvarado, Clara; Cañada, Florentina; Garritz, Andoni; Mellado, Vicente

    2015-01-01

    The topic of acid-base chemistry is one of the oldest in general chemistry courses and it has been almost continuously in academic discussion. The central purpose of documenting the knowledge and beliefs of a group of ten Mexican teachers with experience in teaching acid-base chemistry in high school was to know how they design, prepare and…

  4. [Dynamics of blood gases and acid-base balance in patients with carbon monoxide acute poisoning].

    Science.gov (United States)

    Polozova, E V; Shilov, V V; Bogachova, A S; Davydova, E V

    2015-01-01

    Evaluation of blood gases and acid-base balance covered patients with carbon monoxide acute poisoning, in accordance with inhalation trauma presence. Evidence is that thermochemical injury of respiratory tract induced severe acid-base dysbalance remaining decompensated for a long time despite the treatment.

  5. Diet-induced modification of the acid-base balance in rats: toxicological implications

    NARCIS (Netherlands)

    Lina, Berend Adriaan Rene

    2004-01-01

    The composition of the diet can strongly affect the acid-base balance of the body. The studies described in this thesis deal with toxicological implications of dietary modulation of the acid-base balance in rats. These studies included 4-wk, 13-wk and 18-month toxicity studies, and a 30-month

  6. Water-Electrolytic and Acid-Base Balance in Critically Ill Patients

    Directory of Open Access Journals (Sweden)

    L. V. Gerasimov

    2008-01-01

    Full Text Available The review deals with some aspects of correction of water-electrolytic and acid-base balance and this problem-associated infusion therapy. It characterizes various electrolytic solutions and considers the efficacy and safety of their use in terms of homeostatic maintenance. Key words: homeostasis, dyshidria, acid-base balance, acidosis, infusion therapy, crystalloid solutions.

  7. Approach to acid-base disorders – a clinical chemistry perspective

    African Journals Online (AJOL)

    Approach to acid-base disorders – a clinical chemistry perspective. Acid-base disorders are frequently encountered in clinical practice and have a significant impact on patient morbidity and mortality. Nicholette M Oosthuizen, MB ChB, FC Path (SA) Chem. Acting Head, Department of Chemical Pathology, University of ...

  8. Mixed acid-base disorder secondary to topiramate use in traumatic brain injury

    Directory of Open Access Journals (Sweden)

    S Golla

    2016-01-01

    Full Text Available We report a case of a man with traumatic brain injury. He was started on to prophylactic topiramate which led to a mixed acid-base disorder. He had severe metabolic acidosis secondary to renal tubular acidification defect and respiratory alkalosis secondary to hyperventilation. Withdrawal of the offending drug led to the prompt resolution of the acid-base disturbance.

  9. Efficient Compensation of Transmitter and Receiver IQ Imbalance in OFDM Systems

    Directory of Open Access Journals (Sweden)

    Tandur Deepaknath

    2010-01-01

    Full Text Available Radio frequency impairments such as in-phase/quadrature-phase (IQ imbalances can result in a severe performance degradation in direct-conversion architecture-based communication systems. In this paper, we consider the case of transmitter and receiver IQ imbalance together with frequency selective channel distortion. The proposed training-based schemes can decouple the compensation of transmitter and receiver IQ imbalance from the compensation of channel distortion in an orthogonal frequency division multiplexing (OFDM systems. The presence of frequency selective channel fading is a requirement for the estimation of IQ imbalance parameters when both transmitter/receiver IQ imbalance are present. However, the proposed schemes are equally applicable over a frequency flat/frequency selective channel when either transmitter or only receiver IQ imbalance is present. Once the transmitter and receiver IQ imbalance parameters are estimated, a standard channel equalizer can be applied to estimate/compensate for the channel distortion. The proposed schemes result in an overall lower training overhead and a lower computational requirement, compared to the joint compensation of transmitter/receiver IQ imbalance and channel distortion. Simulation results demonstrate that the proposed schemes provide a very efficient compensation with performance close to the ideal case without any IQ imbalance.

  10. Redox Imbalance and Viral Infections in Neurodegenerative Diseases

    Directory of Open Access Journals (Sweden)

    Dolores Limongi

    2016-01-01

    Full Text Available Reactive oxygen species (ROS are essential molecules for many physiological functions and act as second messengers in a large variety of tissues. An imbalance in the production and elimination of ROS is associated with human diseases including neurodegenerative disorders. In the last years the notion that neurodegenerative diseases are accompanied by chronic viral infections, which may result in an increase of neurodegenerative diseases progression, emerged. It is known in literature that enhanced viral infection risk, observed during neurodegeneration, is partly due to the increase of ROS accumulation in brain cells. However, the molecular mechanisms of viral infection, occurring during the progression of neurodegeneration, remain unclear. In this review, we discuss the recent knowledge regarding the role of influenza, herpes simplex virus type-1, and retroviruses infection in ROS/RNS-mediated Parkinson’s disease (PD, Alzheimer’s disease (AD, and amyotrophic lateral sclerosis (ALS.

  11. Investigation of Global Imbalances Based on a Gravity Model

    Directory of Open Access Journals (Sweden)

    Hyun-Hoon Lee

    2011-06-01

    Full Text Available Using the US Treasury International Capital (TIC data, this paper attempts to analyze the size and trend of foreign investment in the U.S. in the form of equities, bonds and bank lending during the period of 2001-2007. In addition, this paper assesses the determinants of foreign investment in the U.S., using the financial gravity model which includes an East Asian dummy as an explanatory variable. The results show that most East Asian countries have invested more in the U.S. than the optimal level suggested by the gravity model. Such an over-investment is more evident in long-term bond investment than in equity investment or bank lending. Thus, the results confirm that global imbalance does exist between East Asian countries and the U.S.

  12. Quality control of reconstructed sagittal balance for sagittal imbalance.

    Science.gov (United States)

    Chang, Kao-Wha; Leng, Xiangyang; Zhao, Wenhai; Ching-Wei, Cheng; Chen, Tsung-Chein; Chang, Ku-I; Chen, Yin-Yu

    2011-02-01

    Prospective radiographic study. To investigate the feasibility of controlling quality of reconstructed sagittal balance for sagittal imbalance. Patients with sagittal imbalance cannot walk or stand erect without overwork of musculature because of compromised biomechanical advantage. The result is muscle fatigue and activity-related pain. During reconstructive surgery, restoration of optimal sagittal balance is crucial for obtaining satisfactory clinical results. However, there is no way to control quality of reconstructed sagittal balance before or during surgery. A method was developed to determine the lumbosacral curve in a way that theoretically would bring sagittal balance to an ideal state by calculation and simulation for each patient before surgery and then template rods of the curve and a blueprint were made accordingly for operative procedures. Ninety-four consecutive patients with sagittal imbalance due to lumbar kyphosis were treated for intractable pain and then followed up for a mean of 4.3 years. Radiographs were analyzed before surgery, 2 months after surgery, and at most recent follow-up. The mean estimated values of L1-S1 lordosis, sacral inclination angle, sacrofemoral distance, and distribution of L1-S1 lordosis at the closing-opening wedge osteotomy site and L4-S1 segments were 30.8°, 24.6°, 0 mm, 16.1% (-5°), and 62% (-19°), respectively. The mean reconstructed values were 41.1°, 23.3°, 3.9 mm, 41% (-17°), and 46% (-19°), respectively. There were significant differences between estimated and reconstructed values of L1-S1 lordosis and the percentage of distributions; however, there was no significant difference between the estimated and reconstructed magnitude of L4-S1 lordosis, sacral inclination angle, and sacrofemoral distance. A properly oriented pelvis can be brought nearly directly above the hip axis. The mean sagittal global balance, represented by the distance between the vertical line through the hip axis and sacral promontory

  13. Wet cupping therapy restores sympathovagal imbalances in cardiac rhythm.

    Science.gov (United States)

    Arslan, Müzeyyen; Yeşilçam, Nesibe; Aydin, Duygu; Yüksel, Ramazan; Dane, Senol

    2014-04-01

    A recent study showed that cupping had therapeutic effects in rats with myocardial infarction and cardiac arrhythmias. The current studyaimed to investigate the possible useful effects of cupping therapy on cardiac rhythm in terms of heart rate variability (HRV). Forty healthy participants were included. Classic wet cupping therapy was applied on five points of the back. Recording electrocardiography (to determine HRV) was applied 1 hour before and 1 hour after cupping therapy. All HRV parameters increased after cupping therapy compared with before cupping therapy in healthy persons. These results indicate for the first time in humans that cupping might be cardioprotective. In this study, cupping therapy restored sympathovagal imbalances by stimulating the peripheral nervous system.

  14. A case of myotonic dystrophy with electrolyte imbalance.

    Science.gov (United States)

    Ko, Weon-Jin; Kim, Kwang-Yeol; Kim, So-Mi; Hong, Seung-Jae; Lee, Sang-Hoon; Song, Ran; Yang, Hyung-In; Lee, Yeon-Ah

    2013-07-01

    Type 1 myotonic dystrophy (DM1) is an autosomal-dominant inherited disorder with a multisystem involvement, caused by an abnormal expansion of the CTG sequence of the dystrophic myotonia protein kinase (DMPK) gene. DM1 is a variable multisystem disorder with muscular and nonmuscular abnormalities. Increasingly, endocrine abnormalities, such as gonadal, pancreatic, and adrenal dysfunction are being reported. But, Electrolytes imbalance is a very rare condition in patients with DM1 yet. Herein we present a 42-yr-old Korean male of DM1 with abnormally elevated serum sodium and potassium. The patient had minimum volume of maximally concentrated urine without water loss. It was only cured by normal saline hydration. The cause of hypernatremia was considered by primary hypodipsia. Hyperkalemic conditions such as renal failure, pseudohyperkalemia, cortisol deficiency and hyperkalemic periodic paralysis were excluded. Further endocrine evaluation suggested selective hyperreninemic hypoaldosteronism as a cause of hyperkalemia.

  15. Depersonalization disorder may be related to glutamate receptor activation imbalance.

    Science.gov (United States)

    Pikwer, Andreas

    2011-10-01

    Low-dose ketamine administration mimics, both clinically and on gross neuroimaging, depersonalization disorder. The perceptual effects of ketamine may be due to secondary stimulation of glutamate release and lamotrigine, possibly by inhibited glutamate release, may reduce some of ketamine's so-called dissociative effects. However, lamotrigine does not seem to be useful in the treatment of depersonalization disorder. Glutamate release in prefrontal cortex is increased by subanaesthetic doses of ketamine, resulting in increased inhibition, possibly via intercalated GABAerg cells, of projections from amygdala, affecting structures critically involved in depersonalization. I speculate that, in depersonalization disorder, the increased glutamate activity in prefrontal cortex is due to intrinsic imbalance, resulting in long-term potentiation, at the postsynaptic glutamate receptors on the GABAerg interneurons while the same receptor abnormality at the synapses on the intercalated GABAerg cells of the amygdala result in long-term depression in the case of either normal or high glutamate release. Copyright © 2011 Elsevier Ltd. All rights reserved.

  16. FDI Inflows and Trade Imbalances: Evidence from Developing Asia

    Directory of Open Access Journals (Sweden)

    Thi Anh-Dao Tran

    2014-06-01

    Full Text Available The present paper examines the effects of FDI inflows on external imbalances in the developing and transition countries in Asia during the period 1991-2011. To this end, we extend the conventional trade balance model by reformulating the determinants of exports and imports. Our empirical findings suggest that current FDI inflows increase trade deficits, leading to negative consequences for the host country’s macroeconomic stability. However, the coefficient estimated becomes negative when we lag the FDI variable, implying that FDI inflows worsen the trade balance first and then improve it. We also find that a real depreciation tends to worsen trade balances because the usual Marshall-Lerner constraint is magnified by the import content of exports. Lastly, higher domestic absorption and larger productive capacity in the manufacturing sector improve the trade balance. Thelatter result supports the export-investment nexus, one of the most distinctive features of Asia.

  17. Interaction between Current Imbalance and Magnetization in LHC Cables

    CERN Document Server

    Bottura, L; Kuijper, A; den Ouden, A; ten Haken, B; ten Kate, H H J

    2001-01-01

    The quality of the magnetic field in superconducting accelerator magnets is associated with the properties of the superconducting cable. Current imbalances due to coupling currents DI, as large as 100 A, are induced by spatial variations of the field sweep rate and contact resistances. During injection at a constant field all magnetic field components show a decay behavior. The decay is caused by a diffusion of coupling currents into the whole magnet. This results in a redistribution of the transport current among the strands and causes a demagnetization of the superconducting cable. As soon as the field is ramped up again after the end of injection, the magnetization rapidly recovers from the decay and follows the course of the original hysteresis curve. In order to clarify the interactions between the changes in current and magnetization during injection we performed a number of experiments. A magnetic field with a spatially periodic pattern was applied to a superconducting wire in order to simulate the cou...

  18. Propensity to obesity impacts the neuronal response to energy imbalance

    Directory of Open Access Journals (Sweden)

    Marc-Andre eCornier

    2015-02-01

    Full Text Available The mechanisms responsible for the propensity to gain weight or remain normal weight are poorly understood. The objective of this study was to study the neuronal response to visual food cues during short-term energy imbalance in healthy adults recruited as obesity-resistant (OR or obesity-prone (OP based on self-identification, BMI, and personal/family weight history. 25 OR and 28 OP subjects were studied in underfed (UF and overfed (OF as compared to eucaloric (EU conditions in a randomized crossover design. Each study phase included a 3 day run-in diet, 1 day of controlled feeding (basal energy needs for EU, 40% above/below basal energy needs for OF/UF, and a test day. On the test day fMRI was performed in the acute fed stated (30 minutes after a test meal while subjects viewed images of foods of high hedonic value and neutral non-food objects. Measures of appetite and hormones were also performed before and every 30 minutes after the test meal. UF was associated with significantly increased activation of insula, somatosensory cortex, inferior and medial prefrontal cortex, parahippocampus, precuneus, cingulate and visual cortex in OR. However, UF had no impact in OP. As a result, UF was associated with significantly greater activation, specifically in the insula, inferior prefrontal cortex, and somatosensory cortex in OR as compared to OP. While OF was overall associated with reduced activation of inferior visual cortex, no group interaction was observed with OF. In summary, these findings suggest that individuals resistant to weight gain and obesity are more sensitive to short-term energy imbalance, particularly with UF, than those prone to weight gain. The inability to sense or adapt to changes in energy balance may represent an important mechanism contributing to excess energy intake and risk for obesity.

  19. Metabolic Effects of a Succinic Acid Substrate Antihypoxant

    Directory of Open Access Journals (Sweden)

    B. N. Shakh

    2014-01-01

    Full Text Available The paper discusses promises for clinical use of substrate antihypoxants.Objective: to investigate the efficacy of succinate containing  substrate  antihypoxants  on  systemic  oxygen  consumption,  blood  buffer  capacity,  and  changes  in  the  mixed venous blood level of lactate when they are used in gravely sick patients and victims with marked metabolic posthypoxic disorders.Subjects and methods. The trial enrolled 30 patients and victims who had sustained an episode of severe hypoxia of mixed genesis, the severity of which was evaluated by the APACHE II scale and amounted to 23 to 30 scores with a 46 to 70.3% risk of death. The standard infusion program in this group involved the succinate-containing drug 1.5% reamberin solution  in  a  total  dose  of  800  ml.  A  comparison  group  included  15  patients  who  had  undergone  emergency  extensive surgery for abdominal diseases. 400 ml of 10% glucose solution was used as an infusion medium. Oxygen consumption (VO2ml/min and carbon dioxide production (VCO2ml/min were measured before infusion and monitored for 2 hours. Arterial blood gases and acid-base balance (ABB parameters and mixed venous blood lactate levels were examined. Measurements were made before and 30 minutes after the infusion of reamberin or glucose solution.Results. Infusion of 1.5% reamberin solution was followed by a significant increase in minute oxygen consumption from 281.5±21.2 to 310.4±24.4 ml/min. CO2 production declined (on average, from 223.3±6.5 to 206.5±7.59 ml/min. During infusion of 10% glucose solution, all the patients of the comparison group showed a rise in oxygen consumption from 303.6±33.86 to 443.13±32.1 ml/min, i.e. about 1.5-fold. VCO2 changed similarly. The intravenous infusion of 800 ml of 1.5% reamberin solution raised arterial blood buffer capacity, which was reflected by changes in pH, BE, and HCO3. There was a clear trend for lactate values to drop in the

  20. [Procedural analysis of acid-base balance disorder: case serials in 4 patents].

    Science.gov (United States)

    Ma, Chunyuan; Wang, Guijie

    2017-05-01

    To establish the standardization process of acid-base balance analysis, analyze cases of acid-base balance disorder with the aid of acid-base balance coordinate graph. The acid-base balance theory were reviewed systematically on recent research progress, and the important concepts, definitions, formulas, parameters, regularity and inference in the analysis of acid-base balance were studied. The analysis of acid-base balance disordered processes and steps were figured. The application of acid-base balance coordinate graph in the cases was introduced. The method of "four parameters-four steps" analysis was put forward to analyze the acid-base balance disorders completely. "Four parameters" included pH, arterial partial pressure of carbon dioxide (PaCO2), HCO3- and anion gap (AG). "Four steps" were outlined by following aspects: (1) according to the pH, PaCO2 and HCO3-, the primary or main types of acid-base balance disorder was determined; (2) primary or main types of acid-base disorder were used to choose the appropriate compensation formula and to determine the presence of double mixed acid-base balance disorder; (3) the primary acid-base balance disorders were divided into two parts: respiratory acidosis or respiratory alkalosis, at the same time, the potential HCO3- should be calculated, the measured HCO3- should be replaced with potential HCO3-, to determine whether there were three mixed acid-base disorders; (4) based on the above analysis the data judged as the simple AG increased-metabolic acidosis was needed to be further analyzed. The ratio of ΔAG↑/ΔHCO3-↓ was also needed to be calculated, to determine whether there was normal AG metabolic acidosis or metabolic alkalosis. In the clinical practice, PaCO2 (as the abscissa) and HCO3- (as the ordinate) were used to establish a rectangular coordinate system, through origin (0, 0) and coordinate point (40, 24) could be a straight line, and all points on the straight line pH were equal to 7.40. The acid-base

  1. A REVIEW ON ACID BASE STATUS IN DAIRY COWS: IMPLICATIONS OF DIETARY CATION-ANION BALANCE

    Directory of Open Access Journals (Sweden)

    D. Afzaal, M. Nisa, M. A. Khan and M. Sarwar

    2004-10-01

    Full Text Available The acid base status of a dairy cow is maintained within a narrow range. The key mechanisms involving blood, cells and lungs, perform this function. Although other minerals have an impact on acid base metabolism, the minerals used in dietary cation-anion balance (DCAB namely sodium (Na, potassium (K and chloride (Cl have the greatest effect. Hence, acid base status implicates other biological functions of dairy cows. Low DCAB prepartum reduces the incidence of milk fever and increases the productivity by simmering down the severity of hypocalcaemia. High DCAB diets have proved to increase dry mater and water intake and production and to mitigate the effects of heat stress.

  2. Homeostatic Imbalance in Epithelial Ducts and Its Role in Carcinogenesis

    Directory of Open Access Journals (Sweden)

    Katarzyna A. Rejniak

    2012-01-01

    Full Text Available An epithelial duct is a well-defined multicellular structure composed of tightly packed cells separating and protecting body compartments that are used for enzyme secretion and its transport across the internal. The structural and functional integrity (homeostasis of such ducts is vital in carrying many life functions (breathing, lactation, production of hormones. However, the processes involved in maintaining the homeostatic balance are not yet fully understood. On the other hand, the loss of epithelial tissue architecture, such as filled lumens or ductal disorganization, are among the first symptoms of the emerging epithelial tumors (carcinomas. Using the previously developed biomechanical model of epithelial ducts: IBCell, we investigated how different signals and mechanical stimuli imposed on individual epithelial cells can impact the homeostatic (imbalance and integrity of the whole epithelial tissue. We provide a link between erroneous responses of individual epithelial cells to specific signals and the emerging ductal morphologies characteristic for preinvasive cancers observed in pathology specimens, or characteristic for multicellular structures arising from mutated cells cultured in vitro. We summarize our finding in terms of altered properties of epithelial cell polarization, and discuss the relative importance of various polarization signals on the formation of tumor-like multicellular structures.

  3. A Rare Chromosome 3 Imbalance and Its Clinical Implications

    Directory of Open Access Journals (Sweden)

    Karen Sims

    2012-01-01

    Full Text Available The duplication of chromosome 3q is a rare disorder with varying chromosomal breakpoints and consequently symptoms. Even rarer is the unbalanced outcome from a parental inv(3 resulting in duplicated 3q and a deletion of 3p. Molecular karyotyping should aid in precisely determining the length and breakpoints of the 3q+/3p− so as to better understand a child’s future development and needs. We report a case of an infant male with a 57.5 Mb duplication from 3q23-qter. This patient also has an accompanying 1.7 Mb deletion of 3p26.3. The duplicated segment in this patient encompasses the known critical region of 3q26.3-q27, which is implicated in the previously reported 3q dup syndrome; however, the accompanying 3p26.3 deletion is smaller than the previously reported cases. The clinical phenotype of this patient relates to previously reported cases of 3q+ that may suggest that the accompanying 1.7 Mb heterozygous deletion is not clinically relevant. Taken together, our data has refined the location and extent of the chromosome 3 imbalance, which will aid in better understanding the molecular underpinning of the 3q syndrome.

  4. Electrolyte depletion and osmotic imbalance in amphibians with chytridiomycosis.

    Science.gov (United States)

    Voyles, Jamie; Berger, Lee; Young, Sam; Speare, Rick; Webb, Rebecca; Warner, Jeffrey; Rudd, Donna; Campbell, Ruth; Skerratt, Lee F

    2007-09-14

    Mounting evidence implicates the disease chytridiomycosis, caused by the fungus Batrachochytrium dendrobatidis, in global amphibian declines and extinctions. While the virulence of this disease has been clearly demonstrated, there is, as yet, no mechanistic explanation for how B. dendrobatidis kills amphibians. To investigate the pathology of chytridiomycosis, blood samples were collected from uninfected, aclinically infected and clinically diseased amphibians and analyzed for a wide range of biochemical and hematological parameters. Here, we show that green tree frogs Litoria caerulea with severe chytridiomycosis had reduced plasma osmolality, sodium, potassium, magnesium and chloride concentrations. Stable plasma albumin, hematocrit and urea levels indicated that hydration status was unaffected, signifying depletion of electrolytes from circulation rather than dilution due to increased water uptake. We suggest that B. dendrobatidis kills amphibians by disrupting normal epidermal functioning, leading to osmotic imbalance through loss of electrolytes. Determining how B. dendrobatidis kills amphibians is fundamental to understanding the host-pathogen relationship and thus the population declines attributed to B. dendrobatidis. Understanding the mechanisms of mortality may also explain interspecific variation in susceptibility to chytridiomycosis.

  5. Child underreporting, fertility, and sex ratio imbalance in China.

    Science.gov (United States)

    Goodkind, Daniel

    2011-02-01

    Child underreporting is often neglected in studies of fertility and sex ratio imbalance in China. To improve estimates of these measures, I use intercensal comparisons to identify a rise in underreporting, which followed the increased enforcement and penalization under the birth planning system in 1991. A new triangulation of evidence indicates that about 19% of children at ages 0-4 were unreported in the 2000 census, more than double that of the 1990 census. This evidence contradicts assumptions underlying the fertility estimates of most recent studies. Yet, the analysis also suggests that China's fertility in the late 1990s (and perhaps beyond) was below officially adjusted levels. I then conduct a similar intercensal analysis of sex ratios of births and children, which are the world's highest primarily because of prenatal sex selection. However, given excess underreporting of young daughters, especially pronounced just after 1990, estimated ratios are lower than reported ratios. Sex ratios in areas with a "1.5-child" policy are especially distorted because of excess daughter underreporting, as well as sex-linked stopping rules and other factors, although it is unclear whether such policies increase use of prenatal sex selection. China's sex ratio at birth, once it is standardized by birth order, fell between 2000 and 2005 and showed a continuing excess in urban China, not rural China.

  6. Biomedical Implications of Heavy Metals Induced Imbalances in Redox Systems

    Directory of Open Access Journals (Sweden)

    Bechan Sharma

    2014-01-01

    Full Text Available Several workers have extensively worked out the metal induced toxicity and have reported the toxic and carcinogenic effects of metals in human and animals. It is well known that these metals play a crucial role in facilitating normal biological functions of cells as well. One of the major mechanisms associated with heavy metal toxicity has been attributed to generation of reactive oxygen and nitrogen species, which develops imbalance between the prooxidant elements and the antioxidants (reducing elements in the body. In this process, a shift to the former is termed as oxidative stress. The oxidative stress mediated toxicity of heavy metals involves damage primarily to liver (hepatotoxicity, central nervous system (neurotoxicity, DNA (genotoxicity, and kidney (nephrotoxicity in animals and humans. Heavy metals are reported to impact signaling cascade and associated factors leading to apoptosis. The present review illustrates an account of the current knowledge about the effects of heavy metals (mainly arsenic, lead, mercury, and cadmium induced oxidative stress as well as the possible remedies of metal(s toxicity through natural/synthetic antioxidants, which may render their effects by reducing the concentration of toxic metal(s. This paper primarily concerns the clinicopathological and biomedical implications of heavy metals induced oxidative stress and their toxicity management in mammals.

  7. Biomedical implications of heavy metals induced imbalances in redox systems.

    Science.gov (United States)

    Sharma, Bechan; Singh, Shweta; Siddiqi, Nikhat J

    2014-01-01

    Several workers have extensively worked out the metal induced toxicity and have reported the toxic and carcinogenic effects of metals in human and animals. It is well known that these metals play a crucial role in facilitating normal biological functions of cells as well. One of the major mechanisms associated with heavy metal toxicity has been attributed to generation of reactive oxygen and nitrogen species, which develops imbalance between the prooxidant elements and the antioxidants (reducing elements) in the body. In this process, a shift to the former is termed as oxidative stress. The oxidative stress mediated toxicity of heavy metals involves damage primarily to liver (hepatotoxicity), central nervous system (neurotoxicity), DNA (genotoxicity), and kidney (nephrotoxicity) in animals and humans. Heavy metals are reported to impact signaling cascade and associated factors leading to apoptosis. The present review illustrates an account of the current knowledge about the effects of heavy metals (mainly arsenic, lead, mercury, and cadmium) induced oxidative stress as well as the possible remedies of metal(s) toxicity through natural/synthetic antioxidants, which may render their effects by reducing the concentration of toxic metal(s). This paper primarily concerns the clinicopathological and biomedical implications of heavy metals induced oxidative stress and their toxicity management in mammals.

  8. Appetite regulation in response to sitting and energy imbalance.

    Science.gov (United States)

    Granados, Kirsten; Stephens, Brooke R; Malin, Steven K; Zderic, Theodore W; Hamilton, Marc T; Braun, Barry

    2012-04-01

    The impact of sitting and energy imbalance on appetite and appetite-regulating hormones (acylated ghrelin and leptin) was assessed in response to 1 day of sitting, with and without changes in energy intake. Fourteen men and women completed each of three 24-h conditions: high energy expenditure (standing) with energy balance (STAND), low energy expenditure (sitting) with energy surplus (SIT), and sitting with energy balance (SIT-BAL). Ghrelin, leptin, and appetite were measured in the fasted state and following a standardized meal. In the fasted state, there were no differences among conditions. Following the meal, ghrelin was lower in SIT than in STAND, with no change in appetite. When intake was reduced (SIT-BAL), the decrease in ghrelin when sitting was attenuated, hunger increased, and fullness decreased. SIT led to lower ghrelin concentrations in the men, whereas in the women, leptin increased. SIT-BAL led to an increase in ghrelin in the men but attenuated the leptin response, reduced ghrelin, increased hunger, and decreased fullness in the women. Because a dramatic reduction in energy expenditure was not accompanied by reduced appetite, prolonged sitting may promote excess energy intake, leading to weight gain in both men and women.

  9. Biomedical Implications of Heavy Metals Induced Imbalances in Redox Systems

    Science.gov (United States)

    Singh, Shweta; Siddiqi, Nikhat J.

    2014-01-01

    Several workers have extensively worked out the metal induced toxicity and have reported the toxic and carcinogenic effects of metals in human and animals. It is well known that these metals play a crucial role in facilitating normal biological functions of cells as well. One of the major mechanisms associated with heavy metal toxicity has been attributed to generation of reactive oxygen and nitrogen species, which develops imbalance between the prooxidant elements and the antioxidants (reducing elements) in the body. In this process, a shift to the former is termed as oxidative stress. The oxidative stress mediated toxicity of heavy metals involves damage primarily to liver (hepatotoxicity), central nervous system (neurotoxicity), DNA (genotoxicity), and kidney (nephrotoxicity) in animals and humans. Heavy metals are reported to impact signaling cascade and associated factors leading to apoptosis. The present review illustrates an account of the current knowledge about the effects of heavy metals (mainly arsenic, lead, mercury, and cadmium) induced oxidative stress as well as the possible remedies of metal(s) toxicity through natural/synthetic antioxidants, which may render their effects by reducing the concentration of toxic metal(s). This paper primarily concerns the clinicopathological and biomedical implications of heavy metals induced oxidative stress and their toxicity management in mammals. PMID:25184144

  10. The man-made creators of the imbalance of water in Nature

    Science.gov (United States)

    Shlafman, L. M.; Kontar, V. A.

    2013-12-01

    At 2011 we have described the imbalance of water in Nature as the system [1]. At 2012 we have described water and carbon and the glaciers [2], [3] as creators of the imbalance of Nature. Now we are describing some man-made creators of the imbalance of Nature. The photosynthesis is a powerful creator of the imbalance of Nature. The photosynthesis significantly increases the complexity of the structures and reduces the entropy. Earth's hydrosphere contains water less than it was flowed via photosynthesis. This is an example of the imbalance of involving when the return of water has delayed because water is involved into the processes of life and other processes. People widely use photosynthesis and create not only an additional man-made imbalance of water in Nature, but also the man-made changing the albedo, and a lot of other important parameters of the planet of Earth. All of these processes are significantly imbalanced. The fossil hydrocarbons have accumulated during millions of years, but now are burned. This is an example of the imbalance delay by time. The man-made burning of the hydrocarbons is creating the imbalances of impact or explosive type, because of the burning processes is in millions of times faster than the accumulation processes. Please pay attention to the imbalance of redeployment by places. For example, oil and gas are extracted in one places, and burned in others. During combustion is standing out not only water, but energy, and other components. The temperature in the centers of big cities is always higher and there is dominating the rising air. It pollutes the environment, changes circulations, create greenhouse effect, etc. Other examples of the imbalance of relocation are shown in the production and consumption of food. The irrigation systems transfer water from one place to another. This transfer of water creates a lot of imbalances in change climate, ecosystems, etc in places where water was took and where the water was brought. Usually

  11. Why and How To Teach Acid-Base Reactions without Equilibrium.

    Science.gov (United States)

    Carlton, Terry S.

    1997-01-01

    Recommends an approach to the treatment of acid-base equilibria that involves treating each reaction as either going to completion or not occurring at all. Compares the method with the traditional approach step by step. (DDR)

  12. Efficacy of pretreating oil palm fronds with an acid-base mixture catalyst.

    Science.gov (United States)

    Jung, Young Hoon; Park, Hyun Min; Park, Yong-Cheol; Park, Kyungmoon; Kim, Kyoung Heon

    2017-07-01

    Oil palm fronds are abundant but recalcitrant to chemical pretreatment. Herein, an acid-base mixture was applied as a catalyst to efficiently pretreat oil palm fronds. Optimized conditions for the pretreatment were a 0.1M acidic acid-base mixture and 3min ramping to 190°C and 12min holding. The oil palm fronds pretreated and washed with the acid-base mixture exhibited an enzymatic digestibility of 85% by 15 FPU Accellerase 1000/g glucan after 72h hydrolysis, which was significantly higher than the enzymatic digestibilities obtained by acid or alkali pretreatment alone. This could be attributed to the synergistic actions of the acid and base, producing an 87% glucose recovery with 100% and 40.3% removal of xylan and lignin, respectively, from the solids. Therefore, an acid-base mixture can be a feasible catalyst to deconstruct oil palm fronds for sugar production. Copyright © 2017 Elsevier Ltd. All rights reserved.

  13. Effects of dietary strong acid anion challenge on regulation of acid-base balance in sheep

    National Research Council Canada - National Science Library

    Las, J. E; Odongo, N. E; Lindinger, M. I; AlZahal, O; Shoveller, A. K; Matthews, J. C; McBride, B. W

    2007-01-01

    ...{at}uoguelph.ca The acid-base status of the extracellular fluid is directly affected by the concentrations of strong basic cations and strong acid anions that are absorbed into the bloodstream from the diet...

  14. Recent advances in understanding trans-epithelial acid-base regulation and excretion mechanisms in cephalopods

    OpenAIRE

    Hu, Marian Y.; Hwang, Pung-Pung; Tseng, Yung-Che

    2015-01-01

    Cephalopods have evolved complex sensory systems and an active lifestyle to compete with fish for similar resources in the marine environment. Their highly active lifestyle and their extensive protein metabolism has led to substantial acid-base regulatory abilities enabling these organisms to cope with CO2 induced acid-base disturbances. In convergence to teleost, cephalopods possess an ontogeny-dependent shift in ion-regulatory epithelia with epidermal ionocytes being the major site of embry...

  15. Evaluation of acid-base status in patients admitted to ED-physicochemical vs traditional approaches.

    Science.gov (United States)

    Antonogiannaki, Elvira-Markela; Mitrouska, Ioanna; Amargianitakis, Vassilis; Georgopoulos, Dimitris

    2015-03-01

    The aim of this study is to evaluate the value of physicochemical, base excess (BE), and plasma bicarbonate concentration ([HCO3(-)]) approaches on the assessment of acid-base status in patients presented to the emergency department (ED). Upon presentation at ED, patients whose arterial blood was deemed in need of analysis were studied. Arterial blood gases, serum electrolytes, and proteins were measured and used to derive [HCO3(-)], BE, anion gap (AG), AG adjusted for albumin (AGadj), strong ion difference, strong ion gap (SIG) and SIG corrected for water excess/deficit (SIGcor). In each patient the acid-base status was evaluated using the BE, [HCO3(-)], and physicochemical approaches. A total of 365 patients were studied. Compared with BE (n = 202) and [HCO3(-)] (n = 151), physicochemical approach (n = 279) identified significantly more patients with metabolic acid-base disturbances (P physicochemical approach. The corresponding values with [HCO3(-)] approach were 108 and 95 (88%) patients. When patients with high AGadj were excluded, 44 patients with BE and 67 with [HCO3(-)] approach had normal acid-base status, and most of them exhibited at least 1 acid-base disturbance with the physicochemical approach, whereas 12 and 21 patients, respectively, had high SIGcor. Compared with the BE and [HCO3(-)] methods, the physicochemical approach has a better diagnostic accuracy to identify metabolic acid-base disturbances. Copyright © 2014 Elsevier Inc. All rights reserved.

  16. Quantitative acid-base physiology using the Stewart model. Does it improve our understanding of what is really wrong?

    NARCIS (Netherlands)

    Derksen, R.; Scheffer, G.J.; Hoeven, J.G. van der

    2006-01-01

    Traditional theories of acid-base balance are based on the Henderson-Hasselbalch equation to calculate proton concentration. The recent revival of quantitative acid-base physiology using the Stewart model has increased our understanding of complicated acid-base disorders, but has also led to several

  17. Diagnosis of nutrient imbalances with vector analysis in agroforestry systems.

    Science.gov (United States)

    Isaac, Marney E; Kimaro, Anthony A

    2011-01-01

    Agricultural intensification has had unintended environmental consequences, including increased nutrient leaching and surface runoff and other agrarian-derived pollutants. Improved diagnosis of on-farm nutrient dynamics will have the advantage of increasing yields and will diminish financial and environmental costs. To achieve this, a management support system that allows for site-specific rapid evaluation of nutrient production imbalances and subsequent management prescriptions is needed for agroecological design. Vector diagnosis, a bivariate model to depict changes in yield and nutritional response simultaneously in a single graph, facilitates identification of nutritional status such as growth dilution, deficiency, sufficiency, luxury uptake, and toxicity. Quantitative data from cocoa agroforestry systems and pigeonpea intercropping trials in Ghana and Tanzania, respectively, were re-evaluated with vector analysis. Relative to monoculture, biomass increase in cocoa ( L.) under shade (35-80%) was accompanied by a 17 to 25% decline in P concentration, the most limiting nutrient on this site. Similarly, increasing biomass with declining P concentrations was noted for pigeonpea [ (L). Millsp.] in response to soil moisture availability under intercropping. Although vector analysis depicted nutrient responses, the current vector model does not consider non-nutrient resource effects on growth, such as ameliorated light and soil moisture, which were particularly active in these systems. We revisit and develop vector analysis into a framework for diagnosing nutrient and non-nutrient interactions in agroforestry systems. Such a diagnostic technique advances management decision-making by increasing nutrient precision and reducing environmental issues associated with agrarian-derived soil contamination. American Society of Agronomy, Crop Science Society of America, and Soil Science Society of America.

  18. Copper Imbalances in Ruminants and Humans: Unexpected Common Ground1

    Science.gov (United States)

    Suttle, Neville F.

    2012-01-01

    Ruminants are more vulnerable to copper deficiency than humans because rumen sulfide generation lowers copper availability from forage, increasing the risk of conditions such as swayback in lambs. Molybdenum-rich pastures promote thiomolybdate (TM) synthesis and formation of unabsorbable Cu-TM complexes, turning risk to clinical reality (hypocuprosis). Selection pressures created ruminant species with tolerance of deficiency but vulnerability to copper toxicity in alien environments, such as specific pathogen–free units. By contrast, cases of copper imbalance in humans seemed confined to rare genetic aberrations of copper metabolism. Recent descriptions of human swayback and the exploratory use of TM for the treatment of Wilson’s disease, tumor growth, inflammatory diseases, and Alzheimer’s disease have created unexpected common ground. The incidence of pre–hemolytic copper poisoning in specific pathogen–free lambs was reduced by an infection with Mycobacterium avium that left them more responsive to treatment with TM but vulnerable to long-term copper depletion. Copper requirements in ruminants and humans may need an extra allowance for the “copper cost” of immunity to infection. Residual cuproenzyme inhibition in TM-treated lambs and anomalies in plasma copper composition that appeared to depend on liver copper status raise this question “can chelating capacity be harnessed without inducing copper-deficiency in ruminants or humans?” A model of equilibria between exogenous (TM) and endogenous chelators (e.g., albumin, metallothionein) is used to predict risk of exposure and hypocuprosis; although risk of natural exposure in humans is remote, vulnerability to TM-induced copper deficiency may be high. Biomarkers of TM impact are needed, and copper chaperones for inhibited cuproenzymes are prime candidates. PMID:22983845

  19. Imbalance aware lithography hotspot detection: a deep learning approach

    Science.gov (United States)

    Yang, Haoyu; Luo, Luyang; Su, Jing; Lin, Chenxi; Yu, Bei

    2017-07-01

    With the advancement of very large scale integrated circuits (VLSI) technology nodes, lithographic hotspots become a serious problem that affects manufacture yield. Lithography hotspot detection at the post-OPC stage is imperative to check potential circuit failures when transferring designed patterns onto silicon wafers. Although conventional lithography hotspot detection methods, such as machine learning, have gained satisfactory performance, with the extreme scaling of transistor feature size and layout patterns growing in complexity, conventional methodologies may suffer from performance degradation. For example, manual or ad hoc feature extraction in a machine learning framework may lose important information when predicting potential errors in ultra-large-scale integrated circuit masks. We present a deep convolutional neural network (CNN) that targets representative feature learning in lithography hotspot detection. We carefully analyze the impact and effectiveness of different CNN hyperparameters, through which a hotspot-detection-oriented neural network model is established. Because hotspot patterns are always in the minority in VLSI mask design, the training dataset is highly imbalanced. In this situation, a neural network is no longer reliable, because a trained model with high classification accuracy may still suffer from a high number of false negative results (missing hotspots), which is fatal in hotspot detection problems. To address the imbalance problem, we further apply hotspot upsampling and random-mirror flipping before training the network. Experimental results show that our proposed neural network model achieves comparable or better performance on the ICCAD 2012 contest benchmark compared to state-of-the-art hotspot detectors based on deep or representative machine leaning.

  20. T lymphocyte subset imbalances in patients contribute to ankylosing spondylitis

    Science.gov (United States)

    WANG, CHENGGONG; LIAO, QIANDE; HU, YIHE; ZHONG, DA

    2015-01-01

    Ankylosing spondylitis is a chronic inflammatory rheumatic disease, which is characterized by inflammation of the spine and the sacroiliac joints. To date, the disease etiology remains unclear. In the present study, the correlation of T lymphocyte subset changes with the progression of ankylosing spondylitis was investigated. A total of 55 patients with ankylosing spondylitis (22 severe and 23 mild cases) and 20 healthy individuals were selected. Firstly, the punctured cells in the lesions and the serum were collected, and the lymphocytes and the peripheral blood mononuclear cells were prepared. Secondly, quantitative PCR, ELISA and flow cytometry analyses were carried out to detect the levels of a series of immunoglobulins, complements, helper T cells, cytotoxic T cells, regulatory cells and cytokines. The expression levels of α-globulin, γ-globulin, immunoglobulin (Ig)G, IgA, IgM, serum complement C3, and complement C4 were found to be significantly increased in ankylosing spondylitis patients. In addition, the percentage of Th1 and Th17 cells was found to be significantly higher in the ankylosing spondylitis groups (mild and severe) compared with the healthy individuals. As a result, the Th1/Th2 and Th17/Treg ratios were significantly higher in patients with ankylosing spondylitis. In addition, T lymphocyte subset ratio imbalances contributed to an increased expression of immune mediators, including interferon (IFN)-γ and interleukin (IL)-17A. The mRNA and protein expression levels of IFN-γ and IL-17A were found to be higher in the ankylosing spondylitis groups compared with the control group. The present study provided further evidence on the function and underlying mechanism of T lymphocyte subsets, which may be useful in the diagnosis and treatment of ankylosing spondylitis. PMID:25452811

  1. Salt and water imbalance in chronic heart failure.

    Science.gov (United States)

    Parrinello, Gaspare; Torres, Daniele; Paterna, Salvatore

    2011-10-01

    In chronic heart failure (CHF), neurohumoral systems, which help to maintain circulatory homeostasis, are maladaptive and responsible for disease progression and congestion in the long term. The activation of sympathetic hormones and renin-angiotensin-aldosterone system (RAAS), in addition to non-osmotic vasopressin release, up-regulation of aquoporine 2 and renal sodium transporters, and renal resistance to natriuretic peptide lead to a salt- and water-avid state. A primary decrease in cardiac output and arterial vasodilatation brings about arterial underfilling, which activates neuro-humoral reflexes and systems. The heart disease is the primum movens, but the kidney is the end organ responsible for increased tubular reabsorption of sodium and water. The most important hemodynamic alteration in the kidneys is constriction of glomerular efferent arterioles, which increases intraglomerular pressure and hence glomerular filtration rate. The resulting changes in intrarenal oncotic and hydrostatic pressures promote tubular reabsorption. Over time, a gradually falling glomerular filtration rate, due to CHF progression, medications or chronic kidney injury due to comorbidities, becomes more critical in sodium/water imbalance. Moreover, long-term use of diuretics can lead to a diuretic-resistant state, which necessitates the use of higher doses further activating RAAS, often at the expense of worsening renal function. However, every patient is a case in itself and the general pathophysiology of hydro-saline balance may be different in each subject. A mechanism can prevail over others and the kidney may have different responses to the same diuretic. So, it is necessary to customize each individual's long-term therapy, tailoring medical treatment according to clinical profiles, comorbidities and renal function, introducing active control of body weight by the patient himself, fluid restriction, a less restricted sodium intake, flexibility of diuretic doses, early and

  2. Imbalance aware lithography hotspot detection: a deep learning approach

    Science.gov (United States)

    Yang, Haoyu; Luo, Luyang; Su, Jing; Lin, Chenxi; Yu, Bei

    2017-03-01

    With the advancement of VLSI technology nodes, light diffraction caused lithographic hotspots have become a serious problem affecting manufacture yield. Lithography hotspot detection at the post-OPC stage is imperative to check potential circuit failures when transferring designed patterns onto silicon wafers. Although conventional lithography hotspot detection methods, such as machine learning, have gained satisfactory performance, with extreme scaling of transistor feature size and more and more complicated layout patterns, conventional methodologies may suffer from performance degradation. For example, manual or ad hoc feature extraction in a machine learning framework may lose important information when predicting potential errors in ultra-large-scale integrated circuit masks. In this paper, we present a deep convolutional neural network (CNN) targeting representative feature learning in lithography hotspot detection. We carefully analyze impact and effectiveness of different CNN hyper-parameters, through which a hotspot-detection-oriented neural network model is established. Because hotspot patterns are always minorities in VLSI mask design, the training data set is highly imbalanced. In this situation, a neural network is no longer reliable, because a trained model with high classification accuracy may still suffer from high false negative results (missing hotspots), which is fatal in hotspot detection problems. To address the imbalance problem, we further apply minority upsampling and random-mirror flipping before training the network. Experimental results show that our proposed neural network model achieves highly comparable or better performance on the ICCAD 2012 contest benchmark compared to state-of-the-art hotspot detectors based on deep or representative machine leaning.

  3. Changes in the acid-base balance and lactate concentration in the blood in amateur ultramarathon runners during a 100-km run

    Directory of Open Access Journals (Sweden)

    Z Jastrzębski

    2015-09-01

    Full Text Available The aim of this study was to analyse the acid-base balance and partial pressure of blood gases of participants during a 100-km run. Fourteen experienced amateur ultramarathon runners (age: 43.36±11.83 years; height: 175.29±6.98 cm; weight: 72.12±7.36 kg completed the 100-km run. Blood samples were taken before the run; after 25, 50, 75, and 100 km; and 12 and 24 hours after the run. There were significant differences (p<0.05 between the mean values registered for acid-alkaline balance, buffering alkalies, and current bicarbonate in each segment of the run, especially during the third, fourth, and fifth segments of the run (i.e., between 50 and 100 km, and there were only significant differences associated with buffering alkalies and current bicarbonate during the recovery. However, all the changes were within the physiological norm. A significant decrease in the compressibility of oxygen was observed after 100 km (from 92.80±15.67 to 88.36±13.71 mmHg and continued during the recovery to 75.06±8.60 mmHg 12 h after the run. Also there was a decrease in saturation to a mean value of 93.78±3.10 at 12 h after the run. Generally the amateurs runners are able to adjust their running speed so as not to provoke a significant acid-base imbalance or lactate acid accumulation.

  4. A comparison of intra-operative blood loss and acid-base balance between vasopressor and inotrope strategy during living donor liver transplantation: a randomised, controlled study.

    Science.gov (United States)

    Hong, S H; Park, C S; Jung, H S; Choi, H; Lee, S R; Lee, J; Choi, J H

    2012-10-01

    Administration of vasopressors or inotropes during liver transplant surgery is almost universal, as this procedure is often accompanied by massive haemorrhage, acid-base imbalance, and cardiovascular instability. However, the actual agents that should be used and the choice between a vasopressor and an inotrope strategy are not clear from existing published evidence. In this prospective, randomised, controlled and single-blinded study, we compared the effects of a vasopressor strategy on intra-operative blood loss and acid-base status with those of an inotrope strategy during living donor liver transplantation. Seventy-six adult liver recipients with decompensated cirrhosis were randomly assigned to receive a continuous infusion of either phenylephrine at a dose of 0.3-0.4 μg.kg(-1).min(-1) or dopamine and/or dobutamine at 2-8 μg.kg(-1).min(-1) during surgery. Vascular resistance was higher over time in the phenylephrine group than in the dopamine/dobutamine group. Estimated blood loss was significantly lower in the phenylephrine group than in the dopamine/dobutamine group (mean (SD) 4.5 (1.8) l vs 6.1 (3.4) l, respectively, p=0.011). Patients in the phenylephrine group had lower lactate levels in the late pre-anhepatic and the early anhepatic phase and needed less bicarbonate administration than those in the dopamine/dobutamine group (median (IQR [range]) 40 (0-100 [0-160]) mEq vs 70 (40-163 [0-260]) mEq, respectively, p=0.018). Postoperative clinical outcomes and laboratory-measured hepatic and renal function did not differ between the groups. Increased vascular resistance and reduction of portal blood flow by intra-operative phenylephrine infusion is assumed to decrease the amount of intra-operative bleeding and thereby ameliorate the progression of lactic acidosis during liver transplant surgery. Anaesthesia © 2012 The Association of Anaesthetists of Great Britain and Ireland.

  5. Codigestion of manure and industrial organic waste at centralized biogas plants: process imbalances and limitations

    DEFF Research Database (Denmark)

    Bangsø Nielsen, Henrik; Angelidaki, Irini

    2008-01-01

    The present study focuses on process imbalances in Danish centralized biogas plants treating manure in combination with industrial waste. Collection of process data from various full-scale plants along with a number of interviews showed that imbalances occur frequently. High concentrations...... conditions) and high fractions of industrial waste in the feedstock was also observed. The process imbalances and suboptimal conditions are mainly allowed to occur due to 1) inadequate knowledge about the waste composition, 2) inadequate knowledge about the waste degradation characteristics, 3) inadequate...... of ammonia or long chain fatty acids is in most cases expected to be the cause of microbial inhibitions/imbalances while foaming in the prestorage tanks and digesters is the most important practical process problem at the plants. A correlation between increased residual biogas production (suboptimal process...

  6. An Analysis of Economic Growth, Competitiveness and Macroeconomic Imbalances in the European Union

    Directory of Open Access Journals (Sweden)

    Gheorghe Hurduzeu

    2015-09-01

    Full Text Available Taking into consideration the determinants of the economic crisis and of the sovereign debt crisis, we aim to analyze the dynamics of the European economies and discuss changes related to macroeconomic imbalances, as highlighted by the recent crises as an important factor of the unfavorable dynamics registered during the last years. In this respect we considered both internal and external imbalances, as specified in the macroeconomic imbalance procedure that was implemented for the European Union member states since 2012, as a response to the crises that affected all open economies of the world. The purpose of this article is to provide a comprehensive analysis of economic imbalances in the European Union and to determine their influence on economic growth.

  7. SYSTEMIC IMBALANCE OF ESSENTIAL METALS AND CARDIAC GENE EXPRESSION IN RATS FOLLOWING ACUTE PULMONARY ZINC EXPOSURE

    Science.gov (United States)

    We have recently demonstrated that PM containing water-soluble zinc may cause cardiac injury following pulmonary exposure. To investigate if pulmonary zinc exposure causes systemic metal imbalance and direct cardiac effects, we intratracheally (IT) instilled male Wistar Kyoto (WK...

  8. Consensus-based Distributed Control for Accurate Reactive, Harmonic and Imbalance Power Sharing in Microgrids

    DEFF Research Database (Denmark)

    Zhou, Jianguo; Kim, Sunghyok; Zhang, Huaguang

    2017-01-01

    quality at the point of common coupling (PCC). Further, a distributed consensus protocol is developed to adaptively regulate the virtual impedance at fundamental frequency and selected harmonic frequencies. Additionally, a dynamic consensus based method is adopted to restore the voltage to their average......This paper investigates the issue of accurate reactive, harmonic and imbalance power sharing in a microgrid. Harmonic and imbalance droop controllers are developed to proportionally share the harmonic power and the imbalance power among distributed generation (DG) units and improve the voltage...... voltage. With the proposed methods, the microgrid system reliability and flexibility can be enhanced and the knowledge of the line impedance is not required. And the reactive, harmonic and imbalance power can be proportionally shared among the DG units. Moreover, the quality of the voltage at PCC can...

  9. Are foreign investments in land leading to an imbalance in the hydrological cycle?

    Science.gov (United States)

    Steenhuis, T. S.; Theodore, C.; Makki, F. M.

    2012-12-01

    Over the past few years, large-scale acquisitions of farmland have taken place across the world. Although the land acquisitions are generally portrayed as a land grab in Africa, in almost all cases it is the extra water that is consumed by the crops that brings a new imbalance in the hydrological science. Understanding the imbalance is central to livelihoods and food security of the people downstream because almost all rivers in Africa with the exception of the Congo are being fully consumed before they enter the ocean. In this talk we will show what the effects on the water imbalance caused by foreign and national investments in the Blue Nile basin in the Ethiopian highlands has on the water availability in the downstream countries and whether the imbalance can be made up by increasing irrigation efficiency.

  10. Analysis and compensation of I/Q imbalance in amplify-and-forward cooperative systems

    KAUST Repository

    Qi, Jian

    2012-04-01

    In this paper, dual-hop amplify-and-forward (AF) cooperative systems in the presence of in-phase and quadrature-phase (I/Q) imbalance, which refers to the mismatch between components in I and Q branches, are investigated. First, we analyze the performance of the considered AF cooperative protocol without compensation for I/Q imbalance as the benchmark. Furthermore, a compensation algorithm for I/Q imbalance is proposed, which makes use of the received signals at the destination, from the source and relay nodes, together with their conjugations to detect the transmitted signal. The performance of the AF cooperative system under study is evaluated in terms of average symbol error probability (SEP), which is derived considering transmission over Rayleigh fading channels. Numerical results are provided and show that the proposed compensation algorithm can efficiently mitigate the effect of I/Q imbalance. © 2012 IEEE.

  11. Cenozoic carbon cycle imbalances and a variable weathering feedback

    Science.gov (United States)

    Caves, Jeremy K.; Jost, Adam B.; Lau, Kimberly V.; Maher, Kate

    2016-09-01

    The long-term stability of Earth's climate and the recovery of the ocean-atmosphere system after carbon cycle perturbations are often attributed to a stabilizing negative feedback between silicate weathering and climate. However, evidence for the operation of this feedback over million-year timescales and in response to tectonic and long-term climatic change remains scarce. For example, the past 50 million years of the Cenozoic Era are characterized by long-term cooling and declining atmospheric CO2 (pCO2). During this interval, constant or decreasing carbon fluxes from the solid Earth to the atmosphere suggest that stable or decreasing weathering fluxes are needed to balance the carbon cycle. In contrast, marine isotopic proxies of weathering (i.e., 87Sr/86Sr, δ7 Li , and 187Os/188Os) are interpreted to reflect increasing weathering fluxes. Here, we evaluate the existence of a negative feedback by reconstructing the imbalance in the carbon cycle during the Cenozoic using the surface inventories of carbon and alkalinity. Only a sustained 0.25-0.5% increase in silicate weathering is necessary to explain the long-term decline in pCO2 over the Cenozoic. We propose that the long-term decrease in pCO2 is due to an increase in the strength of the silicate weathering feedback (i.e., the constant of proportionality between the silicate weathering flux and climate), rather than an increase in the weathering flux. This increase in the feedback strength, which mirrors the marine isotope proxies, occurs as transient, 1 million year timescales remains invariant to match the long-term inputs of carbon. Over the Cenozoic, this results in stable long-term weathering fluxes even as pCO2 decreases. We attribute increasing feedback strength to a change in the type and reactivity of rock in the weathering zone, which collectively has increased the reactivity of the surface of the Earth. Increasing feedback strength through the Cenozoic reconciles mass balance in the carbon cycle with

  12. Drug-target interaction prediction via class imbalance-aware ensemble learning.

    Science.gov (United States)

    Ezzat, Ali; Wu, Min; Li, Xiao-Li; Kwoh, Chee-Keong

    2016-12-22

    Multiple computational methods for predicting drug-target interactions have been developed to facilitate the drug discovery process. These methods use available data on known drug-target interactions to train classifiers with the purpose of predicting new undiscovered interactions. However, a key challenge regarding this data that has not yet been addressed by these methods, namely class imbalance, is potentially degrading the prediction performance. Class imbalance can be divided into two sub-problems. Firstly, the number of known interacting drug-target pairs is much smaller than that of non-interacting drug-target pairs. This imbalance ratio between interacting and non-interacting drug-target pairs is referred to as the between-class imbalance. Between-class imbalance degrades prediction performance due to the bias in prediction results towards the majority class (i.e. the non-interacting pairs), leading to more prediction errors in the minority class (i.e. the interacting pairs). Secondly, there are multiple types of drug-target interactions in the data with some types having relatively fewer members (or are less represented) than others. This variation in representation of the different interaction types leads to another kind of imbalance referred to as the within-class imbalance. In within-class imbalance, prediction results are biased towards the better represented interaction types, leading to more prediction errors in the less represented interaction types. We propose an ensemble learning method that incorporates techniques to address the issues of between-class imbalance and within-class imbalance. Experiments show that the proposed method improves results over 4 state-of-the-art methods. In addition, we simulated cases for new drugs and targets to see how our method would perform in predicting their interactions. New drugs and targets are those for which no prior interactions are known. Our method displayed satisfactory prediction performance and was

  13. Compensatory regulation of acid-base balance during salinity transfer in rainbow trout (Oncorhynchus mykiss).

    Science.gov (United States)

    Gilmour, K M; Perry, S F; Esbaugh, A J; Genz, J; Taylor, J R; Grosell, M

    2012-02-01

    In seawater-acclimated rainbow trout (Oncorhynchus mykiss), base secretion into the intestine is a key component of the intestinal water absorption that offsets osmotic water loss to the marine environment. Acid-base balance is maintained by the matched excretion of acid equivalents via other routes, presumably the gill and/or kidney. The goal of the present study was to examine acid-base balance in rainbow trout upon transfer to more dilute environments, conditions under which base excretion into the intestine is predicted to fall, requiring compensatory adjustments of acid excretion at the gill and/or kidney if acid-base balance is to be maintained. Net acid excretion via the gill/kidney and rectal fluid, and blood acid-base status were monitored in seawater-acclimated rainbow trout maintained in seawater or transferred to iso-osmotic conditions. As predicted, transfer to iso-osmotic conditions significantly reduced base excretion into the rectal fluid (by ~48%). Transfer to iso-osmotic conditions also significantly reduced the excretion of titratable acidity via extra-intestinal routes from 183.4 ± 71.3 to -217.5 ± 42.7 μmol kg(-1) h(-1) (N = 7). At the same time, however, ammonia excretion increased significantly during iso-osmotic transfer (by ~72%) so that the apparent overall reduction in net acid excretion (from 419.7 ± 92.9 to 189.2 ± 76.5 μmol kg(-1 )h(-1); N = 7) was not significant. Trout maintained blood acid-base status during iso-osmotic transfer, although arterial pH was significantly higher in transferred fish than in those maintained in seawater. To explore the mechanisms underlying these adjustments of acid-base regulation, the relative mRNA expression and where possible, activity of a suite of proteins involved in acid-base balance were examined in intestine, gill and kidney. At the kidney, reduced mRNA expression of carbonic anhydrase (CA; cytosolic and membrane-associated CA IV), V-type H(+)-ATPase, and Na(+)/HCO(3) (-) co

  14. Widely Linear Blind Adaptive Equalization for Transmitter IQ-Imbalance/Skew Compensation in Multicarrier Systems

    DEFF Research Database (Denmark)

    Porto da Silva, Edson; Zibar, Darko

    2016-01-01

    Simple analytical widely linear complex-valued models for IQ-imbalance and IQ-skew effects in multicarrier transmitters are presented. To compensate for such effects, a 4×4 MIMO widely linear adaptive equalizer is proposed and experimentally validated.......Simple analytical widely linear complex-valued models for IQ-imbalance and IQ-skew effects in multicarrier transmitters are presented. To compensate for such effects, a 4×4 MIMO widely linear adaptive equalizer is proposed and experimentally validated....

  15. General characteristics of patients with electrolyte imbalance admitted to emergency department

    OpenAIRE

    Balcı, Arif Kadri; Koksal, Ozlem; Kose, Ataman; Armagan, Erol; Ozdemir, Fatma; Inal, Taylan; Oner, Nuran

    2013-01-01

    BACKGROUND: Fluid and electrolyte balance is a key concept to understand for maintaining homeostasis, and for a successful treatment of many metabolic disorders. There are various regulating mechanisms for the equilibrium of electrolytes in organisms. Disorders of these mechanisms result in electrolyte imbalances that may be life-threatening clinical conditions. In this study we defined the electrolyte imbalance characteristics of patients admitted to our emergency department. METHODS: This s...

  16. Drug-target interaction prediction via class imbalance-aware ensemble learning

    OpenAIRE

    Ezzat, Ali; Wu, Min; Li, Xiao-Li; Kwoh, Chee-Keong

    2016-01-01

    Background Multiple computational methods for predicting drug-target interactions have been developed to facilitate the drug discovery process. These methods use available data on known drug-target interactions to train classifiers with the purpose of predicting new undiscovered interactions. However, a key challenge regarding this data that has not yet been addressed by these methods, namely class imbalance, is potentially degrading the prediction performance. Class imbalance can be divided ...

  17. Employment and the “Investment Gap”: An Econometric Model of European Imbalances

    OpenAIRE

    Campiglio, Luigi Pierfranco

    2015-01-01

    We specify a VEC model based on six main macroeconomic imbalances to explain the Great European Recession, in Germany, France, Spain and Italy, from 1999 to 2013, estimating their long-term relationships. We focus on employment and unemployment as the main imbalances and identify consumption and investment slumps, prompted by fiscal consolidation, as the causes and current account rebalance and low inflation as the main consequences. Our main results are the following: a) public investment is...

  18. Examination of Potential Benefits of an Energy Imbalance Market in the Western Interconnection

    Energy Technology Data Exchange (ETDEWEB)

    Milligan, M.; Clark, K.; King, J.; Kirby, B.; Guo, T.; Liu, G.

    2013-03-01

    In the Western Interconnection, there is significant interest in improving approaches to wide-area coordinated operations of the bulk electric power system, in part because of the increasing penetration of variable generation. One proposed solution is an energy imbalance market. This study focused on that approach alone, with the goal of identifying the potential benefits of an energy imbalance market in the year 2020.

  19. Comprehensive Investigation on Current Imbalance among Parallel Chips inside MW-Scale IGBT Power Modules

    DEFF Research Database (Denmark)

    Wu, Rui; Smirnova, Liudmila; Wang, Huai

    2015-01-01

    With the demands for increasing the power rating and improving reliability level of the high power IGBT modules, there are further needs of understanding how to achieve stable paralleling and identical current sharing between the chips. This paper investigates the stray parameters imbalance among...... parallel chips inside the 1.7 kV/1 kA high power IGBT modules at different frequencies by Ansys Q3D parastics extractor. The resulted current imbalance is further confirmed by experimental measurement....

  20. Recent advances in understanding trans-epithelial acid-base regulation and excretion mechanisms in cephalopods.

    Science.gov (United States)

    Hu, Marian Y; Hwang, Pung-Pung; Tseng, Yung-Che

    2015-01-01

    Cephalopods have evolved complex sensory systems and an active lifestyle to compete with fish for similar resources in the marine environment. Their highly active lifestyle and their extensive protein metabolism has led to substantial acid-base regulatory abilities enabling these organisms to cope with CO2 induced acid-base disturbances. In convergence to teleost, cephalopods possess an ontogeny-dependent shift in ion-regulatory epithelia with epidermal ionocytes being the major site of embryonic acid-base regulation and ammonia excretion, while gill epithelia take these functions in adults. Although the basic morphology and excretory function of gill epithelia in cephalopods were outlined almost half a century ago, modern immunohistological and molecular techniques are bringing new insights to the mechanistic basis of acid-base regulation and excretion of nitrogenous waste products (e.g. NH3/NH4 (+)) across ion regulatory epithelia of cephalopods. Using cephalopods as an invertebrate model, recent findings reveal partly conserved mechanisms but also novel aspects of acid-base regulation and nitrogen excretion in these exclusively marine animals. Comparative studies using a range of marine invertebrates will create a novel and exciting research direction addressing the evolution of pH regulatory and excretory systems.

  1. Complexity in Acid-Base Titrations: Multimer Formation Between Phosphoric Acids and Imines.

    Science.gov (United States)

    Malm, Christian; Kim, Heejae; Wagner, Manfred; Hunger, Johannes

    2017-08-10

    Solutions of Brønsted acids with bases in aprotic solvents are not only common model systems to study the fundamentals of proton transfer pathways but are also highly relevant to Brønsted acid catalysis. Despite their importance the light nature of the proton makes characterization of acid-base aggregates challenging. Here, we track such acid-base interactions over a broad range of relative compositions between diphenyl phosphoric acid and the base quinaldine in dichloromethane, by using a combination of dielectric relaxation and NMR spectroscopy. In contrast to what one would expect for an acid-base titration, we find strong deviations from quantitative proton transfer from the acid to the base. Even for an excess of the base, multimers consisting of one base and at least two acid molecules are formed, in addition to the occurrence of proton transfer from the acid to the base and simultaneous formation of ion pairs. For equimolar mixtures such multimers constitute about one third of all intermolecular aggregates. Quantitative analysis of our results shows that the acid-base association constant is only around six times larger than that for the acid binding to an acid-base dimer, that is, to an already protonated base. Our findings have implications for the interpretation of previous studies of reactive intermediates in organocatalysis and provide a rationale for previously observed nonlinear effects in phosphoric acid catalysis. © 2017 The Authors. Published by Wiley-VCH Verlag GmbH & Co. KGaA.

  2. Electrolyte and Acid-Base Disturbances in End-Stage Liver Disease: A Physiopathological Approach.

    Science.gov (United States)

    Jiménez, José Víctor; Carrillo-Pérez, Diego Luis; Rosado-Canto, Rodrigo; García-Juárez, Ignacio; Torre, Aldo; Kershenobich, David; Carrillo-Maravilla, Eduardo

    2017-08-01

    Electrolyte and acid-base disturbances are frequent in patients with end-stage liver disease; the underlying physiopathological mechanisms are often complex and represent a diagnostic and therapeutic challenge to the physician. Usually, these disorders do not develop in compensated cirrhotic patients, but with the onset of the classic complications of cirrhosis such as ascites, renal failure, spontaneous bacterial peritonitis and variceal bleeding, multiple electrolyte, and acid-base disturbances emerge. Hyponatremia parallels ascites formation and is a well-known trigger of hepatic encephalopathy; its management in this particular population poses a risky challenge due to the high susceptibility of cirrhotic patients to osmotic demyelination. Hypokalemia is common in the setting of cirrhosis: multiple potassium wasting mechanisms both inherent to the disease and resulting from its management make these patients particularly susceptible to potassium depletion even in the setting of normokalemia. Acid-base disturbances range from classical respiratory alkalosis to high anion gap metabolic acidosis, almost comprising the full acid-base spectrum. Because most electrolyte and acid-base disturbances are managed in terms of their underlying trigger factors, a systematic physiopathological approach to their diagnosis and treatment is required.

  3. Allostatic Load and Effort-Reward Imbalance: Associations over the Working-Career

    Directory of Open Access Journals (Sweden)

    José Ignacio Cuitún Coronado

    2018-01-01

    Full Text Available Although associations between work stressors and stress-related biomarkers have been reported in cross-sectional studies, the use of single time measurements of work stressors could be one of the reasons for inconsistent associations. This study examines whether repeated reports of work stress towards the end of the working career predicts allostatic load, a measure of chronic stress related physiological processes. Data from waves 2 to 6 of the English Longitudinal Study of Ageing (ELSA were analysed, with a main analytical sample of 2663 older adults (aged 50+ who had at least one measurement of effort-reward imbalance between waves 2–6 and a measurement of allostatic load at wave 6. Cumulative work stress over waves 2–6 were measured by the effort-reward imbalance model. ELSA respondents who had reported two or more occasions of imbalance had a higher (0.3 estimate of the allostatic load index than those who did not report any imbalance, controlling for a range of health and socio-demographic factors, as well as allostatic load at baseline. More recent reports of imbalance were significantly associated with a higher allostatic load index, whereas reports of imbalance from earlier waves of ELSA were not. The accumulation of work related stressors could have adverse effects on chronic stress biological processes.

  4. Investigation of Psychological Health and Migraine Headaches Among Personnel According to Effort-Reward Imbalance Model

    Directory of Open Access Journals (Sweden)

    Z. Darami

    2012-05-01

    Full Text Available Background and aims: The relationship between physical-mental health and Migraine headaches and stress, especially job stress, is known. Many factors can construct job stress in work settings. The factor that has gained much attention recently is inequality (imbalance of employees’ effort versus the reward they gain. The aim of the current attempt was to investigate the validity of effort-reward imbalance model and indicate the relation of this model with migraine headaches and psychological well-being among subjects in balance and imbalance groups. Methods: Participants were 180 personnel of Oil distribution company located in Isfahan city, and instruments used were General health questionnaire (Goldberg & Hilier, Social Re-adjustment Rating Scale (Holmes & Rahe, Ahvaz Migraine Questionnaire (Najariyan and Effort-reward imbalance scale (Van Vegchel & et al.   Results: The result of exploratory and confirmatory factor analysis for investigating the Construct validity of the effort-reward imbalance model showed that in both analyses, the two factor model was confirmed. Moreover, findings indicate that balance group was in better psychological (p<0/01 and physical (migraine (p<0/05 status comparing to the imbalance group. These findings indicate the significance of justice to present appropriate reward relative to personnel performance on their health.   Conclusion: Implication of these findings can improve Iranian industrial personnel health from both physical and psychological aspects.  

  5. Effects of specific muscle imbalance improvement training on the balance ability in elite fencers.

    Science.gov (United States)

    Kim, Taewhan; Kil, Sekee; Chung, Jinwook; Moon, Jeheon; Oh, Eunyoung

    2015-05-01

    [Purpose] The lunge Motion that occurs frequently in fencing training and matches results in imbalance of the upper and lower limbs muscles. This research focuses on the improvement of the imbalance that occurs in the national team fencers of the Republic of Korea through specific muscle imbalance improvement training. [Subjects] The subjects of this research were limited to right-handed male fencers. Nine male, right-handed national fencing athletes were selected for this study (4 epee, 5 sabre; age 28.2 ± 2.2 years; height 182.3 ± 4.0 cm; weight 76.5 ± 8.2 kg; experience 12.4 ± 3.0 years). [Methods] The specific muscle imbalance improvement training program was performed for 12 weeks and Pre-Post tests were to evaluate its effect on the experimental group. Measurements comprised anthropometry, test of balance, and movement analysis. [Results] After the training program, mediolateral sway of the nondominant lower limb and the balance scale showed statistically significant improvement. [Conclusion] The specific muscle imbalance improvement training program used in this research was proven to be effective for improving the muscle imbalance of elite fencers.

  6. Erasure and reestablishment of random allelic expression imbalance after epigenetic reprogramming.

    Science.gov (United States)

    Jeffries, Aaron Richard; Uwanogho, Dafe Aghogho; Cocks, Graham; Perfect, Leo William; Dempster, Emma; Mill, Jonathan; Price, Jack

    2016-10-01

    Clonal level random allelic expression imbalance and random monoallelic expression provides cellular heterogeneity within tissues by modulating allelic dosage. Although such expression patterns have been observed in multiple cell types, little is known about when in development these stochastic allelic choices are made. We examine allelic expression patterns in human neural progenitor cells before and after epigenetic reprogramming to induced pluripotency, observing that loci previously characterized by random allelic expression imbalance (0.63% of expressed genes) are generally reset to a biallelic state in induced pluripotent stem cells (iPSCs). We subsequently neuralized the iPSCs and profiled isolated clonal neural stem cells, observing that significant random allelic expression imbalance is reestablished at 0.65% of expressed genes, including novel loci not found to show allelic expression imbalance in the original parental neural progenitor cells. Allelic expression imbalance was associated with altered DNA methylation across promoter regulatory regions, with clones characterized by skewed allelic expression being hypermethylated compared to their biallelic sister clones. Our results suggest that random allelic expression imbalance is established during lineage commitment and is associated with increased DNA methylation at the gene promoter. © 2016 Jeffries et al.; Published by Cold Spring Harbor Laboratory Press for the RNA Society.

  7. Effect of acute acid loading on acid-base and calcium metabolism

    DEFF Research Database (Denmark)

    Osther, Palle J

    2006-01-01

    OBJECTIVE: To investigate the acid-base and calcium metabolic responses to acute non-carbonic acid loading in idiopathic calcium stone-formers and healthy males using a quantitative organ physiological approach. MATERIAL AND METHODS: Five-h ammonium chloride loading studies were performed in 12...... male recurrent idiopathic calcium stone-formers and 12 matched healthy men using a randomized, placebo-controlled, cross-over design. Arterialized capillary blood, serum and urine were collected hourly for measurement of electrolytes, ionized calcium, magnesium, phosphate, parathyroid hormone and acid-base...... status. Concentrations of non-metabolizable base (NB) and acid (NA) were calculated from measured concentrations of non-metabolizable ions. RESULTS: The extracellular acid-base status in the stone-formers during basal conditions and acid loading was comparable to the levels in the healthy controls...

  8. Acid-base regulation in tadpoles of Rana catesbeiana exposed to environmental hypercapnia

    DEFF Research Database (Denmark)

    Busk, Morten; Larsen, Erik Hviid; Jensen, Frank B.

    1997-01-01

    Tadpoles of Rana catesbeiana were exposed to different levels of environmental hypercapnia. The acid-base regulatory response differed from that in adult amphibians in showing a high degree of pH compensation in the extracellular fluid (65-85%) and complete compensation in the intracellular fluid......). It is suggested that the large bicarbonate efflux from the animal is a consequence of the dissolution of CaCO3 stores and the delayed adjustment of bicarbonate-retaining mechanisms. Re-exposure of tadpoles to hypercapnia after 1-3 weeks of normocapnic recovery only affected transepithelial fluxes of acid-base...

  9. [Disorders of the acid-base balance and the anion gap].

    Science.gov (United States)

    Kimmel, Martin; Alscher, Mark Dominik

    2016-10-01

    The regulation of the acid-base balance and pH is critical for the organism. The most important buffer system is CO2 / HCO3(-). The kidney controls systemic bicarbonate and therefore the metabolic regulation and the lung is relevant for respiratory regulation by an effective CO2 elimination. There are four acid-base disorders with two metabolic and two respiratory disorders (acidosis and alkalosis). The anion gap enables a further workup of metabolic acidosis. © Georg Thieme Verlag KG Stuttgart · New York.

  10. The third annual BRDS on research and development of nucleic acid-based nanomedicines.

    Science.gov (United States)

    Chaudhary, Amit Kumar; Mahato, Ram I

    2017-02-01

    The completion of human genome project, decrease in the sequencing cost, and correlation of genome sequencing data with specific diseases led to the exponential rise in the nucleic acid-based therapeutic approaches. In the third annual Biopharmaceutical Research and Development Symposium (BRDS) held at the Center for Drug Discovery and Lozier Center for Pharmacy Sciences and Education at the University of Nebraska Medical Center (UNMC), we highlighted the remarkable features of the nucleic acid-based nanomedicines, their significance, NIH funding opportunities on nanomedicines and gene therapy research, challenges and opportunities in the clinical translation of nucleic acids into therapeutics, and the role of intellectual property (IP) in drug discovery and development.

  11. Intrinsic MYH7 expression regulation contributes to tissue level allelic imbalance in hypertrophic cardiomyopathy.

    Science.gov (United States)

    Montag, Judith; Syring, Mandy; Rose, Julia; Weber, Anna-Lena; Ernstberger, Pia; Mayer, Anne-Kathrin; Becker, Edgar; Keyser, Britta; Dos Remedios, Cristobal; Perrot, Andreas; van der Velden, Jolanda; Francino, Antonio; Navarro-Lopez, Francesco; Ho, Carolyn Yung; Brenner, Bernhard; Kraft, Theresia

    2017-11-03

    HCM, the most common inherited cardiac disease, is mainly caused by mutations in sarcomeric genes. More than a third of the patients are heterozygous for mutations in the MYH7 gene encoding for the β-myosin heavy chain. In HCM-patients, expression of the mutant and the wildtype allele can be unequal, thus leading to fractions of mutant and wildtype mRNA and protein which deviate from 1:1. This so-called allelic imbalance was detected in whole tissue samples but also in individual cells. There is evidence that the severity of HCM not only depends on the functional effect of the mutation itself, but also on the fraction of mutant protein in the myocardial tissue. Allelic imbalance has been shown to occur in a broad range of genes. Therefore, we aimed to examine whether the MYH7-alleles are intrinsically expressed imbalanced or whether the allelic imbalance is solely associated with the disease. We compared the expression of MYH7-alleles in non-HCM donors and in HCM-patients with different MYH7-missense mutations. In the HCM-patients, we identified imbalanced as well as equal expression of both alleles. Also at the protein level, allelic imbalance was determined. Most interestingly, we also discovered allelic imbalance and balance in non-HCM donors. Our findings therefore strongly indicate that apart from mutation-specific mechanisms, also non-HCM associated allelic-mRNA expression regulation may account for the allelic imbalance of the MYH7 gene in HCM-patients. Since the relative amount of mutant mRNA and protein or the extent of allelic imbalance has been associated with the severity of HCM, individual analysis of the MYH7-allelic expression may provide valuable information for the prognosis of each patient.

  12. Effect of effort-reward imbalance and burnout on infection control among Ecuadorian nurses.

    Science.gov (United States)

    Colindres, C V; Bryce, E; Coral-Rosero, P; Ramos-Soto, R M; Bonilla, F; Yassi, A

    2017-11-07

    Nurses are frequently exposed to transmissible infections, yet adherence to infection control measures is suboptimal. There has been inadequate research into how the psychosocial work environment affects compliance with infection control measures, especially in low- and middle-income countries. To examine the association between effort-reward imbalance, burnout and adherence to infection control measures among nurses in Ecuador. A cross-sectional study linking psychosocial work environment indicators to infection control adherence. The study was conducted among 333 nurses in four Ecuadorian hospitals. Self-administered questionnaires assessed demographic variables, perceived infection risk, effort-reward imbalance, burnout and infection control adherence. Increased effort-reward imbalance was found to be a unique incremental predictor of exposure to burnout, and burnout was a negative unique incremental predictor of nurses' self-reported adherence with infection control measures. Results suggest an effort-reward imbalance-burnout continuum, which, at higher levels, contributes to reduce adherence to infection control. The Ecuadorean government has made large efforts to improve universal access to health care, yet this study suggests that workplace demands on nurses remain problematic. This study highlights the contribution of effort-reward-imbalance-burnout continuum to the chain of infection by decreased adherence to infection control of nurses. Health authorities should closely monitor the effect of new policies on psychosocial work environment, especially when expanding services and increasing public accessibility with limited resources. Additionally, organizational and psychosocial interventions targeting effort-reward imbalance and burnout in nurses should be considered part of a complete infection prevention and control strategy. Further study is warranted to identify interventions that best ameliorate effort-reward imbalance and burnout in low- and middle

  13. Intracellular pH regulation by acid-base transporters in mammalian neurons.

    Science.gov (United States)

    Ruffin, Vernon A; Salameh, Ahlam I; Boron, Walter F; Parker, Mark D

    2014-01-01

    Intracellular pH (pHi) regulation in the brain is important in both physiological and physiopathological conditions because changes in pHi generally result in altered neuronal excitability. In this review, we will cover 4 major areas: (1) The effect of pHi on cellular processes in the brain, including channel activity and neuronal excitability. (2) pHi homeostasis and how it is determined by the balance between rates of acid loading (J L) and extrusion (J E). The balance between J E and J L determine steady-state pHi, as well as the ability of the cell to defend pHi in the face of extracellular acid-base disturbances (e.g., metabolic acidosis). (3) The properties and importance of members of the SLC4 and SLC9 families of acid-base transporters expressed in the brain that contribute to J L (namely the Cl-HCO3 exchanger AE3) and J E (the Na-H exchangers NHE1, NHE3, and NHE5 as well as the Na(+)- coupled HCO3 (-) transporters NBCe1, NBCn1, NDCBE, and NBCn2). (4) The effect of acid-base disturbances on neuronal function and the roles of acid-base transporters in defending neuronal pHi under physiopathologic conditions.

  14. Intracellular pH regulation by acid/base transporters in mammalian neurons

    Directory of Open Access Journals (Sweden)

    Vernon A. Ruffin

    2014-02-01

    Full Text Available Intracellular pH (pHi regulation in the brain is important in both physiological and physiopathological conditions because changes in pHi generally result in altered neuronal excitability. In this review, we will cover 4 major areas: [1] The effect of pHi on cellular processes in the brain, including channel activity and neuronal excitability. [2] pHi homeostasis and how it is determined by the balance between rates of acid loading (JL and extrusion (JE. The balance between JE and JL determine steady-state pHi, as well as the ability of the cell to defend pHi in the face of extracellular acid-base disturbances (e.g. metabolic acidosis. [3] The properties and importance of members of the SLC4 and SLC9 families of acid-base transporters expressed in the brain that contribute to JL (namely the Cl-HCO3 exchanger AE3 and JE (the Na-H exchangers NHE1, NHE3 and NHE5 as well as the Na+- coupled HCO3- transporters NBCe1, NBCn1, NDCBE, and NBCn2. [4] The effect of acid-base disturbances on neuronal function and the roles of acid-base transporters in defending neuronal pHi under physiopathologic conditions.

  15. Amino acid based phosphoramidite ligands for the rhodium-catalyzed asymmetric hydrogenation

    NARCIS (Netherlands)

    Breuil, P.A.R.; Reek, J.N.H.

    2009-01-01

    Two sets of amino acid based phosphoramidite ligands with either a BINOL backbone (S-b-1a-e and Rb-1a) or a flexible biphenol backbone (2a-c and 2f) were synthesized and evaluated in the rhodium-catalyzed hydrogenation of different functionalized alkenes: dimethyl itaconate (3), methyl

  16. Effect of benzoic acid supplementation on acid-base status and mineralmetabolism in catheterized growing pigs

    DEFF Research Database (Denmark)

    Nørgaard, Jan Værum; Fernández, José Adalberto; Sørensen, Kristina Ulrich

    2010-01-01

    Benzoic acid (BA) in diets for growing pigs results in urinary acidification and reduced ammonia emission. The objective was to study the impact of BA supplementation on the acid-base status and mineral metabolism in pigs. Eight female 50-kg pigs, fitted with a catheter in the abdominal aorta, were...

  17. A small-angle neutron scattering study of cholic acid-based organogel systems

    NARCIS (Netherlands)

    Willemen, H.M.; Marcelis, A.T.M.; Sudhölter, E.J.R.; Bouwman, W.G.; Deme, B.; Terech, P.

    2004-01-01

    Small-angle neutron scattering measurements were performed on some cholic acid-based gel systems in order to gain detailed information about the network structure. The presence of thin fibers with a radius of about 10-20 Å was found for various gelators. Two types of interaction between different

  18. The incidence of electrolyte and acid-base abnormalities in critically ...

    African Journals Online (AJOL)

    Background: Electrolytes and acid-base disorders are common challenges seen in the intensive care unit (ICU) resulting in difficulty in weaning patients off the ventilator, prolonged admission periods, preventable cardiac arrhythmias and cardiac arrest. These require prompt lab results most of which are done serially, ...

  19. Isoelectric Point, Electric Charge, and Nomenclature of the Acid-Base Residues of Proteins

    Science.gov (United States)

    Maldonado, Andres A.; Ribeiro, Joao M.; Sillero, Antonio

    2010-01-01

    The main object of this work is to present the pedagogical usefulness of the theoretical methods, developed in this laboratory, for the determination of the isoelectric point (pI) and the net electric charge of proteins together with some comments on the naming of the acid-base residues of proteins. (Contains 8 figures and 4 tables.)

  20. Interactive Computer-Assisted Instruction in Acid-Base Physiology for Mobile Computer Platforms

    Science.gov (United States)

    Longmuir, Kenneth J.

    2014-01-01

    In this project, the traditional lecture hall presentation of acid-base physiology in the first-year medical school curriculum was replaced by interactive, computer-assisted instruction designed primarily for the iPad and other mobile computer platforms. Three learning modules were developed, each with ~20 screens of information, on the subjects…

  1. Nutrient intake, acid base status and weight gain in water buffalo ...

    African Journals Online (AJOL)

    The impact of different dietary levels of sodium bicarbonate (NaHCO3) on nutrient intake, acid-base status, nitrogen balance and weight gain was examined in growing male buffalo (Bubalus bubalis) calves exposed to hot summer conditions. In a complete randomized block design 60 animals of similar age and weight ...

  2. Acid-base indicator properties of dyes from local plants I: Dyes from ...

    African Journals Online (AJOL)

    DR. MIKE HORSFALL

    ABSTRACT: The acid-base indicator properties of aqueous and ethanol extracts from calyces of H. sabdariffa (Zobo) and a dye obtained from the ripe fruits of Basella alba (Indian spinach), two local plants, were investigated. A purple coloured dye obtained from the ripe fruits of Basella alba showed a λmax at. 580nm ...

  3. Nutrient intake, acid base status and weight gain in water buffalo ...

    African Journals Online (AJOL)

    p2492989

    Abstract. The impact of different dietary levels of sodium bicarbonate (NaHCO3) on nutrient intake, acid-base status, nitrogen balance and weight gain was examined in growing male buffalo (Bubalus bubalis) calves exposed to hot summer conditions. In a complete randomized block design 60 animals of similar age and.

  4. Maternal and Fetal Acid-Base Chemistry: A Major Determinant of ...

    African Journals Online (AJOL)

    Very small changes in pH may significantly affect the function of various fetal organ systems, such as the central nervous system, and the cardiovascular system with associated fetal distress and poor Apgar score. Review of existing data on maternal-fetal acid-base balance in pregnancy highlight the factors that are ...

  5. Lewis Acid-Base Properties of a Low Carbon Aluminium Killed Steel ...

    African Journals Online (AJOL)

    An important factor in achieving maximum adhesion of a particular coating system to the substrate lies in the proper preparation of the substrate prior to the application of paint. The Lewis acid-base properties of the outer metal surface play a determinant role in many of these applications, and the chemical reactions involved ...

  6. The Acid-Base Titration of a Very Weak Acid: Boric Acid

    Science.gov (United States)

    Celeste, M.; Azevedo, C.; Cavaleiro, Ana M. V.

    2012-01-01

    A laboratory experiment based on the titration of boric acid with strong base in the presence of d-mannitol is described. Boric acid is a very weak acid and direct titration with NaOH is not possible. An auxiliary reagent that contributes to the release of protons in a known stoichiometry facilitates the acid-base titration. Students obtain the…

  7. Students' Understanding of Acid, Base and Salt Reactions in Qualitative Analysis.

    Science.gov (United States)

    Tan, Kim-Chwee Daniel; Goh, Ngoh-Khang; Chia, Lian-Sai; Treagust, David F.

    2003-01-01

    Uses a two-tier, multiple-choice diagnostic instrument to determine (n=915) grade 10 students' understanding of the acid, base, and salt reactions involved in basic qualitative analysis. Reports that many students did not understand the formation of precipitates and the complex salts, acid/salt-base reactions, and thermal decomposition involved in…

  8. Acid-Base Chemistry According to Robert Boyle: Chemical Reactions in Words as well as Symbols

    Science.gov (United States)

    Goodney, David E.

    2006-01-01

    Examples of acid-base reactions from Robert Boyle's "The Sceptical Chemist" are used to illustrate the rich information content of chemical equations. Boyle required lengthy passages of florid language to describe the same reaction that can be done quite simply with a chemical equation. Reading or hearing the words, however, enriches the student's…

  9. Intracellular pH regulation by acid-base transporters in mammalian neurons

    Science.gov (United States)

    Ruffin, Vernon A.; Salameh, Ahlam I.; Boron, Walter F.; Parker, Mark D.

    2014-01-01

    Intracellular pH (pHi) regulation in the brain is important in both physiological and physiopathological conditions because changes in pHi generally result in altered neuronal excitability. In this review, we will cover 4 major areas: (1) The effect of pHi on cellular processes in the brain, including channel activity and neuronal excitability. (2) pHi homeostasis and how it is determined by the balance between rates of acid loading (JL) and extrusion (JE). The balance between JE and JL determine steady-state pHi, as well as the ability of the cell to defend pHi in the face of extracellular acid-base disturbances (e.g., metabolic acidosis). (3) The properties and importance of members of the SLC4 and SLC9 families of acid-base transporters expressed in the brain that contribute to JL (namely the Cl-HCO3 exchanger AE3) and JE (the Na-H exchangers NHE1, NHE3, and NHE5 as well as the Na+- coupled HCO3− transporters NBCe1, NBCn1, NDCBE, and NBCn2). (4) The effect of acid-base disturbances on neuronal function and the roles of acid-base transporters in defending neuronal pHi under physiopathologic conditions. PMID:24592239

  10. Changes in acid-base and ion balance during exercise in normoxia and normobaric hypoxia.

    Science.gov (United States)

    Lühker, Olaf; Berger, Marc Moritz; Pohlmann, Alexander; Hotz, Lorenz; Gruhlke, Tilmann; Hochreiter, Marcel

    2017-11-01

    Both exercise and hypoxia cause complex changes in acid-base homeostasis. The aim of the present study was to investigate whether during intense physical exercise in normoxia and hypoxia, the modified physicochemical approach offers a better understanding of the changes in acid-base homeostasis than the traditional Henderson-Hasselbalch approach. In this prospective, randomized, crossover trial, 19 healthy males completed an exercise test until voluntary fatigue on a bicycle ergometer on two different study days, once during normoxia and once during normobaric hypoxia (12% oxygen, equivalent to an altitude of 4500 m). Arterial blood gases were sampled during and after the exercise test and analysed according to the modified physicochemical and Henderson-Hasselbalch approach, respectively. Peak power output decreased from 287 ± 9 Watts in normoxia to 213 ± 6 Watts in hypoxia (-26%, P acid ions) and non-volatile weak acids (i.e. albumin, phosphate ion species) as important contributors. The Henderson-Hasselbalch approach might serve as basis for screening acid-base disturbances, but the modified physicochemical approach offers more detailed insights into the complex changes in acid-base status during exercise in normoxia and hypoxia, respectively.

  11. Effect of Intravenously Administered Crystalloid Solutions on Acid-Base Balance in Domestic Animals.

    Science.gov (United States)

    Muir, W

    2017-09-01

    Intravenous fluid therapy can alter plasma acid-base balance. The Stewart approach to acid-base balance is uniquely suited to identify and quantify the effects of the cationic and anionic constituents of crystalloid solutions on plasma pH. The plasma strong ion difference (SID) and weak acid concentrations are similar to those of the administered fluid, more so at higher administration rates and with larger volumes. A crystalloid's in vivo effects on plasma pH are described by 3 general rules: SID > [HCO3-] increases plasma pH (alkalosis); SID acidity. Appreciation of IV fluid composition and an understanding of basic physicochemical principles provide therapeutically valuable insights about how and why fluid therapy can produce and correct alterations of plasma acid-base equilibrium. The ideal balanced crystalloid should (1) contain species-specific concentrations of key electrolytes (Na(+) , Cl(-) , K(+) , Ca(++) , Mg(++) ), particularly Na(+) and Cl(-) ; (2) maintain or normalize acid-base balance (provide an appropriate SID); and (3) be isosmotic and isotonic (not induce inappropriate fluid shifts) with normal plasma. Copyright © 2017 The Authors. Journal of Veterinary Internal Medicine published by Wiley Periodicals, Inc. on behalf of the American College of Veterinary Internal Medicine.

  12. The Regulation of Acid-Base Balance--A Microprocessor Simulation.

    Science.gov (United States)

    Rasch, Robert W.

    1983-01-01

    Describes a computer program designed to simulate the regulation of acid-base balance, emphasizing regulatory compensations involved in the total process. Includes discussion of equations involved, a sample run of the program, and program listing (MicroSoft Basic). (JN)

  13. The management of acid-base balance in children with diabetic acidosis

    Science.gov (United States)

    Kuzemko, J. A.; Fielding, D. W.; Hudson, F. P.

    1969-01-01

    Acid-base changes in eleven diabetic children admitted to hospital with keto-acidosis are described. Six children required intravenous sodium bicarbonate to correct the metabolic acidosis. It is concluded that immediate use of bicarbonate in these children was efficient, rapid and safe. PMID:4978175

  14. Acid-base titration curves in an integrated computer learning environment

    NARCIS (Netherlands)

    Heck, A.; Kędzierska, E.; Rodgers, L.; Chmurska, M.

    2008-01-01

    The topic of acid-base reactions is a regular component of many chemistry curricula that requires integrated understanding of various areas of introductory chemistry. Many students have considerable difficulties understanding the concepts and processes involved. It has been suggested and confirmed

  15. Effect of acute metabolic acid/base shifts on the human airway calibre.

    NARCIS (Netherlands)

    Brijker, F.; Elshout, F.J.J. van den; Heijdra, Y.F.; Bosch, F.H.; Folgering, H.T.M.

    2001-01-01

    Acute metabolic alkalosis (NaHCO(3)), acidosis (NH(4)Cl), and placebo (NaCl) were induced in 15 healthy volunteers (12 females, median age 34 (range 24-56) years) in a double blind, placebo controlled study to evaluate the presence of the effects on airway calibre. Acid-base shifts were determined

  16. Acid-base and electrolyte disturbances in patients with diabetic ketoacidosis.

    Science.gov (United States)

    Elisaf, M S; Tsatsoulis, A A; Katopodis, K P; Siamopoulos, K C

    1996-09-01

    We undertook the present study to examine the acid-base and electrolyte disturbances in relation to hydration status in patients with diabetic ketoacidosis (DKA). A total of 40 insulin-dependent diabetes mellitus patients (22 male, 18 female), aged 18-61 years with DKA admitted to our hospital during the last 2 years, were studied. The duration of diabetes averaged 9 +/- 2 years. In all cases a detailed investigation of the acid-base status and electrolyte parameters was performed. Twenty-one patients had a pure metabolic acidosis with an increased serum anion gap, seven had DKA combined with hyperchloremic metabolic acidosis, nine had DKA coexisting with metabolic alkalosis, while three had DKA with a concurrent respiratory alkalosis. Hydration status as evidenced by the ratio of urea/creatinine seems to play an important role in the development of mixed acid-base disorders (detected by changes in the ratios delta anion gap/delta bicarbonate (delta AG/delta HCO3) and sodium/chloride (Na/Cl)). In fact, hyperchloremic acidosis developed in the patients with the better hydration status. However, contradictorily, the severely dehydrated patients who experienced recurrent episodes of vomiting developed DKA with a concurrent metabolic alkalosis. Finally, patients with pneumonia or gram-negative septicemia exhibited DKA combined with a primary respiratory alkalosis. We conclude that patients with DKA commonly develop mixed acid-base disorders, which are partly dependent on patients' hydration status.

  17. [The Stewart model. "Modern" approach to the interpretation of the acid-base metabolism].

    Science.gov (United States)

    Rehm, M; Conzen, P F; Peter, K; Finsterer, U

    2004-04-01

    About twenty years ago, Peter Stewart had already published his modern quantitative approach to acid-base chemistry. According to his interpretations, the traditional concepts of the mechanisms behind the changes in acid-base balance are considerably questionable. The main physicochemical principle which must be accomplished in body fluids, is the rule of electroneutrality. There are 3 components in biological fluids which are subject to this principle: a)Water, which is only in minor parts dissociated into H+ and OH-, b)"strong", i.e. completely dissociated, electrolytes, which thus do not interact with other substances, and body substances, such as lactate, and c)"weak", i.e. incompletely dissociated, substances. Peter Stewart strictly distinguished between dependent and independent variables and thus indeed described a new order of acid-base chemistry. The 3 dependent variables (bicarbonate concentration [Bic(-)], pH, and with this also hydrogen ion concentration [H(+)]) can only change if the 3 independent variables allow this change. These 3 independent variables are: 1. Carbon dioxide partial pressure, 2.the total amount of all weak acids ([A-] (Stewart called these ATOT), and 3.strong ion difference (SID). [A(-)] can be calculated from the albumin (Alb) and the phosphate concentration (Pi): [A(-)]=[Alb x (0.123 x pH - 0.631)] + [Pi x (0.309 x pH - 0.469)]. An apparent SID (or "bedside" SID) can be calculated using measurable ion concentrations: SID=[Na(+)] + [K(+)] - [Cl(-)]-lactate. Regarding the metabolic disturbances of acid-base chemistry, according to Stewart's terminology, changes in pH, [H(+)], and [Bic(-)] are only possible if either SID or [A(-)] itself changes. If, for example, SID decreases (e.g. in case of hyperchloremia), this increase in independent negative charges leads to a decrease in dependent negative charges in terms of [Bic(-)] resulting in acidosis (and vice versa). Therefore, according to Stewart, the decrease in SID during

  18. Carrier Frequency Offset Estimation and I/Q Imbalance Compensation for OFDM Systems

    Directory of Open Access Journals (Sweden)

    M. Omair Ahmad

    2007-01-01

    Full Text Available Two types of radio-frequency front-end imperfections, that is, carrier frequency offset and the inphase/quadrature (I/Q imbalance are considered for orthogonal frequency division multiplexing (OFDM communication systems. A preamble-assisted carrier frequency estimator is proposed along with an I/Q imbalance compensation scheme. The new frequency estimator reveals the relationship between the inphase and the quadrature components of the received preamble and extracts the frequency offset from the phase shift caused by the frequency offset and the cross-talk interference due to the I/Q imbalance. The proposed frequency estimation algorithm is fast, efficient, and robust to I/Q imbalance. An I/Q imbalance estimation/compensation algorithm is also presented by solving a least-square problem formulated using the same preamble as employed for the frequency offset estimation. The computational complexity of the I/Q estimation scheme is further reduced by using part of the short symbols with a little sacrifice in the estimation accuracy. Computer simulation and comparison with some of the existing algorithms are conducted, showing the effectiveness of the proposed method.

  19. Liquidity Effects on the Simultaneity of Trading Volume and Order Imbalance

    Directory of Open Access Journals (Sweden)

    Erman Denny Arfianto

    2016-10-01

    Full Text Available The purpose of this research is to analyze the simultaneity between trading volume and order imbalance, the influence of past performance, market risk, market capitalization, tick size to the trading volume and the influence of tick size, depth and bid-ask spread to the order imbalance of companies that were listed on LQ 45 index. The samples in this research were selected by using the purposive sampling method with some selected criteria. Fifty-five companies listed on 2014’s LQ 45 index were chosen as the sample. The results showed that the trading volume is simultaneously related to the order imbalance; past performance, market risk, and market capitalization have the positive and significant effect to the trading volume; tick size has the negative and significant effect to the trading volume; the order imbalance has the negative and insignificant effect to the trading volume; tick size, depth, bid-ask spread, and trading volume have no significant effect to the order imbalance.

  20. Effort-reward imbalance and organisational injustice among aged nurses: a moderated mediation model.

    Science.gov (United States)

    Topa, Gabriela; Guglielmi, Dina; Depolo, Marco

    2016-09-01

    To test the effort-reward imbalance model among older nurses, expanding it to include the moderation of overcommitment and age in the stress-health complaints relationship, mediated by organisational injustice. The theoretical framework included the effort-reward imbalance, the uncertainty management and the socio-emotional selectivity models. Employing a two-wave design, the participants were 255 nurses aged 45 years and over, recruited from four large hospitals in Spain (Madrid and Basque Country). The direct effect of imbalance on health complaints was supported: it was significant when overcommitment was low but not when it was high. Organisational injustice mediated the influence of effort-reward imbalance on health complaints. The conditional effect of the mediation of organisational injustice was significant in three of the overcommitment/age conditions but it weakened, becoming non-significant, when the level of overcommitment was low and age was high. The study tested the model in nursing populations and expanded it to the settings of occupational health and safety at work. The results of this study highlight the importance of effort-reward imbalance and organisational justice for creating healthy work environments. © 2016 John Wiley & Sons Ltd.

  1. Metabolism, gas exchange, and acid-base balance of giant salamanders.

    Science.gov (United States)

    Ultsch, Gordon R

    2012-08-01

    The giant salamanders are aquatic and paedomorphic urodeles including the genera Andrias and Cryptobranchus (Cryptobranchidae), Amphiuma (Amphiumidae), Siren (Sirenidae), and Necturus (Proteidae, of which only N. maculosus is considered 'a giant'). Species in the genera Cryptobranchus and Necturus are considered aquatic salamanders well adapted for breathing water, poorly adapted for breathing air, and with limited abilities to compensate acid-base disturbances. As such, they are water-breathing animals with a somewhat fish-like respiratory and acid-base physiology, whose habitat selection is limited to waters that do not typically become hypoxic or hypercarbic (although this assertion has been questioned for N. maculosus). Siren and Amphiuma species, by contrast, are dependent upon air-breathing, have excellent lungs, inefficient (Siren) or no (Amphiuma) gills, and are obligate air-breathers with an acid-base status more similar to that of terrestrial tetrapods. As such, they can be considered to be air-breathing animals that live in water. Their response to the aquatic hypercarbia that they often encounter is to maintain intracellular pH (pH(i) ) and abandon extracellular pH regulation, a process that has been referred to as preferential pH(i) regulation. The acid-base status of some present-day tropical air-breathing fishes, and of Siren and Amphiuma, suggests that the acid-base transition from a low PCO(2) -low [] system typical of water-breathing fishes to the high PCO(2) -high [] systems of terrestrial tetrapods may have been completed before emergence onto land, and likely occurred in habitats that were typically both hypoxic and hypercarbic. © 2011 The Author. Biological Reviews © 2011 Cambridge Philosophical Society.

  2. Thioarsenides: A case for long-range Lewis acid-base-directed van der Waals interactions

    Energy Technology Data Exchange (ETDEWEB)

    Gibbs, Gerald V.; Wallace, Adam F.; Downs, R. T.; Ross, Nancy L.; Cox, David F.; Rosso, Kevin M.

    2011-04-01

    Electron density distributions, bond paths, Laplacian and local energy density properties have been calculated for a number of As4Sn (n = 3,4,5) thioarsenide molecular crystals. On the basis of the distributions, the intramolecular As-S and As-As interactions classify as shared bonded interactions and the intermolecular As-S, As-As and S-S interactions classify as closed-shell van der Waals bonded interactions. The bulk of the intermolecular As-S bond paths link regions of locally concentrated electron density (Lewis base regions) with aligned regions of locally depleted electron density (Lewis acid regions) on adjacent molecules. The paths are comparable with intermolecular paths reported for several other molecular crystals that link aligned Lewis base and acid regions in a key-lock fashion, interactions that classified as long range Lewis acid-base directed van der Waals interactions. As the bulk of the intermolecular As-S bond paths (~70%) link Lewis acid-base regions on adjacent molecules, it appears that molecules adopt an arrangement that maximizes the number of As-S Lewis acid-base intermolecular bonded interactions. The maximization of the number of Lewis acid-base interactions appears to be connected with the close-packed array adopted by molecules: distorted cubic close-packed arrays are adopted for alacránite, pararealgar, uzonite, realgar and β-AsS and the distorted hexagonal close-packed arrays adopted by α- and β-dimorphite. A growth mechanism is proposed for thioarsenide molecular crystals from aqueous species that maximizes the number of long range Lewis acid-base vdW As-S bonded interactions with the resulting directed bond paths structuralizing the molecules as a molecular crystal.

  3. Thioarsenides: a case for long-range Lewis acid-base-directed van der Waals interactions

    Science.gov (United States)

    Gibbs, G. V.; Wallace, A. F.; Downs, R. T.; Ross, N. L.; Cox, D. F.; Rosso, K. M.

    2011-04-01

    Electron density distributions, bond paths, Laplacian and local-energy density properties have been calculated for a number of As4S n ( n = 3, 4 and 5) thioarsenide molecular crystals. On the basis of the distributions, the intramolecular As-S and As-As interactions classify as shared bonded interactions, and the intermolecular As-S, As-As and S-S interactions classify as closed-shell van der Waals (vdW) bonded interactions. The bulk of the intermolecular As-S bond paths link regions of locally concentrated electron density (Lewis-base regions) with aligned regions of locally depleted electron density (Lewis-acid regions) on adjacent molecules. The paths are comparable with intermolecular paths reported for several other molecular crystals that link aligned Lewis base and acid regions in a key-lock fashion, interactions that classified as long-range Lewis acid-base-directed vdW interactions. As the bulk of the intermolecular As-S bond paths (~70%) link Lewis acid-base regions on adjacent molecules, it appears that molecules adopt an arrangement that maximizes the number of As-S Lewis acid-base intermolecular bonded interactions. The maximization of the number of Lewis acid-base interactions appears to be connected with the close-packed array adopted by molecules: distorted cubic close-packed arrays are adopted for alacránite, pararealgar, uzonite, realgar and β-AsS and the distorted hexagonal close-packed arrays adopted by α- and β-dimorphite. A growth mechanism is proposed for thioarsenide molecular crystals from aqueous species that maximizes the number of long-range Lewis acid-base vdW As-S bonded interactions with the resulting directed bond paths structuralizing the molecules as a molecular crystal.

  4. Asynchronous Cholinergic Drive Correlates with Excitation-Inhibition Imbalance via a Neuronal Ca2+ Sensor Protein

    Directory of Open Access Journals (Sweden)

    Keming Zhou

    2017-05-01

    Full Text Available Excitation-inhibition imbalance in neural networks is widely linked to neurological and neuropsychiatric disorders. However, how genetic factors alter neuronal activity, leading to excitation-inhibition imbalance, remains unclear. Here, using the C. elegans locomotor circuit, we examine how altering neuronal activity for varying time periods affects synaptic release pattern and animal behavior. We show that while short-duration activation of excitatory cholinergic neurons elicits a reversible enhancement of presynaptic strength, persistent activation results to asynchronous and reduced cholinergic drive, inducing imbalance between endogenous excitation and inhibition. We find that the neuronal calcium sensor protein NCS-2 is required for asynchronous cholinergic release in an activity-dependent manner and dampens excitability of inhibitory neurons non-cell autonomously. The function of NCS-2 requires its Ca2+ binding and membrane association domains. These results reveal a synaptic mechanism implicating asynchronous release in regulation of excitation-inhibition balance.

  5. Evolutionary Cluster-Based Synthetic Oversampling Ensemble (ECO-Ensemble) for Imbalance Learning.

    Science.gov (United States)

    Lim, Pin; Goh, Chi Keong; Tan, Kay Chen

    2017-09-01

    Class imbalance problems, where the number of samples in each class is unequal, is prevalent in numerous real world machine learning applications. Traditional methods which are biased toward the majority class are ineffective due to the relative severity of misclassifying rare events. This paper proposes a novel evolutionary cluster-based oversampling ensemble framework, which combines a novel cluster-based synthetic data generation method with an evolutionary algorithm (EA) to create an ensemble. The proposed synthetic data generation method is based on contemporary ideas of identifying oversampling regions using clusters. The novel use of EA serves a twofold purpose of optimizing the parameters of the data generation method while generating diverse examples leveraging on the characteristics of EAs, reducing overall computational cost. The proposed method is evaluated on a set of 40 imbalance datasets obtained from the University of California, Irvine, database, and outperforms current state-of-the-art ensemble algorithms tackling class imbalance problems.

  6. Thermal imbalance force modelling for a GPS satellite using the finite element method

    Science.gov (United States)

    Vigue, Yvonne; Schutz, Bob E.

    1991-01-01

    Methods of analyzing the perturbation due to thermal radiation and determining its effects on the orbits of GPS satellites are presented, with emphasis on the FEM technique to calculate satellite solar panel temperatures which are used to determine the magnitude and direction of the thermal imbalance force. Although this force may not be responsible for all of the force mismodeling, conditions may work in combination with the thermal imbalance force to produce such accelerations on the order of 1.e-9 m/sq s. If submeter accurate orbits and centimeter-level accuracy for geophysical applications are desired, a time-dependent model of the thermal imbalance force should be used, especially when satellites are eclipsing, where the observed errors are larger than for satellites in noneclipsing orbits.

  7. Distinct evolutionary mechanisms for genomic imbalances in high-risk and low-risk neuroblastomas

    Directory of Open Access Journals (Sweden)

    Øra Ingrid

    2007-01-01

    Full Text Available Abstract Background Neuroblastoma (NB is the most common extracranial solid tumour of childhood. Several genomic imbalances correlate to prognosis in NB, with structural rearrangements, including gene amplification, in a near-diploid setting typically signifying high-risk tumours and numerical changes in a near-triploid setting signifying low-risk tumours. Little is known about the temporal sequence in which these imbalances occur during the carcinogenic process. Methods We have reconstructed the appearance of cytogenetic imbalances in 270 NBs by first grouping tumours and imbalances through principal component analysis and then using the number of imbalances in each tumour as an indicator of evolutionary progression. Results Tumours clustered in four sub-groups, dominated respectively by (1 gene amplification in double minute chromosomes and few other aberrations, (2 gene amplification and loss of 1p sequences, (3 loss of 1p and other structural aberrations including gain of 17q, and (4 whole-chromosome gains and losses. Temporal analysis showed that the structural changes in groups 1–3 were acquired in a step-wise fashion, with loss of 1p sequences and the emergence of double minute chromosomes as the earliest cytogenetic events. In contrast, the gains and losses of whole chromosomes in group 4 occurred through multiple simultaneous events leading to a near-triploid chromosome number. Conclusion The finding of different temporal patterns for the acquisition of genomic imbalances in high-risk and low-risk NBs lends strong support to the hypothesis that these tumours are biologically diverse entities, evolving through distinct genetic mechanisms.

  8. What is Driving Global Imbalances? The Global Savings Glut Hypothesis Reexamined

    Directory of Open Access Journals (Sweden)

    Jai-Won Ryou

    2009-12-01

    Full Text Available In the middle of the global financial crisis, global imbalances seem to have been resolved to some extent, but it remains to be seen whether these imbalances will emerge again along with economic recovery. In order to cope with this global issue, we need to clarify what caused global imbalances in the first place. This paper aims to evaluate the relative importance of the "global savings glut" to the U.S. external imbalances. Drawing on the portfolio balance model, we analyze how the process of interaction between the U.S. current account deficit, capital inflows, and the U.S. dollar exchange rate is linked to domestic and external factors. Our empirical analysis shows that the U.S. current account deficit maintained since the early 1990s is mainly driven by the domestic factors, such as a decrease in the U.S. national savings and an increase in money supply growth. The size of the negative effect of a "global savings glut" measured by an increase in the East Asian countries' national savings (i.e. China, Japan and Korea on the U.S. current account seems to be exaggerated. Meanwhile, current account does not appear to be sensitive to changes in the exchange rate. This finding implies that the rectification of global imbalances is hardly possible to achieve by means of depreciating the U.S. dollar alone while leaving the structural factors unchanged. In order to achieve global rebalancing, the U.S. should increase its savings rate, reduce fiscal deficit, and tighten its money supply. While an increase in the domestic demand in the surplus countries such as China and Japan may be helpful in rectifying global imbalances, it appears to be insufficient per se.

  9. Determinants of Pre-Operative Shoulder Imbalance in Patients with Adolescent Idiopathic Scoliosis

    Directory of Open Access Journals (Sweden)

    Hassan Ghandhari

    2017-01-01

    Full Text Available Background Disfiguring complications of adolescent idiopathic scoliosis (AIS could significantly affect the patients’ satisfaction. In this regard, shoulder imbalance has recently received much attention in spite of its poorly understood challenge. Objectives While the majority of previous studies have attempted to explore preoperative determinants of postoperative shoulder imbalance, in this study we aimed to investigate the factors correlated with the preoperative shoulder imbalance. Methods A total of 72 AIS patients with no previous history of corrective surgery took part in this study. The study sample comprised 63 females and 9 males with the mean age of 15.72 ± 3.08 years, ranging from 11 to 26 years. Shoulder imbalance parameters including T1 tilt, first rib angle (FRA, and clavicle angle (CA were assessed and their correlation with radiographic characteristics of the curves and patients’ demographic data including age and sex was evaluated. Results T1 tilt was more severe in males (mean -8.2° than females (mean -2.8° (P = 0.04. Moreover, a significant correlation was found between age and FRA (P = 0.04. A significant correlation was also observed between main thoracic (MT curve size and all the three parameters of shoulder imbalance (P < 0.001. The reverse correlation of T5 - T12 kyphosis angle with FRA was also significant (P = 0.04. Conclusions According to our results, in AIS, pre-operative radiographic shoulder imbalance could be affected by some curve parameters including MT and kyphosis size and demographic characteristics of patients including age and gender.

  10. Multi-hop amplify-and-forward relaying cooperation in the presence of I/Q imbalance

    KAUST Repository

    Qi, Jian

    2013-06-01

    In this paper, multi-hop cooperative networks implementing channel state information (CSI)-assisted amplify-and-forward (AF) relaying in the presence of in-phase and quadrature-phase (I/Q) imbalance are investigated. We propose a compensation algorithm for the I/Q imbalance. The performance of the multi-hop CSI-assisted AF cooperative networks with and without compensation for I/Q imbalance in Nakagami-m fading environment is evaluated in terms of average symbol error probability. Numerical results are provided and show that the proposed compensation method can effectively mitigate the impact of I/Q imbalance. © 2013 IEEE.

  11. Electrolyte imbalance and sleep problems during anti-retroviral therapy: an under-recognized problem

    Directory of Open Access Journals (Sweden)

    Md Dilshad Manzar

    Full Text Available Human immunodeficiency virus (HIV infection, and the anti-retroviral therapy (ART associated complications necessitate that the medical care system keeps evolving for proper management of this group of patients. Electrolyte imbalance and sleep problems are common in patients on ART. Both of these conditions are associated with increased morbidity (such as acute kidney injury, chronic kidney disease, low CD4 count, non-adherence and depression and mortality. Therefore, screening for both sleep problems and electrolytes imbalance may help to decrease the risk of complications in patients on ART.

  12. Electrolyte imbalance and sleep problems during anti-retroviral therapy: an under-recognized problem.

    Science.gov (United States)

    Manzar, Md Dilshad; Sony, Peter; Salahuddin, Mohammed; Kumalo, Abera; Geneto, Mathewos; Pandi-Perumal, Seithikurippu R; Moscovitch, Adam; BaHammam, Ahmed S

    2017-01-01

    Human immunodeficiency virus (HIV) infection, and the anti-retroviral therapy (ART) associated complications necessitate that the medical care system keeps evolving for proper management of this group of patients. Electrolyte imbalance and sleep problems are common in patients on ART. Both of these conditions are associated with increased morbidity (such as acute kidney injury, chronic kidney disease, low CD4 count, non-adherence and depression) and mortality. Therefore, screening for both sleep problems and electrolytes imbalance may help to decrease the risk of complications in patients on ART.

  13. CONTROL PARAMETERS FOR UNDERSTANDING AND PREVENTING PROCESS IMBALANCES IN BIOGAS PLANTS. EMPHAS IS ON VFA DYNAMICS

    DEFF Research Database (Denmark)

    Bangsø Nielsen, Henrik

    H. The experiments were carried out in lab-scale thermophilic continuously stirred tank reactors (CSTR) treating livestock waste. The imbalances included inhibition by long chain fatty acids (LCFA), inhibition by ammonia, organic overloading with proteins and organic overloading with industrial waste, i.e. meat...... and bone meal and lipids. During the main part of the experiments one reactor was connected to an online VFA sensor giving a detailed profile of the VFA dynamics during the process imbalances. Based on the results it was concluded, that propionate was the most reliable single parameter for indication...

  14. Imbalance in resting state functional connectivity is associated with eating behaviors and adiposity in children

    Directory of Open Access Journals (Sweden)

    BettyAnn A. Chodkowski

    2016-01-01

    Conclusions: In the absence of any explicit eating-related stimuli, the developing brain is primed toward food approach and away from food avoidance behavior with increasing adiposity. Imbalance in resting state functional connectivity that is associated with non-homeostatic eating develops during childhood, as early as 8–13 years of age. Our results indicate the importance of identifying children at risk for obesity for earlier intervention. In addition to changing eating habits and physical activity, strategies that normalize neural functional connectivity imbalance are needed to maintain healthy weight. Mindfulness may be one such approach as it is associated with increased response inhibition and decreased impulsivity.

  15. Cerebral (31)P magnetic resonance spectroscopy and systemic acid-base balance during hypoxia in fetal sheep.

    NARCIS (Netherlands)

    Cappellen van Walsum, A.M. van; Rijpkema, M.J.P.; Heerschap, A.; Oeseburg, B.; Nijhuis, J.G.; Jongsma, H.W.

    2003-01-01

    The purpose of this study was to investigate cerebral energy metabolism and acid-base homeostasis during impaired oxygen supply in fetal sheep. Systemic acid-base balance was correlated with the sequence in changes of cerebral phosphorus metabolite ratios and intracellular pH. Phosphorus magnetic

  16. Bicarbonate sensing in mouse cortical astrocytes during extracellular acid/base disturbances.

    Science.gov (United States)

    Theparambil, Shefeeq M; Naoshin, Zinnia; Defren, Sabrina; Schmaelzle, Jana; Weber, Tobias; Schneider, Hans-Peter; Deitmer, Joachim W

    2017-04-15

    The present study suggests that the electrogenic sodium-bicarbonate cotransporter, NBCe1, supported by carbonic anhydrase II, CAII, provides an efficient mechanism of bicarbonate sensing in cortical astrocytes. This mechanism is proposed to play a major role in setting the pHi responses to extracellular acid/base challenges in astrocytes. A decrease in extracellular [HCO3(-) ] during isocapnic acidosis and isohydric hypocapnia, or an increase in intracellular [HCO3(-) ] during hypercapnic acidosis, was effectively sensed by NBCe1, which carried bicarbonate out of the cells under these conditions, and caused an acidification and sodium fall in WT astrocytes, but not in NBCe1-knockout astrocytes. Isocapnic acidosis, hypercapnic acidosis and isohydric hypocapnia evoked inward currents in NBCe1- and CAII-expressing Xenopus laevis oocytes, but not in native oocytes, suggesting that NBCe1 operates in the outwardly directed mode under these conditions consistent with our findings in astrocytes. We propose that bicarbonate sensing of astrocytes may have functional significance during extracellular acid/base disturbances in the brain, as it not only alters intracellular pH/[HCO3(-) ]-dependent functions of astrocytes, but also modulates the extracellular pH/[HCO3(-) ] in brain tissue. Extracellular acid/base status of the mammalian brain undergoes dynamic changes during many physiological and pathological events. Although intracellular pH (pHi ) of astrocytes responds to extracellular acid/base changes, the mechanisms mediating these changes have remained unresolved. We have previously shown that the electrogenic sodium-bicarbonate cotransporter, NBCe1, is a high-affinity bicarbonate carrier in cortical astrocytes. In the present study, we investigated whether NBCe1 plays a role in bicarbonate sensing in astrocytes, and in determining the pHi responses to extracellular acid/base challenges. We measured changes in intracellular H(+) and Na(+) in astrocytes from wild-type (WT

  17. Optical Absorption and Electron Injection of 4-(Cyanomethylbenzoic Acid Based Dyes: A DFT Study

    Directory of Open Access Journals (Sweden)

    Yuehua Zhang

    2015-01-01

    Full Text Available Density functional theory (DFT and time-dependent density functional theory (TDDFT calculations were carried out to study the ground state geometries, electronic structures, and absorption spectra of 4-(cyanomethylbenzoic acid based dyes (AG1 and AG2 used for dye-sensitized solar cells (DSSCs. The excited states properties and the thermodynamical parameters of electron injection were studied. The results showed that (a two dyes have uncoplanar structures along the donor unit and conjugated bridge space, (b two sensitizers exhibited intense absorption in the UV-Vis region, and (c the excited state oxidation potential was higher than the conduction band edge of TiO2 photoanode. As a result, a solar cell based on the 4-(cyanomethylbenzoic acid based dyes exhibited well photovoltaic performance. Furthermore, nine dyes were designed on the basis of AG1 and AG2 to improve optical response and electron injection.

  18. Quantitative physical chemistry analysis of acid-base disorders in critically ill patients.

    Science.gov (United States)

    Story, D A; Poustie, S; Bellomo, R

    2001-06-01

    Compared with the Henderson-Hasselbalch approach, the Stewart approach may better describe the mechanisms of acid-base physiology and disorders. We prospectively examined the acid-base disorders of 100 routine blood samples from critically ill patients using Stewart's physical chemistry analysis. The median results were pH 7.45, PaCO2 5.5 kPa, bicarbonate 27.2 mmol.l-1 and base excess 3 mmol.l-1. The median reference strong ion difference was 46.0 meq.l-1 and the measured median was 45.5 meq.l-1. The median reference total weak-acid concentration was 11.1 mmol.l-1. The measured median total weak-acid concentration was 6.8 mmol.l-1. From Stewart's approach, the most likely explanation for the overall alkalosis was decreased total weak-acid concentration resulting from decreased plasma albumin concentration.

  19. Clinical observations and acid-base imbalances in sheep during chronic copper poisoningAvaliação clínica e hemogasométrica de ovinos com intoxicação cúprica acumulativa

    Directory of Open Access Journals (Sweden)

    Clara Satsuk Mori

    2011-08-01

    Full Text Available Twelve male sheep were intoxicated with copper and four served as controls. When hemoglobinuria was first diagnosed, the poisoned sheep were randomly distributed into two groups: 4 untreated and 8 tetratiomolybdate-treated. Blood samples and clinical evaluation were performed daily, from the onset of poisoning until the 30th day. Analysis of packed cell volume, plasma free hemoglobin, and blood gas were made. Elevated heart rates and rectal temperature, and reduced respiratory and ruminal movement rates were recorded in the intoxicated group. The poisoned sheep developed mild alkalosis caused by bicarbonate retention, while a short-periodic increase of pCO2 occurred to compensate the ongoing alkalosis. Elevated degree of anemia was directly proportional to heart rate, while high degree of alkalosis was inversely proportional to respiratory rate. Further, there was an elevated positive relationship between plasma free hemoglobin and rectal temperature, and an increase in rectal temperature accompanied a reduced ruminal movement.Foram utilizados 16 cordeiros, sendo 12 submetidos à intoxicação cúprica e quatro animais controle. Quando foi verificada a presença de hemoglobinúria, os animais intoxicados foram aleatoriamente distribuídos em dois grupos, quatro animais não tratados e oito animais tratados com tetratiomolybidato de amônia. Foi realizado exame clínico e coleta de sangue diariamente desde o início da intoxicação até 30 dias após. Foram analisados o volume globular, concentração de hemoglobina plasmática e avaliação hemogasométrica. Nos animais intoxicados, foi observado elevação da freqüência cardíaca e da temperatura retal e redução da freqüência respiratória e dos movimentos ruminais. Os ovinos intoxicados desenvolveram alcalose moderada causada por retenção de bicarbonato seguido de um aumento pontual da pCO2 para compensar a alcalose em curso. Quanto maior o grau de anemia foi maior a freqüência cardíaca, enquanto que quanto maior o grau de alcalose menor a freqüência respiratória. Houve uma relação positiva entre a elevação da hemoglobina plasmática livre e a temperatura retal, e quanto maior a temperatura retal menor a freqüência de movimentos ruminais.

  20. Clinical utility of serum biochemical variables for predicting acid-base balance in critically ill horses.

    Science.gov (United States)

    Stämpfli, Henry R; Schoster, Angelika; Constable, Peter D

    2014-12-01

    Profiles from serum biochemical analyzers include the concentration of strong electrolytes (including l-lactate), total carbon dioxide (tCO2 ), and total protein. These variables are associated with changes in acid-base balance. Application of physicochemical principles may allow predicting acid-base balance from serum biochemistry without measuring whole blood pH and pCO2 . The purpose of the study was to determine if the acid-base status of critically ill horses could be accurately predicted using variables included in standard serum biochemical profiles. Two jugular venous blood samples were prospectively obtained from critically ill horses and foals. Samples were analyzed using a whole blood gas and pH analyzer (BG) and a serum biochemistry multi analyzer system (AMAS). Linear regression, Deming regression, and Bland-Altman plots were used for method comparison and P acid base interpretation, were different between the AMAS and BG analyzer. Using physicochemical principles, BG results accurately predicted pH, whereas the AMAS results did not when a fixed value for pCO2 was used. Measurement of pCO2 is required in critically ill horses for accurate prediction of whole blood pH. Differences in the measured values of Na and Cl concentration exist when measured in serum by the AMAS and in whole blood or plasma by BG, indicating that the accurate prediction of whole blood pH is analyzer-dependent. Application of physicochemical principles to plasma or serum provides a practical method to evaluate analyzer accuracy. © 2014 American Society for Veterinary Clinical Pathology.

  1. Acid-base and ion balance in fishes with bimodal respiration.

    Science.gov (United States)

    Shartau, R B; Brauner, C J

    2014-03-01

    The evolution of air breathing during the Devonian provided early fishes with bimodal respiration with a stable O2 supply from air. This was, however, probably associated with challenges and trade-offs in terms of acid-base balance and ionoregulation due to reduced gill:water interaction and changes in gill morphology associated with air breathing. While many aspects of acid-base and ionoregulation in air-breathing fishes are similar to water breathers, the specific cellular and molecular mechanisms involved remain largely unstudied. In general, reduced ionic permeability appears to be an important adaptation in the few bimodal fishes investigated but it is not known if this is a general characteristic. The kidney appears to play an important role in minimizing ion loss to the freshwater environment in the few species investigated, and while ion uptake across the gut is probably important, it has been largely unexplored. In general, air breathing in facultative air-breathing fishes is associated with an acid-base disturbance, resulting in an increased partial pressure of arterial CO2 and a reduction in extracellular pH (pHE ); however, several fishes appear to be capable of tightly regulating tissue intracellular pH (pHI ), despite a large sustained reduction in pHE , a trait termed preferential pHI regulation. Further studies are needed to determine whether preferential pHI regulation is a general trait among bimodal fishes and if this confers reduced sensitivity to acid-base disturbances, including those induced by hypercarbia, exhaustive exercise and hypoxia or anoxia. Additionally, elucidating the cellular and molecular mechanisms may yield insight into whether preferential pHI regulation is a trait ultimately associated with the early evolution of air breathing in vertebrates. © 2014 The Fisheries Society of the British Isles.

  2. Hyperventilation and blood acid-base balance in hypercapnia exposed red drum (Sciaenops ocellatus).

    Science.gov (United States)

    Ern, Rasmus; Esbaugh, Andrew J

    2016-05-01

    Hyperventilation is a common response in fish exposed to elevated water CO2. It is believed to lessen the respiratory acidosis associated with hypercapnia by lowering arterial PCO2, but the contribution of hyperventilation to blood acid-base compensation has yet to be quantified. Hyperventilation may also increase the flux of irons across the gill epithelium and the cost of osmoregulation, owing to the osmo-respiratory compromise. Therefore, hypercapnia exposed fish may increase standard metabolic rate (SMR) leaving less energy for physiological functions such as foraging, migration, growth and reproduction. Here we show that gill ventilation, blood PCO2 and total blood [CO2] increased in red drum (Sciaenops ocellatus) exposed to 1000 and 5000 µatm water CO2, and that blood PCO2 and total blood [CO2] decrease in fish during hypoxia induced hyperventilation. Based on these results we estimate the ventilatory contributions to total acid-base compensation in 1000 and 5000 µatm water CO2. We find that S. ocellatus only utilize a portion of its ventilatory capacity to reduce the acid-base disturbance in 1000 µatm water CO2. SMR was unaffected by both salinity and hypercapnia exposure indicating that the cost of osmoregulation is small relative to SMR, and that the lack of increased ventilation in 1000 µatm water CO2 despite the capacity to do so is not due to an energetic tradeoff between acid-base balance and osmoregulation. Therefore, while ocean acidification may impact ventilatory parameters, there will be little impact on the overall energy budget of S. ocellatus.

  3. Acid-base properties of humic and fulvic acids formed during composting.

    Science.gov (United States)

    Plaza, César; Senesi, Nicola; Polo, Alfredo; Brunetti, Gennaro

    2005-09-15

    The soil acid-base buffering capacity and the biological availability, mobilization, and transport of macro- and micronutrients, toxic metal ions, and xenobiotic organic cations in soil are strongly influenced by the acid-base properties of humic substances, of which humic and fulvic acids are the major fractions. For these reasons, the proton binding behavior of the humic acid-like (HA) and fulvic acid-like (FA) fractions contained in a compost are believed to be instrumental in its successful performance in soil. In this work, the acid-base properties of the HAs and FAs isolated from a mixture of the sludge residue obtained from olive oil mill wastewater (OMW) evaporated in an open-air pond and tree cuttings (TC) at different stages of composting were investigated by a current potentiometric titration method and the nonideal competitive adsorption (NICA)-Donnan model. The NICA-Donnan model provided an excellent description of the acid-base titration data, and pointed out substantial differences in site density and proton-binding affinity between the HAs and FAs examined. With respect to FAs, HAs were characterized by a smaller content of carboxylic- and phenolic-type groups and their larger affinities for proton binding. Further, HAs featured a greater heterogeneity in carboxylic-type groups than FAs. The composting process increased the content and decreased the proton affinity of carboxylic- and phenolic-type groups of HAs and FAs, and increased the heterogeneity of phenolic-type groups of HAs. As a whole, these effects indicated that the composting process could produce HA and FA fractions with greater cation binding capacities. These results suggest that composting of organic materials improves their agronomic and environmental value by increasing their potential to retain and exchange macro- and micronutrients, and to reduce the bioavailability of organic and inorganic pollutants.

  4. Acid-base and electrolyte disorders in patients with diabetes mellitus

    Directory of Open Access Journals (Sweden)

    Nikolaos Sotirakopoulos

    2012-01-01

    Full Text Available Diabetes mellitus is the most common metabolic disorder in the community. The diabetics may suffer from acid-base and electrolyte disorders due to complications of diabetes mellitus and the medication they receive. In this study, acid-base and electrolyte disorders were evaluated among outpatient diabetics in our hospital. The study consisted of patients with diabetes mellitus who visited the hospital as outpatients between the period January 1, 2004 to December 31, 2006. The patients′ medical history, age and type of diabetes were noted, including whether they were taking diuretics and calcium channel blockers or not. Serum creatinine, proteins, sodium, potassium and chloride and blood gases were measured in all patients. Proteinuria was measured by 24-h urine collection. Two hundred and ten patients were divided in three groups based on the serum creatinine. Group A consisted of 114 patients that had serum creatinine 3.1 mg/dL. Of the 210 patients, 176 had an acid-base disorder. The most common disorder noted in group A was metabolic alkalosis. In groups B and C, the common disorders were metabolic acidosis and alkalosis, and metabolic acidosis, respectively. The most common electrolyte disorders were hypernatremia (especially in groups A and B, hyponatremia (group C and hyperkalemia (especially in groups B and C. It is concluded that: (a in diabetic outpatients, acid-base and electrolyte disorders occurred often even if the renal function is normal, (b the most common disorders are metabolic alkalosis and metabolic acidosis (the frequency increases with the deterioration of the renal function and (c the common electrolyte disorders are hypernatremia and hypokalemia.

  5. Acid-base status in the avian patient using a portable point-of-care analyzer.

    Science.gov (United States)

    Montesinos, Andrés; Ardiaca, María

    2013-01-01

    The i-STAT PCA can be used as a blood analyzer in critical avian patients, although single values must be interpreted carefully. The study of the acid-base status in companion birds is still in its infancy. Further research is needed to establish normal reference values in arterial blood gases, compare them with venous blood gas, and to determine if the formulas that deviate from small animal medicine are or are not applicable. Copyright © 2013 Elsevier Inc. All rights reserved.

  6. Influence of dissolved organic carbon content on modelling natural organic matter acid-base properties.

    Science.gov (United States)

    Garnier, Cédric; Mounier, Stéphane; Benaïm, Jean Yves

    2004-10-01

    Natural organic matter (NOM) behaviour towards proton is an important parameter to understand NOM fate in the environment. Moreover, it is necessary to determine NOM acid-base properties before investigating trace metals complexation by natural organic matter. This work focuses on the possibility to determine these acid-base properties by accurate and simple titrations, even at low organic matter concentrations. So, the experiments were conducted on concentrated and diluted solutions of extracted humic and fulvic acid from Laurentian River, on concentrated and diluted model solutions of well-known simple molecules (acetic and phenolic acids), and on natural samples from the Seine river (France) which are not pre-concentrated. Titration experiments were modelled by a 6 acidic-sites discrete model, except for the model solutions. The modelling software used, called PROSECE (Programme d'Optimisation et de SpEciation Chimique dans l'Environnement), has been developed in our laboratory, is based on the mass balance equilibrium resolution. The results obtained on extracted organic matter and model solutions point out a threshold value for a confident determination of the studied organic matter acid-base properties. They also show an aberrant decreasing carboxylic/phenolic ratio with increasing sample dilution. This shift is neither due to any conformational effect, since it is also observed on model solutions, nor to ionic strength variations which is controlled during all experiments. On the other hand, it could be the result of an electrode troubleshooting occurring at basic pH values, which effect is amplified at low total concentration of acidic sites. So, in our conditions, the limit for a correct modelling of NOM acid-base properties is defined as 0.04 meq of total analysed acidic sites concentration. As for the analysed natural samples, due to their high acidic sites content, it is possible to model their behaviour despite the low organic carbon concentration.

  7. Whole body acid-base and fluid-electrolyte balance: a mathematical model.

    Science.gov (United States)

    Wolf, Matthew B

    2013-10-15

    A cellular compartment was added to our previous mathematical model of steady-state acid-base and fluid-electrolyte chemistry to gain further understanding and aid diagnosis of complex disorders involving cellular involvement in critically ill patients. An important hypothesis to be validated was that the thermodynamic, standard free-energy of cellular H(+) and Na(+) pumps remained constant under all conditions. In addition, a hydrostatic-osmotic pressure balance was assumed to describe fluid exchange between plasma and interstitial fluid, including incorporation of compliance curves of vascular and interstitial spaces. The description of the cellular compartment was validated by close comparison of measured and model-predicted cellular pH and electrolyte changes in vitro and in vivo. The new description of plasma-interstitial fluid exchange was validated using measured changes in fluid volumes after isoosmotic and hyperosmotic fluid infusions of NaCl and NaHCO3. The validated model was used to explain the role of cells in the mechanism of saline or dilutional acidosis and acid-base effects of acidic or basic fluid infusions and the acid-base disorder due to potassium depletion. A module was created that would allow users, who do not possess the software, to determine, for free, the results of fluid infusions and urinary losses of water and solutes to the whole body.

  8. Extracellular Acid-Base Balance and Ion Transport Between Body Fluid Compartments.

    Science.gov (United States)

    Seifter, Julian L; Chang, Hsin-Yun

    2017-09-01

    Clinical assessment of acid-base disorders depends on measurements made in the blood, part of the extracellular compartment. Yet much of the metabolic importance of these disorders concerns intracellular events. Intracellular and interstitial compartment acid-base balance is complex and heterogeneous. This review considers the determinants of the extracellular fluid pH related to the ion transport processes at the interface of cells and the interstitial fluid, and between epithelial cells lining the transcellular contents of the gastrointestinal and urinary tracts that open to the external environment. The generation of acid-base disorders and the associated disruption of electrolyte balance are considered in the context of these membrane transporters. This review suggests a process of internal and external balance for pH regulation, similar to that of potassium. The role of secretory gastrointestinal epithelia and renal epithelia with respect to normal pH homeostasis and clinical disorders are considered. Electroneutrality of electrolytes in the ECF is discussed in the context of reciprocal changes in Cl- or non Cl- anions and [Formula: see text]. Copyright © 2017 the American Physiological Society.

  9. Biodegradation and Osteosarcoma Cell Cultivation on Poly(aspartic acid) Based Hydrogels.

    Science.gov (United States)

    Juriga, Dávid; Nagy, Krisztina; Jedlovszky-Hajdú, Angéla; Perczel-Kovách, Katalin; Chen, Yong Mei; Varga, Gábor; Zrínyi, Miklós

    2016-09-14

    Development of novel biodegradable and biocompatible scaffold materials with optimal characteristics is important for both preclinical and clinical applications. The aim of the present study was to analyze the biodegradability of poly(aspartic acid)-based hydrogels, and to test their usability as scaffolds for MG-63 osteoblast-like cells. Poly(aspartic acid) was fabricated from poly(succinimide) and hydrogels were prepared using natural amines as cross-linkers (diaminobutane and cystamine). Disulfide bridges were cleaved to thiol groups and the polymer backbone was further modified with RGD sequence. Biodegradability of the hydrogels was evaluated by experiments on the base of enzymes and cell culture medium. Poly(aspartic acid) hydrogels possessing only disulfide bridges as cross-links proved to be degradable by collagenase I. The MG-63 cells showed healthy, fibroblast-like morphology on the double cross-linked and RGD modified hydrogels. Thiolated poly(aspartic acid) based hydrogels provide ideal conditions for adhesion, survival, proliferation, and migration of osteoblast-like cells. The highest viability was found on the thiolated PASP gels while the RGD motif had influence on compacted cluster formation of the cells. These biodegradable and biocompatible poly(aspartic acid)-based hydrogels are promising scaffolds for cell cultivation.

  10. A method for improving the calculation accuracy of acid-base constants by inverse gas chromatography.

    Science.gov (United States)

    Shi, Baoli; Qi, Dawei

    2012-03-30

    In this paper, studies were conducted in order to improve the calculation accuracy of acid-base constants measured by inverse gas chromatography. The conventional a·(γ(d)(l))(0.5) parameters of DCM (dichloromethane), TCM (trichloromethane), and EtAcet (ethyl acetate) were corrected as 185, 212, and 235 Å(2)(mJ/m(2))(0.5) by analyzing the relationship between a·(γ(d)(l))(0.5) and the boiling temperature of the probe solvents, where a is molecular area and γ(l)(d) is surface dispersive free energy of the probe solvents, respectively. To validate the availability of the new a·(γ(d)(l))(0.5) values, the acid-base constants of polystyrene were measured. It was found that when the new a·(γ(d)(l))(0.5) parameters were adopted, the final linear fit degree for the plot of -ΔH(a)(s)/AN* versus DN/AN* was enhanced from 0.993 to 0.999, and the standard deviation was decreased from 0.344 to 0.156. In addition, the availability of general application to improving the calculation accuracy of acid-base constants with the new a·(γ(d)(l))(0.5) parameters was also proved with a mathematical justification. Copyright © 2012 Elsevier B.V. All rights reserved.

  11. Acid-Base Chemistry of White Wine: Analytical Characterisation and Chemical Modelling

    Science.gov (United States)

    Prenesti, Enrico; Berto, Silvia; Toso, Simona; Daniele, Pier Giuseppe

    2012-01-01

    A chemical model of the acid-base properties is optimized for each white wine under study, together with the calculation of their ionic strength, taking into account the contributions of all significant ionic species (strong electrolytes and weak one sensitive to the chemical equilibria). Coupling the HPLC-IEC and HPLC-RP methods, we are able to quantify up to 12 carboxylic acids, the most relevant substances responsible of the acid-base equilibria of wine. The analytical concentration of carboxylic acids and of other acid-base active substances was used as input, with the total acidity, for the chemical modelling step of the study based on the contemporary treatment of overlapped protonation equilibria. New protonation constants were refined (L-lactic and succinic acids) with respect to our previous investigation on red wines. Attention was paid for mixed solvent (ethanol-water mixture), ionic strength, and temperature to ensure a thermodynamic level to the study. Validation of the chemical model optimized is achieved by way of conductometric measurements and using a synthetic “wine” especially adapted for testing. PMID:22566762

  12. α-Ketoglutarate regulates acid-base balance through an intrarenal paracrine mechanism.

    Science.gov (United States)

    Tokonami, Natsuko; Morla, Luciana; Centeno, Gabriel; Mordasini, David; Ramakrishnan, Suresh Krishna; Nikolaeva, Svetlana; Wagner, Carsten A; Bonny, Olivier; Houillier, Pascal; Doucet, Alain; Firsov, Dmitri

    2013-07-01

    Paracrine communication between different parts of the renal tubule is increasingly recognized as an important determinant of renal function. Previous studies have shown that changes in dietary acid-base load can reverse the direction of apical α-ketoglutarate (αKG) transport in the proximal tubule and Henle's loop from reabsorption (acid load) to secretion (base load). Here we show that the resulting changes in the luminal concentrations of αKG are sensed by the αKG receptor OXGR1 expressed in the type B and non-A-non-B intercalated cells of the connecting tubule (CNT) and the cortical collecting duct (CCD). The addition of 1 mM αKG to the tubular lumen strongly stimulated Cl(-)-dependent HCO(3)(-) secretion and electroneutral transepithelial NaCl reabsorption in microperfused CCDs of wild-type mice but not Oxgr1(-/-) mice. Analysis of alkali-loaded mice revealed a significantly reduced ability of Oxgr1(-/-) mice to maintain acid-base balance. Collectively, these results demonstrate that OXGR1 is involved in the adaptive regulation of HCO(3)(-) secretion and NaCl reabsorption in the CNT/CCD under acid-base stress and establish αKG as a paracrine mediator involved in the functional coordination of the proximal and the distal parts of the renal tubule.

  13. Changes in Acid-base balance during simulated soccer match play.

    Science.gov (United States)

    Russell, Mark; Kingsley, Michael I C

    2012-09-01

    This study evaluated changes in markers of acid-base balance that occurred during simulated soccer match play. Sixteen academy soccer players participated in a soccer match simulation that consisted of 90 minutes of soccer-specific exercise with skills throughout. Blood samples were obtained before exercise (preexercise), every 15 minutes during the simulation (15, 30, 45, 60, 75, and 90 minutes), and 10 minutes into the half-time break (half time). Blood lactate concentrations were elevated throughout exercise (preexercise: 1.5 ± 0.12 mmol·L; 90 minutes: 6.1 ± 0.7 mmol·L, time effect: p base excess (preexercise: 2.40 ± 0.54 mmol·L, 90 minutes: -1.57 ± 0.39 mmol·L, time effect = p base excess, and pH recovered at half time (p > 0.05). This is the first study to provide data concerning the acid-base balance of familiarized soccer players during exercise that simulates soccer match play. These findings suggest that (a) blood pH is reduced during soccer-specific exercise and (b) although buffering capacity is reduced throughout exercise, it returns to normal during half time. Further research is warranted to develop interventions that can maintain acid-base balance throughout the full duration of a soccer match.

  14. Contemporary nucleic acid-based molecular techniques for detection, identification, and characterization of Bifidobacterium.

    Science.gov (United States)

    Mianzhi, Yao; Shah, Nagendra P

    2017-03-24

    Bifidobacteria are one of the most important bacterial groups found in the gastrointestinal tract of humans. Medical and food industry researchers have focused on bifidobacteria because of their health-promoting properties. Researchers have historically relied on classic phenotypic approaches (culture and biochemical tests) for detection and identification of bifidobacteria. Those approaches still have values for the identification and detection of some bifidobacterial species, but they are often labor-intensive and time-consuming and can be problematic in differentiating closely related species. Rapid, accurate, and reliable methods for detection, identification, and characterization of bifidobacteria in a mixed bacterial population have become a major challenge. The advent of nucleic acid-based molecular techniques has significantly advanced isolation and detection of bifidobacteria. Diverse nucleic acid-based molecular techniques have been employed, including hybridization, target amplification, and fingerprinting. Certain techniques enable the detection, characterization, and identification at genus-, species-, and strains-levels, whereas others allow typing of species or strains of bifidobacteria. In this review, an overview of methodological principle, technique complexity, and application of various nucleic acid-based molecular techniques for detection, identification, and characterization of bifidobacteria is presented. Advantages and limitations of each technique are discussed, and significant findings based on particular techniques are also highlighted.

  15. Acid-Base Chemistry of White Wine: Analytical Characterisation and Chemical Modelling

    Directory of Open Access Journals (Sweden)

    Enrico Prenesti

    2012-01-01

    Full Text Available A chemical model of the acid-base properties is optimized for each white wine under study, together with the calculation of their ionic strength, taking into account the contributions of all significant ionic species (strong electrolytes and weak one sensitive to the chemical equilibria. Coupling the HPLC-IEC and HPLC-RP methods, we are able to quantify up to 12 carboxylic acids, the most relevant substances responsible of the acid-base equilibria of wine. The analytical concentration of carboxylic acids and of other acid-base active substances was used as input, with the total acidity, for the chemical modelling step of the study based on the contemporary treatment of overlapped protonation equilibria. New protonation constants were refined (L-lactic and succinic acids with respect to our previous investigation on red wines. Attention was paid for mixed solvent (ethanol-water mixture, ionic strength, and temperature to ensure a thermodynamic level to the study. Validation of the chemical model optimized is achieved by way of conductometric measurements and using a synthetic “wine” especially adapted for testing.

  16. Endocrine milieu and erectile dysfunction: is oestradiol-testosterone imbalance, a risk factor in the elderly?

    National Research Council Canada - National Science Library

    Srilatha, Balasubramanian; Adaikan, P Ganesan

    2011-01-01

    ...) in the elderly may well be due to pathophysiological E2T imbalance; the altered hormonal ratio may also explain the higher incidence of ED in hyperestrogenism or following exposure to environmental/plant oestrogens. Asian Journal of Andrology (2011) 13, 569573; doi:10.1038/aja.2010.129; published online 21 March 2011 Keywords: aging; erectil...

  17. Economic concepts to address future water supply-demand imbalances in Iran, Morocco and Saudi Arabia

    NARCIS (Netherlands)

    Hellegers, P.J.G.J.; Immerzeel, W.; Droogers, P.

    2013-01-01

    In Middle East and North Africa (MENA) countries, renewable groundwater and surface water supply are limited while demand for water is growing rapidly. Climate change is expected to increase water demand even further. The main aim of this paper is to evaluate the water supply–demand imbalances in

  18. Economic concepts to address future water supply-demand imbalances in Iran, Morocco and Saudi Arabia

    Science.gov (United States)

    Hellegers, Petra; Immerzeel, Walter; Droogers, Peter

    2013-10-01

    In Middle East and North Africa (MENA) countries, renewable groundwater and surface water supply are limited while demand for water is growing rapidly. Climate change is expected to increase water demand even further. The main aim of this paper is to evaluate the water supply-demand imbalances in Iran, Morocco and Saudi Arabia in 2040-2050 under dry, average and wet climate change projections and to show on the basis of the marginal cost and marginal value of water the optimum mix of supply-side and demand-side adjustments to address the imbalance. A hydrological model has been used to estimate the water supply-demand imbalance. Water supply and demand curves have been used to explore for which (marginal value of) water usage the marginal cost of supply-enhancement becomes too expensive. The results indicate that in the future in all cases, except in Iran under the wet climate projection, the quantity of water demanded has to be reduced considerably to address the imbalance, which is indeed what is currently happening already.

  19. Quasiparticle Lifetime in Ultracold Fermionic Mixtures with Density and Mass Imbalance

    DEFF Research Database (Denmark)

    Lan, Zhihao; Bruun, Georg; Lobo, Carlos

    2013-01-01

    We show that atomic Fermi mixtures with density and mass imbalance exhibit a rich diversity of scaling laws for the quasiparticle decay rate beyond the quadratic energy and temperature dependence of conventional Fermi liquids. For certain densities and mass ratios, the decay rate is linear, where...

  20. Love and fear of heights: the pathophysiology and psychology of height imbalance.

    Science.gov (United States)

    Salassa, John R; Zapala, David A

    2009-01-01

    Individual psychological responses to heights vary on a continuum from acrophobia to height intolerance, height tolerance, and height enjoyment. This paper reviews the English literature and summarizes the physiologic and psychological factors that generate different responses to heights while standing still in a static or motionless environment. Perceptual cues to height arise from vision. Normal postural sway of 2 cm for peripheral objects within 3 m increases as eye-object distance increases. Postural sway >10 cm can result in a fall. A minimum of 20 minutes of peripheral retinal arc is required to detect motion. Trigonometry dictates that a 20-minute peripheral retinal arch can no longer be achieved in a standing position at an eye-object distance of >20 m. At this distance, visual cues conflict with somatosensory and vestibular inputs, resulting in variable degrees of imbalance. Co-occurring deficits in the visual, vestibular, and somatosensory systems can significantly increase height imbalance. An individual's psychological makeup, influenced by learned and genetic factors, can influence reactions to height imbalance. Enhancing peripheral vision and vestibular, proprioceptive, and haptic functions may improve height imbalance. Psychotherapy may improve the troubling subjective sensations to heights.

  1. Effects of interaction imbalance in a strongly repulsive one-dimensional Bose gas

    DEFF Research Database (Denmark)

    Barfknecht, Rafael Emilio; Zinner, Nikolaj Thomas; Foerster, Angela

    2018-01-01

    We calculate the spatial distributions and the dynamics of a few-body two-component strongly interacting Bose gas confined to an effectively one-dimensional trapping potential. We describe the densities for each component in the trap for different interaction and population imbalances. We calcula...

  2. A low-complexity feed-forward I/Q imbalance compensation algorithm

    NARCIS (Netherlands)

    Moseley, N.A.; Slump, Cornelis H.

    2006-01-01

    This paper presents a low-complexity adaptive feed- forward I/Q imbalance compensation algorithm. The feed-forward so- lution has guaranteed stability. Due to its blind nature the algorithm is easily incorporated into an existing receiver design. The algorithm uses three estimators to obtain the

  3. Charge imbalance waves and time-dependent Ginzburg-Landau theory

    Science.gov (United States)

    Octavio, M.; Skocpol, W. J.

    1981-08-01

    We have numerically solved the generalized time-dependent Ginzburg-Landau equation of Kramer and Watts-Tobin, modified to include the capacitive term of Kadin, Smith, and Skocpol. We obtain oscillatory phase-slip solutions which generate damped waves of charge imbalance that propagate along the one-dimensional superconducting filament.

  4. Money Overhang, Credit Overhang and Financial Imbalances in the Euro Area

    NARCIS (Netherlands)

    Kool, C.J.M.; de Regt, E.; van Veen, T.

    2014-01-01

    This paper focusses on the relation between external imbalances and domestic money and credit growth in the euro area. We compute money and credit overhang both for the euro area as a whole and for individual member countries. Our results show that both aggregate money and credit overhang have

  5. Reverse knowledge and technology transfer: imbalances caused by cognitive barriers in asymmetric relationships

    NARCIS (Netherlands)

    Millar-Schijf, Carla C.J.M.; Choi, Chong-Ju

    2009-01-01

    An imbalance exists in almost any type of knowledge and technology transfer due to the information asymmetry of the relationship. However, this is especially the case for reverse technology and knowledge transfer which is epitomised for us by "transfers from an MNC's subsidiary to its headquarters".

  6. Effort reward imbalance is associated with vagal withdrawal in Danish public sector employees

    DEFF Research Database (Denmark)

    Eller, Nanna Hurwitz; Blønd, Morten; Nielsen, Martin

    2011-01-01

    The current study analyzed the relationship between psychosocial work environment assessed by the Effort Reward Imbalance Model (ERI-model) and heart rate variability (HRV) measured at baseline and again, two years later, as this relationship is scarcely covered by the literature....

  7. Socio-Cultural Imbalances in AIED Research: Investigations, Implications and Opportunities

    Science.gov (United States)

    Blanchard, Emmanuel G.

    2015-01-01

    This paper investigates international representations in the Artificial Intelligence in Education (AIED) research field. Its methodological and theoretical groundings are inspired by Arnett (2008) and Henrich et al. (2010a) who addressed the same issue in psychology, and respectively a) discovered massive imbalances in representation in top-tier…

  8. Structural imbalance promotes behavior analogous to aesthetic preference in domestic chicks.

    Directory of Open Access Journals (Sweden)

    Mark A Elliott

    Full Text Available BACKGROUND: Visual images may be judged 'aesthetic' when their positioning appears imbalanced. An apparent imbalance may signify an as yet incomplete action or event requiring more detailed processing. As such it may refer to phylogenetically ancient stimulus-response mechanisms such as those mediating attentional deployment. METHODOLOGY/PRINCIPAL FINDINGS: We studied preferences for structural balance or imbalance in week-old domestic chicks (Gallus gallus, using a conditioning procedure to reinforce pecking at either "aligned" (balanced or "misaligned" (imbalanced training stimuli. A testing phase with novel balanced and imbalanced stimuli established whether chicks would retain their conditioned behavior or revert to chance responding. Whereas those trained on aligned stimuli were equally likely to choose aligned or misaligned stimuli, chicks trained on misaligned stimuli maintained the trained preference. CONCLUSIONS/SIGNIFICANCE: Our results are consistent with the idea that the coding of structural imbalance is primary and even overrides classical conditioning. Generalized to the humans, these results suggest aesthetic judgments based upon structural imbalance may be based on evolutionarily ancient mechanisms, which are shared by different vertebrate species.

  9. The impact of effort-reward imbalance and learning motivation on teachers' sickness absence.

    Science.gov (United States)

    Derycke, Hanne; Vlerick, Peter; Van de Ven, Bart; Rots, Isabel; Clays, Els

    2013-02-01

    The aim of this study was to analyse the impact of the effort-reward imbalance and learning motivation on sickness absence duration and sickness absence frequency among beginning teachers in Flanders (Belgium). A total of 603 teachers, who recently graduated, participated in this study. Effort-reward imbalance and learning motivation were assessed by means of self-administered questionnaires. Prospective data of registered sickness absence during 12 months follow-up were collected. Multivariate logistic regression analyses were performed. An imbalance between high efforts and low rewards (extrinsic hypothesis) was associated with longer sickness absence duration and more frequent absences. A low level of learning motivation (intrinsic hypothesis) was not associated with longer sickness absence duration but was significantly positively associated with sickness absence frequency. No significant results were obtained for the interaction hypothesis between imbalance and learning motivation. Further research is needed to deepen our understanding of the impact of psychosocial work conditions and personal resources on both sickness absence duration and frequency. Specifically, attention could be given to optimizing or reducing efforts spent at work, increasing rewards and stimulating learning motivation to influence sickness absence. Copyright © 2012 John Wiley & Sons, Ltd.

  10. Storage battery operation technique of photovoltaic system to prevent the imbalance of state of charge

    Science.gov (United States)

    Kobayashi, Hirotake; Takigawa, Kiyoshi; Takeda, Yukihiro

    For the large scale storage battery system of a MW class photovoltaic system, simulation analyses were conducted to prevent the imbalance of state of charge. Effects of the charge and discharge I-V characteristics dispersion of individual storage battery on the dispersion of state of charge were elucidated through these analyses. Furthermore, a proper operation method to prevent the imbalance of state of charge was investigated. In the internal resistance and the electromotive voltage which determines the charge and discharge I-V characteristics, when the dispersion is found in the electromotive voltage in particular, the dispersion of state of charge gets larger. The electromotive voltage of storage battery depends on the specific gravity of electrolyte. Consequently, in order to prevent the imbalance of state of charge, it is important to control the specific gravity. For operating the system effectively preventing the imbalance of state of charge, the specific gravity should be controlled within (+ or -) 0.3 percent of approximate mean value.

  11. Evaluation of electrolyte imbalance among tuberculosis patients receiving treatments in Southwestern Nigeria

    Directory of Open Access Journals (Sweden)

    Adebimpe Wasiu Olalekan

    2015-09-01

    Conclusion: Hyponatraemia, hyperkalaemia, and hypochloremia characterized some of the electrolyte imbalance among TB patients receiving treatments. The raised level of bicarbonate may be attributed to overcorrection of respiratory acidosis often found in patients with tuberculosis. Monitoring electrolytes is therefore an important component of TB management.

  12. Burnout among psychosocial oncologists : an application and extension of the effort-reward imbalance model

    NARCIS (Netherlands)

    Rasmussen, Victoria; Turnell, Adrienne; Butow, Phyllis; Juraskova, Ilona; Kirsten, Laura; Wiener, Lori; Patenaude, Andrea; Hoekstra-Weebers, Josette; Grassi, Luigi

    ObjectivesBurnout is a significant problem among healthcare professionals working within the oncology setting. This study aimed to investigate predictors of emotional exhaustion (EE) and depersonalisation (DP) in psychosocial oncologists, through the application of the effort-reward imbalance (ERI)

  13. Allelic imbalance in the diagnosis of benign, atypical and malignant Spitz tumours.

    NARCIS (Netherlands)

    Dijk, M.C.R.F. van; Rombout, P.D.M.; Mooi, W.J.; Molengraft, F.J. van de; Krieken, J.H.J.M. van; Ruiter, D.J.; Ligtenberg, M.J.L.

    2002-01-01

    To test the diagnostic usefulness of allelic imbalance (AI) analysis based on routinely paraffin-embedded tissue, a series of 55 benign Spitz naevi, Spitz tumours with uncertain malignant potential, and malignant Spitzoid melanomas was investigated. Laser microdissection was used to ensure

  14. Relationship between effort-reward imbalance and hair cortisol concentration in female kindergarten teachers

    NARCIS (Netherlands)

    Qi, Xingliang; Zhang, Jing; Liu, Yapeng; Ji, Shuang; Chen, Zheng; Sluiter, Judith K.; Deng, Huihua

    2014-01-01

    The present study aims to investigate the relationship between effort-reward imbalance and hair cortisol concentration among teachers to examine whether hair cortisol can be a biomarker of chronic work stress. Hair samples were collected from 39 female teachers from three kindergartens. Cortisol was

  15. Cognitive vulnerability and implicit emotional processing : imbalance in frontolimbic brain areas?

    NARCIS (Netherlands)

    Groenewold, Nynke A.; Roest, Annelieke M.; Renken, Remco J.; Opmeer, Esther M.; Veltman, Dick J.; van der Wee, Nic J. A.; de Jonge, Peter; Aleman, Andre; Harmer, Catherine J.

    It has been proposed that the neural basis for cognitive vulnerability to depression involves an imbalance in frontolimbic activity during the processing of cues with a negative affective value. Although the question is central to cognitive theory, whether this association is amplified by diagnosis

  16. Born energy, acid-base equilibrium, structure and interactions of end-grafted weak polyelectrolyte layers

    Science.gov (United States)

    Nap, R. J.; Tagliazucchi, M.; Szleifer, I.

    2014-01-01

    This work addresses the effect of the Born self-energy contribution in the modeling of the structural and thermodynamical properties of weak polyelectrolytes confined to planar and curved surfaces. The theoretical framework is based on a theory that explicitly includes the conformations, size, shape, and charge distribution of all molecular species and considers the acid-base equilibrium of the weak polyelectrolyte. Namely, the degree of charge in the polymers is not imposed but it is a local varying property that results from the minimization of the total free energy. Inclusion of the dielectric properties of the polyelectrolyte is important as the environment of a polymer layer is very different from that in the adjacent aqueous solution. The main effect of the Born energy contribution on the molecular organization of an end-grafted weak polyacid layer is uncharging the weak acid (or basic) groups and consequently decreasing the concentration of mobile ions within the layer. The magnitude of the effect increases with polymer density and, in the case of the average degree of charge, it is qualitatively equivalent to a small shift in the equilibrium constant for the acid-base equilibrium of the weak polyelectrolyte monomers. The degree of charge is established by the competition between electrostatic interactions, the polymer conformational entropy, the excluded volume interactions, the translational entropy of the counterions and the acid-base chemical equilibrium. Consideration of the Born energy introduces an additional energetic penalty to the presence of charged groups in the polyelectrolyte layer, whose effect is mitigated by down-regulating the amount of charge, i.e., by shifting the local-acid base equilibrium towards its uncharged state. Shifting of the local acid-base equilibrium and its effect on the properties of the polyelectrolyte layer, without considering the Born energy, have been theoretically predicted previously. Account of the Born energy leads

  17. Born energy, acid-base equilibrium, structure and interactions of end-grafted weak polyelectrolyte layers.

    Science.gov (United States)

    Nap, R J; Tagliazucchi, M; Szleifer, I

    2014-01-14

    This work addresses the effect of the Born self-energy contribution in the modeling of the structural and thermodynamical properties of weak polyelectrolytes confined to planar and curved surfaces. The theoretical framework is based on a theory that explicitly includes the conformations, size, shape, and charge distribution of all molecular species and considers the acid-base equilibrium of the weak polyelectrolyte. Namely, the degree of charge in the polymers is not imposed but it is a local varying property that results from the minimization of the total free energy. Inclusion of the dielectric properties of the polyelectrolyte is important as the environment of a polymer layer is very different from that in the adjacent aqueous solution. The main effect of the Born energy contribution on the molecular organization of an end-grafted weak polyacid layer is uncharging the weak acid (or basic) groups and consequently decreasing the concentration of mobile ions within the layer. The magnitude of the effect increases with polymer density and, in the case of the average degree of charge, it is qualitatively equivalent to a small shift in the equilibrium constant for the acid-base equilibrium of the weak polyelectrolyte monomers. The degree of charge is established by the competition between electrostatic interactions, the polymer conformational entropy, the excluded volume interactions, the translational entropy of the counterions and the acid-base chemical equilibrium. Consideration of the Born energy introduces an additional energetic penalty to the presence of charged groups in the polyelectrolyte layer, whose effect is mitigated by down-regulating the amount of charge, i.e., by shifting the local-acid base equilibrium towards its uncharged state. Shifting of the local acid-base equilibrium and its effect on the properties of the polyelectrolyte layer, without considering the Born energy, have been theoretically predicted previously. Account of the Born energy leads

  18. Imbalance of Ecosystems and the Modified Newton's 3 Laws of Change

    Science.gov (United States)

    Lin, H.

    2013-12-01

    Sustainability calls for the unity of human knowledge that bridges the present "two cultures" gulf between the sciences and the humanities, and the transition from the age of machine to the age of the environment quests for harmony with nature (so-called eco-civilization). Ecosystems are fundamentally different from machines, where individual components contain complex organisms instead of identical nonliving entities. Because of heterogeneity, diversity, self-organization, and openness, imbalances abound in nature. These are reflected in entropy increase over time (S > 0) and gradient persistence over space (F > 0). In this paper, three modified Newton's laws of change for ecosystems are suggested, and examples of imbalances from landscape-soil-water-ecosystem-climate will be illustrated. ● Newton's 1st law of motion: ∑F=0 → dv/dt=0. i.e., if net force acting on an object is zero, then the object's velocity remains unchanged. Modified Newton's 1st law of change (imbalance #1): ∑F>0 → dv/dt≥0. i.e., unavoidable forcing exists in nature (∑F>0), thus change always happens; however, with inertia/resistance in some systems or minimum threshold needed to change, dv/dt≥0. ● Newton's 2nd law of motion: ∑F=ma. i.e., acceleration is inversely proportional to body mass. Modified Newton's 2nd law of change (imbalance #2): ∑F≠ma. i.e., either 1) it is hard to make change because of resilience, self-adjustment, nonlinearity of interactions-feedbacks in living systems (∑F≥ma), or 2) there is possible threshold behavior or sudden collapse of a system (∑Fchange (imbalance #3): ∑F(a,b)≠-∑F(b,a). i.e., to every action, there is an opposite but not necessarily equal reaction (because of energy dissipation and/or self-organization, among other factors).

  19. General characteristics of patients with electrolyte imbalance admitted to emergency department.

    Science.gov (United States)

    Balcı, Arif Kadri; Koksal, Ozlem; Kose, Ataman; Armagan, Erol; Ozdemir, Fatma; Inal, Taylan; Oner, Nuran

    2013-01-01

    Fluid and electrolyte balance is a key concept to understand for maintaining homeostasis, and for a successful treatment of many metabolic disorders. There are various regulating mechanisms for the equilibrium of electrolytes in organisms. Disorders of these mechanisms result in electrolyte imbalances that may be life-threatening clinical conditions. In this study we defined the electrolyte imbalance characteristics of patients admitted to our emergency department. This study was conducted in the Emergency Department (ED) of Uludag University Faculty of Medicine, and included 996 patients over 18 years of age. All patients had electrolyte imbalance, with various etiologies other than traumatic origin. Demographic and clinical parameters were collected after obtaining informed consent from the patients. The ethical committee of the university approved this study. The mean age of the patients was 59.28±16.79, and 55% of the patients were male. The common symptoms of the patients were dyspnea (14.7%), fever (13.7%), and systemic deterioration (11.9%); but the most and least frequent electrolyte imbalances were hyponatremia and hypermagnesemia, respectively. Most frequent findings in physical examination were confusion (14%), edema (10%) and rales (9%); and most frequent pathological findings in ECG were tachycardia in 24%, and atrial fibrillation in 7% of the patients. Most frequent comorbidity was malignancy (39%). Most frequent diagnoses in the patients were sepsis (11%), pneumonia (9%), and acute renal failure (7%). Electrolyte imbalances are of particular importance in the treatment of ED patients. Therefore, ED physicians must be acknowledged of their fluid-electrolyte balance dynamics and general characteristics.

  20. Analysis of the flow imbalance in the KSTAR PF cryo-circuit

    Energy Technology Data Exchange (ETDEWEB)

    Lee, Hyun-Jung, E-mail: yaeban@nfri.re.kr; Park, Dong-Seong; Kwag, Sang-Woo; Joo, Jae-Jun; Moon, Kyung-Mo; Kim, Nam-Won; Lee, Young-Joo; Park, Young-Min; Yang, Hyung-Lyeol

    2015-12-15

    Highlights: • Investigate of flow imbalance trend for the KSTAR PF superconducting magnet. • Flow imbalance is compared with individual magnet test and integration magnet test. • Intensifying of flow imbalance is proven from the flow monitoring in the KSTAR PF circuit. • Flow behavior is analyzed during magnet charging in the circulator circuit. • Variation of magnet outlet temperature is analyzed due to flow imbalance. - Abstract: The KSTAR PF cryo-circuit is a quasi-closed circulation system in which more than 370 g/s of supercritical helium (SHe) is circulated using a SHe circulator. The heated helium from superconducting magnet is cooled through sub cooler (4.3 K). The circulator is operated at 4.5 K and 6.5 bar, and the pressure drop of the circuit is kept at 2 bar in order to maintain the supercritical state and circulator stability. The circuit is connected with helium refrigerator system, distribution system, and supercritical magnet system. It has a hundred branches to supply supercritical helium to the poloidal field superconducting magnet. The branch was designed to optimize the operation conditions and they are grouped for one cryogenic valve has the same length within the cardinal principle of the optimization. Five cryogenic valves are installed to control the mass flow rate, and seven orifice mass flow meters, differential pressure gauges and temperature sensors were installed in front of the magnet in the distribution because upper magnet and lower magnet is symmetric theoretically. The cryogenic pipe line was manufactured with elevation about 10 m between upper magnet and lower magnet. The inlet and outlet helium feed-through were installed at the coil inside in case of KSTAR PF1–PF5 upper magnet and lower magnet. The flow imbalance is caused by void fraction and it could be changed due to manufacturing process even if it has the same length of cooling channel. This creates an imbalance among cooling channels and temperatures are

  1. Co-polarization channel imbalance determination by the use of bare soil

    Science.gov (United States)

    Shi, Lei; Yang, Jie; Li, Pingxiang

    2014-09-01

    This paper describes a novel technique which determines the co-polarization channel imbalance by the use of natural bare soil, instead of a trihedral corner reflector (CR). In polarimetric synthetic aperture radar (PolSAR) remote sensing, the polarimetric calibration (PolCAL) is the key technique in quantitative earth parameter measurement. In general, the current PolCAL process can be separated into two parts. The first part tries to estimate the crosstalk and the cross-polarization (x-pol) channel imbalance components by the reflection symmetry and the reciprocity properties, without a CR. Then, at least one trihedral CR is required to determine the co-polarization (co-pol) channel imbalance; however, it is not always possible to deploy a CR in difficult terrain such as desert. In this paper, we utilize bare soil as a stable reference target, and four common natural constraints of bare soil are evaluated to determine the co-pol channel imbalance, without the use of a CR. It should be mentioned that we do not propose to replace the CR by a natural target, but we utilize the natural target to enhance the PolCAL accuracy when a CR is missing. The four constraints are: (1) the consistency of the polarimetric orientation angle (CPOA) between the PolSAR POA and the digital elevation model (DEM) derived POA; (2) the unitary zero POA (UZPOA) of a flat ground surface; (3) the zero helix (ZHEX) component of the ground surface; and (4) the unitary version of the previous zero helix (UZHEX). In the theoretical part of this paper, we demonstrate that the forth constraint is the most suitable in different scenes. We then propose a multi-scale algorithm to further improve the robustness of the co-pol channel imbalance determination. In the experimental part, we apply our new methods to simulated airborne SAR (AIRSAR) and real uninhabited aerial vehicle SAR (UAVSAR) data. Without the use of any CR, the recovered results show that the estimated amplitude and phase error of the co

  2. KINEMATIC VARIABLES AND BLOOD ACID-BASE STATUS IN THE ANALYSIS OF COLLEGIATE SWIMMERS’ ANAEROBIC CAPACITY

    Directory of Open Access Journals (Sweden)

    Grzegorz Bielec

    2013-06-01

    Full Text Available Short duration repeated maximal efforts are often used in swimming training to improve lactate tolerance, which gives swimmers the ability to maintain a high work rate for a longer period of time. The aim of the study was to examine the kinematics of swimming and its relation to the changes in blood acid-base status and potassium level. Seven collegiate swimmers, with at least 6 years of training experience, volunteered to participate in the study. The test consisted of 8 x 25 m front crawl performed with maximum effort. The rest period between repetitions was set to five seconds. Blood samples were taken from the fingertip at rest, after warm-up and in the 3rd minute after completion of the test. The swimming was recorded with a video recorder, for later analysis of time, velocity and technique (stroke index. Based on the swimming velocity results, the obtained curve can be divided into rapid decrease of velocity and relatively stable velocities. The breaking point of repetition in swimming velocity was assumed as the swimming velocity threshold and it was highly correlated with the decrease of the blood acid-base status (pH r=0.82, BE r=0.87, HCO3- r=0.76; p<0.05 in all cases. There was no correlation between stroke index or fatigue index and blood acid-base status. Analysis of the swimming speed in the 8 x 25 m test seems to be helpful in evaluation of lactate tolerance (anaerobic capacity in collegiate swimmers.

  3. Stewart analysis of apparently normal acid-base state in the critically ill.

    Science.gov (United States)

    Moviat, Miriam; van den Boogaard, Mark; Intven, Femke; van der Voort, Peter; van der Hoeven, Hans; Pickkers, Peter

    2013-12-01

    This study aimed to describe Stewart parameters in critically ill patients with an apparently normal acid-base state and to determine the incidence of mixed metabolic acid-base disorders in these patients. We conducted a prospective, observational multicenter study of 312 consecutive Dutch intensive care unit patients with normal pH (7.35 ≤ pH ≤ 7.45) on days 3 to 5. Apparent (SIDa) and effective strong ion difference (SIDe) and strong ion gap (SIG) were calculated from 3 consecutive arterial blood samples. Multivariate linear regression analysis was performed to analyze factors potentially associated with levels of SIDa and SIG. A total of 137 patients (44%) were identified with an apparently normal acid-base state (normal pH and -2 SIDa values were 36.6 ± 3.6 mEq/L, resulting from hyperchloremia (109 ± 4.6 mEq/L, sodium-chloride difference 30.0 ± 3.6 mEq/L); SIDe values were 33.5 ± 2.3 mEq/L, resulting from hypoalbuminemia (24.0 ± 6.2 g/L); and SIG values were 3.1 ± 3.1 mEq/L. During admission, base excess increased secondary to a decrease in SIG levels and, subsequently, an increase in SIDa levels. Levels of SIDa were associated with positive cation load, chloride load, and admission SIDa (multivariate r(2) = 0.40, P SIDa (caused by hyperchloremia) and high SIG combined with the alkalinizing effect of hypoalbuminemia. © 2013.

  4. A computational study of ultrafast acid dissociation and acid-base neutralization reactions. I. The model.

    Science.gov (United States)

    Maurer, Patrick; Thomas, Vibin; Rivard, Ugo; Iftimie, Radu

    2010-07-28

    Ultrafast, time-resolved investigations of acid-base neutralization reactions have recently been performed using systems containing the photoacid 8-hydroxypyrene-1,3,6-trisulfonic acid trisodium salt (HPTS) and various Bronsted bases. Two conflicting neutralization mechanisms have been formulated by Mohammed et al. [Science 310, 83 (2005)] and Siwick et al. [J. Am. Chem. Soc. 129, 13412 (2007)] for the same acid-base system. Herein an ab initio molecular dynamics based computational model is formulated, which is able to investigate the validity of the proposed mechanisms in the general context of ground-state acid-base neutralization reactions. Our approach consists of using 2,4,6-tricyanophenol (exp. pKa congruent with 1) as a model for excited-state HPTS( *) (pKa congruent with 1.4) and carboxylate ions for the accepting base. We employ our recently proposed dipole-field/quantum mechanics (QM) treatment [P. Maurer and R. Iftimie, J. Chem. Phys. 132, 074112 (2010)] of the proton donor and acceptor molecules. This approach allows one to tune the free energy of neutralization to any desired value as well as model initial nonequilibrium hydration effects caused by a sudden increase in acidity, making it possible to achieve a more realistic comparison with experimental data than could be obtained via a full-QM treatment of the entire system. It is demonstrated that the dipole-field/QM model reproduces correctly key properties of the 2,4,6-tricyanophenol acid molecule including gas-phase proton dissociation energies and dipole moments, and condensed-phase hydration structure and pKa values.

  5. Food composition and acid-base balance: alimentary alkali depletion and acid load in herbivores.

    Science.gov (United States)

    Kiwull-Schöne, Heidrun; Kiwull, Peter; Manz, Friedrich; Kalhoff, Hermann

    2008-02-01

    Alkali-enriched diets are recommended for humans to diminish the net acid load of their usual diet. In contrast, herbivores have to deal with a high dietary alkali impact on acid-base balance. Here we explore the role of nutritional alkali in experimentally induced chronic metabolic acidosis. Data were collected from healthy male adult rabbits kept in metabolism cages to obtain 24-h urine and arterial blood samples. Randomized groups consumed rabbit diets ad libitum, providing sufficient energy but variable alkali load. One subgroup (n = 10) received high-alkali food and approximately 15 mEq/kg ammonium chloride (NH4Cl) with its drinking water for 5 d. Another group (n = 14) was fed low-alkali food for 5 d and given approximately 4 mEq/kg NH4Cl daily for the last 2 d. The wide range of alimentary acid-base load was significantly reflected by renal base excretion, but normal acid-base conditions were maintained in the arterial blood. In rabbits fed a high-alkali diet, the excreted alkaline urine (pH(u) > 8.0) typically contained a large amount of precipitated carbonate, whereas in rabbits fed a low-alkali diet, both pH(u) and precipitate decreased considerably. During high-alkali feeding, application of NH4Cl likewise decreased pH(u), but arterial pH was still maintained with no indication of metabolic acidosis. During low-alkali feeding, a comparably small amount of added NH4Cl further lowered pH(u) and was accompanied by a significant systemic metabolic acidosis. We conclude that exhausted renal base-saving function by dietary alkali depletion is a prerequisite for growing susceptibility to NH4Cl-induced chronic metabolic acidosis in the herbivore rabbit.

  6. Comparison of yogurt, soybean, casein, and amino acid-based diets in children with persistent diarrhea.

    Science.gov (United States)

    de Mattos, Angela P; Ribeiro, Tereza C M; Mendes, Patrícia S A; Valois, Sandra S; Mendes, Carlos M C; Ribeiro, Hugo C

    2009-07-01

    Although previous studies have shown successful treatment of persistent diarrhea (PD) with the use of yogurt-based diets, some recent ones speculate the need of special formulas for the nutritional management of PD complicated cases. In the present study, we tested the hypothesis that the consumption of 3 lactose-free diets, with different degrees of complexity, is associated with lower stool output and shorter duration of diarrhea when compared with the use of a yogurt-based one on the nutritional management of PD. A total of 154 male infants, aged between 1 and 30 months, with PD and with or without dehydration, were randomly assigned to 1 of 4 treatment groups. Throughout the study, the patients were placed in a metabolic unit; their body weights and intakes of oral rehydration solution, water, and formula diets, in addition to outputs of stool, urine, and vomit, were measured and recorded at 24-hour intervals. Four different diets were used in this study: diet 1, yogurt-based formula; diet 2, soy-based formula; diet 3, hydrolyzed protein-based formula; and diet 4, amino acid-based formula. Throughout the study, only these formula diets were fed to the children. The data showed that children fed the yogurt-based diet (diet 1) or the amino acid-based diet (diet 4) had a significant reduction in stool output and in the duration of diarrhea. The use of an inexpensive and worldwide-available yogurt-based diet is recommended as the first choice for the nutritional management of mild to moderate PD. For the few complicated PD cases, when available, a more complex amino acid-based diet should be reserved for the nutritional management of these unresponsive and severe presentations. Soy-based or casein-based diets do not offer any specific advantage or benefits and do not seem to have a place in the management of PD.

  7. Effects of intravenous solutions on acid-base equilibrium: from crystalloids to colloids and blood components.

    Science.gov (United States)

    Langer, Thomas; Ferrari, Michele; Zazzeron, Luca; Gattinoni, Luciano; Caironi, Pietro

    2014-01-01

    Intravenous fluid administration is a medical intervention performed worldwide on a daily basis. Nevertheless, only a few physicians are aware of the characteristics of intravenous fluids and their possible effects on plasma acid-base equilibrium. According to Stewart's theory, pH is independently regulated by three variables: partial pressure of carbon dioxide, strong ion difference (SID), and total amount of weak acids (ATOT). When fluids are infused, plasma SID and ATOT tend toward the SID and ATOT of the administered fluid. Depending on their composition, fluids can therefore lower, increase, or leave pH unchanged. As a general rule, crystalloids having a SID greater than plasma bicarbonate concentration (HCO₃-) cause an increase in plasma pH (alkalosis), those having a SID lower than HCO₃- cause a decrease in plasma pH (acidosis), while crystalloids with a SID equal to HCO₃- leave pH unchanged, regardless of the extent of the dilution. Colloids and blood components are composed of a crystalloid solution as solvent, and the abovementioned rules partially hold true also for these fluids. The scenario is however complicated by the possible presence of weak anions (albumin, phosphates and gelatins) and their effect on plasma pH. The present manuscript summarises the characteristics of crystalloids, colloids, buffer solutions and blood components and reviews their effect on acid-base equilibrium. Understanding the composition of intravenous fluids, along with the application of simple physicochemical rules best described by Stewart's approach, are pivotal steps to fully elucidate and predict alterations of plasma acid-base equilibrium induced by fluid therapy.

  8. The effect of thiopental sodium, methoxyflurane and halothane on the acid-base status in sheep.

    Science.gov (United States)

    Edjtehadi, M; Howard, B R

    1978-01-01

    Experiments have been carried out on 20 adult fat-tailed ewes to determine the effects of thiopental sodium, methoxyflurane and halothane on acid-base status of the saliva loss during prolonged surgical anaesthesia. The rate of loss of base in saliva depends on the volume of saliva produced, which fell sharply at the onset of anesthesia with the volatile anaesthesia. Plasma pH and plasma pvCO2 excess were both increased by the volatile anaesthetics but fell sharply during thiopental anaesthesia. Plasma pH and plasma PvCO2 showed no consistent relationship. PMID:688076

  9. Acid-base properties of sorbents based on zirconium(IV) phosphates

    Energy Technology Data Exchange (ETDEWEB)

    Bekrenev, A.V. [Research Center of Environmental Safety, St. Petersburg (Russian Federation); Pyartman, A.K. [St. Petersburg Institute of Technology (Russian Federation)

    1995-11-01

    The objective of this work was to investigate the acid-base properties of materials based on zirconium(IV) phosphate and diphosphate and to calculate the equilibrium constants for corresponding heterogeneous reactions of binary ion exchange, that is, to calculate the characteristics of the ion-exchange properties for use in calculating more complicated ion-exchange equilibria. The objects of investigation were zirconium(IV) hydroxyphosphate (ZHP) and zirconium(IV) diphosphate (ZDP), as well as composite materials based on said compounds and a porous support material.

  10. [Investigation of reference intervals of blood gas and acid-base analysis assays in China].

    Science.gov (United States)

    Zhang, Lu; Wang, Wei; Wang, Zhiguo

    2015-10-01

    To investigate and analyze the upper and lower limits and their sources of reference intervals in blood gas and acid-base analysis assays. The data of reference intervals were collected, which come from the first run of 2014 External Quality Assessment (EQA) program in blood gas and acid-base analysis assays performed by National Center for Clinical Laboratories (NCCL). All the abnormal values and errors were eliminated. Data statistics was performed by SPSS 13.0 and Excel 2007 referring to upper and lower limits of reference intervals and sources of 7 blood gas and acid-base analysis assays, i.e. pH value, partial pressure of carbon dioxide (PCO2), partial pressure of oxygen (PO2), Na+, K+, Ca2+ and Cl-. Values were further grouped based on instrument system and the difference between each group were analyzed. There were 225 laboratories submitting the information on the reference intervals they had been using. The three main sources of reference intervals were National Guide to Clinical Laboratory Procedures [37.07% (400/1 079)], instructions of instrument manufactures [31.23% (337/1 079)] and instructions of reagent manufactures [23.26% (251/1 079)]. Approximately 35.1% (79/225) of the laboratories had validated the reference intervals they used. The difference of upper and lower limits in most assays among 7 laboratories was moderate, both minimum and maximum (i.e. the upper limits of pH value was 7.00-7.45, the lower limits of Na+ was 130.00-156.00 mmol/L), and mean and median (i.e. the upper limits of K+ was 5.04 mmol/L and 5.10 mmol/L, the upper limits of PCO2 was 45.65 mmHg and 45.00 mmHg, 1 mmHg = 0.133 kPa), as well as the difference in P2.5 and P97.5 between each instrument system group. It was shown by Kruskal-Wallis method that the P values of upper and lower limits of all the parameters were lower than 0.001, expecting the lower limits of Na+ with P value 0.029. It was shown by Mann-Whitney that the statistic differences were found among instrument

  11. Management of Acute Kidney Injury and Acid-Base Balance in the Septic Patient.

    Science.gov (United States)

    Weyker, Paul D; Pérez, Xosé L; Liu, Kathleen D

    2016-06-01

    Acute kidney injury (AKI) is an abrupt decrease in kidney function that takes place over hours to days. Sepsis is the leading cause of AKI and portends a particularly high morbidity and mortality, although the severity may vary from a transient rise in serum creatinine to end-stage renal disease. With regard to acid-base management in septic AKI, caution should be used with hyperchloremic crystalloid solutions, and dialysis is often used in the setting of severe acidosis. In the future, biomarkers may help clinicians identify AKI earlier and allow for potential interventions before the development of severe AKI. Copyright © 2016 Elsevier Inc. All rights reserved.

  12. The scaled-charge additive force field for amino acid based ionic liquids

    DEFF Research Database (Denmark)

    Fileti, E. E.; Chaban, V. V.

    2014-01-01

    Ionic liquids (ILs) constitute an emerging research field. New ILs involve more and more organic and inorganic ions. Amino acid based ILs (AAILs) represent a specific interest due to their evolutional connection to proteins. We report a new non-polarizable force field (FF) for the eight AAILs...... comprising 1-ethyl-3-methylimidazolium cation and amino acid anions. The anions were obtained via deprotonation of carboxyl group. Specific cation-anion non-covalent interactions were taken into account by computing electrostatic potential for ion pairs. The van der Waals interactions were adopted from...

  13. Bis[N,N'-diisopropylbenzamidinato(-)]silicon(II): Lewis acid/base reactions with triorganylboranes.

    Science.gov (United States)

    Junold, Konstantin; Baus, Johannes A; Burschka, Christian; Fonseca Guerra, Célia; Bickelhaupt, F Matthias; Tacke, Reinhold

    2014-09-22

    Reaction of the donor-stabilized silylene 1 (which is three-coordinate in the solid state and four-coordinate in solution) with BEt3 and BPh3 leads to the formation of the Lewis acid/base complexes 2 and 3, respectively, which are the first five-coordinate silicon compounds with an SiB bond. These compounds were structurally characterized by crystal structure analyses and by multinuclear NMR spectroscopic studies in the solid state and in solution. Additionally, the bonding situation in 2 and 3 was analyzed by quantum chemical studies. © 2014 WILEY-VCH Verlag GmbH & Co. KGaA, Weinheim.

  14. Acid-Base Pairs in Lewis Acidic Zeolites Promote Direct Aldol Reactions by Soft Enolization.

    Science.gov (United States)

    Lewis, Jennifer D; Van de Vyver, Stijn; Román-Leshkov, Yuriy

    2015-08-17

    Hf-, Sn-, and Zr-Beta zeolites catalyze the cross-aldol condensation of aromatic aldehydes with acetone under mild reaction conditions with near quantitative yields. NMR studies with isotopically labeled molecules confirm that acid-base pairs in the Si-O-M framework ensemble promote soft enolization through α-proton abstraction. The Lewis acidic zeolites maintain activity in the presence of water and, unlike traditional base catalysts, in acidic solutions. © 2015 WILEY-VCH Verlag GmbH & Co. KGaA, Weinheim.

  15. Bicarbonate Concentration, Acid-Base Status, and Mortality in the Health, Aging, and Body Composition Study.

    Science.gov (United States)

    Raphael, Kalani L; Murphy, Rachel A; Shlipak, Michael G; Satterfield, Suzanne; Huston, Hunter K; Sebastian, Anthony; Sellmeyer, Deborah E; Patel, Kushang V; Newman, Anne B; Sarnak, Mark J; Ix, Joachim H; Fried, Linda F

    2016-02-05

    Low serum bicarbonate associates with mortality in CKD. This study investigated the associations of bicarbonate and acid-base status with mortality in healthy older individuals. We analyzed data from the Health, Aging, and Body Composition Study, a prospective study of well functioning black and white adults ages 70-79 years old from 1997. Participants with arterialized venous blood gas measurements (n=2287) were grouped into bicarbonate categories and according to acid-base status. Survival data were collected through February of 2014. Mortality hazard ratios (HRs; 95% confidence intervals [95% CIs]) in the low and high bicarbonate groups compared with the reference group were determined using Cox models adjusted for demographics, eGFR, albuminuria, chronic obstructive pulmonary disease, smoking, and systemic pH. Similarly adjusted Cox models were performed according to acid-base status. The mean age was 76 years, 51% were women, and 38% were black. Mean pH was 7.41, mean bicarbonate was 25.1 mEq/L, 11% had low bicarbonate, and 10% had high bicarbonate. Mean eGFR was 82.1 ml/min per 1.73 m(2), and 12% had CKD. Over a mean follow-up of 10.3 years, 1326 (58%) participants died. Compared with the reference group, the mortality HRs were 1.24 (95% CI, 1.02 to 1.49) in the low bicarbonate and 1.03 (95% CI, 0.84 to 1.26) in the high bicarbonate categories. Compared with the normal acid-base group, the mortality HRs were 1.17 (95% CI, 0.94 to 1.47) for metabolic acidosis, 1.21 (95% CI, 1.01 to 1.46) for respiratory alkalosis, and 1.35 (95% CI, 1.08 to 1.69) for metabolic alkalosis categories. Respiratory acidosis did not associate with mortality. In generally healthy older individuals, low serum bicarbonate associated with higher mortality independent of systemic pH and potential confounders. This association seemed to be present regardless of whether the cause of low bicarbonate was metabolic acidosis or respiratory alkalosis. Metabolic alkalosis also associated with

  16. [Correction of the acid-base balance in the newborn asphyxia. The use of sodium bicarbonate].

    Science.gov (United States)

    Demi, M; Meneghetti, G

    1982-01-01

    The treatment of neonatal respiratory distress associates the improvement of lung ventilation with the correction of acid-base equilibrium (metabolic acidosis). In such a context we have considered 10 newborns with respiratory distress and we monitored pH, PCO2, B.E. and standard bicarbonate in capillary blood at 1, 5, 10, 25 hours after birth. The sodium bicarbonate doses given as a result of the emogasanalisis are above those usually recommended. We then give suggestions on how to use the sodium bicarbonate required to correct the acidosis without the aid of an emogasanaliser in order to avoid the iatrogenic alcalosis danger.

  17. Electrodeposited Fe-Co films prepared from a citric-acid-based plating bath

    OpenAIRE

    Yanai, Takeshi; Uto, H; Shimokawa, Takaya; Nakano, Masaki; Fukunaga, Hirotoshi; Suzuki, K.

    2013-01-01

    Electrodeposited Fe-Co films are commonly prepared in a boric-acid-based bath. In this research, we applied citric acid instead of boric acid for the plating of Fe-Co films because boron in the waste bath is restricted by environmental-protection regulations in Japan. We evaluated the effect of citric acid on the magnetic and structural properties of the films. The saturation magnetization of the Fe-Co films slightly increased while the Fe content in the Fe-Co films decreased with increasing ...

  18. Design, synthesis and structure of new potential electrochemically active boronic acid-based glucose sensors

    DEFF Research Database (Denmark)

    Norrild, Jens Chr.; Søtofte, Inger

    2002-01-01

    In the course of our investigations on new boronic acid based carbohydrate sensors three new boronic acids 3, 7 and 11 containing a ferrocene moiety were synthesised. Their design includes an intramolecular B-N bonding motif in order to facilitate binding at physiological pH. We report...... with structures obtained of 2,4,6-tris[2-(N,N-dimethylaminomethyl)phenyl]boroxin (14) and 2,2-dimethyl-1,3-diyl[2-(N,N-dimethylaminomethyl)phenyl]boronate (15). The structure of 13 shows the existence of intramolecular B-N bonds in the solid phase....

  19. Amino-Acid-Based Polymerizable Surfactants for the Synthesis of Chiral Nanoparticles.

    Science.gov (United States)

    Preiss, Laura C; Wagner, Manfred; Mastai, Yitzhak; Landfester, Katharina; Muñoz-Espí, Rafael

    2016-09-01

    Amino-acid-based chiral surfactants with polymerizable moieties are synthesized, and a versatile approach to prepare particles thereof with a chiral surface functionality is presented. As an example of an application, the synthesized particles are tested for their ability as nucleating agents in the enantioselective crystallization of amino acid conglomerate systems, taking rac-asparagine as a model system. Particles resulting from chiral surfactants with different tail groups are compared and the results demonstrate that only the chiral nanoparticles made of the polymerizable surfactant are able to act efficiently as nucleation agent in enantioselective crystallization. © 2016 WILEY-VCH Verlag GmbH & Co. KGaA, Weinheim.

  20. Determination of fatty acid based lubricity improver in diesel by GC

    Energy Technology Data Exchange (ETDEWEB)

    Chopra, Anju; Singh, Dheer; Ram Kalsi, Wadhawa; Sugumaran, Vatsala; Singh Sarpal, Amarjit; Basu, Biswajit [Indian Oil Corporation Ltd., Haryana (India). Research and Development Centre

    2009-10-15

    GC/FID has been used for the determination of a fatty acid based lubricity improver in diesel fuel. The method makes use of phase transfer catalysis for the enrichment of the lubricity improver from the diesel matrix. The use of phase transfer catalysis for the simultaneous extraction, preconcentration and derivatisation of the fatty acids enables determination of concentrations of 20 mg L{sup -1}. The method has been successfully applied to the analysis of diesel streams from various sources. The effect of the diesel matrix has also been investigated and it does not affect the recovery of the additive. (orig.)

  1. Characterization of Polymer Surfaces by the Use of Different Wetting Theories Regarding Acid-Base Properties

    Directory of Open Access Journals (Sweden)

    Eduard Kraus

    2017-01-01

    Full Text Available The existing wetting methods for the determination of acid-base properties on solid surfaces are discussed. Striving for a better understanding of the adhesive polymer interactions in adhesively joined polymers, the methods of Berger and van Oss-Chaudhury-Good were found as the most suitable methods for the investigation of wetting on solid polymer surfaces. Methods of nonlinear systems by Della Volpe and Siboni were adapted and evaluated on plastic surfaces. In the context of these investigations various data of the surface free energy as well as its components have been identified for a number of polymer surfaces by application of spatial equation solutions.

  2. Interaction of nucleic acid bases with single-walled carbon nanotube

    Science.gov (United States)

    Shukla, M. K.; Dubey, Madan; Zakar, Eugene; Namburu, Raju; Czyznikowska, Zaneta; Leszczynski, Jerzy

    2009-10-01

    Theoretical investigations at the M05-2X DFT level employing the 6-31G(d), 6-31G(d,p), 6-31+G(d,p) and cc-pVDZ basis sets show that all nucleic acid bases (NABs), guanine, adenine, cytosine, thymine and uracil form stable stacking complexes with the zigzag (7,0) single-walled carbon nanotube (SWCNT). The values of the BSSE corrected interaction energy suggested that among the bases guanine forms the most stable complex. The other bases generate complexes of similar stability with the considered SWCNT that are less stable than the guanine-SWCNT dimer.

  3. The Multifunctional Fish Gill: Dominant Site of Gas Exchange, Osmoregulation, Acid-Base Regulation, and Excretion of Nitrogenous Waste

    National Research Council Canada - National Science Library

    David H. Evans; Peter M. Piermarini; Keith P. Choe

    2005-01-01

    The fish gill is a multipurpose organ that, in addition to providing for aquatic gas exchange, plays dominant roles in osmotic and ionic regulation, acid-base regulation, and excretion of nitrogenous wastes...

  4. CFD analysis of temperature imbalance in superheater/reheater region of tangentially coal-fired boiler

    Science.gov (United States)

    Zainudin, A. F.; Hasini, H.; Fadhil, S. S. A.

    2017-10-01

    This paper presents a CFD analysis of the flow, velocity and temperature distribution in a 700 MW tangentially coal-fired boiler operating in Malaysia. The main objective of the analysis is to gain insights on the occurrences in the boiler so as to understand the inherent steam temperature imbalance problem. The results show that the root cause of the problem comes from the residual swirl in the horizontal pass. The deflection of the residual swirl due to the sudden reduction and expansion of the flow cross-sectional area causes velocity deviation between the left and right side of the boiler. This consequently results in flue gas temperature imbalance which has often caused tube leaks in the superheater/reheater region. Therefore, eliminating the residual swirl or restraining it from being diverted might help to alleviate the problem.

  5. Profile and imbalance cost of wind energy in 2012; Profiel- en onbalanskosten van windenergie in 2020

    Energy Technology Data Exchange (ETDEWEB)

    Nieuwenhout, F.D.J.; Lensink, S. [ECN Beleidsstudies, Amsterdam (Netherlands); Brand, A.J. [ECN Wind Energy, Petten (Netherlands)

    2013-03-28

    This paper describes the method to determine the profile and imbalance costs of wind energy under the SDE+ scheme (Renewable Energy Incentive Plus). This method was first applied in the advice on the final correction figures for 2012. For 2012, the sum of profile and imbalance charges is set at 12.4% of the market index. This implies a slight increase with respect to the percentage in previous years (11%) [Dutch] Deze notitie beschrijft de methode om de profiel- en onbalanskosten van windenergie te bepalen in het kader van de SDE+-regeling (Stimuleringsregeling Duurzame Energie Plus). Deze methode is voor het eerst toegepast in het advies over de definitieve correctiebedragen 2012. Voor 2012 is de som van profiel- en onbalanskosten bepaald op 12,4% van de marktindex. Dit impliceert een geringe stijging ten opzichte van het percentage in voorgaande jaren (11%)

  6. [A Case of Rectal Villous Tumor Detected with Heart Failure and Electrolyte Imbalance].

    Science.gov (United States)

    Kondo, Junya; Maeda, Yoshinari; Nagashima, Yukiko; Nishimura, Taku; Morita, Katsuhiko; Setoguchi, Mihoko; Sakata, Kouichiro

    2015-11-01

    A 74-year-old woman presented to our emergency department with a chief complaint of appetite loss, and already diagnosed dehydration and heart failure. After hospitalization, the signs of heart failure were improved with liquid supplementation and electrolyte revision. At admission, computed tomography incidentally detected a rectal tumor. She underwent colonography, which revealed a huge villous tumor in the rectum. Based on the result of the initial biopsy, it was classified as a group 4 tumor, but additional biopsy of specimens obtained from 6 places led to a diagnosis of group 5 tumor. Then, we performed laparoscopic super-low anterior resection and made an ileal stoma. The electrolyte imbalance was improved and did not recur after the operation. In this case, the electrolyte imbalance caused by the huge villous tumor was electrolyte depletion syndrome (EDS).

  7. Analysis and measurement of the electrolyte imbalance in a vanadium redox flow battery

    Science.gov (United States)

    Ngamsai, Kittima; Arpornwichanop, Amornchai

    2015-05-01

    Electrolyte imbalance in vanadium redox flow batteries is an important problem for its long-term operation as it leads to loss of energy. To address this problem, a modified open circuit voltage (OCV) cell is developed by adding a middle half cell between the negative and positive half cells of a conventional OCV cell and used to predict the oxidation state of vanadium in the electrolyte solution from the measured voltage in each side of the electrolyte (positive and negative). The correlation between the oxidation state of vanadium and cell voltage is explained by a basic electrochemical principle and the Nernst equation. The experimental results show that at different oxidation states of vanadium, the predicted OCV agrees reasonably with the experimental data. In addition, the effect of the state of charge (SOC) and electrolyte imbalance on the energy capacity of a cell is discussed.

  8. Blind estimation of carrier frequency offset, I/Q imbalance and DC offset for OFDM systems

    Science.gov (United States)

    Liu, Tao; Li, Hanzhang

    2012-12-01

    Sensitivity to carrier frequency offset (CFO) is one of the biggest drawbacks of orthogonal frequency division multiplexing (OFDM) system. A lot of CFO estimation algorithms had been studied for compensation of CFO in OFDM system. However, with the adoption of direct-conversion architecture (DCA), which introduces additional impairments such as dc offset (DCO) and in-phase/quadrature (I/Q) imbalance in OFDM system, the established CFO estimation algorithms suffer from performance degradation. In our previous study, we developed a blind CFO, I/Q imbalance and DCO estimation algorithm for OFDM systems with DCA. In this article, we propose an alternative algorithm with reduced computation complexity and better accuracy. Performance of the proposed algorithm is demonstrated by simulations.

  9. Effort-Reward Imbalance at Work and Incident Coronary Heart Disease

    DEFF Research Database (Denmark)

    Dragano, Nico; Siegrist, Johannes; Nyberg, Solja T

    2017-01-01

    BACKGROUND: Epidemiologic evidence for work stress as a risk factor for coronary heart disease is mostly based on a single measure of stressful work known as job strain, a combination of high demands and low job control. We examined whether a complementary stress measure that assesses an imbalance...... between efforts spent at work and rewards received predicted coronary heart disease. METHODS: This multicohort study (the "IPD-Work" consortium) was based on harmonized individual-level data from 11 European prospective cohort studies. Stressful work in 90,164 men and women without coronary heart disease...... at baseline was assessed by validated effort-reward imbalance and job strain questionnaires. We defined incident coronary heart disease as the first nonfatal myocardial infarction or coronary death. Study-specific estimates were pooled by random effects meta-analysis. RESULTS: At baseline, 31.7% of study...

  10. The impact of labour market imbalances on regional disparities in the post-crisis context

    Directory of Open Access Journals (Sweden)

    Gina Cristina DIMIAN

    2012-09-01

    Full Text Available The paper aims to examine how existing imbalances in the labour market influence regions’ future development and to formulate a series of recommendations that will allow that catching up process to be done in an sustainable manner.Basically, the objective refers to the integration of the development and restructuring strategy of the labour market policy to strengthen regional competitive advantage.Our intentions is to stress the fact that between labour market imbalances and regional disparities exists a bi-univocal relationship, both manifested in a complex external environment, dominated by variable factors and uncertainty.To achieve paper’ objectives scientific methods like: descriptive statistics, correlation analysis and aggregate indexes are applied.The main results are focused on formulating a set of scientifically based recommendations that can be used to conceive strategies whose overall objective is the reduction of economic disparities existing in certain regions through training and proper human resources development.

  11. Effort-Reward Imbalance at Work and Incident Coronary Heart Disease

    DEFF Research Database (Denmark)

    Dragano, Nico; Siegrist, Johannes; Nyberg, Solja T.

    2017-01-01

    Background: Epidemiologic evidence for work stress as a risk factor for coronary heart disease is mostly based on a single measure of stressful work known as job strain, a combination of high demands and low job control. We examined whether a complementary stress measure that assesses an imbalance...... between efforts spent at work and rewards received predicted coronary heart disease. Methods: This multicohort study (the “IPD-Work” consortium) was based on harmonized individual-level data from 11 European prospective cohort studies. Stressful work in 90,164 men and women without coronary heart disease...... at baseline was assessed by validated effort–reward imbalance and job strain questionnaires. We defined incident coronary heart disease as the first nonfatal myocardial infarction or coronary death. Study-specific estimates were pooled by random effects meta-analysis. Results: At baseline, 31.7% of study...

  12. Compensation for HPA nonlinearity and I/Q imbalance in MIMO beamforming systems

    KAUST Repository

    Qi, Jian

    2010-10-01

    In this paper, we investigate the effects of high-power amplifier (HPA) nonlinearity and in-phase and quadrature-phase (I/Q) imbalance on the performance of multiple-input multiple-output (MIMO) transmit beamforming (TB) systems. Specifically, we propose a compensation method for HPA nonlinearity and I/Q imbalance together in MIMO TB systems. The performance of the MIMO TB system under study is evaluated in terms of the average symbol error probability (SEP) and system capacity, considering transmission over uncorrelated frequency-flat Rayleigh fading channels. Numerical results are provided and show the effects of several system parameters, such as the HPA parameters, image-leakage ratio, numbers of transmit and receive antennas, length of pilot symbols, and modulation order of phase-shift keying (PSK), on performance. © 2010 IEEE.

  13. Constraining the Global Ocean Heat Content Through Assimilation of CERES-Derived TOA Energy Imbalance Estimates

    Science.gov (United States)

    Storto, Andrea; Yang, Chunxue; Masina, Simona

    2017-10-01

    The Earth's energy imbalance (EEI) is stored in the oceans for the most part. Thus, estimates of its variability can be ingested in ocean retrospective analyses to constrain the global ocean heat budget. Here we propose a scheme to assimilate top of the atmosphere global radiation imbalance estimates from Clouds and the Earth's Radiant Energy System (CERES) in a coarse-resolution variational ocean reanalysis system (2000-2014). The methodology proves able to shape the heat content tendencies according to the EEI estimates, without compromising the reanalysis accuracy. Spurious variability and underestimation (overestimation) present in experiments with in situ (no) data assimilation disappear when EEI data are assimilated. The warming hiatus present without the assimilation of EEI data is mitigated, inducing ocean warming at depths below 1,500 m and slightly larger in the Southern Hemisphere, in accordance with recent studies. Furthermore, the methodology may be applied to Earth System reanalyses and climate simulations to realistically constrain the global energy budget.

  14. Correlation between arterial blood gas analysis and peripheral blood gas analysis in acid-base unbalance state

    OpenAIRE

    Lee Kim, Hyun; Ho Ryu, Hyun

    2012-01-01

    Acid-base unbalance is most common problem in severe ill patient, especially in condition of abnormal renal function state. Acid-base unbalances are respiratory acidosis, respiratory alkalosis, metabolic acidosis, and metabolic alkalosis. Metabolic acidosis is frequently appeared in clinical state. Arterial blood gas analysis is considered as a basic test to the intensive care unit patient and emergency state. Recently some researches were done, comparing with arterial blood gas analysis and ...

  15. Steering neuronal growth cones by shifting the imbalance between exocytosis and endocytosis.

    Science.gov (United States)

    Tojima, Takuro; Itofusa, Rurika; Kamiguchi, Hiroyuki

    2014-05-21

    Extracellular molecular cues guide migrating growth cones along specific routes during development of axon tracts. Such processes rely on asymmetric elevation of cytosolic Ca(2+) concentrations across the growth cone that mediates its attractive or repulsive turning toward or away from the side with Ca(2+) elevation, respectively. Downstream of these Ca(2+) signals, localized activation of membrane trafficking steers the growth cone bidirectionally, with endocytosis driving repulsion and exocytosis causing attraction. However, it remains unclear how Ca(2+) can differentially regulate these opposite membrane-trafficking events. Here, we show that growth cone turning depends on localized imbalance between exocytosis and endocytosis and identify Ca(2+)-dependent signaling pathways mediating such imbalance. In embryonic chicken dorsal root ganglion neurons, repulsive Ca(2+) signals promote clathrin-mediated endocytosis through a 90 kDa splice variant of phosphatidylinositol-4-phosphate 5-kinase type-1γ (PIPKIγ90). In contrast, attractive Ca(2+) signals facilitate exocytosis but suppress endocytosis via Ca(2+)/calmodulin-dependent protein kinase II (CaMKII) and cyclin-dependent kinase 5 (Cdk5) that can inactivate PIPKIγ90. Blocking CaMKII or Cdk5 leads to balanced activation of both exocytosis and endocytosis that causes straight growth cone migration even in the presence of guidance signals, whereas experimentally perturbing the balance restores the growth cone's turning response. Remarkably, the direction of this resumed turning depends on relative activities of exocytosis and endocytosis, but not on the type of guidance signals. Our results suggest that navigating growth cones can be redirected by shifting the imbalance between exocytosis and endocytosis, highlighting the importance of membrane-trafficking imbalance for axon guidance and, possibly, for polarized cell migration in general. Copyright © 2014 the authors 0270-6474/14/347165-14$15.00/0.

  16. REER Imbalances and Macroeconomic Adjustments in the Proposed West African Monetary Union

    OpenAIRE

    Asongu, Simplice A

    2013-01-01

    With the spectre of the Euro crisis hunting embryonic monetary unions, we use a dynamic model of a small open economy to analyze REERs imbalances and examine whether the movements in the aggregate real exchange rates are consistent with the underlying macroeconomic fundamentals in the proposed West African Monetary Union (WAMU). Using both country-oriented and WAMU panel-based specifications, we show that the long-run behavior of the REERs can be explained by fluctuations in the terms of trad...

  17. Subfunctionalization reduces the fitness cost of gene duplication in humans by buffering dosage imbalances.

    Science.gov (United States)

    Fernández, Ariel; Tzeng, Yun-Huei; Hsu, Sze-Bi

    2011-12-14

    Driven essentially by random genetic drift, subfunctionalization has been identified as a possible non-adaptive mechanism for the retention of duplicate genes in small-population species, where widespread deleterious mutations are likely to cause complementary loss of subfunctions across gene copies. Through subfunctionalization, duplicates become indispensable to maintain the functional requirements of the ancestral locus. Yet, gene duplication produces a dosage imbalance in the encoded proteins and thus, as investigated in this paper, subfunctionalization must be subject to the selective forces arising from the fitness bottleneck introduced by the duplication event. We show that, while arising from random drift, subfunctionalization must be inescapably subject to selective forces, since the diversification of expression patterns across paralogs mitigates duplication-related dosage imbalances in the concentrations of encoded proteins. Dosage imbalance effects become paramount when proteins rely on obligatory associations to maintain their structural integrity, and are expected to be weaker when protein complexation is ephemeral or adventitious. To establish the buffering effect of subfunctionalization on selection pressure, we determine the packing quality of encoded proteins, an established indicator of dosage sensitivity, and correlate this parameter with the extent of paralog segregation in humans, using species with larger population -and more efficient selection- as controls. Recognizing the role of subfunctionalization as a dosage-imbalance buffer in gene duplication events enabled us to reconcile its mechanistic nonadaptive origin with its adaptive role as an enabler of the evolution of genetic redundancy. This constructive role was established in this paper by proving the following assertion: If subfunctionalization is indeed adaptive, its effect on paralog segregation should scale with the dosage sensitivity of the duplicated genes. Thus

  18. Molecular Cytogenetics: Genomic Imbalances in Colorectal Cancer and their Clinical Impact

    Directory of Open Access Journals (Sweden)

    Marian Grade

    2006-01-01

    Full Text Available Chromosomal aberrations play a dominant role in colorectal carcinogenesis. The application of fluorescence in situ hybridization (FISH based techniques such as comparative genomic hybridization (CGH and spectral karyotyping (SKY revealed that colorectal carcinomas are characterized by a specific pattern of chromosomal imbalances which sequentially accumulate during cancer progression. This review aims to summarize molecular cytogenetic studies, provides a background on the functional relevance of chromosomal aberrations for colorectal cancer progression and discusses their potential clinical impact.

  19. Labour Market Reforms and Current Account Imbalances: Beggar-thy-neighbour policies in a currency union?

    OpenAIRE

    Baas, Timo; Belke, Ansgar

    2014-01-01

    Member countries of the Economic and Monetary Union (EMU) initiated wide-ranging labour market reforms in the last decade. This process is ongoing as countries that are faced with serious labour market imbalances perceive reforms as the fastest way to restore competitiveness within a currency union. This fosters fears among observers about a beggar-thy-neighbour policy that leaves non-reforming countries with a loss in competitiveness and an increase in foreign debt. Using a two-country, two-...

  20. Relaxation of the chiral imbalance in dense matter of a neutron star

    Directory of Open Access Journals (Sweden)

    Dvornikov Maxim

    2016-01-01

    Full Text Available Using the quantum field theory methods, we calculate the helicity flip of an electron scattering off protons in dense matter of a neutron star. The influence of the electroweak interaction between electrons and background nucleons on the helicity flip is examined. We also derive the kinetic equation for the chiral imbalance. The derived kinetic equation is compared with the results obtained by other authors.

  1. Seasonal Imbalances in Natural Gas Imports in Major Northeast Asian Countries: Variations, Reasons, Outlooks and Countermeasures

    OpenAIRE

    Zhaoyang Kong; Xiucheng Dong; Zhongbing Zhou

    2015-01-01

    The seasonal imbalances and price premiums of natural gas imports (NGIs) seriously affect the sustainability of these imports in major Northeast Asian countries, namely, China, Japan, and South Korea. Research on NGI seasonality might provide new insights that may help solve these issues. Unfortunately, little research has been conducted on this topic. Therefore, this paper examined the seasonalities of Chinese, Japanese, and South Korean NGIs using the X-12-ARIMA model to analyze monthly and...

  2. Subfunctionalization reduces the fitness cost of gene duplication in humans by buffering dosage imbalances

    Directory of Open Access Journals (Sweden)

    Fernández Ariel

    2011-12-01

    Full Text Available Abstract Background Driven essentially by random genetic drift, subfunctionalization has been identified as a possible non-adaptive mechanism for the retention of duplicate genes in small-population species, where widespread deleterious mutations are likely to cause complementary loss of subfunctions across gene copies. Through subfunctionalization, duplicates become indispensable to maintain the functional requirements of the ancestral locus. Yet, gene duplication produces a dosage imbalance in the encoded proteins and thus, as investigated in this paper, subfunctionalization must be subject to the selective forces arising from the fitness bottleneck introduced by the duplication event. Results We show that, while arising from random drift, subfunctionalization must be inescapably subject to selective forces, since the diversification of expression patterns across paralogs mitigates duplication-related dosage imbalances in the concentrations of encoded proteins. Dosage imbalance effects become paramount when proteins rely on obligatory associations to maintain their structural integrity, and are expected to be weaker when protein complexation is ephemeral or adventitious. To establish the buffering effect of subfunctionalization on selection pressure, we determine the packing quality of encoded proteins, an established indicator of dosage sensitivity, and correlate this parameter with the extent of paralog segregation in humans, using species with larger population -and more efficient selection- as controls. Conclusions Recognizing the role of subfunctionalization as a dosage-imbalance buffer in gene duplication events enabled us to reconcile its mechanistic nonadaptive origin with its adaptive role as an enabler of the evolution of genetic redundancy. This constructive role was established in this paper by proving the following assertion: If subfunctionalization is indeed adaptive, its effect on paralog segregation should scale with the dosage

  3. Serious Gender Imbalance in Medical and Dentistry Majors: How to Prevent a Crisis

    OpenAIRE

    SMJ Mortazavi; Rashidi Nejad HR

    2005-01-01

    Background and Purpose: Decreased males’ motivation for entering universities has caused a low male/female ratio in different university majors. In 2005-2006 academic year, enrollment of female students in Rafsanjan University of Medical Sciences reached 83.14%. This tremendous gender imbalance may lead to the development of a mono-sex system for health service providers and will.affect the social health system. As females constitute the majority of students.in all medical sciences majors, in...

  4. Microarray comparative genomic hybridization detection of chromosomal imbalances in uterine cervix carcinoma

    OpenAIRE

    García José; Pérez Carlos; López Ricardo; Lazos Minerva; González José; Hernández Dulce; Vázquez-Ortiz Guelaguetza; Piña Patricia; Arreola Hugo; Petersen Iver; Baudis Michael; Hidalgo Alfredo; Vázquez Karla; Alatorre Brenda; Salcedo Mauricio

    2005-01-01

    Abstract Background Chromosomal Comparative Genomic Hybridization (CGH) has been applied to all stages of cervical carcinoma progression, defining a specific pattern of chromosomal imbalances in this tumor. However, given its limited spatial resolution, chromosomal CGH has offered only general information regarding the possible genetic targets of DNA copy number changes. Methods In order to further define specific DNA copy number changes in cervical cancer, we analyzed 20 cervical samples (3 ...

  5. Inflammation Activation Contributes to Adipokine Imbalance in Patients with Acute Coronary Syndrome.

    Science.gov (United States)

    Li, Rong; Chen, Lu-zhu; Zhao, Shui-ping; Huang, Xian-sheng

    2016-01-01

    Inflammation can be activated as a defensive response by the attack of acute coronary syndrome (ACS) for ischemic tissue injury. The aim of the present study was to investigate the impact of ACS-activated inflammation on adipokine imbalance and the effects of statins on the crosstalk between inflammation and adipokine imbalance during ACS. In this study, 586 subjects were categorized into: (1) control group; (2) SA (stable angina) group; and (3) ACS group. Circulating levels of hs-CRP, adiponectin and resistin were measured by ELISA. Furthermore, forty C57BL/6 mice were randomized into: sham, AMI, low-statin (atorvastatin, 2 mg/kg/day) and high-statin (atorvastatin, 20 mg/kg/day) group. After 3 weeks, AMI models were established by surgical coronary artery ligation. Circulating levels and adipose expressions of adiponectin and resistin were assessed in animals. Besides, we investigate the effects of atorvastatin on ox-LDL-induced adipokine imbalance in vitro. As a result, we found that ACS patients had higher hs-CRP and resistin levels and lower adiponectin levels. Our correlation analysis demonstrated hs-CRP concentrations were positively correlated with resistin but negatively with adiponectin levels in humans. Our animal findings indicated higher circulating hs-CRP and resistin levels and lower adiponectin levels in AMI mice. Atorvastatin pre-treatment dose-dependently decreased hs-CRP and resistin levels but increased adiponectin levels in mice. The consistent findings were observed about the adipose expressions of resistin and adiponectin in mice. In study in vitro, ox-LDL increased cellular resistin expressions and otherwise for adiponectin expressions, which dose-dependently reversed by the addition of atorvastatin. Therefore, our study indicates that the ACS attack activates inflammation leading to adipokine imbalance that can be ameliorated by anti-inflammation of atorvastatin.

  6. Opportunity integrated assessment facilitating critical thinking and science process skills measurement on acid base matter

    Science.gov (United States)

    Sari, Anggi Ristiyana Puspita; Suyanta, LFX, Endang Widjajanti; Rohaeti, Eli

    2017-05-01

    Recognizing the importance of the development of critical thinking and science process skills, the instrument should give attention to the characteristics of chemistry. Therefore, constructing an accurate instrument for measuring those skills is important. However, the integrated instrument assessment is limited in number. The purpose of this study is to validate an integrated assessment instrument for measuring students' critical thinking and science process skills on acid base matter. The development model of the test instrument adapted McIntire model. The sample consisted of 392 second grade high school students in the academic year of 2015/2016 in Yogyakarta. Exploratory Factor Analysis (EFA) was conducted to explore construct validity, whereas content validity was substantiated by Aiken's formula. The result shows that the KMO test is 0.714 which indicates sufficient items for each factor and the Bartlett test is significant (a significance value of less than 0.05). Furthermore, content validity coefficient which is based on 8 experts is obtained at 0.85. The findings support the integrated assessment instrument to measure critical thinking and science process skills on acid base matter.

  7. Activities of Heterogeneous Acid-Base Catalysts for Fragrances Synthesis: A Review

    Directory of Open Access Journals (Sweden)

    Hartati Hartati

    2013-06-01

    Full Text Available This paper reviews various types of heterogeneous acid-base catalysts for fragrances preparation. Catalytic activities of various types of heterogeneous acid and base catalysts in fragrances preparation, i.e. non-zeolitic, zeolitic, and mesoporous molecular sieves have been reported. Generally, heterogeneous acid catalysts are commonly used in fragrance synthesis as compared to heterogeneous base catalysts. Heteropoly acids and hydrotalcites type catalysts are widely used as heterogeneous acid and base catalysts, respectively. © 2013 BCREC UNDIP. All rights reservedReceived: 20th January 2013; Revised: 31st March 2013; Accepted: 1st April 2013[How to Cite: Hartati, H., Santoso, M., Triwahyono, S., Prasetyoko, D. (2013. Activities of Heterogeneous Acid-Base Catalysts for Fragrances Synthesis: A Review. Bulletin of Chemical Reaction Engineering & Catalysis, 8 (1: 14-33. (doi:10.9767/bcrec.8.1.4394.14-33][Permalink/DOI: http://dx.doi.org/10.9767/bcrec.8.1.4394.14-33] | View in  |

  8. Enhanced dispersion of boron nitride nanosheets in aqueous media by using bile acid-based surfactants

    Science.gov (United States)

    Chae, Ari; Park, Soo-Jin; Min, Byunggak; In, Insik

    2018-01-01

    Facile noncovalent surface functionalization of hydroxylated boron nitride nanosheet (BNNS-OH) was attempted through the sonication-assisted exfoliation of h-BN in aqueous media in the presence of bile acid-based surfactants such as sodium cholic acid (SC) or sodium deoxycholic acid (SDC), resulting in SC- or SDC-BNNS-OH dispersion with high up to 2 mg ml‑1 and enhanced dispersion stability due to the increased negative zeta potential. While prepared SC-BNNS-OH revealed multi-layered BNNS structures, the large lateral sizes of hundreds nanometers and clear h-BN lattice structures are very promising for the preparation and application of water-processable BNNS-based nanomaterials. It is regarded that noncovalent functionalization of BNNS-OH based on σ-π interaction between with σ-rich bile acid-based amphiphiles and π-rich BNNS is very effective to formulate multi-functional BNNS-based nanomaterials or hybrids that can be utilized in various applications where both the pristine properties of BNNS and the extra functions are simultaneously required.

  9. Critical care nephrology: management of acid-base disorders with CRRT.

    Science.gov (United States)

    Cerdá, Jorge; Tolwani, Ashita J; Warnock, David G

    2012-07-01

    Normal acid-base homeostasis is severely challenged in the intensive care setting. In this review, we address acid-base disturbances, with a special focus on the use of continuous (rather than intermittent) extracorporeal technologies in critical ill patients with acute kidney injury. We consider hypercapnic acidosis and lactic acidosis as examples in which continuous modalities may have different roles and indications than the traditional intermittent approaches to renal replacement therapy. Hypercapnic acidosis develops as a consequence of alveolar hypoventilation. In this condition, correction of pH above 7.2 is not currently recommended, and may even abrogate the beneficial effects of hypercapnic acidosis on overall outcomes. Extracorporeal technologies support lung protection while maintaining overall patient homeostasis. Similarly, in lactic acidosis, current evidence does not support bicarbonate infusions to correct acidosis. The management of lactic acidosis should correct the underlying causative disturbances. Most often, lactic acidosis is a biomarker denoting unfavorable outcomes, rather than an intrinsic pathogenetic mechanism. Extracorporeal procedures may assist in the removal of pathogenic drugs or toxins, as well as partially correcting acidemia. Whether or not these approaches will permit normalization of systemic pH, and the impact of these approaches on patient outcomes, needs to be addressed with prospective controlled trials.

  10. A Prebiotic Chemistry Experiment on the Adsorption of Nucleic Acids Bases onto a Natural Zeolite.

    Science.gov (United States)

    Anizelli, Pedro R; Baú, João Paulo T; Gomes, Frederico P; da Costa, Antonio Carlos S; Carneiro, Cristine E A; Zaia, Cássia Thaïs B V; Zaia, Dimas A M

    2015-09-01

    There are currently few mechanisms that can explain how nucleic acid bases were synthesized, concentrated from dilute solutions, and/or protected against degradation by UV radiation or hydrolysis on the prebiotic Earth. A natural zeolite exhibited the potential to adsorb adenine, cytosine, thymine, and uracil over a range of pH, with greater adsorption of adenine and cytosine at acidic pH. Adsorption of all nucleic acid bases was decreased in artificial seawater compared to water, likely due to cation complexation. Furthermore, adsorption of adenine appeared to protect natural zeolite from thermal degradation. The C=O groups from thymine, cytosine and uracil appeared to assist the dissolution of the mineral while the NH2 group from adenine had no effect. As shown by FT-IR spectroscopy, adenine interacted with a natural zeolite through the NH2 group, and cytosine through the C=O group. A pseudo-second-order model best described the kinetics of adenine adsorption, which occurred faster in artificial seawaters.

  11. The glmS Ribozyme Cofactor is a General Acid-Base Catalyst

    Science.gov (United States)

    Viladoms, Julia; Fedor, Martha J.

    2012-01-01

    The glmS ribozyme is the first natural self-cleaving ribozyme known to require a cofactor. The D-glucosamine-6-phosphate (GlcN6P) cofactor has been proposed to serve as a general acid, but its role in the catalytic mechanism has not been established conclusively. We surveyed GlcN6P-like molecules for their ability to support self-cleavage of the glmS ribozyme and found a strong correlation between the pH dependence of the cleavage reaction and the intrinsic acidity of the cofactors. For cofactors with low binding affinities the contribution to rate enhancement was proportional to their intrinsic acidity. This linear free-energy relationship between cofactor efficiency and acid dissociation constants is consistent with a mechanism in which the cofactors participate directly in the reaction as general acid-base catalysts. A high value for the Brønsted coefficient (β ~ 0.7) indicates that a significant amount of proton transfer has already occurred in the transition state. The glmS ribozyme is the first self-cleaving RNA to use an exogenous acid-base catalyst. PMID:23113700

  12. Flavor, relative palatability and components of cow's milk hydrolysed formulas and amino acid-based formula.

    Science.gov (United States)

    Miraglia Del Giudice, Michele; D'Auria, Enza; Peroni, Diego; Palazzo, Samuele; Radaelli, Giovanni; Comberiati, Pasquale; Galdo, Francesca; Maiello, Nunzia; Riva, Enrica

    2015-06-03

    Both extensively hydrolysed formulas (eHF) and amino acid-based formula (AAFs) have been demonstrated effective for the treatment of CMA. However, in clinical practice, parents complain that hydrolysates are rejected by children due to their bad taste. Flavor of hydrolysed formulas has been poorly investigated although it affects the acceptance of milk over all the other attributes. The aim of the present study was to understand the factors underlying the unpleasant flavor of hydrolysed 25 formulas and amino acid-based formula. One hundred and fifty trained panelists performed a randomized-double-blind test with different milks. The smell, texture, taste and aftertaste of each formula were evaluated on a scale ranging from -2 (worst) to 2 (best). Formulas showed significant difference, as compared to cow's milk, in smell, texture, taste and aftertaste. Overall, whey eHFs were judged of better palatability than casein eHF and the AAFs (p milks' flavor and nutrient profile of hydrolysed formulas are warranted.

  13. Pulmonary histopathologic findings, acid-base status, and absorption of colostral immunoglobulins in newborn calves.

    Science.gov (United States)

    López, A; Löfstedt, J; Bildfell, R; Horney, B; Burton, S

    1994-09-01

    A study was conducted to investigate whether aspiration of amniotic fluid is associated with a deleterious effect on absorption of colostral immunoglobulins or on blood gas and acid-base values of healthy newborn calves. Fourteen calves purchased from commercial sources were transported to a research facility immediately after birth and fed colostrum with known concentrations of immunoglobulins. Blood samples for gas analyses were collected within 5 hours of birth, 24 hours later, and prior to euthanasia. Between 3 and 5 days of age, calves were euthanatized by an overdose of barbiturates. Eleven calves had evidence of bronchoaspiration of amniotic fluid, as determined by presence of meconium, squamous epithelium, or keratin in histologic sections of fixed lung or by cytologic analysis of bronchoalveolar lavage fluid. Blood gas tensions and pH were within reference ranges in 11 of 14 calves. Aspiration of amniotic fluid could not be linked to any specific changes in blood gas tensions, acid-base status, or absorption of colostral immunoglobulins. Presence of keratin and meconium in the lungs often was accompanied by mild exudative alveolitis and focal atelectasis. It was concluded that aspiration of small amounts of amniotic fluid with or without meconium is common in calves and is not associated with hypoxemia, respiratory acidosis, or failure of passive transfer.

  14. Changes in acid-base balance during electrolytic ablation in an ex vivo perfused liver model.

    Science.gov (United States)

    Gravante, Gianpiero; Ong, Seok Ling; Metcalfe, Matthew S; Sorge, Roberto; Fox, Andrew J; Lloyd, David M; Maddern, Guy J; Dennison, Ashley R

    2012-11-01

    Electrolytic ablation (EA) destroys tissues through extreme pH changes in the local microenvironment. An ex vivo perfused liver model was used to assess the systemic effects of EA on the acid-base balance without the influence of compensatory organs (lungs and kidneys). Eleven pigs were perfused extracorporeally at 39°C with autologous blood; 4 also underwent EA after 1 hour of reperfusion. Arterial blood samples were obtained hourly. pH and CO(2) levels did not change throughout the experiments. A significant increase of HCO(3)-, anion gap, base excess, and lactate was present after the third hour. No differences were observed between EA experiments and controls. EA does not alter the acid-base balance even when the confounding influence of compensatory organs is removed. Such findings should be considered when planning ablations in patients with renal failure or respiratory diseases in which EA could avoid undesirable metabolic changes. Copyright © 2012 Elsevier Inc. All rights reserved.

  15. The effects of Energised Greens™ upon blood acid-base balance during resting conditions

    Directory of Open Access Journals (Sweden)

    Mitchell Nigel

    2011-10-01

    Full Text Available Abstract Background The consumption of fresh fruit & vegetable in concentrate form (FVC have recently become an alternative approach to combating excessive renal acid loads often associated with Western Diets. Additionally, these FVC's have been purported to induce metabolic alkalosis, which perhaps may enhance the blood buffering capacity of an individual. Therefore, the aim of this preliminary study was to profile the acid-base response after ingestion of an acute dose of fruit and vegetable extract (Energised Greens™ (EG, Nottingham, UK and compare it to a standard, low dose (0.1 g·kg-1 of sodium bicarbonate (NaHCO3. Findings As part of a randomized, cross over design participants consumed 750 mL of water with either 9 g of EG (manufacturer recommendations, 0.1 g·kg-1 of NaHCO3 or a placebo (plain flour in opaque encapsulated pills following an overnight fast. Capillary samples were obtained and analyzed every 15 min for a period of 120 min following ingestion. Significant interactions (p 3-, BE. Interactions indicated significant elevation in blood alkalosis for only the NaHCO3 condition when compared to both placebo and EG from 15 to 120 minutes. Conclusions Despite previous findings of elevated blood pH following acute mineral supplementation, manufacturer recommended doses of EG do not induce any significant changes in acid-base regulation in resting males.

  16. AMINO ACID-BASED FERTILIZER AS AN ALTERNATIVE TO CALDA VIÇOSA IN ORGANIC AGRICULTURE

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    Diego Fontebasso Pelizari Pinto

    2017-10-01

    Full Text Available The aim of this study was to propose a mixture of micronutrients with amino acid-based foliar fertilizer as an alternative to calda viçosa for application in organic agriculture. The study was conducted in two simultaneous trials in an experimental field in Ipeúna, SP, Brazil. The test plant was carioca type dry edible bean cv. Pérola. The treatments in trial 1 were: Control 1 = water; FA = JK® amino acid-based foliar fertilizer; and FA+Mi = FA + CuSO4 + ZnSO4 + MnSO4 + H3BO3. In trial 2, the FA treatment was substituted by calda viçosa (CVi. The treatments were through spray application three times. Dry edible bean leaves were sampled for determination of macronutrient and micronutrient concentrations. Platings of the application rates used in the treatments were performed in the laboratory in a mixture with Bacillus thuringiensis and with Beauveria bassiana to compare the degree of compatibility by means of colony forming units (CFU. The FA+Mi and CVi treatments raised the concentrations of Zn, Cu, and Mn in the leaves. The FA+Mi was compatible, the FA was a stimulant, and the CVi was noxious to B. bassiana and to B. thuringiensis when integrated in the spray mixture.

  17. An Exact Method to Determine the Conductivity of Aqueous Solutions in Acid-Base Titrations

    Directory of Open Access Journals (Sweden)

    Norma Rodríguez-Laguna

    2015-01-01

    Full Text Available Several works in the literature show that it is possible to establish the analytic equations to estimate the volume V of a strong base or a strong acid (Vb and Va, resp. being added to a solution of a substance or a mix of substances during an acid-base titration, as well as the equations to estimate the first derivative of the titration plot dpH/dV, and algebraic expressions to determine the buffer β capacity with dilution βdil. This treatment allows establishing the conditions of thermodynamic equilibria for all species within a system containing a mix of species from one or from various polyacid systems. The present work shows that it is possible to determine exactly the electric conductivity of aqueous solutions for these Brønsted acid-base titrations, because the functional relation between this property and the composition of the system in equilibrium is well known; this is achieved using the equivalent conductivity λi values of each of the ions present in a given system. The model employed for the present work confirms the experimental outcomes with the H2SO4, B(OH3, CH3COOH, and H3PO4 aqueous solutions’ titration.

  18. Coefficient of Friction Between Carboxymethylated Hyaluronic Acid-Based Polymer Films and the Ocular Surface.

    Science.gov (United States)

    Colter, Jourdan; Wirostko, Barbara; Coats, Brittany

    2017-12-01

    Hyaluronic acid-based polymer films are emerging as drug-delivery vehicles for local and continuous drug administration to the eye. The highly lubricating hyaluronic acid increases comfort, but displaces films from the eye, reducing drug exposure and efficacy. Previous studies have shown that careful control of the surface interaction of the film with the eye is critical for improved retention. In this study, the frictional interaction of a carboxymethylated, hyaluronic acid-based polymer (CMHA-S) with and without methylcellulose was quantified against ovine and human sclera at three axial loads (0.3, 0.5, and 0.7 N) and four sliding velocities (0.3, 1.0, 10, and 30 mm/s). Static coefficients of friction significantly increased with rate (P < 0.003), ranging between 0.18 ± 0.08 and 0.46 ± 0.13 for 0.3 to 30 mm/s, respectively. Friction became more rate-dependent when methylcellulose was added to CMHA-S. Kinetic coefficient of friction was not affected by rate, and averaged 0.15 ± 0.1. Methylcellulose increased CMHA-S static and kinetic friction by 60% and 80%, respectively, but was also prone to wear during testing. These data suggest that methylcellulose can be used to create a friction differential on the film, but a potentially increased degradation rate with the methylcellulose must be considered in the design.

  19. Ammonia production from amino acid-based biomass-like sources by engineered Escherichia coli.

    Science.gov (United States)

    Mikami, Yosuke; Yoneda, Hisanari; Tatsukami, Yohei; Aoki, Wataru; Ueda, Mitsuyoshi

    2017-12-01

    The demand for ammonia is expected to increase in the future because of its importance in agriculture, industry, and hydrogen transportation. Although the Haber-Bosch process is known as an effective way to produce ammonia, the process is energy-intensive. Thus, an environmentally friendly ammonia production process is desired. In this study, we aimed to produce ammonia from amino acids and amino acid-based biomass-like resources by modifying the metabolism of Escherichia coli. By engineering metabolic flux to promote ammonia production using the overexpression of the ketoisovalerate decarboxylase gene (kivd), derived from Lactococcus lactis, ammonia production from amino acids was 351 mg/L (36.6% yield). Furthermore, we deleted the glnA gene, responsible for ammonia assimilation. Using yeast extract as the sole source of carbon and nitrogen, the resultant strain produced 458 mg/L of ammonia (47.8% yield) from an amino acid-based biomass-like material. The ammonia production yields obtained are the highest reported to date. This study suggests that it will be possible to produce ammonia from waste biomass in an environmentally friendly process.

  20. Acid-Base Polymeric Foams for the Adsorption of Micro-oil Droplets from Industrial Effluents.

    Science.gov (United States)

    Cherukupally, Pavani; Acosta, Edgar J; Hinestroza, Juan P; Bilton, Amy M; Park, Chul B

    2017-08-01

    Separation of toxic organic pollutants from industrial effluents is a great environmental challenge. Herein, an acid-base engineered foam is employed for separation of micro-oil droplets from an aqueous solution. In acidic or basic environments, acid-base polymers acquire surface charge due to protonation or dissociation of surface active functional groups. This property is invoked to adsorb crude oil microdroplets from water using polyester polyurethane (PESPU) foam. The physicochemical surface properties of the foam were characterized using X-ray photoelectron spectroscopy, inverse gas chromatography, electrokinetic analysis, and micro-computed tomography. Using the surface charge of the foam and oil droplets, the solution pH (5.6) for maximum separation efficacy was predicted. This optimal pH was verified through underwater wetting behavior and adsorption experiments. The droplet adsorption onto the foam was governed by physisorption, and the driving forces were attributed to electrostatic attraction and Lifshitz-van der Waals forces. The foam was regenerated and reused multiple times by simple compression. The lowest trace oil content in the retentate was 3.6 mg L-1, and all oil droplets larger than 140 nm were removed. This work lays the foundation for the development of a new class of engineered foam adsorbents with the potential to revolutionize water treatment technologies.

  1. American Society of Nephrology quiz and questionnaire 2014: acid-base and electrolyte disorders.

    Science.gov (United States)

    Rosner, Mitchell H; Perazella, Mark A; Choi, Michael J

    2015-03-06

    The Nephrology Quiz and Questionnaire remains an extremely popular session for attendees of the Annual Kidney Week Meeting of the American Society of Nephrology. Once again, in 2014 the conference hall was overflowing with audience members and eager quiz participants. Topics covered by the expert discussants included electrolyte and acid-base disorders, glomerular disease, ESRD/dialysis, and transplantation. Complex cases from each of these categories along with single-best-answer questions were prepared and submitted by the panel of experts. Before the meeting, program directors of United States nephrology training programs and nephrology fellows answered the questions using an Internet-based questionnaire. During the live session, members of the audience tested their knowledge and judgment on a series of case-oriented questions prepared and discussed by the experts. They compared their answers in real time using audience response devices with the answers of the nephrology fellows and training program directors. The correct and incorrect answers were then discussed after the audience responses and the results of the questionnaire were displayed. As always, the audience, lecturers, and moderators enjoyed this educational session. This article recapitulates the acid-base and electrolyte disorders portion of the session and reproduces its educational value for the readers of the Clinical Journal of the American Society of Nephrology. Enjoy the clinical cases and expert discussions. Copyright © 2015 by the American Society of Nephrology.

  2. Site-specific acid-base properties of pholcodine and related compounds.

    Science.gov (United States)

    Kovács, Z; Hosztafi, S; Noszál, B

    2006-11-01

    The acid-base properties of pholcodine, a cough-depressant agent, and related compounds including metabolites were studied by 1H NMR-pH titrations, and are characterised in terms of macroscopic and microscopic protonation constants. New N-methylated derivatives were also synthesized in order to quantitate site- and nucleus-specific protonation shifts and to unravel microscopic acid-base equilibria. The piperidine nitrogen was found to be 38 and 400 times more basic than its morpholine counterpart in pholcodine and norpholcodine, respectively. The protonation data show that the molecule of pholcodine bears an average of positive charge of 1.07 at physiological pH, preventing it from entering the central nervous system, a plausible reason for its lack of analgesic or addictive properties. The protonation constants of pholcodine and its derivatives are interpreted by comparing with related molecules of pharmaceutical interest. The pH-dependent relative concentrations of the variously protonated forms of pholcodine and morphine are depicted in distribution diagrams.

  3. Modelling of the acid base properties of two thermophilic bacteria at different growth times

    Science.gov (United States)

    Heinrich, Hannah T. M.; Bremer, Phil J.; McQuillan, A. James; Daughney, Christopher J.

    2008-09-01

    Acid-base titrations and electrophoretic mobility measurements were conducted on the thermophilic bacteria Anoxybacillus flavithermus and Geobacillus stearothermophilus at two different growth times corresponding to exponential and stationary/death phase. The data showed significant differences between the two investigated growth times for both bacterial species. In stationary/death phase samples, cells were disrupted and their buffering capacity was lower than that of exponential phase cells. For G. stearothermophilus the electrophoretic mobility profiles changed dramatically. Chemical equilibrium models were developed to simultaneously describe the data from the titrations and the electrophoretic mobility measurements. A simple approach was developed to determine confidence intervals for the overall variance between the model and the experimental data, in order to identify statistically significant changes in model fit and thereby select the simplest model that was able to adequately describe each data set. Exponential phase cells of the investigated thermophiles had a higher total site concentration than the average found for mesophilic bacteria (based on a previously published generalised model for the acid-base behaviour of mesophiles), whereas the opposite was true for cells in stationary/death phase. The results of this study indicate that growth phase is an important parameter that can affect ion binding by bacteria, that growth phase should be considered when developing or employing chemical models for bacteria-bearing systems.

  4. Amino acid-based zwitterionic polymers: antifouling properties and low cytotoxicity.

    Science.gov (United States)

    Li, Wenchen; Liu, Qingsheng; Liu, Lingyun

    2014-01-01

    A group of five amino acid containing zwitterionic vinyl monomers, based on serine, lysine, ornithine, glutamic acid, and aspartic acid, respectively, were proposed and developed for potential antifouling applications. Their polymer brushes were grafted on gold chips by surface-initiated photoiniferter-mediated polymerization. We then compared their performance in resisting protein adsorption from full human serum and plasma. All five polymers can reduce protein adsorption by more than 90% compared to the unmodified gold. The ornithine-based and aspartic acid-based poly(methacrylamide) can most strongly resist protein adsorption from serum and plasma, compared to the other three. The ability of surfaces to suppress bacterial adhesion is another criterion in evaluating antifouling properties of materials. Our results show that the five polymer-grafted surfaces can significantly suppress Escherichia coli K12 adhesion to 99% compared to the bare gold surface. The zwitterionic structure of amino acids, with homogenously distributed and balanced positive and negative charges, is responsible for the outstanding antifouling properties. Considering multiple potential applications (e.g. medical devices and drug delivery) of the antifouling materials, we further systematically evaluated the cytotoxicity of both monomers and polymer nanogels for all five materials at various concentrations. Very low cytotoxicity was observed for all tested amino acid-based monomers and nanogels, which is comparable or even lower than the traditional and some newly developed antifouling materials, which might be related to the biomimetic nature of amino acids.

  5. Impact of Hot Environment on Fluid and Electrolyte Imbalance, Renal Damage, Hemolysis, and Immune Activation Postmarathon

    Directory of Open Access Journals (Sweden)

    Rodrigo Assunção Oliveira

    2017-01-01

    Full Text Available Previous studies have demonstrated the physiological changes induced by exercise exposure in hot environments. We investigated the hematological and oxidative changes and tissue damage induced by marathon race in different thermal conditions. Twenty-six male runners completed the São Paulo International Marathon both in hot environment (HE and in temperate environment (TE. Blood and urine samples were collected 1 day before, immediately after, 1 day after, and 3 days after the marathon to analyze the hematological parameters, electrolytes, markers of tissue damage, and oxidative status. In both environments, the marathon race promotes fluid and electrolyte imbalance, hemolysis, oxidative stress, immune activation, and tissue damage. The marathon runner’s performance was approximately 13.5% lower in HE compared to TE; however, in HE, our results demonstrated more pronounced fluid and electrolyte imbalance, renal damage, hemolysis, and immune activation. Moreover, oxidative stress induced by marathon in HE is presumed to be related to protein/purine oxidation instead of other oxidative sources. Fluid and electrolyte imbalance and protein/purine oxidation may be important factors responsible for hemolysis, renal damage, immune activation, and impaired performance after long-term exercise in HE. Nonetheless, we suggested that the impairment on performance in HE was not associated to the muscle damage and lipoperoxidation.

  6. An imbalance in progenitor cell populations reflects tumour progression in breast cancer primary culture models

    LENUS (Irish Health Repository)

    Donatello, Simona

    2011-04-26

    Abstract Background Many factors influence breast cancer progression, including the ability of progenitor cells to sustain or increase net tumour cell numbers. Our aim was to define whether alterations in putative progenitor populations could predict clinicopathological factors of prognostic importance for cancer progression. Methods Primary cultures were established from human breast tumour and adjacent non-tumour tissue. Putative progenitor cell populations were isolated based on co-expression or concomitant absence of the epithelial and myoepithelial markers EPCAM and CALLA respectively. Results Significant reductions in cellular senescence were observed in tumour versus non-tumour cultures, accompanied by a stepwise increase in proliferation:senescence ratios. A novel correlation between tumour aggressiveness and an imbalance of putative progenitor subpopulations was also observed. Specifically, an increased double-negative (DN) to double-positive (DP) ratio distinguished aggressive tumours of high grade, estrogen receptor-negativity or HER2-positivity. The DN:DP ratio was also higher in malignant MDA-MB-231 cells relative to non-tumourogenic MCF-10A cells. Ultrastructural analysis of the DN subpopulation in an invasive tumour culture revealed enrichment in lipofuscin bodies, markers of ageing or senescent cells. Conclusions Our results suggest that an imbalance in tumour progenitor subpopulations imbalances the functional relationship between proliferation and senescence, creating a microenvironment favouring tumour progression.

  7. Can an energy balance model provide additional constraints on how to close the energy imbalance?

    Science.gov (United States)

    Wohlfahrt, Georg; Widmoser, Peter

    2013-01-01

    Elucidating the causes for the energy imbalance, i.e. the phenomenon that eddy covariance latent and sensible heat fluxes fall short of available energy, is an outstanding problem in micrometeorology. This paper tests the hypothesis that the full energy balance, through incorporation of additional independent measurements which determine the driving forces of and resistances to energy transfer, provides further insights into the causes of the energy imbalance and additional constraints on energy balance closure options. Eddy covariance and auxiliary data from three different biomes were used to test five contrasting closure scenarios. The main result of our study is that except for nighttime, when fluxes were low and noisy, the full energy balance generally did not contain enough information to allow further insights into the causes of the imbalance and to constrain energy balance closure options. Up to four out of the five tested closure scenarios performed similarly and in up to 53% of all cases all of the tested closure scenarios resulted in plausible energy balance values. Our approach may though provide a sensible consistency check for eddy covariance energy flux measurements. PMID:24465072

  8. Genomic imbalances in 5918 malignant epithelial tumors: an explorative meta-analysis of chromosomal CGH data

    Directory of Open Access Journals (Sweden)

    Baudis Michael

    2007-12-01

    Full Text Available Abstract Background Chromosomal abnormalities have been associated with most human malignancies, with gains and losses on some genomic regions associated with particular entities. Methods Of the 15429 cases collected for the Progenetix molecular-cytogenetic database, 5918 malignant epithelial neoplasias analyzed by chromosomal Comparative Genomic Hybridization (CGH were selected for further evaluation. For the 22 clinico-pathological entities with more than 50 cases, summary profiles for genomic imbalances were generated from case specific data and analyzed. Results With large variation in overall genomic instability, recurring genomic gains and losses were prominent. Most entities showed frequent gains involving 8q2, while gains on 20q, 1q, 3q, 5p, 7q and 17q were frequent in different entities. Loss "hot spots" included 3p, 4q, 13q, 17p and 18q among others. Related average imbalance patterns were found for clinically distinct entities, e.g. hepatocellular carcinomas (ca. and ductal breast ca., as well as for histologically related entities (squamous cell ca. of different sites. Conclusion Although considerable case-by-case variation of genomic profiles can be found by CGH in epithelial malignancies, a limited set of variously combined chromosomal imbalances may be typical for carcinogenesis. Focus on the respective regions should aid in target gene detection and pathway deduction.

  9. Structural imbalances as a key factor of unemployment in the Russian labor market

    Directory of Open Access Journals (Sweden)

    I V Trotsuk

    2015-12-01

    Full Text Available In recent years, the problems of the Russian labor market, especially the scale and characteristics of youth unemployment, get very emotional and negative coverage in the scientific and journalistic discourses. The authors seek to show without any emotional evaluations what are the objective macroeconomic causes of the current situation with unemployment, especially youth unemployment. First, the authors identify the main challenges the labor market faces today in terms of the interaction of its key actors (workers, owners of the means of production, educational institutions and various intermediaries, including the state regulating the features of labor recruitment. Second, the article shows the main trends of the last decade that change the structure of employment of the economically active population. Third, the authors name the basic structural imbalances in the Russian labor market, primarily structural and professional imbalance between the demand for labor, the demand for vocational training and offer of educational services, which is quite evident, albeit in different ways, in all spheres of the economy. Fourth, the article describes the specific features of the youth labor market as both affected and contributing to the structural imbalances. Finally, the authors propose a methodology of macroeconomic forecasting that may reduce the problems the Russian society faces in the field of employment.

  10. Mineral imbalances in farm animals and their study and diagnosis with isotopic tracers.

    Science.gov (United States)

    Underwood, E J

    1976-12-01

    Twenty-two mineral elements are known to be essential for animal life. These are calcium, phosphorus, sulphur, potassium, sodium, chlorine, magnesium, iron, iodine, copper, manganese, zinc, cobalt, molybdenum, selenium, chromium, tin, vanadium, fluorine, silicon, nickel and arsenic. Naturally occurring and man-made dietary imbalances of many of these elements and their interactions with other minerals are described and their functions and requirements by farm animals are outlined. The nature and importance of metabolic interactions among the mineral elements are discussed and the important concept stressed that there is no single minimum requirement or safe tolerance of a particular mineral, but a series of such minimum requirements and safe tolerances depending on the extent to which other minerals with which it interacts is present or absent from the diet. Radioactive tracer elements are shown to be of great value in the determination of mineral nutrient availability to the animal and for following mineral metabolic movements in the body. They are also shown to have considerable potential for the diagnosis of mineral imbalances. Various in vivo and in vitro techniques, involving both radioactive and stable tracers developed for the early diagnosis of mineral deficiencies are described and the strengths and weaknesses of such techniques in comparison with standard biochemical tests, are discussed. The need for further critical studies with isotopic tracers in the detection and diagnosis of mineral imbalances is emphasized. The main types of biochemical criteria used in the diagnosis of mineral deficiencies and excesses are given, with appropriate examples of their use.

  11. The immediate effect of kinesiology taping on muscular imbalance for infants with congenital muscular torticollis.

    Science.gov (United States)

    Öhman, Anna M

    2012-07-01

    To investigate the immediate effect of kinesiology taping (KT) on muscular imbalance in the lateral flexors of the neck. A retrospective study. Twenty-eight infants with congenital muscular torticollis and muscular imbalance in the lateral flexors of the neck were chosen consecutively. Data regarding the Muscle Function Scale (MFS) score before and after the first taping session were obtained from the records. A significant decrease in the difference between the MFS scores was found after KT was applied (P < .001). Significantly greater scores were noted on the unaffected side after KT (P = .02) and significantly lower scores were noted on the affected side after KT (P = .003). Multiple regression demonstrated that the MFS score on the unaffected side (P < .001) and use of the muscle-relaxing technique (P = .009) were significantly associated with a decrease in the difference between the MFS scores of the 2 sides. KT has an immediate effect on muscular imbalance in infants with congenital muscular torticollis. Copyright © 2012 American Academy of Physical Medicine and Rehabilitation. Published by Elsevier Inc. All rights reserved.

  12. Socio-economic and environmental aspects of the industry imbalances in the regional economy

    Directory of Open Access Journals (Sweden)

    Dmitriy Valer'evich Eidenzon

    2013-12-01

    Full Text Available The paper presents an analysis of current socio-economic and environmental aspects of the industry imbalances in the regional economy by the example of Ural Federal District and Siberian Federal District. The main aim of it is to identify the actual socio-economic problems in the development of the regional economies. The authors analyze the economic, ecological and social aspects in the development of regional economies by the examples. They investigate the specifics of the correlation between industrial development, ecological problems and health problems of the local population. Particular emphasis is placed on the analysis of correlations between the mortality of the population and industrial pollution of air and water. The analysis has resulted in making proposals for optimization of the regional policy in the field of investments, manufacturing and ecology. The special attention is given to environment-oriented projects. The most practicable way in solving the problem of these regional industry imbalances would be the development of regional diversification programs of the Siberia and the Ural economies. It has to support manufacturing and the largest public-private investment projects for the foundation of enterprises in agriculture, food and other industries. The most prosperous among them is the direction of bioenergy and forest-engineering-oriented businesses. The results of the research can be useful in solving the problem of the industry imbalances in the regional economic policy of the Russian Federation.

  13. The impact of public debt on the twin imbalances in Europe: A threshold model

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    Šuliková Veronika

    2017-01-01

    Full Text Available Recent empirical research rejecting twin deficits in indebted countries and current account imbalances adjustment in Europe led to the idea to test the twin imbalances at different public debt-to-GDP intervals. The analysis covers 14 EU countries over the time period 1995-2012. A panel data threshold model with fixed effects estimates two debt-to-GDP thresholds (40.2% and 96.6%, which determine three debt-to-GDP intervals in the twin relationship. If public debtto-GDP is less than 40.2%, the model determines a negative relationship (twin divergence between budget balance and current account. Twin deficits (surpluses are confirmed exclusively if debt-to-GDP is in the interval between 40.2% and 96.6%. A twin divergence is also confirmed if public debt-to-GDP is more than 96.6% (e.g., as in Greece and Italy. The results confirm that increased indebtedness in European countries contributed to their current account imbalance adjustment.

  14. The Imbalance and Self-Organization in the Earth's Climate System (Invited)

    Science.gov (United States)

    Maslov, L.

    2013-12-01

    The increase in frequency and severity of storms, hurricanes and other atmospheric phenomena indicates a progressive imbalance in all planetary systems. Study of the temperature curve obtained from the Antarctic ice core showed that this data can be considered as a sum of two components: the 'cyclic' component and the 'stochastic' component, representing two different but tightly interconnected processes. The 'cyclic' and the 'stochastic' components represent two different types of self-organization of the Earth's climate system. The self-organization in the 'cyclic' process is a non-linear reaction of the Earth's climate system, as a whole, to the input of solar radiation. The self-organization in the 'stochastic' part is a self-organized nonlinear critical process, taking energy from, and fluctuating around the 'cyclic' part of the temperature variations. As a whole, the Earth's climate can be characterized as a nonlinear, self-organized, dynamic system with two levels of self-organization. This research can shed some light on the global climate imbalance and help us to understand the current trends in global weather and to predict global weather trends in the distant and not so distant future. First of all, global warming, as can be seen in repeated high temperature spikes in temperature cycles, has happened in every past climate cycle. The present interglacial period lasts a little bit longer than previous similar periods. This can be because of additional warming caused by human industrial activity. But, following the 'cyclic' pattern of glacial and interglacial temperature cycles, one can conclude that we are at the very beginning of a gradual cooling period to temperatures below freezing. This process is accompanied by sharp and intense fluctuations of temperature, represented by the 'stochastic' part of global temperature curve. Atmospheric temperature fluctuations are the direct result, and at the same time, a cause of atmospheric imbalance. It is

  15. Imbalance in Groundwater-Surface Water Interactions and its Relationship to the Coastal Zone Hazards

    Science.gov (United States)

    Kontar, Y. A.; Ozorovich, Y. R.; Salokhiddinov, A. T.

    2011-12-01

    We report here some efforts and results in studying the imbalance in groundwater-surface water interactions and processes of groundwater-surface water interactions and groundwater flooding creating hazards in the coastal zones. Hazards, hydrological and geophysical risk analysis related to imbalance in groundwater-surface water interactions and groundwater flooding have been to a large extent under-emphasized for coastal zone applications either due to economical limitations or underestimation of significance of imbalance in groundwater-surface water interactions. This is particularly true for tsunamis creating salt water intrusion to coastal aquifers, even though most tsunami hazard assessments have in the past relied on scenario or deterministic type models, and to increasing mineralization of potable water because of intensive water diversions and also the abundance of highly toxic pollutants (mainly pesticides) in water, air and food, which contribute to the deterioration of the coastal population's health. In the wake of pressing environmental and economic issues, it is of prime importance for the scientific community to shed light onto the great efforts by hydrologists and geophysicists to quantify conceptual uncertainties and to provide quality assurances of potential coastal zone hazard evaluation and prediction under conditions of imbalance in groundwater-surface water interactions. This paper proposes consideration of two case studies which are important and significant for future understanding of a concept of imbalance in groundwater-surface water interactions and development and essential for feasibility studies of hazards in the coastal zone. The territory of the Aral Sea Region in Central Asia is known as an ecological disaster coastal zone. It is now obvious that, in order to provide reasonable living conditions to the coastal zone population, it is first of all necessary to drastically improve the quality of the water dedicated to human needs. Due

  16. Acid-base balance and hydration status following consumption of mineral-based alkaline bottled water

    Directory of Open Access Journals (Sweden)

    Heil Daniel P

    2010-09-01

    Full Text Available Abstract Background The present study sought to determine whether the consumption of a mineral-rich alkalizing (AK bottled water could improve both acid-base balance and hydration status in young healthy adults under free-living conditions. The AK water contains a naturally high mineral content along with Alka-PlexLiquid™, a dissolved supplement that increases the mineral content and gives the water an alkalizing pH of 10.0. Methods Thirty-eight subjects were matched by gender and self-reported physical activity (SRPA, hrs/week and then split into Control (12 women, 7 men; Mean +/- SD: 23 +/- 2 yrs; 7.2 +/- 3.6 hrs/week SRPA and Experimental (13 women, 6 men; 22 +/- 2 yrs; 6.4 +/- 4.0 hrs/week SRPA groups. The Control group consumed non-mineralized placebo bottled water over a 4-week period while the Experimental group consumed the placebo water during the 1st and 4th weeks and the AK water during the middle 2-week treatment period. Fingertip blood and 24-hour urine samples were collected three times each week for subsequent measures of blood and urine osmolality and pH, as well as total urine volume. Dependent variables were analyzed using multivariate repeated measures ANOVA with post-hoc focused on evaluating changes over time within Control and Experimental groups (alpha = 0.05. Results There were no significant changes in any of the dependent variables for the Control group. The Experimental group, however, showed significant increases in both the blood and urine pH (6.23 to 7.07 and 7.52 to 7.69, respectively, a decreased blood and increased urine osmolality, and a decreased urine output (2.51 to 2.05 L/day, all during the second week of the treatment period (P Conclusions Consumption of AK water was associated with improved acid-base balance (i.e., an alkalization of the blood and urine and hydration status when consumed under free-living conditions. In contrast, subjects who consumed the placebo bottled water showed no changes over the

  17. The role of acid-base effects on particle charging in apolar media.

    Science.gov (United States)

    Gacek, Matthew Michael; Berg, John C

    2015-06-01

    The creation and stabilization of electric charge in apolar environments (dielectric constant≈2) have been an area of interest dating back to when an explanation was sought for the occurrence of what are now known as electrokinetic explosions during the pumping of fuels. More recently attention has focused on the charging of suspended particles in such media, underlying such applications as electrophoretic displays (e.g., the Amazon Kindle® reader) and new printing devices (e.g., the HP Indigo® Digital Press). The endeavor has been challenging owing to the complexity of the systems involved and the large number of factors that appear to be important. A number of different, and sometimes conflicting, theories for particle surface charging have been advanced, but most observations obtained in the authors' laboratory, as well as others, appear to be explainable in terms of an acid-base mechanism. Adducts formed between chemical functional groups on the particle surface and monomers of reverse micelle-forming surfactants dissociate, leaving charged groups on the surface, while the counter-charges formed are sequestered in the reverse micelles. For a series of mineral oxides in a given medium with a given surfactant, surface charging (as quantified by the maximum electrophoretic mobility or zeta potential obtained as surfactant concentration is varied) was found to scale linearly with the aqueous PZC (or IEP) values of the oxides. Different surfactants, with the same oxide series, yielded similar behavior, but with different PZC crossover points between negative and positive particle charging, and different slopes of charge vs. PZC. Thus the oxide series could be used as a yardstick to characterize the acid-base properties of the surfactants. This has led directly to the study of other materials, including surface-modified oxides, carbon blacks, pigments (charge transfer complexes), and polymer latices. This review focuses on the acid-base mechanism of particle

  18. Impact of I/Q imbalance on the performance of two-way CSI-assisted AF relaying

    KAUST Repository

    Qi, Jian

    2013-04-01

    In this paper, we investigate half-duplex two-way dual-hop channel state information (CSI)-assisted amplify-and-forward (AF) relaying in the presence of in-phase and quadrature-phase (I/Q) imbalance. A compensation approach for the I/Q imbalance is proposed, which employs the received signals together with their conjugations to detect the desired signal. We also derive the average symbol error probability of the considered half-duplex two-way dual-hop CSI-assisted AF relaying networks with and without compensation for I/Q imbalance in Rayleigh fading channels. Numerical results are provided and show that the proposed compensation method mitigates the impact of I/Q imbalance to a certain extent. © 2013 IEEE.

  19. Analysis and Compensation of Transmitter and Receiver I/Q Imbalances in Space-Time Coded Multiantenna OFDM Systems

    Directory of Open Access Journals (Sweden)

    Zou Yaning

    2008-01-01

    Full Text Available Abstract The combination of orthogonal frequency division multiplexing (OFDM and multiple-input multiple-output (MIMO techniques has been widely considered as the most promising approach for building future wireless transmission systems. The use of multiple antennas poses then big restrictions on the size and cost of individual radio transmitters and receivers, to keep the overall transceiver implementation feasible. This results in various imperfections in the analog radio front ends. One good example is the so-called I/Q imbalance problem related to the amplitude and phase matching of the transceiver I and Q chains. This paper studies the performance of space-time coded (STC multiantenna OFDM systems under I/Q imbalance, covering both the transmitter and the receiver sides of the link. The challenging case of frequency-selective I/Q imbalances is assumed, being an essential ingredient in future wideband wireless systems. As a practical example, the Alamouti space-time coded OFDM system with two transmit and M receive antennas is examined in detail and a closed-form solution for the resulting signal-to-interference ratio (SIR at the detector input due to I/Q imbalance is derived. This offers a valuable analytical tool for assessing the I/Q imbalance effects in any STC-OFDM system, without lengthy data or system simulations. In addition, the impact of I/Q imbalances on the channel estimation in the STC-OFDM context is also analyzed analytically. Furthermore, based on the derived signal models, a practical pilot-based I/Q imbalance compensation scheme is also proposed, being able to jointly mitigate the effects of frequency-selective I/Q imbalances as well as channel estimation errors. The performance of the compensator is analyzed using extensive computer simulations, and it is shown to virtually reach the perfectly matched reference system performance with low pilot overhead.

  20. Analysis and Compensation of Transmitter and Receiver I/Q Imbalances in Space-Time Coded Multiantenna OFDM Systems

    Directory of Open Access Journals (Sweden)

    Yaning Zou

    2007-12-01

    Full Text Available The combination of orthogonal frequency division multiplexing (OFDM and multiple-input multiple-output (MIMO techniques has been widely considered as the most promising approach for building future wireless transmission systems. The use of multiple antennas poses then big restrictions on the size and cost of individual radio transmitters and receivers, to keep the overall transceiver implementation feasible. This results in various imperfections in the analog radio front ends. One good example is the so-called I/Q imbalance problem related to the amplitude and phase matching of the transceiver I and Q chains. This paper studies the performance of space-time coded (STC multiantenna OFDM systems under I/Q imbalance, covering both the transmitter and the receiver sides of the link. The challenging case of frequency-selective I/Q imbalances is assumed, being an essential ingredient in future wideband wireless systems. As a practical example, the Alamouti space-time coded OFDM system with two transmit and M receive antennas is examined in detail and a closed-form solution for the resulting signal-to-interference ratio (SIR at the detector input due to I/Q imbalance is derived. This offers a valuable analytical tool for assessing the I/Q imbalance effects in any STC-OFDM system, without lengthy data or system simulations. In addition, the impact of I/Q imbalances on the channel estimation in the STC-OFDM context is also analyzed analytically. Furthermore, based on the derived signal models, a practical pilot-based I/Q imbalance compensation scheme is also proposed, being able to jointly mitigate the effects of frequency-selective I/Q imbalances as well as channel estimation errors. The performance of the compensator is analyzed using extensive computer simulations, and it is shown to virtually reach the perfectly matched reference system performance with low pilot overhead.

  1. Immunologic, spectrophotometric and nucleic acid based methods for the detection and quantification of airborne pollen.

    Science.gov (United States)

    Rittenour, William R; Hamilton, Robert G; Beezhold, Donald H; Green, Brett J

    2012-09-28

    Microscopic identification of pollen morphological phenotypes has been the traditional method used to identify and quantify pollen collected by air monitoring stations worldwide. Although this method has enabled a semi-standardized approach for the assessment of pollen exposure, limitations including labor intensiveness, required expertise, examiner bias, and the inability to differentiate species, genera, and in some cases families have limited data derived from the these stations. Recent advances in chemical, biochemical and molecular detection methods have provided standardized alternatives to this microscopic approach. In this review, we examine the applicability of alternative methodologies, in particular nucleic acid based assays involving the quantitative polymerase chain reaction, for the standardized detection of airborne pollen. Published by Elsevier B.V.

  2. Nucleic acid-based methods for the early detection of sepsis in heart transplant recipients

    Directory of Open Access Journals (Sweden)

    Sarvesh Pal Singh

    2016-01-01

    Full Text Available Nucleic acid-based tests (NABTs were developed to decrease the time required to identify microorganism in the pathological specimens. The commercially available NABTs are of two types – one those can be applied to positive cultures grown in blood culture bottles and other those can be applied directly to blood samples. The latter tests are polymerase chain reaction (PCR-based assays which can amplify the existing load of microorganism nucleic acids many a times like a culture in a blood culture bottle. Both tests then identify the pathogenic organisms with the use of specific nucleic acid probes. These tests have proven useful in management of heart transplant sepsis management.

  3. Production of glucuronic acid-based polysaccharides by microbial fermentation for biomedical applications.

    Science.gov (United States)

    Cimini, Donatella; Rosa, Mario De; Schiraldi, Chiara

    2012-02-01

    This review provides an overview of the properties, different biosynthetic machineries, and biotechnological production processes of four microbially derived glucuronic acid-based polysaccharides that are of interest for diverse biomedical purposes. In particular, the utilization of hyaluronic acid and heparin sulfate in high-value medical applications is already well established, whereas chondroitin sulfate and alginate show high potential within this ever-growing field. Furthermore, new strategies exploiting genetically engineered microorganisms generated through improving naturally existing pathways or de novo designed ones are described. These new developments result in increased fermentation titers, and thereby, pave the way towards feasible, or at least improved, process economy. Moreover, these strategies also allow for the future possibility of producing tailor-made biopolymers with specified characteristics, even novel molecules. Copyright © 2012 WILEY-VCH Verlag GmbH & Co. KGaA, Weinheim.

  4. Novel Blend Membranes Based on Acid-Base Interactions for Fuel Cells

    Directory of Open Access Journals (Sweden)

    Yongzhu Fu

    2012-10-01

    Full Text Available Fuel cells hold great promise for wide applications in portable, residential, and large-scale power supplies. For low temperature fuel cells, such as the proton exchange membrane fuel cells (PEMFCs and direct methanol fuel cells (DMFCs, proton-exchange membranes (PEMs are a key component determining the fuel cells performance. PEMs with high proton conductivity under anhydrous conditions can allow PEMFCs to be operated above 100 °C, enabling use of hydrogen fuels with high-CO contents and improving the electrocatalytic activity. PEMs with high proton conductivity and low methanol crossover are critical for lowering catalyst loadings at the cathode and improving the performance and long-term stability of DMFCs. This review provides a summary of a number of novel acid-base blend membranes consisting of an acidic polymer and a basic compound containing N-heterocycle groups, which are promising for PEMFCs and DMFCs.

  5. Laser restoring the glass surface treated with acid-based paint

    Science.gov (United States)

    Strusevich, Anastasia V.; Poltaev, Yuriy A.; Sinev, Dmitrii A.

    2013-11-01

    The modern city facilities are often being attacked by graffiti artists, and increasingly vandals leave "tags" using paints, which compound based on acids, hydrofluoric or acetic commonly. These paints not only ink the surface, but also increase the surface roughness, and such impact can not be corrected by conventional cleaning. Thus, it was requested to develop technology that would not only clean the surface, but also to restore its structure by smoothing out irregularities and roughness formed after exposure in acid. In this work we investigated the effect of restoring the surface of the glass, spoiled by acid-based paint and then treated with CO2-laser. During the experiments, it was found that it is real to create the single-step laser surface restoring technology.

  6. Studies on (acid + base) equilibria in substituted (phenol + n-butylamine) systems in acetonitrile

    Energy Technology Data Exchange (ETDEWEB)

    Kozak, A. [Department of General Chemistry, University of Gdansk, Sobieskiego 18, 80-952 Gdansk (Poland); Czaja, M. [Department of General Chemistry, University of Gdansk, Sobieskiego 18, 80-952 Gdansk (Poland); Chmurzynski, L. [Department of General Chemistry, University of Gdansk, Sobieskiego 18, 80-952 Gdansk (Poland)]. E-mail: lech@chem.univ.gda.pl

    2005-08-15

    (Acid + base) equilibria, including molecular heteroconjugation ones, between n-butylamine and one of the following phenols: 2-nitrophenol, 3-nitrophenol, 4-nitrophenol, 2,4-dinitrophenol, 2,5-dinitrophenol, 3-chlorophenol, 4-chlorophenol, 2,3,4,5,6-pentachlorophenol and 2,4,6-tribromophenol have been studied potentiometrically in a protophobic polar aprotic solvent, acetonitrile. Among the phenols studied, 2,5-dinitrophenol exhibited the strongest tendency towards formation of asymmetric hydrogen bonds with n-butylamine, whereas a weakest complex was formed with 2-nitrophenol. In the (n-butylamine + 2,3,4,5,6-pentachlorophenol) and (n-butylamine + 2,4-dinitrophenol) systems proton transfer reactions occurred.

  7. Some comments upon acid-base balance in teleost fishes and its relationship to environmental temperature

    Energy Technology Data Exchange (ETDEWEB)

    Houston, A.H.

    1971-01-01

    It has been hypothesized that acid-base regulation in mammalian species is directed toward stabilization of body fluid pH, whereas among the poikilotherms control centers upon the maintenance of relative alkalinity. Consequently, given the known relationship between temperature and the dissociation constant of water reductions in mammalian body temperature should be accompanied by decreases in the OH/sup -//H/sup +/ ratio while, under similar circumstances, the pH of the poikilothermic tetrapods, extension of the concept of relative alkalinity regulation to teleost fishes is not wholly consistent with the data presently available. Recorded blood and plasma pH values for teleost fishes are generally below those reported for amphibians and reptiles, tending to fall within or below the levels observed in mammals under comparable thermal conditions. Moreover, they seemingly display little tendency to vary in an inverse fashion wth temperature.

  8. TDDFT Study of the Optical Excitation of Nucleic Acid Bases-C60 Complexes.

    Science.gov (United States)

    Tawfik, Sherif Abdulkader; Cui, X Y; Ringer, S P; Stampfl, C

    2017-11-30

    The potential of C60 as a nucleic acid base (NAB) optical sensor is theoretically explored. We investigate the adsorption of four NABs, namely, adenine, cytosine, guanine, and thymine, on C60 in the gas phase. For the optimal NAB@C60 adsorption configurations, obtained using a dispersion-corrected density functional, we calculate the vis-near-ultraviolet optical response using time-dependent density functional theory. While the isolated C60 and NAB molecules do not exhibit visible optical excitation, we find that C60/NAB conjugation gives rise to distinct spectral features in the visible range. These results suggest that C60 conjugation can be applied for photodetection of individual NABs.

  9. Role of acid-base interactions in synthesis of cordierite from talc and sillimanite group minerals

    Directory of Open Access Journals (Sweden)

    Avvakumov E.G.

    2013-01-01

    Full Text Available It has been found that the mechanical activation of mixtures of sillimanite group minerals with talc and silica additives in grinding-activating devices with periodic and flow action provides significant acceleration of their interaction with formation of cordierite at the subsequent high-temperature treatment. It is shown that the output of cordierite depends on nature of mineral: in mixture with a sillimanite it is considerably higher, than with an andalusite and kyanite, while the rate of mullitization of these minerals has opposite character. It means that the formation of mullite during heat treatment is not a limiting step in synthesis of cordierite. It is shown that the rate of reaction is determined by the difference in the acid-base properties of these minerals, which depend on the coordination of aluminum cations by oxygen ions, different for each of the modifications.

  10. Blue photoluminescence of sponge-like highly porous alumina synthesized in hydrofluoric acid based electrolytes

    Science.gov (United States)

    Ilin, D. O.; Vokhmintsev, A. S.; Martemyanov, N. A.; Weinstein, I. A.

    2017-11-01

    For the first time nanostructures of anodized aluminum oxide (AAO) were synthesized using hydrofluoric acid based electrolytes under potentiostatic mode with varied oxidation conditions. As-grown oxide layers were amorphous and had sponge-like disordered structure with ramified pores system of 50 to 300 nm diameters. All samples under daylight demonstrated blue emission with power up to 10 μW that was seen by naked eye. It was shown that integral intensity of photoluminescence (PL) emission band in 350 – 650 range increases up to 7 – 60 times depending on synthesis details. Observed PL spectra were approximated by superposition of two components with Emax = 2.74 and 2.44 eV, FWHM = 0.63 and 0.53 eV. It was substantiated that studied emission have intrinsic origin and can be attributed to F2 2+ - and F2-centers.

  11. Calculating acid-base and oxygenation status during COPD exacerbation using mathematically arterialised venous blood

    DEFF Research Database (Denmark)

    Rees, Stephen Edward; Rychwicka-Kielek, Beate A; Andersen, Bjarne F

    2012-01-01

    for exacerbation of chronic obstructive pulmonary disease (COPD). Methods: Simultaneous arterial and peripheral venous blood was analysed. Venous values were used to calculate arterial pH, PCO2 and PO2, with these compared to measured values using Bland-Altman analysis and scatter plots. Calculated values of PO2......Abstract Background: Repeated arterial puncture is painful. A mathematical method exists for transforming peripheral venous pH, PCO2 and PO2 to arterial eliminating the need for arterial sampling. This study evaluates this method to monitor acid-base and oxygenation during admission...... be calculated from peripheral venous values so as to characterise changes seen during exacerbation. Application of the method has potential to reduce arterial sampling, decrease discomfort and enable venous sampling as routine practice....

  12. Biomedical Applications of Quantum Dots, Nucleic Acid-Based Aptamers, and Nanostructures in Biosensors.

    Science.gov (United States)

    Meshik, Xenia; Farid, Sidra; Choi, Min; Lan, Yi; Mukherjee, Souvik; Datta, Debopam; Dutta, Mitra; Stroscio, Michael A

    2015-01-01

    This review is a survey of the biomedical applications of semiconductor quantum dots, nucleic acid-based aptamers, and nanosensors as molecular biosensors. It focuses on the detection of analytes in biomedical applications using (1) advances in molecular beacons incorporating semiconductor quantum dots and nanoscale quenching elements; (2) aptamer-based nanosensors on a variety of platforms, including graphene; (3) Raman scattering and surface-enhanced Raman scattering (SERS) using nanostructures for enhanced SERS spectra of biomolecules, including aptamers; and (4) the electrical and optical properties of nanostructures incorporated into molecular beacons and aptamer-based nanosensors. Research done at the University of Illinois at Chicago (UIC) is highlighted throughout since it emphasizes the specific approaches taken by the bioengineering department at UIC.

  13. Acid-base and coordination properties of Meso-substituted porphyrins in nonaqueous solutions

    Science.gov (United States)

    Pukhovskaya, S. G.; Nam, Dao Tkhe; Fien, Chan Ding; Domanina, E. N.; Ivanova, Yu. B.; Semeikin, A. S.

    2017-09-01

    Acid-base and coordination properties of alkyl and aryl meso-substituted porphyrins are studied spectrophotometrically in nonaqueous solutions. It is found that the nature of the substituent greatly affects the basicity of ligands for porphyrins characterized by a flat structure of macrocycle. The electronic effects of substituents have a much weaker influence on the kinetics of complexing. These effects could be due to the opposite orientation of some factors: an increase in the basicity and stability of the N-H bonds of porphyrin reaction centers. Dissociation constants p K b of the cationic forms of meso-substituted derivatives of porphyrin are measured. The values of p K b are in good agreement with classic concepts of the nature of substituents, particularly those indirectly included in the macrocycle through phenyl buffer rings.

  14. A Concentrated Hydrochloric Acid-based Method for Complete Recovery of DNA from Bone.

    Science.gov (United States)

    Huynen, Leon; Lambert, David M

    2015-11-01

    The successful extraction of DNA from historical or ancient animal bone is important for the analysis of discriminating genetic markers. Methods used currently rely on the digestion of bone with EDTA and proteinase K, followed by purification with phenol/chloroform and silica bed binding. We have developed a simple concentrated hydrochloric acid-based method that precludes the use of phenol/chloroform purification and can lead to a several-fold increase in DNA yield when compared to other commonly used methods. Concentrated hydrochloric acid was shown to dissolve most of the undigested bone and allowed the efficient recovery of DNA fragments <100 bases in length. This method should prove useful for the recovery of DNAs from highly degraded animal bone, such as that found in historical or ancient samples. © 2015 American Academy of Forensic Sciences.

  15. Boehmite-An Efficient and Recyclable Acid-Base Bifunctional Catalyst for Aldol Condensation Reaction.

    Science.gov (United States)

    Reshma, P C Rajan; Vikneshvaran, Sekar; Velmathi, Sivan

    2018-06-01

    In this work boehmite was used as an acid-base bifunctional catalyst for aldol condensation reactions of aromatic aldehydes and ketones. The catalyst was prepared by simple sol-gel method using Al(NO3)3·9H2O and NH4OH as precursors. The catalyst has been characterized by X-ray diffraction (XRD), Fourier Transform Infrared (FTIR), Scanning Electron Microscopy (SEM), UV-visible spectroscopy (DRS), BET surface area analyses. Boehmite is successfully applied as catalyst for the condensation reaction between 4-nitrobenzaldehyde and acetone as a model substrate giving α, β-unsaturated ketones without any side product. The scope of the reaction is extended for various substituted aldehydes. A probable mechanism has been suggested to explain the cooperative behavior of the acidic and basic sites. The catalyst is environmentally friendly and easily recovered from the reaction mixture. Also the catalyst is reusable up to 3 catalytic cycles.

  16. Acid-Base Interactions at the Molecular Level: Adhesion and Friction Studies with Interfacial Force Microscopy

    Energy Technology Data Exchange (ETDEWEB)

    Burns, A.R.; Carpick, R.W.; Houston, J.E.; Michalske, T.A.

    1998-12-09

    To examine the forces of acid-base adhesive interactions at the molecular level, we utilize the scanning probe Interracial Force Microscope (IFM). Unlike cantilever-based atomic force microscopes, the EM is a non-compliant, mechanically stable probe that provides a complete adhesive profile without jump-to-contact. In this way, we are able to quantitatively measure the work of adhesion and bond energies at well-defined, nanometer-scale single asperity contacts. In particular, we will discuss the displacement-controlled adhesive forces between self-assembled monolayer of functionalized alkanethiols strongly bound to a gold substrate and a similarly functionalized tip. We also discuss a method utilizing decoupled lateral and normal force sensors to simultaneously observe the onset of both friction and chemical bond formation. Measurements show that friction can be directly attributed to bond formation and rupture well before repulsive contact.

  17. Acid-base chemical reaction model for nucleation rates in the polluted atmospheric boundary layer.

    Science.gov (United States)

    Chen, Modi; Titcombe, Mari; Jiang, Jingkun; Jen, Coty; Kuang, Chongai; Fischer, Marc L; Eisele, Fred L; Siepmann, J Ilja; Hanson, David R; Zhao, Jun; McMurry, Peter H

    2012-11-13

    Climate models show that particles formed by nucleation can affect cloud cover and, therefore, the earth's radiation budget. Measurements worldwide show that nucleation rates in the atmospheric boundary layer are positively correlated with concentrations of sulfuric acid vapor. However, current nucleation theories do not correctly predict either the observed nucleation rates or their functional dependence on sulfuric acid concentrations. This paper develops an alternative approach for modeling nucleation rates, based on a sequence of acid-base reactions. The model uses empirical estimates of sulfuric acid evaporation rates obtained from new measurements of neutral molecular clusters. The model predicts that nucleation rates equal the sulfuric acid vapor collision rate times a prefactor that is less than unity and that depends on the concentrations of basic gaseous compounds and preexisting particles. Predicted nucleation rates and their dependence on sulfuric acid vapor concentrations are in reasonable agreement with measurements from Mexico City and Atlanta.

  18. [Clinical evaluation of acid-base status: Henderson-Hasselbalch, or Stewart-Fencl approach?

    Science.gov (United States)

    Matoušovic, Karel; Havlín, Jan; Schück, Otto

    Two approaches have been used in clinical evaluation the acid-base status: traditional (bicarbonate-centered) is based on the Henderson-Hasselbalch equation complemented by calculation of the anion gap, and more recent quantitative approach proposed by Stewart and Fencl. The latter method defines the three independent variables, which regulate pH. These include: the difference between the sum of charges carried by strong plasma cations and anions termed the strong ion difference - SID (decrease causes acidosis, and vice versa); the total concentration of the weak non-volatile acids [Atot] (inorganic phosphate and albumin, decrease causes alkalosis and vice versa), and pCO2. According to this approach, pH and bicarbonate are dependent variables. Their concentrations change if and only if one or more independent variables are altered.The main advantage of the Stewart-Fencl approach is the calculation of the concentration of plasma acids, which are not routinely measured. In the traditional approach, their presence is inferred from the anion gap. The correction of the value of anion gap according to the serum albumin level increases the specificity. This correction brings traditional approach closer to the Stewart-Fencl method that precisely calculates unmeasured strong anions by further adjustment of the corrected anion gap according to the serum phosphate, calcium and magnesium levels. The precise calculation of unmeasured anions is important in critically ill patients with the metabolic breakdown, where the traditional approach may overlook the presence of unmeasured anions. Consideration of the sodium-chloride difference draws the attention to acid-base disturbance caused by change of the strong ion difference.

  19. Sulfur and chlorine play a non-acid base role in periparturient calcium homeostasis.

    Science.gov (United States)

    Roche, J R; Morton, J; Kolver, E S

    2002-12-01

    The increased risk of periparturient hypocalcaemia through offering high-K feeds in the precalving period has been reported previously. Two experiments (experiment 1 and 2) investigated the effect of KCl fertilizer on pasture mineral concentration, the dietary cation-anion difference (DCAD), and the subsequent effect of this on periparturient plasma and urine mineral status. Experiment 2 examined the effect of precalving Mg source (MgO, MgSO4, and MgCl2) and postcalving Ca supplementation on the concentration of Ca and Mg in plasma and urine. Unexpectedly, pasture DCAD increased (P = 0.06) from 434 to 535 mEq/kg DM in experiment 1 as pasture K concentration decreased from 4.2 to 3.5%, primarily because of a corresponding and greater decrease in pasture Cl concentration (from 1.9 to 1.3%). Plasma Ca or Mg concentrations were not affected by pasture K concentration. A linear decline (P urine Mg suggested a decline in Mg absorption as pasture K increased. In experiment 2, pasture DCAD decreased (P urine pH was not affected by the declining DCAD. Postcalving plasma Ca concentration was affected by precalving Mg source with MgSO4 > MgCl2 > MgO. Differences in acid-base balance do not explain the difference between Mg salts. These results indicate that precalving dietary S and Cl concentration plays an important role in Ca homeostasis, in addition to its role in acid-base balance. Supplementation with Ca postcalving increased plasma Ca concentration for 2 d postcalving. Milk production was not affected.

  20. Is urea formation regulated primarily by acid-base balance in vivo?

    Science.gov (United States)

    Halperin, M L; Chen, C B; Cheema-Dhadli, S; West, M L; Jungas, R L

    1986-04-01

    Large quantities of ammonium and bicarbonate are produced each day from the metabolism of dietary protein. It has recently been proposed that urea synthesis is regulated by the need to remove this large load of bicarbonate. The purpose of these experiments was to test whether the primary function of ureagenesis in vivo is to remove ammonium or bicarbonate. The first series of rats were given a constant acid load as hydrochloric acid or ammonium chloride; individual rats received a constant nitrogen load at a time when their plasma acid-base status ranged from normal (pH 7.4, 28 mM HCO3) to severe metabolic acidosis (pH 6.9, 6 mM HCO3). Urea plus ammonium excretions and the blood urea, glutamine, and ammonium concentrations were monitored with time. Within the constraints of non-steady-state conditions, the rate of urea synthesis was constant and the plasma glutamine and ammonium concentrations also remained constant; thus it appears that the rate of urea synthesis was not primarily regulated by the acid-base status of the animal in vivo over a wide range of plasma ammonium concentrations. In quantitative terms, the vast bulk of the ammonium load was converted to urea over 80 min; only a small quantity of ammonium appeared as circulating glutamine or urinary ammonium. Urea synthesis was proportional to the nitrogen load. A second series of rats received sodium bicarbonate; urea synthesis was not augmented by a bicarbonate load. We conclude from these studies that the need to dispose of excess bicarbonate does not primarily determine the rate of ureagenesis in vivo. The data support the classical view that ureagenesis is controlled by the quantity of ammonium to be removed.

  1. The effect of chronic hypotonic volume expansion on the renal regulation of acid-base equilibrium.

    Science.gov (United States)

    Lowance, D C; Garfinkel, H B; Mattern, W D; Schwartz, W B

    1972-11-01

    Balance studies have been carried out to evaluate the influence of vasopressin-induced volume expansion on acid-base equilibrium in normal dogs and in dogs with steady-state metabolic acidosis induced by the administration of 5-7 mmoles/kg per day of hydrochloric acid.Hypotonic expansion in dogs with metabolic acidosis (mean plasma bicarbonate concentration 14 mEq/liter) produced a marked increase in renal acid excretion that restored plasma bicarbonate concentration to normal (20-21 mEq/liter) despite continued ingestion of acid. When water was restricted during the vasopressin period, and fluid retention thus prevented, no increase in acid excretion or plasma bicarbonate concentration occurred. From these findings we conclude that hypotonic expansion is a potent stimulus to renal hydrogen ion secretion and greatly facilitates the renal removal of an acid load. Normal dogs subjected to expansion demonstrated no change in net acid excretion or in plasma bicarbonate concentration even in the face of a marked diuresis of sodium and chloride and a reduction in plasma sodium concentration to approximately 110 mEq/liter. The animals did, however, regularly lose potassium, a finding that clearly indicates an acceleration of distal sodiumcation exchange. On the basis of these observations, and the findings in the expanded acidotic dogs, we suggest that in the expanded normal dogs acceleration of sodium-hydrogen exchange was responsible for preventing a bicarbonate diuresis and for stabilizing plasma bicarbonate concentration. These studies clearly demonstrate that chronic hypotonic expansion exerts a major influence on the renal regulation of acid-base equilibrium. The exact nature of the mechanism responsible for the increase in sodium-hydrogen exchange during hypotonic expansion remains to be determined.

  2. Acid-base balance in the developing marsupial: from ectotherm to endotherm.

    Science.gov (United States)

    Andrewartha, Sarah J; Cummings, Kevin J; Frappell, Peter B

    2014-05-01

    Marsupial joeys are born ectothermic and develop endothermy within their mother's thermally stable pouch. We hypothesized that Tammar wallaby joeys would switch from α-stat to pH-stat regulation during the transition from ectothermy to endothermy. To address this, we compared ventilation (Ve), metabolic rate (Vo2), and variables relevant to blood gas and acid-base regulation and oxygen transport including the ventilatory requirements (Ve/Vo2 and Ve/Vco2), partial pressures of oxygen (PaO2), carbon dioxide (PaCO2), pHa, and oxygen content (CaO2) during progressive hypothermia in ecto- and endothermic Tammar wallabies. We also measured the same variables in the well-studied endotherm, the Sprague-Dawley rat. Hypothermia was induced in unrestrained, unanesthetized joeys and rats by progressively dropping the ambient temperature (Ta). Rats were additionally exposed to helox (80% helium, 20% oxygen) to facilitate heat loss. Respiratory, metabolic, and blood-gas variables were measured over a large body temperature (Tb) range (∼15-16°C in both species). Ectothermic joeys displayed limited thermogenic ability during cooling: after an initial plateau, Vo2 decreased with the progressive drop in Tb. The Tb of endothermic joeys and rats fell despite Vo2 nearly doubling with the initiation of cold stress. In all three groups the changes in Vo2 were met by changes in Ve, resulting in constant Ve/Vo2 and Ve/Vco2, blood gases, and pHa. Thus, although thermogenic capability was nearly absent in ectothermic joeys, blood acid-base regulation was similar to endothermic joeys and rats. This suggests that unlike some reptiles, unanesthetized mammals protect arterial blood pH with changing Tb, irrespective of their thermogenic ability and/or stage of development.

  3. Drug solubilization by amino acid based polymeric nanoparticles: Characterization and biocompatibility studies.

    Science.gov (United States)

    Dutta, Pranabesh; Dey, Joykrishna

    2011-12-15

    Three novel amino acid based amphiphilic copolymers, poly(sodium N acryloyl-L-aminoacidate-co-dodecylacrylamide) (where aminoacidate=glycinate, leucinate, and phenylalaninate) were synthesized and characterized. These hydrophobically modified polyelectrolytes (HMPs) formed spheroidal nanoparticular aggregates above a critical aggregation concentration with average diameter 20-200nm and overall negative charges as indicated by dynamic light scattering (DLS) and zeta-potential (ζ≈-10.2 to -25.2) measurements, respectively. The size and shape of the nanostructures was confirmed by transmission electron microscopic images. The micropolarity and microviscosity of the nanosize aggregates were investigated by fluorescence probe method using extrinsic probes like N-phenyl-1-naphthylamine, pyrene, and 1,6-diphenyl-1,3,5-hexatriene. The stability of the copolymer micelles was investigated as a function of pH and temperature using fluorescence and DLS techniques. Both fluorescence probe and DLS data suggest that the copolymer micelles are highly stable under physiological condition (pH 7.4, 37.4°C). These HMP micelles were evaluated primarily as a drug delivery system. The ability of the copolymers to encapsulate hydrophobic drug was investigated using a poorly water-soluble antifungal drug, griseofulvin. Biocompability of the HMPs were examined by hemolytic and cytotoxicity assay. All three HMPs were non-hemolytic up to the tested concentration of about 1.0g/L. In vitro biological assay indicated that these new copolymers were also less toxic against 3T3 mammalian cell line. The studies suggest that these newly conceived amino acid based biocompatible polymeric nanoparticles might have potential application as injectible drug delivery systems which can enhance the therapeutic index of poorly water-soluble clinically challenging drugs. Copyright © 2011 Elsevier B.V. All rights reserved.

  4. Effects of Acute Normovolemic Anemia on Hemodynamic Parameters and Acid-Base Balance in Dogs

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    Tatiana Champion

    2011-01-01

    Full Text Available The aim of this study was to evaluate the hemodynamic and acid-base status of dogs subjected to acute normovolemic anemia. The dogs (n=10 were evaluated 15 minutes and 24 hours after induction of anemia (hematocrit below 18% with blood withdrawal and simultaneously replacement of same volume of Ringer's lactate solution and hydroxyethyl starch-based solution in a 2 : 1 ratio. The cardiac output was measured by Doppler echocardiography and blood pressure by oscillometric device, and posteriorly hemodynamic parameters were calculated. The anemic groups had increase in cardiac index (P<.05 (3.82±1.05 to 5.86±1.49 and 5.81±1.63 L/min × m2 and decreases (P<.05 in the indices of total peripheral resistance (6797.81±3060.22 to 3220.14±1275.02 and 3887.74±1394.89 dina⋅seg/cm5 × m2 and oxygen delivery (7942.84±3344.00 to 4021.68±1627.00 and 4430.82±1402.61 mL/min × m2, respectively. There were no significant changes in pH, but PaO2 and SaO2 values were increased, and PaCO2 reduced in anemic dogs (P<.05. Therefore, acute normovolemic anemia can create significant hemodynamic changes and despite some hemogasometric changes, there were no changes in the acid-base status in dogs.

  5. Carbon dioxide induced plasticity of branchial acid-base pathways in an estuarine teleost

    Science.gov (United States)

    Allmon, Elizabeth B.; Esbaugh, Andrew J.

    2017-04-01

    Anthropogenic CO2 is expected to drive ocean pCO2 above 1,000 μatm by 2100 - inducing respiratory acidosis in fish that must be corrected through branchial ion transport. This study examined the time course and plasticity of branchial metabolic compensation in response to varying levels of CO2 in an estuarine fish, the red drum, which regularly encounters elevated CO2 and may therefore have intrinsic resilience. Under control conditions fish exhibited net base excretion; however, CO2 exposure resulted in a dose dependent increase in acid excretion during the initial 2 h. This returned to baseline levels during the second 2 h interval for exposures up to 5,000 μatm, but remained elevated for exposures above 15,000 μatm. Plasticity was assessed via gene expression in three CO2 treatments: environmentally realistic 1,000 and 6,000 μatm exposures, and a proof-of-principle 30,000 μatm exposure. Few differences were observed at 1,000 or 6,000 μatm however, 30,000 μatm stimulated widespread up-regulation. Translocation of V-type ATPase after 1 h of exposure to 30,000 μatm was also assessed; however, no evidence of translocation was found. These results indicate that red drum can quickly compensate to environmentally relevant acid-base disturbances using baseline cellular machinery, yet are capable of plasticity in response to extreme acid-base challenges.

  6. Investigations of (acid+base) equilibria in systems modelling interactions occurring in biomolecules

    Energy Technology Data Exchange (ETDEWEB)

    Kozak, Anna [Department of General Chemistry, University of Gdansk, Sobieskiego 18, 80-952 Gdansk (Poland); Czaja, Malgorzata [Department of General Chemistry, University of Gdansk, Sobieskiego 18, 80-952 Gdansk (Poland); Chmurzynski, Lech [Department of General Chemistry, University of Gdansk, Sobieskiego 18, 80-952 Gdansk (Poland)]. E-mail: lech@chem.univ.gda.pl

    2006-05-15

    By using the potentiometric microtitration method, acidity constants, K{sub a}, anionic, K{sub AHA{sup -}}, and cationic, K{sub BHB{sup +}}, homoconjugation constants, as well as molecular heteroconjugation, K{sub BHA}, constants have been determined in (acid+base) systems formed by the following compounds: acetic acid, phenol, n-butylamine, imidazole, and 4(5)-methylimidazole. These compounds constitute fragments of the side chains of amino acids capable of proton exchange in active sites of enzymes. The (acid+base) equilibria were studied in five polar solvents of different properties, namely in aprotic protophobic acetonitrile, acetone and propylene carbonate, in aprotic protophilic dimethyl sulfoxide and in amphiprotic methanol. The lowest values of the acidity constants of the molecular and cationic acids have been found in aprotic protophobic polar solvents - acetonitrile, propylene carbonate and acetone. Their acid strength have been found to depend on solvent basicity expressed as donor numbers, DN. These media, in particular acetonitrile and acetone, are also favourable for establishing molecular homo- and heteroconjugation equilibria. The most stable homocomplexes are formed in the case of acetic acid (K{sub AHA{sup -}} values range from 2.26 to 3.56 in these media, being more than an order of magnitude higher than those for the remaining compounds). The magnitudes of lgK{sub BHA} reveal that the most stable heterocomplexes are formed by n-butylamine and acetic acid that are characterized by the smallest differences in pK{sub a} values.

  7. Correlating multidimensional fetal heart rate variability analysis with acid-base balance at birth.

    Science.gov (United States)

    Frasch, Martin G; Xu, Yawen; Stampalija, Tamara; Durosier, Lucien D; Herry, Christophe; Wang, Xiaogang; Casati, Daniela; Seely, Andrew Je; Alfirevic, Zarko; Gao, Xin; Ferrazzi, Enrico

    2014-12-01

    Fetal monitoring during labour currently fails to accurately detect acidemia. We developed a method to assess the multidimensional properties of fetal heart rate variability (fHRV) from trans-abdominal fetal electrocardiogram (fECG) during labour. We aimed to assess this novel bioinformatics approach for correlation between fHRV and neonatal pH or base excess (BE) at birth.We enrolled a prospective pilot cohort of uncomplicated singleton pregnancies at 38-42 weeks' gestation in Milan, Italy, and Liverpool, UK. Fetal monitoring was performed by standard cardiotocography. Simultaneously, with fECG (high sampling frequency) was recorded. To ensure clinician blinding, fECG information was not displayed. Data from the last 60 min preceding onset of second-stage labour were analyzed using clinically validated continuous individualized multiorgan variability analysis (CIMVA) software in 5 min overlapping windows. CIMVA allows simultaneous calculation of 101 fHRV measures across five fHRV signal analysis domains. We validated our mathematical prediction model internally with 80:20 cross-validation split, comparing results to cord pH and BE at birth.The cohort consisted of 60 women with neonatal pH values at birth ranging from 7.44 to 6.99 and BE from -0.3 to -18.7 mmol L(-1). Our model predicted pH from 30 fHRV measures (R(2) = 0.90, P acid-base balance at birth. Further refinement and validation in larger cohorts are needed. These new measurements of fHRV might offer a new opportunity to predict fetal acid-base balance at birth.

  8. Crystalloid strong ion difference determines metabolic acid-base change during in vitro hemodilution.

    Science.gov (United States)

    Morgan, Thomas J; Venkatesh, Balasubramanian; Hall, Jonathan

    2002-01-01

    To determine the relationship between the strong ion difference (SID) of a diluting crystalloid and its metabolic acid-base effects on in vitro blood dilution. Prospective in vitro study. University research laboratory. Normal human blood. Three solutions were prepared, each with [Na] 140 mmol/L. [Cl-] for solutions 1, 2, and 3 was 120, 110, and 100 mmol/L, respectively, the other anion being HCO3-. SID values were thus 20, 30, and 40 mEq/L, respectively. Serial dilutions of well-oxygenated fresh venous blood were performed anaerobically by using each of solutions 1-3 as well as 0.9% saline (SID = 0 mEq/L) and Hartmann's solution (SID = -4 mEq/L). Blood gas and electrolyte analyses were performed before and after each dilution. Apart from dilutions with solution 3 (crystalloid SID 40 mEq/L) during which plasma SID did not change, plasma SID decreased during hemodilution. In contrast, base excess increased during hemodilution with solutions 3 and 2 (crystalloid SID 40 mEq/L and 30 mEq/L, respectively) and decreased only with the remaining three solutions. The relationships between hemoglobin concentrations and both plasma SID and whole blood base excess throughout dilution were linear, with slopes proportional to the SID of the diluent in each case. Linear regression revealed that the SID of crystalloid producing a zero base excess/hemoglobin concentration slope during blood dilution (i.e., no change in metabolic acid-base status) is 23.7 mEq/L. On in vitro hemodilution, there is a simple linear relationship between diluent crystalloid SID and the rate and direction of change of plasma SID and whole blood base excess. Direct extrapolation to in vivo situations such as acute normovolemic hemodilution and large volume correction of extracellular fluid deficits requires experimental confirmation.

  9. [ACID-BASE MODULATION OF LYSOZYME ACTIVITY IN MEDIUM FOR CULTIVATION OF ENTEROBACTERIA].

    Science.gov (United States)

    Andryuschenko, S V; Perunova, N B

    2015-01-01

    Determination of modulating effect of acid-base state of medium for cultivation of enterobacteria on activity of C-type lysozyme. Escherichia coli BL21 (DE3) strain for protein expression, Escherichia coli K12 MG1655 model strain, Escherichia coli No. 242 strain, isolated from intestine biotope; 2 Klebsiella pneumoniae strains, one of those contained plasmid homologue of periplasmatic lysozyme inhibitor gene pliC; 1 typical Salmonella enterica ATCC 14028 strain and a Micrococcus luteus ATCC 15307 strain as a control--served as material for the study. The bacteria were cultivated for 24 hours in 2 ml of liquid medium LB at 37 degrees C, 250 rpm. Determination of antilysozyme activity (ALA) was carried out by a photonepehlometrical method according to O.V. Bukharin et al. (1999) with alterations. All the studied microorganisms, including Micrococcus luteus, at the specified conditions 24 hours after cultivation were established to change the pH of the liquid nutrient medium LB from the initial value of 6.6 ± 0.1 to 8.2 ± 0.2 units. ALA determination in the cultivation medium without buffer correction was accompanied by a decline of lysozyme activity at an order of magnitude. The effect was absent during ALA measurement by a standard technique. The local shift of acid-base state of biotope under the conditions of buffer system insufficiency results in a reversible alteration of antimicrobial activity of muramidase, that among other non-specific factors of the environment determines the background of interactions on the level of associative symbiosis. This aspect should be taken into consideration during development of models, that are close to real conditions of microsymbiocenotical interactions.

  10. Complicated pregnancies in inherited distal renal tubular acidosis: importance of acid-base balance.

    Science.gov (United States)

    Seeger, Harald; Salfeld, Peter; Eisel, Rüdiger; Wagner, Carsten A; Mohebbi, Nilufar

    2017-06-01

    Inherited distal renal tubular acidosis (dRTA) is caused by impaired urinary acid excretion resulting in hyperchloremic metabolic acidosis. Although the glomerular filtration rate (GFR) is usually preserved, and hypertension and overt proteinuria are absent, it has to be considered that patients with dRTA also suffer from chronic kidney disease (CKD) with an increased risk for adverse pregnancy-related outcomes. Typical complications of dRTA include severe hypokalemia leading to cardiac arrhythmias and paralysis, nephrolithiasis and nephrocalcinosis. Several physiologic changes occur in normal pregnancy including alterations in acid-base and electrolyte homeostasis as well as in GFR. However, data on pregnancy in women with inherited dRTA are scarce. We report the course of pregnancy in three women with hereditary dRTA. Complications observed were severe metabolic acidosis, profound hypokalemia aggravated by hyperemesis gravidarum, recurrent urinary tract infection (UTI) and ureteric obstruction leading to renal failure. However, the outcome of all five pregnancies (1 pregnancy each for mothers n. 1 and 2; 3 pregnancies for mother n. 3) was excellent due to timely interventions. Our findings highlight the importance of close nephrologic monitoring of women with inherited dRTA during pregnancy. In addition to routine assessment of creatinine and proteinuria, caregivers should especially focus on acid-base status, plasma potassium and urinary tract infections. Patients should be screened for renal obstruction in the case of typical symptoms, UTI or renal failure. Furthermore, genetic identification of the underlying mutation may (a) support early nephrologic referral during pregnancy and a better management of the affected woman, and (b) help to avoid delayed diagnosis and reduce complications in affected newborns.

  11. Acute regulation of hematocrit and acid-base balance in chicken embryos in response to severe intrinsic hypercapnic hypoxia.

    Science.gov (United States)

    Andrewartha, Sarah J; Tazawa, Hiroshi; Burggren, Warren W

    2014-05-01

    The regulation of blood acid-base balance and hematology in day 15 chicken embryos in response to partial water submersion (with egg's air cell in air) and complete submersion producing severe intrinsic hypercapnic hypoxia and recovery in air was studied. The acid-base disturbance during submersion was characterized by initial rapid respiratory changes and then superseded by metabolic processes, resulting in a large progressive hysteresis. Throughout submersion and recovery, blood lactate concentration changed swiftly along with the changes in bicarbonate concentration ([HCO3(-)]), indicating that anaerobic glycolysis determined overall acid-base disturbances. Both partial and complete submersion produced large, rapid increases in hematocrit through proportional increases in mean corpuscular volume and red blood cell concentration. Death ensued once the internal pool of O2 was exhausted and/or the acid-base disturbance became too severe for survival (i.e., [HCO3(-)]a<∼10mmolL(-1)). However, embryos recovered from acid-base and hematological disturbances within 120min recovery in air after short bouts of complete (20min) or partial (60min) submersion, suggesting that shorter severe intrinsic hypercapnic hypoxia does not compromise viability of embryos. Copyright © 2014. Published by Elsevier B.V.

  12. Acid-base equilibrium dynamics in methanol and dimethyl sulfoxide probed by two-dimensional infrared spectroscopy.

    Science.gov (United States)

    Lee, Chiho; Son, Hyewon; Park, Sungnam

    2015-07-21

    Two-dimensional infrared (2DIR) spectroscopy, which has been proven to be an excellent experimental method for studying thermally-driven chemical processes, was successfully used to investigate the acid dissociation equilibrium of HN3 in methanol (CH3OH) and dimethyl sulfoxide (DMSO) for the first time. Our 2DIR experimental results indicate that the acid-base equilibrium occurs on picosecond timescales in CH3OH but that it occurs on much longer timescales in DMSO. Our results imply that the different timescales of the acid-base equilibrium originate from different proton transfer mechanisms between the acidic (HN3) and basic (N3(-)) species in CH3OH and DMSO. In CH3OH, the acid-base equilibrium is assisted by the surrounding CH3OH molecules which can directly donate H(+) to N3(-) and accept H(+) from HN3 and the proton migrates through the hydrogen-bonded chain of CH3OH. On the other hand, the acid-base equilibrium in DMSO occurs through the mutual diffusion of HN3 and N3(-) or direct proton transfer. Our 2DIR experimental results corroborate different proton transfer mechanisms in the acid-base equilibrium in protic (CH3OH) and aprotic (DMSO) solvents.

  13. Degree of glutathione deficiency and redox imbalance depend on subtype of mitochondrial disease and clinical status.

    Directory of Open Access Journals (Sweden)

    Gregory M Enns

    Full Text Available Mitochondrial disorders are associated with decreased energy production and redox imbalance. Glutathione plays a central role in redox signaling and protecting cells from oxidative damage. In order to understand the consequences of mitochondrial dysfunction on in vivo redox status, and to determine how this varies by mitochondrial disease subtype and clinical severity, we used a sensitive tandem mass spectrometry assay to precisely quantify whole blood reduced (GSH and oxidized (GSSG glutathione levels in a large cohort of mitochondrial disorder patients. Glutathione redox potential was calculated using the Nernst equation. Compared to healthy controls (n = 59, mitochondrial disease patients (n = 58 as a group showed significant redox imbalance (redox potential -251 mV ± 9.7, p<0.0001 with an increased level of oxidation by ∼ 9 mV compared to controls (-260 mV ± 6.4. Underlying this abnormality were significantly lower whole blood GSH levels (p = 0.0008 and GSH/GSSG ratio (p = 0.0002, and significantly higher GSSG levels (p<0.0001 in mitochondrial disease patients compared to controls. Redox potential was significantly more oxidized in all mitochondrial disease subgroups including Leigh syndrome (n = 15, electron transport chain abnormalities (n = 10, mitochondrial encephalomyopathy, lactic acidosis and stroke-like episodes (n = 8, mtDNA deletion syndrome (n = 7, mtDNA depletion syndrome (n = 7, and miscellaneous other mitochondrial disorders (n = 11. Patients hospitalized in metabolic crisis (n = 7 showed the greatest degree of redox imbalance at -242 mV ± 7. Peripheral whole blood GSH and GSSG levels are promising biomarkers of mitochondrial dysfunction, and may give insights into the contribution of oxidative stress to the pathophysiology of the various mitochondrial disorders. In particular, evaluation of redox potential may be useful in monitoring of clinical status or response to redox-modulating therapies in clinical trials.

  14. Framework for interpretation of trypsin-antitrypsin imbalance and genetic heterogeneity in pancreatitis.

    Science.gov (United States)

    Lin, Kun; Gao, Feng; Chen, Qingquan; Liu, Qicai; Chen, Shu

    2015-01-01

    Early intracellular premature trypsinogen activation was interpreted as the key initiator of pancreatitis. When the balance in the homeostasis of trypsin and antitrypsin system is disequilibrated, elevated aggressive enzymes directly attack the pancreatic tissue, which leads to pancreatic destruction and inflammation. However, trypsin alone is not enough to cause complications in pancreatitis, which may play a crucial role in modulating signaling events in the initial phase of the disease. NFκB activation is the major inflammatory pathway involved in the occurrence and development of pancreatitis and it can be induced by intrapancreatic activation of trypsinogen. Synthesis of trypsinogen occurs in endoplasmic reticulum (ER), and ER stress is an important early acinar cell event. Components of ER stress response are known to be able to trigger cell death as well as NFκB signaling cascade. The strongest evidence supporting the trypsin-centered theory is that gene mutations, which lead to the generation of more trypsin, or reduce the activity of trypsin inhibitors or trypsin degradation, are associated with pancreatitis. Thus, trypsin-antitrypsin imbalance may be the first step leading to pancreatic autodigestion and inducing other pathways. Continued experimental studies are necessary to determine the specific relationships between trypsin-antitrypsin imbalance and genetic heterogeneity in pancreatitis. In this article, we review the latest advances that contributed to the understanding of the basic mechanisms behind the occurrence and development of pancreatitis with a focus on the interpretation of trypsin-antitrypsin imbalance and their relationships with other inflammation pathways. We additionally highlight genetic predispositions to pancreatitis and possible mechanisms associated with them.

  15. Electrolytes imbalance in saltwater near-drowning victims in the Gulf of Thailand.

    Science.gov (United States)

    Yongsiri, Somchai; Dinchuthai, Pakapan; Thammakumpee, Jiranuch; Prongnamchai, Suriya; Chueansuwan, Rachaneeporn; Tangjaturonrasme, Siriporn; Chaivanit, Pechngam

    2013-10-01

    Near-drowning victims in saltwater are expected to have multiple electrolytes imbalance that affected treatment outcome. There are limited data about these parameters in Thailand to guide the treatment plan. To study the characteristic of electrolytes imbalance in saltwater near-drowning victims in the Gulf of Thailand. Retrospective analytic study of 39 medical records of near-drowning patients admitted to Burapha University Hospital between 2000 and 2010. Characteristics of the patients and serum electrolytes were analyzed by SPSS version 19 for windows. The study included 23 male, 16 female patients. Average age was 14.46 +/- 11.15 years and 19/39 (48.72%) patients were aged 10 or less. The following electrolytes imbalance were identified, hypokalemia 8/39 (20.51%), hypernatremia 12/39 (30.77%), hyperchloremia 15/39 (38.46%), high anion gap 23/39 (58.97%), and hypobicarbonatemia 28/39 (71.79%). Seven out of eight patients in the hypokalemia group were in the high anion gap group. Mean SpO2 in the patients who had high anion gap was significantly lower than those who had normal anion gap (87.06 +/- 17.68% vs. 95.8 +/- 5.94% p = 0.031) without difference in systolic blood pressure (112.59 +/- 14.63 vs. 105.67 +/- 13.98 p = 0.159). Those who were hypotensive significantly had lower bicarbonate (17.00 +/- 3.51 vs. 20.59 +/- 3.81 p = 0.038) and higher anion gap (19.29 +/- 1.799 vs. 16.25 +/- 6.25 p = 0.025) than normotensive patients. Hypobicarbonatemia, high anion gap, hypernatremia, and hypokalemia were common in saltwater near-drowning patients in the Gulf of Thailand. The cause of high anion gap was probably due to hypoxia and hypotension.

  16. A case of difficult management of fluid-electrolyte imbalance in choroid plexus papilloma.

    Science.gov (United States)

    Saito, Atsushi; Nishimura, Shinjitsu; Fujita, Tomoaki; Sasaki, Tatsuya; Nishijima, Michiharu

    2014-01-01

    A 22-month-old boy presented with nausea and gradual deterioration of gait disturbance. Computed tomography (CT) demonstrated an intraventricular mass lesion in the right lateral ventricle. He was referred to our department 3 weeks after onset. Acute hydrocephalus gradually proceeded 4 days after admission, and external ventricular drainage (EVD) was performed. EVD revealed cerebrospinal fluid (CSF) overproduction (800-1,500 mL/day) under constant pressure of 10 cm H2O above external auditory meatus. Magnetic resonance imaging showed a multi-lobular mass in the inferior horn of the right lateral ventricle. A choroid plexus tumor was suspected. The ratio of blood urea nitrogen:creatinine (BUN:Cre) remained between 30 and 40, and hemoglobin was between 14.0-17.0 mg/dL, suggesting marked dehydration. Serum sodium varied between 117 and 140 mmol/L, and serum potassium between 2.2 mmol/L and 6.9 mmol/L. The amount of EVD was unstable and fluid balance management was difficult. Hypotonic fluid with sodium chloride supplement was used to adjust the fluid and electrolyte imbalance. Surgical removal of the tumor was performed 6 days after EVD and tumor was grossly and totally removed. The high BUN:Cre ratio decreased to about 15 and hemoglobin recovered to 7.5-9.0 mg/dL after removal. Electrolytes returned to the normal range. Overproduction of CSF also markedly improved to electrolyte imbalance due to over-drainage after EVD, which could not be effectively controlled before tumor removal. Cautious fluid management and emergent surgical resection might be required to manage the overproduction of CSF and fluid-electrolyte imbalance.

  17. Imbalances in T Cell-Related Transcription Factors Among Patients with Hashimoto’s Thyroiditis

    Directory of Open Access Journals (Sweden)

    Vahid Safdari

    2017-06-01

    Full Text Available Objectives: Imbalances in effector T cell functioning have been associated with a number of autoimmune diseases, including Hashimoto’s thyroiditis (HT. Differentiation of effector T helper (Th 1, Th2, Th17 and regulatory T cell (Treg lymphocytes is regulated by transcription factors, including Th1-specific T box (T-bet, GATA binding protein-3 (GATA3, retinoid-related orphan receptor (ROR-α and forkhead box P3 (FOXP3. This study aimed to investigate Th1/Th2, Th1/Treg, Th2/Treg and Th17/Treg balances at the level of these transcription factors. Methods: This study took place between October 2015 and August 2016. Peripheral blood mononuclear cells were collected from a control group of 40 healthy women recruited from the Zahedan University of Medical Sciences, Zahedan, Iran, and a patient group of 40 women with HT referred to the Hazrat Ali Asghar Hospital, Zahedan. Total ribonucleic acid extraction was performed and the gene expression of transcription factors was quantitated using a real-time polymerase chain reaction technique. Results: Expression of T-bet and GATA3 was significantly elevated, while FOXP3 expression was significantly diminished among HT patients in comparison with the controls (P = 0.03, 0.01 and 0.05, respectively. Expression of RORα was higher among HT patients, although this difference was not significant (P = 0.15. Expression of T-bet/FOXP3, GATA3/FOXP3 and RORα/FOXP3 ratios were increased among HT patients in comparison with the controls (P <0.02, <0.01 and <0.01, respectively. Conclusion: These results indicate that HT patients have imbalances in Th1/Treg, Th2/Treg and Th17/Treg lymphocytes at the level of the transcription factors, deviating towards Th1, Th2 and Th17 cells. Correction of these imbalances may therefore be therapeutic.

  18. Framework for Interpretation of Trypsin–antitrypsin Imbalance and Genetic Heterogeneity in Pancreatitis

    Science.gov (United States)

    Lin, Kun; Gao, Feng; Chen, Qingquan; Liu, Qicai; Chen, Shu

    2015-01-01

    Early intracellular premature trypsinogen activation was interpreted as the key initiator of pancreatitis. When the balance in the homeostasis of trypsin and antitrypsin system is disequilibrated, elevated aggressive enzymes directly attack the pancreatic tissue, which leads to pancreatic destruction and inflammation. However, trypsin alone is not enough to cause complications in pancreatitis, which may play a crucial role in modulating signaling events in the initial phase of the disease. NFκB activation is the major inflammatory pathway involved in the occurrence and development of pancreatitis and it can be induced by intrapancreatic activation of trypsinogen. Synthesis of trypsinogen occurs in endoplasmic reticulum (ER), and ER stress is an important early acinar cell event. Components of ER stress response are known to be able to trigger cell death as well as NFκB signaling cascade. The strongest evidence supporting the trypsin-centered theory is that gene mutations, which lead to the generation of more trypsin, or reduce the activity of trypsin inhibitors or trypsin degradation, are associated with pancreatitis. Thus, trypsin–antitrypsin imbalance may be the first step leading to pancreatic autodigestion and inducing other pathways. Continued experimental studies are necessary to determine the specific relationships between trypsin–antitrypsin imbalance and genetic heterogeneity in pancreatitis. In this article, we review the latest advances that contributed to the understanding of the basic mechanisms behind the occurrence and development of pancreatitis with a focus on the interpretation of trypsin–antitrypsin imbalance and their relationships with other inflammation pathways. We additionally highlight genetic predispositions to pancreatitis and possible mechanisms associated with them. PMID:26228362

  19. Causes and consequences of adult sex ratio imbalance in a historical U.S. population.

    Science.gov (United States)

    Schacht, Ryan; Smith, Ken R

    2017-09-19

    The responsiveness of individuals to partner availability has been well-documented across the literature. However, there is disagreement regarding the direction of the consequences of sex ratio imbalance. Specifically, does an excess of males or females promote male-male mating competition? In an attempt to clarify the role of the adult sex ratio (ASR) on behaviour, here we evaluate both competing and complimentary expectations derived from theory across the social and biological sciences. We use data drawn from a historical, nineteenth century population in North America and target several life-history traits thought to be affected by partner availability: age at first birth, relationship status, completed fertility and longevity. Furthermore, we assess the role of various contributors to a population's ASR. We find that both the contributors to and consequences of sex ratio imbalance vary over time. Our results largely support predictions of greater male pairbond commitment and lesser male mating effort, as well as elevated bargaining power of women in response to female scarcity. After reviewing our findings, and others from across the literature, we highlight the need to adjust predictions in response to ASR imbalance by the: (i) culturally mediated mating arena, (ii) variable role of demographic inputs across time and place, (iii) constraints to behavioural outcomes across populations, and (iv) ability and accuracy of individuals to assess partner availability.This article is part of the themed issue 'Adult sex ratios and reproductive strategies: a critical re-examination of sex differences in human and animal societies'. © 2017 The Author(s).

  20. Autonomic Imbalance as a Predictor of Metabolic Risks, Cardiovascular Disease, Diabetes, and Mortality.

    Science.gov (United States)

    Wulsin, Lawson R; Horn, Paul S; Perry, Jennifer L; Massaro, Joseph M; D'Agostino, Ralph B

    2015-06-01

    Identifying novel early predictors of metabolic disorders is essential to improving effective primary prevention. The objectives were to examine the contribution of two measures of autonomic imbalance, resting heart rate (RHR) and heart rate variability (HRV), on the development of five metabolic risk outcomes, and on cardiovascular disease, diabetes, and early mortality. This study was a secondary analysis of prospective data from Offspring Cohort participants (N = 1882) in the Framingham Heart Study (FHS). Participants at FHS Exam 3 (1983-1987) with 1) age years 18 or older, and 2) data on RHR, HRV, and five measures of metabolic risk (blood pressure, fasting glucose, triglycerides, high-density lipoprotein [HDL] cholesterol, and body mass index [BMI]) at three follow-up visits over 12 years. We conducted a backward elimination variable selection procedure on a logistic regression model, using baseline RHR, HRV, age, sex, and smoking status to predict the odds of developing a specific metabolic risk. Measures included hyperglycemia, high blood pressure, high triglycerides, low HDL cholesterol, and high BMI over 12 years; incident diabetes, cardiovascular disease, and early mortality over 20 years. RHR and HRV, along with sex, age, and smoking were significant predictors of high blood pressure, hyperglycemia, and a diagnosis of diabetes within 12 years. RHR and HRV also predicted the development of cardiovascular disease and early mortality for most of the sample. In this community sample two measures of autonomic imbalance predicted multiple poor metabolic outcomes and mortality, making autonomic imbalance a potentially worthy target for intervention studies to reduce risks for cardiovascular disorders, diabetes, and early death.

  1. Class imbalance in unsupervised change detection - A diagnostic analysis from urban remote sensing

    Science.gov (United States)

    Leichtle, Tobias; Geiß, Christian; Lakes, Tobia; Taubenböck, Hannes

    2017-08-01

    Automatic monitoring of changes on the Earth's surface is an intrinsic capability and simultaneously a persistent methodological challenge in remote sensing, especially regarding imagery with very-high spatial resolution (VHR) and complex urban environments. In order to enable a high level of automatization, the change detection problem is solved in an unsupervised way to alleviate efforts associated with collection of properly encoded prior knowledge. In this context, this paper systematically investigates the nature and effects of class distribution and class imbalance in an unsupervised binary change detection application based on VHR imagery over urban areas. For this purpose, a diagnostic framework for sensitivity analysis of a large range of possible degrees of class imbalance is presented, which is of particular importance with respect to unsupervised approaches where the content of images and thus the occurrence and the distribution of classes are generally unknown a priori. Furthermore, this framework can serve as a general technique to evaluate model transferability in any two-class classification problem. The applied change detection approach is based on object-based difference features calculated from VHR imagery and subsequent unsupervised two-class clustering using k-means, genetic k-means and self-organizing map (SOM) clustering. The results from two test sites with different structural characteristics of the built environment demonstrated that classification performance is generally worse in imbalanced class distribution settings while best results were reached in balanced or close to balanced situations. Regarding suitable accuracy measures for evaluating model performance in imbalanced settings, this study revealed that the Kappa statistics show significant response to class distribution while the true skill statistic was widely insensitive to imbalanced classes. In general, the genetic k-means clustering algorithm achieved the most robust results

  2. Chromosomal imbalances in four new uterine cervix carcinoma derived cell lines

    Directory of Open Access Journals (Sweden)

    Vázquez Guelaguetza

    2003-03-01

    Full Text Available Abstract Background Uterine cervix carcinoma is the second most common female malignancy worldwide and a major health problem in Mexico, representing the primary cause of death among the Mexican female population. High risk human papillomavirus (HPV infection is considered to be the most important risk factor for the development of this tumor and cervical carcinoma derived cell lines are very useful models for the study of viral carcinogenesis. Comparative Genomic Hybridization (CGH experiments have detected a specific pattern of chromosomal imbalances during cervical cancer progression, indicating chromosomal regions that might contain genes that are important for cervical transformation. Methods We performed HPV detection and CGH analysis in order to initiate the genomic characterization of four recently established cervical carcinoma derived cell lines from Mexican patients. Results All the cell lines were HPV18 positive. The most prevalent imbalances in the cell lines were gains in chromosomes 1q23-q32, 3q11.2-q13.1, 3q22-q26.1, 5p15.1-p11.2, this alteration present as a high copy number amplification in three of the cell lines, 7p15-p13, 7q21, 7q31, 11q21, and 12q12, and losses in 2q35-qter, 4p16, 6q26-qter, 9q34 and 19q13.2-qter. Conclusions Analysis of our present findings and previously reported data suggest that gains at 1q31-q32 and 7p13-p14, as well as losses at 6q26-q27 are alterations that might be unique for HPV18 positive cases. These chromosomal regions, as well as regions with high copy number amplifications, coincide with known fragile sites and known HPV integration sites. The general pattern of chromosomal imbalances detected in the cells resembled that found in invasive cervical tumors, suggesting that the cells represent good models for the study of cervical carcinoma.

  3. A mathematical analysis to address the 6 degree-of-freedom segmental power imbalance.

    Science.gov (United States)

    Ebrahimi, Anahid; Collins, John D; Kepple, Thomas M; Takahashi, Kota Z; Higginson, Jill S; Stanhope, Steven J

    2018-01-03

    Segmental power is used in human movement analyses to indicate the source and net rate of energy transfer between the rigid bodies of biomechanical models. Segmental power calculations are performed using segment endpoint dynamics (kinetic method). A theoretically equivalent method is to measure the rate of change in a segment's mechanical energy state (kinematic method). However, these two methods have not produced experimentally equivalent results for segments proximal to the foot, with the difference in methods deemed the "power imbalance." In a 6 degree-of-freedom model, segments move independently, resulting in relative segment endpoint displacement and non-equivalent segment endpoint velocities at a joint. In the kinetic method, a segment's distal end translational velocity may be defined either at the anatomical end of the segment or at the location of the joint center (defined here as the proximal end of the adjacent distal segment). Our mathematical derivations revealed the power imbalance between the kinetic method using the anatomical definition and the kinematic method can be explained by power due to relative segment endpoint displacement. In this study, we tested this analytical prediction through experimental gait data from nine healthy subjects walking at a typical speed. The average absolute segmental power imbalance was reduced from 0.023 to 0.046 W/kg using the anatomical definition to ≤0.001 W/kg using the joint center definition in the kinetic method (95.56-98.39% reduction). Power due to relative segment endpoint displacement in segmental power analyses is substantial and should be considered in analyzing energetic flow into and between segments. Copyright © 2017 Elsevier Ltd. All rights reserved.

  4. An Enhanced Islanding Microgrid Reactive Power, Imbalance Power, and Harmonic Power Sharing Scheme

    DEFF Research Database (Denmark)

    He, Jinwei; Lin, Yun Wei; Blaabjerg, Frede

    2015-01-01

    To address inaccurate power sharing problems in autonomous islanding microgrids, an enhanced droop control method through online virtual impedance adjustment is proposed. First, a term associated with DG reactive power, imbalance power, or harmonic power is added to the conventional real power......-frequency droop control. The transient real power variations caused by this term are captured to realize DG series virtual impedance tuning. With the regulation of DG virtual impedance at fundamental positive sequence, fundamental negative sequence, and harmonic frequencies, an accurate power sharing can...... unit local controllers. The feasibility of the proposed method is verified by simulated and experimental results from a low-power three-phase microgrid prototype....

  5. Dynamic Imbalance Analysis and Stability Control of Galloping Gait for a Passive Quadruped Robot

    OpenAIRE

    Chunlei Wang; Ting Zhang; Xiaohui Wei; Yongjun Long; Shigang Wang

    2015-01-01

    Some imbalance and balance postures of a passive quadruped robot with a simplified mathematical model are studied. Through analyzing the influence of the touchdown angle of the rear leg on the posture of the trunk during the flight phase, the stability criterion is concluded: the closer are the two moments which are the zero time of the pitching angle and the peak time of the center of mass, the better is the stability of the trunk posture during the flight phase. Additionally, the validity o...

  6. Blind I/Q imbalance compensation technique for direct-conversion digital radio transceivers

    CSIR Research Space (South Africa)

    De Witt, JJ

    2009-05-01

    Full Text Available in the compensated signal. It can adaptively be implemented and does not rely on block averaging, which enables imbalance tracking over time. An analysis is presented on the effect of noise, a frequency-selective channel, and a frequency offset between... and demodulator’s oscillators. Let the unwanted dc offset terms in the two signal paths be given by χI and χQ, and let a carrier leak-through component be given by ξ cos(ωct +∆ωt + θ + ρ). If the two matched low-pass filters are employed to remove the double...

  7. Effect of charge imbalance parameter on LEKW in ion-implanted quantum semiconductor plasmas

    Science.gov (United States)

    Chaudhary, Sandhya; Yadav, Nishchhal; Ghosh, S.

    2015-07-01

    In this study we present an analytical investigation on the propagation characteristics of electro-kinetic wave modified through quantum correction term and charge imbalance parameter using quantum hydrodynamic model for an ion-implanted semiconductor plasma. The dispersion relation has been analyzed in two distinct velocity regimes. We found that as the number of negative charges resides on the colloids increases, their role become increasing effective. The present investigation is important for understanding of wave and instability phenomena and can be put to various interesting applications.

  8. Sex Ratio Imbalances Among Children At Micro-Level: China And India Compared.

    OpenAIRE

    Guilmoto, Christophe,; Oliveau, Sébastien

    2007-01-01

    Sex ratio imbalances found in Asia are primarily due to the increasing proportions of sons among children in China and India: the level of gender discrimination in several regions of East China and Northwest India may be extremely pronounced and tends to display a high level of spatial concentration. Comparable data from the last censuses (2000, 2001) can be mapped at the local level, using counties (xian) for China and sub-district units (tahsil, taluk, etc.) for India. In this paper, we fir...

  9. An accurate autonomous islanding microgrid reactive power, imbalance power and harmonic power sharing scheme

    DEFF Research Database (Denmark)

    He, Jinwei; Li, Yun Wei; Blaabjerg, Frede

    2013-01-01

    To address inaccurate power sharing problems in autonomous islanding microgrids, an enhanced droop control method through adaptive virtual impedance adjustment is proposed. First, a term associated with DG reactive power, imbalance power or harmonic power is added to the conventional real power......-frequency droop control. The transient real power variations caused by this additional term are captured to realize DG series virtual impedance tuning. With the regulation of DG virtual impedance at fundamental positive sequence, fundamental negative sequence, and harmonic frequencies, an accurate power sharing...

  10. Widely Linear Equalization for IQ Imbalance and Skew Compensation in Optical Coherent Receivers

    DEFF Research Database (Denmark)

    Porto da Silva, Edson; Zibar, Darko

    2016-01-01

    In this paper, an alternative approach to design linear equalization algorithms for optical coherent receivers is introduced. Using widely linear complex analysis, a general analytical model it is shown, where In-phase/quadrature (IQ) imbalances and IQ skew at the coherent receiver front......, it is shown that, by applying the widely linear complex analysis, one can derive a complex-valued adaptive equalizer structure which is able to compensate for linear IQ-mixing effects at the receiver front-end. By extensive numerical simulations, the performance versus complexity of the proposed equalizer...

  11. Specific chromosomal imbalances in human papillomavirus-transfected cells during progression toward immortality

    Science.gov (United States)

    Solinas-Toldo, Sabina; Dürst, Matthias; Lichter, Peter

    1997-01-01

    High risk human papillomaviruses (HPVs) known to be closely associated with cervical cancer, such as HPV16 and HPV18, have the potential to immortalize human epithelial cells in culture. Four lines of HPV-transfected keratinocytes were analyzed by comparative genomic hybridization at different time points after transfection. A number of chromosomal imbalances was found to be highly characteristic for the cultures progressing toward immortality. Whereas several of these were new and previously not found as recurrent aberrations in cervical tumors, some were identical to chromosomal changes observed during cervical carcinogenesis. The data put new emphasis on the studied cell system as a relevant model for HPV-induced pathogenesis. PMID:9108068

  12. Cryptic genomic imbalances in patients with de novo or familial apparently balanced translocations and abnormal phenotype

    Directory of Open Access Journals (Sweden)

    Kanavakis Emanuel

    2008-07-01

    Full Text Available Abstract Background Carriers of apparently balanced translocations are usually phenotypically normal; however in about 6% of de novo cases, an abnormal phenotype is present. In the current study we investigated 12 patients, six de novo and six familial, with apparently balanced translocations and mental retardation and/or congenital malformations by applying 1 Mb resolution array-CGH. In all de novo cases, only the patient was a carrier of the translocation and had abnormal phenotype. In five out of the six familial cases, the phenotype of the patient was abnormal, although the karyotype appeared identical to other phenotypically normal carriers of the family. In the sixth familial case, all carriers of the translocations had an abnormal phenotype. Results Chromosomal and FISH analyses suggested that the rearrangements were "truly balanced" in all patients. However, array-CGH, revealed cryptic imbalances in three cases (3/12, 25%, two de novo (2/12, 33.3% and one familial (1/12, 16.6%. The nature and type of abnormalities differed among the cases. In the first case, what was identified as a de novo t(9;15(q31;q26.1, a complex rearrangement was revealed involving a ~6.1 Mb duplication on the long arm of chromosome 9, an ~10 Mb deletion and an inversion both on the long arm of chromosome 15. These imbalances were located near the translocation breakpoints. In the second case of a de novo t(4;9(q25;q21.2, an ~6.6 Mb deletion was identified on the short arm of chromosome 7 which is unrelated to the translocation. In the third case, of a familial, t(4;7(q13.3;p15.3, two deletions of ~4.3 Mb and ~2.3 Mb were found, each at one of the two translocation breakpoints. In the remaining cases the translocations appeared balanced at 1 Mb resolution. Conclusion This study investigated both de novo and familial apparently balanced translocations unlike other relatively large studies which are mainly focused on de novo cases. This study provides additional

  13. Evidence of redox imbalance in a patient with succinic semialdehyde dehydrogenase deficiency

    Directory of Open Access Journals (Sweden)

    Anna-Kaisa Niemi

    2014-01-01

    Full Text Available The pathophysiology of succinic semialdehyde dehydrogenase (SSADH deficiency is not completely understood. Oxidative stress, mitochondrial pathology, and low reduced glutathione levels have been demonstrated in mice, but no studies have been reported in humans. We report on a patient with SSADH deficiency in whom we found low levels of blood reduced glutathione (GSH, and elevations of dicarboxylic acids in urine, suggestive of possible redox imbalance and/or mitochondrial dysfunction. Thus, targeting the oxidative stress axis may be a potential therapeutic approach if our findings are confirmed in other patients.

  14. The odd one out: Revisiting and investigating the gender imbalance in ICT study choices

    Directory of Open Access Journals (Sweden)

    Scott Morton

    Full Text Available For the past two decades there has been an imbalance between male and female students entering the Bachelor of Information Technology degree from high schools. The literature suggests that only one in six students entering higher education to study computer related degrees are female. It also suggests that occupational stereotyping can be linked to the decline in the number of females entering computing degree courses. This research is proposing to revisit and investigate why this is still prevalent in today\\'s society that has been brought up on technology and can see the benefits of good careers and good jobs.

  15. Secretion imbalance between tumour necrosis factor and its inhibitor in inflammatory bowel disease

    OpenAIRE

    Noguchi, M; Hiwatashi, N; Liu, Z; Toyota, T

    1998-01-01

    Background—Tumour necrosis factor (TNF) α and TNF-β are soluble ligands binding to TNF receptors with similar activities; soluble TNF receptors neutralise TNF activity by acting as inhibitors. Little is known about the cytokine/soluble receptor role in inflammatory bowel disease (IBD). 
Aims—To test the hypothesis that an imbalance in secretion between TNF and TNF inhibitors plays a role in gut inflammation in patients with IBD. 
Methods—The secretion of TNF-α, TNF-β, and...

  16. A Novel DBC Layout for Current Imbalance Mitigation in SiC MOSFET Multichip Power Modules

    DEFF Research Database (Denmark)

    Li, Helong; Munk-Nielsen, Stig; Beczkowski, Szymon

    2016-01-01

    This paper proposes a novel Direct Bonded Copper (DBC) layout for mitigating the current imbalance among the paralleled SiC MOSFET dies in multichip power modules. Compared to the traditional layout, the proposed DBC layout significantly reduces the circuit mismatch and current coupling effect......, which consequently improves the current sharing among the paralleled SiC MOSFET dies in power module. Mathematic analysis and circuit model of the DBC layout are presented to elaborate on the superior features of the proposed DBC layout. Simulation and experimental results further verify the theoretical...

  17. A Novel DBC Layout for Current Imbalance Mitigation in SiC MOSFET Multichip Power Modules

    DEFF Research Database (Denmark)

    Li, Helong; Munk-Nielsen, Stig; Beczkowski, Szymon

    2016-01-01

    This letter proposes a novel direct bonded copper (DBC) layout for mitigating the current imbalance among the paralleled SiC MOSFET dies in multichip power modules. Compared to the traditional layout, the proposed DBC layout significantly reduces the circuit mismatch and current coupling effect......, which consequently improves the current sharing among the paralleled SiC MOSFET dies in power module. Mathematic analysis and circuit model of the DBC layout are presented to elaborate the superior features of the proposed DBC layout. Simulation and experimental results further verify the theoretical...

  18. Basic principles of electrolyte chemistry for microfluidic electrokinetics. Part II: Coupling between ion mobility, electrolysis, and acid-base equilibria.

    Science.gov (United States)

    Persat, Alexandre; Suss, Matthew E; Santiago, Juan G

    2009-09-07

    We present elements of electrolyte dynamics and electrochemistry relevant to microfluidic electrokinetics experiments. In Part I of this two-paper series, we presented a review and introduction to the fundamentals of acid-base chemistry. Here, we first summarize the coupling between acid-base equilibrium chemistry and electrophoretic mobilities of electrolytes, at both infinite and finite dilution. We then discuss the effects of electrode reactions on microfluidic electrokinetic experiments and derive a model for pH changes in microchip reservoirs during typical direct-current electrokinetic experiments. We present a model for the potential drop in typical microchip electrophoresis device. The latter includes finite element simulation to estimate the relative effects of channel and reservoir dimensions. Finally, we summarize effects of electrode and electrolyte characteristics on potential drop in microfluidic devices. As a whole, the discussions highlight the importance of the coupling between electromigration and electrophoresis, acid-base equilibria, and electrochemical reactions.

  19. Basic principles of electrolyte chemistry for microfluidic electrokinetics. Part I: Acid-base equilibria and pH buffers.

    Science.gov (United States)

    Persat, Alexandre; Chambers, Robert D; Santiago, Juan G

    2009-09-07

    We review fundamental and applied acid-base equilibrium chemistry useful to microfluidic electrokinetics. We present elements of acid-base equilibrium reactions and derive rules for pH calculation for simple buffers. We also present a general formulation to calculate pH of more complex, arbitrary mixtures of electrolytes, and discuss the effects of ionic strength and temperature on pH calculation. More practically, we offer advice on buffer preparation and on buffer reporting. We also discuss "real world" buffers and likely contamination sources. In particular, we discuss the effects of atmospheric carbon dioxide on buffer systems, namely, the increase in ionic strength and acidification of typical electrokinetic device buffers. In Part II of this two-paper series, we discuss the coupling of acid-base equilibria with electrolyte dynamics and electrochemistry in typical microfluidic electrokinetic systems.

  20. Acid-base balance of dairy cows and its relationship with alcoholic stability and mineral composition of milk

    Directory of Open Access Journals (Sweden)

    Rafael Fagnani

    2014-05-01

    Full Text Available This study aimed to associate the occurrence of acid-base disorders with the alcoholic stability of milk from animals in the field, and to evaluate differences between the mineral composition of milk that was both stable and unstable in alcohol. The sample comprised 96 dairy cows, where the milk and blood of each corresponding animal was collected. The mineral composition of stable and unstable milk in alcohol was different and may be related to acid-base disturbances. The average amount of phosphate was lower in the milk that was unstable in alcohol, while potassium was greater. Frequency of the alcoholically unstable milk cases was higher in the cows with acid-base disturbances. Respiratory alkalosis was the disorder that was most observed.

  1. The Acid-Base Balance Between Organic Acids and Circumneutral Ground Waters in Large Peatlands

    Science.gov (United States)

    Siegel, D. I.; Glaser, P. H.; So, J.

    2006-05-01

    Organic acids supply most of the acidity in the surface waters of bogs in peatlands. Yet, the fundamental geochemical properties of peatland organic acids are still poorly known. To assess the geochemical properties of typical organic acid assemblages in peatlands, we used a triprotic analog model for peat pore waters and surface waters in the Glacial Lake Agassiz Peatlands, optimizing on charge balance and calibrated to estimates of mole site density in DOC and triprotic acid dissociation constants. Before the calibration process, all bog waters and 76% of fen waters had more than +20% charge imbalance. After calibration, most electrochemically balanced within 20%. In the best calibration, the mole site denisty of bog DOC was estimated as ~0.05 mmol/mmol C., approximately 6 times smaller than that for fen DOC or the DOC in the fen deeper fen peats that underlie bogs. The three modeled de-protonation constants were; pKa1 = ~3.0, pKa2 = ~4.5 and pKa3 = ~7.0 for the bog DOC, and; pKa1 = ~5.2, pKa2 =~ 6.5 and pKa3 = ~7.0 for the fen DOC. Bog DOC, behaves as a strong acid despite its small mole site density. The DOC in bog runoff can therefore theoretically acidify the surface waters in adjacent fens wherever these waters do not receive sufficient buffering alkalinity from active groundwater seepage.

  2. Cupula-Inspired Hyaluronic Acid-Based Hydrogel Encapsulation to Form Biomimetic MEMS Flow Sensors.

    Science.gov (United States)

    Kottapalli, Ajay Giri Prakash; Bora, Meghali; Kanhere, Elgar; Asadnia, Mohsen; Miao, Jianmin; Triantafyllou, Michael S

    2017-07-28

    Blind cavefishes are known to detect objects through hydrodynamic vision enabled by arrays of biological flow sensors called neuromasts. This work demonstrates the development of a MEMS artificial neuromast sensor that features a 3D polymer hair cell that extends into the ambient flow. The hair cell is monolithically fabricated at the center of a 2 μm thick silicon membrane that is photo-patterned with a full-bridge bias circuit. Ambient flow variations exert a drag force on the hair cell, which causes a displacement of the sensing membrane. This in turn leads to the resistance imbalance in the bridge circuit generating a voltage output. Inspired by the biological neuromast, a biomimetic synthetic hydrogel cupula is incorporated on the hair cell. The morphology, swelling behavior, porosity and mechanical properties of the hyaluronic acid hydrogel are characterized through rheology and nanoindentation techniques. The sensitivity enhancement in the sensor output due to the material and mechanical contributions of the micro-porous hydrogel cupula is investigated through experiments.

  3. Evaluation of acid-base status in brain dead donors and the impact of metabolic acidosis on organ retrieval.

    Science.gov (United States)

    Lee, J H; Kim, M S; Na, S; Koh, S O; Sim, J; Choi, Y S

    2013-09-01

    Pathophysiologic changes after brain death can lead to acid-base disturbances. The primary aim of this study was to clarify the acid-base state and its source in brain dead donors using Stewart's approach. Additionally, we investigated whether the presence of metabolic acidosis affected the number of organs retrieved from donors. A retrospective review of electronic medical records was performed for brain dead donors who had undergone organ harvesting during the past 5 years in a tertiary medical center. The parameters related to acid-base disturbance and the number of organs retrieved from the donors was assessed. Sixty one brain dead donors were evaluated in this study. Twenty three (37.7%) of these patients had metabolic acidosis at the initial diagnosis of brain death. Metabolic acidosis resulted from hyperchloremia and a large strong ion gap. The severity of metabolic acidosis was masked by hypernatremia and hypoalbuminemia. In addition, donors without metabolic acidosis also showed mixed acid-base disturbances in which metabolic acidosis induced by significant hyperchloremia was combined with metabolic alkalosis caused by hypoalbuminemia and hypernatremia. Although more organs were retrieved from the donors without metabolic acidosis than those with metabolic acidosis (P=0.012), serum albumin level (P=0.010) and donor age (Pmetabolic acid-base disturbances, significantly correlated with the number of organs retrieved in multivariate regression analysis. Most brain dead donors exhibited metabolic acid-base disturbances. However, rather than metabolic acidosis, serum albumin level and donor age were well correlated with the number of organs retrieved.

  4. [Facial injections of hyaluronic acid-based fillers for malformations. Preliminary study regarding scar tissue improvement and cosmetic betterment].

    Science.gov (United States)

    Franchi, G; Neiva-Vaz, C; Picard, A; Vazquez, M-P

    2018-02-02

    Cross-linked hyaluronic acid-based fillers have gained rapid acceptance for treating facial wrinkles, deep tissue folds and sunken areas due to aging. This study evaluates, in addition to space-filling properties, their effects on softness and elasticity as a secondary effect, following injection of 3 commercially available cross-linked hyaluronic acid-based fillers (15mg/mL, 17,5mg/mL and 20mg/mL) in patients presenting with congenital or acquired facial malformations. We started injecting gels of cross-linked hyaluronic acid-based fillers in those cases in 2013; we performed 46 sessions of injections in 32 patients, aged from 13-32. Clinical assessment was performed by the patient himself and by a plastic surgeon, 15 days after injections and 6-18 months later. Cross-linked hyaluronic acid-based fillers offered very subtle cosmetic results and supplemented surgery with a very high level of satisfaction of the patients. When injected in fibrosis, the first session enhanced softness and elasticity; the second session enhanced the volume. Cross-linked hyaluronic acid-based fillers fill sunken areas and better softness and elasticity of scar tissues. In addition to their well-understood space-filling function, as a secondary effect, the authors demonstrate that cross-linked hyaluronic acid-based fillers improve softness and elasticity of scarring tissues. Many experimental studies support our observations, showing that cross-linked hyaluronic acid stimulates the production of several extra-cellular matrix components, including dermal collagen and elastin. Copyright © 2018 Elsevier Masson SAS. All rights reserved.

  5. Medical Devices; Immunology and Microbiology Devices; Classification of the Streptococcus SPP. Nucleic Acid-Based Assay. Final order.

    Science.gov (United States)

    2017-10-30

    The Food and Drug Administration (FDA or we) is classifying the Streptococcus spp. nucleic acid-based assay into class II (special controls). The special controls that apply to the device type are identified in this order and will be part of the codified language for the Streptococcus spp. nucleic acid-based assay's classification. We are taking this action because we have determined that classifying the device into class II (special controls) will provide a reasonable assurance of safety and effectiveness of the device. We believe this action will also enhance patients' access to beneficial innovative devices, in part by reducing regulatory burdens.

  6. Acid-base balance disturbances in plasma exchange depend on the replacement fluid used.

    Science.gov (United States)

    Cid, Joan; Carbassé, Gloria; Gamir, Montse; Jiménez, María; Arellano-Rodrigo, Eduardo; Lozano, Miguel

    2015-11-01

    Metabolic alkalosis occurs as a direct result of plasma exchange (PE) because of metabolism of citrate. However, we observed a decrease of serum pH and bicarbonate after PE when albumin was used as replacement fluid. The acid-base balance in 2730 PEs using different replacement fluids (albumin, fresh-frozen plasma [FFP], or both) was measured, and absolute changes (Δ) in acid-base balance were compared. The frequency of adverse effects (AEs) before and after using prophylactic administration of sodium bicarbonate was compared. A decrease of serum pH and bicarbonate was observed after PEs when albumin was used as replacement fluid (Δ pH = -0.06 ± 0.04; Δ bicarbonate = -4.03 ± 2.29 mmol/L; Δ base excess = -2.54 ± 3.82 mmol/L). An increase of serum pH and bicarbonate was observed after PEs when FFP was used as replacement fluid (Δ pH = +0.04 ± 0.05; Δ bicarbonate = +3.6 ± 3.68 mmol/L; Δ base excess = +1.62 ± 4.51 mmol/L). The prophylactic administration of sodium bicarbonate corrected partially the decrease of serum pH and bicarbonate after finishing PEs when albumin was used as replacement fluid (Δ pH = -0.04 ± 0.04; Δ bicarbonate = -3.1 ± 2.47 mmol/L; Δ base excess = -3.35 ± 3.06 mmol/L). The frequency of AEs after using prophylactic administration of sodium bicarbonate was lower in comparison with the frequency of AEs before using prophylactic administration of sodium bicarbonate (2.0% vs. 4.8%; p < 0.001). A decrease of serum pH and bicarbonate appeared in patients after PEs when albumin was used as replacement fluid; it was corrected partially with prophylactic administration of sodium bicarbonate, and it was associated with fewer AEs. © 2015 AABB.

  7. Comparative bioavailability studies of citric acid and malonic acid based aspirin effervescent tablets

    Directory of Open Access Journals (Sweden)

    Anju Gauniya

    2010-01-01

    Full Text Available Purpose: The present investigation is aimed at comparing the pharmacokinetic profile (Bioavailability of aspirin in tablet formulations, which were prepared by using different effervescent excipients such as citric acid and malonic acid. Materials and Methods: The relative bioavailability and pharmacokinetics of citric acid based aspirin effervescent tablet (Product A and malonic acid based aspirin effervescent tablet (Product B formulations were evaluated for an in-vitro dissolution study and in-vivo bioavailability study, in 10 normal healthy rabbits. The study utilized a randomized, crossover design with a one-week washout period between doses. Blood samples were collected at 0, 1, 2, 4, 6, 8, 12 and 24 hours following a 100 mg/kg dose. Plasma samples were assayed by High Performance Liquid Chromatography. T max , C max , AUC 0-24 , AUC 0- ∞, MRT, K a, and relative bioavailability were estimated using the traditional pharmacokinetic methods and were compared by using the paired t-test. Result: In the present study, Products A and B showed their T max , C max , AUC 0-24 , AUC 0- ∞, MRT, and K a values as 2.5 h, 2589 ± 54.79 ng/ml, 9623 ± 112.87 ng.h/ml, 9586 ± 126.22 ng.h/ml, 3.6 ± 0.10 h, and 0.3698 ± 0.003 h -1 for Product A and 3.0 h, 2054 ± 55.79 ng/ml, 9637 ± 132.87 ng.h/ml, 9870 ± 129.22 ng.h/ml, 4.76 ± 0.10 h, and 0.3812 ± 0.002 h -1 for Product B, respectively. Conclusion: The results of the paired t-test of pharmacokinetics data showed that there was no significant difference between Products A and B. From both the in vitro dissolution studies and in vivo bioavailability studies it was concluded that products A and B had similar bioavailability.

  8. Variability of Acid-Base Status in Acetate-Free Biofiltration 84% versus Bicarbonate Dialysis

    Directory of Open Access Journals (Sweden)

    Harzallah Kais

    2008-01-01

    Full Text Available The ultimate goal of hemodialysis (HD treatment is to achieve the highest level of efficacy in the presence of maximal clinical tolerance. With an aim to offer good hemodynamic stability, as observed during the acetate-free biofiltration 14% (AFB 14% to patients who are intolerant to bicarbonate dialysis (BD and with less cost, we have developed since June 1994, a new HD technique, namely AFB 84%. This study was carried out to analyze acid-base variations during the AFB 84% in comparison to BD in hemodynamically stable patients on regular HD. This was a prospective randomized crossover study carried out on 12 patients (6 males and 6 females for a total of 144 HD sessions (72 BD and 72 AFB 84%. Patients with decompensated cardiomyopathy, respiratory diseases or uncontrolled hypertension were not included in the trial. All the patients were treated with BD or AFB 84%; the latter is characterized by the absence of acetate in the dialysate and a complete correction of buffer balance by post-dilutional infusion of bicarbonate-based replacement solution. The comparison of pre-dialysis arterial acid-base and blood-gas parameters revealed no significant differences of pH, HCO 3 - and paCO 2 levels between the two techniques. Analysis of post-dialysis parameters showed that, among patients dialyzed with BD, there was over correction of metabolic acidosis with a tendency towards metabolic alkalosis. In contrast, in patients dialyzed with AFB 84%, we observed a significant improvement in pH and HCO 3 - levels but the increase in paCO2 level was not significant. A comparison of these parameters between the two techniques showed statistically significant difference in pH, HCO3 - and paCO2 levels, but not for paO2 level. AFB 84% can offer some important advantages with the complete absence of acetate from the substitution fluids, and permits a better correction of metabolic acidosis than BD, without causing alkalosis.

  9. Comparative bioavailability studies of citric acid and malonic acid based aspirin effervescent tablets.

    Science.gov (United States)

    Gauniya, Anju; Das, Sanjita; Mallick, Subrata; Basu, S P

    2010-04-01

    The present investigation is aimed at comparing the pharmacokinetic profile (Bioavailability) of aspirin in tablet formulations, which were prepared by using different effervescent excipients such as citric acid and malonic acid. The relative bioavailability and pharmacokinetics of citric acid based aspirin effervescent tablet (Product A) and malonic acid based aspirin effervescent tablet (Product B) formulations were evaluated for an in-vitro dissolution study and in-vivo bioavailability study, in 10 normal healthy rabbits. The study utilized a randomized, crossover design with a one-week washout period between doses. Blood samples were collected at 0, 1, 2, 4, 6, 8, 12 and 24 hours following a 100 mg/kg dose. Plasma samples were assayed by High Performance Liquid Chromatography. T(max), C(max), AUC(0-24), AUC(0- ∞,) MRT, K(a,) and relative bioavailability were estimated using the traditional pharmacokinetic methods and were compared by using the paired t-test. In the present study, Products A and B showed their T(max), C(max), AUC(0-24), AUC(0- ∞,) MRT, and K(a) values as 2.5 h, 2589 ± 54.79 ng/ml, 9623 ± 112.87 ng.h/ml, 9586 ± 126.22 ng.h/ml, 3.6 ± 0.10 h, and 0.3698 ± 0.003 h (-1) for Product A and 3.0 h, 2054 ± 55.79 ng/ml, 9637 ± 132.87 ng.h/ml, 9870 ± 129.22 ng.h/ml, 4.76 ± 0.10 h, and 0.3812 ± 0.002 h (-1) for Product B, respectively. The results of the paired t-test of pharmacokinetics data showed that there was no significant difference between Products A and B. From both the in vitro dissolution studies and in vivo bioavailability studies it was concluded that products A and B had similar bioavailability.

  10. Selecting the Optimal Combination Model of FSSVM for the Imbalance Datasets

    Directory of Open Access Journals (Sweden)

    Chuandong Qin

    2014-01-01

    Full Text Available Imbalanced data learning is one of the most active and important fields in machine learning research. The existing class imbalance learning methods can make Support Vector Machines (SVMs less sensitive to class imbalance; they still suffer from the disturbance of outliers and noise present in the datasets. A kind of Fuzzy Smooth Support Vector Machines (FSSVMs are proposed based on the Smooth Support Vector Machine (SSVM of O. L. Mangasarian. SSVM can be computed by the Broyden-Fletcher-Goldfarb-Shanno (BFGS algorithm or the Newton-Armijo algorithm easily. Two kinds of fuzzy memberships and three smooth functions can be chosen in the algorithms. The fuzzy memberships consider the contribution rate of each sample to the optimal separating hyperplane. The polynomial smooth functions can make the optimization problem more accurate at the inflection point. Those changes play the active effects on trials. The results of the experiments show that the FSSVMs can gain the better accuracy and the shorter time than the SSVMs and some of the other methods.

  11. A Dynamic Ensemble Framework for Mining Textual Streams with Class Imbalance

    Directory of Open Access Journals (Sweden)

    Ge Song

    2014-01-01

    Full Text Available Textual stream classification has become a realistic and challenging issue since large-scale, high-dimensional, and non-stationary streams with class imbalance have been widely used in various real-life applications. According to the characters of textual streams, it is technically difficult to deal with the classification of textual stream, especially in imbalanced environment. In this paper, we propose a new ensemble framework, clustering forest, for learning from the textual imbalanced stream with concept drift (CFIM. The CFIM is based on ensemble learning by integrating a set of clustering trees (CTs. An adaptive selection method, which flexibly chooses the useful CTs by the property of the stream, is presented in CFIM. In particular, to deal with the problem of class imbalance, we collect and reuse both rare-class instances and misclassified instances from the historical chunks. Compared to most existing approaches, it is worth pointing out that our approach assumes that both majority class and rareclass may suffer from concept drift. Thus the distribution of resampled instances is similar to the current concept. The effectiveness of CFIM is examined in five real-world textual streams under an imbalanced nonstationary environment. Experimental results demonstrate that CFIM achieves better performance than four state-of-the-art ensemble models.

  12. Imbalance in the sensitivity to different types of rewards in pathological gambling.

    Science.gov (United States)

    Sescousse, Guillaume; Barbalat, Guillaume; Domenech, Philippe; Dreher, Jean-Claude

    2013-08-01

    Pathological gambling is an addictive disorder characterized by a persistent and compulsive desire to engage in gambling activities. This maladaptive behaviour has been suggested to result from a decreased sensitivity to experienced rewards, regardless of reward type. Alternatively, pathological gambling might reflect an imbalance in the sensitivity to monetary versus non-monetary incentives. To directly test these two hypotheses, we examined how the brain reward circuit of pathological gamblers responds to different types of rewards. Using functional magnetic resonance imaging, we compared the brain responses of 18 pathological gamblers and 20 healthy control subjects while they engaged in a simple incentive task manipulating both monetary and visual erotic rewards. During reward anticipation, the ventral striatum of pathological gamblers showed a differential response to monetary versus erotic cues, essentially driven by a blunted reactivity to cues predicting erotic stimuli. This differential response correlated with the severity of gambling symptoms and was paralleled by a reduced behavioural motivation for erotic rewards. During reward outcome, a posterior orbitofrontal cortex region, responding to erotic rewards in both groups, was further recruited by monetary gains in pathological gamblers but not in control subjects. Moreover, while ventral striatal activity correlated with subjective ratings assigned to monetary and erotic rewards in control subjects, it only correlated with erotic ratings in gamblers. Our results point to a differential sensitivity to monetary versus non-monetary rewards in pathological gambling, both at the motivational and hedonic levels. Such an imbalance might create a bias towards monetary rewards, potentially promoting addictive gambling behaviour.

  13. Trade integration and trade imbalances in the European Union: a network perspective.

    Directory of Open Access Journals (Sweden)

    Gautier M Krings

    Full Text Available We study the ever more integrated and ever more unbalanced trade relationships between European countries. To better capture the complexity of economic networks, we propose two global measures that assess the trade integration and the trade imbalances of the European countries. These measures are the network (or indirect counterparts to traditional (or direct measures such as the trade-to-GDP (Gross Domestic Product and trade deficit-to-GDP ratios. Our indirect tools account for the European inter-country trade structure and follow (i a decomposition of the global trade flow into elementary flows that highlight the long-range dependencies between exporting and importing economies and (ii the commute-time distance for trade integration, which measures the impact of a perturbation in the economy of a country on another country, possibly through intermediate partners by domino effect. Our application addresses the impact of the launch of the Euro. We find that the indirect imbalance measures better identify the countries ultimately bearing deficits and surpluses, by neutralizing the impact of trade transit countries, such as the Netherlands. Among others, we find that ultimate surpluses of Germany are quite concentrated in only three partners. We also show that for some countries, the direct and indirect measures of trade integration diverge, thereby revealing that these countries (e.g. Greece and Portugal trade to a smaller extent with countries considered as central in the European Union network.

  14. Coenzyme Q10 and oxidative imbalance in Down syndrome: biochemical and clinical aspects.

    Science.gov (United States)

    Tiano, L; Padella, L; Carnevali, P; Gabrielli, O; Bruge, F; Principi, F; Littarru, G P

    2008-01-01

    Down syndrome (DS) is a chromosomal abnormality (trisomy 21) associated with mental retardation and Alzheimer-like dementia, characteristic change of the individual's phenotype and premature ageing. Oxidative stress is known to play a major role in this pathology since a gene dose effect leads to elevated ratio of superoxide dismutase to catalase/glutathione peroxidase compared to controls in all age categories suggesting that oxidative imbalance contributes to the clinical manifestation of DS. Hyperuricemia is another feature of DS that has an interesting relationship with oxidative stress since uric acid represents an important free radical scavenger. However its formation is connected to the conversion of Xanthine dehydrogenase (XDH) to Xanthine oxidase (XO) which leads to concomitant production of free radicals. Here we report that plasma samples from DS patients in pediatric age, despite an increased total antioxidant capacity, largely due to elevated Uric acid content (UA), present significantly elevated markers of oxidative damage such as increased allantoin levels. Moreover DS plasma samples do not differ from healthy control ones in terms of Coenzyme Q10 and susceptibility to peroxidative stimuli. On the contrary, lymphocyte and platelet CoQ10 content was significantly lower in DS patients, a fact that might underlie oxidative imbalance at a cellular level.

  15. A Compact QPSK Modulator with Low Amplitude and Phase Imbalance for Remote Sensing Applications

    KAUST Repository

    Ghaffar, Farhan Abdul

    2012-09-30

    A new, compact and wide-band Quadrature Phase Shift Keying (QPSK) modulator is presented for remote sensing applications. The microstrip-based modulator employs quadrature hybrid coupler, Wilkinson divider, rat race coupler and GaAs MESFET switches. It is designed to be part of an X band remote sensing transmitter with a center frequency of 8.25GHz. The fabricated module demonstrates the lowest reported amplitude and phase imbalances (0.1dB and 0.4° respectively) around its center frequency. The modulation, tested up to 160 Mbps data rate, displays carrier suppression greater than 30 dB. With negligible DC power consumption and low insertion loss, it operates for a wide bandwidth of 3 GHz (7-10 GHz). The effect of amplitude and phase imbalance is investigated on the performance of the modulator. Finally, a transmitter employing this modulator exhibits an excellent overall Error Vector Magnitude (EVM) of around 8 % that is considerably low as compared to the typically obtained values for such transmitters.

  16. Clinical analysis of electrolyte imbalance in thalamic hemorrhage patients within 24 h after admission.

    Science.gov (United States)

    Guo, Zhenwei; Wang, Tianzhu; Zhang, John H; Qin, Xinyue

    2011-01-01

    We have observed that patients with thalamic hemorrhage are more likely to have electrolyte disturbances than those with non-thalamic hemorrhage. Here, we are attempting to provide some comprehensive information on electrolyte disturbances in patients with thalamic hemorrhage. Retrospectively, 67 patients with thalamic hemorrhage (TH group) and 256 with non-thalamic hemorrhage (N-TH group) were found from computer tomography images. Electrolytes of these patients were tested within 24 h after hospitalization. Chi-square test was used to compare the incidence of electrolyte imbalance. Serum K+ levels were found to be abnormal in 37.31% of the patients in the TH group and 24.21% in the N-TH group, and the difference was significant (pelectrolyte disturbances (42.50%) was higher than that of patients with normal electrolyte levels (14.81%, pelectrolyte imbalance is higher in patients with thalamic hemorrhage than in those with non-thalamic hemorrhage. The reason may be partly related to the location of the hemorrhage. Electrolyte disturbance may contribute to the higher mortality of patients with thalamic hemorrhage.

  17. [AUTONOMIC NERVOUS SYSTEM AND ITS IMBALANCE IN NEURO INTENSIVE CARE UNIT].

    Science.gov (United States)

    Popugaev, K A; Lubnin, A Yu; Zabelin, M V; Samoylov, A S

    2016-01-01

    The autonomic nervous system (ANS) provides homeostasis due to the innervation of the secretory glands, smooth muscle and cardiac muscle. Higher centers of the ANS (primarily the hypothalamus, some centers of the brain stem and limbic system) form a integrative network, which plays a key role in coordinating the functioning of the endocrine, immune system and other parts of the central nervous system. Intracranial centers of the ANS are responsible for the consciousness, behavioral, emotional, and other components of the higher nervous activity. Thus, the significance of the ANS can't be overestimated. At the same time today in neurointensive care there are no clear criteria for ANS dysfunction, we don't have universally recognized monitoring facilities for ANS and approaches to targeted therapy of its disorders. This paradox is even more important as in the pathogenesis of some critical conditions such as neurogenic pulmonary edema, stunned myocardium, cardiomyopathy Takotsubo lies precisely ANS imbalance. This review devoted to the ANS and some problems associated with its imbalance.

  18. Differential alteration of lipid antigen presentation to NKT cells due to imbalances in lipid metabolism.

    Science.gov (United States)

    Schümann, Jens; Facciotti, Federica; Panza, Luigi; Michieletti, Mario; Compostella, Federica; Collmann, Anthony; Mori, Lucia; De Libero, Gennaro

    2007-06-01

    Deficiencies in enzymes of the lysosomal glycosphingolipid degradation pathway or in lysosomal lipid transfer proteins cause an imbalance in lipid metabolism and induce accumulation of certain lipids. A possible impact of such an imbalance on the presentation of lipid antigens to lipid-reactive T cells has only been hypothesized but not extensively studied so far. Here we demonstrate that presentation of lipid antigens to, and development of, lipid-reactive CD1d-restricted NKT cells, are impaired in mice deficient in the lysosomal enzyme beta-galactosidase (betaGal) or the lysosomal lipid transfer protein Niemann-Pick C (NPC) 2. Importantly, the residual populations of NKT cells selected in betaGal-/- and NPC2-/- mice showed differential TCR and CD4 repertoire characteristics, suggesting that differential selecting CD1d:lipid antigen complexes are formed. Furthermore, we provide direct evidence that accumulation of lipids impairs lipid antigen presentation in both cases. However, the mechanisms by which imbalanced lipid metabolism affected lipid antigen presentation were different. Based on these results, the impact of lipid accumulation should be generally considered in the interpretation of immunological deficiencies found in mice suffering from lipid metabolic disorders.

  19. Gene dosage imbalance during DNA replication controls bacterial cell-fate decision

    Science.gov (United States)

    Igoshin, Oleg

    Genes encoding proteins in a common regulatory network are frequently located close to one another on the chromosome to facilitate co-regulation or couple gene expression to growth rate. Contrasting with these observations, here we demonstrate a functional role for the arrangement of Bacillus subtilis sporulation network genes on opposite sides of the chromosome. We show that the arrangement of two sporulation network genes, one located close to the origin, the other close to the terminus leads to a transient gene dosage imbalance during chromosome replication. This imbalance is detected by the sporulation network to produce cell-cycle coordinated pulses of the sporulation master regulator Spo0A~P. This pulsed response allows cells to decide between sporulation and continued vegetative growth during each cell-cycle spent in starvation. Furthermore, changes in DNA replication and cell-cycle parameters with decreased growth rate in starvation conditions enable cells to indirectly detect starvation without the need for evaluating specific metabolites. The simplicity of the uncovered coordination mechanism and starvation sensing suggests that it may be widely applicable in a variety of gene regulatory and stress-response settings. This work is supported by National Science Foundation Grants MCB-1244135, EAGER-1450867, MCB-1244423, NIH NIGMS Grant R01 GM088428 and HHMI International Student Fellowship.

  20. Cardiac autonomic imbalance by social stress in rodents: understanding putative biomarkers

    Directory of Open Access Journals (Sweden)

    Susan K Wood, Phd

    2014-08-01

    Full Text Available Exposure to stress or traumatic events can lead to the development of depression and anxiety disorders. In addition to the debilitating consequences on mental health, patients with psychiatric disorders also suffer from autonomic imbalance, making them susceptible to a variety of medical disorders. Emerging evidence utilizing spectral analysis of heart rate variability (HRV, a reliable noninvasive measure of cardiovascular autonomic regulation, indicates that patients with depression and various anxiety disorders (i.e., panic, social, generalized anxiety disorders, and post traumatic stress disorder are characterized by decreased HRV. Social stressors in rodents are ethologically relevant experimental stressors that recapitulate many of the dysfunctional behavioral and physiological changes that occur in psychological disorders. In this review, evidence from clinical studies and preclinical stress models identify putative biomarkers capable of precipitating the comorbidity between disorders of the mind and autonomic dysfunction. Specifically, the role of corticotropin releasing factor, neuropeptide Y and inflammation are investigated. The impetus for this review is to highlight stress-related biomarkers that may prove critical in the development of autonomic imbalance in stress -related psychiatric disorders.