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Monosegemented flow potentiometric titration for the determination of chloride in milk and wine
Vieira, Jonas A.;Raimundo Jr., Ivo M.;Reis, Boaventura F.;Montenegro, M. Concei??o B.S.M.;Araújo, Alberto N.;
Journal of the Brazilian Chemical Society , 2003, DOI: 10.1590/S0103-50532003000200012
Abstract: an automated flow potentiometric titration procedure for the determination of chloride in milk and wine exploiting the monosegmented flow approach is described. the flow network was designed based on a six-way solenoid valve, controlled by a microcomputer running software written in visualbasic 3.0, allowing selection of the titration conditions. an ag2s tubular electrode selective for cl- and a conventional ag/agcl electrode were employed as indicator and reference, respectively. an algorithm based on the potential difference between two subsequent titrant additions was developed, allowing to reach the end point in less than 10 attempts, with a precision better than 1.0%. the proposed system was evaluated by determining chloride in milk and wine, using a standard agno3 solution as titrant. accuracy was ascertained by comparing the results with those obtained using the aoac procedure. no significant difference at a 95% confidence level was observed.
Monosegemented flow potentiometric titration for the determination of chloride in milk and wine  [cached]
Vieira Jonas A.,Raimundo Jr. Ivo M.,Reis Boaventura F.,Montenegro M. Concei??o B.S.M.
Journal of the Brazilian Chemical Society , 2003,
Abstract: An automated flow potentiometric titration procedure for the determination of chloride in milk and wine exploiting the monosegmented flow approach is described. The flow network was designed based on a six-way solenoid valve, controlled by a microcomputer running software written in VisualBasic 3.0, allowing selection of the titration conditions. An Ag2S tubular electrode selective for Cl- and a conventional Ag/AgCl electrode were employed as indicator and reference, respectively. An algorithm based on the potential difference between two subsequent titrant additions was developed, allowing to reach the end point in less than 10 attempts, with a precision better than 1.0%. The proposed system was evaluated by determining chloride in milk and wine, using a standard AgNO3 solution as titrant. Accuracy was ascertained by comparing the results with those obtained using the AOAC procedure. No significant difference at a 95% confidence level was observed.
Efficacy of positive end-expiratory pressure titration after the alveolar recruitment manoeuvre in patients with acute respiratory distress syndrome
Jin Huh, Hoon Jung, Hye Choi, Sang-Bum Hong, Chae-Man Lim, Younsuck Koh
Critical Care , 2009, DOI: 10.1186/cc7725
Abstract: Fifty-seven patients with early ARDS were randomly assigned to a group given decremental PEEP titration following ARM or a table-based PEEP (control) group. PEEP and inspired fraction of oxygen (FiO2) in the control group were set according to the table-based combinations of FiO2 and PEEP of the ARDS network, by which we aimed to achieve a PEEP level compatible with an oxygenation target. In the decremental PEEP titration group, the oxygen saturation and static compliance were monitored as the patients performed the ARM along with the extended sigh method, which is designed to gradually apply and withdraw a high distending pressure over a prolonged period, and the decremental titration of PEEP.The baseline characteristics did not differ significantly between the control and decremental PEEP titration groups. Initial oxygenation improved more in the decremental PEEP titration group than in the control group. However, dynamic compliance, tidal volume and PEEP were similar in the two groups during the first week. The duration of use of paralysing or sedative agents, mechanical ventilation, stay in the intensive care unit and mortality at 28 days did not differ significantly between the decremental PEEP titration and control groups.The daily decremental PEEP titration after ARM showed only initial oxygenation improvement compared with the table-based PEEP method. Respiratory mechanics and patient outcomes did not differ between the decremental PEEP titration and control groups.ClinicalTrials.gov identifier: ISRCTN79027921.Two recent randomised controlled trials involving patients with acute lung injury (ALI) or acute respiratory distress syndrome (ARDS) demonstrated that mortality can be reduced significantly by setting a low tidal volume (VT) [1] and by setting both a low VT and adequate positive end-expiratory pressure (PEEP) levels titrated by pressure-volume curves [2,3]. However, this strategy favours further lung collapse or derecruitment, especially when used wit
Gastric intramucosal pH is stable during titration of positive end-expiratory pressure to improve oxygenation in acute respiratory distress syndrome
Ibrahim Akinci, Nahit ?akar, G?khan Mutlu, Simru Tugrul, Perihan Ergin Ozcan, Musa Gitmez, Figen Esen, Lutfi Telci
Critical Care , 2003, DOI: 10.1186/cc2172
Abstract: Gastric mucosal pH was measured using gastric tonometry at all levels of PEEP. The thermodilution technique was used for measurement of cardiac index. Gastric mucosal pH was similar at baseline and at optimal PEEP levels, but it was slightly reduced at maximum PEEP. Cardiac index and oxygen delivery remained stable at all PEEP levels.Incremental titration of PEEP based on improvement in oxygenation does not decrease gastric intramucosal perfusion when cardiac output is preserved in patients with ARDS.Positive end-expiratory pressure (PEEP) is an important component of the ventilatory management of acute lung injury (ALI) and acute respiratory distress syndrome (ARDS). PEEP improves oxygenation by redistributing the alveolar fluid and restores functional residual capacity by keeping the alveoli open. However, PEEP can be detrimental because it may, particularly at high levels, decrease cardiac output by decreasing the venous return as a result of diminished pressure gradient between the systemic veins and right atrium [1], and consequently it may lead to hypoperfusion of vital organs. Ultimately, despite improving arterial oxygen content, PEEP may decrease oxygen delivery to various organs, among which the splanchnic vascular bed appears to be particularly at risk because of its predisposing features and the influence of PEEP on regional blood flow distribution.Maintenance of splanchnic blood flow is important because splanchnic hypoperfusion may play a critical role in the pathogenesis of multiorgan dysfunction syndrome [2,3]. Mechanical ventilation has been suggested to potentiate the adverse effects of underlying critical illness on splanchnic vasculature and contribute to the development of multiorgan dysfunction syndrome, particularly when 'injurious' ventilatory strategies that produce high end-inspiratory lung volumes are employed [3]. Experimental studies suggested that mechanical ventilation with considerably high levels of PEEP can lead to splanchnic hypope
Respiratory and haemodynamic changes during decremental open lung positive end-expiratory pressure titration in patients with acute respiratory distress syndrome
Christian Gernoth, Gerhard Wagner, Paolo Pelosi, Thomas Luecke
Critical Care , 2009, DOI: 10.1186/cc7786
Abstract: A software programme (Open Lung Tool?) incorporated into a standard ventilator controlled the recruitment (pressure-controlled ventilation with fixed PEEP at 20 cmH2O and increased driving pressures at 20, 25 and 30 cmH2O for two minutes each) and PEEP titration (PEEP lowered by 2 cmH2O every two minutes, with tidal volume set at 6 ml/kg). The open lung PEEP (OL-PEEP) was defined as the PEEP level yielding maximum dynamic respiratory compliance plus 2 cmH2O. Gas exchange, respiratory mechanics and central haemodynamics using the Pulse Contour Cardiac Output Monitor (PiCCO?), as well as transoesophageal echocardiography were measured at the following steps: at baseline (T0); during the final recruitment step with PEEP at 20 cmH2O and driving pressure at 30 cmH2O, (T20/30); at OL-PEEP, following another recruitment manoeuvre (TOLP).The ratio of partial pressure of arterial oxygen (PaO2) to fraction of inspired oxygen (FiO2) increased from T0 to TOLP (120 ± 59 versus 146 ± 64 mmHg, P < 0.005), as did dynamic respiratory compliance (23 ± 5 versus 27 ± 6 ml/cmH2O, P < 0.005). At constant PEEP (14 ± 3 cmH2O) and tidal volumes, peak inspiratory pressure decreased (32 ± 3 versus 29 ± 3 cmH2O, P < 0.005), although partial pressure of arterial carbon dioxide (PaCO2) was unchanged (58 ± 22 versus 53 ± 18 mmHg). No significant decrease in mean arterial pressure, stroke volume or cardiac output occurred during the recruitment (T20/30). However, left ventricular end-diastolic area decreased at T20/30 due to a decrease in the left ventricular end-diastolic septal-lateral diameter, while right ventricular end-diastolic area increased. Right ventricular function, estimated by the right ventricular Tei-index, deteriorated during the recruitment manoeuvre, but improved at TOLP.A standardised open lung strategy increased oxygenation and improved respiratory system compliance. No major haemodynamic compromise was observed, although the increase in right ventricular Tei-index and right v
Quantum Evolution and Anticipation  [PDF]
Hans-Rudolf Thomann
Physics , 2010,
Abstract: In a previous paper we have investigated quantum states evolving into mutually orthogonal states at equidistant times, and the quantum anticipation effect exhibited by measurements at one half step. Here we extend our analyzes of quantum anticipation to general type quantum evolutions and spectral measures and prove that quantum evolutions possessing an embedded orthogonal evolution are characterized by positive joint spectral measure. Furthermore, we categorize quantum evolution, assess anticipation strength and provide a framework of analytic tools and results, thus preparing for further investigation and experimental verification of anticipation in concrete physical situations such as the H-atom, which we have found to exhibit anticipation.
Recruitment maneuvers and positive end-expiratory pressure/tidal ventilation titration in acute lung injury/acute respiratory distress syndrome: translating experimental results to clinical practice
Carmen Barbas, Gustavo de Mattos, Eduardo Borges
Critical Care , 2005, DOI: 10.1186/cc3800
Abstract: It is well known that the main phenomenon of hypoxemia in acute lung injury/acute respiratory distress syndrome (ALI/ARDS) is the high shunt fraction caused by the nonaerated areas of the lungs. During the disease process, the volume of extravascular lung water and the lung weight increase and promote the collapse of peripheral airways and lung parenchyma, mainly in the gravitation-dependent lung regions (Fig. 1). This phenomenon can be exacerbated by anesthesia and conditions of chest wall impairment. The relationship between the nonaerated, poorly aerated, normally aerated and hyperinflated lung regions depends on the degree of heterogeneity of the ALI/ARDS and the net result of the interaction of the pressure applied to the lung parenchyma (airway pressure/end expiratory pressure) and chest wall mechanics, as illustrated in the report by Henzler and colleagues [1] appearing in this issue of Critical Care. The most important force is not the airway pressure or tidal volume itself but the stress and strain that this airway pressure/tidal volume generates and the duration of these stresses and strains. At the bedside, the rough equivalent of stress is transpulmonary pressure, and the rough equivalent of the strain is tidal volume/end expiratory lung volume [2].This modern and complex mechanical ventilatory approach of ALI/ARDS recruitment maneuvers and positive end-expiratory pressure (PEEP)/tidal ventilation titration is a meshwork of interdependent but heterogeneously affected lung subunits that are behave according to different and multiple pressure–volume envelopes of the respiratory system during mechanical ventilation, which in some cases can be represented by respiratory mechanics (depending on the heterogeneity and etiology of the ALI/ARDS and the net results of the mechanical configuration of the respiratory system and the applied inspiratory/expiratory pressure along the mechanical ventilatory support duration) [3]. In 1998, a Brazilian prospective, random
Quantum Anticipation Explorer  [PDF]
Hans-Rudolf Thomann
Computer Science , 2011,
Abstract: Quantum anticipation explorer is a computer program allowing the numerical exploration of quantum anticipation which has been analyzed in arXiv:0810.183v1 and arXiv:1003.1090v1 for H-Atom, equidistant, random and custom spectra. This tool determines the anticipation strength at those times orthogonal evolution is possible. This paper is the user's guide explaining its capabilities, installation and usage, and documenting the mathematics and algorithms implemented in the software. A zip file containing the setup and documentation can be downloaded from http://www.thomannconsulting.ch/public/aboutus/aboutus-en.htm free of cost.
Palatable Meal Anticipation in Mice  [PDF]
Cynthia T. Hsu,Danica F. Patton,Ralph E. Mistlberger,Andrew D. Steele
PLOS ONE , 2012, DOI: 10.1371/journal.pone.0012903
Abstract: The ability to sense time and anticipate events is a critical skill in nature. Most efforts to understand the neural and molecular mechanisms of anticipatory behavior in rodents rely on daily restricted food access, which induces a robust increase of locomotor activity in anticipation of daily meal time. Interestingly, rats also show increased activity in anticipation of a daily palatable meal even when they have an ample food supply, suggesting a role for brain reward systems in anticipatory behavior, and providing an alternate model by which to study the neurobiology of anticipation in species, such as mice, that are less well adapted to “stuff and starve” feeding schedules. To extend this model to mice, and exploit molecular genetic resources available for that species, we tested the ability of wild-type mice to anticipate a daily palatable meal. We observed that mice with free access to regular chow and limited access to highly palatable snacks of chocolate or “Fruit Crunchies” avidly consumed the snack but did not show anticipatory locomotor activity as measured by running wheels or video-based behavioral analysis. However, male mice receiving a snack of high fat chow did show increased food bin entry prior to access time and a modest increase in activity in the two hours preceding the scheduled meal. Interestingly, female mice did not show anticipation of a daily high fat meal but did show increased activity at scheduled mealtime when that meal was withdrawn. These results indicate that anticipation of a scheduled food reward in mice is behavior, diet, and gender specific.
Liturgy as space for anticipation  [cached]
Johan Cilliers
HTS Theological Studies/Teologiese Studies , 2011, DOI: 10.4102/hts.v67i2.1020
Abstract: This article proposes that the notion of liturgical space, understood in conjunction with the original Greek concept of space, is not only a quantitative, physical locality, but also a primary qualitative possibility for existence, a meaningful womb, a neighbourhood for imagination and a space for anticipation. Three consequences of this proposal are discussed, namely liturgy as waiting on the elusive presence (presence of absence) of God, celebration as (metaphorical) dance of hope, and the need for liturgical refiguring. How to cite this article: Cilliers, J., 2011, ‘Liturgy as space for anticipation’, HTS Teologiese Studies/Theological Studies 67(2), Art. #1020, 7 pages. http://dx.doi.org/10.4102/hts.v67i2.1020
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