bluuebunny/crossref_metadata_2025_split huggingface dataset:
Nosocomial Acinetobacter pneumonia: Treatment and prognostic factors in 356 cases
Authors: Özvatan Tülay , Akalın Halis , Sınırtaş Melda , Ocakoğlu Gökhan , Yılmaz Emel , Heper Yasemin , Kelebek Nermin , İşçimen Remzi , Kahveci Ferda 
Published: December 2015

AbstractBackground and objectiveAcinetobacter baumannii and A. baumannii/calcoaceticus complex are commonly encountered pathogens in nosocomial infections. This study aimed to evaluate the treatment and prognostic risk factors in nosocomial pneumonia caused by these microorganisms.MethodsThe study was conducted retrospectively in Uludag University Hospital and included 356 adult non‐neutropenic patients with nosocomial pneumonia.ResultsOf the subjects, 94.9% (n = 338) had ventilator‐associated pneumonia. The clinical response rate was 57.2%, the 14‐day mortality 39.6% and the 30‐day mortality 53.1%. The significant independent risk factors for the 30‐day mortality were severe sepsis (OR, 2.60; 95% CI: 1.49–4.56; P = 0.001), septic shock (OR, 6.12; 95% CI: 2.75–13.64; P < 0.001), APACHE II score ≥ 20 (OR, 2.12; 95% CI: 1.28–3.50; P = 0.003) and empiric monotherapy (OR, 1.63; 95% CI: 1.00–2.64; P = 0.048). Multi‐trauma (OR, 2.50; 95% CI: 1.11–5.68; P = 0.028) was found to be a protective factor. In patients with a clinical pulmonary infection score (CPIS) > 6 on the third day of treatment, both the 14‐ and 30‐day mortality rates were high (P < 0.001, P < 0.001). Also, the 14‐ and 30‐day mortality rates were significantly higher in the patients treated with empiric monotherapy compared with combination therapy (48/93 (51.6%)–46/123 (37.4%), P = 0.037 and 62/93 (66.7%)–65/123 (52.8%), P = 0.041, respectively) in pneumonia caused by imipenem‐resistant strains.ConclusionMortality rates were high in pneumonia caused by imipenem‐resistant A. baumannii or A. baumannii/calcoaceticus complex. In the units with a high level of carbapenem resistance, antibiotic combinations should be considered for empiric therapy.
Crime scenes and mystery players! Using driving questions to support the development of statistical literacy
Authors: Leavy Aisling , Hourigan Mairead 
Published: December 2015

AbstractWe argue that the development of statistical literacy is greatly supported by engaging students in carrying out statistical investigations. We describe the use of driving questions and interesting contexts to motivate two statistical investigations. The PPDAC cycle is use as an organizing framework to support the process statistical investigation.
Successful treatment of severe hypokalemia in a dog with acute kidney injury caused by leptospirosis
Authors: Allen Ashley E. , Buckley Gareth J. , Schaer Michael 
Published: December 2015

AbstractObjectiveTo report the case management of a patient with severe hypokalemia resulting in cardiopulmonary arrest caused by infection with leptospirosis.Case SummaryA 3‐year‐old intact female Dachshund presented for polyuria, polydipsia, and refractory hypokalemia, which progressed to flaccid paralysis and cardiorespiratory arrest. Following successful resuscitation, the dog was apneic and managed with mechanical ventilation while volume status and electrolytes were corrected. The dog showed rapid improvement allowing for weaning from the ventilator within the first day. The dog was identified as having leptospirosis causing severe kaliuresis (fractional excretion of potassium 31%). Following discharge from hospital, the dog was managed with doxycycline, oral potassium supplementation, and spironolactone and made a full clinical recovery.New or Unique Information ProvidedThis report identifies an unusually severe presentation of leptospirosis in a dog from a region where the disease is not considered common, which was successfully treated despite cardiopulmonary arrest on initial presentation.
Stem cell‐derived astrocytes: are they physiologically credible?
Authors: Hill Eric , Nagel David , Parri Rheinallt , Coleman Michael 
Published: December 2015

AbstractAstrocytes are now increasingly acknowledged as having fundamental and sophisticated roles in brain function and dysfunction. Unravelling the complex mechanisms that underlie human brain astrocyte–neuron interactions is therefore an essential step on the way to understanding how the brain operates. Insights into astrocyte function to date have almost exclusively been derived from studies conducted using murine or rodent models. Whilst these have led to significant discoveries, preliminary work with human astrocytes has revealed a hitherto unknown range of astrocyte types with potentially greater functional complexity and increased neuronal interaction with respect to animal astrocytes. It is becoming apparent, therefore, that many important functions of astrocytes will only be discovered by direct physiological interrogation of human astrocytes. Recent advancements in the field of stem cell biology have provided a source of human‐based models. These will provide a platform to facilitate our understanding of normal astrocyte functions as well as their role in CNS pathology. A number of recent studies have demonstrated that stem cell‐derived astrocytes exhibit a range of properties, suggesting that they may be functionally equivalent to their in vivo counterparts. Further validation against in vivo models will ultimately confirm the future utility of these stem cell‐based approaches in fulfilling the need for human‐based cellular models for basic and clinical research. In this review we discuss the roles of astrocytes in the brain and highlight the extent to which human stem cell‐derived astrocytes have demonstrated functional activities that are equivalent to those observed in vivo.
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Changes in sarcomere length during isometric tension development in frog skeletal muscle
Authors: Cleworth D. R. , Edman K. A. P. 
Published: December 2015

1. Changes in sarcomere length during isometric contraction of isolated semitendinosus muscle fibres from the frog were studied using laser diffraction techniques. Movements of the first‐order diffraction line relative to the zero‐order reference were recorded from a screen on continuously moving film. Sarcomere length changes of 50 Å could be resolved in this way.2. Following a latent period of approximately 12 msec after the stimulus of a single skeletal muscle fibre at 1–2° C, there appeared to be a simultaneous onset of tension development and sarcomere shortening. Provided that the fibre was uniformly excited along its length, different regions shortened together by approximately the same amount. The extent of the shortening was a function of the total compliance of the tendons and tension measuring device.3. During the plateau of a smooth tetanus no fluctuations of first‐order line width or zero‐ to first‐order line spacing were detectable at any point examined along the preparation. This finding provides evidence that, in a functionally intact fibre, no synchronous oscillations of the sarcomeres, at least no length changes exceeding 50 Å, occur during a fused tetanus. Furthermore, the fact that the first‐order line did not increase in width as the preparation went from rest to full activity indicates that contraction proceeds without appreciable change in distribution of sarcomere lengths.4. The sarcomere movements during relaxation differed along the length of the fibre. As the tension declined smoothly, sarcomeres in some parts of the fibre underwent further shortening, while the end sarcomeres near the tendons and in one or two regions in the middle segment of the fibre were further extended. These data indicate that the duration of the mechanical activity differs in different regions along the length of the fibre. The pattern of relaxation, i.e. the behaviour of the sarcomeres in different fibre segments, is unique to any particular fibre.
The geometrical factors determining the electrotonic properties of a molluscan neurone
Authors: Mirolli Maurizio , Talbott Susan R. , Mirolli Maurizio 
Published: December 2015

1. Light and electron micrographs of sections of the gastro‐oesophageal giant neurone (G cell) of the nudibranch mollusc, Anisodoris nobilis, show that its somatic and axonal membranes are deeply infolded. The surface and volume of its soma and axon have been calculated from measurements taken at the light and electron microscope on sections of the G cell.2. The surface of the soma is approximately 7·5 times as large as that of a sphere having the same volume. For a typical cell the soma has a volume of 1·5 × 10−5 cm3 and a surface of 2 × 10−2 cm2; the axon has a volume of 5 × 10−5 cm3 and a surface of 5 × 10−1 cm2.3. Because the axon is star shaped in cross‐section, its geometry cannot be described by a single parameter (diameter or radius). Furthermore, the axon is beaded, and both the area (A) and the perimeter (P) of its cross‐section change from point to point.4. However, in spite of the apparent irregularity of their cross‐sections, all axons examined could be characterized by a constant A/P ratio. This ratio also remains constant when the axons are stretched.5. According to the equations derived in the Appendix, the geometrical factor for the length constant in a folded fibre is H = √(A/P); therefore, in the G cell the length constant (and hence the conduction velocity) should be independent of the stretch applied to the axon.6. The geometrical factor required to calculate the axonal input conductance is M = √(A.P). M changes in adjacent segments of the same axon; in each segment its value depends on how much the axon is stretched.7. The input conductance of the whole axon can be calculated by applying a modified form of Rall's equations for dendritic trees. The results suggest that the input conductance of the G cell axon should vary with stretch and should be large in comparison to that of the soma.
The binding of labelled tetrodotoxin to non‐myelinated nerve fibres
Authors: Colquhoun D. , Henderson R. , Ritchie J. M. 
Published: December 2015

1. Tritiated tetrodotoxin has been prepared and purified, and its binding to rabbit, lobster, and garfish non‐myelinated nerve fibres examined.2. In each case a component of the binding curve was found that saturated at concentrations of a few nanomolar.3. In addition, non‐specific binding, indicated by a linear dependence of the amount bound on concentration, occurred.4. The kinetics of wash‐in and wash‐out of the radioactive toxin were consistent with a model in which all binding was rapid and reversible and in which diffusion into and out of the nerve bundle was rate‐limiting. This was shown by numerical solution of the appropriate non‐linear diffusion equation. An extension of the limited biophase model that allows for non‐specific binding was shown to give good semiquantitative approximations to the proper diffusion equation; and (unlike the latter) the extension was shown to have a relatively simple solution.5. A number of pharmacological agents were tested for competition with, or perturbation of, tetrodotoxin binding: sodium, calcium and hydrogen ions, lidocaine, batrachotoxin and saxitoxin. Apart from a small calcium effect, only saxitoxin, whose effect on sodium current is similar to that of tetrodotoxin, was found to interfere with binding. Increasing saxitoxin concentrations resulted in reduced amounts of tetrodotoxin binding in a manner consistent with a competition between the two toxins for the same site.
Composition of fluid obtained from choroid plexus tissue isolated in a chamber in situ*
Authors: Miner L. C. , Reed D. J. 
Published: December 2015

1. A method was developed for isolating a segment of the choroid plexus of the lateral ventricle of the cat brain in a chamber in situ.2. A comparison of electrolyte and protein concentrations in serum, ultrafiltrate of serum, cisterna magna fluid, fluid accumulated in the chamber and fluid collected from the choroid plexus by another technique, demonstrates that the chamber fluid is a secretory product of the choroid plexus.3. The rate of fluid formation in the chamber was 0·4 μl. min−1 mg−1 of tissue, a value in good agreement with reports in the literature.4. The observation that the concentration of K+ in choroid plexus fluid was lower than that in the serum ultrafiltrate suggests that K+ is regulated by an active transport process at the choroid plexus.5. Significant correlation was found between electrolyte values and the protein content of the chamber fluid. This suggests that plasma is the probable source of the protein in the chamber fluid and that K+ and probably Ca2+ and Mg2+ in c.s.f. are subject to active homoeostatic regulation by the choroid plexus.6. The technique described provides a new opportunity to study in detail the functional characteristics of the choroid plexus.
Ionic basis of membrane potentials of epithelial cells in rat small intestine
Authors: Barry R. J. C. , Eggenton Jacqueline 
Published: December 2015

1. Potentials across the mucosal and serosal membranes of the epithelial cells of rat jejunum together with transmural potentials were recorded using everted sac preparations.2. Ionic changes in either mucosal or serosal fluids affect mucosal or serosal membrane potentials respectively with comparable changes in the transmural potential. The contralateral membrane potential is relatively unaffected.3. Replacement of mucosal sodium chloride by potassium chloride or lithium chloride had little effect on potentials, but its replacement by mannitol or Tris chloride increased the negativity of the mucosal potential, giving linear relationships against log10[Na]m with slopes of 41·4 and 30·7 mV respectively for tenfold change in [Na]m.4. At constant [Na]m, potassium or lithium increased the mucosal potential by 25·7 and 19·8 mV respectively for tenfold concentration changes.5. Qualitatively similar changes occurred in the serosal potential when the ionic composition of the serosal fluid was varied.6. Mucosal potential changes in response to modifications of the ionic composition of the mucosal fluid were the same in the presence and absence of galactose.7. Sodium and potassium diffusion potentials largely determine both the mucosal and serosal membrane potentials. For the mucosal membrane, PK:PNa is 1·26:1, and is probably higher for the serosal membrane. Chloride makes no significant contribution to membrane potentials.8. Potentials generated by the electrogenic sodium pump are superimposed on diffusion potentials across the serosal membrane.
The effects of stimulation of the left atrial receptors on sympathetic efferent nerve activity
Authors: Karim F. , Kidd C. , Malpus C. M. , Penna P. E. 
Published: December 2015

1. Activation of left atrial receptors by distension of balloons at the pulmonary vein—atrial junctions caused an increase in the cardiac sympathetic nerve activity, a decrease in the renal sympathetic nerve activity, and no change in the lumbar and splenic sympathetic nerve activity.2. The cardiac and renal nerve responses to balloon distension were abolished by vagal blockade in the neck.3. The results provide additional evidence that the reflex increase in the heart rate following stimulation of the left atrial receptors is mediated by selective activation of cardiac sympathetic nerve fibres.4. The inhibitory effect of atrial receptor activation on the renal sympathetic nerve activity suggests that a neural factor, possibly involving renal haemodynamics, may be a component of the diuretic response to the activation of the left atrial receptors.5. The results provide further evidence for the selective nature of the pattern of reflex responses to left atrial receptor activation and show for the first time a directionally fractionated response from sympathetic efferent neurones.
S‐potentials in the dark‐adapted retina of the carp
Authors: Kaneko Akimichi , Yamada Masahiro 
Published: December 2015

1. S‐potentials were recorded in the dark‐adapted carp retina. After recording, Procion Yellow was injected from the recording electrode to identify histologically the cell recorded.2. Both L‐ and C‐type S‐potentials were found. L‐type S‐potentials were further classified into two groups. The first group was characterized by a high threshold, fast rise and fall times and a spectral sensitivity peak of about 620 nm. The second group showed a low threshold, slow response time course and a spectral sensitivity peak of about 520 nm.3. Cells of the first group were identified as external and internal horizontal cells. Cells of the second group were identified as intermediate horizontal cells.4. In the dark‐adapted retina, the spectral sensitivity of the intermediate horizontal cell showed a good agreement with the absorption spectrum of the rod pigment, porphyropsin.5. Neither a chromatic background nor white background illumination of moderate intensity (1 cd.m−2) shifted the spectral sensitivity of the intermediate horizontal cell.6. Under a strong background (10 cd.m−2), the intermediate horizontal cell was entirely suppressed. Under the same conditions the external horizontal cell was still capable of responding.7. From these observations it is concluded that the intermediate horizontal cell receives input from rods only.
The voltage dependence of the chloride conductance of frog muscle
Authors: Hutter O. F. , Warner Anne E. 
Published: December 2015

1. The effect of extracellular pH changes on the voltage—current relation of frog muscle membrane has been studied using intracellular microelectrodes. To reduce the cation conductance of the membrane, potassium in Ringer solution was replaced by rubidium.2. When the relatively impermeant methyl sulphate ion replaced extracellular chloride the membrane conductance was low, time independent and little influenced by extracellular pH changes. The voltage—current relation was linear at both high and low pH values.3. In rubidium Ringer solution at pH 7·4 the membrane conductance fell as the inside of the fibre was made more negative, in a manner consistent with the predictions of the constant field theory.4. At a high pH value (9·8) the resting conductance was high, but it fell steeply as the membrane potential was increased; for large hyperpolarizing voltages the membrane current tended to a limiting value. The voltage—current relation crossed those recorded at pH 7·4 and 5·0.5. In acid Ringer solution (pH 5·0) the resting membrane conductance was low and remained constant until the membrane potential was hyperpolarized more than 30 mV beyond the resting value; the conductance then rose as the membrane potential was further increased. For large hyperpolarizations the membrane conductance was higher at pH 5·0 than at pH 9·8.6. Experiments using two successive, identical, constant current pulses suggested that the membrane conductance altered during the passage of current across the membrane; in alkaline solution the conductance fell with time, in acid solution it rose.7. Because no time or voltage dependence of the membrane conductance was seen in the absence of chloride ions it is inferred that the movements of chloride ions across the muscle membrane are responsible for both the time and voltage dependent alterations in membrane conductance seen at different pH values.
Kinetic properties of the chloride conductance of frog muscle
Authors: Warner Anne E. 
Published: December 2015

1. The anion conductance of frog muscle has been studied at alkaline, neutral and acid extracellular pH values using a voltage clamp technique. Potassium in the extracellular solution was replaced by rubidium in order to simplify the behavior of the cation conductance.2. At pH 9·8 the chloride conductance fell exponentially during a hyperpolarizing voltage step. The speed of inactivation was directly proportional to the hyperpolarization from the holding potential; at 60 mV the rate constant was about 0·01 msec−1.3. An exponential fall in chloride current during the voltage pulse also occurred at pH 7·4; the speed of inactivation, which was proportional to the membrane potential, was about 20% greater at neutral than at alkaline pH values.4. The instantaneous voltage—current relation was approximately linear at pH 7·4 and 9·8; the instantaneous conductance was always greater at the alkaline pH value.5. At neutral pH values when there were no time‐dependent conductance changes the voltage—current relation was linear.6. In acid solutions (pH 5·0) the chloride current gradually increased during a hyperpolarizing voltage step. The time course of this increase was complex, but it took place at greater speed during large voltage steps.7. Comparison of the steady‐state voltage—current relations measured in the absence and presence of chloride ions confirmed that in alkaline solutions the chloride current could reach a limiting value.8. The equilibrium potential for the time‐dependent conductance changes was close to the holding potential.
Lectoescritura y pensamiento crítico: desafío de la educación contable
Authors: Rojas Rojas William 
Published: December 2015

<p align="LEFT">Este texto defiende la formación para el pensamiento crítico que se ancla en un campo de disertación que vincula la dignidad humana con el desarrollo de la disciplina contable. A partir de un trabajo documental y una problematización contextual, se examina cómo el pensar-vivir hipermoderno desechó el poder de la razón crítica como un medio fundamental para promover proyectos ético-políticos orientados hacia el reconocimiento de miles de seres humanos que en la actualidad son excluidos y desechados por y desde los postulados del modelo neoliberal globalizado. Se describe cómo las contradicciones socioeconómicas del modelo de desarrollo imperante exigen que los programas de Contaduría Pública repiensen sus Proyectos Educativos (PE) para descifrar cómo pueden salir al encuentro de sus estudiantes y acompañarlos en su proceso de formación. Se concluye que la simple lectoescritura funcional, ajena al pensamiento crítico, lleva a la emergencia <span style="font-family: Whitman-Roman; font-size: xx-small;"><span>del </span></span><em><span style="font-family: Whitman-Italic; font-size: xx-small;" lang="JA"><span lang="JA">computat</span></span><span style="font-family: TimesNewRomanPS-ItalicMT; font-size: xx-small;"><span>ō</span></span><span style="font-family: Whitman-Italic; font-size: xx-small;" lang="JA"><span lang="JA">ris globalizzatus </span></span></em><span style="font-family: Whitman-Roman; font-size: xx-small;"><span>que no pueden fácilmente </span></span>articular su saber y sus experticias profesionales a las necesidades de su sociedad. Se finaliza proponiendo unas recomendaciones que faciliten proyectar las reformas a los PE y a los desarrollos de las maestrías en contabilidad. </p>
La privatización del asesoramiento agrícola: Consecuencias para los productores lecheros del valle del Mantaro, Perú
Authors: Faure Guy , Huamanyauri Méndez Kary , Salazar Ivonne , Gómez Carlos , De Nys Erwin , Dulcire Michel 
Published: December 2015

<p>A nivel mundial, el papel del sector privado en el asesoramiento agrícola ha venido incrementándose desde los años ochenta y noventa. Una muestra de tal evolución se observa en el valle del Mantaro (Perú), en un contexto de pequeña agricultura. Para evaluar sus consecuencias, se realizaron entrevistas con proveedores de<br />insumos, extensionistas y productores. En este caso, el asesoramiento privado se realiza de manera asociada a la venta de insumos, lo cual, si bien favorece el acceso de un apoyo técnico a casi todos los productores, no considera sus necesidades globales. Esta investigación muestra la importancia de una mejor coordinación entre los actores públicos y privados del sistema de asesoramiento agrícola.</p>