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The extensive philosophical discussions and analyses in recent decades of function-talk in biology have done much to clarify what biologists mean when they ascribe functions to traits, but the basic metaphysical question—is there genuine teleology and design in the natural world, or only the appearance of this?—has persisted, as recent work both defending, and attacking, teleology from a Darwinian perspective, attest. I argue that in the context of standard contemporary evolutionary theory, this is for the most part a verbal, rather than a substantive dispute: the disputants are talking past one another. To justify this claim I develop a general framework within which reductionist views, such as the standard ‘etiological’ account of biofunctions, occupy an intermediate position between what I call full-blooded realism and full-blooded anti-realism, and suggest that whether such views count as ‘realist’ views has no objective, theory-neutral answer.

Evolutionary debunking arguments (EDAs) seek to infer from the evolutionary origin of human beliefs about a particular domain to the conclusion that those beliefs are unjustified. In this paper I discuss EDAs with respect to our everyday, commonsense beliefs. Those who seriously entertain EDAs for commonsense argue that natural selection does not care about truth, it only cares about fitness, and thus it will equip us with beliefs that are useful (fitness-enhancing) rather than true. In recent work Griffiths and Wilkins argue that this is a mistake. Fitness-tracking and truth-tracking are not rival, but rather potentially complementary, hypotheses about the function of our cognitive belief-forming systems. It may be that those systems maximise fitness by tracking the truth. I argue that while they are right about the standard EDAs for commonsense, the threat of evolutionary scepticism remains, because cognitive systems whose function is to track the truth may still be highly unreliable. I propose an alternative, Moorean approach to vindicating our commonsense picture of the world and dispelling the threat of scepticism. Once this has been established, however, we may appeal to evolution to explain the good fit between our cognition and the world. I thus propose that an evolutionary explanatory project ought to replace the troubled evolutionary justificatory project. This ought to be appealing to those such as Griffiths and Wilkins who seek a naturalistic non-sceptical account of our commonsense beliefs and their origins.

Creationists have long argued that evolutionary science is committed to a dogmatic metaphysics of naturalism and materialism, which is based on faith or ideology rather than evidence. The standard response to this has been to insist that science is not committed to any such metaphysical doctrine, but only to a methodological version of naturalism, according to which science may only appeal to natural entities and processes. But this whole debate presupposes that there is a clear distinction between the natural and the supernatural, and thus that naturalism is a meaningful doctrine. I argue that this assumption is false. The concepts of the natural and the supernatural are in fact hopelessly obscure, such that the claim that science is committed to methodological naturalism cannot be made good. This is no victory for anti-naturalists however; explicitly supernaturalist theories, such as Creationism, can be ruled out of scientific consideration as a priori incoherent, given that they presuppose for their intelligibility that there is a meaningful natural-supernatural distinction. This is not the case for standard scientific theories however, as they are not explicitly naturalistic theories; they do not postulate natural or physical entities or processes as such.

It is widely acknowledged that metaphysical assumptions, commitments and presuppositions play an important role in science. Yet according to the empiricist there is no place for metaphysics as traditionally understood in the scientific enterprise. In this paper I aim to take a first step towards reconciling these seemingly irreconcilable claims. In the first part of the paper I outline a conception of metaphysics and its relation to science that should be congenial to empiricists, motivated by van Fraassen’s work on ‘stances’. There has been a considerable about of recent work devoted to van Fraassen’s ‘stance’ view, but it has not on the whole been noticed that the view has the potential to motivate a general empiricist conception of the relation between science and metaphysics. In the second and third sections I discuss two examples from biology to illustrate this conception: metaphysical punctuationism, and its relation to and influence on the thesis of punctuated equilibrium; and dialectical biology as defended by Levins and Lewontin.

Incomplete instrumentation and a lack of biofidelity in the extremities of the 6 year-old anthropomorphic test device (ATD) pose challenges when studying regions of the body known to interact with the vehicle interior. This study sought to compare a prototype Hybrid III 6 year-old ATD leg (ATD-LE), with a more biofidelic ankle and tibia load cell, to previously collected child volunteer data and to the current Hybrid III 6 year-old ATD (HIII). Anthropometry, range of motion (ROM), and stiffness measurements were taken, along with a dynamic evaluation of the ATD-LE using knee-bolster airbag (KBA) test scenarios. Anthropometry values were similar in eight of twelve measurements. Total ankle ROM was improved in the ATD-LE with no bumper compared to the HIII. The highest tibia moments and tibia index values were recorded in KBA scenarios when the toes were positioned in contact with the dashboard prior to airbag deployment, forcing the ankle into axial loading and dorsiflexion. While improvements in the biofidelity of the ATD-LE are still necessary, the results of this study are encouraging. Continued advancement of the 6 year-old ATD ankle is necessary to provide a tool to directly study the behavior of the leg during a motor vehicle crash.

Chronic obstructive pulmonary disease (COPD) is one of the prevalent causes of worldwide mortality and encompasses two major clinical phenotypes, i.e., chronic bronchitis (CB) and emphysema. The most common cause of COPD is chronic tobacco inhalation. Research focused on the chronic bronchitic phenotype of COPD has identified several pathological processes that drive disease initiation and progression. For example, the lung’s mucociliary clearance (MCC) system performs the critical task of clearing inhaled pathogens and toxic materials from the lung. MCC efficiency is dependent on: (i) the ability of apical plasma membrane ion channels such as the cystic fibrosis transmembrane conductance regulator (CFTR) and the epithelial Na+ channel (ENaC) to maintain airway hydration; (ii) ciliary beating; and, (iii) appropriate rates of mucin secretion. Each of these components is impaired in CB and likely contributes to the mucus stasis/accumulation seen in CB patients. This review highlights the cellular components responsible for maintaining MCC and how this process is disrupted following tobacco exposure and with CB. We shall also discuss existing therapeutic strategies for the treatment of chronic bronchitis and how components of the MCC can be used as biomarkers for the evaluation of tobacco or tobacco-like-product exposure.

I consider the broad perspectives in biology known as ‘functionalism’ and ‘structuralism’, as well as a modern version of functionalism, ‘adaptationism’. I do not take a position on which of these perspectives is preferable; my concern is with the prior question, how should they be understood? Adapting van Fraassen’s argument for treating materialism as a stance, rather than a factual belief with propositional content, in the first part of the paper I offer an argument for construing functionalism and structuralism as stances also. The argument draws especially on Gould’s (The structure of evolutionary theory. Harvard University Press, Cambridge, 2002) insights concerning functionalism and structuralism, in particular their apparent historical continuity from the pre-Darwinian period through to today. In the second part of the paper I consider Godfrey-Smith’s distinction between empirical and explanatory adaptationism, and suggest that while the former is an empirical scientific hypothesis, the latter is closely related to the functionalist stance.

Cushion plants have long fascinated botanists for their ability to cope with extreme environments in most mountains and arctic regions of the world. One century ago, a first worldwide catalogue of species forming cushions was published by Hauri and Schroter (Bot Jahrb Syst Pflanzengesch Pflanzengeogr 50:618–656, 1914). Here, we defined a simplified typology of cushion plants and updated the worldwide catalogue of cushion species, along with information on their geographic distribution. This compilation was based on available information in floras and catalogues but also in efloras and virtual encyclopedias, which were screened using automated database queries. We established a list of 1,309 cushion-forming species distributed in 272 genera and 63 families of angiosperms. Compact cushions are represented by 678 species, among which 587 species exhibit a hemispherical shape, and 91 species exhibit a flat to mat shape. We found 398 species forming non-compact hemispherical cushions. The list of cushion species has significantly increased since Hauri and Shroter, due to the description of new species, updated regional inventories, and improved access to electronic databases. Uncertainties in the delineation of the cushion life form are discussed, notably for non-compact growth forms. A website has been launched to display the catalogue and enable a collaborative improvement of the database (http://www.cushionplants.eu/). The distribution of the species is presented on the basis of the world geographical scheme for recording plant distributions and global biodiversity information facility data. This catalogue will serve as a reference database for further analyses on the biogeography and evolutionary history of cushion plants and arctico-alpine biotas.

Since van Fraassen first put forward the suggestive idea that many philosophical positions should be construed as ‘stances’ rather than factual beliefs, there have been various attempts to spell out precisely what a philosophical stance might be, and on what basis one should be adopted. In this paper I defend a particular account of stances, the view that they are pragmatically justified perspectives or ways of seeing the world, and compare it to some other accounts that have been offered. In Sect. 2 I consider van Fraassen’s argument for construing empiricism as a stance, and look at some responses to it. In Sect. 3 I outline my conception of stances as perspectives or ways of seeing, and explain how stances so understood may be justified. I illustrate this conception by way of a discussion of the model pluralist position with respect to the units of selection debate in biology, and suggest that on the model pluralist view different perspectives on the units of selection, such as the gene’s eye view, are in fact van Fraassian stances. In Sect. 4 I discuss the view put forward by Teller and Chakravartty among others that stances should be understood as epistemic policies, and argue that it is consistent with the conception of stances as perspectives. In the final section I criticise Rowbottom’s attempt to assimilate stances to Kuhnian paradigms. I argue that he has overlooked some important disanalogies between stances and paradigms, so that the comparison obscures more than it reveals.

Micro-electro-mechanical-system (MEMS) switches are very interesting for high frequency applications. These switches are electrostatically actuated micromechanical meanders-suspended bridges. In the field of millimeter wave radio astronomy, cryogenic circuits are frequently made of superconducting niobium and elements combining these circuits with MEMS devices of compatible technologies are of high potential for new applications. The initial profile of the bridge has been numerically simulated. This suggested the influence of possible residual stress in Nb thin films on the behavior of MEMS. A study of the capacitance variation as a function of the applied voltage has been performed for this type of MEMS at room and low temperatures down to 150 K. It is associated with a mechanical study of the vibrating modes of the structure and with X-rays characterization of the Nb film. An identification of specific sets of geometric parameters to reach good performance and temperature stability was done.

Respiratory surfaces are exposed to billions of particulates and pathogens daily. A protective mucus barrier traps and eliminates them through mucociliary clearance (MCC). However, excessive mucus contributes to transient respiratory infections and to the pathogenesis of numerous respiratory diseases. MUC5AC and MUC5B are evolutionarily conserved genes that encode structurally related mucin glycoproteins, the principal macromolecules in airway mucus. Genetic variants are linked to diverse lung diseases, but specific roles for MUC5AC and MUC5B in MCC, and the lasting effects of their inhibition, are unknown. Here we show that mouse Muc5b (but not Muc5ac) is required for MCC, for controlling infections in the airways and middle ear, and for maintaining immune homeostasis in mouse lungs, whereas Muc5ac is dispensable. Muc5b deficiency caused materials to accumulate in upper and lower airways. This defect led to chronic infection by multiple bacterial species, including Staphylococcus aureus, and to inflammation that failed to resolve normally. Apoptotic macrophages accumulated, phagocytosis was impaired, and interleukin-23 (IL-23) production was reduced in Muc5b(-/-) mice. By contrast, in mice that transgenically overexpress Muc5b, macrophage functions improved. Existing dogma defines mucous phenotypes in asthma and chronic obstructive pulmonary disease (COPD) as driven by increased MUC5AC, with MUC5B levels either unaffected or increased in expectorated sputum. However, in many patients, MUC5B production at airway surfaces decreases by as much as 90%. By distinguishing a specific role for Muc5b in MCC, and by determining its impact on bacterial infections and inflammation in mice, our results provide a refined framework for designing targeted therapies to control mucin secretion and restore MCC.

We examine the contribution of the Doppler Orbit determination and Radiopositioning Integrated by Satellite (DORIS) technique to the International Terrestrial Reference Frame (ITRF2005) by evaluating the quality of the submitted solutions as well as that of the frame parameters, especially the origin and the scale. Unlike the previous versions of the ITRF, ITRF2005 is constructed with input data in the form of time-series of station positions (weekly for satellite techniques and daily for VLBI) and daily Earth orientation parameters (EOPs), including full variance–covariance information. Analysis of the DORIS station positions’ time-series indicates an internal precision reaching 15 mm or better, at a weekly sampling. A cumulative solution using 12 years of weekly time-series was obtained and compared to a similar International GNSS Service (IGS) GPS solution (at 37 co-located sites) yielding a weighted root mean scatter (WRMS) of the order of 8 mm in position (at the epoch of minimum variance) and about 2.5 mm/year in velocity. The quality of this cumulative solution resulting from the combination of two individual DORIS solutions is better than any individual solution. A quality assessment of polar motion embedded in the contributed DORIS solutions is performed by comparison with the results of other space-geodetic techniques and in particular GPS. The inferred WRMS of polar motion varies significantly from one DORIS solution to another and is between 0.5 and 2 mas, depending on the strategy used and in particular estimating or not polar motion rate by the analysis centers. This particular aspect certainly needs more investigation by the DORIS Analysis Centers.

For testing Group 4 unfired pressure vessels designed according to the European Standard EN 13445, not subject to non-destructive testing other than visual inspection, the hydraulic proof test is expected not only to prove leak tightness but also to improve the vessel’s reliability (500 full pressure cycles minimum fatigue life). In the HYDFAT research program two complementary approaches were combined to investigate the benefits of the hydraulic test pressure on the fatigue life. (1): Numerical modeling allowing for the determination of the critical weld defect size under various pressure test conditions, complemented by tests on wide plates and small-scale vessels (wall thickness 6 and 12 mm) containing weld defects. (2): Statistical investigation (multivariate analysis) of a series of experiments on thin-walled vessels (≤ 6 mm). It was concluded that the hydrotest pressure had to be as high as possible and ratios of test pressure to the maximum allowable pressure were proposed for ferritic and austenitic steels. However the maximum allowable peaking for testing Group 4 vessels should be lower than that currently allowed in EN 13445 for vessels of other testing Groups. These results have been implemented in the first edition of the European standard EN 13445 published in May 2002.

Electrical probes are an excellent tool for local measurements of basic plasma parameters, fluctuations and plasma flow studies. However, the application of a probe diagnostics is usually accompanied by theoretical restrictions, practical limitations and problems. In this paper we describe the new probe system recently developed for the TOMAS toroidal device (Forschungszentrum Julich, Germany). This system comprises multi-collector Gundestrup probe for flow measurements and Langmuir probe for plasma characterization. During development of such a system, several physical and technical issues, which are common for probe applications, were solved or essentially suppressed.

To determine the efficacy of potential cystic fibrosis (CF) therapies we have developed a novel mucociliary transit (MCT) measurement that uses synchrotron phase contrast X-ray imaging (PCXI) to non-invasively measure the transit rate of individual micron-sized particles deposited into the airways of live mice. The aim of this study was to image changes in MCT produced by a rehydrating treatment based on hypertonic saline (HS), a current CF clinical treatment. Live mice received HS containing a long acting epithelial sodium channel blocker (P308); isotonic saline; or no treatment, using a nebuliser integrated within a small-animal ventilator circuit. Marker particle motion was tracked for 20 minutes using PCXI. There were statistically significant increases in MCT in the isotonic and HS-P308 groups. The ability to quantify in vivo changes in MCT may have utility in pre-clinical research studies designed to bring new genetic and pharmaceutical treatments for respiratory diseases into clinical trials.

Station coordinates are combined with velocities estimated by space geodesy techniques to produce the International Terrestrial Reference System. The input is sets of coordinates and velocities calculated by International Earth Rotation Service analysis centers using space geodesy techniques. The working reference system of individual analysis centers is generally conventionally defined. However, the implications of such processing can have an effect on the resulting combined set. The problem of datum definition as a function of coordinate combinations is reviewed. In particular, the problem of minimum constraints is clearly emphasized and the reference system effect is defined. The goal is to build a process that could be used generally to remove uncertainties in the underlying coordinate system without disturbing the underlying information with additional unnecessary information.

The 2D multifluid code TECXY has been used to model the experimental biasing of the toroidal belt limiter ALT-II on the tokamak TEXTOR-94 with respect to the first wall. It is well known that the edge flow pattern can be influenced by the poloidal electric drifts from imposing radial electric fields. The modelling with TECXY introduces imprinted bias currents in the scrape-off layer for the case of negative (limiter) biasing, and imprinted bias potentials for the case of positive biasing. This allows to simulate sufficiently well the experimental current-voltage characteristics for either biasing and also reproduces the essential features and trends of the observed plasma profiles in the SOL. A moderate negative biasing is found to be optimal for the exhaust efficiency of the pump limiter.

Particle collection by the ALT-II belt limiter in the TEXTOR-94 tokamak is exclusively limited to the parallel outflux because the scoop walls that are oriented parallel to the field lines obstruct the poloidal E×B mass flow. With normal B tor direction (E×B towards the scoops), a threefold decrease of plenum pressure is measured during negative biasing, while with reversed B tor (E×B away from the scoops), a 60% pressure increase is observed. This behaviour is exactly opposite to that observed in X-point divertors. A simple fluid model explains this apparent contradiction, and gives good quantitative agreement with measurements of the parallel Mach number in the SOL. The essential physics is governed by the Bohm-Chodura criterion.

Cystic fibrosis (CF) is a syndrome caused by mutations in the cystic fibrosis transmembrane regulator (CFTR) gene. Despite advances in our understanding of the molecular pathogenesis of CF, the link between CFTR gene mutations and the pathogenesis of CF lung disease remains poorly defined. CFTR has been assigned a number of putative functions that may contribute to innate airway defense, including the regulation of adenosine 5′-triphosphate (ATP) release into the extracellular environment. Because extracellular ATP and uridine 5′-triphosphate (UTP) may regulate airway mucociliary clearance via interaction with luminal P2Y2 receptors, the loss of CFTR-mediated nucleotide release could explain the defect in CF airway defense. We tested the physiologic importance of CFTR-mediated nucleotide release in vivo by directly measuring levels of ATP and UTP in nasal airway surface liquid from normal and CF subjects. Because these basal nucleotide levels reflect the net activities of nucleotide release and metabolic pathways, we also measured constitutive rates of nucleotide release and metabolism on well-differentiated normal and CF airway cultures in vitro. The measurement of ATP release rates were paralleled by in vivo studies employing continuous nasal perfusion in normal and CF subjects. Finally, the regulation of ATP release by isoproterenol and methacholine-stimulated submucosal gland secretion was tested. These studies revealed that steady-state ATP and UTP levels were similar in normal (470 ± 131 nM and 37 ± 7 nM, respectively) and CF (911 ± 199 nM and 33 ± 12 nM, respectively) subjects. The rates of both ATP release and metabolism were also similar in normal and CF airway epithelia both in vitro and in vivo. Airway submucosal glands did not secrete nucleotides, but rather, secreted a soluble nucleotidase in response to cholinergic stimuli. The concentration of ATP in airway surface liquid is in a range that is relevant for the activation of airway nucleotide receptors. However, despite this finding that suggests endogenous nucleotides may be important for the regulation of mucociliary clearance, our data do not support a role for CFTR in regulating extracellular nucleotide concentrations on airway surfaces.

Mouse nasal airways are often used for the assessment of both reporter and cystic fibrosis transmembrane conductance regulator (CFTR) gene transfer to respiratory epithelia. However, the mouse nasal cavity is lined by both olfactory (OE) and respiratory epithelium (RE). Previous gene transfer studies have suggested that OE may be more efficiently transduced by adenoviral vectors than RE. However, to provide data pertinent to CFTR gene transfer in humans, measurements of CFTR function in mice by transepithelial potential difference (TPD) should be directed towards respiratory rather than olfactory epithelium. We report a new technique to mark the position of the TPD sensing cannula tip in the mouse nasal cavity that permitted us to correlate TPD measurements with epithelial cell type. Using this technique, we found TPD values did not discriminate between respiratory and olfactory epithelia. We next assessed relationships between anatomic regions accessed by the TPD cannula and epithelial type. The frequently used insertion depth of approximately 5 mm from the nose tip predominantly recorded the TPD from anterior dorsal olfactory epithelium. Measurement of the TPD of respiratory epithelium in our study was maximized by insertion of the TPD cannula probe to 2.5 mm depth. Because TPD measurements are not sensitive to epithelial type, adequate control of position and TPD catheter insertion depth are required to ensure accurate estimation of CFTR gene transfer into the target RE in the mouse nasal cavity.

We used a replication defective human lentiviral (HIV) vector encoding the lacZ cDNA and pseudotyped with the vesicular stomatitis virus (VSV) glycoprotein (G) to evaluate the utility of this vector system in airway epithelia. In initial studies, apical application of vector to polarized well differentiated human airway epithelial cell cultures produced minimal levels of transgene expression whereas basolateral application of vector enhanced levels of transduction approximately 30-fold. Direct in vivo delivery of HIV vectors to the nasal epithelium and tracheas of mice failed to mediate gene transfer, but injury with sulfur dioxide (SO2) before vector delivery enhanced gene transfer efficiency to the nasal epithelium of both mice and rats. SO2 injury also enhanced HIV vector-mediated gene transfer to the tracheas of rodents. These data suggest that SO2 injury increases access of vector to basal cells and/or the basolateral membrane of airway surface epithelial cells. Quantification of gene transfer efficiency in murine tracheas demonstrated that transduction was more efficient when vector was delivered on the day of exposure (7.0%, n = 4) than when vector was delivered on the day after SO2 exposure (1.7%, n = 4).

We have developed a system for the targeted delivery of adeno-associated virus (AAV) vectors. Targeting is achieved via a bispecific F(ab')2 antibody that mediates a novel interaction between the AAV vector and a specific cell surface receptor expressed on human megakaryocytes. Targeted AAV vectors were able to transduce megakaryocyte cell lines, DAMI and MO7e, which were nonpermissive for normal AAV infection, 70-fold above background and at levels equivalent to permissive K562 cells. Transduction was shown to occur through the specific interaction of the AAV vector-bispecific F(ab')2 complex and cell-associated targeting receptor. Importantly, targeting appeared both selective and restrictive as the endogenous tropism of the AAV vector was significantly reduced. Binding and internalization through the alternative receptor did not alter subsequent steps (escape from endosomes, migration to nucleus, or uncoating) required to successfully transduce target cells. These results demonstrate that AAV vectors can be targeted to a specific cell population and that transduction can be achieved by circumventing the normal virus receptor.

The Sf9 insect Spodoptora frugiperda cell line was used for heterologous expression of the cloned human cystic fibrosis transmembrane conductance regulator (CFTR) cDNA, or the cloned beta-galactosidase gene, using the baculovirus Autographa califonica as the infection vector. Using application of the patch-clamp technique, evidence for functional expression of CFTR was obtained according to the following three criteria. Firstly, whole-cell currents recorded 2 days after infection with CFTR revealed a statistically significant increase of membrane conductance, approximately 25 times above that of mock-infected control cells, with the reversal potential of the major current component being governed by the chloride equilibrium potential (ECl). Secondly, in contrast to uninfected cells and cells infected with beta-galactosidase, the membrane conductance to chloride of CFTR-injected cells was stimulated by cytosolic adenosine 3',5'-cyclic monophosphate (cAMP), which was raised by exposing the cells to 10 microM forskolin. Thirdly, recordings of currents through single channels in excised outside-out membrane patches of CFTR-infected cells revealed channels which were clearly different from the native insect chloride channel. Excised outside-out patches of CFTR-infected and forskolin-stimulated cells exhibited wave-like gating kinetics of well-resolved current transitions. All-point Gaussian distributions revealed contributions from several (five to nine) identical channels. Such channels, in excised outside-out patches, studied with a pipette [Cl-] = 40 mM and a bath [Cl-] = 150 mM, rectified the current in agreement with simple electrodiffusion and with a single-channel Goldman-Hodgkin-Katz permeability, PCl = 1. 34 x 10(-14) +/- 0.23 x 10(-14 )cm3/s (n = 5), corresponding to a physiological single-channel conductance of 2.8 +/- 0.5 pS (VM = ECl) and a limiting conductance, gamma150/150, = 7.7 +/- 1.3 pS ([Cl-]Bath = [Cl-]Cell = 150 mM). Currents recorded from multichannel excised outside-out patches could shift from the above mode of resolvable unitary conductance transitions to one which was too fast to reveal the dwell-times of closed and open states. During periods characterized by noisy currents, the variance (sigma2) of current fluctuations about their stationary mean value depicted a U-shaped function of membrane potential, with a minimum value at a pipette potential where the chloride current was shown to be zero. Thus, it can be concluded that the current fluctuations are caused by fast gating of channels specific for chloride ions. Switching back and forth between the two gating modes of clusters of chloride channels occurred from moment to moment in excised patches when the membrane potential was held at a constant value indicating cooperative gating as a result of interaction between neighbouring chloride channels.

The species-rich fynbos of the southern Langeberg Mountains, South Africa was studied along three transects (a) to evaluate the compatibility of a floristic classification of the southern Langeberg vegetation with a fynbos biome-wide structural classification of mountain vegetation, (b) to describe the environmental gradients to which the vegetation responds and (c) to investigate the relationship between the vegetation and the abiotic environmental variables which determine the pattern of distribution of the fynbos communities on the southern Langeberg.

THE success of adenoviral vectors for gene therapy of lung disease in cystic fibrosis (CF) depends on efficient transfer of the complementary DNA encoding the correct version of the cystic fibrosis transmembrane regulator (CFTR) to the affected columnar epithelial cells lining the airways of the lung. Pre-clinical studies in vitro suggest that low doses of adenovirus vectors carrying this CFTR cDNA can correct defective Cl− transport in cultured human CF airway epithelia1. Here we use mice carrying the disrupted CF gene2 to test the efficacy of this transfer system in vivo. We find that even repeated high doses can only partially (50%) correct the CF defect in Cl− transport in vivo and do not correct the Na+ transport defect at all. We investigated this discrepancy between the in vivo and in vitro transfer efficiency using CF mouse and human samples, and found that it reflects a difference in the susceptibility to adenovirus-5 transduction of the epithelial cell types dosed in vivo (columnar) and in vitro (basal-cell-like). These studies indicate that more efficient adenoviral gene-transfer vectors and/or refinement of dosing strategies are needed for therapy of CF lung disease.

We present the full two-loop four-graviton amplitudes in N = 4, 5, 6 supergravity. These results were obtained using the double-copy structure of gravity, which follows from the recently conjectured color-kinematics duality in gauge theory. The two-loop four-gluon scattering amplitudes in N = 0, 1, 2 supersymmetric gauge theory are a second essential ingredient. The gravity amplitudes have the expected infrared behavior: the two-loop divergences are given in terms of the squares of the corresponding one-loop amplitudes. The finite remainders are presented in a compact form. The finite remainder for N = 8 supergravity is also presented, in a form that utilizes a pure function with a very simple symbol.

In cystic fibrosis (CF), numerous epithelial cell functions are abnormal, including Cl- conductance, sodium absorption, mucin sulphation and enzyme secretion. Although the CF gene product, the cystic fibrosis transmembrane conductance regulator (CFTR), functions as a small linear Cl- channel, it is difficult to attribute such pleiotropic disease manifestations solely to a defect in Cl- conductance. This has led to speculation that CFTR regulates the activity of other proteins. One possible example is the protein kinase A activation of outward rectifying Cl- channels (ORCC), which is defective in membrane patches excised from CF cells. Whether CFTR regulates the activity of an independent anion channel is debatable, because ORCC occur exclusively in excised membrane patches and could be an excision-induced molecular derivative of CFTR. 'Knockout' mice that lack CFTR provide a means to define the relationship between CFTR and ORCC. Here we report that ORCC are present in CFTR(-/-) mouse nasal epithelial cells and thus cannot be a derivative of the CFTR molecule. Also ORCC were regulated by protein kinase A in membrane patches from normal but not CFTR(-/-) cells. These observations are the first, to our knowledge definitive demonstration that CFTR regulates the activity of another protein.

An important issue for in vivo gene therapy for cystic fibrosis (CF) is the percentage of cells within the CF airway that will require correction. In this study, we mixed populations of a CF airway cell line expressing either the normal cystic fibrosis transmembrane conductance regulator (CFTR) cDNA (corrected cells) or a reporter gene in defined percentages. As few as 6–10% corrected cells within an epithelial sheet generated Cl− transport properties similar to sheets comprised of 100% corrected cells. Cell–cell coupling may serve as the mechanism for amplification of the functional effects of corrected cells. These data suggest that in vivo correction of all CF airway cells may not be mandatory.

Background Defects in airway mucosal defense, including decreased mucus clearance, contribute to the pathogenesis of human chronic obstructive pulmonary diseases. Scnn1b-Tg mice, which exhibit chronic airway surface dehydration from birth, can be used as a model to study the pathogenesis of muco-obstructive lung disease across developmental stages. To identify molecular signatures associated with obstructive lung disease in this model, gene expression analyses were performed on whole lung and purified lung macrophages collected from Scnn1b-Tg and wild-type (WT) littermates at four pathologically relevant time points. Macrophage gene expression at 6 weeks was evaluated in mice from a germ-free environment to understand the contribution of microbes to disease development. Results Development- and disease-specific shifts in gene expression related to Scnn1b over-expression were revealed in longitudinal analyses. While the total number of transgene-related differentially expressed genes producing robust signals was relatively small in whole lung (n = 84), Gene Set Enrichment Analysis (GSEA) revealed significantly perturbed biological pathways and interactions between normal lung development and disease initiation/progression. Purified lung macrophages from Scnn1b-Tg mice exhibited numerous robust and dynamic gene expression changes. The expression levels of Classically-activated (M1) macrophage signatures were significantly altered at post-natal day (PND) 3 when Scnn1b-Tg mice lung exhibit spontaneous bacterial infections, while alternatively-activated (M2) macrophage signatures were more prominent by PND 42, producing a mixed M1-M2 activation profile. While differentially-regulated, inflammation-related genes were consistently identified in both tissues in Scnn1b-Tg mice, there was little overlap between tissues or across time, highlighting time- and tissue-specific responses. Macrophages purified from adult germ-free Scnn1b-Tg mice exhibited signatures remarkably similar to non-germ-free counterparts, indicating that the late-phase macrophage activation profile was not microbe-dependent. Conclusions Whole lung and pulmonary macrophages respond independently and dynamically to local stresses associated with airway mucus stasis. Disease-specific responses interact with normal developmental processes, influencing the final state of disease in this model. The robust signatures observed in Scnn1b-Tg lung macrophages highlight their critical role in disease pathogenesis. These studies emphasize the importance of region-, cell-type-, and time-dependent analyses to fully dissect the natural history of disease and the consequences of disease on normal lung development. Electronic supplementary material The online version of this article (doi:10.1186/1471-2164-15-726) contains supplementary material, which is available to authorized users.

The Symposium on the Management of Geodetic Data was held in Copenhagen in August, 1981. Many geodesists expect the issues of data management to be the next major problem area in geodesy. This Symposium was the first organized attempt to understand these issues and to share experiences.

The volume and composition of airway surface liquid, or “secretions”, is in part regulated by active ion transport mechanisms located in airway epithelia. These transport processes generate transepithelial electric potential differences (PDs) that can be measured in vivo. Specific identification and quantitation of transported ion species across respiratory epithelia require in vitro studies employing excised specimens. Recent studies have indicated that active Na+ absorption from airway lumen to the interstitium is the dominant active ion flow in the proximal airways of most mammalian species. This transport process is sensitive to both an inhibitor of Na+ entry into cells, amiloride, and the Na-K-ATPase inhibitor, ouabain. Respiratory epithelia from subjects with cystic fibrosis exhibit at least three abnormalities in proximal respiratory epithelial function: 1) a raised magnitude of transepithelial PD; 2) both absolutely and disproportionately greater reductions of PD after amiloride superfusion; 3) reduced permeability to Cl−. It is postulated that abnormalities in active ion transport activities of CF airway epithelia contribute to the abnormal airway secretions that characterize CF disease of the lung.

Recent studies have identified abnormalities in Cl- permeation across two target cystic fibrosis (CF) epithelia (sweat duct and respiratory epithelium). In the present study, anion conductances of red blood cells (RBCs) and peripheral blood lymphocytes (PBLs) from CF and normal subjects were estimated and compared. For RBCs, the valinomycin-induced rate constant for K+ loss (PK+) was taken as an index of PCl-. For PBLs, the secondary volume increase after gramicidin pretreatment and hypotonic (0.67 X isotonic) stress was used to estimate PCl-. The Cl- permeabilities of RBCs and PBLs from CF and control subjects were comparable. These findings suggest that the abnormality in PCl- reported for CF sweat ductal and respiratory epithelia is not expressed in circulating blood elements.

Probability learning to escape from shock was investigated in 36 female albino rats. The independent variable was the intensity of shock. All Ss were run in a T-maze using a correction procedure. One side of the T, (A1), was shock-free with probability, π =.667 while the other (A2) side was shock-free with probability (1 - π) =.333. The major findings were: (a) p(A1) exceeded π increasingly with increasingly severe shock, (b) positive recency was present throughout training and (c) response speed increased with increasing shock levels and was greater to the A1 than the A2 side.

Pulmonary epithelium changes after birth from Cl− secretion to Na+ absorption. To evaluate this transition, the maximal potential difference (PD) and the voltage response to superfusion with 10−5 M amiloride (Am), an inhibitor of Na+ absorption, were recorded between a Ringer perfused bridge placed on the nasal mucosa and a subcutaneous reference electrode. The PD was sequentially measured during the first 72 hrs of life across the nasal epithelium of healthy term neonates, healthy preterm neonates (29.7±0.3wks). neonates (30.2± 1.2wks) with Respiratory Distress Syndrome (RDS), and neonates (37.6± l.lwks) with Transient Tachypnea of the Newborn (TTNB). PDs (mean±SEM) and Am inhibition (%; at

Cystic fibrosis (CF) patients have an increased nasal transepithelial potential difference (PD) which reflects an increased Na+ absorption across a relatively Cl− impermeable membrane. To evaluate respiratory epithelial function in CF neonates, the maximal PD and the voltage response to superfusion of 10−5M amiloride (Am), an inhibitor of Na+ transport, were recorded between a Ringer perfused bridge on the nasal mucosa and a reference electrode in the subcutaneous space. We studied two term CF neonates presenting with meconium ileus (MI) and compared the results to 15 term healthy neonates including 1 obligate heterozygote (OH) for CF, and 12 term disease control (DC) neonates including 2 with ileal atresia, 2 with meconium aspiration, 1 with pneumonia, and 7 with Transient Tachypnea of the Newborn. Both neonates with MI had raised sweat Cl− values (x = 110meq/l) at 2 mo. The CF neonates had higher PDs than normal or disease controls (fig). Superfusion with Am induced a 72% reduction in PD in the CF neonates as compared to healthy (40.0 ± 3.7%) and disease (41.0 ± 2.6%) neonates. Also the neonatal PDs are comparable to values in older infants (2-24mo) where a similar PD pattern is present (fig). Moreover, the PD and Am response in CF neonates are similar to older (>6yr) CF children and adults (-64.9.+9.3mV; 77.7±1.8%, n=51). These results suggest that: (1) nasal epithelial dysfunction is present in CF patients shortly after birth, and (2) the nasal PD may be a diagnostic adjunct to the sweat test in the early diagnosis of CF.