bluuebunny/crossref_metadata_2025 huggingface dataset:
Reviewing Biosphere Reserves globally: effective conservation action or bureaucratic label?
Authors: Coetzer Kaera L. , Witkowski Edward T. F. , Erasmus Barend F. N.
Published: May 2013

The Biosphere Reserve (BR) model of UNESCO's Man and the Biosphere Programme reflects a shift towards more accountable conservation. Biosphere Reserves attempt to reconcile environmental protection with sustainable development; they explicitly acknowledge humans, and human interests in the conservation landscape while still maintaining the ecological values of existing protected areas. Conceptually, this model is attractive, with 610 sites currently designated globally. Yet the practical reality of implementing dual ‘conservation’ and ‘development’ goals is challenging, with few examples successfully conforming to the model's full criteria.

Here, we review the history of Biosphere Reserves from first inception in 1974 to the current status quo, and examine the suitability of the designation as an effective conservation model. We track the spatial expansion of Biosphere Reserves globally, assessing the influence of the Statutory Framework of the World Network of Biosphere Reserves and Seville strategy in 1995, when the BR concept refocused its core objectives on sustainable development. We use a comprehensive range of case studies to discuss conformity to the Programme, the social and ecological consequences associated with implementation of the designation, and challenges in aligning conservation and development. Given that the ‘Biosphere Reserve’ label is a relatively unknown designation in the public arena, this review also provides details on popularising the Biosphere Reserve brand, as well as prospects for further research, currently unexploited, but implicit in the designation.
Phenotypic plasticity in a generalist insect herbivore with the combined use of direct and indirect cues
Authors: Sandre Siiri‐Lii , Kaasik Ants , Eulitz Ute , Tammaru Toomas
Published: May 2013

Ultimate causes of phenotypic plasticity in visual appearance are frequently related to increasing the degree of crypsis in a way specific to the environment. The cues used to elicit such plastic responses may be both direct (i.e. straightforward background matching) as well as indirect. In the latter case, cues other than the visual signals from of the environment are used to predict the phenotype best corresponding to the particular situation. On the basis of a series of laboratory experiments we show that the remarkable variability in the visual appearance of the larvae of the geometrid mothEmaturga atomaria, though genetically based in part, involves a substantial environmental component. Using multiple correspondence analysis, we transformed the multidimensional variation in colour and pattern into two dimensions interpretable as patterning and darkness. Plastic changes in the darkness of the larvae were elicited by direct cues: the larvae were darker when reared on dark host‐plants. Host‐specific degree of patterning was also induced in absolute darkness which indicates the use of an indirect cue. This was unexpected because the study species is broadly polyphagous, and thus not likely to have evolved adaptations specific to particular host‐plant species. Indeed, the larvae ofE. atomariaoriginating from geographic populations using different host‐plants showed analogous plastic responses which indicates that the link between the indirect cue and visual appearance of the host needs not to be specific to plant species. In an additional experiment, we showed that surface roughness is a likely candidate to serve as the proximate cue for determination of some pattern elements, a case not reported for insect larvae earlier.
High‐resolution habitat suitability modelling can improve conservation of vulnerable marine ecosystems in the deep sea
Authors: Rengstorf Anna M. , Yesson Chris , Brown Colin , Grehan Anthony J.
Published: May 2013

Aim

The distribution of vulnerable marine ecosystems in the deep sea is poorly understood. This has led to the emergence of modelling methods to predict the occurrence of suitable habitat for conservation planning in data‐sparse areas. Recent global analyses for cold‐water corals predict a high probability of occurrence along the slopes of continental margins, offshore banks and seamounts in the north‐eastern Atlantic, but tend to overestimate the extent of the habitat and do not provide the detail needed for finer‐scale assessments and protected area planning. Using Lophelia pertusa reefs as an example, this study integrates multibeam bathymetry with a wide range of environmental data to produce a regional high‐resolution habitat suitability map relevant for marine spatial planning.

Location

Irish continental margin (extended continental shelf claim).

Methods

Maximum entropy modelling was used to predict L. pertusa reef distribution at a spatial resolution of 0.002°. Coral occurrences were assembled from public databases, publications and video footage, and filtered for quality. Environmental predictor variables were produced by re‐sampling of global oceanographic data sets and a regional ocean circulation model. Multi‐scale terrain parameters were computed from multibeam bathymetry.

Results

Suitable habitat was predicted on mound features and in canyon areas along a narrow band following the slopes of the Irish continental margin, the Rockall Bank and the Porcupine Bank. Standard deviation of the seabed slope (54%), temperature (28%) and bottom shear stress (9%) were the most important variables to predict coral distribution.

Main conclusions

This is the first regional coral habitat suitability modelling study to incorporate full coverage multibeam bathymetry in the deep sea. The use of high‐resolution environmental data and quality‐controlled distribution data significantly reduces habitat overestimation demonstrated by global‐scale analyses and produces detailed maps to support marine protected area network design. The strong response of the corals to local‐scale terrain variability highlights the need to protect the seabed from anthropogenic impacts that may reduce its complexity, such as bottom trawling.
Structural and ultrastructural features of the agouti tongue (Dasyprocta aguti Linnaeus, 1766)
Authors: Ciena Adriano Polican , Bolina Cristina de Sousa , de Almeida Sonia Regina Yokomizo , Rici Rose Eli Grassi , de Oliveira Moacir Franco , Silva Marcelo Cavenaghi Pereira da , Miglino Maria Angélica , Watanabe Ii‐sei
Published: May 2013

The agouti (Dasyprocta aguti Linnaeus, 1766) is a wild rodent belonging to the family Dasyproctidae that is found throughout Brazil and feeds on fruits and seeds. The aim of the present study was to describe the following features of the tongue of agouti: its morphological structures, the three‐dimensional characteristics of the lingual papillae surface, the connective tissue cores (CTCs) and the epithelial cell ultrastructure. Four types of papillae were observed on the dorsal surface of the tongue with a triangular shape: filiform, fungiform, foliate and vallate. Filiform papillae were distributed throughout the tongue surface, and removal of the epithelial surface revealed conical CTCs and multifilaments. Fungiform papillae were observed in the rostral and middle regions, whereas foliate papillae developed in pairs on the lateral margin of the caudal region. Removal of the epithelium in these regions revealed CTCs with parallel laminar conformation. Vallate papillae were arranged in a V‐shape in the caudal region, and their CTCs ranged in shape from elongate to ovoid. The ultrastructural components of the dorsal epithelium were the basal, spinous, granular and keratinised layers. A broad area with cytoplasmic projections was identified in the interface region between the lamina propria and the basal layer. Flattened cells with intermediate filaments were observed in the transitional region between spinous and granular layers. The keratinised layer was composed of superimposed epithelial cells where desmosomes and cell‐surface microridges were observed. These structural features, including the three‐dimensional aspects of the lingual papillae, the CTCs and the epithelial ultrastructure, indicate that when compared with other animals, particularly other rodent species, the morphological features of the tongue of agouti are relatively well developed, especially regarding foliate and vallate papillae.
Efficacy and safety of spontaneous ventilation technique using dexmedetomidine for rigid bronchoscopic airway foreign body removal in children
Authors: Cai Yirong , Li Wenxian , Chen Kaizheng
Published: May 2013

Background

In children, removal of an airway foreign body is usually performed by rigid bronchoscopy under general anesthesia. Debate continues regarding the respiratory mode (spontaneous or controlled ventilation) and appropriate anesthetic drugs. Dexmedetomidine has several desirable pharmacologic properties and appears to be a useful agent for airway surgeries.

Objectives

This study evaluates the efficacy of spontaneous ventilation (SV) technique using dexmedetomidine for bronchoscopic removal of foreign bodies in children.

Methods

Eighty pediatric patients undergoing rigid bronchoscopy for airway foreign body removal were randomly divided into two groups. In the SV group, dexmedetomidine (4 μg∙kg−1) and topical lidocaine (3–5 mg∙kg−1) were administered and the patients were breathing spontaneously throughout the procedure. In the manual jet ventilation (MJV) group, anesthesia was induced with fentanyl (2 μg∙kg−1), propofol (3–5 mg∙kg−1), and succinylcholine (1 mg∙kg−1), and MJV was performed.

Results

The success rates of foreign body removal, the incidence of body movement and other perioperative adverse events, and hemodynamic changes were similar between the two groups. The SV patients required longer stays in the postanesthesia care unit (P < 0.01) but experienced less coughing (P = 0.029) in the recovery room.

Conclusion

Dexmedetomidine may provide appropriately deep anesthesia and ideal conditions for rigid bronchoscopic airway foreign body removal without respiratory depression or hemodynamic instability.
Ground State and Geometrically Distinct Solitons of Discrete Nonlinear Schrödinger Equations with Saturable Nonlinearities
Authors: Chen Guanwei , Ma Shiwang
Published: May 2013

We study the discrete nonlinear equation

urn:x-wiley:00222526:sapm12016:equation:sapm12016-math-0001where (the spectrum of L) and is asymptotically linear as for all . We obtain the existence of ground state solitons and the existence of infinitely many pairs of geometrically distinct solitons of this equation. Our method is based on the generalized Nehari manifold method developed recently by Szulkin and Weth. To the best of our knowledge, this technique has not been used for discrete equations with saturable nonlinearities.
Experimental Study on Aerodynamics of Microelectromechanical Systems Based Single-Crystal-Silicon Microscale Supersonic Nozzle
Authors: Namura Moriaki , Toriyama Toshiyuki
Published: May 2013

In this paper, the design, microfabrication, and direct measurement of the static pressure distribution for the aerodynamics of a single-crystal-silicon microscale supersonic nozzle are described. The microscale supersonic nozzle has a convergent–divergent section and a throat area of 100μm × 300μm. The microscale supersonic nozzle was fabricated by silicon bulk micromachining technology. The degree of the rarefaction of nozzle flow was determined by the Knudsen number (Kn). The operation envelope that determines whether the continuum or rarefied flow assumption is appropriate can be expressed as a function of Kn and related parameters. The effect of nonadiabatic operation on microscale nozzle flow was investigated on the basis of wall heat transfer. These physical correlations were taken into account for the classical Shapiro's equations to analyze the microscale nozzle flow aerodynamics (Shapiro, 1953, The Dynamics and Thermodynamics of Compressible Fluid Flow, Ronald, New York, Chap. 7,8; Greitzer et al., 2006, Internal Flow, Cambridge University, Cambridge, UK, Chap. 2,10). Furthermore, the solutions of Shapiro's equations were compared with the experimental results by the authors and other research institutions in order to demonstrate the validity of the proposed aerodynamics design concept for microscale continuum flow.
Simplified Serum Neutralization Test Based on Enhanced Green Fluorescent Protein-Tagged Classical Swine Fever Virus
Authors: Li Yongfeng , Shen Liang , Sun Yuan , Yuan Jin , Huang Junhua , Li Chao , Li Su , Luo Yuzi , Qiu Hua-Ji
Published: May 2013

The neutralization immunofluorescence test (NIFT), currently used for detecting neutralizing antibodies (NAbs) against classical swine fever virus (CSFV), is time-consuming. Here, a simplified neutralization test based on enhanced green fluorescent protein (EGFP)-tagged CSFV (EGFP-NT) was developed for direct detection of anti-CSFV NAbs without immunostaining. The relative sensitivity and specificity between EGFP-NT and NIFT or blocking enzyme-linked immunosorbent assay (ELISA) were both 100%. The NAb titers by EGFP-NT and the blocking rates by blocking ELISA showed a good correlation.
Nonconserved Tryptophan 38 of the Cell Surface Receptor for Subgroup J Avian Leukosis Virus Discriminates Sensitive from Resistant Avian Species
Authors: Kučerová Dana , Plachý Jiří , Reinišová Markéta , Šenigl Filip , Trejbalová Kateřina , Geryk Josef , Hejnar Jiří
Published: May 2013

Subgroup J avian leukosis virus (ALV-J) is unique among the avian sarcoma and leukosis viruses in using the multimembrane-spanning cell surface protein Na
+
/H
+
exchanger type 1 (NHE1) as a receptor. The precise localization of amino acids critical for NHE1 receptor activity is key in understanding the virus-receptor interaction and potential interference with virus entry. Because no resistant chicken lines have been described until now, we compared the NHE1 amino acid sequences from permissive and resistant galliform species. In all resistant species, the deletion or substitution of W38 within the first extracellular loop was observed either alone or in the presence of other incidental amino acid changes. Using the ectopic expression of wild-type or mutated chicken NHE1 in resistant cells and infection with a reporter recombinant retrovirus of subgroup J specificity, we studied the effect of individual mutations on the NHE1 receptor capacity. We suggest that the absence of W38 abrogates binding of the subgroup J envelope glycoprotein to ALV-J-resistant cells. Altogether, we describe the functional importance of W38 for virus entry and conclude that natural polymorphisms in NHE1 can be a source of host resistance to ALV-J.
Colpocephaly in adults
Authors: Esenwa Charles C , Leaf David E
Published: May 2013

Colpocephaly is a congenital abnormality in the ventricular system of the brain. The radiological diagnosis is usually made in the perinatal period and later presages intellectual disability. Adult cases of newly diagnosed colpocephaly have only rarely been reported. We have studied an adult with massive colpocephaly who is an otherwise functional woman. The diagnosis should be considered in patients with ventriculomegaly disproportionately affecting the occipital horns and must be differentiated from the more common form of adult ventriculomegaly—idiopathic normal pressure hydrocephalus (NPH).
A new perspective on MOND
Authors: Bugg D.V.
Published: May 2013

A novel interpretation of modified Newtonian dynamics (MOND) is presented. For galactic data, in addition to Newtonian acceleration, there is an attractive acceleration peaking at Milgrom’s parameter, a0. The peak lies within experimental error where a0 = cH0/2π; H0 is the present-time value of the Hubble constant, and c the velocity of light. The physical interpretation of this relation and its connection to dark energy are discussed.
Insulin directly stimulates VEGF-A production in the glomerular podocyte
Authors: Hale L. J. , Hurcombe J. , Lay A. , Santamaría B. , Valverde A. M. , Saleem M. A. , Mathieson P. W. , Welsh G. I. , Coward R. J.
Published: May 2013

Podocytes are critically important for maintaining the integrity of the glomerular filtration barrier and preventing albuminuria. Recently, it has become clear that to achieve this, they need to be insulin sensitive and produce an optimal amount of VEGF-A. In other tissues, insulin has been shown to regulate VEGF-A release, but this has not been previously examined in the podocyte. Using in vitro and in vivo approaches, in the present study, we now show that insulin regulates VEGF-A in the podocyte in both mice and humans via the insulin receptor (IR). Insulin directly increased VEGF-A mRNA levels and protein production in conditionally immortalized wild-type human and murine podocytes. Furthermore, when podocytes were rendered insulin resistant in vitro (using stable short hairpin RNA knockdown of the IR) or in vivo (using transgenic podocyte-specific IR knockout mice), podocyte VEGF-A production was impaired. Importantly, in vivo, this occurs before the development of any podocyte damage due to podocyte insulin resistance. Modulation of VEGF-A by insulin in the podocyte may be another important factor in the development of glomerular disease associated with conditions in which insulin signaling to the podocyte is deranged.
Saccade suppression exerts global effects on the motor system
Authors: Wessel Jan R. , Reynoso H. Sequoyah , Aron Adam R.
Published: May 2013

Stopping inappropriate eye movements is a cognitive control function that allows humans to perform well in situations that demand attentional focus. The stop-signal task is an experimental model for this behavior. Participants initiate a saccade toward a target and occasionally have to try to stop the impending saccade if a stop signal occurs. Prior research using a version of this paradigm for limb movements (hand, leg) as well as for speech has shown that rapidly stopping action leads to apparently global suppression of the motor system, as indexed by the corticospinal excitability (CSE) of task-unrelated effectors in studies with transcranial magnetic stimulation (TMS) of M1. Here we measured CSE from the hand with high temporal precision while participants made saccades and while they successfully and unsuccessfully stopped these saccades in response to a stop signal. We showed that 50 ms before the estimated time at which a saccade is successfully stopped there was reduced CSE for the hand, which was task irrelevant. This shows that rapidly stopping eye movements also has global motor effects. We speculate that this arises because rapidly stopping eye movements, like skeleto-motor movements, is possibly achieved via input to the subthalamic nucleus of the basal ganglia, with a putatively broad suppressive effect on thalamocortical drive. Since recent studies suggest that this suppressive effect could also impact nonmotor representations, the present finding points to a possible mechanistic basis for some kinds of distractibility: abrupt-onset stimuli will interrupt ongoing processing by generating global motor and nonmotor effects.
Avidity Studies in Anisakis simplex-Associated Allergic Diseases
Authors: Cuéllar Carmen , Valls Ana , de Frutos Consolación , Rodero Marta , Daschner Alvaro
Published: May 2013

Gastroallergic anisakiasis (GAA) and Anisakis-sensitization-associated chronic urticaria (CU+) differ with respect to specific IgE levels. We hypothesised different immunoglobulin avidities in both entities as well as their dependence on TI and fish consumption. 16 patients with GAA and 17 patients with CU+ were included, and immunoglobulin levels were analysed by CAP (Phadia). IgE and IgG avidity indexes (AvIgE and AvIgG, resp.) were also determined. IgG avidity was higher in GAA than in CU+ (P=0.035), whereas there was a tendency to lower IgE avidity in GAA (P=0.095). When analysing all patients, AvIgG was positively correlated with specific IgE, IgG, and IgG4 as well as total IgE (Rho between 0.66 and 0.71; P<0.002), but AvIgE was negatively correlated with specific IgE (Rho −0.57; P<0.001), specific IgG4 (Rho −0.38; P<0.05), and total IgE (Rho 0.66; P<0.001). In GAA, weekly fish consumption was positively associated with AvIgE (Rho 0.51; P=0.05). A multivariate regression showed that time interval was the main explaining factor for AvIgE in GAA. We could show a differential behaviour of immunoglobulin isotype avidities in both entities and their dependence on fish-eating habits as well as on the time elapsed to the last parasitic episode.
Involvement of MicroRNA in Microglia-Mediated Immune Response
Authors: Guedes J. , Cardoso A. L. C. , Pedroso de Lima M. C.
Published: May 2013

MicroRNAs (miRNAs) are an abundant class of small noncoding RNA molecules that play an important role in the regulation of gene expression at the posttranscriptional level. Due to their ability to simultaneously modulate the fate of different genes, these molecules are particularly well suited to act as key regulators during immune cell differentiation and activation, and their dysfunction can contribute to pathological conditions associated with neuroinflammation. Recent studies have addressed the role of miRNAs in the differentiation of progenitor cells into microglia and in the activation process, aiming at clarifying the origin of adult microglia cells and the contribution of the central nervous system (CNS) environment to microglia phenotype, in health and disease. Altered expression of several miRNAs has been associated with Alzheimer’s disease, multiple sclerosis, and ischemic injury, hence strongly advocating the use of these small molecules as disease markers and new therapeutic targets. This review summarizes the recent advances in the field of miRNA-mediated regulation of microglia development and activation. We discuss the role of specific miRNAs in the maintenance and switching of microglia activation states and illustrate the potential of this class of nucleic acids both as biomarkers of inflammation and new therapeutic tools for the modulation of microglia behavior in the CNS.
p-Moment Stability of Stochastic Differential Delay Systems with Impulsive Jump and Markovian Switching
Authors: Gao Lijun
Published: May 2013

This paper investigatesp-moment stability of the stochastic differential delay systems with impulsive jump and Markovian switching. Some stability criteria are obtained based on Lyapunov functional method and stochastic theory. It is shown that, even if all the subsystems governing the continuous dynamics without impulse are not stable, as impulsive and switching signal satisfies a dwell-time upper bound condition, impulses can stabilize the systems in thep-moment stability sense. The opposite situation is also developed for which all the subsystems governing the continuous dynamics arep-moment stable. The results can be easily applied to stochastic systems with arbitrarily large delays. The efficiency of the proposed results is illustrated by two numerical examples.
Design of Online Monitoring and Fault Diagnosis System for Belt Conveyors Based on Wavelet Packet Decomposition and Support Vector Machine
Authors: Li Wei , Wang Zewen , Zhu Zhencai , Zhou Gongbo , Chen Guoan
Published: May 2013

Belt conveyors are the equipment widely used in coal mines and other manufacturing factories, whose main components are a number of idlers. The faults of belt conveyors can directly influence the daily production. In this paper, a fault diagnosis method combining wavelet packet decomposition (WPD) and support vector machine (SVM) is proposed for monitoring belt conveyors with the focus on the detection of idler faults. Since the number of the idlers could be large, one acceleration sensor is applied to gather the vibration signals of several idlers in order to reduce the number of sensors. The vibration signals are decomposed with WPD, and the energy of each frequency band is extracted as the feature. Then, the features are employed to train an SVM to realize the detection of idler faults. The proposed fault diagnosis method is firstly tested on a testbed, and then an online monitoring and fault diagnosis system is designed for belt conveyors. An experiment is also carried out on a belt conveyor in service, and it is verified that the proposed system can locate the position of the faulty idlers with a limited number of sensors, which is important for operating belt conveyors in practices.
Investigations on the Outdoor Performance Characteristics of Multicrystalline Silicon Solar Cell and Module
Authors: Parthasarathy Sivakumar , Neelamegam P. , Thilakan P. , Tamilselvan N.
Published: May 2013

Multicrystalline silicon solar cell and its module with 18 cells connected in series were mounted on an inclined rack tilted 12° South positioned at latitude of 12.0107° and longitude of 79.856°. Corresponding solar irradiance was measured using an optical Pyranometer. Measured irradiance, open circuit voltage (), and short circuit current () values were analyzed. values of both the cell and module were found saturated at above the critical value of illuminations which were different from each other. The integrated daily efficiency for the cell and module were ~10.25% and ~9.39%, respectively, that were less than their respective standard test condition’s value. The reasons for this drop in efficiencies were investigated and reported.
Loss and Dysregulation of Th17 Cells during HIV Infection
Authors: Bixler Sandra L. , Mattapallil Joseph J.
Published: May 2013

Bacterial translocation across the damaged mucosal epithelium has emerged as a major paradigm for chronic immune activation observed during HIV infection. T helper 17 (Th17) cells are a unique lineage of T helper cells that are enriched in mucosal tissues and are thought to play a central role in protecting the integrity of the mucosal barrier and maintaining immune homeostasis at mucosal sites. Th17 cells are lost very early during the course of HIV infection, and their loss has been shown to correlate with bacterial translocation. Interestingly, Th17 cells are unable to completely recover from the early destruction even after successful antiretroviral therapy (ART). Here, we review some of the potential mechanisms for the loss and dysregulation of Th17 cells during HIV infection.
Release of Propolis Phenolic Acids from Semisolid Formulations and Their Penetration into the Human SkinIn Vitro
Authors: Žilius Modestas , Ramanauskienė Kristina , Briedis Vitalis
Published: May 2013

Antioxidant and free radical scavenging effects are attributed to phenolic compounds present in propolis, and when delivered to the skin surface and following penetration into epidermis and dermis, they can contribute to skin protection from damaging action of free radicals that are formed under UV and premature skin aging. This study was designed to determine the penetration of phenolic acids and vanillin into the human skinin vitrofrom experimentally designed vehicles. Results of the study demonstrated the ability of propolis phenolic acids (vanillic, coumaric, caffeic, and ferulic acids) and vanillin to penetrate into skin epidermis and dermis. The rate of penetration and distribution is affected both by physicochemical characteristics of active substances and physical structure and chemical composition of semisolid vehicle. Vanillin and vanillic acid demonstrated relatively high penetration through epidermis into dermis where these compounds were concentrated, coumaric and ferulic acids were uniformly distributed between epidermis and dermis, and caffeic acid slowly penetrated into epidermis and was not determined in dermis. Further studies are deemed relevant for the development of semisolid topically applied systems designed for efficient delivery of propolis antioxidants into the skin.
Orographic Drag Associated with Lee Waves Trapped at an Inversion
Authors: Teixeira Miguel A. C. , Argaín José Luis , Miranda Pedro M. A.
Published: May 2013

The drag produced by 2D orographic gravity waves trapped at a temperature inversion and waves propagating in the stably stratified layer existing above are explicitly calculated using linear theory, for a two-layer atmosphere with neutral static stability near the surface, mimicking a well-mixed boundary layer. For realistic values of the flow parameters, trapped-lee-wave drag, which is given by a closed analytical expression, is comparable to propagating-wave drag, especially in moderately to strongly nonhydrostatic conditions. In resonant flow, both drag components substantially exceed the single-layer hydrostatic drag estimate used in most parameterization schemes. Both drag components are optimally amplified for a relatively low-level inversion and Froude numbers Fr ≈ 1. While propagating-wave drag is maximized for approximately hydrostatic flow, trapped-lee-wave drag is maximized for l2a = O(1) (where l2 is the Scorer parameter in the stable layer and a is the mountain width). This roughly happens when the horizontal scale of trapped lee waves matches that of the mountain slope. The drag behavior as a function of Fr for l2H = 0.5 (where H is the inversion height) and different values of l2a shows good agreement with numerical simulations. Regions of parameter space with high trapped-lee-wave drag correlate reasonably well with those where lee-wave rotors were found to occur in previous nonlinear numerical simulations including frictional effects. This suggests that trapped-lee-wave drag, besides giving a relevant contribution to low-level drag exerted on the atmosphere, may also be useful to diagnose lee-rotor formation.
A critical study on the experimental determination of stiffness and viscosity of the human triceps surae by free vibration methods
Authors: París-García Federico , Barroso Alberto , Cañas José , Ribas Juan , París Federico
Published: May 2013

Muscles and tendons play an important role in human performance. Their mechanical behaviour can be described by analytical/numerical models including springs and dampers. Free vibration techniques are a widely used approach to the in vivo determination of stiffness and viscosity of muscle–tendon complexes involved in sport movements. By considering the data reported in the literature, it appears that the visco-elastic properties of the triceps surae muscle–tendon complexes are independent of the modality in which free vibration is induced as well as they do not depend on the composition of the population of subjects submitted to the experiments. This research will critically discuss this important aspect focussing in particular on two studies documented in the literature. For this purpose, two equipments will be developed to reproduce literature experiments under the assumption that the oscillating part of the body behaves as a single-degree-of-freedom system: The governing degree of freedom is associated with the vertical displacement of the lower leg or with the rotation of the foot around the ankle articulation. Unlike literature, measurements are now conducted on the same population of subjects in order to draw more general conclusions on the real equivalence of results and validity of the mechanical properties determined experimentally. Free vibration tests are accurately simulated by analytical models describing the response of each vibrating system. It is found that if the two measurement protocols are applied to the same population of individuals as it is done in this study, values of visco-elastic properties of muscle–tendon complexes extracted from experimental data are significantly different, the differences presenting a convincing consistency. This result is in contrast with the literature and confirms the need to evaluate results of free vibration techniques by taking homogeneous bases of comparison.
Effect of aspirin cessation before endoscopy in Japanese patients with low‐dose‐aspirin‐associated gastroduodenal mucosal injury
Authors: Ito Yoshitsugu , Sasaki Makoto , Noguchi Seiji , Yamaguchi Sumiharu , Okaniwa Noriko , Tanabe Atsushi , Noda Hisatsugu , Yanamoto Kenichiro , Tamura Yasuhiro , Kondo Yoshihiro , Masui Ryuta , Izawa Shinya , Iida Akihito , Mizuno Mari , Ogasawara Naotaka , Funaki Yasushi , Kasugai Kunio
Published: May 2013

Background

The incidence of upper gastrointestinal injury by low‐dose aspirin (LDA) has increased.

Objective

We aimed to clarify the risk factors and prevention strategies associated with LDA‐induced gastroduodenal ulcer in Japanese patients.

Methods

A retrospective study involving 284 LDA users who underwent oesophagogastroduodenoscopy between January and December 2010 were included. We investigated the patients’ clinical characteristics and endoscopic findings.

Results

Of 284 patients, 29 (10.2%) had gastro and/or duodenal ulcers. Male gender, peptic ulcer history, abdominal symptoms, half‐dose proton pump inhibitors (PPIs), complete‐dose PPIs, and nonsteroidal anti‐inflammatory drugs were significantly associated with LDA‐induced gastro and/or duodenal ulcers: odds ratio (95% confidence interval) 3.62 (1.06–12.27), 6.60 (1.84–23.62), 3.06 (1.12–8.40), 0.16 (0.03–0.94), 0.07 (0.01–0.61), and 9.68 (1.64–57.18), respectively. PPI significantly reduced gastric ulcers and/or duodenal ulcers (p  = 0.03). The modified Lanza score for gastric mucosal lesion in the LDA cessation group was significantly lower than in the LDA noncessation group (0.53 vs. 1.02; p  = 0.008).

Conclusions

Half‐dose PPIs as well as complete‐dose PPIs were effective for preventing LDA‐induced gastric and/or duodenal ulcers. The cessation of LDA before endoscopy may lead to an underestimation of LDA‐induced gastric injury.
Effect of nutritional factors on adherence to antiretroviral therapy among HIV-infected adults: a case control study in Northern Ethiopia
Authors: Berhe Negassie , Tegabu Desalegn , Alemayehu Mekuriaw
Published: May 2013

Background

Adherence to antiretroviral treatment is critical for suppression of viral replication, reduced destruction of CD4 cells, prevention of viral resistance, promotion of immune reconstitution and slowed disease progression. This study sought to determine the effect of nutritional factors on adherence to ART among HIV-infected adults on ART.

Methods

Matched case control study design (matched by age and sex) was employed. Data was collected from ART registration chart, pre-tested structured data extraction format, anthropometric measurements and by interview. Conditional logistic regression was used to compute the relevant associations among the variables by STATA version 10.

Results

From 174 paired subjects participated in the study 80 (46%) pair were males and 94 (54%) pair were females on ART for at least one year prior to the survey. The mean age (±SD) for the non-adherent was 38.4 ± 8.1years and for the adherent subjects was 38.5 ± 8.4 years. Malnutrition with BMI less than 18.5 Kg/m2 in the adherent group was 14 (8%) and that of the non-adherent group was 74 (42.5%) which was associated with non-adherence to ART (AOR 10.0, 95%CI 4.3 – 54.7). Inability to get enough and quality food was also associated with non-adherence to ART (AOR 2.1, 95%CI 1.1 – 11.5).

Conclusions

Malnutrition, inability to get enough and/or quality food and consumption pattern which is less than three meals per day were significantly associated with non-adherence to ART. Therefore, the capacity to effectively manage the food and nutrition implications of ART adherence is a critical factor in the success of antiretroviral therapy in resource limited settings.
barx1represses joints and promotes cartilage in the craniofacial skeleton
Authors: Nichols James T. , Pan Luyuan , Moens Cecilia B. , Kimmel Charles B.
Published: May 2013

The evolution of joints, which afford skeletal mobility, was instrumental in vertebrate success. Here, we explore the molecular genetics and cell biology that govern jaw joint development. Genetic manipulation experiments in zebrafish demonstrate that functional loss, or gain, of the homeobox-containing gene barx1 produces gain, or loss, of joints, respectively. Ectopic joints in barx1 mutant animals are present in every pharyngeal segment, and are associated with disrupted attachment of bone, muscles and teeth. We find that ectopic joints develop at the expense of cartilage. Time-lapse experiments suggest that barx1 controls the skeletal precursor cell choice between differentiating into cartilage versus joint cells. We discovered that barx1 functions in this choice, in part, by regulating the transcription factor hand2. We further show that hand2 feeds back to negatively regulate barx1 expression. We consider the possibility that changes in barx1 function in early vertebrates were among the key innovations fostering the evolution of skeletal joints.
miR-34b regulates multiciliogenesis during organ formation in zebrafish
Authors: Wang Lei , Fu Cong , Fan Hongbo , Du Tingting , Dong Mei , Chen Yi , Jin Yi , Zhou Yi , Deng Min , Gu Aihua , Jing Qing , Liu Tingxi , Zhou Yong
Published: May 2013

Multiciliated cells (MCCs) possess multiple motile cilia and are distributed throughout the vertebrate body, performing important physiological functions by regulating fluid movement in the intercellular space. Neither their function during organ development nor the molecular mechanisms underlying multiciliogenesis are well understood. Although dysregulation of members of the miR-34 family plays a key role in the progression of various cancers, the physiological function of miR-34b, especially in regulating organ formation, is largely unknown. Here, we demonstrate that miR-34b expression is enriched in kidney MCCs and the olfactory placode in zebrafish. Inhibiting miR-34b function using morpholino antisense oligonucleotides disrupted kidney proximal tubule convolution and the proper distribution of distal transporting cells and MCCs. Microarray analysis of gene expression, cilia immunostaining and a fluid flow assay revealed that miR-34b is functionally required for the multiciliogenesis of MCCs in the kidney and olfactory placode. We hypothesize that miR-34b regulates kidney morphogenesis by controlling the movement and distribution of kidney MCCs and fluid flow. We found that cmyb was genetically downstream of miR-34b and acted as a key regulator of multiciliogenesis. Elevated expression of cmyb blocked membrane docking of centrioles, whereas loss of cmyb impaired centriole multiplication, both of which resulted in defects in the formation of ciliary bundles. Thus, miR-34b serves as a guardian to maintain the proper level of cmyb expression. In summary, our studies have uncovered an essential role for miR-34b-Cmyb signaling during multiciliogenesis and kidney morphogenesis.
Developments in the chemistry and biochemistry of pectic and hemicellulosic polymers
Authors: Selvendran R. R.
Published: May 2013

Improved methods of isolation and analysis of cell walls from a range of plant tissues have shed new light on the structure of the constituent polymers, and have also helped to clarify some of the conflicting opinions on their mode of occurrence and association within the walls. The chemistry (and biochemistry) of pectic and hemicellulosic polymers in different types of plant organs is outlined, with particular emphasis on parenchymatous and immature tissues. The following aspects are discussed: (1) the mode of occurrence of arabinans, galactans and arabinogalactans, and the possible association of some of them with proteins; (2) the structural features of the esterified rhamnogalacturonans and associated neutral sugar residues in the pectic substances of middle lamellae and primary cell walls; (3) the occurrence of acidic xylans, acidic arabinoxylans, and acidic arabinoxylans in association with other polymers in the cell walls of cambial, suspension-cultured and parenchymatous tissues of dicotyledons; (4) evidence for the occurrence of small but significant amounts of xyloglucans in association with other polymers, and the occurrence of a range of xyloglucans in parenchymatous tissues; (5) evidence for the occurrence of phenolic ester and phenolic cross-linkages between the cell wall polymers of parenchymatous tissues of both dicotyledons and monocotyledons, particularly the association of hydroxycinnamic acids with some pectic substances; (6) the occurrence of proteoglycans and proteoglycan-polyphenol complexes and their relationship to the traditional hemicelluloses; and (7) some aspects of the non-cellulosic polymers of non-endospermic and endospermic seeds.
The Cytoskeleton Of The Early Drosophila Embryo
Authors: M. Warn R.
Published: May 2013

The organization and roles of the cytoskeleton are described for a complex developing system (the early Drosophila embryo) at a time when the basic embryonic plan is mapped out. This type of embryo shows a separation of mitosis from cytokinesis during the early stages of development. Most cells are only formed when a syncytium of ≈6000 nuclei are present. The functions of the cytoskeleton are considered for the process of nuclear migration (pre-blastoderm), which distributes the nuclei throughout the embryo and brings most of them close to the surface. They are also described for the subsequent mitoses of the syncytial blastoderm where the cortex and its well- developed cytoskeleton is reorganized into cell-like surface protrusions known as ‘caps’ or ‘buds’. A comparison is made of the very different cytoskeletal organization present during the cleavages that form the two cell types of early development (pole cell and blastoderm cell), together with information from mutations that affect various aspects of these cleavages via factors laid down during oogenesis.
Epithelial stem cells in vivo
Authors: Potten C. S. , Morris R. J.
Published: May 2013

Cellular topography within the highly polarized surface epithelia can be used to identify the location of the stem cells. In some instances, this can be quite precise and allows the characteristics of stem cells to be studied. Our current knowledge of the stem cell population in murine epidermis and small intestinal crypts is reviewed. In the epidermis, the stem cells would appear to make up about 10 % of the basal layer and are distributed towards the centre of the basal layer component of the epidermal proliferative unit. These cells have a long cell cycle and are probably the same cells that retain both tritiated thymidine and radioactively labelled carcinogens for long periods of time. This label retention permits the labelling of the putative stem cell compartment. Over recent years, there has been an accumulation of information indicating various types of heterogeneity within the basal layer, much of which can be interpreted in relation to cellular hierarchies. In the small intestine, cell positions can be fairly precisely identified and the stem cell zone identified. Complex modelling of a wide range of cell kinetic experiments suggests that each crypt contains between 4 and 16 steady state functional stem cells. Radiobiological experiments suggest that up to 32 cells may be capable of clonal regeneration. The repopulation of the clonogenic cell compartment has been determined and the doubling time measured to be 19•7h. Such studies should throw further light on the behaviour of stem cells and identify the timing of periods of increased and decreased cell proliferation (activation and suppression of controls).
Mitogenic signalling through the bombesin receptor: Role of a guanine nucleotide regulatory protein
Authors: Rozengurt Enrique , Fabregat Isabel , Coffer Arnold , Gil Joan , Sinnett-Smith James
Published: May 2013

Bombesin and structurally related peptides including gastrin releasing peptide (GRP) are potent mitogens for Swiss 3T3 cells. The early cellular and molecular responses elicited by bombesin and structurally related peptides have been elucidated in detail. Further understanding of the molecular basis of the potent mitogenic response initiated by bombesin is required in order to elucidate the mechanism by which the occupied receptor communicates with effector molecules in the cell. Transmembrane signalling mechanisms involving either a tyrosine kinase or a guanine nucleotide-binding regulatory protein (G protein) have been proposed. Here we summarize our experimental evidence indicating that a G protein(s) is involved in the coupling of the bombesin receptor to the generation of intracellular signals related to mitogenesis. Evidence for the role of G proteins in bombesin signal transduction pathways has been obtained by assessing the effects of guanine nucleotide analogues on both receptor-mediated responses in permeabilized cells and ligand binding in membrane preparations. We found that [125I]GRP-receptor complexes were solubilized from Swiss 3T3 cell membranes by using the detergents taurodeoxycholate or deoxycholate. Addition of guanosine 5-[γ-thio]triphosphate (GTPγS) to ligand-receptor complexes isolated by gel filtration enhanced the rate of ligand dissociation in a concentration-dependent and nucleotide-specific manner. These results demonstrate the successful solubilization of [125I]GRP-receptor complexes from Swiss 3T3 cell membranes and provide evidence for the physical association between the ligand-receptor complex and a guanine nucleotide binding protein(s).
Biogenesis of synaptic vesicles
Authors: Kelly R. B. , Bonzelius Frank , Cleves Ann , Clift-O’Grady Lois , Grote Eric , Herman Gary
Published: May 2013

The basic endosomal recycling pathway can be modified to generate transcytotic vesicles, storage vesicles and synaptic vesicles. Sorting into synaptic vesicles requires specialized sorting information not present in the transcytotic and storage vesicle proteins. Using mutagenesis we have distinguished the signals for rapid endocytosis and SV targeting in synaptobrevin. Finally, we have evidence that synaptic vesicles can be generated from an endosomal compartment in vitro.
Dysfunction of CFTR bearing the AF508 mutation
Authors: Welsh Michael J. , Denning Gerene M. , Ostedgaard Lynda S. , Anderson Matthew P.
Published: May 2013

The cystic fibrosis transmembrane conductance regulator (CFTR) is mutated in patients with cystic fibrosis (CF). The most common CF-associated mutation is deletion of phenylanine at residue 508, CFTRAF508. When expressed in heterologous cells, CFTR bearing the AF508 mutation fails to progress through the normal biosynthetic pathway and fails to traffic to the plasma membrane. As a result, CFTRAF508 is mislocalized and is not present in the apical membrane of primary cultures of airway epithelia. Consequently, the apical membrane of CF airway epithelia is Cl--impermeable, a defect that probably contributes to the pathogenesis of the disease.
Baudrillard's simulated ecology
Authors: Beever Jonathan
Published: May 2013

Jean Baudrillard, the scholar and critic of postmodernity, struggled with questions of postmodern ontology: representation of the real through the semiotic process of signification is threatened with the rise of simulacra, the simulated real. With this rise, seductive semiotic relationships between signs replace any traditional ontological representamen. This struggle has implications for environmentalism since the problems of contemporary environmental philosophy are rooted in problems with ontology. Hence the question of postmodern ecology: can the natural survive postmodern simulation? Baudrillard's communicative analysis of semiotic postmodernity can both support and extend ecosemiotic theses in response to these questions, questions that must be answered in order to explore our paradoxical understandings of the natural and confirm an understanding of environmentalism for postmodernity. In this paper I will argue for the merit of a semiotic understanding of postmodernity, develop the idea of ecology in this context, and then compare Baudrillard's approach to the contemporary development of ecosemiotics.