bluuebunny/crossref_metadata_2025 huggingface dataset:
Ash from the Eyjafjallajökull eruption (Iceland): Fragmentation processes and aerodynamic behavior
Authors: Dellino P. , Gudmundsson M. T. , Larsen G. , Mele D. , Stevenson J. A. , Thordarson T. , Zimanowski B.
Published: November 2011

The fragmentation process and aerodynamic behavior of ash from the Eyjafjallajökull eruption of 2010 are investigated by combining grain‐size, Scanning Electron Microscopy (SEM), and quantitative particle morphology. Ash samples were collected on land in Iceland at 3–55 km distance from the volcanic vent, and represent various phases of the pulsating eruption. The grain size is fine even for deposits close to the vent, suggesting that the parent particle population at fragmentation consisted of a substantial amount of fine ash. SEM investigation reveals that ash produced during the first phase of the eruption consists of juvenile glass particles showing key features of magma‐water interaction, suggesting that phreatomagmatism played a major role in the fragmentation of a vesicle‐poor magma. In the last phase of the eruption, fragmentation was purely magmatic and resulted from stress‐induced reaction of a microvesicular, fragile melt. The shape of ash, as determined by quantitative morphology analysis, is highly irregular, rendering the settling velocity quite low. This makes transportation by wind much easier than for other more regularly shaped particles of sedimentary origin. We conclude that the combination of magma's fine brittle fragmentation and irregular particle shape was the main factor in the extensive atmospheric circulation of ash from the mildly energetic Eyjafjallajökull eruption.
Dendroseismology on the central North Anatolian fault, Turkey: Documenting three centuries of surface rupture history using tree rings
Authors: Kozacı Özgür
Published: November 2011

Tree ring analysis provides a precise dating source for characterizing the timing of natural hazards. Specifically, seismogenic disturbances on trees have been successfully documented on major faults such as the San Andreas fault in California and Denali fault in Alaska. In this study, dendroseismology was employed along a 15‐km‐long stretch of the central North Anatolian fault (NAF) between Ilgaz and Tosya, Turkey where the most recent surface rupturing event was the Mw 7.6 1943 A.D. earthquake. Morphologic documentation and dendrochronologic analyses of 28Pinus sylvestristrees demonstrates the effects of proximal surface rupture and secondary earthquake deformation. Fourteen trees show similar abrupt growth suppression and accelerated recovery trends following the 1943 A.D. Tosya earthquake. The number of trees yielding similar results, the linear spatial distribution of the traumatized trees along the NAF, similarity in the trend of annual ring growth response, and synchronity of these anomalies with the 1943 A.D. earthquake provide robust evidence for the correlation of the observed anomalies and the earthquake. In addition, four trees going back to early 18th century provide evidence for the lack of another surface rupturing large magnitude earthquake along this stretch of the fault. This finding corroborates that the historical 1668 A.D. earthquake is most likely the penultimate event for the Ilgaz‐Tosya segment of the NAF.
A closed‐form conversion from spherical‐wave‐ to complex‐point‐source‐expansion
Authors: Martini E. , Maci S.
Published: November 2011

A simple closed‐form expression for a complex point source (CPS) beam expansion of an arbitrary electromagnetic field is derived. The expansion process consists of two steps: first, a particular form of the equivalence principle is applied to a sphere enclosing the real sources, and a continuous equivalent electric current distribution is obtained in terms of spherical waves (SW); then, the continuous current is extended to complex space and its SW components are properly filtered and sampled to generate the discrete set of CPS. The final result is a compact finite series representation suitable for arbitrary radiated fields, and particularly efficient when the source is highly directional and/or the observation domain is limited to a given angular sector. The robustness of the process is demonstrated by showing its connection with the singular value decomposition of the radiation operator from a complex sphere.
On the Hydrides of B, C, N, O and F
Authors: Bucknum Michael , Castro Eduardo
Published: November 2011

This paper reports a productive discussion of bonding principles in the non-metallic 2nd row hydrides. It suggests the inversion of a bonding character, potentially from hydrides of B & C, which may display unsaturation and electronic deficiency accompanied by electronic delocalization in 1D or 2D or 3D. Contrasted with the opposite possibility, within the finite number of hydrides of N, O and F, that display apparently extensive H-bonding and subsequently proton delocalization in 1D and 2D (in HF & ice polymorphs, respectively), and now potentially in 3D in a corresponding hydride of N called Rice's blue material, or perhaps polyimidogen. Where polyimidogen is a crystalline NH lattice that is a polymorph of the ammonium azide structure-type thus.
Participatory Forest Management: The Role of Farmers Associations in the Rehabilitation of the Gum Arabic Belt
Authors: Ramly F.M.A.
Published: November 2011

Sudan exhibits a series of variations in soils, climatic conditions and hence ecological zones ranging from hot dry desert in the north to the moist tropical climate in the South. Acacia senegal L (Willd.) is the most important tree species in Sudan with a wide range of uses, it produces gum arabic, stabilises soils, is used as fodder, fertilises soils by fixing atmospheric nitrogen, and is used as fire wood. Gum arabic is the natural gummy exudate obtained by tapping the branches of A. senegal trees and its closely related species.
Genetic Characterisation of Kenyan Acacia Senegal for Possible Improvement in Gum Arabic Quality and Production
Authors: Dangasuk O.G. , Chiveu C.J. , Omondi S.F.
Published: November 2011

Acacia senegal (L.) Willd is an arid and semi arid lands (ASALs), leguminous multipurpose tree species belonging to the subfamily Mimosoideae, family Fabaceae and subgenus Aculeiferum.
Determination of Optimum Tapping Date for Gum Arabic Production in the Nuba Mountain Area, South Kordofan State, Sudan
Authors: Omer I.M.A , Fadl K.E.M. , Masuad M.M.
Published: November 2011

Acacia senegal provides building poles; hedging material and fuel wood for local use, and its roots are used for lining wells and thatching baskets. Acacia senegal yields 95% of the gum arabic exported from the Sudan, the remaining (5%) coming from Acacia seyal var. seyal (Talha in arabic).
Structural Changes Following Industrial Processing of Acacia Gums
Authors: Al-Assaf S. , Andres-Brull M. , Cirre J. , Phillips G.O.
Published: November 2011

This paper reviews the various processing operations starting from gum collection to the commercial end product. Following gum collection the first important step is the drying process. Drying in direct sunlight should be avoided and gradual drying in the shade is recommended. Fresh gum is often called “green gum” which is characterised by high moisture content and less arabinogalactan protein (AGP) fraction compared to a gum which has been stored over a period of time. Subsequent storage conditions can greatly influence the gum quality. The next steps are the kibbling and milling operations. The temperature rise during this process should be controlled to avoid aggregation of the proteinaceous material. This can also affect the quality, since the molecular weight increases as a function of the heat generated. The next step is the dissolution process, when the gum can be modified by the temperature and energy applied to the aqueous solution as a result of foaming. Finally spray-drying operation can result in significant changes to the gum. A 10 to 20% increase in the molecular weight can be caused by this process, but can be considerably higher depending on the way the process is conducted. The dissolution and subsequent stages, particularly the pasteurisation conditions and residence time in the spray-drying tower can contribute to these molecular changes. The current practice employed during spray-drying results in the aggregation of the proteinaceous component and reduces its hydrophobic character due to unfolding of the protein. Consequently, the reduction of the hydrophobic character greatly affects the functionality and the ability of the proteinaceous components to adsorb onto an oil droplet. The GPC-MALLS technique and direct emulsification measurements are used to identify the effect of the various processing conditions outlined above. Significant too is the variation in soil type, rainfall and other environmental factors, which are responsible for the variation in gum quality as for other crops. To address this variation we propose a practical traceability system to identify the origin of the gum and subsequent treatment.
The Interaction of Gum Arabic with Water
Authors: Hatakeyama H. , Inui Y. , Hatakeyama T. , Phillips G.O.
Published: November 2011

The chemical structure of gum Arabic (GA) is known to have complex multifractions consisting of polysaccharide branches and protein-polysaccharide complexes. X-ray and neutron scattering revealed that GA molecules in aqueous media form spherical aggregates. Atomic force microscopy (AFM) observations indicated various kinds of structures; extended, globular or their mixtures depending on sample preparation conditions.
Gum Arabic and its Anti-obese Effect
Authors: Ushida K.
Published: November 2011

Gum arabic (Acacia senegal) works as a dietary fibre that helps reduce body fat deposition. Gum arabic may have several anti-obesity effects as a dietary supplement. The lowered caloric density of the diet is the most probable mechanism involved, but our model experiments suggest that other more complicated mechanisms may be involved. Lower absorption of glucose and fat is a probable mechanism; however, this mechanism was denied in previous studies. The enhancement of fat utilisation in adipose tissues has been suggested by our recent experiments using a real-time PCR array approach. In this mechanism, the enhancement of adrenergenic stimulation in adipose tissue is important. A lowered bacterial LPS burden may also be involved.
Gum Arabic: A Reducing Agent of Uric Acid and a Supportive Treatment of Gout
Authors: Osman M.E. , Abu Zeid I.M. , Adam F.A.
Published: November 2011

Gum arabic (GA) from Acacia senegal var. senegal was orally administered to patients suffering from gout. Out of fifty randomly selected patients, twenty-five patients were given a GA dose of 50 g/day for 120 days, and the remaining twenty-five patients represented the control group. Blood samples were collected from all patients on the first day of administering GA, and once every two weeks. Uric acid, urea, creatinine, haemoglobin (Hb), packed cell volume (PCV) and erythrocyte sedimentation rate (ESR), were determined using standard methods. After a 60 day depletion period, the same parameters were determined using doses of 75 and 25 g/day of GA. The results indicate that GA consumption reduces average serum uric acid levels in both male and female gout patients in a dose dependent manner, higher doses (50 and 75 g/day) causing uric acid levels to fall below normal levels. Urea and creatinine levels, which were initially within the normal range, also decreased significantly in a GA dose dependent manner. Hb and PCV levels, which were initially decreased (compared to the control group), increased significantly in a GA dose dependent manner back towards normal (control group) levels, and at the highest GA dose (75 g/day) increased beyond normal levels. ESR levels, which were initially elevated (compared to the control group), decreased significantly in a GA dose dependent manner back towards normal (control group) levels, and at the higher GA doses (50 and 75 g/day) decreased below normal levels.
Arabic Gum in Oenology
Authors: Teissedre P.L.
Published: November 2011

Gum arabic is an exudate obtained from Acaia senegal and Acacia seyal. In its natural state, it appears as round nodules, almost transparent, amber in colour. Saharan gum arabic has a long history and is harvested in Mauritania, Senegal, Mali, Burkina Faso, Niger, Nigeria, Chad, Cameroon, Sudan, Eritrea, Somalia, Ethiopia and Kenya. Traditionally harvested by semi-nomadic desert pastoralists in the course of their season (harvesting usually begins in July), and exported at the start of the dry season (November). Gum arabic exports are (2008) estimated at 60,000 tonnes, having recovered from 1987-1989 and 2003-2005 crises caused by the destruction of trees by desert locust.
Effect of Gum Arabic and Total Solids Content on Non-volatile and Volatile Compound Retention in Microcapsules
Authors: Penroj P. , Samuhasaneetoo S.
Published: November 2011

Encapsulation is widely used to stabilise sensitive ingredients, or control their delivery in a diverse range of applications, including foods and drinks, pharmaceuticals, cosmetics, household products, and in industrial applications. There are numerous technologies available for the production of microcapsules, in which the active ingredient is either coated with, or embedded in, a second material. The second material is usually a polymer and designed to isolate the active until its release is triggered by an external stimulus. Some typical encapsulation agents are polysaccharide gums (gum arabic, agar, sodium alginate, carrageenan etc), other carbohydrates (starch, dextran, sucrose, corn syrup, etc), and proteins (gluten, casein, gelatin, albumin, etc.).
Effect of Acacia Senegal (L.) Willd on Growth and Yield of Groundnut, Sesame and Roselle in an Agroforestry System in North Kordofan, Sudan
Authors: Fadl K.E.M. , El Sheikh S.E.
Published: November 2011

Two field trials were conducted under rain fed conditions at El-Obeid Research Farm and Eldemokeya Forest Reserve, North Kordofan State, Sudan during the growing seasons 2004/05 and 2005\06. The objective was to investigate the effect of Acacia senegal on the performance and yield of groundnut (Arachis hypogea), sesame (Sesamum indicum) and roselle (Hibiscus sabdariffa) in an agroforestry system. The two trials consisted of seven treatments: three represented the intercropping of groundnut, sesame and roselle with A. senegal, three without trees, and one represented A. senegal alone. Data was recorded on soil physical and chemical properties, soil moisture content, crops fresh weight (kg/ha), dry weight (kg/ha), gum yield (g/picking) and crop yield (kg/ha). The trees at El-Obeid yielded no gum, whereas those at Eldemokeya were 15 years old and were tapped as part of the total harvest in the agroforestry plots. Land Equivalent Ratios (LER) and simple financial analyses of gross surpluses were used to evaluate productivity of the different treatments.

Fresh weight of groundnut, sesame and roselle was significantly different (p < .0.05) at both sites. Higher fresh weights were found under the intercropping system than the sole cropping system. This could be attributed to a shading effect that limits fruit production of the field crops more than vegetative growth. Dry weights were significantly greater for sesame and roselle in both sites, whilst that of groundnuts was not significantly different. In both sites intercropping reduced the yield of sesame by 6% and 11% in the first season and 37% and 39% in the second season. The reduction in roselle yield was 19% and 28% in the first season and 15% and 8% in the second season. Yield reduction in groundnut was 35% and 17% in the first season and 35% and 11% in the second season. The combined analysis indicated that intercropping reduced groundnut yield by 26%, sesame by 21% and roselle by 20%.

All the treatments gave land equivalent ratio (LER) of more than one - indicating the superiority of growing the field crops in intercropping over the sole cropping systems. The highest LER of (1.71) was obtained when roselle was intercropped with A. senegal, whilst the lowest LER (1.48) was obtained when groundnuts were intercropped with A. senegal. All the treatments gave positive net revenues, the highest being for intercropped roselle (438 SDG\ha). The intercropping of sesame gave the second highest net revenue (387 SDG\ha), whilst the sole roselle gave the lowest net revenue (97 SDG\ha).
Biological Interactions with Surface Charge in Biomaterials
Authors:   Royal Society of Chemistry,   Royal Society of Chemistry
Published: November 2011

When a biomaterial is placed inside the body, a biological response is triggered almost instantaneously. With devices that need to remain in the body for long periods, such interactions can cause encrustation, plaque formation and aseptic loosening on the surface. These problems contribute to the patient's trauma and increase the risk of death. Electrical properties, such as local electrostatic charge distribution, play a significant role in defining biological interactions, although this is often masked by other factors. This book describes the fundamental principles of this phenomenon before providing a more detailed scientific background. It covers the development of the relevant technologies and their applications in therapeutic devices such as MRSA-resistant fabrics, cardiovascular and urological stents, orthopaedic implants, and grafts. Academic and graduate students interested in producing a selective biological response at the surface of a given biomaterial will find the detailed coverage of interactions at the nanometre scale useful. Practitioners will also benefit from guidance on how to pre-screen many inappropriate designs of biomedical devices long before any expensive, animal or potentially risky clinical trials. Enhanced by the use of case studies, the book is divided in to four topical sections. The final section is dedicated to the application of related topics making the book unique in its pragmatic approach to combining high end interdisciplinary scientific knowledge with commercially viable new technologies. Contributing to the newly emerging discipline of 'nanomedicine', the book is written not only by experts from each relevant specialty but also by practitioners such as clinicians and device engineers from industry.
Photocatalytic Effects in Doped and Undoped Titania
Authors: Kopaczyńska M. , Vargová M. , Wysocka-Król K. , Plesch G. , Podbielska H.
Published: November 2011

Improving the spectral sensitivity of photocatalysts may significantly enhance photoprocesses by distinctly absorbing more light. The design of more selective photocatalysts that can be activated by visible light and can be applied in medical diagnosis or therapy (in cancer treatment, implantology or as an antibacterial material) or novel photocatalysts for the production of energy resources (from biomass or from water splitting) are among the major goals of application for doped and undoped titania photocatalysts in biological and chemical applications. Here, we discuss surface charge generation and photocatalysis in nano-titania and methods of obtaining a shift to a higher wavelength for this photocatalytic transition. With some examples, we also show how photocatalysis can be probed.
Surface Charge Measurements on Biomaterials in Dry and Wet Conditions
Authors: Gregor M. , Plecenik T. , Plecenik A. , Wolf-Brandstetter C. , Scharnweber D. , Tofail S. A. M.
Published: November 2011

The most commonly used charge measurement methods in dry and wet condition are discussed in this Chapter. A number of methods [thermally stimulated depolarization current (TSDC), induction probe, field mill, electrostatic force microscopy (EFM) and Kelvin probe force microscopy (KPFM)] for electrostatic charge measurement in dry conditions have been reviewed. The TSDC method is capable of measuring the integral charge at the surface, as well as in the volume of the sample, but the charge is destroyed by the measurement. On the other hand, induction techniques are sensitive only to the surface charge, but they are usually non-contact and non-destructive. In particular, scanning probe microscopy (SPM) techniques allow the measurement of surface charge with high lateral (tens of nanometres) and potential (∼mV) resolution. In wet conditions, the streaming potential technique is most commonly used for surface potential measurements, although KPFM can also be employed in certain cases.
Non-linear Characterizations of Surface Charge and Interfacial Morphology
Authors: Lang S. B. , Stanciu G. A. , Stanciu S. G.
Published: November 2011

This Chapter discusses a special technique for the measurement of surface and subsurface charge in electrically modified biomaterials. In addition, it also describesthe laser scanning microscopy technique used in surface and interfacial characterisation of biomaterials and biological materials. Corona poling/charging is a very useful method for introducing polarization into polar materials and space charge in non-polar ones. The apparatus required is relatively inexpensive and a large number of parameters can be varied. The laser intensity modulation method (LIMM) is an excellent technique for analysis of the polarization/space charge deposited in regions near the surface of the materials by corona charging. Preliminary experiments were conducted to show the effects of corona polarity, charging time and temperature, and charge loss by storage in different media. Laser scanning microscopy based on second harmonic (SH) imaging represents a very useful tool for investigating the surface structure and the interfacial properties of the biological samples. The combined strong scattering and absorption of ultraviolet and visible light in the case of confocal microscopy lead to a rapid loss of both intensity and contrast when the penetration depth in the tissues is higher than a few tens of microns into tissue. Unlike in confocal microscopy, in the case of the SH imaging the scanning light is able to penetrate much deeper inside the sample's volume.
Antibody Immobilization on Solid Surfaces: Methods and Applications
Authors: Hu X. , O’Connor I. B. , Wall J. G.
Published: November 2011

The correct immobilization of the antibody component is one of the most critical steps in the development of immunoassays, immunosensors and immunochromatography matrices. Advances in hybridoma technology and protein engineering have allowed traditional limitations of polyreactivity of antibody preparations, poor device stability and random orientation of binding pockets to be largely overcome, resulting in stable, sensitive, highly specific and enormously diverse immunoplatforms with applications in diagnostics, environmental monitoring, and food and public safety. In this Chapter we introduce antibody structure and antibody-derived fragments, describe the most common methods of their immobilization and discuss ‘traditional’ applications of immobilized antibodies such as enzyme immunoassays and immunoaffinity chromatography, as well as exciting emerging uses in immunosensors, microarrays and nanomedicine.
Interactions of Bone-forming Cells with Electrostatic Charge at Biomaterials’ Surfaces
Authors: Hempel U. , Wolf-Brandstetter C. , Scharnweber D.
Published: November 2011

In vitro cell culture experiments that determine cell adhesion, proliferation and differentiation are valuable tools for evaluating the biocompatibility of biomaterial modifications with charged surfaces. This Chapter will give a short overview of the basic principles of cell adhesion, then discuss some of the practical aspects of determining the proliferation of adherent cells and review cell differentiation with a focus on the osteogenic path. Finally, the impact of charged surfaces on the described cell behaviour is discussed.
Interactions of Biofilm-forming Bacteria with Abiotic Surfaces
Authors: Robin S. , Soulimane T. , Lavelle S.
Published: November 2011

Biofilms are complex dynamic systems that have been in existence for more than 3 billion years and constitute an integral component of the prokaryotic lifestyle. The biofilm offers a protected mode of growth that not only allows microorganisms to colonize natural environments, but alsoliving hosts. Bacterial adhesion is the first and crucial step in surfaces colonization and biofilm formation,and it is mediated by an ensemble of physical and molecular interactions. Although our knowledge about this process is already substantial, existing thermodynamic models are often insufficient to accurately predict the behaviour of cells towards a surface. At present, it seems that a major cause of the failure of those models lies in the heterogeneity of both cells and abiotic surfaces. Very recent studies on electrostatic interactions clearly demonstrate that bacterial adhesion could be predicted using existing thermodynamic models only if surface charge heterogeneity at a microscale level is considered. Furthermore, the available models reduce microbe/abiotic surface arrangements to static systems, while the dynamic nature of microbial cells has to be accounted for as they can actively modulate their surface properties to adhere. Therefore, the development of efficient and versatile anti-biofilm treatments, in particular for medical applications, after decades of research still poses an extreme challenge.
Endothelial Cells and Smooth Muscle Cells: Interactions at Biomaterials’ Surfaces
Authors: Wawrzyńska M. , Sobieszczańska B. , BiaŁy D. , Arkowski J.
Published: November 2011

Endothelial cells and smooth muscle cells (SMCs) are the key elements in the pathogenesis and treatment of vascular disease. We are beginning to understand their intricate interactions. Dysfunction of arterial endothelium is the first stage of atherosclerosis, but it is the migration and proliferation of other cells (SMCs included) that forms the plaque. Our current understanding of in-stent restenosis is based on the concept of vessel wall injury, de-endothelization and the exposure of SMCs from tunica media. Endothelialization of the implant ensures healing of the intervention site. Migration of SMCs into the vessel lumen, their proliferation and secretion of the extracellular matrix are the key elements of restenosis. It is the delicate play between those two types of cells that needs to be understood and ideally also regulated in order to make the effects of intravascular interventions long-lasting.
The Reduction of Restenosis in Cardiovascular Stents
Authors: Arkowski J. , Wawrzyńska M. , BiaŁy D. , Sobieszczańska B. , Mazurek W.
Published: November 2011

This Chapter presents an overview of the current and emerging strategies and techniques for the reduction of restenosis in cardiovascular stents. The Chapter discusses the importance of intravascular stents and the general technology involved in stents from a clinician's perspective. Stent structure engineering and the issues pertaining to biodegradable stents are discussed along with the novel approaches for stent surface modification.
Manipulation of Interfaces on Vector Materials
Authors: Horiuchi, N. , Nakamura M. , Nagai A. , Yamashita K.
Published: November 2011

We define a vector material as one that can manipulate its surrounding using force irradiating locally and continuously from the material itself. The effect produced by a vector material has unparalleled importance under the circumstance of the limited use of external forces such as in vivo. We have found that hydroxyapatite (HAp) ceramics become electrets via the electric polarization procedure, and the electrets have vector effects, which can manipulate their surrounding constituents. The polarized HAp electrets accelerate and decelerate crystal growth rate in simulated body fluid (SBF), and control the proliferation of microorganism. In addition to our examples, some types of vector materials are found and employed in biomedical applications: bioactive glass and radioactive materials. Bioactive glass solves in aqueous medium, thus, the solubility work on the environment. Radioactive materials irradiate β-rays to and affect cancer cells in the vicinity of the materials. This Chapter also presents the concept of vector effects and reviews the examples of vector materials.
Re-examination of the dimerization state of leucine-rich repeat kinase 2: predominance of the monomeric form
Authors: Ito Genta , Iwatsubo Takeshi
Published: November 2011

Mutations in the LRRK2 (leucine-rich repeat kinase 2) gene have been identified in PARK8, a major form of autosomal-dominantly inherited familial Parkinson's disease, although the biochemical properties of LRRK2 are not fully understood. It has been proposed that LRRK2 predominantly exists as a homodimer on the basis of the observation that LRRK2, with a theoretical molecular mass of 280 kDa, migrates at 600 kDa (p600 LRRK2) on native polyacrylamide gels. In the present study, we biochemically re-examined the nature of p600 LRRK2 and found that p600 LRRK2 was fractionated with a single peak at ~272 kDa by ultracentrifugation on a glycerol gradient. In addition, p600 LRRK2 behaved similarly to monomeric proteins upon two-dimensional electrophoretic separation. These results suggested a monomeric composition of p600 LRRK2 within cells. The p600 LRRK2 exhibited kinase activity as well as GTP-binding activity, and forced dimerization of LRRK2 neither upregulated its kinase activity nor altered its subcellular localization. Collectively, we conclude that the monomer form of LRRK2 is predominant within cells, and that dimerization is dispensable for its enzymatic activity.
Broncholithiasis, Lithoptysis und broncho-ösophageale Fistel
Authors: Westhoff M. , Litterst P. , Al-Shahrabani F.
Published: November 2011

Broncho-ösophageale Fisteln bei Broncholithiasis sind extrem selten. Eine vorausgehende Lithoptysis wird nur vereinzelt beschrieben. Berichtet wird über einen 68-jährigen Patienten, der über eine mehr als 3 Jahre bestehende Hustensymptomatik klagte. 5 Monate vor der stationären Aufnahme trat eine Hämoptyse mit begleitendem Abhusten von mehreren gräulichen, bis zu 5 mm im Durchmesser großen Steinen auf. Bei der Bronchoskopie zeigte sich eine kleine Exkavation an der medialen Wand des linken Hauptbronchus. Im Vergleich zu einem vorausgegangenen CT konnte auf einem aktuellen CT eine kleine Fistel zwischen Ösophagus und linkem Hauptbronchus sowie eine nicht mehr vorhandene Kalzifikation in diesem Bereich nachgewiesen werden. Der Patient wurde linksseitig thorakomiert. Es erfolgte die Exzision der Fistel, Übernähung des Ösophagus und Interposition eines M. latissimus dorsi Lappens. Der Nachweis einer Broncholithwanderung mittels CT vor und nach der Lithoptyse, die Ausbildung einer linksseitigen Fistel und ihre Darstellung im CT sowie bei der Bronchoskopie wurden in dieser Kombination bislang nicht in der Literatur berichtet.
Relationship between the timing of prostaglandin-induced luteolysis and effects on the conceptus during early pregnancy in mares
Authors: Betteridge Keith J. , Waelchli Rudolf O. , Christie Heather L. , Raeside James I. , Quinn Bette A. , Hayes M. Anthony
Published: November 2011

To advance the understanding of early pregnancy and pregnancy failure in horses, this study determined how luteolysis induced by cloprostenol (an analogue of prostaglandin F2α) affects conceptus development. Mares were injected on Days 12, 14, 16 or 18 of pregnancy with either cloprostenol (treatment groups, total n = 83 pregnancies) or saline (controls, n = 81), and growth of the conceptuses was monitored and compared by daily ultrasonography until they were collected transcervically on Days 15–22, 1–4 days after the injections. The comparisons were extended in the recovered conceptuses by counting somites, measuring the volume and osmolality of yolk-sac fluid and its concentrations of proteins, estrone sulfate and progesterone, and by assessing the morphology of the capsule and vascular system. When luteolysis was initiated on or before Day 16, most pregnancies survived until the time of collection and the conceptuses in respective treated and control groups on Days 15–20 were very similar except for some effects of treatment on the capsule and vascular development. In contrast, after luteolysis was initiated on Day 18, abortion often ensued within 3 days and most conceptuses collected had degenerated, therein constituting a predictable system in which to study the pathogenesis of a particular cause of pregnancy failure.
The importance of piled wood debris on the distribution of bird-dispersed plants in burned and logged Mediterranean pine forests
Authors: Rost J. , Bas J. M. , Pons P.
Published: November 2011

Plant dispersal and colonisation are important processes in vegetation recovery after fire and, for several species, depend on the presence of frugivorous avian seed dispersers. In burned and salvage-logged Mediterranean pine forests, the occurrence of disperser birds is enhanced by the presence of wood debris piles built as erosion barriers, which become seed dispersal foci. We hypothesised that the distribution of bird-dispersed plants after fire could be determined by the presence of wood piles. We analysed the differences in species richness and overall cover of bird-dispersed plants, as well as the cover of the most common species, within piles and outside them. We also tested if micro-environmental conditions (slope orientation and pile size) might influence plant occurrence. We found more species and overall cover within piles, when located on southern and south-eastern slopes, than outside them. Moreover, taller piles showed higher values of bird-dispersed plant cover and richness. Therefore, wood piles may provide the necessary conditions for bird-dispersed plant recruitment in dry burned areas. To our knowledge, this is the first reported man-made structure that clearly benefits the recovery of bird-dispersed plants in burned areas, and suggests that piles may be a useful restoration measure when logging Mediterranean burned forests.
Rapid degradation of cyclooxygenase-1 and hematopoietic prostaglandin D synthase through ubiquitin–proteasome system in response to intracellular calcium level
Authors: Yazaki Misato , Kashiwagi Kaori , Aritake Kosuke , Urade Yoshihiro , Fujimori Ko
Published: November 2011

Cyclooxygenase (COX)-1 and hematopoietic prostaglandin (PG) D synthase (H-PGDS) proteins, which are both involved in the arachidonate cascade, were stable in human megakaryocytic MEG-01 cells. In contrast, once the intracellular calcium level was increased by treatment with a calcium ionophore, both protein levels rapidly decreased with a half-life of less than 30 and 120 min for COX-1 and H-PGDS, respectively. In the presence of a proteasome inhibitor, COX-1 and H-PGDS proteins accumulated within 10 and 30 min, respectively, and concurrently appeared as the high-molecular-mass ubiquitinated proteins within 30 and 60 min, respectively, after an increase in the intracellular calcium level. The ubiquitination of these proteins was also observed when ADP, instead of a calcium ionophore, was used as an inducer to elevate the intracellular calcium level. When the entry of calcium ion into the cells was inhibited by ethylene glycol tetraacetic acid (EGTA), the ubiquitination of COX-1 and H-PGDS was clearly suppressed; and the addition of CaCl2to the medium cleared the EGTA-mediated suppression of the ubiquitination. These results indicate that COX-1 and H-PGDS were rapidly ubiquitinated and degraded through the ubiquitin–proteasome system in response to the elevation of the intracellular calcium level.
A Statistical Model for Party-Systems Analysis
Authors: Rozenas Arturas , Alvarez R. Michael
Published: November 2011

Empirical researchers studying party systems often struggle with the question of how to count parties. Indexes of party system fragmentation used to address this problem (e.g., the effective number of parties) have a fundamental shortcoming: since the same index value may represent very different party systems, they are impossible to interpret and may lead to erroneous inference. We offer a novel approach to this problem: instead of focusing on index measures, we develop a model that predicts theentire distributionof party vote-shares and, thus, does not require any index measure. First, a model of party counts predicts the number of parties. Second, a set of multivariatetmodels predicts party vote-shares. Compared to the standard index-based approach, our approach helps to avoid inferential errors and, in addition, yields a much richer set of insights into the variation of party systems. For illustration, we apply the model on two data sets. Our analyses call into question the conclusions one would arrive at by the index-based approach. Software is provided to implement the proposed model.
The aerodynamics of jumping rope
Authors: Aristoff Jeffrey M. , Stone Howard A.
Published: November 2011

We consider the influence of aerodynamic forces on the shape of a whirling filament that is held at both ends, i.e. a jump rope. At high Reynolds numbers, the rope curls out of the plane and towards the axis of rotation—a feature we demonstrate via experiment. We derive a pair of coupled nonlinear differential equations that characterize the steady-state shape of the rope, and the resulting eigenvalue problem is solved numerically. The solution depends on two dimensionless groups: the ratio between the length of the rope and the distance between its ends, and the relative magnitude of the aerodynamic to centrifugal forces. As the latter ratio is progressively increased, the tension in the rope and the out-of-plane deflection increases, until eventually the rope reaches a limiting shape. Finally, we show that the airflow-induced shape change leads to a relative reduction in drag and has implications for successful skipping.
The role of neutralizing antibodies in hepatitis C virus infection
Authors: Edwards Victoria C. , Tarr Alexander W. , Urbanowicz Richard A. , Ball Jonathan K.
Published: November 2011

Hepatitis C virus (HCV) is a blood-borne virus estimated to infect around 170 million people worldwide and is, therefore, a major disease burden. In some individuals the virus is spontaneously cleared during the acute phase of infection, whilst in others a persistent infection ensues. Of those persistently infected, severe liver diseases such as cirrhosis and primary liver cancer may develop, although many individuals remain asymptomatic. A range of factors shape the course of HCV infection, not least host genetic polymorphisms and host immunity. A number of studies have shown that neutralizing antibodies (nAb) arise during HCV infection, but that these antibodies differ in their breadth and mechanism of neutralization. Recent studies, using both mAbs and polyclonal sera, have provided an insight into neutralizing determinants and the likely protective role of antibodies during infection. This understanding has helped to shape our knowledge of the overall structure of the HCV envelope glycoproteins – the natural target for nAb. Most nAb identified to date target receptor-binding sites within the envelope glycoprotein E2. However, there is some evidence that other viral epitopes may be targets for antibody neutralization, suggesting the need to broaden the search for neutralization epitopes beyond E2. This review provides a comprehensive overview of our current understanding of the role played by nAb in HCV infection and disease outcome and explores the limitations in the study systems currently used. In addition, we briefly discuss the potential therapeutic benefits of nAb and efforts to develop nAb-based therapies.
Immunogenic compositions assembled from tobacco mosaic virus-generated spherical particle platforms and foreign antigens
Authors: Karpova Olga , Nikitin Nikolai , Chirkov Sergey , Trifonova Ekaterina , Sheveleva Anna , Lazareva Ekaterina , Atabekov Joseph
Published: November 2011

We reported recently that RNA-free spherical particles (SPs) generated by thermal remodelling of tobacco mosaic virus (TMV) are capable of binding GFP to their surface. Here, we show that SPs represent a universal particle platform that can form compositions by binding a diversity of various foreign proteins/epitopes of viral and non-viral origin to their surface. Numerous molecules of a foreign protein linked to the SP surface were revealed by immunogold electron microscopy. Several SP-based compositions were obtained containing one of the following foreign antigens: antigenic determinant A of rubella virus E1 glycoprotein; a recombinant protein containing the M2e epitope of influenza virus A protein M2; a recombinant antigen consisting of three epitopes of influenza virus A haemagglutinin; potato virus X (PVX) coat protein (CP); BSA; and PVX CP fused with the epitope of plum pox virus CP. The ‘mixed’ compositions could be also assembled by binding two different foreign antigens to each of the SPs. Immunogenicity of foreign antigens adsorbed or linked covalently to SPs in the SP-based compositions was examined. The antigenic specificity of foreign antigens was retained, whereas their immunogenicity increased significantly. It was inferred that SPs exhibit immunopotentiating activity, in particular in the form of compositions comprising SP and foreign antigen linked covalently to their surface by formaldehyde.
Activation of the beta interferon promoter by paramyxoviruses in the absence of virus protein synthesis
Authors: Killip M. J. , Young D. F. , Precious B. L. , Goodbourn S. , Randall R. E.
Published: November 2011

Conflicting reports exist regarding the requirement for virus replication in interferon (IFN) induction by paramyxoviruses. Our previous work has demonstrated that pathogen-associated molecular patterns capable of activating the IFN-induction cascade are not normally generated during virus replication, but are associated instead with the presence of defective interfering (DI) viruses. We demonstrate here that DIs of paramyxoviruses, including parainfluenza virus 5, mumps virus and Sendai virus, can activate the IFN-induction cascade and the IFN-β promoter in the absence of virus protein synthesis. As virus protein synthesis is an absolute requirement for paramyxovirus genome replication, our results indicate that these DI viruses do not require replication to activate the IFN-induction cascade.
Internet Addiction and Antisocial Internet Behavior of Adolescents
Authors: Ma Hing Keung
Published: November 2011

Internet addiction and the moral implication of antisocial Internet behavior will be investigated in this paper. More and more people use the Internet in their daily life. Unfortunately the percentage of people who use the internet excessively also increases. The concept of Internet addiction or pathological use of Internet is discussed in detail, and the characteristics of Internet addicts are also delineated. The social (especially the antisocial) use of Internet is discussed. It is argued that the behavior of Internet use is similar to daily life social behavior. In other words, Internet behavior is a kind of social behavior. Kohlberg's theory of moral development is employed to delineate the moral reasoning of the antisocial Internet behavior. The following behaviors are regarded as antisocial Internet behavior: (1) the use of Internet to carry out illegal activities such as selling faked products or offensive pornographic materials, (2) the use of Internet to bully others (i.e., cyberbullying) such as distributing libelous statements against a certain person, (3) the use of Internet to cheat others, and (4) the use of Internet to do illegal gambling. The characteristics of the moral stages that are associated with these antisocial Internet behaviors are investigated in detail.
Stem Cell Heterogeneity of Mononucleated Cells from Murine Peripheral Blood: Molecular Analysis
Authors: Yazid Muhammad Dain , Zainal Ariffin Shahrul Hisham , Senafi Sahidan , Zainal Ariffin Zaidah , Megat Abdul Wahab Rohaya
Published: November 2011

The main purpose of this paper was to determine the heterogeneity of primary isolated mononucleated cells that originated from the peripheral blood system by observing molecular markers. The isolated cells were cultured in complete medium for 4 to 7 days prior to the separation of different cell types, that is, adherent and suspension. Following a total culture time of 14 days, adherent cells activated theCd105gene while suspension cells activated theSca-1gene. Both progenitor markers,Cbfa-1andOstf-1, were inactivated in both suspension and adherent cells after 14-day culture compared to cells cultured 3 days in designated differentiation medium. In conclusion, molecular analyses showed that primary mononucleated cells are heterogeneous, consisting of hematopoietic stem cells (suspension) and mesenchymal stem cells (adherent) while both cells contained no progenitor cells.
Some Insights into Analytical Bias Involved in the Application of Grab Sampling for Volatile Organic Compounds: A Case Study against Used Tedlar Bags
Authors: Ghosh Samik , Kim Ki-Hyun , Sohn Jong Ryeul
Published: November 2011

In this study, we have examined the patterns of VOCs released from used Tedlar bags that were once used for the collection under strong source activities. In this way, we attempted to account for the possible bias associated with the repetitive use of Tedlar bags. To this end, we selected the bags that were never heated. All of these target bags were used in ambient temperature (typically at or below 30°C). These bags were also dealt carefully to avoid any mechanical abrasion. This study will provide the essential information regarding the interaction between VOCs and Tedlar bag materials as a potential source of bias in bag sampling approaches.
Construction of a Teaching Package on Promoting Prosocial Internet Use and Preventing Antisocial Internet Use
Authors: Ma Hing Keung , Chu Miranda K. Y. , Chan Winnie W. Y.
Published: November 2011

In the construction of the teaching package on the Internet use, two major moral characters, respect and responsibility, form the core theoretical basis. The respect character consists of respect for others and self-respect while the responsibility character contains social, civil, and global responsibility. There are a total of nine units on the Internet use in the junior secondary curriculum. There are two units in Secondary One curriculum: the first unit deals with cheating behavior and privacy issues concerning the Internet, and the second one discusses the effect of excessive use of the Internet on life and study. In Secondary Two curriculum, we discuss the following social phenomena on the Internet with students: online shopping, pornographic materials on internet, and infringement of a copyright. Finally, we have designed four units on the Internet use in Secondary Three curriculum which focuses more on the relationship between the Internet use and our health. We try to answer the question on how we can use the Internet healthily and also the possibility on how it may hurt us. Similar to the second unit in Secondary One curriculum, we have designed three more units on discussing the effects of excessive use of the Internet with students. We would like to alert students that ineffective use of the Internet will hurt us mentally and physically. For illustrative purposes, two units in the Secondary One and Two curriculums are outlined in this paper.