bluuebunny/crossref_metadata_2025 huggingface dataset:
Incompetence of internal jugular vein valve in patients with transient global amnesia
Authors: Jovanovic Zagorka , Vujisic-Tesic Bosiljka , Pavlovic Aleksandra , Zidverc-Trajkovic Jasna , Mijajlovic Milija , Boricic-Kostic Marija , Cvitan Edita , Radojicic Aleksandra , Tomic Gordana , Sundic Ana , Sternic-Covickovic Nadezda
Published: January 2011

Background/Aim. Transient global amnesia (TGA) could be related to acute
ischemic disturbances in mesial parts of temporal lobes, which are important
for memory. Incompetence of internal jugular vein (IJV) valve with venous
congestion causes venous microthrombosis of hippocampus. The aim of this
study was to investigate the frequency of IJV valve incompetence, as well as
other hemodynamic and structural properties of cerebral circulation in TGA
patients. Methods. IJV valve competence was investigated in 40 TGA patients
and 30 persons of the control group (matched by age and sex), as well as
detection of microembolic signals and detection of right to left
cardiopulmonal shunt, cerebral vasomotor reactivity and echocardiography by
color triplex ultrasonography and transcranial doppler. Results. A
significant difference in frequency of IJV valve incompetence was found
between the TGA patients and the control persons (55% TGA vs 30% controls; p
< 0.001). We did not find a significant structural (plaques frequency) or
hemodynamic (flow velocity, pulsatility index) differences on arteries of the
neck and cerebral arteries between the TGA patients and the controls, except
for the increased pulsatility index on the basilar artery (40% TGA vs 16.6%
controls; p < 0.01) and decreased vasomotor reactivity in TGA patients (50%
TGA vs 26.6% controls; p < 0.001). Microembolic signals were detected very
rarely (17.5% TGA patients vs 13.3% controls; p > 0.05), as well as right to
left cardiopulmonal shunt (15% TGA vs 16.6% controls; p > 0.05), indicating
that embolism was not important for pathogenesis of TGA. Transesophageal
echocardiography confirmed it, because only one TGA patient had a potent
foramen ovale. Conclusion. We found a significantly increased frequency of
IJV incompetence in the TGA patients, which confirmed the role of vein
drainage disturbances in pathogenesis of TGA.
Pathogen inactivation in fresh frozen plasma using riboflavin and ultraviolet light: Effects on plasma proteins and coagulation factor VIII
Authors: Stanojkovic Zoran , Antic Ana
Published: January 2011

Background/Aim. Riboflavin (vitamin B2) activated by ultraviolet (UV) light,
produces active oxygen which damages cell membrane and prevents replication
of the carrier of diseases (viruses, bacteria, protozoa) in all blood
products. The aim of this study was to establish the influence of the process
of photo inactivation in pathogens using riboflavin and UV rays on the
concentration of coagulation factor VIII:C (FVIII:C) and proteins in plasma
that were treated before freezing. Methods. The examination included 20 units
of plasma, separated from whole blood donated by voluntary blood donors
around 6 hours from the moment of collection. The units were pooled and
separated in to two groups: one consisted of 10 control units and the other
of 10 experimental units. Experimental units of the plasma were treated by
riboflavin (35 mL) and UV rays (6.24 J/mL, 265-370 nm) on Mirasol aparature
(Caridian BCT Biotechnologies, USA) in approximate duration of 6 minutes.
Furthermore, 35 mL of saline solution was added to the control plasma. One
sample for examining was taken from the control plasma (KG) and two residual
were taken from experimental plasma after the addition of riboflavin either
before (EG1) or post illumination (EG2). Results. Comparing the mean values
of FVIII:C (%) we noticed statistically significantly higher level in the EG1
group than in the EG2 group (65.00 ? 4.52 vs 63.20 ? 4.73; t = 4.323, p =
0.002), while between the KG and experimental groups (EG1 and EG2) there was
no statistically significant difference in the concentration of FVIII:C.
There was a statistically significant decrease of albumin concentration (g/L)
in the EG2 group comparing to the KG (33.35 ? 0.94 vs 31.94 ? 0.84; t =
3.534, p = 0.002), but there was no mentioned difference in albumin
concentration between the KG and the EG1, so as between the EG1 and the EG2.
Conclusion. Plasma inactivated by riboflavin and UV rays (Mirasol PRT sistem,
Caridian BCT, USA) keeps all the characteristics of conventional plasma, so
it could be used for the treatment of pathological conditions that demand
transfusion of fresh frozen plasma, or in patients with thrombotic
thrombocytopenic purpure when we use therapeutic exchange of plasma.
Early serum biomarkers of ischemic stroke
Authors: Zivkovic Miroslava , Ljubisavljevic Srdjan
Published: January 2011

nema
Epileptic seizure as the first sign of hypoparathyroidism
Authors: Pesic Milica , Radojkovic Danijela , Radenkovic Sasa , Spasic Mirjana , Lukic Stevo
Published: January 2011

Background. Hypoparathyroidism refers to a group of disorders in which
extracellular calcium levels cannot be maintained within the normal range due
to relative or absolute deficiency of parathyroid hormone (PTH). The clinical
features of hypoparathyroidism are consistent with hypocalcaemia and,
predominantly, neuromuscular dysfunction. Although hypocalcaemia-induced
seizures are well documented hypoparathyroidism-induced epilepsy is often
misdiagnosed as idiopathic epilepsy. Case report. We reported a 57-year-old
woman with new-onset seizure due to hypoparathyroidism. At first, diagnosis
of epilepsy was established and the antiepileptic therapy was initiated with
gradual increase of the dose. Computerized tomography scan of the head
revealed bilateral basal ganglia and cerebellar calcification and many
punctiform calcifications between cortical and subcortical parts. During
hospitalization, laboratory tests showed hypocalcemia, hyperphosphatemia and
low PTH level. Once the diagnosis of hypoparathyroidism was established, a
proper treatment with calcium and vitamin D was started, and the patient was
discharged from hospital with full seizure control. Conclusion. Standard
evaluation of serum calcium levels in patients with new-onset epileptic
seizures should be obligatory part of a diagnostic algoritam to avoid
misdiagnosis of idiopathic epilepsy.
Why Victory in the War on Cancer Remains Elusive: Biomedical Hypotheses and Mathematical Models
Authors: Hanin Leonid
Published: January 2011

We discuss philosophical, methodological, and biomedical grounds for the traditional paradigm of cancer and some of its critical flaws. We also review some potentially fruitful approaches to understanding cancer and its treatment. This includes the new paradigm of cancer that was developed over the last 15 years by Michael Retsky, Michael Baum, Romano Demicheli, Isaac Gukas, William Hrushesky and their colleagues on the basis of earlier pioneering work of Bernard Fisher and Judah Folkman. Next, we highlight the unique and pivotal role of mathematical modeling in testing biomedical hypotheses about the natural history of cancer and the effects of its treatment, elaborate on model selection criteria, and mention some methodological pitfalls. Finally, we describe a specific mathematical model of cancer progression that supports all the main postulates of the new paradigm of cancer when applied to the natural history of a particular breast cancer patient and fit to the observables.
Wavelet-Based Analysis on the Complexity of Hydrologic Series Data under Multi-Temporal Scales
Authors: Sang Yan-Fang , Wang Dong , Wu Ji-Chun , Zhu Qing-Ping , Wang Ling
Published: January 2011

In this paper, the influence of four key issues on wavelet-based analysis of hydrologic series’ complexity under multi-temporal scales, including the choice of mother wavelet, noise, estimation of probability density function and trend of series data, was first studied. Then, the complexities of several representative hydrologic series data were quantified and described, based on which the performances of four wavelet-based entropy measures used commonly, namely continuous wavelet entropy (CWE), continuous wavelet relative entropy (CWRE), discrete wavelet entropy (DWE) and discrete wavelet relative entropy (DWRE) respectively, were compared and discussed. Finally, according to the analytic results of various examples, some understanding and conclusions about the calculation of wavelet-based entropy values gained in this study have been summarized, and the corresponding suggestions have also been proposed, based on which the analytic results of complexity of hydrologic series data can be improved.
High Photoelectric Conversion Efficiency of Metal Phthalocyanine/Fullerene Heterojunction Photovoltaic Device
Authors: Lin Chi-Feng , Zhang Mi , Liu Shun-Wei , Chiu Tien-Lung , Lee Jiun-Haw
Published: January 2011

This paper introduces the fundamental physical characteristics of organic photovoltaic (OPV) devices. Photoelectric conversion efficiency is crucial to the evaluation of quality in OPV devices, and enhancing efficiency has been spurring on researchers to seek alternatives to this problem. In this paper, we focus on organic photovoltaic (OPV) devices and review several approaches to enhance the energy conversion efficiency of small molecular heterojunction OPV devices based on an optimal metal-phthalocyanine/fullerene (C60) planar heterojunction thin film structure. For the sake of discussion, these mechanisms have been divided into electrical and optical sections: (1) Electrical: Modification on electrodes or active regions to benefit carrier injection, charge transport and exciton dissociation; (2) Optical: Optional architectures or infilling to promote photon confinement and enhance absorption.
Carotenoids in Fruits of Different Persimmon Cultivars
Authors: Zhou Chunhua , Zhao Daqiu , Sheng Yanle , Tao Jun , Yang Yong
Published: January 2011

Carotenoids in the peel and the flesh of persimmon fruit were identified, and the contents of carotenoids in the fleshes of 46 different persimmon cultivars were analyzed. The results indicated that 31 specific carotenoids were detected in both cultivars of persimmons, among which nine specific carotenoids were characterized. β-Cryptoxanthin was the most abundant carotenoid among all individual components in both the peel and the flesh, accounting for about 20-30% of the total carotenoids in both cultivars. The contents of total carotenoids in the fleshes of different persimmon cultivars were between 194.61 µg/100g FW and 1,566.30 µg/100g FW. Zeaxanthin was also the most abundant in all persimmon fleshes besides β-Cryptoxanthin, and the total amount of these two components accounted for 37.84-85.11% of the total carotenoids. The RE values in the fleshes of different cultivars also differed greatly. Besides, the stage of maturation was also important factor which could influence the carotenoid content and RE value in the fleshes.
Changes in Population Dynamics in Mutualistic versus Pathogenic Viruses
Authors: Roossinck Marilyn J.
Published: January 2011

Although generally regarded as pathogens, viruses can also be mutualists. A number of examples of extreme mutualism (i.e., symbiogenesis) have been well studied. Other examples of mutualism are less common, but this is likely because viruses have rarely been thought of as having any beneficial effects on their hosts. The effect of mutualism on the population dynamics of viruses is a topic that has not been addressed experimentally. However, the potential for understanding mutualism and how a virus might become a mutualist may be elucidated by understanding these dynamics.
Les occupations mésolithiques de la pointe Saint-Gildas à Préfailles (Loire-Atlantique) dans leur cadre paléoenvironnemental
Authors: Dupont Catherine , Marchand Grégor , Gruet Yves , Tessier Michel
Published: January 2011

Zusammenfassung. Bei den seit 1954 auf der Pointe Saint-Gildas (Préfailles, Département Loire-Atlantique), an der Mündung der Loire durchgeführten Prospektionen konnten drei mesolithische Siedlungsplätze lokalisiert werden, die sich durch eine auf der Herstellung regelmäßiger Lamellen basierende Steinbearbeitung auszeichnen. Die Linsen aus schwarzer Erde enthielten Muschelschalen (überwiegend Scrobicularia), die sich nach dem Verzehr der Meeresfrüchte durch die Menschen hier angesammelt hatten. 1994 wurden auf dem Fundplatz 1a und 2003 und 2004 auf dem Fundplatz 1b Grabungen durchgeführt, bei denen das Material systematisch gesiebt wurde. Die Muscheln weisen auf ein schlickiges Milieu, während die Fundstätten heute einen felsigen Gezeitenbereich überragen. Die Flandrische Transgression hat eine Flussmündung überdeckt (ria de Pornic), die anhand bathymetrischer Messungen und Kernbohrungen in den Sedimenten unter dem Meer nachgewiesen werden konnte. Die Datierung von Muschelschalen von Saint-Gildas 1b ergibt eine Spanne zwischen 6600 und 6400 v. Chr., was einer älteren Datierung von vor über 30 Jahren nicht widerspricht. Sie wurden mit Klingen und breiten Lamellen mit sinuösen Graten gefunden, bei denen breite ungleichschenkelige Dreiecke überwiegen, wo aber auch asymmetrische Trapeze vorkommen. Die Erosion der Fundstätten und die schwierige Kalibrierung dieser Datierungen bringen viele Ungenauigkeiten mit sich, es kann aber davon ausgegangen werden, dass es sich bei diesen Fundkomplexen um die ersten Beispiele der Herausbildung des Spätmesolithikums (Mesolithikum mit Trapezen) im armorikanischen Massiv handelt. Übersetzung: Isa Odenhardt-Donvez
Kinetic lattice Monte-Carlo simulations on the ordering kinetics of free and supported FePt L10-nanoparticles
Authors: Müller Michael , Albe Karsten
Published: January 2011

The ordering kinetics in free and supported L10 nanoparticles was studied by means of lattice-based kinetic Monte-Carlo simulations. Starting from a fully disordered particle of Wulff shape, the simulations show that the nucleation of ordered domains is starting quickly on various (100) facets but is retarded in the particle volume due to the lack of vacancies compared with a thin film geometry. If a substrate is present, we do not find significant differences in the ordering behavior. This holds true, even if we impose a massively increased thermodynamic driving force for interface segregation, because the nucleation of ordered domains on free facets is significantly faster than the bulk diffusion of the segregating species to the interface. In cases where wetting of the substrate or surface facetting occurs, we find that diffusional atomic motion on the surface goes along with an enhanced long-range order.
Applied magnetic field and stress induced anisotropy dependence of energy for oriented ferromagnetic thick films
Authors: Samarasekara P
Published: January 2011

The energy of perfectly oriented thick ferromagnetic films at different applied magnetic field and stress was studied using classical model of Heisenberg Hamiltonian. For the values of parameters used in this report, the energy required to orient the film with 1000 layers in 41.4° or 57.6° directions becomes minimum at applied magnetic fields of Hout/ω = 4.8 or Hin/ω = 4.8, respectively. The film can be easily oriented in 172° direction by applying the external stress Ks/ω = 3.6 perpendicular to the film plane, for the values of parameters used in this report. These final results mainly depend on the values of other parameters used for calculations. The energy becomes minimum and maximum at almost the same values of oriented angle (θ), in plane magnetic field, out of plane magnetic field and stress for both sc(001) and bcc(001 lattice types. But the values of energies corresponding to maxima and minima are slightly different for the sc(001) and bcc(001) lattices.Keywords: Magnetic thin films; ferromagnetism; Heisenberg Hamiltonian; stress induced anisotropy and spin DOI: 10.4038/josuk.v4i0.2692J Sci.Univ.Kelaniya 4 (2008): 1-10
Exact formula for the sum of the squares of the Bessel function and the Neumann function of the same order of half-odd integer
Authors: Piyadasa RAD , Arachchi DK Mallawa
Published: January 2011

Sum of the squares of the Bessel function and the Neumann function of the same order of half-odd integer has been found to be very useful in addressing a puzzle in nuclear physics. One approximate formula available in the literature is valid for the complex argument whose real part is greater than zero, and the absolute value of error term is undefined for half-odd integers. Another approximate formula which is valid for all complex arguments has been obtained using sophisticated mathematical method called Barnes' method. However, the error in the formula is very difficult to calculate. We have obtained exact formula for the sum of the squares of Bessel and Neumann functions of the same order of half-odd integers which is valid for all complex arguments, and its proof is also given.Keywords: Bessel functions; Neumann functions; Anomalous absorption; Partial waves DOI: 10.4038/josuk.v4i0.2694J Sci.Univ.Kelaniya 4 (2008): 15-20
Determination of phase transitions in Y-shaped, branched alkane, C120H241CH(C195H391)C119H23 using Raman spectroscopy
Authors: Wickramarachchi PA Suranga L , Spells Stephen J
Published: January 2011

Raman spectroscopy has been used to identify solid – solid phase transitions in the symmetrically branched alkane, C120H241CH(C195H391)C119H23  during real-time heating. The vibrational modes in the region from 1700 to 200 cm-1 were studied. A single phase transition was identified at 87°C ± 5°C in this alkane based on the changes in the band intensities. It was revealed that the crystalline bands show subtle changes whereas the disorder bands show the most significant changes at this transition. Key words: Monodisperse alkanes; vibrational spectroscopy; crystal structuresDOI: 10.4038/josuk.v4i0.2696J Sci.Univ.Kelaniya 4 (2008): 36-45
Physical interpretation of anomalous absorption of partial waves by nuclear optical potential
Authors: Piyadasa RAD , Munasinghe J , Karunatileke NGA
Published: January 2011

Anomalous absorption of light ion partial waves by the nuclear optical potential is an interesting phenomenon showing striking systematic in various parameter planes. However, the theoretical description of this phenomenon is extremely difficult. In this contribution, we address the problem of its physical interpretation. It is shown that the zero of the S-matrix element associated with the anomalous absorption of a partial wave is due to the destructive interference of the reflected waves, from the innermost turning point and the outermost turning point, in the asymptotic region when WKB approximation is feasible.Key words: anomalous absorption; Partial waves; S-matrix element. DOI: 10.4038/josuk.v4i0.2698J Sci.Univ.Kelaniya 4 (2008): 68-72
Service technologies creates a tangible link for value generation: service economy in Sri Lanka
Authors: Ekanayake Shyamalie , Abeysinghe Dhammika
Published: January 2011

A country’s ability to develop a competitive service economy depends on its production sector, as they demand use of services. Continuous improvement or innovation in technologies in both manufacturing and services will simultaneously increase smooth flow of operations for competitiveness by lowering cost of production to enhance customer satisfaction, to attain value. The success of different industries depends on how well the service sector is geared to support them.  To carry out better management strategies for value gain, it is necessary to provide a tangible link to integrate the production and distribution channels for efficiency and effectiveness of the organizational and technological dimensions.  Technology transfer and continuous innovation of systems enhances productivity growth for cost competitiveness leading to better prices, responsiveness and flexibility of the processes to deliver a quality product to changing markets. The research purpose is therefore to identify management strategies and service technologies to analyze the characteristics of research variables in relation to GDP value generating sectors and focus on issues relating to value.   Key words:  resources; service technology; integration; value.DOI: 10.4038/josuk.v4i0.2699J Sci.Univ.Kelaniya 4 (2008): 73-94
Discrete Series for p-adic SO(2n) and Restrictions of Representations of O(2n)
Authors: Jantzen Chris
Published: January 2011

In this paper we give a classification of discrete series for SO(2n, F), F p-adic, similar to that of Mœglin–Tadić for the other classical groups. This is obtained by taking the Mœglin–Tadić classification for O(2n, F) and studying how the representations restrict to SO(2n, F). We then extend this to an analysis of how admissible representations of O(2n, F) restrict.
Automotive Safety Handbook, Second Edition
Authors:   TUV Automotive, Wech Lothar , Seiffert Ulrich W ,   Witech Engineering GmbH
Published: January 2011

Examining the state-of-the-art in passenger car vehicle safety, the book features thorough discussion of the interrelationships among the occupant, the vehicle, and the restraint system (in frontal, lateral, and rear impacts and rollover).
Engineering Plastics and Plastic Composites in Automotive Applications
Authors:   Dow Chemical Co., Sehanobish Kalyan
Published: January 2011

Before the 1970s, plastics were considered primarily as non-engineering materials and were used in applications such as belts, hoses, gaskets, carpet backing, sealing, adhesives, tires, and so forth as a part of an engineering solution. More recently, plastics have replaced traditional materials and emerged as a significant "engineering application" within the automotive industry. Plastics have proven to be cost effective while providing automakers with the design freedom to accommodate safety, styling, and comfort. Engineering Plastics and Plastic Composites In Automotive Applications focuses on some of the various types of plastics and plastic composites and their applications and advantages within passenger vehicles.
A regional real-time forecast of marine boundary layers during VOCALS-REx
Authors: Wang S. , O'Neill L. W. , Jiang Q. , de Szoeke S. P. , Hong X. , Jin H. , Thompson W. T. , Zheng X.
Published: January 2011

Abstract. This paper presents an evaluation and validation of the Naval Research Laboratory's COAMPS® real-time forecasts during the VOCALS-REx over the area off the west coast of Chile/Peru in the Southeast Pacific during October and November 2008. The analyses focus on the marine boundary layer (MBL) structure. These forecasts are compared with lower troposphere soundings, in situ surface measurements, and satellite observations. The predicted mean MBL cloud and surface wind spatial distributions are in good agreement with the satellite observations. The large-scale longitudinal variation of the MBL structure along 20° S is captured by the forecasts. That is, the MBL height increases westward toward the open ocean, the moisture just above the inversion decreases, and the MBL structure becomes more decoupled offshore. The observed strong wind shear across the cloud-top inversion near 20° S was correctly predicted by the model. The model's cloud spatial and temporal distribution in the 15 km grid mesh is sporadic compared to satellite observations. Our results suggest that this is caused by grid-scale convection likely due to a lack of a shallow cumulus convection parameterization in the model. Both observations and model forecasts show wind speed maxima near the top of MBL along 20° S, which is consistent with the westward upslope of the MBL heights based on the thermal wind relationship. The forecasts produced well-defined diurnal variations in the spatially-averaged MBL structure, although the overall signal is weaker than those derived from the in situ measurements and satellite data. The MBL heights are generally underpredicted in the nearshore area. An analysis of the sensitivity of the MBL height to horizontal and vertical grid resolution suggests that the underprediction is likely associated with overprediction of the mesoscale downward motion and cold advection near the coast.
Influence of convection and aerosol pollution on ice cloud particle effective radius
Authors: Jiang J. H. , Su H. , Zhai C. , Massie S. T. , Schoeberl M. R. , Colarco P. R. , Platnick S. , Gu Y. , Liou K.-N.
Published: January 2011

Abstract. Satellite observations show that ice cloud effective radius (re) increases with ice water content (IWC) but decreases with aerosol optical thickness (AOT). Using least-squares fitting to the observed data, we obtain an analytical formula to describe the variations of re with IWC and AOT for several regions with distinct characteristics of re-IWC-AOT relationships. As IWC directly relates to convective strength and AOT represents aerosol loading, our empirical formula provides a means to quantify the relative roles of dynamics and aerosols in controlling re in different geographical regions, and to establish a framework for parameterization of aerosol effects on re in climate models.
Aerosol particle number size distributions and particulate light absorption at the ZOTTO tall tower (Siberia), 2006–2009
Authors: Heintzenberg J. , Birmili W. , Otto R. , Andreae M. O. , Mayer J.-C. , Chi X. , Panov A.
Published: January 2011

Abstract. This paper covers measurements of the number-size distribution of aerosol particles, particulate absorption at 570 nm wavelength and CO as tracer gas from 2006 through 2009 at 50 and 300 m on the ZOTTO tower, Siberia at 60.8° N; 89.35° E. Average number, surface and volume concentrations are similar to results given for continental and boreal background locations. When fitted with lognormal functions, the probability distribution function of modal diameters shows three main maxima in the Aitken and accumulation size range and a possible secondary maximum in the nucleation size range below 25 nm. The seasonal distributions of the different particle parameters differ substantially. Particulate absorption has a clear single maximum in high winter and minimum values in mid-summer. The 90%-percentile, however, indicates a possible secondary maximum in July/August that may be related to forest fires. The strongly combustion derived CO shows a single winter maximum and a late summer minimum, albeit with a considerable smaller seasonal swing than the particle data due to its longer atmospheric lifetime. Total volume and even more so total number show a more complex seasonal variation with maxima in winter, spring, and summer. A cluster analysis of back trajectories complemented by local stability information yielded ten clusters with three levels of particle concentration: Low concentrations for the northernmost (Arctic) clusters mid-level concentrations for clusters reaching rapidly west between 55° and 65° latitude, and high concentrations for the cluster reaching southwest via Kazakhstan to the central Russian industrial region.
Quantification of aerosol chemical composition using continuous single particle measurements
Authors: Jeong C.-H. , McGuire M. L. , Godri K. J. , Slowik J. G. , Rehbein P. J. G. , Evans G. J.
Published: January 2011

Abstract. Mass concentrations of particulate matter (PM) chemical components were determined from data for 0.3 to 3.0 μm particles measured by an Aerosol Time-of-Flight Mass Spectrometer (ATOFMS) data at an urban and rural site. Hourly-averaged concentrations of nitrate, sulphate, ammonium, organic carbon, and elemental carbon, estimated based on scaled ATOFMS peak intensities of corresponding ion marker species, were compared with collocated chemical composition measurements by an Aerosol Mass Spectrometer (AMS), a Gas-Particle Ion Chromatograph (GPIC), and a Sunset Lab field OCEC analyzer. The highest correlation was found for nitrate, with correlation coefficients (Pearson r) of 0.89 and 0.85 at the urban and rural sites, respectively. ATOFMS mass calibration factors, determined for the urban site, were used to calculate mass concentrations of the major PM chemical components at the rural site. Mass reconstruction using this ATOFMS based composition data agreed very well with the total PM mass measured at the rural site. Size distributions of the ten main types of particles were resolved for the rural site and the mass composition of each particle type was determined in terms of sulphate, nitrate, ammonium, organic carbon and elemental carbon. This is the first study to estimate hourly mass concentrations of individual aerosol components and the mass composition of individual particle-types based on ATOFMS single particle measurements.
Analysis of cloud condensation nuclei composition and growth kinetics using a pumped counterflow virtual impactor and aerosol mass spectrometer
Authors: Slowik J. G. , Cziczo D. J. , Abbatt J. P. D.
Published: January 2011

Abstract. We present a new method of determining the size and composition of CCN-active aerosol particles. Method utility is illustrated through a series of ambient measurements. A continuous-flow thermal-gradient diffusion chamber (TGDC), pumped counterflow virtual impactor (PCVI), and Aerodyne time-of-flight mass spectrometer (AMS) are operated in series. Ambient particles are sampled into the TGDC, where a constant supersaturation is maintained, and CCN-active particles grow to ~2.5±0.5 μm. The output flow from the TGDC is directed into the PCVI, where a counterflow of dry N2 gas opposes the particle-laden flow, creating a region of zero velocity. This stagnation plane can only be traversed by particles with sufficient momentum, which depends on their size. Particles that have activated in the TGDC cross the stagnation plane and are entrained in the PCVI output flow, while the unactivated particles are diverted to a pump. Because the input gas is replaced by the counterflow gas with better than 99% efficiency at the stagnation plane, the output flow consists almost entirely of dry N2 and water evaporates from the activated particles. In this way, the system yields an ensemble of CCN-active particles whose chemical composition and size are analyzed using the AMS. Measurements of urban aerosol in downtown Toronto identified an external mixture of CCN-active particles consisting almost entirely of ammonium nitrate and ammonium sulfate, with CCN-inactive particles of the same size consisting of a mixture of ammonium nitrate, ammonium sulfate, and organics. We also discuss results from the first field deployment of the TGDC-PCVI-AMS system, conducted from mid-May to mid-June 2007 in Egbert, Ontario, a semirural site ~80 km north of Toronto influenced both by clean air masses from the north and emissions from the city. Organic-dominated particles sampled during a major biogenic event exhibited higher CCN activity and/or faster growth kinetics than urban outflow from Toronto, despite the latter having a higher inorganic content and higher O:C ratio. During both events, particles were largely internally mixed.
Implications of the permanent El Niño teleconnection "blueprint" for past global and North American hydroclimatology
Authors: Goldner A. , Huber M. , Diffenbaugh N. , Caballero R.
Published: January 2011

Abstract. Substantial evidence exists for wetter-than-modern continental conditions in past warm climates. This is in apparent conflict with the robust global prediction for future climate change of a northward expansion of the subtropical dry zones that should drive aridification of many semiarid regions. Areas of expected aridification include much of Western North America, where extensive paleoenvironmental records from North America point to wetter conditions before the onset of Quaternary ice ages. It has been proposed that climates previous to the early Pliocene may have been characterized as being in a state with warmer-than-modern eastern equatorial sea surface temperatures (SSTs). Because Equatorial Pacific SSTs exert strong controls on midlatitude atmospheric circulation and the global hydrologic cycle, the teleconnected response from this permanent El Niño-like mean state has been proposed as a useful analogue model, or "blueprint", for understanding global climatological and hydrological anomalies in the past. The present study quantitatively explores the implications of this blueprint for past climates, using a global climate model (CAM3.0) and a nested high-resolution climate model (RegCM3) to study the hydrologic impacts of a permanent El Niño on global and North American climate. We find that the global circulation response to a permanent El Niño resembles a large, long El Niño event. However, this state also exhibits equatorial super-rotation, which would represent a fundamental change to the tropical circulations. We also find intensification and southward drift in winter storm tracks in the Pacific, which affects precipitation and temperature over the mid-latitudes via large shifts in atmospheric circulation. In addition, summertime precipitation increases over the majority of the continental United States, with these increases likely controlled by shifts in the subtropical jet and secondary atmospheric feedbacks. Based on these results, we conclude that a permanent El Niño is a good explanation of the Pre-Quaternary wetter-than-modern conditions observed in paleo proxy records, particularly over the Western United States.
Water supply project feasibilities in fringe areas of Kolkata, India
Authors: Dutta Roy K. , Thakur B. , Konar T. S. , Chakrabarty S. N.
Published: January 2011

Abstract. Water supply management to the peri-urban areas of the developing world is a complex task due to migration, infrastructure and paucity of fund. A cost-benefit methodology particularly suitable for the peri-urban areas has been developed for the city of Kolkata, India. The costs are estimated based on a neural network estimate. The water quality of the area is estimated from samples and a water quality index has been prepared. A questionnaire survey in the area has been conducted for relevant information like income, awareness and willingness to pay for safe drinking water. A factor analysis has been conducted for distinguishing the important factors of the survey and subsequent multiple regressions have been conducted for finding the relationships for the willingness to pay. A system dynamics model has been conducted to estimate the trend of increase of willingness to pay with the urbanizations in the peri-urban areas. A cost benefit analysis with the impact of time value of money has been executed. The risk and uncertainty of the project is investigated by Monte Carlos simulation and tornado diagrams. It has been found that the projects that are normally rejected in standard cost benefit analysis would be accepted if the impacts of urbanizations in the peri-urban areas are considered.
A plateau scale soil moisture and soil temperature observatory for quantifying uncertainties in coarse resolution satellite products
Authors: Su Z. , Wen J. , Dente L. , van der Velde R. , Wang L. , Ma Y. , Yang K. , Hu Z.
Published: January 2011

Abstract. A plateau scale soil moisture and soil temperature observatory is established on the Tibetan Plateau for quantifying uncertainties in coarse resolution satellite products of soil moisture and soil temperature. The observatory consists of three regional networks across the Tibetan Plateau and provides reliable measurements of mean and variance in soil moisture and soil temperature of representative areas comparable in size to coarse satellite footprints. Using these in-situ measurements, a analysis is carried out to assess the reliability of several satellite products derived from AMSR-E and ASCAT data by three retrieval algorithms (henceforth the AMSR-E products, the ASCAT-L2 products and the ITC-model retrievals) for the first time. For the cold semiarid Naqu area, AMSR-E and ASCAT-L2 products overestimate significantly the regional soil moisture in the monsoon seasons. The ITC-model retrievals are closer to the in-situ measurements but the dynamics in the retrieved time series needs further investigation. The use of these datasets is therefore not recommended for cold semiarid conditions on the Tibetan Plateau. For the cold humid Maqu network area AMSR-E and ASCAT-L2 products have comparable accuracy as reported by previous studies in the humid monsoon period. AMSR-E products significantly overestimate and ASCAT-L2 products underestimate the soil moisture in the winter period. The ITC-model retrievals underestimate the soil moisture in general. It is concluded that global coarse resolution soil moisture products are useful but exhibit till now unreported uncertainties in cold and semiarid regions – use of them would be critically enhanced if uncertainties can be quantified and reduced using in-situ measurements.
Hepatitis
B
Virus
Authors: Jilbert Allison R , Reaiche Georget Y , Clouston Andrew , Mason William S
Published: January 2011

Human

hepatitis B virus

(HBV) is the prototype member of the
Hepadnaviridae
family of viruses, characterised by a relaxed circular, ∼3200‐bp
deoxyribonucleic acid
(DNA) genome (rcDNA) with replication primarily in hepatocytes, the major parenchymal cell of the liver. HBV infections may be transient or chronic. All hepadnaviruses, including those that infect humans as well as small animal species, are similar clinically and biologically. Part of the replication strategy includes conversion of the rcDNA genome into covalently closed circular DNA (cccDNA), which is found exclusively in the nucleus of infected hepatocytes. This cccDNA acts as template for the transcription of all hepadnaviral messenger
ribonucleic acids
(mRNAs). One of the largest mRNAs, the pregenome, is reverse transcribed in the cytoplasm into new rcDNA. cccDNA is a highly stable molecule present as a mini chromosome with up to 10–50 copies in the nucleus of each infected hepatocyte. The stability of cccDNA, the noncytolytic nature of infection and the fact that hepatocytes constitute a self‐renewing population make chronic HBV infections difficult to treat. The natural course of chronic HBV infection consists of four phases: immune tolerance, immune clearance, immune control and reactivation and is associated with liver disease that encompasses a wide range of histological changes.

Key Concepts:

There are two possible outcomes of HBV infection: transient or chronic infection.

Transient (acute) HBV infections often spread to infect >95% of hepatocytes and can be rapidly cleared from the liver.

Ninety to ninety‐five percent of adults experience transient infections, whereas 30–90% of children develop chronic HBV infections.

Chronic HBV infection can result in liver disease including portal and lobular inflammation, fibrosis, cirrhosis and hepatocellular carcinoma (HCC).

Multiple copies of cccDNA are present in each infected hepatocyte and act as a stable reservoir for HBV infection.

The highly stable nature of cccDNA is the major factor in the failure of antiviral therapy during chronic HBV infection.

Pre‐exposure vaccination with HBV surface antigen (HBsAg) particles results in an anti‐HBs antibody response that provides immunity against HBV infection.

HBV remains a major worldwide problem with >360 million people with chronic infection.
Beneden, Edouard Van
Authors: Van Dyck Marie Claire
Published: January 2011

The Belgian biologist Edouard Van Beneden (1846–1910) had a successful scientific career. His dissertation demonstrating the omnipresence in the whole animal kingdom, of the egg's unicellular constitution was awarded by the prize of the Royal Academy of Belgium. In 1870, he became professor at the University of Liège and corresponding member of the Royal Academy of Belgium and became chartered member in 1872.

Using cytology in embryology and selecting a suitable material to study the fertilisation, he was the first to observe meiosis, described the centrosome and understood the very early polarisation of the egg.
Protein: Cotranslational and Posttranslational Modification in Organelles
Authors: Shandala Tetyana , Parkinson‐Lawrence Emma J , Brooks Doug A
Published: January 2011

Polypeptides can be modified in the rough endoplasmic reticulum (RER) either during their synthesis (cotranslational) or after the initial synthesis has been completed (posttranslational). These structural modifications are also referred to as protein processing events, which can includeN‐linked glycosylation;O‐linked glycosylation; glycolipid attachment; disulfide bond formation to generate secondary structure; modification to fold the polypeptide into a stable tertiary structure (low free energy state) and proteolytic processing of the nascent polypeptide or precursor protein to generate either protein subunits or mature functional protein. Cotranslational and posttranslational modification is therefore critical for generating stable protein structure and ultimately appropriate function. Protein processing is also used to generate appropriate targeting signals, which, following synthesis, are used to traffic each protein to either its correct subcellular compartment or extracellular destination.

Key Concepts:

Transcribed mRNA contains the code for polypeptide synthesis, which is exported from the nucleus to the cytoplasm to initiate protein translation.

For noncytosolic proteins, the mature mRNA is bound by ribosomes in the cytoplasm, to synthesise a signal sequence, and this complex is then transported to the RER for additional polypeptide synthesis.

Newly synthesised polypeptides undergo cotranslational modification in the RER.

N‐linked glycosylation is an essential structural component that is added to the nascent polypeptide in the RER and is involved in the initial steps of protein folding.

Molecular chaperones in the RER facilitate protein folding to generate correct protein secondary and tertiary structure.

There is a quality control process to ensure that only correctly folded and processed proteins exit the RER.

Posttranslational modifications can take place in different cellular organelles such as the RER, Golgi, endosomes, lysosomes and secretory vesicles.

The Golgi is involved in posttranslational glycoprocessing and the generation of signals for targeting protein to its final destination.

Posttranslational proteolytic processing can be used to generate protein subunits and mature functional proteins.
‘Race’: What Biology Can Tell Us about a Social Construct
Authors: Kaplan Jonathan Michael
Published: January 2011

Although there exist human populations that differ in the proportions of particular alleles present, this fact does not support claims that ‘race’, as it is usually understood, is a biological rather than a social concept. Although there are differences in proportions of alleles in those races usually recognised in contemporary western social discourse (folk‐racial categories), these differences are no more
biologically
significant than are the genetic differences that exist between populations that are
not
socially recognised as races (populations that do not correspond to folk‐racial categories). This implies that whatever average genetic differences exist between the populations called ‘races’ in ordinary social discourse, those genetic differences are
not
what account for the folk‐racial categories in use today. Despite recent research sometimes taken to imply otherwise, folk‐racial categories – which remain of fundamental importance to people's life‐prospects – remain social categories and not biological categories.

Key Concepts:

Many human populations differ from each other in the frequencies of particular alleles.

Many of these genetic variations between human populations can be explained by population structure.

Contemporary socially identified racial categories (folk‐racial categories) can be mapped (albeit only roughly) onto human populations identified on the basis of the continental location of recent ancestors.

Since physical location is associated with population structure, it is no surprise that populations whose ancestors came from different locations will differ in the frequencies of some alleles.

Although human populations identified on the basis of folk‐racial categories differ in the proportion of particular alleles, so too do many human populations that are not generally socially recognised as forming races (such as the country of origin within Europe).

Biologically, the populations that form folk‐racial categories (e.g. Asians) are no more important or significant than many other populations that are not usually identified as races (e.g. the Spanish and Portuguese).

Although human populations identified on the basis of folk‐racial categories differ in the proportion of particular alleles, this does not make the folk‐racial categories biological categories.
Mucopolysaccharide Storage Disorders
Authors: Filocamo Mirella , Cooper David N , Di Rocco Maja
Published: January 2011

The mucopolysaccharidoses (MPSs) are a group of 11 distinct metabolic disorders that result from the deficiency of the various lysosomal enzymes required to degrade the glycosaminoglycans (GAGs) that constitute a major component of the extracellular matrix, joint fluid and connective tissue. The progressive lysosomal accumulation of GAGs ultimately impairs joint mobility and adversely affects the skeleton and cardiovascular system. Depending on the type or subtype of mucopolysaccharidosis, mental development may range from normal to profoundly impaired. Enzymatic and molecular diagnostic testing are available for all the MPSs. Hematopoietic stem cell transplantation (HSCT) and enzyme replacement therapy (ERT) are the only specific treatments for MPS currently available.

Key Concepts:

The degradation of glycosaminoglycans (or mucopolysaccharides) takes place in lysosomes that contain the acid hydrolases.

The deficiency of any one of 11 acid hydrolases, required to normally degrade the glycosaminoglycans, gives rise to the group of lysosomal storage disorders known as the mucopolysaccharidoses.

The progressive accumulation of glycosaminoglycans, a major component of the extracellular matrix, joint fluid and connective tissue, leads ultimately to multisystem involvement including organomegaly, dysostosis multiplex and abnormal facies.

The observation that the fraction of lysosomal enzymes that does not enter the lysosome is secreted from the cell and can be recaptured from other cells, suggests that lysosomal storage disorders are potentially treatable by enzyme replacement therapy.
Trypsin‐like Serine Proteases and the Evolution of Hematophagy in Mosquitoes
Authors: Wu Dong‐Dong , Zhang Ya‐Ping
Published: January 2011

Mosquitoes are scourge of humanity because they transmit many diseases during blood sucking. Study on the genes associated with the process of hematophagy will be helpful for studying and controlling mosquito‐borne diseases.
Trypsin‐like serine protease
family is ubiquitous and evolves dynamically in animals, and plays an important role in the digestion of food. The gene family is expanded significantly in the mosquito genomes, and the expression level of these genes is elevated remarkably after blood meal, particularly these phylogenetically expanded genes. Positive Darwinian selection is considered to drive the evolution and diversification of
trypsin‐like serine protease
family, which probably contributes profoundly to the hematophagous trait in mosquitoes. The
trypsin‐like serine proteases
are potential good candidates to study the process of hematophagy in mosquitoes and the control of mosquito‐borne diseases.

Key Concepts:

Mosquitoes are scourge of humanity because they transmit many diseases.

Trypsin‐like serine protease family plays an important role in the food digestion, and is expanded in the mosquito genomes.

The expression level of genes in the family is elevated remarkably after blood meal in mosquito, particularly these phylogenetically expanded genes.

Therefore, the expansion of trypsin‐like serine protease family plays an important role in the evolution of hematophagy in mosquito.
NMRof Organocopper Compounds
Authors: Gärtner Tobias , Gschwind Ruth M.
Published: January 2011

Introduction

NMRStructure Determination of Organocopper Reagents

NMRSpectroscopy of Intermediate Complexes of Organocuprates

NMRStructure Elucidation inCu(I)‐Catalyzed Reactions

Conclusion

Acknowledgment
Electrochemistry of Organocopper Compounds
Authors: Jaworski Jan S.
Published: January 2011

Introduction

Electrochemical Synthesis of Organocopper Compounds

Electrochemical Stability of Organocopper Compounds

Concluding Remarks