bluuebunny/crossref_metadata_2025_split huggingface dataset:
Effects of Physical Aging on Thermal and Mechanical Properties of Glassy Normal Corn Starch
Authors: Chung Hyun‐Jung , Yoo Byoungseung , Lim Seung‐Taik 
Published: August 2005

AbstractPhysical aging of glassy corn starch and its effect on the physical properties of compressed starch bars were investigated by using differential scanning calorimetry (DSC), dynamic mechanical thermal analyzer (DMTA), and Instron texturometer. Amorphous corn starch samples were prepared by drying a starch paste, followed by compressing the dried powders to bar‐type specimens under heat (100°C, 1.38×107 Pa). These bars were then aged at 25°C for up to 22 days, after which thermal and mechanical characteristics were determined. There were progressive increases in glass transition temperature and relaxation enthalpy during the aging, which reached limiting values as structural equilibrium of the amorphous matrix was approached. The peak temperature of the relaxation endotherm (DSC thermogram) changed with time in a trend similar to the relaxation enthalpy. The storage modulus (DMTA) increased with aging time, but the peak intensity of tan δ decreased. The breaking strength (Instron texturometer) increased gradually with time of aging and reached a maximum. It has been demonstrated the relaxation kinetics for glassy amorphous corn starch can be characterized by both thermal and mechanical properties, such as relaxation enthalpy, storage modulus, and breaking strength.
Dependence of Thermodynamic Characteristics of Amylose‐Lipid Complex Dissociation on a Variety of Wheat
Authors: Nebesny Ewa , Kwaśniewska‐Karolak Izabella , Rosicka‐Kaczmarek Justyna 
Published: August 2005

AbstractNative wheat starch contains amylose‐lipid complexes (AMLs) that are formed both upon biosynthesis of native starch and upon heating of starch slurries at gelatinization temperature and above. These complexes have a detrimental impact on physicochemical properties of starch, because they reduce water binding by starch granules and retard their swelling. An objective of the presented work was to analyze the chemical composition of wheat starch and characterize the thermodynamics of gelatinization of different wheat starches and to evaluate the stability of AMLs derived from these starches with the aid of differential scanning calorimetry (DSC). Grains of eight wheat varieties were used throughout the studies. The gelatinization behavior of the eight wheat varieties examined was similar. The lowest temperature of the onset of gelatinization (Tk = 57.07°C) was found for the Jawa variety, and the highest (Tk = 60.58°C) for the Torka variety. Enthalpy of gelatinization (ΔHk) of the examined wheat starch preparations ranged from 9.14 J/g (Sakwa) to 11.95 J/g (Elena). Temperature and enthalpy of AMLs dissociation depended on wheat starch variety. During the first heating the temperature of the minimum of the endotherm (Td) ranged from 98.41°C to 100.5°C. During the second heating, the minimum was at slightly higher temperatures, varying from 102.02°C to 104.08°C. Enthalpies of AML dissociation (ΔHd) varied from 1.45 J/g to 2.14 J/g during the first heating. During the second heating the enthalpy values were slightly lower (1.26 J/g to 1.68 J/g). Enthalpies of AML reassociation ranged from 1.29 J/g to 1.72 J/g during the first cooling, and from 1.17 J/g to 1.63 J/g during the second cooling. A correlation was found between the amount of lipids and AML content.
Thermal and Pasting Properties of Microwaved Corn Starch
Authors: Stevenson David G. , Biswas Atanu , Inglett George E. 
Published: August 2005

AbstractCorn starch with 15–40% moisture was irradiated at 0.17 or 0.5 W/g for 1 h using the sophisticated Ethos 1600 microwave apparatus that accurately controls temperature and wattage. Temperature of irradiated starch was measured during microwaving. Thermal and pasting properties were studied on dehydrated starch after microwave irradiation. Temperature increases were greatest during the first 10 min for starch at all moisture contents at both microwave power levels. Starch irradiated at 0.17 W/g had a temperature below onset gelatinization temperature (To) after 1 h. Higher temperatures were observed for starch with higher moisture content and microwaved at 0.5 W/g. Compared to native starch, starch with 15–40% moisture had higher To (measured using differential scanning calorimetry) and with 35–40% moisture had higher peak gelatinization temperature and lower enthalpy change of gelatinization. All paste viscosity parameters measured by the Rapid Visco Analyser were reduced and pasting temperature was elevated for starch irradiated at 0.5 W/g compared to native starch.
Development of vacuum technology market in Russia. Entwicklung des Marktes für Vakuumtechnik in Russland
Authors: Rozanov L.N. 
Published: August 2005

AbstractScientific investigations of leak detection problems are being carried out in several directions. The most significant are metrology problems. Mathematical modeling of working processes in new types of leak detectors is also being developed. Mass spectrometer leak detectors remain the most popular for high accuracy measurements. Other types of leak detectors, such as halogen, manometer, and gas discharge, are also developing. Different types of gas discharge leak detectors are being manufactured.
Statistical characterization of the UWB propagation channel in indoor residential environment
Authors: Chong Chia‐Chin , Kim Young‐Eil , Yong Su Khiong , Lee Seong‐Soo 
Published: August 2005

AbstractThis paper presents a statistical characterization of an ultra wideband (UWB) indoor propagation channel based on measurements conducted in various types of high‐rise apartments in several cities of Korea. Measurements were carried out in the frequency band of 3–10 GHz. Various communication links were considered including both line‐of‐sight (LOS) and non‐LOS (NLOS) scenarios, which covered within‐the‐room and room‐to‐room propagations. The measurement procedure allows us to characterize both the large‐scale and the small‐scale statistics of the channel. The aim here is to study in more detail the statistical characteristics of the UWB propagation channel and to provide insight for future statistical channel modeling work. Channel characteristics examined include the distance and frequency dependency of path loss, shadowing fading statistics, and multipath temporal‐domain parameter statistics such as the mean excess delay, RMS delay spread, and the number of dominant paths. Copyright © 2005 John Wiley & Sons, Ltd.
Radio resource management in infrastructure‐based and ad hoc UWB networks
Authors: Giancol Guerino , Martello Cristina , Cuomo Francesca , Di Benedetto Maria‐Gabriella 
Published: August 2005

AbstractModeling the resource manager of an ultra wide band (UWB) network is the main object of this paper. The model is tested in two different application scenarios: (i) a UWB WLAN access network to a backbone where the resource management module is implemented at the access points (APs); (ii) a UWB ad hoc network for either local communications or data exchange among sensors, with peer‐to‐peer links with distributed management.The design must include a quality of service (QoS)‐aware strategy and must take into account coexistence issues raised by the use of UWB at the physical layer. Link quality is represented by the maximum end‐to‐end delay and minimum percentage of correct packets. From these parameters, the resource manager jointly selects the values of power and rate which must be adopted at the physical layer. In the model, radiated power by each device is supposed to be limited by an upper bound, reflecting thus the limitation imposed by regulation. QoS awareness and power constraints are satisfied, thanks to the implementation of an admission control function, which is centralized in the AP in the WLAN case and distributed in the ad hoc case. Major innovative aspects include: (i) taking into account UWB specific features; (ii) introducing QoS awareness based on network layer parameters rather than physical layer parameters; (iii) incorporating error protection functionalities for the optimization of transmission efficiency; (iv) considering both centralized and distributed resource management.Performance of the proposed resource manager module is evaluated in the presence of different classes of traffic, that is multimedia, voice, and data traffic. For each class of traffic, performance is expressed in terms of the maximum possible number of simultaneous connections for the WLAN case, and in terms of the effective achievable throughput for the ad hoc case. Results of simulations indicate that the behavior of the proposed scheme is strongly dependent upon the class of traffic in the WLAN scenario, while it is slightly affected by changes in traffic characteristics in the ad hoc case. Copyright © 2005 John Wiley & Sons, Ltd.
A joint PHY/MAC architecture for low‐radiated power TH‐UWB wireless ad hoc networks
Authors: Merz Ruben , Widmer Jörg , Le Boudec Jean‐Yves , Radunović Božidar 
Published: August 2005

AbstractDue to environmental concerns and strict constraints on interference imposed on other networks, the radiated power of emerging pervasive wireless networks needs to be strictly limited, yet without sacrificing acceptable data rates. Pulsed time‐hopping ultra‐wideband (TH‐UWB) is a radio technology that has the potential to satisfy this requirement. Although TH‐UWB is a multi‐user radio technology, non‐zero cross‐correlation between TH sequences, time‐asynchronicity between sources and a multipath channel environment make it sensitive to strong interferers and near‐far scenarios. While most protocols manage interference and multiple‐access through power control or mutual exclusion, we base our design on rate control, a relatively unexplored dimension for multiple‐access and interference management. We further take an advantage of the nature of pulsed TH‐UWB to propose an interference mitigation scheme that alleviates the need for an exclusion scheme. A source is always allowed to send and continuously adapts its channel code (hence its rate) to the interference experienced at the destination. In contrast to power control or exclusion, our MAC layer is local to sender and receiver, and does not need coordination among neighbors not involved in the transmission. We show by simulation that we achieve a significant increase in the network throughput compared to alternative designs. Copyright © 2005 John Wiley & Sons, Ltd.
Characterization of small planar antennas for UWB mobile terminals
Authors: Klemm Maciej , Tröster Gerhard 
Published: August 2005

AbstractThis paper presents an extensive investigations to characterize antennas for small UWB mobile terminals. Two small planar UWB antennas (slot antenna and printed monopole antenna) were designed, using a full‐wave electromagnetic finite difference time domain (FDTD) method. The UWB slot antenna has a size of 32 × 29 mm, the monopole antenna size is 20 × 36.75 mm. Both antennas were characterized usingtrueUWB parameters, such as antenna transfer functions, fidelity, and pulse energy spread. We have investigated angular‐dependence of antenna characteristics over the entire radiation sphere. Spatially averaged transfer functions were introduced to disclose antenna characteristics for different solid angles in the radiation sphere. We have also shown the difference in transient characteristics of antenna in transmitting (Tx) and receiving (Rx) mode. Finally, we have investigated the Tx/Rx antenna system, where any relative orientation between Tx and Rx antenna was assumed to be equally probable. Copyright © 2005 John Wiley & Sons, Ltd.
PUBLIC SCIENCE IN THE ENLIGHTENMENT
Authors: TERRALL MARY 
Published: August 2005

Mi Gyung Kim, Affinity, That Elusive Dream: A Genealogy of the Chemical Revolution (Cambridge, MA: MIT Press, 2003)Guiliano Pancaldi, Volta: Science and Culture in the Age of Enlightenment (Princeton, NJ: Princeton University Press, 2003)To challenge the presumed isolation of the scientific method from social concerns and forces, to question the inevitability of progress, to explore the ideological and polemical aspects of science—all these are by now goals commonly stated in historical studies of science. In the quest for these desiderata over the past twenty years or so, historians of science have in many cases distanced themselves from intellectual history in its idealist, disembodied form. However, in spite of salutary moves to analyze instruments, laboratory practices, visual representations, instituions and politics, a great deal of the raw material for the history of science remains textual, very often in the form of print. And, as the existence of this journal attests, intellectual history has retooled to take seriously the contexts for ideas and intellectual movements. At the present moment, when intellectual historians and historians of science are allied in the game of contextualizing our subjects, it is worth considering how current scholarship is working to define multi-layered contexts for scientific ideas and the texts in which they appear.
Effects of elevated O3and CO2concentrations on photosynthesis and stomatal conductance in Scots pine
Authors: KELLOMäKI S. , WANG K.‐Y. 
Published: August 2005

ABSTRACTNaturally regenerated Scots pines (Pinus sylvestrisL.), aged 28–30 years old, were grown in open‐top chambers and subjected insituto three ozone (O3) regimes, two concentrations of CO2, and a combination of O3and CO2treatments From 15 April to 15 September for two growing seasons (1994 and 1995). The gas exchanges of current‐year and 1‐year‐old shoots were measured, along with the nitrogen content of needles. In order to investigate the factors underlying modifications in photosynthesis, five parameters linked to photosynthetic performance and three to stomatal conductance were determined. Elevated O3concentrations led to a significant decline in the CO2compensation point (Г*), maximum RuP2‐saturated rate of carboxylation (Vcmax), maximum rate of electron transport (Jmax), maximum stomatal conductance (gsmax), and sensitivity of stomatal conductance to changes in leaf‐to‐air vapour pressure difference (∂gs/∂Dv) in both shoot‐age classes. However, the effect of elevated O3concentrations on the respiration rate in light (Rd) was dependent on shoot age. Elevated CO2(700 μmol mol−1) significantly decreasedJmaxandgsmaxbut increasedRdin 1‐year‐old shoots and the ∂gs/∂Dvin both shoot‐age classes. The interactive effects of O3and CO2on some key parameters (e.g.VcmaxandJmax) were significant. This may be closely related to regulation of the maximum stomatal conductance and stomatal sensitivity induced by elevated CO2. As a consequence, the injury induced by O3was reduced through decreased ozone uptake in 1‐year‐old shoots, but not in the current‐year shoots. Compared to ambient O3concentration, reduced O3concentrations (charcoal‐filtered air) did not lead to significant changes in any of the measured parameters. Compared to the control treatment, calculations showed that elevated O3concentrations decreased the apparent quantum yield by 15% and by 18%, and the maximum rate of photosynthesis by 21% and by 29% in the current‐year and 1‐year‐old shoots, respectively. Changes in the nitrogen content of needles resulting from the various treatments were associated with modifications in photosynthetic components.
Leaf senescence in a non‐yellowing mutant of Festuca pratensis: implications of the stay‐green mutation for photosynthesis, growth and nitrogen nutrition
Authors: HAUCK B. , GAY A. P. , MACDUFF J. , GRIFFITHS C. M. , THOMAS H. 
Published: August 2005

ABSTRACTMutation of the nuclear gene sid disables chlorophyll degradation during leaf senescence in the pasture grass Festuca pratensis. This study investigated the effect of the mutation on photosynthesis and on leaf and whole plant growth under a range of nitrogen regimes. When plants were cultivated in a static hydroponic system, the chlorophyll content of fourth leaves of the stay‐green mutant Bf993 remained virtually unchanged from full expansion to complete senescence, while tissue of the wild‐type (cv. Rossa) became completely yellow. The retention of chlorophyll in Bf993 was not associated with maintenance of photosynthetic activity as shown by rates of light‐saturated CO2 fixation and apparent quantum efficiency. Higher levels of total N in senescing leaves of Bf993 than in Rossa indicated reduced nitrogen remobilization in the mutant. When using a range of [NH4NO3], dry matter production and tillering Mere lower for Bf993 at all but the highest [NH4NO3, which was supra‐optimal for the wild type. In contrast to the static system, where fluctuations in N supply occurred, growth and [NO3−] uptake were similar in mutant and wild type when [NO3−] was continuously maintained by a flowing solution culture system. The results are discussed in relation to the role of N supply and the effect of the stay‐green mutation on N recycling.
Occupational allergy in laboratory workers caused by the African migratory grasshopper Locusta migratoria
Authors: Lopata A. L. , Fenemore B. , Jeebhay M. F. , Gäde G. , Potter P. C. 
Published: August 2005

Background:  Recent reports of fatal asthma cases associated with swarms of locusts affecting African countries have highlighted the importance of this insect in causing asthma morbidity and mortality. However, only limited information is available about the allergic health outcomes such as asthma and its determinants in exposed individuals. In this study, workers exposed to the African migratory locust Locusta migratoria were evaluated for allergic health outcomes as well as the nature of the offending allergens.Methods:  Ten scientists and technicians exposed to locusts in a laboratory were investigated for locust‐related allergy using questionnaires and immunological tests. The presence of allergy was determined by quantification of specific IgE and IgG to L. migratoria using the UniCAP® system and via skin‐prick testing (SPT). The allergens were characterized by Western blot and ImmunoCAP inhibition assays.Results:  Six of the 10 workers experienced symptoms ranging from urticaria and rhinoconjuctivitis to asthma. Seven individuals demonstrated sensitivity on SPT and five had specific IgE antibodies to L. migratoria. Significant cross‐reactivity was demonstrated for allergens in the locust faeces, body and wings but not to cockroach allergens. Novel allergens with molecular weights of approximately 70 kDa were identified in locust wings, which are distinctly different from other known allergen sources from locusts.Conclusion:  Exposure to L. migratoria allergens is a potential sensitizer in exposed individuals. Raised levels of locust‐specific IgE can be readily quantified. The wings of this insect species have been identified as a novel allergen source.
Bahia grass pollen specific IgE is common in seasonal rhinitis patients but has limited cross‐reactivity with Ryegrass
Authors: Davies J. M. , Bright M. L. , Rolland J. M. , O'Hehir R. E. 
Published: August 2005

Background:  Perennial Ryegrass is a major cause of rhinitis in spring and early summer. Bahia grass, Paspalum notatum, flowers late into summer and could account for allergic rhinitis at this time. We determined the frequency of serum immunoglobulin (Ig)E reactivity with Bahia grass in Ryegrass pollen allergic patients and investigated IgE cross‐reactivity between Bahia and Ryegrass.Methods:  Serum from 33 Ryegrass pollen allergic patients and 12 nonatopic donors were tested for IgE reactivity with Bahia and Ryegrass pollen extracts (PE) by enzyme‐linked immunosorbent assay (ELISA), western blotting and inhibition ELISA. Allergen‐specific antibodies from a pool of sera from allergic donors were affinity purified and tested for IgE cross‐reactivity.Results:  Seventy‐eight per cent of the sera had IgE reactivity with Bahia grass, but more weakly than with Ryegrass. Antibodies eluted from the major Ryegrass pollen allergens, Lol p 1 and Lol p 5, showed IgE reactivity with allergens of Ryegrass and Canary but not Bahia or Bermuda grasses. Timothy, Canary and Ryegrass inhibited IgE reactivity with Ryegrass and Bahia grass, whereas Bahia, Johnson and Bermuda grass did not inhibit IgE reactivity with Ryegrass.Conclusions:  The majority of Ryegrass allergic patients also showed serum IgE reactivity with Bahia grass PE. However, Bahia grass and Ryegrass had only limited IgE cross‐reactivity indicating that Bahia grass should be considered in diagnosis and treatment of patients with hay fever late in the grass pollen season.
Effect of budesonide and montelukast in asthmatic children exposed to relevant allergens
Authors: Peroni D. , Bodini A. , Miraglia Del Giudice M. , Loiacono A. , Baraldi E. , Boner A. L. , Piacentini G. 
Published: August 2005

Background: Montelukast has been shown to be effective in controlling the increase in exhaled NO in asthmatic children re‐exposed to house dust mite (HDM). This study compared the effect of low dose inhaled budesonide and oral montelukast in preventing the expected relapse of airway inflammation and reactivity in a group of 24 mild asthmatic children allergic to HDM after a brief period of exposure to relevant allergens.Methods: Lung function, bronchial hyperresponsiveness (BHR) to methacholine (PC20), fractional exhaled nitric oxide (FeNO) levels and sputum eosinophilia were evaluated.Results: Pulmonary function remained stable. The BHR was unchanged after exposure in the group treated with budesonide, whereas a significant increase (P = 0.028) was observed in the patients receiving montelukast. No significant difference was observed in FeNO levels after exposure to mite antigen in the two groups. In both the groups of asthmatic children we observed a significant increase in sputum eosinophil % after the exposure to mite antigen.Conclusions: The significant increase in BHR level observed in the group of children receiving montelukast suggests a more comprehensive effect as disease controller by inhaled steroids than by leukotriene antagonist in allergic asthmatic children re‐exposed to relevant allergens.
Analysis of exhaled leukotrienes in nonasthmatic adult patients with seasonal allergic rhinitis
Authors: Čáp P. , Pehal F. , Chládek J. , Malý M. 
Published: August 2005

Background:  Leukotrienes (LTs) are increased in exhaled breath condensate (EBC) in patients with asthma. So far no data have been reported about LT levels in nonasthmatic patients with seasonal allergic rhinitis (SAR). The aim of the study was to find out whether the LT levels in EBC were increased in the nonasthmatic adult patients with SAR both during and after the pollen season in comparison with healthy controls and to assess the changes of the LT levels after the pollen season.Methods:  Twenty‐nine nonasthmatic adult patients with SAR underwent measurement of exhaled LTs in the EBC during and after the pollen season. Leukotrienes B4, C4, D4 and E4 were analysed by a specific and sensitive gas chromatography/mass spectrometry (GC/MS) assay and compared with 50 healthy nonsmoking controls. Spirometry, skin prick tests and nonspecific IgE were evaluated.Results:  Leukotrienes concentrations (B4, E4 but not D4) were significantly increased in and after the pollen season in patients with SAR in comparison with healthy controls. In most of the samples, LT C4 was undetectable. The values of all exhaled LTs were significantly decreased after the pollen season compared with the seasonal baseline: LTB4 (P = 0.023), LTD4 (P = 0.020), LTE4 (P = 0.047).Conclusions:  Levels of exhaled LTB4 and LTE4 were higher in SAR patients than in healthy controls and decreased after the pollen season as compared with levels in season. The SAR patients with the highest in season LT levels had also the post‐season levels elevated and this may be an early marker of inflammatory process in the lower airways despite the absence of clinical symptoms of asthma.