bluuebunny/crossref_metadata_2025_split huggingface dataset:
Is the changing precipitation regime of Manchester, United Kingdom, driven by the development of urban areas?
Authors: Russell Andrew , Hughes Meghan 
Published: March 2011

AbstractPrecipitation measurements made at three weather stations and one composite record from the Manchester region and the Isle of Man have been analysed over the period 1899–2008. Large positive trends over the last 40 years were identified for the three records within 50 km of Manchester whilst the Isle of Man measurements revealed no such trend. The recent increase in rainfall at the urban or urban‐influenced sites was significantly and negatively correlated with NOx emissions recorded in Manchester whilst local temperature and atmospheric circulation indices appeared to be largely unrelated. Sea surface temperature in the precipitation source region was also significantly related to annual precipitation levels. Further evidence for an urban influence was investigated but an analysis of back trajectories (BTs) showed only a slight increase in rainfall on the days where the trajectories tracked back past an urban centre. However, the discovery of a weekly cycle in the precipitation increase suggests that an urban influence should not be ruled out. The complicated factors driving this distinctive rainfall trend require further investigation so that water resources and flood impacts can be managed more effectively in the future. Copyright © 2011 Royal Meteorological Society
Distribution of phosphorus in size fractions of sandy soils with different fertilization histories
Authors: Geisseler Daniel , Linsler Deborah , Piegholdt Christiane , Andruschkewitsch Rouven , Raupp Joachim , Ludwig Bernard 
Published: March 2011

AbstractA major challenge in sustainable crop management is to ensure adequate P supply for crops, while minimizing losses of P that could negatively impact water quality. The objective of the present study was to investigate the effects of long‐term applications of different levels of mineral fertilizers and farmyard manure on (1) the availability of P, (2) the relationship between soil C, N, and P, and (3) the distribution of inorganic and organic P in size fractions obtained by wet sieving. Soil samples were taken from the top 20 cm of a long‐term (29 y) fertilization trial on a sandy Cambisol near Darmstadt, SW Germany. Plant‐available P, determined with the CAL method, was little affected by fertilization treatment (p < 0.05) and was low to optimal. The concentration of inorganic and organic P extracted with a NaOH‐EDTA solution (PNaOH‐EDTA) averaged about 350 mg (kg dry soil)–1, with 42% being in the organic form (Po). Manure application tended to increase soil C, N, and Po concentrations by 8%, 9%, and 5.6%, respectively. Across all treatments, the C : N : Po ratio was 100 : 9.5 : 2 and was not significantly affected by the fertilization treatments. Aggregate formation was weak due to the low clay and organic‐matter content of the soil, and the fractions > 53 μm consisted predominantly of sand grains. The different fertilization treatments had little effect on the distribution of size fractions and their C, N, and P contents. In the fractions > 53 μm, PNaOH‐EDTA ranged between 200 and 300 mg kg–1, while it reached 1260 mg kg–1 in the fraction < 53 μm. Less than one third of PNaOH‐EDTA was present as Po in the fractions > 53 μm, while Po accounted for 70% of PNaOH‐EDTA in the smallest fraction (< 53 μm). Therefore, 16% and 28% of PNaOH‐EDTA and Po, respectively, were associated with the smallest fraction, even though this fraction accounted for < 5% of the soil mass. Therefore, runoff may cause higher P losses than the soil P content suggests in this sandy soil with a weak aggregate formation. Overall, the results indicate that manure and mineral fertilizer had similar effects on soil P fractions.
Origin of spectral interferences in femtosecond stimulated Raman microscopy
Authors: Ploetz E. , Marx B. , Gilch P. 
Published: March 2011

AbstractIn femtosecond stimulated Raman microscopy (FSRM), a spectrally narrow (Raman pump) pulse and a broad (Raman probe) laser pulse are employed to generate the Raman spectra of microscopic objects. The resulting spectra exhibit, in addition to the Raman bands, spectral modulations of comparable amplitude. Here a model is devised that attributes these modulations to a four‐wave mixing (FWM) process. Two light fields of the probe pulse and one field of the pump pulse serve as input fields. The resulting FWM field experiences a heterodyne amplification by the probe field. Simulations based on this model reproduce the appearance of the spectral modulations. Furthermore, the amplitude of the modulations exhibits dependences on the energies of pump and probe pulses as well as on the nonlinear refractive index n2, which are in line with the model. Copyright © 2011 John Wiley & Sons, Ltd.
Separation of acetins by counter‐current chromatography
Authors: Meireles Bruno Amaral , Pinto Shaft Corrêa , Pereira Vera Lúcia Patrocinio , Leitão Gilda Guimarães 
Published: March 2011

AbstractIn this work we report the purification of a crude acetin mixture into mono‐, di‐ and triacetin by countercurrent chromatography. The process was initially tested on a small, semi‐preparative scale (0.5 g) to determine its efficiency. The process was then scaled up to accommodate 2.5 g of crude reaction products containing a mixture of the acetins. The solvent system ethyl acetate/n‐butanol/water 1:0.2:1 was used in all separation procedures. Mono‐, di‐ and triacetins were separated similarly in the semi‐preparative and preparative runs.
Continuous‐flow separation of nanoparticles by electrostatic sieving at a micro‐nanofluidic interface
Authors: Regtmeier Jan , Käsewieter Jörg , Everwand Martina , Anselmetti Dario 
Published: March 2011

AbstractContinuous‐flow separation of nanoparticles (NPs) (15 and 39 nm) is demonstrated based on electrostatic sieving at a micro‐nanofluidic interface. The interface is realized in a poly(dimethylsiloxane) device with a nanoslit of 525 nm laterally spanning the microfluidic channel (aspect ratio of 540:1). Within this nanoslit, the Debye layers overlap and generate an electrostatic sieve. This was exploited to selectively deflect and sort NPs with a sorting purity of up to 97%. Because of the continuous‐flow operation, the sample is continuously fed into the device, immediately separated, and the parameters can be adapted in real time. For bioanalytical purposes, we also demonstrate the deflection of proteins (longest axis 6.8 nm). The continuous operation mode and the general applicability of this separation concept make this method a valuable addition to the current Lab‐on‐a‐Chip devices for continuous sorting of NPs and macromolecules.
More than the loss of a parent: Potentially traumatic events among orphaned and abandoned children
Authors: Whetten Kathryn , Ostermann Jan , Whetten Rachel , O'Donnell Karen , Thielman Nathan ,   The Positive Outcomes for Orphans Research Team
Published: March 2011

AbstractThis study examines rates of potentially traumatic events and associated anxiety and emotional/behavioral difficulties among 1,258 orphaned and abandoned children in 5 low‐ and middle‐income countries. The study quantifies the types of events the children experienced and demonstrates that anxiety and emotional/behavioral difficulties increase with additional exposure. As policies for orphaned and abandoned children are being implemented, this study helps policy makers and care providers recognize that (a) children and caregivers are willing to report experiences of potentially traumatic events, (b) those who report such events are at higher risk for experiencing additional events, (c) resulting symptomatology indicates a need for appropriate mental health services, and (d) boys are as vulnerable as girls, indicating an equal need for protection.
Facile Synthesis of Hierarchical Conducting Polymer Nanotubes Derived from Nanofibers and Their Application for Controlled Drug Release
Authors: Han Jie , Wang Lu , Guo Rong 
Published: March 2011

AbstractHollowing of inorganic nano/micromaterials can be realized by well‐known Ostwald ripening and Kirkendall processes. However, hollowing of organic polymer without sacrificial templates is seldom seen. Herein, we demonstrate for the first time that conducting polymer nanofibers can be transformed into nanotubes by a simple, effective, and controllable swelling–evaporation strategy. By controlling swelling degree, surface‐patterned poly(o‐toluidine) (POT) nanofibers, and nanotubes with controllable inner diameter can be fabricated. Novel characteristics of such nanotubes, such as patterned surfaces and sealed tips, will endow them with enhanced properties when applied in fields as controlled drug delivery, noble metal nanocatalysts supporter, and adsorbent for heavy‐metal ions. magnified image
Mechanical behaviour of aluminum screws Part 2 – Cyclic behaviour
Authors: Arz U. , Weber J. O. , Marx T. , Berger C. 
Published: March 2011

AbstractDer vorliegende Beitrag ist der zweite Teil zur Tragfähigkeit von Aluminiumschrauben. Während sich der erste Teil der Tragfähigkeit unter statischer Beanspruchung widmet, wird in diesem Teil das zyklische Verhalten betrachtet. Es wird eine Übersicht über die zyklische Tragfähigkeit und deren Beeinflussung von hochfesten Aluminiumschrauben aus den Knetwerkstoffen EN AW 6013, EN AW 6056 und EN AW 7075 gegeben. Vereinzelt finden sich Hinweise auf die Legierung EN AW 6082.
Investigations of glass sealing and reactive air brazing materials for joining high temperature solid oxide fuel cells by dilatometric examinations
Authors: Reichle M.S. , Koppitz T. , Federmann D. , Reisgen U. 
Published: March 2011

AbstractEine Hochtemperaturbrennstoffzelle (solid oxide fuel cell = SOFC) hat zwar ein sehr einfaches Funktionsprinzip, jedoch erfordern die sehr unterschiedlichen Materialien der Einzelkomponenten hochentwickelte thermische Fügeverfahren, um sie funktionsgerecht miteinander zu verbinden. Für die SOFC existieren zwei Optionen einer möglichen Anwendung, erstens als dezentrale Hauskraftwerke (stationäre SOFC), zweitens als Energiewandler für Kraftfahrzeuge (mobile SOFC). Es haben sich daher im Forschungszentrum Jülich zwei sehr verschiedene Konstruktionstypen etabliert, für die auch die Entwicklung unterschiedlicher Verfahren zum Fügen der Einzelkomponenten erforderlich wurde. Beim stationären Design besteht der Hauptfügeprozess in dem elektrisch isolierenden Verbinden einzelner Stahlplatten durch ein Glaslot zu einem SOFC‐Stapel. Beim mobilen Design besteht der SOFC‐Stapel aus einzelnen dünnen Stahlkassetten. Bei den Kassetten wird deren Fensterblech aus ferritischem Chromstahl mit der keramischen Schicht des Zirkonoxidfeststoffelektrolyten durch ein metallisches Lot verlötet. Es handelt sich bei diesem Lot um ein Silberbasislot mit nur geringen benetzungsbegünstigenden Zusätzen von Kupferoxid und Titanhydrid. Entscheidend für beide Lötprozesse ist ihre Anwendbarkeit in normaler Atmosphäre (Luft), also unter oxidativen Bedingungen. Um die SOFC zur Marktreife auf dem Energiesektor zu entwickeln, dauern die F&E‐Arbeiten zur Wirkungsgradsteigerung und zur Langzeitbetriebsstabilität an. Auch die beiden Lötverfahren sind noch nicht als normale Standardprozesse zu betrachten, sondern erfordern ebenso permanente Weiterentwicklungen, hier im Hinblick auf Reproduzierbarkeit, Beständigkeit und Festigkeit der Lötverbunde. Auf der Suche nach geeigneten schnellen Ersatzmethoden, um die Fügeeigenschaften der Lotmaterialien genauer studieren und messtechnisch erfassen zu können, ohne den Bau aufwendiger komplexer SOFC‐Stacks betreiben zu müssen, setzt die Arbeitsgruppe Sonderfügetechnik im Forschungszentrum Jülich speziell abgewandte dilatometrische Messverfahren ein. Mit einem sog. Absenkdilatometer werden die Schwindungsprozesse der Glaslotfugen nachgestellt und im μm‐Bereich gemessen. Dies ermöglicht, die für Dichtheit und Kontaktierung entscheidende Glaslotmenge und die Prozessparameter vorherzubestimmen. Mit einem vertikalen Dilatometer erfolgen Untersuchungen des Schmelzverhaltens der reaktiven Silberlote im Hinblick auf Schmelzpunktverschiebung, Zähigkeit und Porenanteil und in Abhängigkeit von der Prozessatmosphäre und von einem metallischen Additiv (Aluminium).
Blind randomized controlled study of the efficacy of cognitive training in Parkinson's disease
Authors: París Anna Prats , Saleta Heidi Guerra , de la Cruz Crespo Maraver Maria , Silvestre Emmanuel , Freixa Maite Garolera , Torrellas Cristina Petit , Pont Silvia Alonso , Nadal Marc Fabra , Garcia Sheila Alcaine , Bartolomé Maria Victoria Perea , Fernández Valentina Ladera , Bayés Àngels Rusiñol 
Published: March 2011

AbstractThe aim of this study was to analyze the efficacy of a cognitive training program on cognitive performance and quality of life in nondemented Parkinson's disease patients. Participants who met UK Brain Bank diagnosis criteria for Parkinson's disease, with I–III Hoehn & Yahr, aged 50–80, and nondemented (Mini‐Mental State Examination ≥ 23) were recruited. Patient's cognitive performance and functional and quality‐of‐life measures were assessed with standardized neuropsychological tests and scales at baseline and after 4 weeks. Subjects were randomly and blindly allocated by age and premorbid intelligence (Vocabulary, Wechsler Adult Intelligence Scale‐III) into 2 groups: an experimental group and a control group. The experimental group received 4 weeks of 3 weekly 45‐minute sessions using multimedia software and paper‐and‐pencil cognitive exercises, and the control group received speech therapy. A total of 28 patients were analyzed. Compared with the control group participants (n = 12), the experimental group participants (n = 16) demonstrated improved performance in tests of attention, information processing speed, memory, visuospatial and visuoconstructive abilities, semantic verbal fluency, and executive functions. There were no observable benefits in self‐reported quality of life or cognitive difficulties in activities of daily living. We concluded that intensive cognitive training may be a useful tool in the management of cognitive functions in Parkinson's disease. © 2011 Movement Disorder Society
Ventricular dilatation and brain atrophy in patients with Parkinson's disease with incipient dementia
Authors: Camicioli Richard , Sabino Jennifer , Gee Myrlene , Bouchard Thomas , Fisher Nancy , Hanstock Chris , Emery Derek , Martin W.R. Wayne 
Published: March 2011

AbstractAge‐related ventricular enlargement is accelerated in Alzheimer's disease, but its relationship to cognitive decline in Parkinson's disease is less clear, even though dementia is common in Parkinson's disease. Our goals were to determine if greater enlargement of the ventricles and gray or white matter atrophy occurred in Parkinson's disease patients developing cognitive decline. Older nondemented patients with Parkinson's disease (33) and age‐ and sex‐matched controls (39) were recruited and prospectively assessed for the development of significant cognitive decline over 36 months. Magnetic resonance imaging was obtained every 18 months, and ventricular volume and total brain gray and white matter volumes were measured using reliable segmentation of T1‐weighted volumetric scans. Subjects with incidental intracranial abnormalities, an atypical course, and stroke as well as dropouts were excluded from a cohort of 52 patients and 50 controls. Among 33 patients and 39 controls, 10 patients and 3 controls developed significant cognitive impairment or dementia. Ventricular change and Parkinson's disease status were significantly associated with dementia. Ventricular change was significantly correlated with change in Mini‐Mental Status Examination in the Parkinson's disease with dementia group (r = 0.87, P = .001). Gray matter atrophy was greater in Parkinson's disease with dementia, with similar change over time in both Parkinson's disease and Parkinson's disease with dementia. White matter volumes were not significantly different between Parkinson's disease and Parkinson's disease with dementia; however, the decrease over time might be greater in Parkinson's disease with dementia. Ventricular dilatation occurs early in the course of significant cognitive decline in patients with Parkinson's disease, possibly reflecting both cortical gray and white matter loss. © 2011 Movement Disorder Society
Chip design of an UWB and high gain on‐chip transformer receiver front‐end
Authors: Huang Jhin‐Fang , Shie Pei‐Jiuan , Liu Ron‐Yi 
Published: March 2011

AbstractAn ultra‐wideband receiver front‐end operating in 3.1–8.0 GHz frequency range is presented. The proposed front‐end consists of on‐chip transformer low‐noise amplifier, passive balun, double‐balanced mixer, and is fabricated in a TSMC 0.18 μm CMOS process with 1.8 V supply voltage. Measured results show that maximum conversion gain of 30.32 dB, noise figure less than 5.9 dB, input return loss (S11) smaller than −15.3 dB, input‐referred third‐order intercept point of −21.4 dBm, 1 dB compression point (P1 dB) of −30 dBm over the whole frequency range of interest are achieved. In addition, isolations of LO to RF and LO to IF are less than −57 dB and −27.8 dB, respectively, chip area including pads is only 0.985 mm2 and power dissipation is 36.88 mW. The realized front‐end achieves the smallest chip area and the best merit of figure compared with previously reported front‐ends. © 2011 Wiley Periodicals, Inc. Microwave Opt Technol Lett 53:1422–1427, 2011; View this article online at wileyonlinelibrary.com. DOI 10.1002/mop.25956
Low profile dual‐feed Planar Inverted‐F Antenna for wireless LAN applications
Authors: Chattha Hassan Tariq , Huang Yi 
Published: March 2011

AbstractThis letter presents a new low profile dual‐feed Planar Inverted‐F Antenna (PIFA) suitable for wireless LAN applications. Pattern diversity is exploited using one common radiating plate and two isolated feeding ports. The isolation is successfully achieved mainly by modifying the ground plane under the radiating plate and producing an antiresonance between the ports. Thus, this single PIFA antenna can act as two separate antennas for diversity and MIMO applications with reduced space and cost. Simulated and measured results are obtained to verify the conclusion. © 2011 Wiley Periodicals, Inc. Microwave Opt Technol Lett 53:1382–1386, 2011; View this article online at wileyonlinelibrary.com. DOI 10.1002/mop.25958
Printed monopole antenna on a thin substrate for UWB applications
Authors: Yoon Cheol , Kim Woo‐Su , Kang Suk‐Youb , Lee Hwa‐Choon , Park Hyo‐Dal 
Published: March 2011

AbstractA compact and simple design of a printed monopole antenna on a thin substrate for ultra‐wideband applications is presented. The antenna size is 30 × 36 × 0.4 mm3 and operates over an extremely wide band of 2.82–13.60 GHz. The proposed design consists of a coplanar radiator and a ground plane on a thin FR‐4 substrate. The advantages of the proposed antenna are its low cost, compact size, thin substrate, and simple design. The measured impedance bandwidth defined by voltage standing wave ratio (VSWR) ≤2 of 10.78 GHz (2.82–13.60 GHz) is obtained. Moreover, omnidirectional radiation patterns with appreciable gain across the operating band can be obtained. © 2011 Wiley Periodicals, Inc. Microwave Opt Technol Lett 53:1262–1264, 2011; View this article online at wileyonlinelibrary.com. DOI 10.1002/mop.25964
A novel planar triple‐mode bandpass filter with slits perturbation
Authors: Guo L. , Yu Z.‐Y. 
Published: March 2011

AbstractA novel planar microstrip triple‐mode bandpass filter is proposed by introducing slits into λ/2 traditional microstrip resonator in this article.The slits cannot only perturb the traditional resonator for the multimode operation but also generate transmission zero point at stopband for the stopband control. By using different kinds of slits, different kinds of responses triple‐mode bandpass filter can be realized. For method validation, a filter operating at 2.45 GHz is fabricated and measured. Both the simulated results and the measured results are presented. © 2011 Wiley Periodicals, Inc. Microwave Opt Technol Lett 53:1260–1262, 2011; View this article online at wileyonlinelibrary.com. DOI 10.1002/mop.25965
Small‐signal lumped‐element modeling of P‐I‐N photodiode
Authors: Miao Ang 
Published: March 2011

AbstractA small‐signal lumped‐element modeling technique for P‐I‐N photodiodes is presented.The model is extracted by fitting model's components with the accurately measured S parameters using the genetic algorithm. Experimental results indicate the extracted model is well matched to the measured data in the frequency range from 130 MHz to 20 GHz. © 2011 Wiley Periodicals, Inc. Microwave Opt Technol Lett 53:1416–1419, 2011; View this article online at wileyonlinelibrary.com. DOI 10.1002/mop.25971
Enhancing patch antenna bandwidth by means of uniplanar EBG‐AMC
Authors: de Cos M. Elena , Álvarez Yuri , Las‐Heras Fernando 
Published: March 2011

AbstractThe design of a bandwidth‐enhanced uniplanar MPA using EBG‐AMC is presented.The designed structure with neither via holes nor multilayer substrates yields bandwidth enhancement still with useful radiation pattern values in its band. Two prototypes, a MPA and a PA with uniplanar EBG‐AMC (PA_U‐EBG‐AMC), are manufactured and characterized based on return losses and radiation pattern. © 2011 Wiley Periodicals, Inc. Microwave Opt Technol Lett 53:1372–1377, 2011; View this article online at wileyonlinelibrary.com. DOI 10.1002/mop.25974
A Ka‐band quasi‐optical power‐divider basing on Talbot Effect of phase grating
Authors: Li Guang , Huang Jian , Pei Naichang 
Published: March 2011

AbstractA new design of quasi‐optical (QO) power divider at millimeter wave band is presented in this article. The Talbot Effect of periodical phase grating is applied to realize power dividing with high efficiency. A novel periodic phase profile was adopted to make a linear region of zero diffraction filed. Then a closed metallic cavity can be used to screen the power divider with the wall placed in this region without disturbance to field distribution and efficiency degrading, which improves electromagnetic compatibility of QO power combining system greatly. The Scalar Diffraction theory is applied to analyze the “Talbot Pattern” and then generic algorithm is used to optimize the phase profile. A 1 × 18 divider was designed and tested at 37.5GHz. The efficiency is tested to be 80.8%, which is well agreed with the simulated value of 88.7%. Since efficiency of QO power divider/combiner is essentially independent of the number of combining elements and the inter‐element spacing, this technology can be extended to power dividing or combining of large number of ways up to THz band. © 2011 Wiley Periodicals, Inc. Microwave Opt Technol Lett 53:1331–1336, 2011; View this article online at wileyonlinelibrary.com. DOI 10.1002/mop.25975
An empirical I‐V nonlinear model suitable for GaN FET class F PA design
Authors: García‐Osorio A. , Loo‐Yau J. R. , Reynoso‐Hernández J. A. , Ortega‐C. Susana , del Valle‐Padilla J. L. 
Published: March 2011

AbstractThis article presents an improved nonlinear IDS(VGS, VDS) model useful for modeling the experimental pulsed I‐V measurement data of GaN FETs operated at large drain‐source voltages. This improved IDS(VGS, VDS) model is based on the Chalmers model. The main features of the improved nonlinear IDS(VGS, VDS) model are the two analytical expressions that are incorporated to model the output conductance and the saturation voltage. The new model only requires 13 parameters easily determined from experimental pulsed I‐V data. Comparison between simulated and measured data of an inverse class F PA designed with a commercial GaN FET at 1.5 GHz demonstrate that the proposed model is suitable for microwave circuit design based on GaN transistors. © 2011 Wiley Periodicals, Inc. Microwave Opt Technol Lett 53:1256–1259, 2011; View this article online at wileyonlinelibrary.com. DOI 10.1002/mop.25980