bluuebunny/crossref_metadata_2025 huggingface dataset:
FT‐Raman spectroscopy—a rapid and reliable quantification protocol for the determination of natural indigo dye in Polygonum tinctorium
Authors: Fiedler Andrea , Baranska Malgorzata , Schulz Hartwig
Published: June 2010

In the recent years, Raman and IR spectroscopies have attracted increasing attention as fast, non‐invasive and widely applicable alternative analytical approaches for a variety of materials. Vibrational spectroscopy has been used in the analysis of herbal products, dyes and sensitive art objects, besides complex and aqueous biomaterials such as biopolymers or mammalian tissue. Compared to conventional analytical methods based on high‐performance liquid chromatography (HPLC) or gas chromatography, which often involves extensive and time‐consuming sample preparation, Raman or IR spectroscopy can avoid these procedures. The present work introduces a fast and reliable quantification method for the determination of naturally occurring indigo dye in dyer's knotweed (Polygonum tinctorium) based on Fourier transform (FT) Raman spectroscopy. The results were validated by HPLC‐UV, and the merits and drawbacks of the present method are elaborated. Besides the qualitative aspects of signal assignment and comparison to appropriate attenuated total reflectance Fourier transform infrared (ATR‐FT‐IR) measurements, the Raman spectrum of dihydro indigo, an important intermediate in the indigo dying process, is presented for the first time and discussed with regard to its spectroscopic behaviour. Copyright © 2010 John Wiley & Sons, Ltd.
Raman and IR studies of TaWO5.5, ASbWO6 (A = K, Rb, Cs, Tl), and ASbWO6·H2O (A = H, NH4, Li, Na) pyrochlore oxides
Authors: Ma̧czka M. , Knyazev A. V. , Kuznetsova N. Yu. , Ptak M. , Macalik L.
Published: June 2010

Raman and infrared (IR) spectra of defect pyrochlores TaWO5.5, NH4SbWO6·H2O, HSbWO6·H2O, LiSbWO6·H2O, NaSbWO6·H2O, KSbWO6, RbSbWO6, CsSbWO6, and TlSbWO6 were measured. The obtained spectra are discussed using the factor group approach for the cubic Fd‐3m space group, and assignment of bands to respective motions of atoms is proposed. Our results show that the phonon properties of the pyrochlores are strongly affected by disorder, and therefore Raman and IR spectroscopies are very useful tools in studying disorder in this family of compounds. In particular, our studies have shown that in these ionic conductors disorder at sites occupied by NH$_{4}^{+}$, H+, or alkali‐metal ions decreases with increasing size and mass of these ions. Copyright © 2010 John Wiley & Sons, Ltd.
Meeting the 12 lymph node (LN) benchmark in colon cancer
Authors: Rajput A. , Romanus D. , Weiser M.R. , Ter Veer A. , Niland J. , Wilson J. , Skibber J.M. , Wong Y.‐N. , Benson A. , Earle C.C. , Schrag D.
Published: June 2010

Background

Examining ≥12 LN in colon cancer has been suggested as a quality metric. The purpose of this study was to determine whether the 12 LN benchmark is achieved at NCCN centers compared to a US population‐based sample.

Methods

Patients with stage I–III disease resected at NCCN centers were identified from a prospective database (n = 718) and were compared to 12,845 stage I–III patients diagnosed in a SEER region. Age, gender, location, stage, number of positive nodes were compared for NCCN and SEER data in regards to number of nodes evaluated. Multivariate logistic regression models were developed to identify factors associated with evaluating 12 LNs.

Results

92% of NCCN and 58% of SEER patients had ≥12 LN evaluated. For patients treated at NCCN centers, factors associated with not meeting the 12 LN target were left‐sided tumors, stage I disease and BMI >30.

Conclusions

≥12 LN are almost always evaluated in NCCN patients. In contrast, this target is achieved in 58% of SEER patients. With longer follow‐up of the NCCN cohort we will be able to link this quality metric to patterns of recurrence and survival and thereby better understand whether increasing the number of nodes evaluated is a priority for cancer control. J. Surg. Oncol. 2010;102:3–9. © 2010 Wiley‐Liss, Inc.
Rate coefficients for the reactions CH3 + Br2 (224–358 K), CH3CO + Br2 (228 and 298 K), and Cl + Br2 (228 and 298 K)
Authors: Khamaganov V. , Crowley J. N.
Published: June 2010

Rate coefficients for the reactions of CH3 + Br2 (k2), CH3CO + Br2 (k3), and Cl + Br2 (k5) were measured using the laser‐pulsed photolysis method combined with detection of the product Br atoms using resonance fluorescence. For the reactions involving organic radicals, the rate coefficients were observed to increase with decreasing temperature and within the temperature range explored, were adequately described by Arrhenius‐like expressions: k2 (224–358 K) = 1.83 × 10−11 exp(252/T) and k3 (228–298 K) = 2.92 × 10−11 exp(361/T) cm3 molecule−1 s−1. The total, temperature‐independent uncertainty for each reaction (including possible systematic errors in Br2 concentration measurement) was estimated as ∼7% for k2 and 10% for k3. Accurate data on k5 was obtained at 298 K, with a value of 1.88 × 10−10 cm3 molecule−1 s−1 obtained (with an associated error of 6%). A limited data set at 228 K suggests that k5 is, within experimental uncertainty, independent of temperature. © 2010 Wiley Periodicals, Inc. Int J Chem Kinet 42: 575–585, 2010
Lipid nutrition and eye health
Authors: Bretillon Lionel , Acar Niyazi , Berdeaux Olivier , Bron Alain , Creuzot‐Garcher Catherine
Published: June 2010

According to demographic forecasts, the elderly population will represent a growing part of the developed societies in the near future. Eye diseases are the second most prevalent pathologies after the age of 65 years. Age‐related macular degeneration (AMD) is the leading cause of irreversible vision loss in western countries. The number of people suffering from ocular pathologies is expected to increase sharply in the near future, becoming a socio‐economic burden. Recent data indicate that lipid nutrients may represent new tools in the prevention of eye diseases, and especially AMD.
Force‐Free Patterning of Polyelectrolyte Multilayers under Solvent Assistance
Authors: Han Lulu , Zhou Jing , Gong Xiao , Yang Jie , Gao Changyou
Published: June 2010

Physical patterns were created on hydrated PSS/PDADMAC multilayers without using external force. A typical process was to put a PDMS stamp onto the wet and swollen multilayers, which were then put into an oven and maintained for a period of time to micromold the multilayers. The influence of molding temperature and time, multilayer thickness, solvent quality, and multilayer compositions on pattern formation were elucidated. Evolution of the patterns from double lines, double strips, and meniscus‐shaped ridges to high ridges was observed under all conditions, revealing that this is a universal principle for this process. Finally, patterns on PAA/PAH and PSS/PAH multilayers were also prepared at the optimal conditions, highlighting its wide generality on the multilayer patterning.

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A Serre‐Swan Theorem for Bundles of Topological Modules
Authors: Papatriantafillou Maria H.
Published: June 2010

Let R be a unital topological ring whose set of invertible elements is open and inversion is continuous, and let X be a compact Hausdorff space admitting continuous R‐valued partitions of unity. Considering bundles over X of fibre type a projective finitely generated R‐module, we prove a Serre‐Swan type theorem: namely, the category of these bundles is equivalent to the category of projective finitely generated modules over the ring of continuous R‐valued functions on X.
Limited Sets in C(K)‐Spaces and Examples Concerning the Gelfand‐Phillips‐Property
Authors: Schlumprecht Thomas
Published: June 2010

In this paper we give criteria for limitedness in C(K)‐spaces and discuss the Gelfand‐Phillips‐property. We show that the Gelfand‐Phillips‐property is not a three‐space‐property, that l1 ⊄ X does not imply the Gelfand‐Phillips‐property of X and that the Gelfand‐Phillips‐property of a space X does not imply that the dual unit ball contains a w*‐sequentially precompact subset which norms X up to a constant.
Certain Norm Related Quantities of Unbounded Linear Operators
Authors: Labuschagne L. E.
Published: June 2010

Certain norm related functions of linear operators are considered in the very general setting of not necessarily continuous linear operators in normed spaces. These are shown to be closely related to the theory of precompact, strictly cosingular and a class of Φ− type operators in addition to having applications to perturbation theory. We also obtain some basic continuity and precompactness properties of linear operators in normed spaces which are expressed in terms of the functions under consideration.
A Remark on Hamiltonian Cycles
Authors: Vu‐Dinh‐Hoa
Published: June 2010

Let G be an undirected and simple graph on n vertices. Let ω, α and χ denote the number of components, the independence number and the connectivity number of G. G is called a 1‐tough graph if ω(G – S) ⩽ |S| for any subset S of V(G) such that ω(G − S) > 1. Let

σ2 = min {d(v) + d(w)|v and w are nonadjacent}.

Note that the difference α ‐ χ in 1‐tough graph may be made arbitrary large. In this paper we prove that any 1‐tough graph with σ2 > n + χ ‐ α is hamiltonian.
Non‐Zero Space Charge Approximation of Thyristors
Authors: Kern Marietta
Published: June 2010

The subject of this paper is the time‐independent one‐dimensional version of the van Roosbroeck system. We study thyristor structures and show the existence of solutions. Instead of the zero space charge approximation we study the full problem and prove a non‐blow‐up result with respect to the current J.
Some Observations on the Integrated Cauchy Functional Equation
Authors: Shanbhag D. N. , Radhakrishna Rao C.
Published: June 2010

In this paper, some new observations concerning the problem of solving two or more integral equations of the type in Ramachandran, Gu and Lau (1988) and Rao and Shanbhag (1989b) are made by reducing it to the one of solving the integral equation of the type in Davies and Shanbhag (1987). Some applications of the results on integral equations are also given.
Closedness of the Set of Extreme Points in Orlicz Spaces
Authors: Suarez‐Granero Antonio , Wisła Marek
Published: June 2010

The aim of the paper is to give necessary and sufficient conditions under which the set of extreme points of the unit ball of an Orlicz space Lϕ(μ), equipped with the Luxemburg norm, is closed. Using that description a theorem is given saying when the notions “extremal” and “nice”, for a linear bounded compact operator from Lϕ(μ) into C(Z), coincide.
Structural Properties of Planar Maps with the Minimal Degree 5
Authors: Borodin Oleg
Published: June 2010

We improve some old results concerning the numbers of such edges and faces in planar graphs having minimal degree 5 which are incident only to vertices of minor degrees.
Representation of Permutation Groups by Coloured Graphs
Authors: Baumann Ulrike
Published: June 2010

The topic of this paper is representing permutation groups by connected graphs with proper edge colourings. Every connected graph G with a proper edge colouring ϕ determines a group Ac(G, ϕ) of graph automorphisms which preserve the colours of the edges. We characterize permutation groups being full groups of colour preserving automorphisms for some kinds of proper edge colourings.
Measure Valued Solutions for Non‐Newtonian Compressible Isothermal Monopolar Fluids in a Finite Channel with Nonzero Input and Output
Authors: Matušů‐Nečasová Š.
Published: June 2010

The global existence of measure valued solutions of initial boundary value problems in a bounded domain with nonzero input and output in a finite channel for the systems of partial differential equations for viscous non‐Newtonian isothermal compressible monopolar fluids and the global existence of a weak solution for multipolar fluids is proved.
False Hyperelliptic Surfaces with Section
Authors: Nara Yoshifumi Takeda
Published: June 2010

Let X be a nonsingular relatively minimal projective surface over an algebraically closed field of characteristic p > 0. We call X a false hyperelliptic surface if X satisfies the following conditions: (1) c2(X) = 0, c1(X)2 = 0, dim Alb (X) = 1, and (2) All fibres of the Albanese mapping of X are rational curves with only one cusp of type xpv + yn = 0. In this article, we consider a false hyperelliptic surface whose Albanese mapping has a cross‐section. We prove that every false hyperellyptic surface with section arises from an elliptic ruled surface and that every false hyperelliptic surface has an elliptic fibration with multiple fibre. Moreover, we construct an example of false hyperelliptic surface with section, whose elliptic fibration has a multiple fibre of supersingular elliptic curve of multiplicity pv (v > 1).
Riemannian Metrics with the Prescribed Curvature Tensor and all Its Covariant Derivatives at One Point
Authors: Kowalski Oldřich , Belger Martin
Published: June 2010

On an n‐dimensional vector space, equipped with a scalar product, we prescribe (0, 4) ‐, (0, 5)‐, … type tensors R(0), R(1), …, satisfying the well‐known conditions for a curvature tensor and its derivatives and furthermore certain inequalities for the absolute values of the components of R(k). Then there is an analytic Riemannian metric g on an open ball of the Cartesian space Rn[u1, …, un] for which u1, …, un are normal coordinates and (▽(k)R)0 = R(k) (k = 0, 1, 2, …) hold under an identification of the tangent space T0Rn at the origin with the vector space; ▽(k)R denote the curvature tensor and its covariant derivatives with respect to the Levi‐Civita connection ▽ of g, respectively.
The Boundedness of Pseudodifferential Operators on Modulation Spaces
Authors: Tachizawa Kazuya
Published: June 2010

We give a characterization of d‐dimensional modulation spaces with moderate weights by means of the d‐dimensional Wilson basis. As an application we prove that pseudodifferential operators with generalized Weyl symbols are bounded on these modulation spaces.
On Hardy‐Bessel Potential Spaces Over the 2‐Series Field
Authors: Tateoka Jun
Published: June 2010

The purpose of this paper is to present characterizations of the inhomogeneous Hardy‐Bessel potential spaces Fpα (K) over the 2‐series field K defined by Littlewood‐Paley type function, magnified image where Δ0(x) = 1(|x|≥1), = 0(other), Δj(x) = 2j ≥, = 0(other) (j ≥ 1). These characterizations are given by difference of functions, ball means of difference and atoms. As applications of these results we shall determine when Fpα(K) is a multiplication algebra, and prove the lower majorant property, the uniform localization property and the equivalence of Fourier multipliers.
Appell Type Transformation for the Kolmogorov Operator
Authors: Brzezina Miroslav
Published: June 2010

For the Kolmogorov operator we describe all transformations mapping solutions of the equation Lu = 0 into solutions.
Noether‐Lefschetz Problems for Vector Bundles
Authors: Spandaw Jeroen G.
Published: June 2010

In this paper we generalize two Noether‐Lefschetz theorems for surfaces by L. Ein to varieties of arbitrary even dimension. Our results also generalize the classical Noether‐Lefschetz theorem for complete intersections of even dimension in ℙn.
On Light Edges and Triangles in Planar Graphs of Minimum Degree Five
Authors: Borodin Oleg V. , Sanders Daniel P.
Published: June 2010

This paper presents two tight inequalities for planar graphs of minimum degree five. An edge or face of a plane graph is light if the sum of the degrees of the vertices incident with it is small. A light edge inequality is presented which shows that planar graphs of minimum degree five have a large number of light edges; a graph is presented which shows that this inequality cannot be improved. This completes work contributed to by Wernicke, Grünbaum, Fisk, and Borodin. A graph is presented which shows that a similar light triangle inequality of Borodin is best possible; no such graph had been previously found.
On an A Priori Estimate for Solutions of an Elliptic Equation
Authors: Faierman M.
Published: June 2010

In the investigation of the spectral theory of non‐selfadjoint elliptic boundary value problems involving an indefinite weight function, there arises the problem of obtaining Lp a priori estimates for solutions about points of discontinuity of the weight function. Here we deal with this problem for the case where the weight function vanishes on a set of positive measure.
Circle Maps, Measured Laminations, and Free Group Actions on IR‐trees
Authors: Urbański Mariusz , Zamboni Luca
Published: June 2010

This paper explores the connection between homeomorphisms of the unit circle, codimension‐1 measured laminations on closed surfaces, and free actions of surface groups on IR‐trees.
Nevanlinna Matrices of Entire Functions
Authors: Berg Christian , Pedersen Henrik L.
Published: June 2010

The notion of a pre‐Nevanlinna matrix of entire functions is introduced, and we find necessary and sufficient conditions for an entire function to belong to such a matrix, thereby generalizing previous work of Krein.

If one of the functions in a pre‐Nevanlinna matrix is a polynomial, then the three others arc also polynomials and their degrees differ by at most two. If the functions in a pre‐Nevanlinna matrix are transcendental they have necessarily the same order, type and indicators.
Aromatic Ring‐Fused Carborane‐Based Luminescent π‐Conjugated Polymers
Authors: Kokado Kenta , Tominaga Masato , Chujo Yoshiki
Published: June 2010

A series of π‐conjugated polymers linked by benzocarborane (1,2‐(buta‐1′,3′‐diene‐1′,4′‐diyl)‐1,2‐dicarbadodecaborane) were synthesized via Sonogashira–Hagihara polycondensation reaction. The opened molecular structure of diiodo monomer containing benzocarborane resulted in fast polymerization and high molecular weights. The obtained polymers were fully characterized by 1H, 13C, and 11B NMR spectroscopies. UV‐vis absorption and photoluminescence studies revealed the acceptor‐profile of benzocarborane. Unlike the polymers linked by o‐carborane, these polymers exhibited strong luminescence in the solution state, presumably because the inductive effect of carborane is dominant, rather than cage‐π interactions.

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When does Parkinson's disease begin?
Authors: Gaig Carles , Tolosa Eduardo
Published: June 2010

Pathological and neuroimaging studies have shown that in Parkinson's disease (PD) there is a “subclinical” or “premotor” period during which dopaminergic neurons in the substantia nigra (SN) degenerate but typical motor symptoms have not yet developed. Post‐mortem studies based on nigral cell counts and evaluating dopamine levels in the striata, and imaging studies assessing the nigrostriatal pathway in vivo, have estimated that this time period could last 3 to 6 years. In addition, emerging evidence indicates that the neuropathological process of PD does not start in the SN but more likely elsewhere in the nervous system: in the lower brainstem and the olfactory bulb, or even more distant from the SN, such as in the peripheral autonomic nervous system. Patients with PD frequently can present non‐motor symptoms, such as hyposmia or constipation, years before the development of classical motor signs. The physiopathology of these “premotor” symptoms, though still unclear, is currently thought to be related to early involvement by the pathological process underlying PD of non‐dopaminergic lower brainstem structures or autonomic plexuses. However, the answer to the question “when does PD start” remains uncertain. Here, we review clinical, pathological, and neuroimaging data related to the onset of the pathological process of PD, and propose that its onset is non‐motor and that non‐motor symptoms could begin in many instances 10 and 20 years before onset of motor symptoms. The variable course of the disorder once the motor symptoms develop, suggests that the start and progression of premotor PD is also highly variable andgiven the heterogeneous nature of PD, may differ depending on the cause/s of the syndrome. When and where the neuropathological process develops in PD remains uncertain. © 2009 Movement Disorder Society
The economic and environmental benefits of weather forecasts for salting operations in Devon
Authors: Ackerman J A
Published: June 2010

This paper sets out to show that even with a winter climate which is relatively mild, compared with conditions experienced by some European countries, Devon can save money and minimise the effect on the environment by employing sophisticated technology together with a forecast aimed specifically at road‐surface conditions. In Devon, on many nights during the winter, the forecast minimum road temperatures hover around freezing and therefore the decision to salt is not straightforward. A system has been developed in Devon which combines use of the forecast with sensor, radar and satellite data, thermal maps and a Control and Information Room which is manned 24 hours a day. Staff in the control room monitor road conditions so that salting operations can be properly timed or cancelled if conditions are ‐warmer than expected. The system has been successful in realising both economic and environmental benefits to Devon and has provided an effective and efficient service to the public in the county.
Weather forcasting procedures in an environmental programme for agricultural assistance
Authors: Ciminelli M G , Coretti C , Betello G , Priolo A , Terpessi C , Bonelli P , Redaelli G
Published: June 2010

The purpose of this paper is to give a general description of the project TERRA del Sud and to present the activities carried out as far as meteorological weather forecasting is concerned. TERRA del Sad it a system for the aquisition, processing and dissemination of environmental data, and is designed mainly to support agricultural practices and decision making in agricultural planning. Several meteorological procedures have been developed for weather forecasting. A system for the processing and displaying of meteorological images and data has been developed for analysis and nowcasting and simple methods of statistical post‐processing are applied to the ECMWF model outputs for short‐ and medium‐range forecasting of precipitation and temperature. Some preliminary results and future developments are presented.
Towards a new role for the Royal Meteorological Institute in Belgium's civil defence and emergency planning policies: The GIDS Project
Authors: Vandenberghe P
Published: June 2010

Belgium's Civil Protection organisation, like any other public service these days, has to reorganise itself because of changes m the socio‐economic climate. In a changed society where industrial and technological risks are perceived more sharply, this organisation, which was born in the Cold War era, is nowadays more concerned with fighting industrial accidents and coordinating emergency planning activities. In this context, a project for a digitalised emergency planner is being launched with the support of the European Community. In this so‐called GIDS system, a dispersion module is indispensable. Because of the urgency of the needs of risk management, the meteorological input for it will have to he provided very rapidly, frequently and m great detail. To meet these specific needs the meteorological services may have to consider offering new kinds or new formats of ‘nowcast’ calculations. The conclusion is that, with the various meteorological services rethinking their tasks, new‐technology projects such as the CIDS system may engender a new kind of collaboration.
On the ‘state of the art’ in local weather forecasting
Authors: Balzer K
Published: June 2010

Based partly on more than 20 years of evaluating local weather forecasts in Germany, a comprehensive analysis of the verification results of synoptic, statistical and short‐ and medium‐range forecasts was carried out in order to obtain some insight into the present ‘state of the art’ in local weather forecasting. This ‘state’ is characterised by (a) striking improvements in skill, especially for the three‐to‐six‐day period; (b) an absence of significant progress in very‐short‐range forecasting, especially for aviation purposes and rare events; (c) an important role for statistical interpretation of medium‐range forecasting products; (d) an increasing importance of direct model output for some short‐range predictands; and, finally, (e) the urgent necessity to combine all the relevant forecast information m an optimum manner in real time.
A modern teaching tool for cyclone development and structure
Authors: Saraber M J M , Heijboer L C
Published: June 2010

A simple cyclone model is presented as a new and modern tool for use in education and training in synoptic‐dynamic meteorology. The model has been programmed on an IBM‐compatible personal computer under DOS and is used as a teaching tool by the Royal Dutch Air Force and at the Department of Meteorology of Wageningen Agricultural University. The model is based on an approximate analytical solution of the equations of motion. This solution is capable of generating a realistic mature mid‐latitude cyclone and its development in time. Several basic parameters of the solution can be varied, leading to different characteristic types of cyclone structure and development.
The dependence of gust factor probabilities on convective activity: Analysis conducted for Eurotunnel
Authors: Bradbury Wms , Deaves D M
Published: June 2010

The ratio of the maximum gust in an hour to the mean wind for the how is the ‘gust factor’. Extreme value analysis of gust factors was conducted as part of the design studies for Eurotunnel's Wind Alert System. This analysis indicated that the population of gust factors was mixed, suggesting that two different types of mechanism cause hourly gust maxima. Various investigations confirmed this indication and identified the two mechanisms. During the majority of hours the gust factor is a measure of the maximum gust due to the turbulent fluctuations of the atmospheric boundary layer. However, during a substantial minority of hours it is a measure of a gust caused by a ‘convective’ meteorological event such as a thunderstorm, squall line or heavy shower. The latter mechanism causes occasional exceptional gust factors, which can be of dominating importance for a transport system which must react when there is a risk of severe gusts.
Development of premium telephone weather services: A partnership between the public and the private sectors
Authors: Farrow R.
Published: June 2010

This paper outlines the background to the changes in the Met. Office telephone weather services and considers the effects chat this has had in the market place for readily available public information services. The launch of Weathercall and related services, the agreement between the Met. Office and Telephone Information Services plc ‐ which was one of the very first commercial agreements for o. form of joint venture between the public and private sectors ‐ has proved to be very successful. The partnership has exploited new market opportunities for premium, value‐added information services and greatly increased Met. Office revenues. The paper also considers ways in which telephone weather services can diversify into new ventures, directions and communications technologies in order to open up new revenue‐generating apportunties without creating demands for substantial additional resources within the Met. Office.
The separation of rain and hail using single polarisation radar echoes and IR cloud‐top temperatures
Authors: Hardaker P J , Auer A H
Published: June 2010

A previous study has combined infrared cloud‐top temperature and single polarisation radar reflectivity to delineate between had and no‐hail situations and also to estimate had diameter assuming a mono‐disperse drop‐size distribution. The ‐work presented here builds on this previous study, to formalise the empirically derived results into an algorithm that is intended to be of benefit to an operational forecast system.
Gust factors within frontal depressions at Rio, Greece
Authors: Ahmed Sharif
Published: June 2010

Wind gust factors are determined from data obtained on the south shore of the Rio‐Antirio Strait, at the western entrance of the Gulf of Corinth, during the passage of frontal depressions. It was found that in this region the wind gusts decrease as the wind speed increases. The measured gust factors fall in‐between those used for structural design in the United Kingdom and those used in the United States.
A case study of a mesoscale trapped gravity wave accompanied by severe weather
Authors: Rasmussen Erik A
Published: June 2010

The unexpected development of a mesoscale disturbance accompanied by severe weather in the form of strong convection, dense snow and strong gusty winds at a synoptic situation where most of Denmark would normally he sheltered by the Norwegian mountains is discussed. Using all the meteorological data available, including a variety of non‐synoptic data, supported by a linear model, it is concluded that the phenomenon which caused the outbreak of severe weather was a low‐level ‘trapped’ or ‘ducted’ gravity wave.
The directional‐dependence of the enhancement of rainfall over complex orography
Authors: Weston Keith J , Roy Marjory G
Published: June 2010

Rainfall over Scotland is analysed to determine the distributions of rainfall amount associated with flow from different directions. The dominant effects of orography are dearly displayed, with large amounts of rainfall over the first area of high ground encountered and a rapid decline downwind; indeed, amounts are already declining before the highest ground is reached. This general behaviour applies to all flow directions, including those in which showery precipitation predominates. A simple model of mean orographic enhancement is developed which incorporates cloudwater generation by orographic and synoptic‐scale lifting, the conversion of cloud‐water to rainwater and wind‐drift of falling precipitation. This model allows spatially detailed patterns of rainfall to be inferred. The dependence of rainfall enhancement on wind speed is investigated with the model: over the first area of high ground there is an almost linear increase of rainfall with increasing wind speed, hut over subsequent high ground rainfall amounts decrease with increasing speed, in accord with observations.
The diagnosis and forecast of clear sky ultraviolet levels at the Earth's surface
Authors: Austin J , Barwell B R , Cox S J , Hughes P A , Knight J R , Ross G , Sinclair P , Webb A R
Published: June 2010

A climatology of clear sky ultraviolet (UV) levels, weighted by the sensitivity of human skin, is presented. Away from the tropics the values are shown to be strongly dependent on the time of year, with peak values occurring in midsummer. Near the equator two annual maxima occur due to the twice‐yearly passage of the sun over the equator. The second factor influencing clear‐sky UV levels is the total ozone amount. In mid latitudes, because of lower ozone amounts, UV levels are generally higher around the autumn equinox than at the spring equinox. High UV levels also occur locally in spring due to the Antarctic ozone hole, although Arctic spring values have not yet been significantly affected. Next, total ozone amounts are shown to be related to meteorological parameters. Using a simple representation of the UV level in terms of the solar zenith angle and total ozone amount, an operational procedure for forecasting UV levels is outlined Finally, some comparisons with observed UV levels are presented and a sample UV forecast is shown.
Use of satellite imagery to diagnose events leading to frontal thunderstorms: Part II of a case study
Authors: Browning K A , Roberts N M
Published: June 2010

Convective and mesoscale processes can be diagnosed in some detail by careful scrutiny of high‐resolution satellite imagery. An example is presented in which lines of convergence within warm, moist, low‐level air created a series of very straight rope‐like clouds whose smooth texture, as seen by polar orbiting satellite imagery, indicated that they were capped by a stable lid. The moist air deepened with time until the lid was penetrated and deep convection was observed to break out. The rope‐like clouds occurred near the leading edge of a so‐called dry intrusion and they are believed to have been associated with the kind of multiple cold frontal structure often encountered in such regions.
Methods for assessing the benefits of meteorological services in Australia
Authors: Anaman Kwabena A , Thampapillai Dodo J , Henderson‐Sellers A , Noar Peter F , Sullivan Patrick J
Published: June 2010

A review of several methods for assessing the economic and social benefits of meteorological services provided in Australia is undertaken. Meteorological services discussed are the basic public weather service and several user‐pay specialised services produced by the Australian Bureau of Meteorology for firms in various sectors of the economy. The usefulness and limitations of the contingent valuation technique often used to estimate the economic value of public goods and services (such as the basic public weather service) are reviewed. Methods for valuing the economic benefits of user‐pay services discussed include the direct economic benefits derived from the use of meteorological services for producers and consumers based on the producer and consumer surplus concepts, simulation modelling incorporating economic optimisation based on the cost–loss ratio technique and cost function analysis to establish the effect of the quality of weather information on the operating costs of a business firm. The social or non‐economic benefits of meteorological services are also discussed, including the difficulty of placing monetary values on these benefits.
Fog forecasting in Cuba. Neural networks versus discriminant analysis
Authors: Naranjo‐Diaz Lino R , Alfonso Arnaldo P
Published: June 2010

Two methods for fog forecasting in Cuba are compared: use of the classical Fisher discriminant function, and the LVQ algorithm developed by the Laboratory of Computer and Information Sciences, Helsinki University of Technology. The relative number of correct forecasts is over 70% for both, which can be considered a good performance. When the learning sample is large enough and nearly equi‐probabalistic, the LVQ algorithm provides a greater number of correct forecasts than those obtained via the Fisher discriminant function. However, the results attained via the LVQ algorithm are not steady when the learning sample is far from being equi‐probabalistic, because the number of fog cases is much reduced. Until larger samples are available for some regions, it will be necessary to use both methods for fog forecasting in Cuba.
Variation in air and sea‐surface temperatures and their effect on anchovy fishing along the south‐eastern Black Sea coast
Authors: Durukanoǧlu H Fehmi
Published: June 2010

This paper deals with the influence of the annual temperature distribution on anchovy fishing in Trabzon and its surroundings (which have been taken to be representative of the coastal region of the south‐east Black Sea). Data used in this study come from two periods: 1960 to 1990 and 1987 to 1992. It is shown that the variation in temperature distribution has no effect on anchovy fishing. Also, it is demonstrated that commercial fishing takes place when the temperature is lower than the annual mean.
Excessive rainfall over the Belgian Ardennes in December 1993: Evaluation of model predictions
Authors: Van Meijgaard Erik
Published: June 2010

December 1993 turned out to be very wet on the European continent. Around 20 December the Meuse basin in Belgium and France was hit by an unusual amount of precipitation, which gave rise to extensive flooding of the Meuse in the Dutch province of Limburg. For a 33‐day period starting on 6 December 1993 the precipitation forecasts for the Belgian Ardennes were evaluated using the observations of 20 Belgian climate stations. Besides short‐term forecasts made with regional models like the HIRLAM, level 2.0, the UKMO‐model and the RACMO/HIRHAM, precipitation prognoses extracted from ECWMF‐forecasts were examined. On average all model predictions were too low, varying from 10% for the 36‐ to 60‐hour (day‐2) ECMWF‐forecast to over 50% for the 6‐ to 30‐hour UKMO‐forecast. On the other hand, the UKMO‐forecast correlated best with the observations (0.85). The rainfall on 20 December, the wettest day, was underestimated by all model predictions, with the exception of the day‐2 ECMWF‐forecast. With the RACMO/HIRHAM a three‐day rerun was made starting from the 1200 UTC ECMWF‐analysis on 18 December 1993. The resulting precipitation on 20 December compared very well with the data. A similarly prepared HIRLAM‐run, however, performed worse compared with the operational run.
Practical subjective application of the omega equation and Sutcliffe development theory
Authors: Carroll Edward B
Published: June 2010

Sutcliffe development theory and the similar omega equation provide an objective framework for the understanding of synoptic‐scale development in the extra‐tropics. Both are widely applied by forecasters in the UK Met. Office, with the omega equation also being used by forecasters working in other meteorological services. Using results from experiments with a quasi‐geostrophic numerical model, this paper examines the pitfalls associated with each, and suggests ways in which these can be avoided. The partitioning between so‐called steering and development terms in the Sutcliffe equation is shown to be misleading, and an alternative form is suggested which is more accurate and circumvents significant cancellation problems associated with the existing form. It is shown that oversimplifiction of the omega equation can lead to it being applied in unsuitable ways. In particular, it is argued that the conversion from omega forcing to vertical velocity is best made at the mid‐tropospheric level, say at 500 hPa, and that therefore diagnostics such asQ‐vectors or their divergence are better applied at this level than, say, at 700 hPa. The so‐called Sutcliffe, or Trenberth, form of the omega equation is recommended as being suitable for subjective application.
Test results from a Mobile Profiler System
Authors: Cogan J
Published: June 2010

A Mobile Profiler System is being developed to provide operational users with atmospheric soundings in near to real time. The reduction of refresh time from the 2 to 12 hours of traditional rawinsonde systems to as short as 3 to 5 minutes should considerably reduce errors caused by time staleness. The mobile profiler combines a small satellite receiver and processor with ground‐based remote‐sensing systems and a portable meteorological ground station. Ground‐based systems include a 924 MHz radar wind profiler, a radio acoustic sounding system for virtual temperature, and a multi‐channel microwave radiometer for virtual temperature and total water vapour and liquid water content. Satellite soundings contain temperature, dew point and the derived variables of wind speed and direction. This paper describes the mobile profiler, provides a very brief outline of the combined sounding technique and presents some results from field tests. Comparisons with rawinsonde soundings nearly coincident in space and time provide an indication of the accuracy of the system. For the merged soundings, average standard deviations and means for virtual temperature were about 1.5 to 2.0 K and ±0.5 K, respectively. Preliminary results for wind speed suggested values consistent with those reported in the literature, but were inconclusive for wind direction.
A comparative real‐time trial between the UK Met. Office and Oceanroutes to predict road surface temperatures
Authors: Thornes John E
Published: June 2010

A comparative trial between the Met. Office and Oceanroutes to predict road surface temperatures for a motorway site in Cumbria was held in the spring of 1994. Hourly data for 26 nights when the minimum road surface temperature was equal to or less than 5 °C have been analysed and the results show no significant difference between the accuracy of the forecast for the two organisations. An end‐user specification for road weather forecast providers is also presented.
On estimating extreme wind speeds from short‐period data
Authors: Ahmed Sharif I.
Published: June 2010

Two methods based on the Weibull distribution were used to estimate the extreme wind speeds, with recurrent intervals of 50 and 100 years, from short‐period data. Three years of data were separated into periods of one, two and three years. For each period we applied the least‐squares fit method and the mean wind speed and the standard deviation method, and estimated the extreme wind speeds. Also, we used the classical method of moments to estimate the extreme speeds from the three years of data. The extreme wind speeds estimated by these two methods were found to be in agreement with those processed by the classical method of moments.
The Farnborough Storm—evidence of a microburst
Authors: Waters A J , Collier C G
Published: June 2010

Observations from radar, satellite and conventional ground‐based sources are shown as evidence for the occurrence of a microburst during a severe thunderstorm at Farnborough, Hampshire, UK on 24 May 1989. The data are compared with published analyses of microbursts in the USA, and it is concluded that the microburst observed in the UK is comparable. A descriptive model of the evolution of the gust front and microburst is proposed.
Extreme warm frontal icing on 25 February 1994 causes an aircraft accident near Uttoxeter
Authors: Pike W S
Published: June 2010

An active, double warm‐frontal zone, aligned WNW‐ESE over the British Isles, produced copious precipitation over a wide area from southern Scotlant to the English Midlands during the evening of 25 February 1994. A turboprop cargo aircraft carrying Royal Mail parcels from Edinburgh to the intended destination of Coverntry suffered severe icing during its descent from 18000 ft over Manchester Airport, flying SSE wards in frontal nimbostratus. Then, some freezing rain was encountered below about 3000 ft over snow‐covered ground during the final stages of the flight. At one time, three of the four engines had ‘flamed‐out’, and subsequent attempts to re‐start both of the failed starboard (windward) side engines were unsuccessful. While the official report criticises the crew for following incorrect drills, and for not using their weather radar; eventually the asymmetric build‐up of ice on the windward‐side airframe and dead engines made the aircraft uncontrollable.
New estimates of probable maximum precipitation in South West England
Authors: Clark C
Published: June 2010

Two methods have been used to estimate the probable maximum precipitation (PMP) over South West England. The first is based on an analysis of rainfall frequency data; the second uses depth duration data from rare storms. Both methods give results of around 500 mm for the 24‐hour PMP, which for many parts of the region is considerably higher than that given by the Flood Studies Report. By relating PMP to average annual rainfall, new maps of the distribution of PMP over South West England were produced. Values of PMP are highest on low ground, reflecting the effect of convectional processes in these areas.
Weather forecasting for aviation and marine operations in the Antarctic Peninsula region
Authors: Wattam S , Turner J
Published: June 2010

An account is given of one Austral summer's experience of forecasting for flying activities and marine operations around the Antarctic Peninsula. Data available included surface and upper‐air observations, analyses and forecasts from the UK Meteorological Office global, 19‐level model and AVHRR satellite imagery. The numerical analyses and forecasts provided good guidance and correctly represented most of the synoptic‐scale features. A number of mesoscale disturbances affected the central Peninsula area and the AVHRR imagery was very valuable in allowing the development and track of these systems to be followed. The major problems were the absence of observations to the west of the Peninsula, the lack of radiosonde ascents from the Peninsula itself and the complexity of local wind systems as a result of the topography. Forecasting frontal activity over the ocean areas was also very difficult because of the unavailability of precipitation forecasts in the GRIB data.
Use of INSAT winds for better depiction of monsoon depressions over the Indian region
Authors: Mahajan P N , Talwalkar D R , Chinthalu G R , Rajamani S
Published: June 2010

This study is aimed at evaluating the impact of non‐conventional winds using data obtained by INSAT satellites over the Indian region. The emphasis is on whether the satellite‐derived wind data improve the depiction of monsoon system, flow patterns, the centre of the system, etc. in the objective analysis of the wind field. For this purpose, monthly climatological normals of the wind field are considered as the initial guess field and then objective analyses of the wind field are performed, first using only conventional winds over the land areas and subsequently including winds constructed from cloud‐motion vectors at 850 and 700 hPa. This experiment was performed for the period of 19–21 September, 1991, when a monsoon depression formed over the Bay of Bengal. Verification of these analyses were made by comparing them with carefully drawn subjective analyses. It is inferred that INSAT winds have a positive impact on the objective analysis, and improvement in the analysis is more marked over the data‐void regions of the Arabian sea and the Bay of Bengal. The results presented in the study reveal that INSAT winds are of potential use in the objective analysis of the wind field, thus giving a better depiction of monsoon depression over the Indian region.
The impact of radar and raingauge sampling errors when calibrating a weather radar
Authors: Seed A W , Nicol J , Austin G L , Stow C D , Bradley S G
Published: June 2010

This paper investigates the impact of sampling errors on the estimation of the parameters of the relation Z = aRb used in the measurement of rainfall (R) from radar reflectivity (Z). Simulation results show that, at levels of sampling errors likely to be observed in real data sets, of the order 100 gauge and radar observation pairs are required to estimate a with an accuracy better than 15% and b better than 10%. Errors in radar rainfall estimates for rain rates less than 15 mm h−1 are insensitive to the Z‐R parameters. High‐resolution measurements from a vertically pointing radar (300 to 400 m above ground level, 1‐minute averages) are compared with raingauge measurements taken at the radar site during a period of widespread rainfall. The radar provided surprisingly poor estimates of rain rates, with mean standard errors of 80% for rain rates less than 2 mm h−1. The auto‐correlations of the residuals in the radar estimates were found to be very low after only 2 minutes, leading to the conclusion that radar estimates of rainfall intensities should be made at a high space/time resolution and then averaged so as to reduce measurement errors arising from sampling problems.