bluuebunny/crossref_metadata_2025 huggingface dataset:
INFLATION, EXPECTATIONS, AND THE POLITICAL ECONOMY OF CONSERVATIVE BRITAIN, 1951–1964
Authors: BOOTH ALAN
Published: July 2002

Analysis of policy after 1945 has been profoundly shaped by the idea of a post-war
settlement, which is increasingly viewed as inherently inflationary. For much of the period 1951–64,
British economic policy was centrally focused on reducing inflation. The extension of sterling's
convertibility in the mid-1950s forced British policy-makers to be sensitive to overseas perceptions of
British policy and performance. At the beginning of the Conservative government's period in office,
monetary policy was believed to be the most effective instrument to control inflation, but its limitations
slowly became apparent and created enormous tension between the Treasury and Bank of England. In
the literature stimulated by the Phillips curve, the formation of price expectations is the central element
in inflationary dynamics, and it is argued that after 1955 Conservative policy was driven by the need
to find alternatives to monetary policy to prevent and then limit inflationary expectations. A number
of these initiatives – a steep rise in unemployment and confrontation in pay bargaining – sit
uncomfortably with the idea of the post-war settlement and an alternative perspective on the
Conservative years, emphasizing the Radcliffe committee and the investigations into incomes policy, is
proposed.
INTERVENING IN THE PUBLIC SPHERE: GERMAN GOVERNMENTS AND THE PRESS, 1815–1870
Authors: GREEN ABIGAIL
Published: July 2002

This article argues that the growth of a free press in nineteenth-century Germany went hand in hand with the growth of an official, government-sponsored, press. The collapse of pre-publication censorship in 1848 prompted the development of increasingly sophisticated (and relatively successful) press control strategies by German governments, in the shape of official newspapers, semi-official newspapers, and indirect government press influence. Government press policy was essentially reactive. Changes in press policy were usually prompted by political events. Furthermore, government press coverage was forced to reflect shifts in public opinion in order to maximize readership of official propaganda. Government press policy focused not just on the dissemination of pro-government opinion, but also on the dissemination of pro-government information, probably the most effective form of government press influence. News management was subtle, and targeted small circulation local newspapers, rather than high profile opposition newspapers. Consequently, historians have tended to overlook the scale of government news management.
DREAMS OR DESIGNS, CULTS OR CONSTRUCTIONS? THE STUDY OF IMAGES OF MONARCHS
Authors: HACKETT HELEN
Published: July 2002

This historiographical review surveys studies by cultural historians of images of monarchs, including Elizabeth I, Mary Queen of Scots, Charles I, and Victoria. These are not biographies, but analyses of the diverse and often contradictory representations of monarchs in their own times and afterwards. The review considers the variety of approaches in the field, from iconographical decoding to political history to the application of psychoanalysis to a national culture. It discusses the extent to which queens tend to be conflated to an enduring model of idealized femininity; how seriously we should take representations of monarchs as sacred; and the incorporation of sexuality in the royal image. It considers resistance as well as assent to the royal image, and how far the royal image as art object can become detached from the ideology which produced it. It concludes by observing our mixed motivations for interest in past ‘cults’ of monarchs, seeking in them at once the exotic difference of the past and comparisons with public figures of our own time.
THE RUSSIAN REVOLUTION AFTER THE FALL OF COMMUNISM
Authors: READ CHRISTOPHER
Published: July 2002

Nicholas II. Emperor of all the Russias. By D. Lieven. London:

Pimlico, 1995. Pp. 292. ISBN 0-719-54994-9. £10.00.

The Russian Revolution, 1917–1921: a short history.

By J. D. White. London: Edward Arnold, 1994. Pp. 312. ISBN 0-340-53910-0.

£12.99.

The origins of the Russian civil war. By G. Swain. London:

Longman, 1995. Pp. 296. ISBN 0-582-05968-2. £13.99.

Behind the front lines of the civil war: political parties and

social movements in Russia, 1918–1922.

By V. N. Brovkin. Princeton: Princeton University Press, 1994. Pp. 455.

ISBN 0-691-03278-5. £40.00.

America's secret war against Bolshevism: U.S. intervention
in the

Russian civil war, 1917–1920.

By D. S. Foglesong. Chapel Hill and London: North Carolina University Press,
1995.

Pp. 386. ISBN 0-807-82228-0. $45–00.
FASCIST FOREIGN POLICY AND OFFICAL ITALIAN VIEWS OF
ANTHONY EDEN IN THE 1930s
Authors: MALLETT ROBERT
Published: July 2002

This article examines the relationship between Anthony Eden, British minister for
League of Nations' affairs (1935) and foreign secretary (1935–8), and Benito Mussolini's Fascist
regime within the context of Italian foreign policy in the later 1930s. It outlines the precise aims and
objectives of Mussolini's expansionist policies over the period 1935–8, assesses the accuracy of Eden's
interpretation of them and, in turn, discusses official Italian diplomatic perceptions of Eden. It
specifically challenges Renzo De Felice's view that for Mussolini, the Italian conquest of Ethiopia
(1935–6) marked the limit of Fascist expansionism. Furthermore, it contests his theory that the
dictator did not pursue an Italo–German alliance that would drive an Italian imperialist war against
Britain and France in the Mediterranean and Red Sea. Anthony Eden had been fully aware of such
an intention, and had been targeted by the regime as Italy's ‘public enemy number one’, precisely
because he fully comprehended what lay at the heart of Mussolini's brand of Fascism.
A RESPONSE TO SABRI SAYARI'S REVIEW OF THE KURDS AND THE FUTURE OF TURKEY (NEW YORK: ST. MARTIN'S PRESS, 1997), BY MICHAEL M. GUNTER, IJMES 31 (1999).
Authors: Gunter Michael M.
Published: July 2002

Sabri Sayari's review of my book The Kurds and the Future of Turkey concludes that “despite some … merits,” my book “fails to make a significant contribution to the existing scholarship and knowledge about an important and complex issue.” Given some of the criticisms he has made to arrive at his conclusion, one might instead conclude that my book fails to make the contribution Sayari, the executive director of the Institute of Turkish Studies, would have liked it to make. Because my subject concerns an increasingly important issue, I believe it would serve a useful scholarly purpose for me to reply to his criticisms.
Bourgeois Mentality and Socialist Ideology as Exemplified by Clara Zetkin's Constructs of Femininity
Authors: Unludag Tania
Published: July 2002

Clara Zetkin (1857–1933) remains one of the most famous figures in the history of the German and international Left. She rose to prominence as a social democrat beginning in 1890 and became a Marxist and, as of 1919, a member of the high-ranking cadre of the KPD; she was an activist of the Second International, starting in 1889, and belonged to the Executive Committee of the Communist International (EKKI) in the 1920s. She is known in history primarily as the leader and chief ideologue of the socialist, and later the international communist, women's movement, but is also a popular figure in the leftist women's movement of the twentieth century. Zetkin, the founder of International Women's Day, is still widely depicted as a heroine. However, in light of recent research conducted in Berlin and Moscow and from the perspective of the history of mentalities, the tendency to mythologize her needs to be questioned. This essay on Clara Zetkin's constructs of femininity is part of a biography oriented toward a history of mentalities, in which the socialist and communist Zetkin is presented in the entire societal context of her times, perceived as a contemporary of the late nineteenth and early twentieth centuries. From this perspective, it is precisely Zetkin's comments on the women's issue that mirror the influences of Social Darwinism and biological discussion at the turn of the century in Germany. The ideas held by the leader and theoretician of the international socialist women's movement on the “liberation of women” from “gender slavery” and “class bondage” were not aimed at pursuing an autonomous process of emancipating women for their own sake, but at pursuing a well-structured and directed process of educating them that would end up turning them into a new physically and mentally improved “consummate woman” who would efficiently serve the socialist society.
The effect of planting combinations and weeding on the growth and yield of component crops of maize/bean and maize/pumpkin intercrops
Authors: TEMBAKAZI SILWANA T. , LUCAS E. O.
Published: July 2002

A diagnostic survey carried out in 1997 to obtain baseline information on the farming situation in Transkei area of South Africa, showed that agriculture in this area was characterized by low technological inputs which invariably led to low agricultural outputs. The main farming system of the majority of the farmers (98%) was based on intercropping involving maize, beans and pumpkin combined in an haphazard fashion.

Based on the above findings, two field experiments were set up in 1998 designed to bring out the best planting combinations for maize/beans and maize/pumpkin intercrops which could be introduced to the farmers. Effect of weeding on the intercrops was also investigated.

In both intercrops, intercropping adversely affected the plant heights and circumferences of the component crops. Also, the yield of the individual crop in each intercrop was depressed by intercropping compared with its sole yield. In maize/beans intercrop, the yield of maize was depressed by 15% and that of beans by 13%. However in both intercrops, productivity as measured by Land Equivalent Ratio (LER) was the highest with maize at 10000 plants/ha combined with beans at 150000 plants/ha (2·60) with weeding while the combination with the best LER (1·50) in maize/pumpkin intercrop was at 30000 plants/ha of maize combined with pumpkin at 2500 plants/ha, with weeding. However, before any final recommendation is made, the profitability of each combination has to be considered.

Weeding was found to enhance intercrop yields in maize/bean combination by 35% and by 30% in maize/pumpkin combination.
Effects of environment on spore germination and infection by broad

bean rust (Uromyces viciae-fabae)
Authors: JOSEPH M. E. , HERING T. F.
Published: July 2002

Urediospores of U. viciae-fabae (broad bean rust)

germinated well in the range 5–26 °C, with fastest

germination at 20 °C. Exposure to 30 °C gave poor germination

and damaged the spores. Infection of Vicia faba leaves

depended on a moisture film. At 20 °C some infection occurred

with only 4 h leaf wetness, but longer wet periods up to 24 h gave

increased infection. At lower temperatures, the infection process was

slower and final pustule numbers were smaller. Spore germination was

delayed by daylight and by all artificial light sources that

contained far-red (700–800 nm) wavelengths. The delay was

increased at higher light intensities. When spores were subjected to

alternating periods of light and darkness, it was found that 40 min

of darkness was sufficient for the irreversible induction of

germination at 20 °C.
The introduction of animal traction into inland valley

regions. 3. Different cultivation techniques for maize
Authors: DIJKMAN J. T. , LAWRENCE P. R.
Published: July 2002

Maize was grown in the upland areas surrounding an inland valley

in central Nigeria in a randomized

block experiment using six cultivation techniques (manual cultivation with

a hand hoe (MC);

ploughing in both directions to throw up a ridge (DPL); single ploughing

with the seed placed on the

ridge (SPL); ridging with a wooden, single tine, locally made

‘bush’ plough (BPL); single ploughing

with the seed placed in the furrow (FPL) and ridging with a conventional

ridger (RID) with or

without pre-emergence herbicide (PEH) with two replicates. Initial

cultivation times ranged from 29

to 70 h/ha (BPL<RID<SPL<FPL<DPL<MC). Total weeding

time ranged from 220 to

512 h/ha (MC<DPL<RID<FPL<BPL<SPL) with PEH and from
431

to 763 h/ha (MC<SPL<DPL<RID<FPL<BPL) without PEH. Ox

cultivation techniques were associated with

higher weeding times and larger weed burdens. Total times for all

field operations were 568–758 h/ha

(MC<FPL<DPL<BPL<SPL<RID) with PEH and 791–870

h/ha (BPL<MC<SPL<DPL<RID<FPL) without PEH. Thus,

although ox cultivation saved time at the most critical time

of year (cultivation and planting), it did not save time overall.

Amongst the ox cultivation techniques, work inputs were

6·3–34·1 MJ/ha (BPL<FPL<SPL<RID<DPL)

and draught forces 387–1377N (BPL<DPL<FPL<SPL<RID).

Yields of maize cobs were 2·55–4·0 t/ha

(SPL<FPL<MC<RID<DPL<BPL) with PEH

and 1·65–3·55 (RID<BPL<FPL<DPL<MC<SPL)

without PEH. Except for SPL, PEH was

associated with increased yield especially when used with ox cultivation.

As regards crop yield, time inputs and work input, there was no

advantage to be gained from using

a separate (and expensive) ridger for maize compared with a locally

made plough or the plough also used for the main cash crop (rice).

At 1992 prices, the cost of PEH was about the same per ha as the

price of labour saved on weeding,

but additional benefits associated with PEH use were the avoidance of

mid-season labour bottlenecks and an overall increase in crop yield.
Perennial ryegrass endophytes in Galicia,

Northwest Spain
Authors: OLIVEIRA J. A. , ROTTINGHAUS G. E. , COLLAR J. , CASTRO P.
Published: July 2002

Fifty-six half-sib families of perennial ryegrass

(Lolium perenne), derived from wild populations in

Galicia, were examined for the presence of perennial

ryegrass endophytes; 28 were endophyte-infected (E+) and 28 were

endophyte-free (E−). All families were established in spaced-plant

nurseries and trial plots at two locations in Galicia, in 1992.

E+ families had a significantly (P<0·05) higher first

cut, spring and total yield than E− families at one

location in the third year after

planting. At this location, water deficit was about 75%

higher than at the other location in all three

years of study. Endophyte did not affect crown rust

susceptibility or forage quality (crude protein,

water-soluble carbohydrate and in vitro digestibility).

Ergovaline alkaloid concentration in the 28 E+

families varied from 0 to 0·55 μg/g dry matter (DM)

(mean 0·15), with 14 families containing levels

of ergovaline >0·1 μg/g DM. Thus endophyte infection

may benefit the host in drought-prone areas

of Galicia, with an increased chance of E+ plants being favoured by

either natural or artificial selection.
Competition and productivity in crop mixtures: some
properties of productive intercrops
Authors: JOLLIFFE PETER A. , WANJAU FREDRICK M.
Published: July 2002

Inverse yield–density relationships were used to evaluate how competitive balances in mixed plant
species associations may influence productivity, as measured by three indices : Relative Yield Total
(RYT), Relative Land Output (RLO), and Total Land Output (TLO). Parameters of the inverse
relationships, which express competitive influences and plant growth potential in the absence of
competition, were incorporated into expressions used to predict RYT, RLO and TLO. Initial
parameter values were derived from 25 experiments on binary species mixtures, and parameter values
were systematically varied over a 100-fold range. Response to parameter manipulation was also
investigated in five specific binary associations representing a broad range of relative mixture
productivity. As indicated by RLO or RYT, and in accord with ecological concepts of niche
differentiation, high productivity of mixtures relative to monocultures occurred if between-species
competition was low. As indicated by TLO, the total combined productivity of the mixed species was
enhanced by higher potential growth per plant in the absence of competition. Lower within- and
between-species competition also increased TLO. There was a significant positive correlation between
RYT and RLO. Relative and total measures of mixture productivity, however, showed different
responses to parameter manipulation, and were not correlated.
A Reply
Authors: MURPHY M. , HEY K. , O’DONNELL M. , WILLIS B. , ELLIS J. D.
Published: July 2002

James questions the validity of the very tentative statement made in the final sentence of our paper. Our claim concerned the proportion of twins in Britain in the 1990s that might have arisen through subfertility treatment and was linked to the s
uggestion that the natural twinning rate might still be in decline. If this were true, we, like James, would regard that prospect with concern.
Relatedness of Staphylococcus aureus isolates from bovine mammary gland suffering from mastitis in a single herd
Authors: ZSCHÖCK MICHAEL , SOMMERHÄUSER JÜRGEN , CASTANEDA HUGO
Published: July 2002

Mastitis can be caused by a number of bacteria (Philpot & Pankey, 1975), among
which Staphylococcus aureus is one of the most important, responsible for considerable
economic loss to the dairy industry (Jasper et al. 1982). Carrier rates have been
studied extensively in dairy herds suffering from mastitis (Davidson, 1961, 1963).

Subtyping bacteria is an important epidemiological tool; for example, antimicrobial
susceptibility patterns (antibiograms) have been used for typing Staph.
aureus in human medicine (Gillespie et al. 1990). Staph. aureus of bovine origin can
be divided into several categories by biotyping (Devriese, 1984). Phage typing has
proved useful in differentiating mastitis strains (Mackie et al. 1987) and plasmid
profiling has been valuable in epidemiological studies of bovine Staph. aureus
(Baumgartner et al. 1984).

During the last 5 years genomic fingerprinting of Staph. aureus became a powerful
tool for epidemiological typing. Numerous techniques for comparison of staphylococcal
isolates have been developed and are becoming important in investigations
of strain origin, clonal relatedness and epidemiology.

The aim of this study was to determine the epidemiology of Staph. aureus isolates
from mammary glands of cows from a single herd using modern molecular typing
techniques, and to assess whether the same strain constantly colonizes the udder or
cows are repeatedly infected by different strains. We investigated 26 Staph. aureus
isolates obtained from quarter milk samples from 16 cows. These isolates were
characterized biochemically, by their antibiotic resistance pattern, by two
polymerase chain reaction (PCR) methods on the basis of coagulase (Coa) gene and
protein A (Spa) gene (X region) polymorphism and by macrorestriction analysis of
chromosomal DNA using pulsed-field gel electrophoresis (PFGE).
Monitoring lactic acid bacteria strains during ‘Cacioricotta’ cheese production by restriction endonuclease analysis and pulsed-field gel electrophoresis
Authors: BLAIOTTA GIUSEPPE , MOSCHETTI GIANCARLO , SIMEOLI ERMENEGILDA , ANDOLFI ROSAMARIA , VILLANI FRANCESCO , COPPOLA SALVATORE
Published: July 2002

Lactic acid bacteria (LAB) play an important role in food fermentation, as the
products obtained with their aid are characterized by hygienic safety, storage
stability and attractive sensory properties. A major aim of the research in this field
is the selection of LAB strains that could be used. Hence it is very important to be
able to apply a reliable method to distinguish a particular strain specifically and
unambiguously, which allows studies of population dynamics of mixed cultures and
monitoring starter strains during fermentation (Ramos & Harlander, 1990).

Molecular methods are a powerful alternative to the traditional differentiation of
bacteria. A highly reproducible method for characterizing and distinguishing closely
related strains, is represented by REA-PFGE (restriction endonuclease analysis by
pulsed-field gel electrophoresis) performed by infrequently cutting endonucleases.
Genetic differentiation of strains in several species of LAB has been successfully
performed by this technique (Moschetti et al. 1997; Villani et al. 1997) obtaining very
clear and reproducible restriction patterns (Moschetti et al. 1998).

In this study selected inoculated strains (lactococci or lactobacilli) were
monitored by REA-PFGE during the whole process of water-buffalo ‘cacioricotta’
cheese-making. This product is a typical and traditional cheese in southern Italy
produced from cow, goat, ewe or water-buffalo milk. The original technology of this
preparation permits the recovery of whey proteins due to the high heat treatment of
whole milk employed, allowing interesting yields to be achieved in terms of cheese.
The use of starters is not common in traditional technology but low acid protection
of the final product suggested the use of LAB as starter (Emaldi et al. 1987).
Expression of a bovine α-lactalbumin transgene in
α-lactalbumin-deficient mice can rescue lactation. In vivo

relationship between bovine α-lactalbumin expression content and

milk composition
Authors: SOULIER SOLANGE , LEPOURRY LAURENCE , STINNAKRE MARIE-GEORGES , MERCIER JEAN-CLAUDE , VILOTTE JEAN-LUC
Published: July 2002

Lowering the lactose content of milk in vivo has
two potential benefits: to develop
milk products for lactose intolerant people (Delmont, 1983) and to produce
a more
concentrated milk, reducing milk storage volume and milking frequency without

affecting the overall fat and protein yields. Lactose synthesis in the
lactating
mammary gland results from the interaction of α-lactalbumin
(α-la) with a Golgian
UDP-galactosyltransferase (EC 2.4.1.22), and it has been suggested that
lactose and
α-la contents are directly related (Fitzgerald et al.
1970). Evidence that α-la is the
only protein responsible for the in vivo induction of
lactose synthesis came recently
from knock-out experiments of the relevant gene (Stinnakre
et al. 1994; Stacey et al.
1995), which disrupt lactation, as lactose-deprived milk of
α-la-deficient mice is
highly viscous. However, although the lactose, fat and protein contents
of the milk
were found to be directly related to the quantity of α-la present

(Stinnakre et al.
1994), only in mice homozygous for the α-la null allele was there
a significant
alteration of milk concentration (Stacey et al. 1995).
Stacey et al. (1995) also
demonstrated that human α-la could substitute for its mouse counterpart
via
homologous recombination.

In the present study, we report the generation of transgenic mice producing
only
bovine α-la by back-crossing animals from four independent
bovine α-la transgenic
lines with α-la-deficient mice. Our work confirms that foreign
α-la can substitute for
the mouse protein and suggests a negative correlation between the
α-la content and protein and fat concentrations in milk.
Purification and characterization of aminopeptidase P from
Lactococcus lactis subsp. cremoris
Authors: McDONNELL MAEVE , FITZGERALD RICHARD , NI FHAOLÁIN IDE , JENNINGS P. VINCENT , O'CUINN GERARD
Published: July 2002

Aminopeptidase P was purified 65·3-fold from the cytoplasm of
Lactococcus lactis subsp. cremoris AM2 with a
5·8% yield. The purified enzyme was
found to consist of one polypeptide chain with a relative molecular mass of 41600.
Metal chelating agents were found to be inhibitory and Mn2+ and
Co2+ stimulated
activity 7-fold and 6-fold respectively. The purified enzyme removed the N-terminal
amino acid from peptides only where proline (and in one case alanine) was present
in the penultimate position. No hydrolysis was observed either with dipeptides even
when proline was present in the C-terminal position or when either N-terminal
proline or pyroglutamate was present preceding a proline residue in the penultimate
position of longer peptides. On the basis of this substrate specificity either
aminopeptidase P or post-proline dipeptidyl aminopeptidase are necessary along
with a broad specificity aminopeptidase to effect complete hydrolysis of casein-derived peptides containing a single internally placed proline residue. However, both
aminopeptidase P and post-proline dipeptidyl aminopeptidase would be required
together with a broad specificity aminopeptidase in order to completely hydrolyse
casein-derived peptides that contain two internally placed consecutive proline
residues. As bitter casein-derived peptides are likely to contain either
single prolines
or pairs of prolines, aminopeptidase P appears to be an important enzyme for
debittering.
Mechanism and kinetics of inactivation at 40–70°C of the

extracellular proteinase from Pseudomonas fluorescens 22F
Authors: SCHOKKER ERIX P. , VAN BOEKEL MARTINUS A. J. S.
Published: July 2002

HPLC size exclusion chromatography experiments showed that during

inactivation at 40–70°C of the extracellular proteinase from

Pseudomonas fluorescens 22F small molecular mass fragments were

formed, indicating that autoproteolysis
was at least one of the major causes of inactivation. The formation of
small molecular
mass fragments and the reaction order indicated that intermolecular autoproteolysis

was more likely than intramolecular autodigestion. This was confirmed by
computer
simulations. The rate constants and the activation enthalpy
(ΔH[Dagger]) and entropy (ΔS[Dagger])
for the reactions of the intermolecular autoproteolysis model were derived

from computer simulations. ΔH[Dagger] and ΔS[Dagger]

of the unfolding reaction were 504 kJ mol−1 and 1252 J
mol
K−1 respectively. ΔH[Dagger] and ΔS[Dagger]

of the refolding reaction were
strongly temperature dependent. The estimates for the enthalpy
(ΔH0) and entropy (ΔS0)

difference between the folded and unfolded state as derived from the reaction

rate constants of unfolding and refolding were subject to large deviations,
owing to
accumulation of errors in the estimation of the kinetic characteristics.
Insulin-independent glucose uptake in growth hormone treated dairy
cows
Authors: ROSE MICHAEL T. , ITOH FUMIAKI , MATSUMOTO MITSUTO , TAKAHASHI YUJI , OBARA YOSHIAKI
Published: July 2002

Our aim was to determine the effect of growth hormone on non-insulin-mediated

glucose disposal in lactating dairy cows. Following 5 d of subcutaneous

injections of either saline or growth hormone, insulin, somatostatin or
insulin plus
somatostatin were infused for 2 h each, in a series of experiments. Coincident
with
this, unlabelled glucose was infused at a variable rate to maintain a constant
plasma
glucose concentration. Glucose, doubly labelled with deuterium, was also
infused for
the calculations of glucose turnover. Plasma insulin levels were reduced
to nearly
zero by the infusion of somatostatin; under such conditions whole body
glucose
disposal should be non-insulin-mediated. Dairy cows treated with growth
hormone,
which had significantly increased milk yields on the day before the experimental

infusions, did not have different levels of whole body non-insulin-mediated
glucose
disposal when expressed in absolute terms. Growth hormone did not affect
non-mammary
non-insulin-mediated glucose uptake estimated by calculation. Growth
hormone significantly inhibited insulin-mediated glucose uptake when plasma

insulin levels were elevated. Glucose uptake during insulin plus somatostatin

infusion was not significantly different from that of the insulin only
infusion.
Free radical formation in freeze-dried raw milk in relation to
its α-tocopherol level
Authors: STAPELFELDT HENRIK , NIELSEN KIRSTEN NYHOLM , JENSEN SØREN KROGH , SKIBSTED LEIF H.
Published: July 2002

Lipid oxidation in milk and dairy products is a chain reaction initiated by
formation of free radicals (Richardson & Korycka-Dahl, 1983). Thanks to intensive
studies on both model systems and actual food, the autocatalytic process, including
the formation of secondary lipid oxidation products from the lipid hydroperoxides
formed initially, is fairly well understood. However, actually predicting the rate at
which the first free radicals leading to spontaneous oxidation are formed in milk from
different cows awaits the development of new analytical methods with higher
specificity and sensitivity (Nicholson, 1993; Barrefors et al. 1995). Such methods
would also be valuable for predicting the stability and shelf life of dried dairy
products, which are determined by oxidative phenomena. Electron spin resonance
(ESR) spectrometry has the potential for detecting the early events in lipid
oxidation, as it is the only spectrometric method that will directly detect the
unpaired electron characteristic of the free radical and it is, moreover, a highly
sensitive method (Brudvig, 1995). ESR spectrometry has recently been shown to
provide quantitative information on the level of free radicals in milk powder that
correlates with the level of secondary oxidation products developed upon
reconstitution and that also correlates with subsequent sensory evaluation (Nielsen
et al. 1997; Stapelfeldt et al. 1997a, b, c).
However, in order to explore further the
potential of this method for raw milk, it was considered valuable to measure the
tendency of milk to form free radicals in relation to its level of α-tocopherol, the most
important lipophilic chain-breaking antioxidant (cf. Kamal-Eldin & Appelqvist,
1996).
Multiple solutions and flow limitation in collapsible channel flows
Authors: LUO X. Y. , PEDLEY T. J.
Published: July 2002

Steady and unsteady numerical simulations of two-dimensional flow in a collapsible channel were carried out to study the flow limitation which typically occurs when the upstream transmural pressure is held constant while flow rate and pressure gradient along the collapsible channel can vary independently. Multiple steady solutions are found for a range of upstream transmural pressures and Reynolds number using an arclength control method. The stability of these steady solutions is tested in order to check the correlation between flow limitation and self-excited oscillations (the latter being a consequence of unstable steady solutions). Both stable and unstable solutions are found when flow is limited. Self-excited oscillations and divergence instabilities are observed in certain solution branches. The instability of the steady solutions seems to depend on the unsteady boundary conditions used, i.e. on which parameters are allowed to vary. However, steady solutions associated with the solution branch before flow limitation where the membrane wall bulges are found to be stable for each of the three different boundary conditions employed. We conclude that there is no one to one correlation between the two phenomena in this two dimensional channel model.
Aerated granular flow over a horizontal rigid surface
Authors: EAMES I. , GILBERTSON M. A.
Published: July 2002

The effect of a vertical gas flow on the dynamics of a coulombic granular material
moving over a horizontal rigid porous surface has been studied experimentally and
theoretically. The presence of a fluidizing gas significantly alters the granular flow
dynamics. When the gas velocity, ug, is below the
minimum fluidization velocity, umf,
the effect of the gas is to reduce the angle of repose θ from the value measured in the
absence of a gas flow. When material is poured from a point source onto a horizontal
surface it forms a pile, which adjusts through episodic avalanching to a self-similar
conical shape. Under these conditions, the development of the pile is determined by
the local force balance on individual particles and its extent may be expressed in
terms of the volume of particles added and the angle of repose. A volume of material
is poured continuously from a point source onto a surface according to Qtα. Below
the minimum uidization velocity, a quasi-static description gives the encroachment
distance of the granular pile as l = (2Q/(2π/3)n−1
tan θ)1/n+1tα/n+1 where n = 1 for a
planar release and n = 2 for an axisymmetric release.

A continuum description of fluidized granular flow has been developed by vertically
averaging the mass and momentum conservation equations and including the
momentum exchange between the gas and granular flow. The bulk movement is
driven along the ground by horizontal gradients of particle pressure and is resisted
by a viscous drag force due to the particles moving horizontally through a vertical
gas flow. Above the minimum fluidization velocity the character of the granular
flow is significantly altered and takes on fluid-like properties. The model predicts the
shape of the fluidized granular pile and that the encroachment distance grows as
l = λnα (Q(ug
+ umf) / ε)1/n+2tα+1/n+2, where ε is the void fraction in the bed and
λnα is a constant. Below the conditions for fluidization
(ug < umf), the pile of granular material
grows quasi-statically when t > t∗, where
t∗ ∼ (εn+1Qug
+ umf) / μ2+n
(umf − ug)2+n)
1/1+n−α corresponds to the critical time when frictional forces are comparable
to gradients of particle pressure and the drag force. Numerical solutions describing the granular flow are presented.

Experimental observations of the shape and extent of planar and axisymmetric
granular flows when α = 1 compare well with theoretical predictions for various
values of particle volume flux Q, time t, and gas flow rate ug. The
mathematical description of fluidized granular flows along rigid surfaces indicates a strong analogy
with buoyancy-driven flows in a porous medium. This analogy permits extension of
our description to include flows down slopes and the effect of internal stratification.
Waves and resonance in free-boundary baroclinic instability
Authors: RIPA P.
Published: July 2002

Eady's model of baroclinic instability has been generalized by including β (the
meridional gradient of planetary potential vorticity) while assuming that total potential
vorticity is uniform. Moreover, the problems of Eady and of Phillips have been
enriched by including a fixed topography or a free boundary (which implies a flow-dependent
geostrophic topography). The most general cases (with β, fixed topography
and a free boundary) of both problems are shown to have nearly identical stability
properties, mainly determined by two Charney numbers: the planetary one and a
topographic one. The question of whether this generalized baroclinic instability problem
can be described by wave resonance or component ‘resonance’ is addressed. By
waves are meant physical modes, which could freely propagate by themselves but are
effectively coupled by an independent basic shear, producing the instability. Components,
on the other hand, are mathematical modes for which the shear is also crucial
for their existence, not just for their coupling, hence the quotation marks around
‘resonance’. In this paper it is shown that both scenarios, components ‘resonance’
and waves resonance, cast light on the free-boundary baroclinic instability problem
by providing explanations of the instability onset (at minimum shear) and maximum
growth rate cases, respectively. The importance of the mode pseudomomentum for
the fulfillment of both mechanisms is also stressed.
Nonlinear Ekman effects in rotating barotropic flows
Authors: SANSÓN L. ZAVALA , van HEIJST G. J. F.
Published: July 2002

In the presence of background rotation, conventional two-dimensional models of
geostrophic flow in a rotating system usually include Ekman friction – associated
with the no-slip condition at the bottom – by adding a linear term in the vorticity
evolution equation. This term is proportional to E1/2
(where E is the Ekman number),
and arises from the linear Ekman theory, which yields an expression for the vertical
velocity produced by the thin Ekman layer at the flat bottom. In this paper, a two-
dimensional model with Ekman damping is proposed using again the linear Ekman
theory, but now including nonlinear Ekman terms in the vorticity equation. These
terms represent nonlinear advection of relative vorticity as well as stretching effects.
It is shown that this modified two-dimensional model gives a better description of the
spin-down of experimental barotropic vortices than conventional models. Therefore,
it is proposed that these corrections should be included in studies of the evolution of
quasi-two-dimensional flows, during times comparable to the Ekman period.
Parameterization of dispersion in two-dimensional turbulence
Authors: PASQUERO C. , PROVENZALE A. , BABIANO A.
Published: July 2002

We investigate the performance of standard stochastic models of single-particle dispersion
in two-dimensional turbulence. Owing to the presence of coherent vortices,
particle dispersion in two-dimensional turbulence is characterized by a non-Gaussian
velocity distribution and a non-exponential velocity autocorrelation, and it cannot
be properly captured by either linear or nonlinear stochastic models with a single
component process. Based on physical and dynamical considerations, we introduce
a family of two-process stochastic models that provide a better parameterization of
turbulent dispersion in rotating barotropic flows.
Interaction of a shock with a longitudinal vortex
Authors: ERLEBACHER G. , HUSSAINI M. Y. , SHU C.-W.
Published: July 2002

In this paper we study the interaction of a shock with an axisymmetric
longitudinal
vortex. A linearized analysis for small vortex strength is performed, and compared
with results from a high-order axisymmetric shock-fitted Euler solution. It is
confirmed that for weak vortices, predictions from linear theory agree well
with results
from nonlinear numerical simulations at the shock location. To handle very strong
longitudinal vortices, which may ultimately break the shock, we use an axisymmetric
high-order essentially non-oscillatory (ENO) shock-capturing scheme. Comparisons
of shock-captured and shock-fitted results are performed in their regions of common
validity. We also study the vortex breakdown as a function of Mach number ranging
from 1.3 to 10, thus extending the range of existing results. For vortex
strengths
above a critical value, a triple point forms on the shock, leading to a Mach disk.
This leads to a strong recirculating region downstream of the shock and a secondary
shock forms to provide the necessary deceleration so that the fluid velocity
can adjust to downstream subsonic conditions.
Oscillatory flow past a circular cylinder in a rotating frame
Authors: KUNKA M. D. , FOSTER M. R.
Published: July 2002

Because of the importance of oscillatory components in the oncoming

flow at certain oceanic topographic features, we investigate the oscillatory
flow

past a circular cylinder

in an homogeneous rotating fluid. When the oncoming flow is non-reversing,
and for

relatively low-frequency oscillations, the modifications to the equivalent

steady flow arise principally in the ‘quarter layer’ on the
surface of

the cylinder. An incipient-separation criterion is found

as a limitation on the magnitude of the Rossby number,

as in the steady-flow case. We present exact solutions for a number of
asymptotic

cases, at both large frequency and small nonlinearity. We also report numerical

solutions of the nonlinear quarter-layer equation for a range of parameters,
obtained

by a temporal integration. Near the rear stagnation

point of the cylinder, we find a

generalized velocity ‘plateau’ similar to that

of the steady-flow problem, in which all

harmonics of the free-stream oscillation may be present. Further, we determine
that,

for certain initial conditions, the boundary-layer flow develops a

finite-time singularity in the neighbourhood of the rear stagnation point.
Perturbation theory of parametrically driven

capillary waves at low viscosity
Authors: LYNGSHANSEN PER , ALSTRØM PREBEN
Published: July 2002

We present a critical review of the Hamiltonian and the Lagrangian

theories of

pattern formation in driven capillary waves at low viscosity and high aspect
ratio.

We construct a Hamiltonian perturbation theory in the spirit of Milner's
(1991)

formulation, and derive the amplitude equations and their coefficients
relevant at

the onset of surface waves. Our presentation is detailed, and we carefully
point

out the differences between our results for the nonlinear

coefficients and the results

obtained by others. From our standing wave analysis we find that the square
pattern

is subcritical. Among the supercritical standing wave patterns, we find
that the

eightfold quasi-crystalline pattern, observed by Christiansen

et al. (1992) and by

Bosch (1995), is more stable than both rolls and hexagons. We outline the

high-aspect-ratio experimental results obtained so far, and discuss them
in the

light of the theory.
Prandtl–Meyer flows with homogeneous condensation. Part 1. Subcritical
flows
Authors: DELALE C. F. , CRIGHTON D. G.
Published: July 2002

Prandtl–Meyer flows with heat addition from homogeneous condensation
not
exceeding a critical value (subcritical flows) are investigated by an asymptotic
method
in the double limit of a large nucleation time followed by a small droplet
growth
time. The physically distinct condensation zones, with detailed analytical
structure,
are displayed along streamlines and the flow field in each zone is determined
utilizing
the asymptotic solution of the rate equation along streamlines. In particular

the nucleation wave front, which corresponds to states of maximum nucleation
along
streamlines, is accurately located independently of the particular condensation
model
employed. Results obtained using the classical nucleation equation together
with the
Hertz–Knudsen droplet growth law show, despite qualitative agreement,
considerable
differences between the nucleation wave fronts and measured onset conditions
for
the experiments of Smith (1971), because of intersecting characteristics
in the heat
addition zones. This shows the necessity of including an embedded oblique
shock
wave in the expansion fan of corner expansion flows for the cases investigated.
A nonlinear critical layer generated by the
interaction of free Rossby waves
Authors: VANNESTE JACQUES
Published: July 2002

Two free waves propagating in a parallel shear flow generate a
critical layer when
their nonlinear interaction induces a perturbation whose phase velocity
matches the
basic-state velocity somewhere in the flow domain. The condition necessary
for this
to occur may be interpreted as a resonance condition for a triad formed
by the two
waves and a (singular) mode of the continuous spectrum associated with
the shear.
The formation of the critical layer is investigated in the case of freely
propagating
Rossby waves in a two-dimensional inviscid flow in a β-channel.

A weakly nonlinear analysis based on a normal-mode expansion in terms
of Rossby
waves and modes of the continuous spectrum is developed; it leads to a
system of
amplitude equations describing the evolution of the two Rossby waves and
of the
modes of the continuous spectrum excited during the interaction. The assumption
of
weak nonlinearity is not however self-consistent: it breaks down because
nonlinearity
always becomes strong within the critical layer, however small the initial
amplitudes
of the Rossby waves. This demonstrates the relevance of nonlinear critical
layers to
monotonic, stable, unforced shear flows which sustain wave propagation.

A nonlinear critical-layer theory is developed that is analogous to
the well-known
theory for forced critical layers. Differences arise because of the presence
of the Rossby
waves: the vorticity in the critical layer is advected in the cross-stream
direction by
the oscillatory velocity field due to the Rossby waves. An equation is
derived which
governs the modification of the Rossby waves that results from their interaction;
it
indicates that the two Rossby waves are undisturbed at leading order. An
analogue
of the Stewartson–Warn–Warn analytical solution is also considered.
Mass-transfer enhancement via chaotic laminar
flow within a droplet
Authors: BRYDEN MICHELLE D. , BRENNER HOWARD
Published: July 2002

The Stokes flow occurring within a non-neutrally buoyant spherical
droplet translating
by buoyancy through an immiscible liquid which is undergoing simple shear
is
shown to be chaotic under many circumstances for which the droplet translates
by
buoyancy through the entraining fluid. This flow is easily produced, for
example,
when the droplet rises (or falls) through the annular space of a vertical
concentric-cylinder Couette viscometer or through a vertical Poiseuille flow. The
parameters
studied include: (i) droplet/bulk fluid viscosity ratio; (ii) shear
strength/bubble rise
velocity ratio; and (iii) the angle between the translational bubble velocity
vector
and the vorticity vector characterizing the undisturbed shear. Streamlines
existing
within a droplet that translates perpendicular to this vorticity vector
are shown to
be non-chaotic for all choices of physical parameters. Other relative orientations

frequently contain chaotic trajectories. When solute initially dissolved
within the
droplet is extracted into the bulk fluid, the resulting overall mass-transfer
coefficient
(calculated via generalized Taylor dispersion theory) quantifying the extraction
rate at
asymptotically long times is shown to be significantly higher in the chaotic
flow case.
On solitary waves forced by underwater moving objects
Authors: ZHANG DAOHUA , CHWANG ALLEN T.
Published: July 2002

The phenomenon of a succession of upstream-advancing solitary waves generated
by underwater disturbances moving steadily with a transcritical velocity in two-
dimensional shallow water channels is investigated. The two-dimensional Navier–Stokes
(NS) equations with the complete set of viscous boundary conditions are
solved numerically by the finite-difference method to simulate the phenomenon. The
overall features of the phenomenon illustrated by the present numerical results are
unanimous with observations in nature as well as in laboratories. The relations
between amplitude and celerity, and between amplitude and period of generation of
solitary waves can be accurately simulated by the present numerical method, and
are in good agreement with predictions of theoretical formulae. The dependence of
solitary wave radiation on the blockage and on the body shape is investigated. It
furnishes collateral evidence of the experimental findings that the blockage plays a key
role in the generation of solitary waves. The amplitude increases while the period of
generation decreases as the blockage coefficient increases. It is found that in a viscous
flow the shape of an underwater object has a significant effect on the generation of
solitary waves owing to the viscous effect in the boundary layer. If a change in body
shape results in increasing the region of the viscous boundary layer, it enhances the
viscous effect and so does the disturbance forcing; therefore the amplitudes of solitary
waves increase. In addition, detailed information of the flow, such as the pressure
distribution, velocity and vorticity fields, are given by the present NS solutions.