bluuebunny/crossref_metadata_2025 huggingface dataset:
SOME INTERESTING SPECIAL CASES OF A NON-LOCAL PROBLEM MODELLING OHMIC HEATING WITH VARIABLE THERMAL CONDUCTIVITY
Authors: Tzanetis D. E. , Vlamos P. M.
Published: July 2002

The non-local equation

$$ u_t=(u^3u_x)_x+\frac{\lambda f(u)}{(\int_{-1}^1f(u)\,\rd x)^{2}} $$

is considered, subject to some initial and Dirichlet boundary conditions. Here $f$ is taken to be either $\exp(-s^4)$ or $H(1-s)$ with $H$ the Heaviside function, which are both decreasing. It is found that there exists a critical value $\lambda^*=2$, so that for $\lambda>\lambda^{*}$ there is no stationary solution and $u$ ‘blows up’ (in some sense). If $0\lt\lambda\lt\lambda^{*}$, there is a unique stationary solution which is asymptotically stable and the solution of the IBVP is global in time.

AMS 2000 Mathematics subject classification: Primary 35B30; 35B35; 35B40; 35K20; 35K55; 35K99
FORAGE PRODUCTION OF INTERCROPPED MAIZE AND SOYABEAN CULTIVARS
Authors: DE REZENDE P. M. , RAMALHO M. A. P.
Published: July 2002

Seven maize cultivars and seven soyabean cultivars were grown in monocultures, and in all possible 49 mixtures of maize and soyabean, at two locations to assess the intercropping advantages of mixtures. On average, intercrops produced 6% more dry matter and 17.5% more protein than the monocultures of maize, the most productive component. Both the dry matter and protein yields of intercrops were closely correlated with the yield of the maize component, but not with that of the soyabean component, indicating that there was no need for a specific breeding programme for maize to be used in intercropping systems. Although the average intercropping advantage, the monoculture yields of maize cultivars and, to a lesser extent, the monoculture yields of soyabean cultivars differed between locations, there was no evidence that the yield of various intercrop combinations differed between locations.
Abstracts of papers presented at the eighth Mammalian Genetics and
Development Workshop
held at the Wellcome Trust Building, Euston Road, London on 19–21
November 1997
Authors: COPP ANDREW , STEPHENSON DENNIS A.
Published: July 2002

Sponsored by: The Wellcome Trust, The Genetical Society and
B&K Universal Group Limited
Mapping quantitative trait loci in a selectively genotyped
outbred population using a mixture model approach
Authors: JOHNSON DAVID L. , JANSEN RITSERT C. , VAN ARENDONK JOHAN A. M.
Published: July 2002

A mixture model approach is employed for the mapping of quantitative
trait loci (QTL) for the
situation where individuals, in an outbred population, are selectively
genotyped. Maximum
likelihood estimation of model parameters is obtained from an Expectation-Maximization
(EM)
algorithm facilitated by Monte Carlo sampling using a Gibbs sampler. All
individuals with
phenotypes, whether genotyped or not, are included in the analysis where
both putative QTLs and
missing marker genotypes are sampled conditional on known marker information
and phenotype.
A simulation of a half-sib family structure demonstrates that this mixture
model approach will
yield unbiased estimates of the allelic effects of a QTL affecting the
trait on which selective
genotyping is based. Unbiased estimates were also obtained for the QTL
effect on a correlated
trait provided both traits were analysed jointly in a bivariate model.
The procedure is also
compared with a standard linear model approach. The application of these
methods is
demonstrated for bovine chromosome six, the data arising
from two Holstein–Friesian families
selectively genotyped for protein yield in a daughter design.
Male-specific restriction of recombination frequency in the
sex chromosomes of the medaka, Oryzias latipes
Authors: MATSUDA MASARU , SOTOYAMA SAEMI , HAMAGUCHI SATOSHI , SAKAIZUMI MITSURU
Published: July 2002

In the medaka, Oryzias latipes, the mechanism of sex determination (XX/XY) can be revealed by
genetic crosses using a body-colour gene, though it does not have cytologically recognizable sex
chromosomes. The recombination restriction of sex chromosomes in heterogametic (XY) males has
been demonstrated. To elucidate whether the recombination is prevented by the heterogamety of
the sex chromosomes or by maleness, we examined the recombination frequencies among three loci
located on the sex chromosomes (r, SL1 and SL2) in heterogametic males (XY), homogametic
males (XX and YY), homogametic females (XX) and heterogametic females (XY). The
recombination frequencies between r–SL1 and SL1–SL2
were as follows: 0, 0 (XY males); 0, 1·5
(XX males); 1·6% (YY males; 1·2%, 14·4% (XY females);
0·8%, 21·8% (XX females). These
results indicate that the recombination restriction of the sex chromosomes in heterogametic males
does not result from heterogametic sex chromosomes, but from maleness. Such sex-chromosome-
specific recombination restriction in heterogametic sex may have triggered the differentiation of sex
chromosomes in vertebrates.
Heavy heat shock induced retrotransposon transposition in Drosophila
Authors: VASILYEVA LUBOV A. , BUBENSHCHIKOVA EKATERINA V. , RATNER VADIM A.
Published: July 2002

The phenomenon of transposition induction by heavy heat shock (HHS) was studied. Males of a
Drosophila isogenic line with a mutation in the major gene radius incompletus (ri) were treated by
HHS (37 °C for 1 h followed by 4 °C for 1 h, with the cycle repeated three times) and crossed to
untreated females of the same line. The males were crossed 5 d after heat shock, and also 9 d after
HHS. Many transpositions were seen in the F1 larvae by in situ hybridization. The rate of induced
transposition was at least 2 orders of magnitude greater than that of the control sample, and was
estimated to be 0·11 events per transposable element copy per sperm. Two ‘hot’ subdivisions for
transpositions, induced probably during the post-meiotic stage of spermiogenesis, were found: 43B
and 97DE. Three-quarters of all transpositions were localized in these positions. In other sites the
rates of induced transpositions were (1·3–3·2)×10−2
events per occupied segment per sperm, 1 order of magnitude greater than those of the control.
The marine vertebrate faunas from the Late Cretaceous phosphates of Syria
Authors: BARDET N. , CAPPETTA H. , PEREDA SUBERBIOLA X. , MOUTY M. , AL MALEH A. K. , AHMAD A. M. , KHRATA O. , GANNOUM N.
Published: July 2002

Marine vertebrate faunas from the latest Cretaceous phosphates of the Palmyrides Chain of
Syria are described for the first time. Recent fieldwork in the phosphatic deposits of the Palmyra area
(mines of Charquieh and Khneifiss, outcrops of Bardeh, Soukkari and Soukhneh) have yielded a rich
and diversified assemblage of marine vertebrates, including more than 50 species of chondrichthyes,
osteichthyes, squamates, chelonians, plesiosaurians and crocodilians. Selachians are the most abundant
and diverse component of the faunas and are represented by at least 34 species of both sharks
and rays. Actinopterygians include representatives of six families, the most common being the
enchodontids. Squamates are known by six mosasaurid species and an indeterminate varanoid.
Chelonians are represented by at least two bothremydids and two chelonioids. Finally, elasmosaurid
plesiosaurs and indeterminate crocodilians are also present in the fossil assemblages. The difference in
faunal composition observed between the sites is interpreted as being due to palaeoecological preferences
related to the Hamad Uplift palaeostructure. The marine vertebrate faunas of Syria show close
affinities with those of the latest Cretaceous phosphatic deposits of North Africa and the Middle East
and are typical of the southern Tethyan realm. From a biostratigraphical point of view, the selachians
are the only suitable material to provide elements of an answer to the long debated question of the age
of the Syrian Senonian phosphates. They suggest an Early Maastrichtian age for most of the phosphates
of the Palmyrides Chain.
The sedimentology and palaeoecology of the Westleton
Member of the Norwich Crag Formation (Early Pleistocene) at
Thorington, Suffolk, England
Authors: RICHARDS A. E. , GIBBARD P. L. , PETTIT M. E.
Published: July 2002

Extensive sections in the Thorington gravel quarry complex in eastern Suffolk include the
most complete record to date of sedimentary environments of the Westleton Beds Member of the
Norwich Crag Formation. New palaeoecological and palaeomagnetic evidence is presented, which
confirms that the Member was deposited at or near a gravelly shoreline of the Crag Sea as sea level
fluctuated during a climatic ameloriation within or at the end
of the Baventian/ pre-Pastonian ‘a’ Stage
(Tiglian C4c Substage).
On the distribution of prime numbers of the form [nc]
Authors: KUMCHEV A.
Published: July 2002

Let πc(x) be the number of the integers n≤x such that [nc] is prime. We shall prove that $$π_{c}\tfrm{(}x\tfrm{)&2_Gt;}{x\over \log x}$$ for 1<c<45/38. This improves the former range 1<c<13/11.
IMPERIAL DREAMS: THE MUSSOLINI–LAVAL ACCORDS OF JANUARY 1935
Authors: STRANG G. BRUCE
Published: July 2002

The infamous January 1936 accords between Italian dictator Benito Mussolini and French foreign minister Pierre Laval have been the subject of vigorous debate. Did Laval promise Mussolini a ‘free hand’ in Ethiopia, giving tacit French approval for an Italian invasion? The two men kept no formal record of their final meeting, leaving contemporary critics and historians to speculate about their bargaining. Italian foreign ministry documents reveal the contents of the first two meetings between Mussolini and Laval. The evidence strongly indicates that Laval did give his approval for Italy to invade Ethiopia. Laval hoped to maintain limited French economic interests, but sacrificed French treaty rights in Ethiopia in order to enlist Italy in a defensive front against Germany. Laval failed to foresee the results of his diplomacy, and ended up alienating the Italian dictator.
RUMOUR, NEWS AND POPULAR POLITICAL OPINION IN ELIZABETHAN

AND EARLY STUART ENGLAND
Authors: FOX ADAM
Published: July 2002

This essay explores the circulation of rumour and news among those
at

the lower levels

of society in late sixteenth- and early seventeenth-century England. It

does so through an analysis of

the court records in which people were indicted for spreading false

reports or speaking seditious words

and which are now preserved in assize files or amid the state papers. These

sources reveal the networks

of communication by which information was disseminated nationwide and

shed light upon the

relationship between oral, manuscript and printed media. They show how

wild stories could be

whipped up in the act of transmission and were fuelled by the political

insecurities of this period. At

the same time a more sophisticated awareness of current affairs is evident

in some illicit conversations

which suggest that even humble people were participating in the arguments

which anticipated the Civil War.
WHITECHAPEL INDEPENDENTS AND THE ENGLISH REVOLUTION
Authors: LINDLEY KEITH
Published: July 2002

The existence of an Independent church at Stepney presided over
by William Greenhill
is already well known as too is the association of the eastern suburbs
generally with
religious and political radicalism in the 1640s. What is less familiar,
however, is the fact
that Stepney's neighbouring parish, St Mary Matfellon, Whitechapel,
also came to
possess an Independent church gathered under the divine Thomas Walley (or

Whalley), and that prominent members of that church and their sectarian
allies had
for some time assumed key roles in local politics and were eventually to
engineer an
Independent take-over of the parish after a protracted struggle. This article
will
focus upon the composition of the Whitechapel Independents, the form taken
by the
parochial factionalism, the identities and reactions of their local opponents
and the way
in which events and personalities in Whitechapel related to broader religious
and
political themes in the capital.
SCOTTISH OR BRITISH? POLITICS AND
POLITICAL THOUGHT IN SCOTLAND,
c. 1500–1707 The true law of kingship: concepts of monarchy in early-modern
Scotland.
By J. H. Burns.
Oxford: Clarendon Press, 1996. Pp. xiv+315. £37.50. ISBN 0-19-820384-5. Politics, religion and the British revolutions: the mind of
Samuel Rutherford. By John Coffey.
Cambridge: Cambridge University Press, 1997. Pp. xii+304. £40. ISBN
0-521-58172-9. Scots and Britons: Scottish political thought and the
Union of 1603. Edited by Roger A. Mason.
Cambridge: Cambridge University Press, 1994. Pp. xiv+323. £40. ISBN
0-521-42034-2. A Union for empire: political thought and the Union of 1707.

Edited by John Robertson
Cambridge: Cambridge University Press, 1995. Pp. xx+368. £40. ISBN
0-521-43113-1. The birth of Britain: a new nation 1700–1710. By W.
A. Speck.
Oxford: Blackwell, 1994.
Pp. xiv-235. £25. ISBN 0-521-43113-1.
Authors: BURGESS GLENN
Published: July 2002

Is the development of a new British history of the early modern
period a boon or a bane
for those interested in the history of Scotland (or, for that matter, Ireland,
Wales, even
England)? Such a false antithesis we might normally confine to our examination

papers; but it is difficult to avoid considering it after reading the five
books under review
here. Professor Burns has written a superb account of Scottish political
thought in the
long sixteenth century and Dr Coffey an equally successful exploration
of the mind of
the leading ideologist of the Covenanters. The collection edited by Dr
Mason, which
connects with the Burns study at several points, is explicitly a view of
Scottish political
thought focused on the Union of 1603, while that edited by Dr Robertson
drops the
particular emphasis on Scottish thought in its exploration of the intellectual
context to
the Union of 1707. Professor Speck presents us with a slightly different
problem: a
volume in a series on the history of early modern England that takes as
the central theme
of English politics in the decade 1700–10 the birth of Britain. Each
of these books is
rewarding, at the very least ; together their effect may be disquieting.
Pawning in German Working-Class Life Before the First World War
Authors: Fuhrer Karl Christian
Published: July 2002

This essay looks at the patterns of pawning in Germany in the decades preceding the First World War. It tries to present pawning and thus also the economy of nineteenth-century working-class households in a new light. Contrary to the generally accepted view of social historians, it is unlikely that pawning served to secure the proletarian household in periods of real hardship. There is much evidence that pawning was only considered when it seemed very likely that the borrower would be able to redeem the pledge in due course. It was therefore part of a rather stable economic situation. Insecurity of prospects persuaded people to refrain from pawning. Pawnshops thrived not on working-class destitution, but on the very modest “affluence” proletarian families were able to achieve in the era of industrialization. The striking differences between the patterns of pawning in Germany and in Great Britain therefore point to significant differences in proletarian standards of living between the two societies in question.
Effects of incorporating different amounts of straw on
growth, diseases and yield of consecutive crops of
winter wheat grown on contrasting soil types
Authors: JENKYN J. F. , CHRISTIAN D. G. , BACON E. T. G. , GUTTERIDGE R. J. , TODD A. D.
Published: July 2002

Three experiments on winter wheat, each lasting 5 years and on different soil types, were used to test
the effects of incorporating different amounts of straw, mainly to determine the importance of
achieving uniform distribution to avoid adverse effects on grain yield. Decreases in crop growth
and/or grain yield as a consequence of incorporating straw were detected in the first year. The
decreases were much larger in one experiment where straw was imported and applied to soil that had
been fallowed for 12 months before sowing the wheat than in the other two where the straw was
incorporated following the harvest of a winter wheat crop. In the subsequent 4 years, incorporating
up to 20 t straw/ha had no significant effects on grain yield but there were some significant effects on
concentrations and uptakes of N, P and K, especially on the heavier textured soils. The effects on crop
growth and yield that were detected in the first year on each site are tentatively attributed to decreases
in available N representing that which was required to support the decomposition of the incorporated
straw. The relative lack of significant effects in subsequent years seems to imply that a significant
proportion of this N was remineralized relatively quickly, and thus available to support the
decomposition of the straw that was incorporated in the second year and, after further recycling, in
the years after that. Eyespot, caused by the fungus Pseudocercosporella herpotrichoides, was decreased
by incorporating straw but there were few significant effects on other diseases. The results provide a
generally reassuring message for farmers in suggesting that on most, if not all, soils there is little cause
for concern about the consequences of incorporating even large amounts of wheat straw before
sowing a further crop of winter wheat.
The evaluation of dual-purpose groundnut (Arachis hypogaea) varieties for fodder and seed production at Shika, Nigeria
Authors: OMOKANYE A. T. , ONIFADE O. S. , OLORUNJU P. E. , ADAMU A. M. , TANKO R. J. , BALOGUN R. O.
Published: July 2002

At Shika in a subhumid environment of Nigeria, a 3-year study was carried out to select newly
developed groundnut varieties for use in crop–livestock production systems. The study examined 11
groundnut varieties. Emergence time, plant stands at full emergence, forage and seed yields and yield
components were examined. Whole plant samples were analysed for crude protein (CP) content.
Varieties ICGV 87123 gave the lowest forage yield and cultivar M517-80I, the highest, with seven
varieties recording forage yields above 5 t/ha. The CP content of forage was lowest (14·8%) for
variety M576-80I and highest (21·6%) for variety M554-76. Mean seed yield (over 3 years) varied
significantly from 0·73 to 1·68 t/ha. Only two varieties had mean seed yield >1 t/ha. The relationship
between seed and forage yields was positive and significant (r = 0·529, P < 0·006). Varieties RMP 12,
88-80I and M517–80 were most promising for both forage and seed production.
Effect of air temperature and energy intake on body mass, body composition and energy requirements in sheep
Authors: ALLAN DEGEN A. , YOUNG B. A.
Published: July 2002

Body mass was measured and body composition and energy requirements were estimated in sheep at four air temperatures (0 °C to 30 °C) and at four levels of energy offered (4715 to 11785 kJ/day) at a time when the sheep reached a constant body mass. Final body mass was affected mainly by metabolizable energy intake and, to a lesser extent, by air temperature, whereas maintenance requirements were affected mainly by air temperature. Mean energy requirements were similar and lowest at 20 °C and 30 °C (407·5 and 410·5 kJ/kg0·75, respectively) and increased with a decrease in air temperature (528·8 kJ/kg0·75 at 10 °C and 713·3 kJ/kg0·75 at 0 °C). Absolute total body water volume was related positively to metabolizable energy intake and to air temperature. Absolute fat, protein and ash contents were all affected positively by metabolizable energy intake and tended to be related positively to air temperature. In proportion to body mass, total body water volume decreased with an increase in metabolizable energy intake and with an increase in air temperature. Proportionate fat content increased with an increase in metabolizable energy intake and tended to increase with an increase in air temperature. In contrast, proportionate protein content decreased with an increase in metabolizable energy intake and tended to decrease with an increase in air temperature. In all cases, the multiple linear regression using both air temperature and metabolizable energy intake improved the fit over the simple linear regressions of either air temperature or metabolizable energy intake and lowered the standard error of the estimate. The fit was further improved and the standard error of the estimate was further lowered using a polynomial model with both independent variables to fit the data, since there was little change in the measurements between 20 °C and 30 °C, as both air temperatures were most likely within the thermal neutral zone of the sheep. It was concluded that total body energy content, total body water volume, fat and protein content of sheep of the same body mass differed or tended to differ when kept at different air temperatures.
Effects of 28-homobrassinolide on yields of wheat, rice,
groundnut, mustard, potato and cotton
Authors: RAMRAJ V. M. , VYAS B. N. , GODREJ N. B. , MISTRY K. B. , SWAMI B. N. , SINGH N.
Published: July 2002

Yield responses of some economically important crop plants due to
foliar applications of low
concentrations of 28-homobrassinolide (HBR) were studied in experiments
conducted at research
stations and in farmers' fields in India during 1989–95. Foliar
sprays of different concentrations of
HBR were applied at tillering and spike/panicle initiation in wheat
(0·5 and 1·0 mg/l) and rice (0·25,
0·50 and 1·00 mg/l); at flowering and pegging in groundnut
(0·25 and 0·50 mg/l); 30 and 45 days after
sowing (DAS) in mustard (0·25 and 0·50 mg/l); 25 and 35 days
after emergence in potato (0·25 and
0·50 mg/l); and 30, 50, 70 DAS in cotton (0·1 and 1·0
mg/l). The HBR treatments significantly (P<0·05 and
P<0·01) increased grain yields in wheat, rice and mustard,
pod yields in groundnut, tuber
yields in potato and seed cotton yields, over control. The extent of yield
improvement due to HBR
was influenced by crop species, concentration of HBR, plant growth stage at
application and frequency of application.
Effect of maize supplementation, seasonal temperature

and humidity on the liveweight gain of steers grazing

irrigated Leucaena leucocephala/Digitaria eriantha

pastures in north-west Australia
Authors: PETTY S. R. , POPPI D. P. , TRIGLONE T.
Published: July 2002

Brahman Shorthorn steers (213±4·6 kg

initial weight) were grazed on a pangola (Digitaria

eriantha cv. Steudel) pasture interplanted with leucaena

(Leucaena leucocephala cv. Cunningham) in rows

1·8–2·7 m apart in the Ord River

Irrigation Area (ORIA) in north-west Western Australia. The

leucaena comprised a mean of 46% of the diet but ranged

from 100% of the diet on day 1 to c. 18%

on day 7 of a 7-day grazing period, within the rotational

grazing system. It was suggested that the

low herbage allowance of leucaena may have restricted the

intake of the steers, reducing the quantity

and quality of the herbage consumed.

The steers were also supplemented with maize during the

dry and wet seasons (1992 and 1992/93).

The maize supplement was offered at 0, 0·5,

1·0, 1·5 and 2·0 kg/head per day,

over a 168-day period.

Maize supplementation at 1·5 kg maize per head per

day resulted in an increase in the liveweight gain

of the steers grazing leucaena/pangola pastures in the

dry season from 0·73±0·05 kg/day

(mean±S.E.) for no supplementation to

1·1±0·05 kg/day for

1·5 kg/head per day of maize. Maize

supplementation up to 2·0 kg/day did not

further increase the liveweight gain. A high rate of

substitution of leucaena and pangola intake for the maize

supplement occurred.

There was a large seasonal difference in liveweight gain

(mean 0·89 v. 0·63 kg/day for the dry and

wet seasons respectively; P<0·001)

irrespective of the level of maize supplementation. This seasonal

difference in liveweight gain was not primarily a

function of the herbage on offer, but was most

probably a direct function of the effect of the seasonal

temperature and humidity influencing the feed

intake and growth rate of these Brahman crossbred cattle.

This system produced some of the higher liveweight gains

recorded per hectare for a grazing system

(1570–2110 kg/ha per year), as a result of the

very good individual liveweight gains (250-340 kg/head

per year) and high stocking rate (6·25 head/ha).
Selective grazing in pure leaf and leaf/culm mixtures
of herbage grasses by sheep
Authors: HONGO A.
Published: July 2002

Five grazing trials using Suffolk wethers were carried out at Obihiro,
Japan from June to July of 1989
and 1990. New methodology was developed to investigate bite weight and
bite selection using hand-constructed swards, which were composed of 128 points of plant units spaced
4 cm apart. Leaves and
reproductive culms of orchardgrass (Dactylis glomerata) and timothy
(Phleum pratense) were used in
five kinds of artificial swards (three pure leaf mixtures and two leaf/culm
mixtures).

In the leaf/culm mixture, sheep definitely selected leaf units.
The inclusion of reproductive culms
decreased the number of prehending bites and the total distance of travel
between bites. Mean
distance of travel between bites was 8·6–10·6 cm. Mean
travelling speed was 7·2 cm/s and was not
influenced by the inclusion of culms. Total distance of travel between
bites was 3·8–4·1 m/min in pure
leaf mixtures and 3·4–3·5 m/min in leaf/culm
mixtures.

The actual area covered by one prehending bite, estimated from direct
measurement, was
21–27 cm2 in pure leaf mixtures and 15–16 cm2

in leaf/culm mixtures. Decreased bite area in leaf/culm mixtures
resulted in decreased bite weight and intake rate. Experimental errors
observed were
discussed with respect to the biting behaviour of sheep and flexibility
of grass leaves.
Effects of nitrogen fertilizer on the grain yield and
quality of winter oats
Authors: CHALMERS A. G. , DYER C. J. , SYLVESTER-BRADLEY R.
Published: July 2002

Amounts of spring nitrogen (N) fertilizer (0–240 kg/ha),
combined with three timing treatments
(single, divided early or divided late), were tested at 14 sites in England
and Wales between 1984 and
1988 to determine the optimum fertilizer N requirement for winter oats.
The trials were superimposed
on commercial crops of the cultivars Pennal (9 sites) or Peniarth (5 sites).
Optimum amounts of N
ranged from nil to 202 kg/ha (mean 119) and optimum yields varied between
5·8 and 9·9 t/ha (mean
7·3). Much (c. 60%) of the inter-site variation in N optimum
was explained by differences in soil N
supply, as indicated by N offtake in the grain at nil applied N. Mean yield
differences between single
and early (+0·08 t/ha) or late (−0·04 t/ha)
divided dressings were slight, although significant
(P<0·05) but inconsistent yield effects were obtained
from early N at two sites and late N at three sites.

Lodging occurred at 11 of the 12 sites where lodging scores were recorded
and always increased
significantly (P<0·05) with applied N. The amount of
crop lodging at N optimum was, on an area
basis, <50% at nine of the sites. The overall extent of site lodging
was also influenced by soil N
fertility and hence inversely related to N optimum. However, multiple regression,
using site lodging
as well as soil N supply, only accounted for slightly more (65%) of the
variation in N optimum, which
suggests that lodging was not a major limiting factor. Lodging was unexpectedly
less from early N
(mean 43%), but more from late N (53%) divided dressings, compared with
a single N dressing
(49%). Early N reduced lodging significantly (P<0·05)
at four sites, although the actual reduction
was only large at one site where early N also increased yield significantly
(+0·57 t/ha).

Grain N concentrations increased significantly (P<0·05)
with applied N, on average by 0·12% per
40 kg/ha N increment. Timing effects on grain N concentration were
very small, with mean values
of 1·94, 1·91 and 1·96%N respectively from single,
early and late divided dressings. Apparent
recovery in grain of fertilizer N at the optimum amount ranged from 13
to 57% (mean 37), with better
N recovery at the more yield-responsive sites. Changes in mean grain weight
due to the amount and
timing of fertilizer N were small, with an average reduction of 0·6
mg/grain per 40 kg/ha N applied.
The adverse effects of N fertilizer on grain quality were slight and unlikely
to have commercial
significance. The agronomic implications of these results on the N fertilization
of winter oats are
discussed.
Nitrogen mass balance in deep litter during the pig fattening cycle and during composting
Authors: MØLLER H. B. , SOMMER S. G. , ANDERSEN B. H.
Published: July 2002

For welfare reasons, fattening pigs on organic farms are raised on deep litter in the open with simple,
flexible climate tents for shelter. Within this system, the nitrogen (N) flow both during fattening of
the pigs from 17 to 100 kg liveweight in winter and during composting of the deep litter from the
enclosures in summer was studied. During the fattening period, the pigs were provided with barley
straw at four daily rates (0·67, 1·21, 1·32 and 1·87 kg) per kg increase in liveweight. During the summer
period, N balances from four enclosures receiving straw at around the 1·32 kg rate were examined.
Temperatures in the deep litter mat and in the compost heap were determined, as well as
concentrations of ammonia (NH3) and nitrous oxide (N2O) in the compost heaps. The temperature
increased after 4 weeks to between 40 and 70 °C in the deep litter mats receiving > 1·21 kg straw; the
highest temperatures were observed in the mats with the highest straw rate. Temperatures exceeded
50 °C in all compost heaps. In the deep litter mats and compost heaps the highest temperatures were
recorded for the longest periods in the material containing the most straw. The initial concentration
of NH3 in the gas phase of the compost heaps was > 10 mg NH3-N/m3, which dropped to zero within
1 month. After the NH3 concentration had fallen, the amount of N2O increased significantly for a
period in the two heaps with 1·21 and 1·32 kg straw. Over 120 days in summer, an average of
16·3±6% N was lost from the four enclosures strawed at a rate of 1·32 kg (±0·2 kg) straw per kg
increase in liveweight. During the winter 12–24% of the N excreted was lost during a fattening period
of 119–134 days, and 15–42% of the N stored was lost during the following composting period of
143 days. In total, 29–54% of the N added to the deep litter mat in excretion and straw was lost
during the fattening period (119–134 days) and subsequent storage (143 days). The lowest loss was
recorded from deep litter strawed daily with 1·32 kg straw per kg increase in pig liveweight.
Effect of plant arrangement pattern and irrigation on efficiency of maize (Zea mays) and bean (Phaseolus vulgaris) intercropping system
Authors: OLJACA S. , CVETKOVIC R. , KOVACEVIC D. , VASIC G. , MOMIROVIC N.
Published: July 2002

A field study was conducted on an experimental field of the Maize Research Institute Zemun Polje-
Belgrade (latitude: 44° 49′ N), Yugoslavia over a 3 year period (1994–1996). The objective of this
study was to find the optimal spatial arrangement of a maize–beans intercrop in irrigated and rainfed
farming systems.

Plant arrangement patterns in an intercropping system did not significantly affect LAI values in
maize compared with a sole crop, while irrigation had a greater positive influence on it. Leaf area
values of beans were more sensitive to the same treatments. Microenvironmental conditions in
maize–bean mixtures were more favourable for bean crop than for sole beans.

An intercropping system had a greater influence on yield components of maize. Component
combination 1/2[ratio ]1/2 (maize[ratio ]bean) was most effective in all yield components of maize. Intraspecific
competition appears to be more intense than interspecific competition in both crops. Yield
component of bean was more sensitive to water regime of the site than to planting pattern in an
intercrop. Irrigation increased all yield components of bean (especially pod number). The
intercropping system decreased harvest index in both crops compared with monocrops. Maximum
total grain yield was in 1994 in irrigated maize–bean intercrop 1/2[ratio ]1/2, with highest efficiency being
in an intercrop in irrigation in 1995. The Land Equivalent Ratio (LER), based on grain yield, was
consistently greater than 1·0 in an irrigation water regime in 1995. Proportion of maize[ratio ]bean
= 1/2[ratio ]1/2 gave the highest increase of yield (LER = 1·54). Under conditions of chernozem soil type in
Zemun Polje, with often-expressed dry periods, irrigation is a very important measure for increasing
maize–beans intercrop productivity.
Race and Representation in the
United States: the Constitutional
Validity of Majority–Minority
Congressional Districts
Authors: McKEEVER ROBERT J.
Published: July 2002

In an effort to maximize the representation of African Americans and
Hispanics in the United States House of Representatives, many state
legislatures have consciously sought to create so-called
“majority–minority” congressional districts.
This involves carving out districts in
which African Americans or Hispanics constitute more than 50 per cent
of the voting age population. The expectation is that such districts will
elect a minority member of the House, which in turn will lead to a
Congress that is more sensitive and responsive to the needs and interests
of America's two largest ethnic minorities. Indeed, this expectation has
become an article of faith for the mainstream civil rights movement and
its white sympathizers.

However, like other forms of affirmative action, majority–minority
districting sits rather uncomfortably alongside the Constitutional principle
of race-neutrality. In a series of recent cases, the United States Supreme
Court has declared that, by subordinating traditional districting principles
to the overriding need to draw boundaries along racial lines, states have
violated the Equal Protection clause of the Fourteenth Amendment.
THE IMPACT OF SOCIAL STATUS AND MIGRATION ON FEMALE AGE AT MARRIAGE IN AN HISTORICAL POPULATION IN NORTH-WEST GERMANY
Authors: VOLAND E. , DUNBAR R. I. M.
Published: July 2002

It has been suggested that parish-based reconstitution studies may underestimate the true age at marriage because they do not normally include data for emigrants who may be expected to behave differently from individuals who remain in their natal parishes. This study uses data from C18-19th parish registers of north-west Germany to estimate the difference in age at marriage between leavers and stayers. The difference is not significant for males; although that for females is significant, it is small and the consequence of failing to include migrants is likely to be negligible for most studies. However, it is shown that there is also an independent effect on age at marriage that is due to the woman's natal social (economic) status; historical demographic studies that ignore this dimension may risk confounding two different effects.
INSURANCE OVULATION, EMBRYO MORTALITY AND TWINNING
Authors: BALL HELEN L. , HILL CATHERINE M.
Published: July 2002

The ‘insurance ova’ hypothesis (Anderson, 1990) views dizygotic twinning as a by-product of selection for multiple ovulation which sometimes – in error – results in the birth of twins. From this viewpoint, polyovulation is a mechanism which reduces the risks of fertilization failure or embryo defect/mortality. If DZ twin births are a ‘side-effect’ of a mechanism which compensates for defective embryos one might predict that embryo defect rates and twinning rates will covary. This prediction is tested using national-level data on twinning rates and rates of trisomy-21 (Down's syndrome), and a strong positive correlation is found, even when controlling for maternal age. One suggestion that follows from this finding is that intra- and interpopulation variation in both twinning rates and Down's syndrome rates may result, in part, from individual variation in pre-implantation rejection of embryos in the very early stages of pregnancy. In this paper it is proposed that the ‘insurance ova’ explanation for twinning in humans could be expanded to incorporate a model of rejection of anomalous embryos, be they anomalies of number or type. Variation in the efficiency of an embryo rejection mechanism, combined with variation in frequency of polyovulation, would have consequences for individual reproductive success.
Changes in electrical conductivity and somatic cell count between

milk fractions from quarters subclinically infected with particular mastitis
pathogens
Authors: WOOLFORD MURRAY W. , WILLIAMSON JOHN H. , HENDERSON HAROLD V.
Published: July 2002

Cows with subclinical intramammary infections were identified by
milk
bacteriology. The mastitis pathogens included Staphylococcus aureus

(n=9), Streptococcus uberis (n=10) and
coagulase-negative staphylococci (n=10). Samples
of first fore milk, main flow milk and strippings milk fractions were collected
from
each quarter and laboratory measurements were made of electrical conductivity,

milk fat concentration and somatic cell count. Conductivity measurements
were
corrected for milk fat concentration and within-cow inter-quarter conductivity

ratios calculated. Repeatability estimates of all measurements between
days were
calculated. In the case of infected quarters, all conductivity values decreased

markedly (P<0·05) from first fore milk to
main flow milk fractions. Conductivity
differences between quarters of infected cows were substantially lower
during the
main milk flow phase. For quarters infected with Staph. aureus
an increase in
conductivity was observed (P<0·05) from
main flow to strippings fractions. For
uninfected quarters, conductivity declined as milk fat concentration increased
with
successive milk fractions. Variation, both within and between milk fractions,
was
greater for somatic cell count than for conductivity. Differences in conductivity

between milk fractions from individual infected quarters were not accounted
for by
changes in fat concentration and may result from the mixing of milk from
infected
and uninfected regions of the gland. Localized infection may produce a
decrease in
conductivity between fore milk and mid-flow fractions while differential
drainage
from an infection site in the secretory tissue may additionally produce
an increase in
conductivity from mid-flow to strippings fractions. Such changes may thus
provide
information on the location and magnitude of an infection. The results
clearly
demonstrate the importance of the milk fraction when using conductivity
as a
diagnostic of intramammary infection, the highest diagnostic sensitivity
being
achieved by using first fore milk samples.
Multiple forms of lactadherin (breast antigen BA46) and
butyrophilin are secreted into human milk as major components of
milk fat globule membrane
Authors: CAVALETTO MARIA , GIUFFRIDA MARIA G. , GIUNTA CARLO , VELLANO CAMILLO , FABRIS CLAUDIO , BERTINO ENRICO , GODOVAC-ZIMMERMANN JASMINKA , CONTI AMEDEO
Published: July 2002

In the lactating mammary gland, epithelial cells secrete triacylglycerols in the
form of droplets enveloped by an apical surface membrane. This membrane is known
as the milk fat globule membrane (MFGM; Mather & Keenan, 1983). MFGM-associated
proteins have been studied and employed in developing antibodies against
surface antigens of breast epithelial cells, which are used in breast cancer
immunodiagnosis and histopathology (Salinas et al. 1987; Larocca et al. 1991;
Peterson et al. 1995). So far, only a small number of proteins have been analysed and
their sequence identified in bovine, murine and human MFGM; among them are
butyrophilin (Jack & Mather, 1990; Ishii et al. 1995;
Taylor et al. 1996), MFG-E8 (Stubbs et al. 1990),
PAS 6/7 (Hvarregaard et al. 1996) and lactadherin or breast
antigen BA46 (Couto et al. 1996; Taylor et al. 1997).
Several minor proteins have yet
to be characterized, since it is not easy to isolate them in large quantities from the
membrane. SDS gel patterns give useful information about MFGM proteins, such as
concentration, relative molecular mass and presence of carbohydrate. Over forty
membrane components have been separated by electrophoretic techniques from
bovine MFGM (Mather et al. 1980).

The research reported here combined SDS-PAGE with sequencing analysis and
describes the composition of human MFGM, with the exception of high molecular
mass mucin, which only penetrates an acrylamide gel of 40 g/l. Mucins have been
extensively studied and the sequence predicted from cDNA (Gendler et al. 1990).
Surprisingly, identification of the protein bands in the present study revealed that
three proteins alone constituted the major components of human MFGM: xanthine
oxidase (EC 1.1.3.22), butyrophilin and lactadherin. Lactadherin belongs to a family
of proteins possessing epidermal growth factor-like and factor V/VIII C1/C2-like
domains, including bovine PAS 6/7, guinea pig GP55 (Hvarregaard et al. 1996) and
murine MFG-E8 (Stubbs et al. 1990). In a previous investigation, we characterized
lactadherin (formerly breast antigen BA46) and its truncated 30 kDa form as
components of healthy human MFGM (Giuffrida et al. 1998). Human butyrophilin
has recently been cloned and sequenced (Taylor et al. 1996); the presence of two
extracellular immunoglobulin superfamily domains suggested a potential cell surface
receptor function. This study was aimed at identifying and characterizing the
multiple forms of the major proteins of MFGM.
Direct numerical simulation of a supersonic turbulent boundary layer at Mach 2.5
Authors: GUARINI STEPHEN E. , MOSER ROBERT D. , SHARIFF KARIM , WRAY ALAN
Published: July 2002

A direct numerical simulation of a supersonic turbulent boundary layer has been
performed. We take advantage of a technique developed by Spalart for incompressible
flow. In this technique, it is assumed that the boundary layer grows so slowly
in the streamwise direction that the turbulence can be treated as approximately
homogeneous in this direction. The slow growth is accounted for by a coordinate
transformation and a multiple-scale analysis. The result is a modified system of
equations, in which the flow is homogeneous in both the streamwise and spanwise
directions, and which represents the state of the boundary layer at a given streamwise
location. The equations are solved using a mixed Fourier and B-spline Galerkin
method.

Results are presented for a case having an adiabatic wall, a Mach number of
M = 2.5, and a Reynolds number, based on momentum integral thickness and wall
viscosity, of Reθ′ = 849. The Reynolds number based on momentum integral thickness
and free-stream viscosity is Reθ = 1577. The results indicate that the Van Driest
transformed velocity satisfies the incompressible scalings and a small logarithmic
region is obtained. Both turbulence intensities and the Reynolds shear stress compare
well with the incompressible simulations of Spalart when scaled by mean density.
Pressure fluctuations are higher than in incompressible flow. Morkovin's prediction
that streamwise velocity and temperature fluctuations should be anti-correlated, which
happens to be supported by compressible experiments, does not hold in the simulation.
Instead, a relationship is found between the rates of turbulent heat and momentum
transfer. The turbulent kinetic energy budget is computed and compared with the
budgets from Spalart's incompressible simulations.
Vortex dynamics and entrainment in rectangular free jets
Authors: GRINSTEIN FERNANDO F.
Published: July 2002

Simulations of low-aspect-ratio, rectangular free jets are presented. The investigations
focus on the entrainment and transitional vortex dynamics in compressible (subsonic)
jets initialized with laminar conditions, a thin vortex sheet with slightly rounded-off
corner regions, and uniform initial momentum thickness. A monotonically integrated
large-eddy simulation approach based on the solution of the unsteady flow equations
with high-resolution monotone algorithms is used. Inherent uncertainties in the jet
entrainment measurement process are addressed using the database from laboratory
experiments and simulations. Vorticity geometries characterizing the near flow field
of low aspect-ratio (A) rectangular jets are demonstrated, involving: (i) self-deforming
and (ii) splitting vortex rings; interacting ring and braid (rib) vortices including (iii)
single ribs aligned with corner regions (A [ges ] 2) and (iv) rib pairs aligned with the
corners (A = 1); (v) a more disorganized flow regime in the far jet downstream, where
the rotational-fluid volume is occupied by a relatively weak vorticity background with
strong, slender tube-like filament vortices filling a small fraction of the domain – as
observed in fully developed turbulent flows. The near field entrainment properties
of low-A rectangular jets are shown to be largely determined by the characteristic
A-dependent coupling geometry of interacting rib and ring vortices and by vortex-ring
axis-switching times.
Displacement of fluid droplets from solid

surfaces in low-Reynolds-number shear flows
Authors: DIMITRAKOPOULOS P. , HIGDON J. J. L.
Published: July 2002

The yield conditions for the displacement of fluid droplets from
solid

boundaries are

studied through a series of numerical computations. The study includes
gravitational

and interfacial forces, but is restricted to two-dimensional droplets and

low-Reynolds-number flow. A comprehensive study is conducted, covering
a wide

range of viscosity

ratio λ, Bond number Bd, capillary
number

Ca and contact angles θA and

θR. The

yield conditions for drop displacement are calculated and the critical
shear

rates are presented as functions

Ca(λ, Bd, θA,

Δθ) where

Δθ=θA−θR
is

the contact angle hysteresis. The numerical

solutions are based on the spectral boundary element method, incorporating
a

novel implementation of Newton's method for the determination of

equilibrium free surface profiles. The numerical results are compared with

asymptotic theories (Dussan 1987) based on the lubrication approximation.

While excellent agreement is found in the joint asymptotic limits

Δθ[Lt ]θA[Lt ]1,

the useful range of

the lubrication models proves to be extremely limited. The critical shear
rate

is found

to be sensitive to viscosity ratio with qualitatively different results
for

viscous and

inviscid droplets. Gravitational forces normal to the solid boundary have
a

significant

effect on the displacement process, reducing the critical shear rate for

viscous drops

and increasing the rate for inviscid droplets. The low-viscosity limit

λ→0 is shown

to be a singular limit in the lubrication theory, and the proper scaling
for

Ca at small λ is identified.
Finite-amplitude equilibrium states in plane Couette flow
Authors: CHERHABILI A. , EHRENSTEIN U.
Published: July 2002

A numerical bifurcation study in plane Couette flow is performed
by computing

successive finite-amplitude equilibrium states, solutions of the

Navier–Stokes equations. Plane Couette flow being linearly

stable for all Reynolds numbers, first two-dimensional equilibrium

states are computed by extending nonlinear travelling waves

in plane Poiseuille flow through the Poiseuille–Couette flow

family to the plane

Couette flow limit. The resulting nonlinear states are stationary with
a spatially

localized structure; they are subject to two-dimensional and three-dimensional

secondary disturbances. Three-dimensional disturbances dominate the dynamics
and

three-dimensional stationary equilibrium states bifurcating at criticality

on the two-dimensional equilibrium surface are computed. These nonlinear

states, periodic in the

spanwise direction and spatially localized in the streamwise direction,

are computed for

Reynolds numbers (based on half the velocity difference between the

walls and channel

half-width) close to 1000. While a possible relationship between the computed

solutions and experimentally observed coherent structures in turbulent
plane Couette

flow has to be assessed, the present findings reinforce the

idea that subcritical transition

may be related to the existence of finite-amplitude states which

are (unstable) fixed

points in a dynamical systems formulation of the Navier–Stokes system.