bluuebunny/crossref_metadata_2025 huggingface dataset:
Necheminių piktžolių kontrolės būdų efektyvumo palyginimas vasarinių rapsų pasėlyje ekologinės žemdirbystės sąlygomis
Authors: Velička Rimantas , Mockevičienė Rita , Marcinkevičienė Aušra , Pupalienė Rita , Butkevičienė Lina Marija , Kriaučiūnienė Zita , Kosteckas Robertas , Čekanauskas Sigitas
Published: December 2015

Rapsų auginimo ekologinėje žemdirbystės sistemoje tyrimų pasaulyje atlikta nemažai, tačiau Lietuvos klimatinėmis sąlygomis jų trūksta, ypač taikant pažangias piktžolių kontrolės priemones. Lauko eksperimentas atliktas 2013–2014  m. Aleksandro Stulginskio universiteto Bandymų stotyje. Dirvožemis – giliau glėjiškas išplautžemis (Endohypogleyic Luvisol). Tyrimų tikslas – įvertinti necheminių piktžolių kontrolės būdų efektyvumą vasarinių rapsų pasėlio piktžolėtumui bei sėklų derlingumui ekologinės žemdirbystės sąlygomis. Eksperimento variantai: necheminiai piktžolių kontrolės būdai: 1) terminis (drėgnuoju vandens garu); 2) mechaninis (tarpueilių purenimas); 3) savireguliacija (stelbimas). Pavasarį vasarinių rapsų pasėlyje vyravo baltoji balanda, raudonžiedė notrelė ir daržinė žliūgė. Mechaniniam piktžolių naikinimui jautriausia buvo baltoji balanda, o terminiam – raudonžiedė notrelė ir daržinė žliūgė. Piktžolių daigų skaičius esmingai mažėjo taikant terminį (nuo 1,5 iki 1,8 karto) bei mechaninį (nuo 2,5 iki 6,8 karto) piktžolių kontrolės būdus vasarinių rapsų pasėlyje, palyginti su savireguliacija. Efektyviausias piktžolių kontrolės būdas ekologiškai auginamų rapsų pasėlyje buvo mechaninis (efektyvumas 30,9–75,5  %). Terminio piktžolių kontrolės būdo efektyvumas, palyginti su mechaniniu, buvo mažesnis (28,4–40,0 %). Prieš nuimant derlių rapsų pasėlyje, kur taikytas mechaninis piktžolių naikinimas, palyginti su savireguliacija, piktžolių skaičius buvo esmingai mažesnis 3,2–4,4 karto, piktžolių sausųjų medžiagų masė  –  2,2–3,1  karto. Auginant vasarinius rapsus ekologinės gamybos ūkiuose efektyviau taikyti mechaninį piktžolių kontrolės būdą nei terminį, nes vidutinis rapsų sėklų derlingumas gaunamas 15,8 % didesnis. Vasarinių rapsų derlingumas priklausė nuo piktžolių daigų skaičiaus prieš panaudojant kontrolės būdus (r = –0,99, r < 0,05) ir piktžolių sausųjų medžiagų masės – prieš nuimant derlių (r = –0,99, r < 0,05).
Ūkių žemės naudojimo perspektyvos Lietuvoje
Authors: Stravinskienė Vaiva , Aleknavičius Audrius , Aleknavičius Pranas
Published: December 2015

Straipsnyje nagrinėjamos Lietuvos kaimo plėtros 2007–2013  m. programos įgyvendinimo pasekmės žemės ūkio paskirties žemės naudojimui. Pagrindinis tyrimų tikslas  –  išanalizuoti žemės ūkio naudmenų ploto pokyčius ir galimybes reguliuoti žemės ūkio raidą šalies regionuose. Analizės pagrindu nustatyti prognozuojami žemės ūkio naudmenų ploto, ūkio dydžio ir žemės ūkio gamybos specializacijos pokyčiai iki 2020  metų. Pateikti pasiūlymai teisinėmis ir ekonominėmis priemonėmis reguliuoti agrarinių teritorijų plėtrą šalies savivaldybėse taip, kad būtų išsaugotas ir padidintas našių žemės ūkio naudmenų plotas, o augalininkystės ir gyvulininkystės gamybos šakos būtų plėtojamos atsižvelgiant į tinkamiausią žemės ūkinių savybių panaudojimą. Padidinus žemės naudojimo efektyvumą ir teikiant Europos Sąjungos bei valstybės paramą, šalyje gali didėti deklaruojamų žemės ūkio naudmenų plotas (apie 5 %), vidutinis ūkio dydis (iki 29,5 ha), intensyviųjų kultūrų pasėlių plotas (11 % ir daugiau). Dėl racionalesnio daugiamečių žalienų naudojimo sutartinių galvijų skaičių šalyje galima padidinti 58 % ir daugiau.
Influência da modificação do teste de sentar e alcançar sobre o indicador de flexibilidade em diferentes faixas etárias
Authors: Bezerra Ewertton De Souza , Martins Sandro Lemos , Leite Thalita Batista , Paladino Kayo Douglas Vieira , Rossato Mateus , Simão Roberto
Published: December 2015

O objetivo do presente estudo foi comparar a influência do Teste de Sentar e Alcançar (TSA) modificado com e sem aquecimento sobre o score final obtido por diferentes faixas etárias de homens e mulheres fisicamente ativos. A amostra foi composta por 412 sujeitos, sendo 321 do gênero feminino (45 ± 14,09 anos; 66 ± 12,23Kg; 1,55 ± 0,05m) e 91 do gênero masculino (42 ± 15,75 anos; 74,6 ± 12,41Kg; 1,65 ± 0,07m). Todos os indivíduos realizaram o TSA modificado e convencional, com e sem aquecimento. O TSA modificado apresentou resultados significativos quando comparado à forma convencional, em ambos os gêneros avaliados (p = 0,0001). Em relação à condição para realizar o teste (com e sem aquecimento), o protocolo com aquecimento foi superior ao protocolo sem aquecimento, em ambos os gêneros, para o TSA modificado e convencional (p = 0,0001). Como conclusão, para avaliar a flexibilidade de membros inferiores, seria interessante utilizar um TSA adaptado, a fim de minimizar uma possível influência no score obtido no final do teste.
Propriedades psicométricas da versão brasileira do Physical Education Teaching Processes Questionnaire
Authors: Fernandes Marcos Gimenes , Nunes Sandra Adriana Neves , Silva Gidafle Gama , Fernandes Helder Miguel
Published: December 2015

O presente estudo teve como objetivos: i) traduzir e adaptar para o contexto brasileiro (equivalência semântica/conceitual e validade de conteúdo) o Physical Education Teaching Processes Questionnaire; e  ii) verificar as suas propriedades psicométricas (confiabilidade e validade fatorial). A amostra foi composta por 301 alunos (140 do sexo masculino e 161 do sexo feminino) de dua escolas públicas da Bahia, com idades compreendidas entre 12 e 18 anos (M = 16.35; DP = 1.73). A consistência interna e validade fatorial do instrumento foram analisadas através do alpha de Cronbach e análise fatorial confirmatória (AFC), respectivamente. A confiabilidade dos fatores variou entre .54 e .78. Os resultados da AFC indicaram que a versão original (20 itens e 6 fatores) do Physical Education Teaching Processes Questionnaire revelou uma boa adequação estrutural. Estes resultados sugerem que a versão brasileira deste instrumento possui propriedades psicométricas adequadas para ser utilizado no contexto escolar brasileiro.
Observation of long-range tertiary interactions during ligand binding by the TPP riboswitch aptamer
Authors: Duesterberg Van K , Fischer-Hwang Irena T , Perez Christian F , Hogan Daniel W , Block Steven M
Published: December 2015

The thiamine pyrophosphate (TPP) riboswitch is a cis-regulatory element in mRNA that modifies gene expression in response to TPP concentration. Its specificity is dependent upon conformational changes that take place within its aptamer domain. Here, the role of tertiary interactions in ligand binding was studied at the single-molecule level by combined force spectroscopy and Förster resonance energy transfer (smFRET), using an optical trap equipped for simultaneous smFRET. The ‘Force-FRET’ approach directly probes secondary and tertiary structural changes during folding, including events associated with binding. Concurrent transitions observed in smFRET signals and RNA extension revealed differences in helix-arm orientation between two previously-identified ligand-binding states that had been undetectable by spectroscopy alone. Our results show that the weaker binding state is able to bind to TPP, but is unable to form a tertiary docking interaction that completes the binding process. Long-range tertiary interactions stabilize global riboswitch structure and confer increased ligand specificity.
COPI selectively drives maturation of the early Golgi
Authors: Papanikou Effrosyni , Day Kasey J , Austin Jotham , Glick Benjamin S
Published: December 2015

COPI coated vesicles carry material between Golgi compartments, but the role of COPI in the secretory pathway has been ambiguous. Previous studies of thermosensitive yeast COPI mutants yielded the surprising conclusion that COPI was dispensable both for the secretion of certain proteins and for Golgi cisternal maturation. To revisit these issues, we optimized the anchor-away method, which allows peripheral membrane proteins such as COPI to be sequestered rapidly by adding rapamycin. Video fluorescence microscopy revealed that COPI inactivation causes an early Golgi protein to remain in place while late Golgi proteins undergo cycles of arrival and departure. These dynamics generate partially functional hybrid Golgi structures that contain both early and late Golgi proteins, explaining how secretion can persist when COPI has been inactivated. Our findings suggest that cisternal maturation involves a COPI-dependent pathway that recycles early Golgi proteins, followed by multiple COPI-independent pathways that recycle late Golgi proteins.
Understanding Government Survival: Empirical Exploration or Analytical Models?
Authors: LAVER MICHAEL , SHEPSLE KENNETH A.
Published: July 2002

We should begin our reply to Paul Warwick by stating how very flattered we are by the diligent attention that he has given to our work on government formation. In particular, we are delighted that he has taken up and applied the simulation technology that we suggested as a way to explore cabinet stability, a matter on which we were beginning to feel like voices wailing in the wilderness.

This is not the place to bore readers of the Journal with detailed points of issue between us, of which there are obviously many. We want here to concentrate upon some larger issues provoked by Warwick's critique. These involve a debate on cabinet stability and duration between a school of thought, in Warwick's corner, that is essentially empiricist in its outlook and a school of thought, in ours, that takes analytical modelling as being more fundamental. This is a theme touched upon by Kaare Strom in his recent review essay on parliamentary democracy.
DUTY OF CARE—INSURANCE BROKERS—ADVISE OR CONSENT?
Authors: Clarke Malcolm
Published: July 2002

INSURANCE brokers are liable to their clients in both contract and tort for any failure to carry out their mandate with reasonable care and skill. In most cases it makes no difference to the outcome whether a claim against a broker is based in contract or in tort. In the event of a dispute between broker and client on whether the broker has fulfilled his mandate, in the past the first question was to establish what the broker had agreed to do and then whether the broker had breached that duty. Until recently, it could be assumed that, if breach of duty by the agent was established, the kinds of loss recoverable by the client against the agent were those which were not too remote, i.e., those which were not only caused in fact (according to the “but for” test) but also caused “in law”: loss would be too remote unless it was of a kind reasonably foreseeable (tort) or reasonably contemplated (contract) by the agent, as a consequence of breach of duty.
SLIPPING INTO UNCERTAINTY
Authors: Hopkins C.A.
Published: July 2002

HOLBECK Hall Hotel stood on the cliffs at Scarborough with views over a lawn and rose garden to the North Sea. The undercliff below the hotel was owned by Scarborough Borough Council. Over the years, natural erosion of the coastline led to relatively minor landslips in the area. The Council engaged engineers to investigate them and remedial works were carried out in 1989, but in 1993 there was a massive landslip. The lawn and rose garden fell into the sea, and the ground under the seaward wing of the hotel collapsed so badly that the whole building had to be demolished. Its owner claimed damages from the Council, and Judge John Hicks Q.C., applying Leakey v. National Trust [1980] Q.B. 485, held the Council liable for breach of a “measured duty of care”. The Court of Appeal agreed that an occupier could be under such a duty to prevent danger to a neighbour’s land from lack of support due to natural causes, but held the Council not liable because it owed no duty in relation to latent defects which could only have been discovered by extensive geological investigation: Holbeck Hall Hotel Ltd. v. Scarborough Borough Council [2000] 2 W.L.R. 1396.
ATTRIBUTING HARM: CHILD ABUSE AND THE UNKNOWN PERPETRATOR
Authors: Bainham Andrew
Published: July 2002

HOW far should we as a society concerned to protect children be prepared to run the risk of trampling on the rights of potentially innocent parents? Once the technicality is stripped away, this was essentially the issue which the House of Lords confronted in Lancashire County Council v. B [2000] 2 W.L.R. 590. The courts may only make a care or supervision order where the local authority can satisfy the “threshold conditions” in the Children Act 1989, s.31(2).
Multipoint genetic mapping of quantitative trait loci using a
variable number of sibs per family
Authors: XU SHIZHONG , GESSLER DAMIAN D. G.
Published: July 2002

We present a multipoint algorithm to map quantitative trait loci
(QTLs)
using families from
outbred populations with a variable number of sibs. The algorithm uses
information from all
markers on a chromosome simultaneously to extract information of QTL segregation.
A previous
multipoint method (Kruglyak & Lander (1995) American Journal of Human Genetics57, 439–454)
extracts information using a hidden Markov model. However, this method
is restricted to small
families (<10 sibs). We present an approximate hidden Markov model approach
that can handle
large sibships while retaining similar efficiency to the previous method.
Computer simulations
support the notion that data sampled from a small number of large families
provide more power
than data obtained from a large number of small families, under the constraint
that the total
number of individuals for the two schemes is the same. This is further

reflected in simulations with
variable family sizes, where variance in family size improves the statistical

power of QTL detection relative to a constant size control.
‘LIGHTER THAN YELLOW, BUT NOT ENOUGH’: WESTERN DISCOURSE ON
THE JAPANESE ‘RACE’, 1854–1904
Authors: KOWNER ROTEM
Published: July 2002

During the half century (1854–1904) which followed the opening of Japan's ports,
Westerners scrutinized the rediscovered archipelago and attempted to classify its inhabitants within
their racial system. Despite the claim for ‘scientific’ objectivism, Western racial views of the Japanese
were largely dictated by contemporary political and moral attitudes toward Japan. Hence, writings
on the Japanese ‘race’ reflected not only the racial knowledge of the period but also the asymmetry
between the West and Japan. These writings embodied a genuine discourse: they were propounded in
texts, historically located, and displayed a coherent system of meaning. Critically, the Western
discourse regarding the identity of the Japanese people aimed to maintain, and even produce, power
relations between the colonial powers and the local population, and as such it exerted ideological
influence on both Western readers and the Japanese. The present article traces this racial discourse,
and attempts to explain the rapid transformation of the image of the Japanese people from an almost
unknown racial entity to a national group Westerners perceived as a major racial threat.
AHMED GALAL AND ROBERT Z. LAWRENCE, ED., Building Bridges: An Egypt–US Free Trade Agreement (Washington, D.C.: Brookings Institution Press, 1998). Pp. 121. $29.95 cloth.
Authors: Salem Samira
Published: July 2002

Has the time come for a free-trade agreement (FTA) between Egypt and the United States? According to the contributors to Building Bridges, an FTA is the logical next step in the Egypt–U.S. relationship. This policy-oriented volume explores the conditions under which the benefits of an FTA between the parties would be maximized. Although the contributors reach different conclusions regarding the optimal form of the Egypt–U.S. FTA, consensus is reached on one point: an FTA between Egypt and the United States will produce economic benefits for both nations.
Conscription and Popular Resistance in Iran, 1925-1941
Authors: Cronin Stephanie
Published: July 2002

For the nationalist regimes of the inter-war Middle East, Riza Shah's Iran, Mustafa Kemal's Turkey and Hashemite Iraq, the construction of a strong national army based on universal military service was an essential element of state-building and nation-formation. Yet although conscription was ardently advocated by the nationalist intelligentsia, wherever it was actually imposed it aroused intense resentment. Nonetheless, although enforced conscription was almost universally unpopular, mass, collective and organized resistance was comparatively rare. In Iran such resistance occurred in three waves in the late 1920s. Uniquely in the Middle East, opposition in Iran was most sustained not in the rural areas but in the towns, in Isfahan and Shiraz in 1927 and in Tabriz in 1928, where it was led by the guilds and the ulama, although violent opposition was also manifested by the tribes in 1929. Riza Shah was irrevocably committed to conscription, which was a central pillar of his programme of modernization and secularization, and although prepared to temporize, was ultimately determined to crush collective resistance. By 1930 he had largely succeeded in so doing. The subsequent implementation of the policy was aided by a deliberate decision to defuse popular anger by tolerating, even encouraging, individual strategies of avoidance, in particular by allowing the manipulation of the exemptions system through bribery. As the 1930s progressed, conscription became established as an indelible feature of the new Iran.
Uganda: A Century of Existence. By P. G. OKOTH.

Kampala: Fountain Publishers, 1995. Pp. 278. £14.95, paperback

(ISBN 9970-02-0226).
Authors: GODFREY ASIIMWE B.
Published: July 2002

This book is a collection of essays presented by Makerere

University academicians at a Faculty of Arts conference held in April

1994 to commemorate the centenary of Uganda's foundation as a

state. The papers are grouped broadly by discipline, separate sections

covering history, philosophy, linguistics, literature and social and

cultural studies.
THE MURIDS: SURVEILLANCE AND COLLABORATION
Authors: ROBINSON DAVID
Published: July 2002

At the beginning of the twentieth century Muslim societies of northern
Senegal and southern Mauritania moved slowly but surely into relations of
accommodation with the French colonial regime. The process was led by
marabouts, persons who combined various forms of Islamic learning and
saintliness. It took the form of Sufi orders, often called ‘brotherhoods’, that
became anchored in the emerging economy of the peanut basin in central
Senegal. The accommodation permitted the marabouts and brotherhoods to
develop considerable autonomy in the religious, economic and social spheres
while surrendering the political and administrative domain to the French.

Of all these ‘paths to accommodation’ between Muslim societies and
French colonial authorities, the one followed by Amadu Bamba Mbacke and
the Murid movement is ostensibly the longest, the hardest, the most
complete, and the most enduring. For these reasons the Murid movement has
been much more fully studied – by Paul Marty of the colonial Muslim
Affairs Bureau in the early twentieth century and by social scientists in recent
decades.
Physiological reactions to imposed water deficit by
Andropogon gayanus cv. Bisquamulatus and Cenchrus
ciliaris cv. Biloela in a mixed fodder crop
Authors: BULDGEN A. , FRANÇOIS J.
Published: July 2002

Guinea grass (Andropogon gayanus Kunth cv. Bisquamulatus)

and Buffel grass (Cenchrus ciliaris L.
cv. Biloela) are grown as temporary fodder crops in the Sahelo-Sudanese
region of Africa.
Differences in their responses to drought conditions may be important
in optimizing cattle feeding
programmes in integrated farming systems. An experiment conducted in
a wind tunnel equipped with
a tank forming a weighable lysimeter compared net photosynthesis (A),

stomatal conductance (gs)
and leaf water potential (Ψ leaf) of both species in a mixed sward
during three simulated
environmental conditions: (1) rainy season, (2) drought period within the

rainy season and (3) dry season.

With a soil water reserve (SWR in % volume) of 8% during the drought

period and the dry season,
the Ψ leaf and A parameters were significantly lower
(P<0·001) when compared to those recorded
with a SWR of 32% in the rainy season. Mean gs values were
significantly different during each
environmental condition (P<0·001). No significant difference

(P>0·05) was found in gs and A
between the two species during the rainy and the dry season or
during a diurnal cycle, although a
significant difference (P<0·05) in Ψ leaf
existed between the species during the dry season. During
this season, Guinea grass was dormant while Buffel grass was growing slowly.

When the drought period was imposed during the rainy season (SWR declined
from 25 to 5%),
A was reduced from 19·8 to 7·7 μmol
m−2 s−1 for Guinea grass and from
16·8 to 3·7 for Buffel grass.
Ψ leaf in both species dropped below −2 MPa while gs

declined slowly from 0·70–0·80
to 0·55–0·60 cm s−1. A
was significantly higher (P<0·05) in Guinea grass during
the last days of
the drying cycle, but declined rapidly when drought was extended
up to the wilting point. Two days
after rewatering, all the parameters of both plants were restored to previous
levels.

It is concluded that Guinea grass was as drought-resistant as Buffel

grass and that no competition
for water existed between the species in the mixed sward.
The study also gives relationships between
the physiological parameters of both species and the soil water content
during a drying cycle.
Maximizing the Noodles: Class, Memory, and Capital in

Sergio Leone's Once Upon A Time In America
Authors: GODDEN RICHARD
Published: July 2002

At the end of Sergio Leone's Once Upon A Time In

America (1984), Max

(James Woods) appears finally to be dead. Max, alias Secretary Bailey,

Secretary of Commerce, has been killed on the eve of testifying before
a

Congressional Investigating Committee, late in 1968. Others due to testify

have died in suspicious circumstances. Max has told Noodles (Robert de

Niro), minutes before his disappearance, that he (Max) is

“a dead man.”

There is little doubt, it would seem, that he is dead, ingested by a refuse

wagon. But he appeared to die once before in the spring of 1933, when

Max, the bootlegger and labour fixer, was shot down and burned on his

last liquor run before the end of Prohibition. Indeed, a full sized

confectionary coffin to Prohibition is seen in the sequence, set in

Moe's bar, just prior to his death – one coffin

going, apparently, before another.

If Max has died once, and lived … perhaps he can do it twice.
CHILD UNDERNUTRITION IN WAR-TORN SOCIETY: THE ETHIOPIAN EXPERIENCE
Authors: KINFU A. YOHANNES
Published: July 2002

Using data from a cross-sectional nutrition survey conducted in rural Ethiopia between March and April 1992, roughly a year after the end of one of the longest civil wars in modern human history, this study attempts to document the magnitude and correlates of childhood undernutrition in Ethiopia. Findings from the study reveal that, at the time of the survey, 59% of children in the country were exposed to long-term or chronic undernutrition (stunted); about 4% were suffering from acute problems (wasted); and about the same proportion were both stunted and wasted. Less than a third of the country's children had normal growth. The logistic–binomial regression results demonstrated the existence of significant clustering of risks of undernutrition within areas of residence and notable differentials by age of child, duration of breast-feeding, age at introduction of supplementary foods and number of under-five siblings. Significant variations were also noted by age of household head, per capita land holding, religious affiliation and prevalence of endemic diseases in an area.
The Church Missionary Society and the Governors of Lagos, 1862–72
Authors: DARCH JOHN H.
Published: July 2002

This article examines conflict between spiritual and temporal power in nineteenth-century West
Africa – the uneasy relationship between the Church Missionary Society in Yorubaland and the
official British presence in the nearby port of Lagos. Having encouraged Britain to intervene in
Lagos in order to extirpate the slave trade, the mission soon found itself disagreeing with the policies
of the colonial government concerning both the expansion of the Lagos colony and relations with the
largely Christian Egba tribe. The dispute developed into a concerted attack on the colonial governors
both from missionaries in the field and from the CMS headquarters in London.
The Defence of an Alien Priory:
Modbury (Devon) in the 1450s
Authors: McHARDY ALISON , ORME NICHOLAS
Published: July 2002

Alien priories, the small dependencies of foreign religious houses
established in the years following the Norman Conquest, were
partly thank-offerings for military success and partly civilising
centres and reminders of home for England's new rulers. Their
foundation in the newly-conquered lands mirrored the success of the
Anglo-Normans in colonising the British Isles, since later examples were
planted in southern Scotland and in Ireland too. In England their
establishment dated from the late eleventh to the early thirteenth
centuries. They passed out of existence over a time-scale which was almost
as long, for from the late thirteenth century, during periods of Anglo-French war, they were under attack from the crown as alleged nests of
spies and as exporters of wealth to the enemy. The consequent seizure of
these small houses by the crown and their vigorous exploitation by the
exchequer reduced monastic life in all these houses and extinguished it in
many, so that the mother houses found it advantageous to sell smaller
properties while some of the larger priories were prompted to seek
denization. Such solutions are evident from the last two decades of the
fourteenth century. Apparent landmarks in this process of disintegration
and change prove, upon close inspection, to be illusory; neither the
‘expulsion’ of 1378 nor the Act of Dissolution of 1414 were such decisive
moments in the history of these houses as was once thought. Instead, we
may suggest, each of these small houses must be examined separately, for
the later history of each was distinctive. The religious life was entirely
extinguished in some, which had become merely manors, by the later
fourteenth century. Courtiers under Edward III and Richard II acquired a number which they used for the endowment of new religious houses; the
Carthusian order was an especial beneficiary. Henry V endowed his new
foundation of Sheen with alien priories, while some others were used to
augment the endowments of existing monasteries and even hospitals.
Pontefract (Yorkshire), thanks to the good offices of John of Gaunt,
became denizen in 1393.
Flow-induced patterns in directional solidification: localized morphologies in three-dimensional flows
Authors: CHEN Y.-J. , DAVIS S. H.
Published: July 2002

We consider the effect of steady, three-dimensional cellular convective fields impressed
upon the moving front of a dilute binary alloy in directional solidification. The flows
have length scales longer than the characteristic lengths of the morphological instability.
A Floquet problem with multiple degrees of freedom in space governs the
interfacial dynamics and determines the morphological patterns and marginal stability
boundaries. In the cases of weak flows the induced patterns are superpositions of rolls
modulated by the forced flows. When the flows are strong, the instability becomes
spatially localized and confined at inward flow-stagnation regions on the front. Numerical
computations and the WKB method are used to solve the eigenvalue problems,
showing various localized states depending on the structures of the imposed flows.
Transient anomalous diffusion in Poiseuille flow
Authors: LATINI MARCO , BERNOFF ANDREW J.
Published: July 2002

We revisit the classical problem of dispersion of a point discharge of tracer in laminar
pipe Poiseuille flow. For a discharge at the centre of the pipe we show that in the
limit of small non-dimensional diffusion, D, tracer dispersion can be divided into
three regimes. For small times (t [Lt ] D−1/3),
diffusion dominates advection yielding a spherically symmetric Gaussian dispersion cloud. At large times (t [Gt ] D−1), the flow is in the classical Taylor regime, for which the tracer is homogenized transversely across the pipe and diffuses with a Gaussian distribution longitudinally. However, in an intermediate regime
(D−1/3 [Gt ] t [Gt ] D−1), the longitudinal diffusion is anomalous with
a width proportional to t [Lt ] Dt2 and a distinctly asymmetric longitudinal distribution.
We present a new solution valid in this regime and verify our results numerically.
Analogous results are presented for an off-centre release; here the distribution width scales as
D1/2t3/2 in the anomalous regime. These results suggest that anomalous
diffusion is a hallmark of the shear dispersion of point discharges at times earlier than the Taylor regime.
On the effect of a central vortex on a stretched

magnetic flux tube
Authors: BAJER KONRAD , MOFFATT H. K.
Published: July 2002

Experiments and numerical simulations of fully developed turbulence

reveal the

existence of elongated vortices whose length is of the order of the

integral scale of

turbulence while the diameter is somewhere between the Kolmogorov scale
and the

Taylor microscale. These vortices are embedded in quasi-irrotational background
flow

whose straining action counteracts viscous decay and determines their cross-sectional

shape. In the present paper we analyse the effect of a stretched vortex
of this

kind on a uni-directional magnetic flux tube aligned with vorticity in
an

electrically conducting fluid. When the magnetic Prandtl number is large,

Pm[gsim ]1, the field is

concentrated in a flux tube which, like the vortex itself, has elliptical

cross-section

inclined at 45° to the principal axes of strain. We focus on the limit

Pm[Lt ]1 when

the magnetic flux tube has radial extent much larger than that of the vortex,
which

appears like a point vortex as regards its action on the flux tube. We
find the

steady-state solution valid in the entire plane outside the vortex core.
The solution

shows that the magnetic field has a logarithmic spiral component and no
definite

orientation of the inner contours. Such magnetized vortices may be expected
to exist

in MHD turbulence with weak magnetic field where the field shows a tendency
to

align itself with vorticity. Magnetized vortices may also be expected to
exist on the

solar surface near the corners of convection cells where downwelling swirling
flow

tends to concentrate the magnetic field.
Instability of two annular layers or a liquid
thread bounded by an elastic membrane
Authors: POZRIKIDIS C.
Published: July 2002

The instability of an annular layer coated on the interior side of an outer circular
tube and surrounding another annular layer coated on the exterior side of an inner
circular tube, is studied in the absence of an imposed flow due to a pressure gradient
or boundary motion. As the radius of the inner cylinder tends to vanish and the
radius of the outer cylinder tends to infinity, the inner layer reduces to a liquid
thread suspended in a quiescent infinite ambient fluid. The fluids are separated by a
membrane that exhibits constant surface tension and develops elastic tensions due to
deformation from the unstressed cylindrical shape. The surface tension is responsible
for the Rayleigh capillary instability, but the elastic tensions resist the deformation
and slow down or even prevent the growth of small perturbations. In the first part of
this paper, we formulate the linear stability problem for axisymmetric perturbations,
and derive a nonlinear eigenvalue system whose solution produces the complex phase
velocity of the normal modes. When inertial effects are negligible, there are two
normal modes; one is stable under any conditions, and the second may be unstable
when the interfacial elasticity is sufficiently small compared to surface tension, and
the wavelength of the perturbation is sufficiently long. Stability graphs are presented
to illustrate the properties of the normal modes and their dependence on the ratio of
the viscosity of the outer to inner fluid, the interfacial elasticity, and the ratios of the
cylinders' radii to the interface radius. The results show that as the interfacial elasticity
tends to vanish, the unconditionally stable mode becomes physically irrelevant by
requiring extremely large ratios of axial to lateral displacement of material points
along the trace of the membrane in an azimuthal plane. In the second part of this
paper, we investigate the nonlinear instability of an infinite thread in the limit of
vanishing Reynolds numbers by dynamical simulation based on a boundary-integral
method. In the problem formulation, the elastic tensions derive from a constitutive
equation for a thin sheet of an incompressible isotropic elastic solid described by
Mooney's constitutive law. The numerical results suggest that the interfacial elasticity
ultimately restrains the growth of disturbances and leads to slowly evolving periodic
shapes, in agreement with laboratory observations.
Call for Nominations – The Nusselt–Reynolds Prize Sponsored by Assembly of World Conferences on Experimental Heat Transfer,
Fluid Mechanics, and Thermodynamics
Authors: Kasagi Nobuhide
Published: July 2002

The Nusselt–Reynolds Prize has been established by the Assembly of World
Conferences to commemorate outstanding contributions by Wilhelm Nusselt and Osborne
Reynolds as experimentalists, researchers, educators, and authors. As many as three
prizes may be bestowed at every World Conference, one in each of the areas of heat
transfer, fluid mechanics, thermodynamics, or any combination of these.

The prize will be bestowed for outstanding scientific and engineering contributions
and eminent achievements in the fields of heat transfer, fluid mechanics, and thermodynamics
through (1) experimental studies and analytical/numerical extension of the
measurements, (2) development of experimental techniques, visualization techniques,
and/or instrumentation, and/or (3) development of design theory (that needs
experimental data) and theory-based experimental correlations. These contributions should
yield a deeper insight into physical phenomena involved or should yield significant
technological advances. In addition to research, the awardee(s) should have made
outstanding contributions to the field through teaching, design, or a combination of
such activities. The prize is based on achievement through publications or through
the application of the science or art. Nationality, age, sex, and society membership will
not be considered when evaluating qualifications of candidates. A candidate must be
living at the time of designation as a recipient of the prize.

The prize consists of a bronze plaque, and engrossed certificate, and an honorarium.
The prize is administered by the Prize Board. The deadline for accepting nominations
for the Prize is February 2, 2000. The prize will be awarded at the Fifth World
Conference during September 24–28, 2001 in Thessaloniki, Greece where the prize
winners will also present plenary lectures on their subjects.

Nominators can obtain further information and download the nomination form
from a webpage at http://www.thtlab.t.u-tokyo.ac.jp/N-Rprize.html/.
Wavefields forced by long obstacles on a beta-plane
Authors: PAGE M. A. , JOHNSON E. R.
Published: July 2002

This paper presents analytical and numerical solutions for steady flow past long
obstacles on a β-plane. In the oceanographically-relevant limit of small Rossby and
Ekman numbers nonlinear advection remains important but viscosity appears only
through the influence of Ekman pumping. A reduced boundary-layer-type equation
is derived giving the long-obstacle limit of an equation described in Page & Johnson
(1990). Analytical solutions are presented or described in various asymptotic limits
of this equation and compared with previous results for this or related flows. A
novel technique for the numerical solution of the boundary-layer equation, based on
a downstream–upstream iteration procedure, is described. Some modifications of the
asymptotic layer structure described in Page & Johnson (1991) and Johnson & Page
(1993) for the weakly nonlinear low-friction regime are outlined for the case of a
lenticular obstacle.
Stationary structures in multi-ion plasmas with differential streaming
Authors: McKENZIE J. F.
Published: July 2002

The nature of stationary-wave structures in multi-ion plasmas with differential
streaming between the ions is elucidated by making use of the concept
of a generalized sonic point for such plasmas and the Bernoulli equation for each
flowing ion species. It is shown that the Bohm criterion for the existence of solitons
and double layers is an expression of either the supersonic nature of the collective
ion flow or the subsonic nature of individual ion flows. From the perspective of the
dispersion equation for stationary waves, both of these requirements, and hence the
Bohm criterion, merely ensure that the wave is evanescent, rather than sinusoidal,
which, in turn, ensures that the system can evolve nonlinearly. The structure of
the ion flows in these transitions is determined by the Bernoulli equation, a fundamental
property of which is that the ion plasma energy exhibits a minimum where
the ion flow speed equals the local ion sound speed. This implies that for positive
flowing ions, a positive change in electric potential induces a deceleration (pile-up)
if the flow is supersonic or an acceleration (spread-out) if the flow is subsonic.
This feature limits the maximum strength of the potential in a soliton, and sheds
light on the underlying reason why double layers can only exist in very special
circumstances without the introduction of additional trapped or reflected particle
populations.
Propagation of surface waves in two-plasma
systems bounded by a metallic enclosure
Authors: STAFFORD LUC , MARGOT JOËLLE , JOHNSTON TUDOR W.
Published: July 2002

This paper examines the possibility of propagating surface waves in cylindrical
plasma–plasma structures enclosed by metal walls and submitted or not to
a static magnetic field. We consider the situation in which the inner plasma layer is
overdense while the other is underdense. It is shown that outside the electron
cyclotron resonance (ECR) conditions, the outer plasma layer plays a role similar to
that of an ordinary dielectric layer, just modifying the wavenumber without
drastically changing the general characteristics of the wave. At ECR, a major change in
the wavenumber and attenuation coefficient is observed, a cutoff occurring on the
left side of ECR and a resonance on the right side, provided the outer plasma density
is large enough. It is further found that in conditions where the outer plasma
layer thickness is very small, wave propagation still occurs, whatever the density
value in this region. This suggests that surface wave propagation is possible in
plasma–sheath–metal structures.
Electromagnetic-wave-pumped free-electron laser in a plasma channel
Authors: PARASHAR JETENDRA , PANDEY H. D. , SHARMA A. K. , TRIPATHI V. K.
Published: July 2002

An intense short laser pulse or a millimetre wave propagating through
a

plasma channel may act as a wiggler for the generation of shorter wavelengths.
When

a relativistic electron beam is launched into the channel from the opposite

direction, the laser radiation is Compton/Raman backscattered to produce

coherent radiation at shorter wavelengths. The scheme, however, requires
a

superior beam quality with energy spread less than 1% in the Raman regime.
Mode limitation and mode completion in collisionless plasmas
Authors: KNELLER M. , SCHLICKEISER R.
Published: July 2002

The relativistically correct solution of the dispersion relation
of linear plasma waves
in an isotropic unmagnetized equilibrium electron plasma leads to two new
effects
unknown from the nonrelativistic dispersion theory. First, the number of
damped
subluminal modes is limited to a few (mode-limitation effect); secondly,
for
relativistic plasma temperatures the few individual modes complement each
other in
the sense that the dispersion relations
ωR=ωR(k)
continuously match each other
(mode-completion effect). The second effect does not occur at nonrelativistic

temperatures.
Two new species of Dorymenia (Mollusca: Solenogastres: Proneomeniidae) from the South Shetland Islands (Antarctica)
Authors: García-Alvarez O. , Urgorri V. , von Salvini-Plawen L.
Published: July 2002

This paper describes two new species from the genus Dorymenia (Mollusca: Solenogastres: Proneomeniidae): D. hesperidesi sp. nov. and D. menchuescribanae sp. nov., collected during the Spanish oceanographic expeditions for the study of Antarctic benthos, BENTART'94 and BENTART'95, carried out in the area of the Livingston Island (South Shetland Islands, Antarctica). A comparative study of main specific characteristics of species belonging to the genus Dorymenia found off the South Shetland Islands and in the Bransfield Strait (Antarctica), is also included.
Jésus, le mamzer (Mt 1.18)
Authors: CHILTON BRUCE
Published: July 2002

La controverse sur la virginité de Marie a dominé l’exégèse de Mt 1.18 dans des débats récents. Les références critiques de la littérature rabbinique n’ont fait que confirmer cette tendance – à tort, comme nous le verrons. Notre tâche ici est premièrement, d’expliquer comment une forte tradition académique – poussée par son intérêt sur la virginité de Marie – s’est appropriée certaines références rabbiniques, et deuxièmement, de nous concentrer sur la question de la culture contextuelle de Mt 1.18 que la littérature rabbinique peut nous aider à comprendre et cela dans une nouvelle perspective.
Salt fortified with diethylcarbamazine (DEC) as an effective intervention for lymphatic filariasis, with lessons learned from salt iodization programmes
Authors: HOUSTON R.
Published: July 2002

DEC-fortified salt has been used successfully as a principal public health tool to eliminate lymphatic filariasis (LF) in China and, less extensively, in several other countries. Studies from 1967 to the present conducted in Brazil, Japan, Tanzania, India, China, and Taiwan involving administration of DEC salt for 18 days to 1 year, have shown this intervention to be effective for both bancroftian and brugian filariasis, as measured by reductions in both microfilarial density and positivity, and in some studies through reduction in mosquito positivity rates as well. Furthermore, studies suggest specific advantages from using DEC salt, including lack of side effects, particularly for bancroftian filariasis, and ability to reduce prevalence below 1% when used in conjunction with standard regimens of DEC tablets. However, use of DEC salt as a control tool suffers from a concern that health authorities might find it difficult to manage a programme involving a commodity such as salt. In the past decade, the very successful global efforts to eliminate iodine deficiency through universal salt iodization have demonstrated that partnership with the salt industry can be both successful and effective as a public health tool. Use of DEC salt can be most successfully implemented in areas in which (a) there is adequate governmental support for its use and for elimination of filariasis, (b) filariasis-endemic areas are clearly defined, (c) political leaders, health officials and the salt industry agree that DEC salt is an appropriate intervention, (d) the salt industry is well-organized and has known distribution patterns, (e) a successful national salt iodization effort exists, (f) a monitoring system exists that ensures adequacy of salt iodine content during production and that can also measure household coverage, and (g) measurement of impact on transmission of LF with the new antigen or filarial DNA detection methods can be established. There are advantages and disadvantages of using DEC-fortified salt compared with other interventions for LF elimination programmes, but rather than being considered as a ‘competing’ intervention, DEC salt should be seen as an additional option. Indeed, it is likely that many countries will derive maximal benefit from the synergistic effects of combining different intervention strategies in their national programmes to eliminate lymphatic filariasis.
Changes in the zymogenic cell populations of the abomasa
of sheep infected with Haemonchus contortus
Authors: SCOTT I. , STEAR M. J. , IRVINE J. , DICK A. , WALLACE D. S. , MCKELLAR Q. A.
Published: July 2002

The effects of dietary urea supplementation and of a 10-week trickle

infection regime, simulating chronic exposure to
Haemonchus contortus, on the zymogenic population of the abomasa

of Hampshire Down lambs was examined. At necropsy
a variety of parameters including plasma pepsinogen concentrations, the

wet weights of abomasal fundic mucosal pieces
and the amounts of pepsinogen contained in them, were assessed. Tissue

pepsinogen concentration was measured as the
total, acid-stable proteolytic activity present in mucosal homogenates,

as well as immunohistochemically. The immunohistochemical findings
were quantified using computer-aided image analysis. Elevation of plasma
pepsinogen
concentrations in infected animals was of borderline significance
(P=0·06). The fundic mucosae of infected animals were
heavier (P<0·02) than those of control animals, but

there was no overall change in the pepsinogen content of tissues.
Immunohistochemistry revealed that infected animals had increased numbers

of zymogenic cells, due to mucous cell
hyperplasia and the adaptation of cells to produce both mucins and
pepsinogen. The pepsinogen content of chief cells,
the major source of pepsinogen in uninfected animals, was reduced in
infected lambs. Image analysis confirmed that at
a mid-point of the mucosa of infected animals there was increased
pepsinogen-specific immunoreactivity that corresponded
with areas of mucosal hyperplasia. Mucous cell hyperplasia might therefore

allow the maintenance of pepsinogen secretion
in infected animals even if chief cell output is reduced.
Parasitic helminth genomics
Authors: BLAXTER M. , ASLETT M. , GUILIANO D. , DAUB J. , THE FILARIAL GENOME PROJECT
Published: July 2002

The initiation of genome projects on helminths of medical importance promises to yield new drug targets and vaccine
candidates in unprecedented numbers. In order to exploit this emerging data it is essential that the user community is
aware of the scope and quality of data available, and that the genome projects provide analyses of the raw data to highlight
potential genes of interest. Core bioinformatics support for the parasite genome projects has promoted these approaches.
In the Brugia genome project, a combination of expressed sequence tag sequencing from multiple cDNA libraries
representing the complete filarial nematode lifecycle, and comparative analysis of the sequence dataset, particularly using
the complete genome sequence of the model nematode C. elegans, has proved very effective in gene discovery.
Detection of viruses in livestock
Authors: CROWTHER J. R.
Published: July 2002

Diseases caused by viruses are a constant and major problem for livestock production world wide. The diseases range from
highly contagious acute forms with high mortality, to chronic disabling diseases with an insidious effect on production.
Such diseases cannot be regarded as static in nature due to the highly mutable nature of viruses and their direct selection
at the host level and indirect selection in vectors, inducing changes in pathogenicity. Considerable efforts are needed to
control these diseases including accurate and rapid diagnosis using both classical and emerging technologies. The methods
used are based on both serological and molecular biological based methods. The ELISA and use of monoclonal antibodies
are significant in the serological field whereas the Polymerase Chain reaction (PCR) and its direct and indirect uses for
identifying (sequencing) and amplification of gene products, is vital to both research and applied fields. Both areas have
to be used in a complementary way in the diagnosis of virus diseases.