bluuebunny/crossref_metadata_2025_split huggingface dataset:
Effects of nitrogen doping on the electrical conductivity and optical absorption of ultrananocrystalline diamond/hydrogenated amorphous carbon films prepared by coaxial arc plasma deposition
Authors: Zkria Abdelrahman , Katamune Yūki , Yoshitake Tsuyoshi 
Published: June 2016

Abstract
3 at. % nitrogen-doped ultrananocrystalline diamond/hydrogenated amorphous carbon composite (UNCD/a-C:H) films were synthesized by coaxial arc plasma deposition. Optically, the films possess large absorption coefficients of more than 105 cm−1 at photon energies from 3 to 5 eV. The optical band gap was estimated to be 1.28 eV. This value is smaller than that of undoped films, which might be attributable to increased sp2 fractions. The temperature dependence of the electrical conductivity implies that carrier transport follows a hopping conduction model. Heterojunctions with p-type Si substrates exhibited a typical rectifying action. From the capacitance–voltage characteristics that evidently indicated the expansion of a depletion region into the film side, the built-in potential and carrier concentration were estimated to be 0.51 eV and 7.5 × 1016 cm−3, respectively. It was experimentally demonstrated that nitrogen-doped UNCD/a-C:H films are applicable as an n-type semiconductor.
Linkage and the maintenance of variation for quantitative
traits by mutation–selection balance: an infinitesimal model
Authors: SANTIAGO ENRIQUE 
Published: July 2002

The infinitesimal model is extended to cover linkage in finite

populations. General equations to
predict the dynamics of the genetic variation under the joint effects
of mutation, selection and drift
are derived. Under truncation and stabilizing selection, the quadratic

equations for the asymptotic genetic variance (VG)
are respectivelyV2G(1+kS)+VG
(Ve−2NeVm)
−2NeVmVe=0andV2G(1+S)+VG
(Ve+γ−2NeVm)
−2NeVm(Ve+γ)=0,where Ne is the effective population size,
Vm is the mutational variance, Ve
is the environmental
variance, γ is the parameter that measures the spread of fitness
around the optimum under
stabilizing selection, k is equal to i(i−x)

where i is the selection intensity and x is the cut-off
point
under truncation selection. The term S is a function of the
number of chromosomes (v) and the average chromosome length (l):formula hereThese predictions are accurate when compared with results of
simulations of small populations
unless the number of genes is small. The infinitesimal model reduces
to the continuum of alleles
model if there is no recombination between homologous chromosomes.
Very densely welded, rheomorphic ignimbrites of
homogeneous intermediate calc-alkaline composition from the
English Lake District
Authors: BEDDOE-STEPHENS BRETT , MILLWARD DAVID 
Published: July 2002

Within a largely concealed, caldera-related volcaniclastic succession of the Ordovician
Borrowdale Volcanic Group in the western Lake District, two thick (100–350 m) ignimbrites within
the Fleming Hall Formation exhibit a number of features that in combination make them unusual
deposits. They are both homogeneous with comparatively low-SiO2 (63%) bulk composition, contain
only a moderate crystal content, are generally poor in lithic clasts, show uniformly very dense welding
(yielding parataxitic to massive vitrophyric texture) throughout and lack associated fall-out or surge
deposits. Ignimbrites of comparable bulk composition in this geological setting are usually part of
zoned sheets and/or frequently very crystal-rich. Large-scale, unzoned densely welded ignimbrites are
usually rhyodacitic to rhyolitic. By contrast, ignimbrites of intermediate composition that display
dense welding are relatively small deposits that form by agglutination of hot, plastic spatter.It is postulated that the Fleming Hall ignimbrites were derived from low column height, low explosivity
eruptions that conserved heat and minimized entrainment of accidental lithic clasts and the formation
of fine ash. The very dense welding and lack of bubble-wall shard vitroclastic textures indicate that
pyroclasts were hot and relatively dry, probably occurring as mildly vesicular (scoriaceous) fragments
which welded or fused together during aggradational deposition rather than by post-depositional compactional
loading. There is little variation in the degree of matrix or melt crystallization throughout the
two ignimbrites, despite the fact that high temperatures must have been maintained for many years following
deposition. Both display virtually ubiquitous development of micropoikilitic glass devitrification
texture, which suggests that the viscosity of the supercooled dacitic melt was sufficiently high,
probably due to initial degassing, to inhibit significant melt crystallization after deposition.The eruption of the Fleming Hall magmas was probably initiated by the rise or injection of hotter,
more basic, magma, and not by overpressurization due to volatile exsolution resulting from cooling
and crystallization. Foundering of the chamber roof caused forcible and rapid eruption of the magma,
probably along a series of volcanotectonic faults rather than a central vent, and probably flooded the
resultant caldera depression. It is predicted that this type of eruption will not have produced a widely
dispersed deposit, the bulk of which may have been largely contained within its own caldera.
Post-entrainment mineral–melt reactions in spinel peridotite

xenoliths from Inver, Donegal, Ireland
Authors: SHAW CLIFF S. J. , EDGAR ALAN D. 
Published: July 2002

Spinel lherzolite and harzburgite xenoliths hosted in an alkali

basalt dyke near Inver, Donegal,

Ireland show abundant evidence of interaction between xenolith minerals
and

the host melt. Of particular

interest are primary Cr-diopside and spinel with sieve-textured coronas.

Coronas on primary Cr-diopside are

up to 3 mm wide and are associated with veinlets of devitrified glass.
The

coronas comprise secondary Cr-diopside

with vermicular, interstitial alkali feldspar and chlorite grains up to

100 µm in size. The inclusion-free

Cr-diopside cores are Al- and Na-rich whereas the coronas are Al- and

Na-depleted and Ti-enriched.

Sieve-textured spinels have similar texture to the clinopyroxene grains
and

are also associated with veinlets

of infiltrated glass. However, the interstitial inclusions in the

sieve-textured region are chlorite and

nepheline. Inclusion-free spinel is part of a chromite–spinel

solid solution and is Ti-poor. Spinel in the coronas

has a greater chromite and ulvospinel component and falls close

to a mixing line with spinel in the host

alkali basalt. In addition to the sieve-textured grains, primary olivine

in contact with infiltrated glass has Fe-rich

rims, and orthopyroxene has broken down to form rims of olivine,

clinopyroxene and a K-rich phase

similar in composition to alkali-feldspar. Comparison of the compositions
of

the inclusion-free cores and

sieve-textured rims shows that the rims have chemical signatures consistent

with partial melting, that is, Al

and Na depletion for clinopyroxene and Cr-enrichment for spinel. The

textures of the coronas, particularly

those around spinel and the reaction margins on orthopyroxene are identical

to those produced during dissolution experiments.We suggest that silicate liquid from the host magma infiltrated the

xenoliths during their ascent and since

it was not in equilibrium with the xenolith minerals caused reaction. The

occurrence of K-bearing interstitial

minerals in the sieve-textured grains and reacted orthopyroxenes indicate

that the coronas did not form by

simple melting since none of the minerals that underwent breakdown are

K-bearing. We suggest that the

sieve-textured grains formed initially by partial melting and reaction

associated with decompression and

infiltration of liquid from the host magma. The melts included in the

reacted phases were enriched in K by

diffusion from the Si-poor infiltrated melt into the more Si-rich melt

inclusions in the coronas.
The Lower Silurian Osmundsberg K-bentonite.

Part II: mineralogy, geochemistry, chemostratigraphy

and tectonomagmatic significance
Authors: HUFF WARREN D. , BERGSTRÖM STIG M. , KOLATA DENNIS R. , SUN HEPING 
Published: July 2002

The Lower Silurian Osmundsberg K-bentonite is a

widespread ash bed that occurs throughout

Baltoscandia and parts of northern Europe. This paper describes

its characteristics at its type locality in the

Province of Dalarna, Sweden. It contains mineralogical and

chemical characteristics that permit its regional

correlation in sections elsewhere in Sweden as well as Norway,

Estonia, Denmark and Great Britain. The

<2 μm clay fraction of the Osmundsberg bed contains

abundant kaolinite in addition to randomly ordered

(RO) illite/smectite (I/S). Modelling of the X-ray

diffraction tracings showed the I/S consists of 18% illite

and 82% smectite. The high smectite and kaolinite content is

indicative of a history with minimal burial

temperatures. Analytical data from both pristine melt inclusions

in primary quartz grains as well as whole

rock samples can be used to constrain both the parental magma

composition and the probable tectonic setting

of the source volcanoes. The parental ash was dacitic to

rhyolitic in composition and originated in a tectonically

active collision margin setting.Whole rock chemical fingerprinting of coeval beds elsewhere

in Baltoscandia produced a pronounced

clustering of these samples in the Osmundsberg field of the

discriminant analysis diagram. This, together

with well-constrained biostratigraphic and lithostratigraphic

data, provides the basis for regional correlation

and supports the conclusion that the Osmundsberg K-bentonite is

one of the most extensive fallout ash beds

in the early Phanerozoic. The source volcano probably lay to

the west of Baltica as part of the subduction

complex associated with the closure of Iapetus.
Influence of ions on growth and production of exopolysaccharides
by Lactobacillus delbrueckii subsp. bulgaricus NCFB 2772
Authors: GROBBEN GERT J. , BOELS INGEBORG C. , SIKKEMA JAN , SMITH MARK R. , DE BONT JAN A. M. 
Published: July 2002

Several lactic acid bacteria produce exopolysaccharides (EPS), either attached to
the cell wall or excreted into the environment as slime material. EPS produced by
Lactobacillus delbrueckii subsp. bulgaricus (Lb. bulgaricus)
and Streptococcus thermophilus play an important role in improving the texture and stability of yogurt
and preventing syneresis (Cerning, 1990; Nakajima et al. 1990). The amount and
composition of the EPS produced by lactic acid bacteria are dependent on a number
of factors, such as temperature, initial pH, carbon source and the availability of
minerals, vitamins and other medium components.In previous work it was shown that the production and sugar composition of the
EPS from Lb. bulgaricus NCFB2772 are affected by the carbohydrate source (Grobben
et al. 1995, 1996). In a simplified defined medium, from which several vitamins and
trace elements were omitted, EPS production by Lb. bulgaricus significantly
increased, although growth of the strain was reduced (Grobben et al. 1998).
Flow past a square-section cylinder with a wavy stagnation face
Authors: DAREKAR RUPAD M. , SHERWIN SPENCER J. 
Published: July 2002

Numerical investigations have been performed for the flow past square-section cylinders
with a spanwise geometric deformation leading to a stagnation face with a
sinusoidal waviness. The computations were performed using a spectral/hp element
solver over a range of Reynolds numbers from 10 to 150.Starting from fully developed shedding past a straight cylinder at a Reynolds
number of 100, a sufficiently high waviness is impulsively introduced resulting in
the stabilization of the near wake to a time-independent state. It is shown that
the spanwise waviness sets up a cross-flow within the growing boundary layer on
the leading-edge surface thereby generating streamwise and vertical components
of vorticity. These additional components of vorticity appear in regions close to the
inflection points of the wavy stagnation face where the spanwise vorticity is weakened.
This redistribution of vorticity leads to the breakdown of the unsteady and staggered
Kármán vortex wake into a steady and symmetric near-wake structure. The steady
nature of the near wake is associated with a reduction in total drag of about 16% at
a Reynolds number of 100 compared with the straight, non-wavy cylinder.Further increases in the amplitude of the waviness lead to the emergence of hairpin
vortices from the near-wake region. This wake topology has similarities to the wake
of a sphere at low Reynolds numbers. The physical structure of the wake due to
the variation of the amplitude of the waviness is identified with five distinct regimes.
Furthermore, the introduction of a waviness at a wavelength close to the mode A
wavelength and the primary wavelength of the straight square-section cylinder leads
to the suppression of the Kármán street at a minimal waviness amplitude.
Direct simulation of turbulent supersonic boundary layers by an extended temporal approach
Authors: MAEDER THIERRY , ADAMS NIKOLAUS A. , KLEISER LEONHARD 
Published: July 2002

The present paper addresses the direct numerical simulation of turbulent
zero-pressure-gradient boundary layers on a flat plate at Mach numbers 3, 4.5 and 6
with momentum-thickness Reynolds numbers of about 3000. Simulations are performed
with an extended temporal direct numerical simulation (ETDNS) method.
Assuming that the slow streamwise variation of the mean boundary layer is governed
by parabolized Navier–Stokes equations, the equations solved locally in time with a
temporal DNS are modified by a distributed forcing term so that the parabolized
Navier–Stokes equations are recovered for the spatial average. The correct mean flow
is obtained without a priori knowledge, the streamwise mean-flow evolution being
approximated from its upstream history. ETDNS reduces the computational effort by
up to two orders of magnitude compared to a fully spatial simulation.We present results for a constant wall temperature Tw chosen to be equal to
its laminar adiabatic value, which is about 2.5 T∞,
4.4 T∞ and 7 T∞, respectively,
where T∞ is the free-stream temperature for the three Mach numbers considered.
The simulations are initialized with transition-simulation data or with re-scaled
turbulent data at different parameters. We find that the ETDNS results closely match
experimental mean-flow data. The van Driest transformed velocity profiles follow the
incompressible law of the wall with small logarithmic regions.Of particular interest is the significance of compressibility effects in a Mach number
range around the limit of M∞ ≃ 5, up to which Morkovin's hypothesis is believed
to be valid. The results show that pressure dilatation and dilatational dissipation
correlations are small throughout the considered Mach number range. On the other
hand, correlations derived from Morkovin's hypothesis are not necessarily valid, as is
shown for the strong Reynolds analogy.
The proper orthogonal decomposition of pressure

fluctuations surrounding a turbulent jet
Authors: ARNDT R. E. A. , LONG D. F. , GLAUSER M. N. 
Published: July 2002

It is shown that the pressure signal measured at the outer edge
of a

jet mixing layer is

entirely hydrodynamic in nature and provides a good measure of the large-scale

structure of the turbulent flow. Measurement of the pressure signal provides
a unique

opportunity to utilize proper orthogonal decomposition (POD) to deduce
the

streamwise structure. Since pressure is a scalar, a significant reduction

in the numerical

and experimental complexity inherent in the analysis of velocity vector

fields results.The POD streamwise eigenfunctions show that the structure associated
with any

frequency–azimuthal mode number combination displays the

general characteristics of

amplification–saturation–decay of an instability wave,

all within about three

wavelengths. High-frequency components saturate early in x and
low-frequency

components saturate further downstream, indicative of the inhomogeneous
character

of the flow in the streamwise direction. Application of the POD technique
allows the

phase velocity to be determined taking into account the inhomogeneity of
the flow in

the streamwise direction. The phase velocity of each instability

wave (POD eigenvector)

is constant and equal to 0.58Uj, indicating

that the jet structure is non-dispersive.Using the shot-noise decomposition, a characteristic event is constructed.

This event

is found to contain evidence of both pairings and triplings of vortex

structures. The

tripling results in a rapid increase in the first asymmetric

(m=1) component. On

average, pairing occurs once every four

Uj/D while tripling occurs

once every 13Uj/D.
Nonlinear self-excited oscillations of a ducted flame
Authors: DOWLING A. P. 
Published: July 2002

Self-excited oscillations of a confined flame, burning in

the wake of a bluff-body flame-holder, are considered. These

oscillations occur due to interaction between unsteady

combustion and acoustic waves. According to linear theory, flow disturbances
grow

exponentially with time. A theory for nonlinear oscillations

is developed, exploiting the

fact that the main nonlinearity is in the heat release rate,

which essentially ‘saturates’.

The amplitudes of the pressure fluctuations are sufficiently

small that the acoustic waves remain linear. The time evolution of the
oscillations

is determined by numerical

integration and inclusion of nonlinear effects is found to lead to

limit cycles of finite

amplitude. The predicted limit cycles are compared with results from experiments

and from linear theory. The amplitudes and spectra of the limit-cycle oscillations

are in reasonable agreement with experiment. Linear theory is found to
predict the

frequency and mode shape of the nonlinear oscillations remarkably well.
Moreover,

we find that, for this type of nonlinearity, describing function

analysis enables a good

estimate of the limit-cycle amplitude to be obtained from linear theory.Active control has been successfully applied to eliminate these oscillations.
We

demonstrate the same effect by adding a feedback control system to our
nonlinear

model. This theory is used to explain why any linear controller capable

of stabilizing the linear flow disturbances is also able to stabilize

finite-amplitude oscillations in the nonlinear limit cycles.
An exploration of evolved mental mechanisms for dominant and subordinate behaviour in relation to auditory hallucinations in schizophrenia and critical thoughts in depression
Authors: GILBERT P. , BIRCHWOOD M. , GILBERT J. , TROWER P. , HAY J. , MURRAY B. , MEADEN A. , OLSEN K. , MILES J. N. V. 
Published: July 2002

Background. Mental mechanisms have evolved to enable animals (and humans) to be able to function in various social roles. It is suggested that the nature and functions of the mental mechanisms that enable animals to act as a hostile–dominant or threatened–subordinate can be distinguished. It is further suggested these can be internally activated and ‘play off’ against each other, such that a person ‘attacks’ themselves and then responds to their own internal attacks with subordinate defences. Hence, a depressed person can submit, feel defeated, belittled, beaten down, or want to run away (escape) from their own self-attacking thoughts, while psychotic voice hearers can feel similarly to their hostile voices. Such internal interactions may relate to depression in both psychotic voice hearers and depressed people.Method. A group of 66 voice hearers with a diagnosis of schizophrenia and 50 depressed patients were compared on a series of self-report questionnaires measuring the power of hostile self-directed thoughts/voices and the activation of defensive responses, especially fight/flight.Results. We present evidence that schizophrenic, malevolent voice hearers and self-critical depressed people experience their hostile, internally generated voices/thoughts as powerful, dominating and controlling (i.e. have typical characteristics of a hostile dominant). Moreover, these voices/thoughts activate evolved subordinate defences such as fight/flight and these are associated with depression in both depression and schizophrenia.Conclusion. Conceptualizing aspects of depressed and psychotic thinking as relating to evolved mental mechanisms, which are role serving, but can internally play off against each other, may open new ways of investigating certain aspects of severe pathologies.
Risk factors and life processes associated with the
onset of suicidal behaviour during adolescence and
early adulthood
Authors: FERGUSSON D. M. , WOODWARD L. J. , HORWOOD L. J. 
Published: July 2002

Background. This study examined associations between childhood circumstances, adolescent
mental health and life events, and the development of suicidal behaviour in young people aged
between 15 and 21 years.Method. Data were gathered over the course of a 21-year longitudinal study of a birth cohort of
1265 children born in New Zealand. The measures collected included: (1) patterns of suicidal
behaviour (ideation, attempt) (15–21 years); (2) social background, family functioning, parental
and individual adjustment during childhood (0–16 years); and (3) time dynamics of mental health
and stressful life events during adolescence and early adulthood (15–21 years).Results. By the age of 21 years, 28·8% of the sample reported having thought about killing
themselves and 7·5% reported having made a suicide attempt. The childhood profile of those at
greatest risk of suicidal behaviour was that of a young person reared in a family environment
characterized by socio-economic adversity, marital disruption, poor parent–child attachment and
exposure to sexual abuse, and who as a young adolescent showed high rates of neuroticism and
novelty seeking. With the exception of the socio-economic and personality measures, the effects of
childhood factors were largely mediated by mental health problems and exposure to stressful life
events during adolescence and early adulthood. Mental health problems including depression,
anxiety disorders, substance use disorder, and to some extent conduct disorder, in addition to
exposure to adverse life events, were significantly associated with the onset of suicidal behaviours.Conclusions. Findings support a life course model of the aetiology of suicidal behaviour in which
risk of developing suicidal behaviour depends on accumulative exposure to a series of social, family,
personality and mental health factors.
Unemployment and suicide: a cohort analysis of
social factors predicting suicide in the US National
Longitudinal Mortality Study
Authors: KPOSOWA AUGUSTINE J. 
Published: July 2002

Background. The purpose of the study was to examine the effect of employment status measured
at baseline on the risk of suicide by years of follow-up, using a large nationally representative
sample of the US population.Methods. Cox regression models were applied to data from the National Longitudinal Mortality
Study, based on the 1979–1989 follow-up. In estimating the effect of baseline employment status on
suicide, adjustments were made for baseline demographic and socio-economic variables.Results. After 3 years of follow-up, unemployed men were a little over twice as likely to commit
suicide as their employed counterparts. Among men, the lower the socio-economic status, the higher
the suicide risk. Among women, in each year of follow-up, the unemployed had a much higher
suicide risk than the employed. After 9 years of follow-up unemployed women were over three times
more likely to kill themselves than their employed counterparts.Conclusions. Unemployment is strongly related to suicide, but this relationship is more enduring
and stronger among women. For men, the unemployment effect is stronger at earlier years of
follow-up. In women, unemployment increases the risk of suicide regardless of the number of
follow-up years. The finding with regard to women disconfirms earlier research reports suggesting
that unemployment affects suicide only in men.