bluuebunny/crossref_metadata_2025_split huggingface dataset:
Break-up of a falling drop containing dispersed particles
Authors: NITSCHE J. M. , BATCHELOR G. K. 
Published: July 2002

The general purpose of this paper is to investigate some consequences

of the randomness of the velocities of interacting rigid particles falling
under

gravity through viscous

fluid at small Reynolds number. Random velocities often imply diffusive
transport

of the particles, but particle diffusion of the conventional kind exists
only

when the

length characteristic of the diffusion process is small compared with the
distance

over which the particle concentration is effectively uniform. When this
condition

is not satisfied, some alternative analytical description of the dispersion

process is

needed. Here we suppose that a dilute dispersion of sedimenting particles
is bounded

externally by pure fluid and enquire about the rate at which particles
make outward

random crossings of the (imaginary) boundary. If the particles are initially

distributed

with uniform concentration within a spherical boundary, we gain the convenience

of approximately steady conditions with a velocity distribution like that
in

a falling

spherical drop of pure liquid. However, randomness of the particle velocities
causes

some particles to make an outward crossing of the spherical boundary and
to be

carried round the boundary and thence downstream in a vertical ‘tail’.

This is the nature of break-up of a falling cloud of particles.A numerical simulation of the motion of a number of interacting particles

(maximum 320) assumed to act as Stokeslets confirms the validity of the
above picture

of the way in which particles leak away from a spherical cluster of particles.
A

dimensionally correct empirical relation for the rate at which particles
are

lost from

the cluster involves a constant which is indeed found to depend only weakly
on the

various parameters occurring in the numerical simulation. According to
this relation

the rate at which particles are lost from the blob is proportional to the

fall speed of

an isolated particle and to the area of the blob boundary. Some photographs
of a

leaking tail of particles in figure 5 also provide support for the

qualitative picture.
Three-dimensional eddy structure in a cylindrical container
Authors: SHANKAR P. N. 
Published: July 2002

We consider Stokes flow in a cylindrical container of circular

section induced by the

uniform translatory motion of one of the endwalls. This flow field is of

interest because

it is possible to get reliable analytical descriptions of important three-dimensional

structures such as the primary and corner eddies. It is shown, using a

result of Tran-Cong & Blake, that separable solutions exist which can

be combined to yield vector

eigenfunctions that satisfy the sidewall boundary conditions provided the
eigenvalues

satisfy the transcendental equationformula here
Turbulence-induced rectified flows in rotating fluids
Authors: ZHANG XIUZHANG , BOYER DON L. , FERNANDO HARINDRA J. S. 
Published: July 2002

Laboratory experiments dealing with Reynolds stress gradients

in shear-free turbulence

in homogeneous rotating fluids were conducted to better understand associated

physical phenomena. The study was motivated by possible applications to
the oceanic

environment where such Reynolds stress gradients are ubiquitous (e.g. in
the vicinity

of the continental shelf break, where turbulence decays away from the boundary).
The

turbulence was generated by vertical oscillations of a circular shaft with O-ring surface

roughness elements; the oscillation axis coincided with the axis of symmetry
of the

cylindrical test cell.In the absence of background rotation, the turbulence is strong in the
immediate

vicinity of the shaft surface and decays with the radial distance,

r. The turbulence in the boundary layer is such that

ur∼uθ∼w,

where ur, uθ, w

are the radial, azimuthal

and vertical r.m.s. velocity components, respectively. These velocity components
are

found to be proportional to Sω, where S and

ω are the stroke and frequency of the shaft

oscillations, respectively, i.e. much the same as for the case of oscillating-grid

turbulence, which has been studied extensively.When background rotation is present, the steady-state turbulent intensity
close to

the shaft is similar to that of the non-rotating experiments. Away from

the shaft, in the

central portion of the test cell, large-scale motions containing randomly
distributed

cyclonic and anticyclonic vortices are developed owing to small local Rossby
numbers.

In the vicinity of the shaft, a rectified anticyclonic flow Uθ is observed. The magnitude

of Uθ is found to be proportional to the

characteristic r.m.s. turbulence velocity u, but

independent of the rate of background rotation.Consideration of the equations of motion shows that mean flows should
not be

expected if background rotation is absent. With rotation, however, the
equations

indicate that the turbulent stresses can initiate, further develop and

then maintain a

mean anticyclonic (rectified) flow around the cylinder; the azimuthal momentum

equation is shown to play a critical role in the generation of the mean

anticyclonic flow.
Shear flow over a self-similar expanding
pulmonary alveolus during rhythmical breathing
Authors: HABER S. , BUTLER J. P. , BRENNER H. , EMANUEL I. , TSUDA A. 
Published: July 2002

Alternating shear flow over a self-similar, rhythmically expanding hemispherical depression
is investigated. It provides a fluid-mechanical model for an alveolated respiratory
unit, by means of which the effect of lung rhythmical expansion on gas mixing
as well as aerosol dispersion and deposition can be studied. The flow is assumed to
be very slow and governed by the quasi-steady linear Stokes equations. Consequently,
superposition of the following two cases provides an easy route toward characterizing
the aforementioned flow field. The first case treats the flow field that is generated
by a rhythmically expanding spherical cap (the alveolus). The cap is attached at its
rim to a circular opening in an expanding unbounded plane bounding a semi-infinite
fluid region. The rate of expansion of the cap and the plane are chosen such as to
maintain the system's configurational self-similarity. The second case addresses the
flow disturbance that is generated by an alternating shear flow encountering a rigid
hemispherical cavity in a plane bounding a semi-infinite fluid domain.For the first case, a stream-function representation employing toroidal coordinates
furnishes an analytical solution, whereas the second case was solved numerically by
Pozrikidis (1994). Linear superposition of the two flow cases results in particularly
rich streamline maps. In the symmetry plane (bisecting the cap and parallel to the
mean shear flow), for a certain range of shear to expansion-rate ratios, the streamline
maps are self-similar and display closed orbits and two internal stagnation points.
One of the stagnation points is a ‘centre’ surrounded by closed streamlines whereas
the other constitutes a ‘saddle point’. For other planes, no stagnation points exist in
the field, but the streamlines associated with the saddle point display complex looping
patterns. These unique flow structures, when subjected to a small perturbation (e.g. a
small asynchrony between ductal and alveolar entering flows) cause highly complex
stochastic particle trajectories even in the quasi-static Stokes alveolar flow. The
observed irreversible flow phenomena in a rhythmically expanding alveolus may be
partially responsible for the ‘stretch-and-fold’ flow mixing patterns found in our recent
flow visualization studies performed in excised animal lung acini.
Electro-convulsive therapy practices in the community
Authors: PRUDIC J. , OLFSON M. , SACKEIM H. A. 
Published: July 2002

Background. Controlled studies have demonstrated that variations in electro-convulsive therapy (ECT) technique impacts on efficacy and cognitive side effects. However, there is little information on the extent of variation in how ECT is practiced in community settings in the United States.Methods. A survey of practice patterns was conducted at ECT facilities in the greater New York City metropolitan area.Results. The 59 facilities varied considerably in many aspects of ECT practice, often clearly departing from the standards in the field. The more intensive the form of ECT used at facilities, the less likely was cognitive status assessed following the treatment course.Conclusion. There is marked variability in the nature of ECT practices in community settings. The extent to which this variability impacts on the benefits and risks of ECT needs to be examined.
Three- to 5-year prospective follow-up of outcome in major depression
Authors: VAN LONDEN L. , MOLENAAR R. P. G. , GOEKOOP J. G. , ZWINDERMAN A. H. , ROOIJMANS H. G. M. 
Published: July 2002

Background. A Dutch cohort of predominantly out-patient
DSM-III-R
major depressive patients
was followed for 3 to 5 years after start of treatment in a
psycho-neuro-endocrinological prediction
study. The study design permitted description of the course of
remissions, relapses and recurrences.Methods. Pharmacological treatment was standardized, psychotherapy

was tailored to the needs of
the patient, follow-ups were done monthly until 3 years or more after the
initial recruitment.Results. After 9 months 49% of the patients had reached full

remission and 45% were in partial
remission. During the following 3 to 5 years 82% of the patients had reached
a period of full
remission. Sixteen per cent of the patients needed 2 years or more
before full remission. A relapse
or recurrence rate of 41% within 5 years was found. Patients with residual
symptoms relapsed
particularly in the first 4 months after remission, while patients
without residual symptoms recurred
mainly after 12 months after remission. Previous depressive episodes and
psychoticism predicted
relapse. Psychomotor retardation at inception predicted a longer time to
partial remission.Conclusion. In most cases, major depression is a seriously

impairing episodic disease. This is also
true for a sample of predominantly out-patients treated at a university
clinic.
Is subcortical disease associated with a poor response
to antidepressants? Neurological, neuropsychological
and neuroradiological findings in late-life depression
Authors: SIMPSON S. , BALDWIN R. C. , JACKSON A. , BURNS A. S. 
Published: July 2002

Background. Late-life depression is associated with
increased subcortical white matter hyper-intensities. There is some evidence

that they are associated with a poorer response to acute
treatment. Neurological signs and neuropsychological dysfunction are further
evidence of
abnormalities in the brain, but they have not been studied in relation
to therapy resistance.Methods. A prospective study of 24 normal controls and
75 consecutive elderly (aged 65 to 85)
patients with DSM-III-R major depression entered a naturalistic study
of treatment. Assessment of
response to monotherapy and then lithium augmentation or ECT created three
outcome groups.
Investigations included magnetic resonance brain imaging, neuropsychological
and neurological
examination.Results. Response to monotherapy within 12 weeks was
shown by 42·7%, a further 37·3%
responded to lithium augmentation or ECT within 24 weeks and 20% had responded
poorly to all
treatments at 24 weeks. Subcortical hyperintensities were significantly
increased in the more
resistant patients. These included confluent deep white matter,
multiple (>5) basal ganglia lesions
and pontine reticular formation lesions. Most of the neuropsychological

impairment was restricted
to the resistant groups and was of a subcortico-frontal type.
Extrapyramidal, frontal and pyramidal
neurological signs characterized the resistant groups. The combination
of extrapyramidal signs,
pyramidal tract signs and impairment of motor hand sequencing
strongly predicted resistance to 12
weeks of antidepressant monotherapy with 89% sensitivity and 95% specificity.Conclusion. In late-life depression a poor response to
antidepressant monotherapy can be expected
in those patients with a frontal lobe syndrome, extrapyramidal signs or

if MRI T2-weighted lesions
are present in both the basal ganglia and the pontine reticular formation.
The North Staffordshire Suicide Study: a
case–control study of suicide in one health district
Authors: BOARDMAN A. P. , GRIMBALDESTON A. H. , HANDLEY C. , JONES P. W. , WILLMOTT S. 
Published: July 2002

Background. The aim of the study was to identify sociodemographic
and clinical risk factors for
death from suicide and undetermined injury in residents of one health district.Method. Data were collected on all cases of suicide (ICD-9
E950–959) and undetermined injury
(ICD-9 E980–989) for residents in North Staffordshire Health District
between 1991 and 1995.
Controls, identified from the Coroner's inquest register, who died
from other causes, were matched
for age and sex.Results. Two hundred and twelve pairs of cases and matched
controls were identified. Multivariate
analysis (conditional logistic regression) showed that the risk of death
due to suicide and
undetermined death was associated with: recent separation, relationship
difficulties, experience of
financial difficulties, history of past criminal charges or contact with
the police, a past history of
deliberate self-harm, being on psychotropic medication at the time of death
and a diagnosis of
bipolar affective disorder. For sociodemographic variables, a univariate
analysis found associations
between the cases and being separated, living alone, having a past history
of criminal charges and
unemployment. Cases were more likely to have a psychiatric disorder, past
history of deliberate self-harm
and a past history of psychiatric contact for themselves or a family member.
Controls were
more likely to have a current medical disorder. Cases were more likely
than controls to be on any
form of medication at the time of death and to have received a prescription
for psychotropic or non-psychotropic
medication in the week and month before death. Cases were more likely than
controls
to have had contact with medical services in the week and month before
death, with the general
practitioner in the week before death and with psychiatric services at
any time in the year before
death. Strong associations were found between suicide and undetermined
injury and life events such
as recent separation and bereavement, and financial and relationship difficulties.Conclusions. The study provides an analytical investigation
utilizing a dead control group, data
gathered from several sources and adequate numbers of cases. It confirms
many of the risk factors
identified in other studies and highlights the high proportion of suicides
who have been in recent
contact with the criminal justice system or have been prescribed medication
shortly before death.
Prevalence of suicide ideation and suicide attempts
in nine countries
Authors: WEISSMAN M. M. , BLAND R. C. , CANINO G. J. , GREENWALD S. , HWU H.-G. , JOYCE P. R. , KARAM E. G. , LEE C.-K. , LELLOUCH J. , LEPINE J.-P. , NEWMAN S. C. , RUBIO-STIPEC M. , WELLS J. E. , WICKRAMARATNE P. J. , WITTCHEN H.-U. , YEH E.-K. 
Published: July 2002

Background. There are few cross-national comparisons of
the rates of suicide ideation and attempts
across diverse countries. Nine independently conducted epidemiological
surveys using similar
diagnostic assessment and criteria provided an opportunity to obtain that
data.Methods. Suicide ideation and attempts were assessed on the
Diagnostic Interview Schedule in over
40000 subjects drawn from the United States, Canada, Puerto Rico, France,
West Germany,
Lebanon, Taiwan, Korea and New Zealand.Results. The lifetime prevalence rates/100 for suicide
ideation ranged from 2·09 (Beirut) to 18·51
(Christchurch, New Zealand). Lifetime prevalence rates/100 for suicide
attempts ranged from 0·72
(Beirut) to 5·93 (Puerto Rico). Females as compared to males had
only marginally higher rates of
suicidal ideation in most countries, reaching a two-fold increase in Taiwan.
Females as compared
to males had more consistently higher rates for suicide attempts, reaching
a two- to three-fold
increase in most countries. Suicide ideation and attempts in most countries
were associated with
being currently divorced/separated as compared to currently married.Conclusions. While the rates of suicide ideation varied widely
by country, the rates of suicide
attempts were more consistent across most countries. The variations were
only partly explained by
variation in rates of psychiatric disorders, divorce or separation among
countries and are probably
due to cultural features that we do not, as yet, understand.
Do general practitioners' attitudes towards
depression predict their clinical behaviour?
Authors: DOWRICK C. , GASK L. , PERRY R. , DIXON C. , USHERWOOD T. 
Published: July 2002

Background. GPs' attitudes towards depression vary, as do their abilities to detect and manage it
effectively. Associations between attitudes and clinical behaviour have not yet been demonstrated
directly. We tested two hypotheses: (1) that questionnaire measures of GPs' confidence in
identifying depression predict their ability to identify depression in their patients; and (2) that GPs
who prefer antidepressants prescribe more than those who prefer psychotherapy.Methods. Forty GPs in Liverpool and Manchester completed the Depression Attitude Questionnaire
(DAQ) and were asked for prescribing (PACT) information. Attender surveys using the
General Health Questionnaire (GHQ-12), in combination with GP ratings of patients' psychological
status, generated indices for GPs' case identification, bias and accuracy. We tested associations
between these indices and the four DAQ components, in particular GPs' confidence in diagnosis,
across a total of 1436 patients. We also compared the DAQ component on attitudes to treatment
with relevant PACT data.Results. The DAQ assessment of GPs' ability to identify cases of depression bore no relationship
to their observed ability, as measured by accuracy, bias, or identification indices. However, there
were significant associations between observed diagnostic ability and: preference for psychotherapy;
ease in managing depression; and, belief in successful treatment. PACT data were available for 26
(65%) GPs. There was an association between preference for antidepressants and prescription of
SSRIs (rs 0·3981, P < 0·044), but not for overall antidepressant or tricyclic prescribing, or for dose
of dothiepin.Conclusions. The DAQ measure of ease of identification is not valid when compared to actual
clinical practice. The ability of GPs to identify depression may not be an independent variable, but
may rather reflect other beliefs, attitudes and skills. This has considerable implications for
educational interventions in primary care.
Six-month and 12-month mental health outcome of
medical and surgical patients admitted to general
hospital
Authors: BALESTRIERI M. , BISOFFI G. , DE FRANCESCO M. , ERIDANI B. , MARTUCCI M. , TANSELLA M. 
Published: July 2002

Background. We have recently reported a two-phase study on psychiatric morbidity in a sample of
general hospital patients. This paper reports the results of the 6-month and 12-month follow-up of
these patients.Methods. The screening questionnaire was the GHQ-12. The main diagnostic instrument used in
the second phase was the CIDI-PHC. All patients who had been interviewed with CIDI-PHC
(N = 363) were followed-up and the baseline assessment was compared with the scoring on
questionnaires administered in the 6-month postal enquiry and with the psychopathological status
at 12-month, elicited with a telephone structured interview.Results. Sixty-two and 87% of patients completed the 6- and 12-month follow-up assessment
respectively. The first follow-up indicated no significant decrease in the level of symptoms. The 12-month follow-up interview showed that 23% of males and 40% of females had poor/mostly poor
mental health. The logistic model showed that females with a definite ICD-10 diagnosis, admitted
to a medical department, who had consumed psychotropic drugs in the previous year, had the most
unfavourable outcome. The risk of a poor/mostly poor outcome steadily increased with the severity
of the psychopathology during hospitalization.Conclusion. In medical and surgical general hospital patients the risk factors associated with a poor
mental health outcome are similar to those found in primary care patients. Greater attention should
be paid in assessing routinely mental health status of general hospital patients during hospitalization.
Information processing deficits in relatives of manic depressive patients
Authors: PIERSON A. , JOUVENT R. , QUINTIN P. , PEREZ-DIAZ F. , LEBOYER M. 
Published: July 2002

Background. The importance of genetic factors in the aetiology of manic-depressive illness (MDI)
has been repeatedly confirmed and indicators of vulnerability to the illness in families with affective
disorders are needed. Abnormal event-related potentials (ERP) may be markers of genetic
vulnerability to mental illness. Long latency and low amplitude of P300 have consistently been
reported in schizophrenic patients and their relatives. A few studies have also shown P300 deficits
in MDI patients, but no ERP study has been performed on their relatives.Methods. ERPs were recorded during an auditory oddball task in 19 relatives belonging to families
with two or more bipolar patients and in controls with no familial or personal history of affective
disorders. The relatives were selected as having no affective disorders on a lifetime basis, but eight
had an anxiety disorder.Results. In all relatives, a lower P300 amplitude and a longer P300 latency was found, with much
longer reaction time and post-N200 duration till button-press than controls. A lack of P300
amplitude dominance in the right hemisphere was also found in relatives in comparison with
controls. There also appeared to be a frontal predominance of ERP abnormalities in relatives.Conclusion. We report the first evidence of deficits in reaction time and in P300 amplitude and
latency, and a lack of P300 right-sided dominance, in relatives of manic-depressive patients. This
pattern may constitute an endophenotypic marker of manic-depressive disorder.