bluuebunny/crossref_metadata_2025_split huggingface dataset:
TEENAGE MOTHERHOOD AND INFANT MORTALITY IN BANGLADESH: MATERNAL AGE-DEPENDENT EFFECT OF PARITY ONE
Authors: ALAM NURUL 
Published: July 2002

Nuptiality norms in rural Bangladesh favour birth during the teenage years. An appreciable proportion of teenage births are, in fact, second births. This study examines the relationship between teenage fertility and high infant mortality. It is hypothesized that if physiological immaturity is responsible, then the younger the mother, the higher would be the mortality risk, and the effect of mother's ‘teenage’ on mortality in infancy, particularly in the neonatal period, would be higher for the second than the first births. Vital events recorded by the longitudinal demographic surveillance system in Matlab, Bangladesh, in 1990–92 were used. Logistic regression was used to estimate the effects on early and late neonatal (0–3 days and 4–28 days respectively) and post-neonatal mortality of the following variables: mother's age at birth, parity, education and religion, sex of the child, household economic status and exposure to a health intervention programme.The younger the mother, the higher were the odds of her child dying as a neonate, and the odds were higher for second children than first children of teenage mothers. First-born children were at higher odds of dying in infancy than second births if mothers were in their twenties. Unfavourable mother's socioeconomic conditions were weakly, but significantly, associated with higher odds of dying during late neonatal and post-neonatal periods. The results suggest that physical immaturity may be of major importance in determining the relationship between teenage fertility and high neonatal mortality.
Composition of the sterol fraction of caprine milk fat by gas chromatography and mass spectrometry
Authors: FRAGA MARÍA J. , FONTECHA JAVIER , LOZADA LUCIDIA , MARTÍNEZ-CASTRO ISABEL , JUÁREZ MANUELA 
Published: July 2002

The sterol fraction of milk is of nutritional interest because high levels of
cholesterol in plasma (modulated by the cholesterol ingested) are associated with an
increasing risk of cardiovascular disease. In addition, some sterols (ergosterol and
7-dehydrocholesterol) are provitamins (D2 and D3 respectively). At the same time,
through the study of the sterol fraction, vegetable fats can be detected in milk and
dairy products. Sterols are a minor fraction of total milk fat, the main sterol being
cholesterol (3 mg/g fat, equivalent to 100 mg/l cows' milk). Small quantities of other
sterols (7-dehydrocholesterol, 22-dehydrocholesterol, ergosterol, fucosterol, lanosterol,
lathosterol, 24-methylenecholesterol) and several phytosterols have been
reported in cows' milk (Walstra & Jennes, 1984). International Dairy Federation
(1992) states that in the sterol profile of genuine milk fat there may appear, in
addition to the peak of 7-dehydrocholesterol which ranges from 0·7 to 4% of total
sterols, < 1% of minor sterols with retention times corresponding to phytosterols.Values for the cholesterol content of goats' milk vary considerably, from
211 mg/l (Pantulu et al. 1975) to 125 mg/l (Lu, 1993), partly owing to the use of
different analysis techniques. Some of these values were obtained using non-specific
colorimetric methods, which are inaccurate in the presence of cholesterol precursors
or phytosterols (Clark et al. 1983; Haugh & Harzer, 1984). Some minor peaks have
been assumed to be sterols but have not been identified (García-Olmedo & Barrera,
1985).Conventional methods of sample preparation for sterol analysis prior to gas
chromatography (GC), which involve saponification of fat with or without isolation
of the sterol fraction by thin layer chromatography, are tedious and time-consuming.
Transesterification with KOH–methanol has been successfully used as a rapid
alternative for obtaining the unsaponifiable fraction.This paper describes the identification of sterols (cholesterol and other minor
sterols) in goats' milk fat using an alkali-catalysed transesterification procedure prior
to GC and GC–mass spectrometry (GC–MS) analysis.
Effect of various milking machine systems and components on free
fatty acid levels in milk
Authors: O'BRIEN BERNADETTE , O'CALLAGHAN EDMOND , DILLON PATRICK 
Published: July 2002

Elevated free fatty acid (FFA) levels in milk can impair the flavour
quality and
shelf life of milk and milk products and thus have implications for the
dairy industry.
An increase in milk FFA is induced when the protective fat globule membrane
is
disrupted and the fat exposed to the action of lipoprotein lipase (EC 3.1.1.34).

Various aspects of FFA development have been reviewed (Deeth & Fitz-Gerald,

1976; Fleming, 1979; International Dairy Federation, 1980). Mechanical
factors that
contribute to FFA development are directly related to poor milking systems
and
procedures (O'Halloran et al. 1975; Judge et al.

1977; Fleming, 1991). Mechanical
abuse of milk in many modern milking systems arises from air admission
to the
milking system, height of milklines and pump operation. Surveys and experience

(Fleming et al. 1996) showed that the quality of the components
used and the overall
maintenance of many milking machines was inadequate. In continental Europe
low-level
milking systems are generally recommended in preference to higher lines.

However, low-level systems are considerably more expensive as units have
to be
doubled up compared with the mid-level system.Some of the machine factors contributing to excessive FFA development
in milk
can be eliminated by proper design, installation, maintenance and operation;

however, the benefits of design changes remain a source of debate. The
purpose of
this investigation was to determine the relative effects on milk FFA of
various
components of a modern mid-level milking system (a pipeline milking system
with
the milkline 1·2–1·5m above cow standing level)
and then to compare the optimal
mid-level system with direct-to-line and low-level milking systems.
Protein A gene polymorphism analysis in Staphylococcus aureus
strains isolated from bovine subclinical mastitis
Authors: DALLA POZZA MARIA CRISTINA , RICCI ANTONIA , VICENZONI GADDO 
Published: July 2002

Mammary infections caused by Staphylococcus aureus are still one of the most
serious problems in dairy farms all over the world (Sischo et al. 1993), and the
epidemiology of the infection has not yet been completely elucidated (Aarestrup et
al. 1995). Any effective modern approach to this disease must therefore be based on
more comprehensive epidemiological studies, conducted with valid microbiological
typing tools.A technique for use in epidemiological studies should identify many types, and
should be inexpensive, quick and easy to perform, but above all reproducible. Among
the available methods, phage typing has up to now been widely and successfully used
in differentiating strains of Staph. aureus isolated from cattle with mastitis (Mackie
et al. 1987; Fox et al. 1991), but it has some limitations, being a technically
demanding method subject to considerable experimental as well as biological
variation (Maslow et al. 1993). Moreover, in some studies the number of strains that
could not be typed with available bacteriophage panels has been high (Carroll &
Francis, 1985; Farah et al. 1988).Alternative methods have been investigated, and of these molecular techniques
have been the most intensely studied (Aarestrup et al. 1995). In studies of human
infections caused by Staph. aureus, analysis of the so-called X region of protein A
gene polymorphism has been a useful epidemiological marker (Frénay et al. 1994).
This gene is ∼2150 bp and harbours some functionally distinct regions: an FC-binding region, the so-called X region and, at the C terminus, a sequence required for
cell wall attachment (Guss et al. 1984; Frénay
et al. 1994). The X region
polymorphism depends on the presence, within the region itself, of a varying number
of 24 bp repeats, highlighted by the amplification of this highly polymorphic DNA
region and its subsequent restriction fragment length polymorphism (RFLP)
analysis (Frénay et al. 1994).Human epidemic (MRSA) and non-epidemic methicillin-resistant Staph. aureus
(non-MRSA) strains, which both cause infections but have completely different
infection patterns, have been successfully distinguished by analysis of this
polymorphism (Frénay et al. 1994). However, protein A has been identified in only
93% of Staph. aureus strains isolated from bovine intramammary infections
(Poutrel & Ducelliez, 1979; Johne & Jarp, 1988).The aim of the present study was to determine whether the gene for protein A of
Staph. aureus (Spa) was present in Staph. aureus strains isolated from cases of
subclinical bovine mastitis. This was carried out using the polymerase chain reaction
(PCR), as suggested by Frénay et al. (1994). In addition, we have investigated the
genetic polymorphism related to the X region of the gene, by means of PCR
amplification and subsequent RFLP analysis. Finally we verified the stability of this
region after in vitro subculture.
Shear-flow instability in a rotating fluid
Authors: VAN DE KONIJNENBERG J. A. , NIELSEN A. H. , JUUL RASMUSSEN J. , STENUM B. 
Published: July 2002

The instability of a forced, circular shear layer in a rotating fluid has been studied
experimentally and numerically. The experiments were performed with a shallow layer
of water in a parabolic tank, in which it is possible to apply radial pumping and to
model a geophysical beta-effect. A shear layer was produced by a secondary rotation
of the central part of the parabolic vessel. In most experiments, the shear layer
takes on the appearance of a sequence of vortices, the number of which decreases
with increasing strength of the shear. A beta-effect may prevent the formation of a
steady vortex chain. Continuous pumping of fluid from the periphery to the centre
or vice versa leads to an azimuthal velocity field corresponding to a point vortex.
This azimuthal flow appears to stabilize the shear flow if it is opposite to the inner
rotation, and to be destabilizing otherwise.The numerical investigations consist of the solution of the quasi-geostrophic equation
in a geometry similar to the experimental situation and with a term modelling
the experimental forcing. Though the numerical computations are based on a two-dimensional model, they capture the essential features of the instability and the
resulting vortex structures.
Convection-driven dynamos in a rotating plane layer
Authors: JONES CHRIS A. , ROBERTS PAUL H. 
Published: July 2002

The plane layer Childress–Soward dynamo model, consisting of a rotating layer of
electrically conducting fluid between horizontal planes heated from below, is studied.
Solutions periodic in the horizontal directions are sought, with electrically insulating
boundary conditions applied. The large Prandtl number limit is used.Fully three-dimensional convection-driven dynamos have been studied numerically
for this problem. Both the kinematic and the magnetically saturated regimes are
studied, and a simple model of the dynamo mechanism is proposed. The dependence
of the dynamo on the Rayleigh number, Ekman number and diffusivity ratio is
studied, and the role of Taylor's constraint in low Ekman number convection-driven
dynamos is considered.
The shadow-politics of Wolofisation
Authors: O'Brien Donal Cruise 
Published: July 2002

The relationship between language and politics in the African post-colony remains obscure and underexamined. Here we withdraw into a
poorly lit area, an area of potentialities, where new political shapes
may
emerge as the outcome of half-conscious choices made by very large
numbers of people. Language choices in the first place: the expansion
of the Wolof language in Senegal, principally though far from
exclusively an urban phenomenon, is to be seen in a context where the
individual may speak several languages, switching linguistically from
one social situation to another. Such multilingualism is general in
Africa: the particularity of the Wolof case, at least in Senegal, is the

extent to which this language has spread, far beyond the boundaries of

core ethnicity, of a historical Wolof zone from the colonial or pre-colonial periods. And these individual language choices cast their
political shadow.The political consequences of this socio-linguistic phenomenon are as

yet indistinct, but to see a little more clearly one should in the second

place relate it to the subject of the politics of ethnicity. Language is
of
course an important element in any definition of ethnicity, and there is

an evident overlap; but the politics of language is also a distinguishable

subject in its own right. Where the assertion of ethnic identity can be

identified as a possible weapon in the individual's struggle for power

and recognition within the colonial and post-colonial state, the choice

of a language is that of the most effective code in the individual's
daily
struggle for survival. Language choice in such a setting may be less a

matter of assertion, the proud proclamation of an identity, than it is
one
of evasion, a more or less conscious blurring of the boundaries of
identity. And in Senegal the government itself by its inaction has
practised its own shadow-politics of procrastination.
Problems in extraction and spectrophotometric determination of chlorophyll from epilithic microbial biofilms: towards a standard method
Authors: Thompson R.C. , Tobin M.L. , Hawkins S.J. , Norton T.A. 
Published: July 2002

A variety of methods are available to extract chlorophyll from epilithic biofilms using solvents. The relative efficiency of these has not been determined simultaneously and there is no recognized standard procedure. In this paper techniques for sample collection, storage, preparation and extraction are reviewed and compared experimentally.Extraction of chlorophyll was incomplete unless biofilms were fully hydrated. This factor was highly significant for all the solvents tested, with at least three times more pigment being extracted from hydrated samples than from dry ones. Methanol was the most efficient solvent, releasing over 96% of the total chlorophyll during a single extraction; hot ethanol extracted 86%, while acetone extracted less than 50%. Sonicating samples during extraction did not release any additional pigment. Centrifuging to remove suspended material did not alter estimates and was not advantageous. Rugose rock surfaces released more chlorophyll than smooth ones. However, a simple method to quantify surface rugosity at an appropriate scale was not available.Based on these observations, a standard method for chlorophyll extractions from epilithic biofilms using 100% methanol at room temperature (20°C) is proposed. This technique requires considerably less supervision than previously preferred methods and gave a chlorophyll extract which was stable for 15 h.
Effects of olanzapine on cerebellar functional connectivity in schizophrenia measured by fMRI during a simple motor task
Authors: STEPHAN K. E. , MAGNOTTA V. A. , WHITE T. , ARNDT S. , FLAUM M. , O'LEARY D. S. , ANDREASEN N. C. 
Published: July 2002

Background. According to current theories, schizophrenia results from altered connectivity in brain circuits for fundamental cognitive operations. Consequently, the poorly understood mechanisms of neuroleptic treatment may be explainable by altered functional interactions within such networks. The ‘cognitive dysmetria’ model hypothesizes that one key structure in these circuits is the cerebellum. To investigate the effects of olanzapine on cerebellar functional connectivity (CFC), a seed-voxel correlation analysis (SVCA) was used in a functional magnetic resonance imaging (fMRI) study of a simple finger-tapping task.Methods. fMRI scans were obtained from six schizophrenic patients under both drug-free and olanzapine-treated conditions and from a matched control group of six healthy subjects at corresponding time points. SVCAs were performed for anatomically and functionally standardized seed voxels in the anterior cerebellum. SVCA results were then processed by three different randomization analyses.Results. The analyses revealed that olanzapine caused widespread changes of CFC, including prominent changes in prefrontal cortex and mediodorsal thalamus. Significant changes in motor structures were found after subtractions within both groups and may thus indicate repetition effects rather than drug effects. Olanzapine ‘normalized’ the patients' CFC patterns for the right, but not for the left cerebellum.Conclusion. Even for a simple motor task, olanzapine affects functional interactions between the cerebellum and many non-motor brain regions, including elements of the ‘cognitive dysmetria’ circuit. Altogether, our findings suggest that olanzapine has a stronger differential effect on neural activity in prefrontal cortex and thalamus than in motor structures.
A twin study of mortality after spousal bereavement
Authors: LICHTENSTEIN P. , GATZ M. , BERG S. 
Published: July 2002

Background. Previous research has shown an increased risk

of mortality after spousal bereavement,
with the highest risk in the first weeks or months closest to the loss.

One difficult issue in these
designs is appropriate covariates and control groups.Method. This study is based on 1993 pairs of twins discordant

for marital status and on 35860
married individuals from the Swedish Twin Registry born between 1886 and
1958 and followed for
marital and vital status between 1981 and 1993.Results. Spousal bereavement was a risk factor for mortality

for both men and women using the
still married co-twin as a control to the widowed proband, and
controlling for earlier health status
and health-related risk factors. The mortality risk was higher for young-old
(under 70 years)
individuals, and for recently widowed than for longer-term widowed. Young-old
women had a
pattern with increased mortality risk during the first years
after bereavement, but also a markedly
decreased risk if they survived 4 years after bereavement, as compared
to married women.Conclusions. The results support a causal effect of bereavement

on mortality. The decrease in risk
for long-term young-old women is congruent with reports by widows of psychological
growth after
bereavement, involving increased sense of mastery and competence
after learning to live in new sets
of circumstances following the loss of their husband.
Early sexual abuse and lifetime psychopathology:
a co-twin–control study
Authors: DINWIDDIE S. , HEATH A. C. , DUNNE M. P. , BUCHOLZ K. K. , MADDEN P. A. F. , SLUTSKE W. S. , BIERUT L. J. , STATHAM D. B. , MARTIN N. G. 
Published: July 2002

Background. This study was designed to determine lifetime prevalence of psychiatric disorders
among twins who reported childhood sexual abuse (CSA), and to compare these rates with those
among non-abused co-twins. The contribution of familial and individual-specific factors to reported
sexual abuse was also examined.Method. Information about lifetime psychopathology and substance use was obtained by structured
telephone interviews with 5995 Australian twins. Twins who reported a history of childhood sexual
abuse (CSA) were contrasted on lifetime psychopathology with subjects without such a history; in
addition, comparisons were made between same-sex twin pairs discordant for CSA.Results. A history of CSA was reported by 5·9% of the women and 2·5% of the men. In the sample
as a whole, those reporting CSA were more likely to receive lifetime diagnoses of major depression,
conduct disorder, panic disorder and alcoholism, and were more likely to report suicidal ideation
and a history of suicide attempt. Abused women, but not men, were also more likely to report social
phobia. When comparisons were restricted to non-abused co-twins, no differences in
psychopathology were seen. However, rates of major depression, conduct disorder and suicidal
ideation were higher if both co-twins were abused than if the respondent alone reported CSA.
Model-fitting indicated that shared environmental factors influenced risk for reported CSA in
women, but not in men.Conclusion. The association between CSA and psychopathology arises at least in part through the
influence of shared familial factors on both risk of victimization and risk of psychopathology.
A neuropsychological comparison of schizophrenia
and schizophrenia-like psychosis of epilepsy
Authors: MELLERS J. D. C. , TOONE B. K. , LISHMAN W. A. 
Published: July 2002

Background. The schizophrenia-like psychoses of epilepsy (SLPE) might represent a secondary
form of schizophrenia in which the pathology is relatively confined to the temporal lobe. To test this
possibility we have compared the neuropsychological profile of schizophrenia and SLPE. Our main
hypothesis was that both psychotic groups would show deficits of temporal lobe function but that
prefrontal impairment, as measured by tests of executive function, would be found only in the
primary schizophrenic group.Methods. Four groups were studied: (1) patients with SLPE (N = 25); (2) patients with epilepsy but
not psychiatric history (N = 24); (3) patients with schizophrenia (N = 22); and (4) healthy
volunteers (N = 24). Neuropsychological testing comprised measures of pre-morbid IQ, current
verbal and performance IQ, information processing, digit span, motor speed, verbal and visual
learning and memory, verbal fluency, the Wisconsin Card Sorting Task, the Stroop test and the trail
making task.Results. Patients with schizophrenia and those with SLPE had almost identical neuropsychological
profiles, with impairments of attention, episodic memory (verbal > visual) and executive function.
The epileptic controls showed similar though less severe impairments of memory and of some tests
of executive function.Conclusions. Our results do not support the hypothesis that the pathophysiology of SLPE and
schizophrenia are distinct. While our findings suggest an important role for dominant temporal lobe
abnormality in schizophrenia, both in its primary form and in that occurring in patients with
epilepsy, they also implicate generalized cognitive impairment, manifest in particular as attentional
deficits, in both forms of the disorder.
Social rhythm disruption and stressful life events in
the onset of bipolar and unipolar episodes
Authors: MALKOFF-SCHWARTZ S. , FRANK E. , ANDERSON B. P. , HLASTALA S. A. , LUTHER J. F. , SHERRILL J. T. , HOUCK P. R. , KUPFER D. J. 
Published: July 2002

Background. An association between social rhythm disruption (SRD) and
onset of manic episodes has recently been observed. Whether other types of bipolar
(depressive and cycling) or unipolar depressive episodes are similarly related to
SRD is unclear, as is the association between severely threatening life events and
onset of bipolar manic, depressed and cycling episodes.Methods. Bipolar patients with purely manic (N = 21), purely
depressed (N = 21) and cycling (N = 24) episodes, and 44 patients
with recurrent unipolar depression, were interviewed with the Bedford College Life
Events and Difficulties Schedule. The presence of severe and SRD events during the
year prior to index episode onset was then determined.Results. More manic than cycling and unipolar subjects experienced SRD
events during 8- and 20-week pre-onset periods, and severe events during 20-week
pre-onset periods. Controlling for age and prior number of episodes left most findings
unchanged. An earlier finding of more manic subjects with SRD events in an 8-week
pre-onset versus control period was also replicated.Conclusions. It appears that manic onsets are influenced by stressful
life events, especially those involving SRD, in a unique manner compared to onsets of
other types of bipolar and unipolar episodes. Onset of bipolar cycling episodes,
in contrast, seems to be relatively unaffected by SRD or severe life events.
These findings refine the hypothesis that SRD may precipitate onset of affective
episodes to be specific to manic onsets.