6,827 research outputs found
Insights from Project FeederWatch: Changes in the abundance and occurrence of birds in New Hampshire over the past 24 years
Changes in the climate and land use over time can lead to changes in the composition of wildlife communities. Using data from Project FeederWatch, we examine trends in the abundance and occurrence of birds documented in the winters from 1988 to 2012 in New Hampshire. Changes in abundance and occurrence are summarized for individual bird species as well as across species based on life history traits. In addition, we examined trends for the state as a whole as well as in subregions. We discuss these changes with regards to the variations of climate and land use that are occurring throughout New Hampshire
Solitons, Links and Knots
Using numerical simulations of the full nonlinear equations of motion we
investigate topological solitons of a modified O(3) sigma model in three space
dimensions, in which the solitons are stabilized by the Hopf charge. We find
that for solitons up to charge five the solutions have the structure of closed
strings, which become increasingly twisted as the charge increases. However,
for higher charge the solutions are more exotic and comprise linked loops and
knots. We discuss the structure and formation of these solitons and demonstrate
that the key property responsible for producing such a rich variety of solitons
is that of string reconnection.Comment: 24 pages plus 14 figures in GIF forma
Health and development of children born after assisted reproductive technology and sub-fertility compared to naturally conceived children: data from a national study
In a non-matched case-control study using data from two large national cohort studies, we investigated whether indicators of child health and development up to 7 years of age differ between children conceived using assisted reproductive technology (ART), children born after sub-fertility (more than 24 months of trying for conception) and other children. Information on ART use/sub-fertility was available for 23,649 children. There were 227 cases (children conceived through ART) and two control groups: 783 children born to sub-fertile couples, and 22,639 children born to couples with no fertility issues. In models adjusted for social and demographic factors there were significant differences between groups in rate of hospital admissions before the children were 9 months old (P=0.029), with the ART group showing higher rates of hospital admission than the no fertility issues control group, the sub-fertile control group being intermediate between the two. Children born after ART had comparable health and development beyond 9 months of age to their naturally conceived peers. This applied to the whole sample and to a sub-sample of children from deprived neighborhoods
Health outcomes of children born to mothers with chronic kidney disease: a pilot study
This study aimed to study the health of children born to mothers with chronic kidney disease. Twenty-four children born to mothers with chronic kidney disease were compared with 39 matched control children born to healthy mothers without kidney disease. The well-being of each child was individually assessed in terms of physical health, neurodevelopment and psychological health. Families participating with renal disease were more likely to be from lower socio-economic backgrounds. Significantly fewer vaginal deliveries were reported for mothers with renal disease and their infants were more likely to experience neonatal morbidity. Study and control children were comparable for growth parameters and neurodevelopment as assessed by the Griffiths scales. There was no evidence of more stress amongst mothers with renal disease or of impaired bonding between mother and child when compared to controls. However, there was evidence of greater externalizing behavioral problems in the group of children born to mothers with renal disease. Engaging families in such studies is challenging. Nonetheless, families who participated appreciated being asked. The children were apparently healthy but there was evidence in this small study of significant antenatal and perinatal morbidity compared to controls. Future larger multi-center studies are required to confirm these early findings
The Vampire and the FOOL
This paper presents new features recently implemented in the theorem prover
Vampire, namely support for first-order logic with a first class boolean sort
(FOOL) and polymorphic arrays. In addition to having a first class boolean
sort, FOOL also contains if-then-else and let-in expressions. We argue that
presented extensions facilitate reasoning-based program analysis, both by
increasing the expressivity of first-order reasoners and by gains in
efficiency
Multi-soliton dynamics in the Skyrme model
We exhibit the dynamical scattering of multi-solitons in the Skyrme model for
configurations with charge two, three and four. First, we construct maximally
attractive configurations from a simple profile function and the product
ansatz. Then using a sophisticated numerical algorithm, initially
well-separated skyrmions in approximately symmetric configurations are shown to
scatter through the known minimum energy configurations. These scattering
events illustrate a number of similarities to BPS monopole configurations of
the same charge. A simple modification of the dynamics to a dissipative regime,
allows us to compute the minimal energy skyrmions for baryon numbers one to
four to within a few percent.Comment: latex, 10 pages, plus 5 figures (as gif files
Drape optimization in woven composites manufacture.
This paper addresses the optimisation of forming in manufacturing of composites.
A simplified finite element model of draping is developed and implemented. The
model incorporates the non-linear shear response of textiles and wrinkling due
to buckling of tows. The model is validated against experimental results and it
is concluded that it reproduces successfully the most important features of the
process. The simple character of the model results in low computational times
that allow its use within an optimisation procedure. A genetic algorithm is used
to solve the optimisation problem of minimising the wrinkling in the formed
component by selecting a suitable holding force distribution. The effect of
regularisation is investigated and the L-curve is used to select a
regularisation parameter value. Optimised designs resulting from the inversion
procedure have significantly lower wrinkling than uniform holding force
profiles, while regularisation allows force gradients to be kept relatively low
so that suggested process designs are feasible
The health and development of children born to older mothers in the United Kingdom: observational study using longitudinal cohort data
Objective: To assess relations between children’s health and development and maternal age.
Design: Observational study of longitudinal cohorts.
Setting: Millennium Cohort Study (a random sample of UK children) and the National Evaluation of Sure Start study (a random sample of children in deprived areas in England), 2001 to 2007.
Participants: 31 257 children at age 9 months, 24 781 children at age 3 years, and 22 504 at age 5 years.
Main outcome measures: Childhood unintentional injuries and hospital admissions (aged 9 months, 3 years, and 5 years), immunisations (aged 9 months and 3 years), body mass index, language development, and difficulties with social development (aged 3 and 5 years).
Results: Associations were independent of personal and family characteristics and parity. The risk of children having unintentional injuries requiring medical attention or being admitted to hospital both declined with increasing maternal age. For example, at three years the risk of unintentional injuries declined from 36.6% for mothers aged 20 to 28.6% for mothers aged 40 and hospital admissions declined, respectively, from 27.1% to 21.6%. Immunisation rates at nine months increased with maternal age from 94.6% for mothers aged 20 to 98.1% for mothers aged 40. At three years, immunisation rates reached a maximum, at 81.3% for mothers aged 27, being lower for younger and older mothers. This was linked to rates for the combined measles, mumps, and rubella immunisation because excluding these resulted in no significant relation with maternal age. An increase in overweight children at ages 3 and 5 years associated with increasing maternal age was eliminated once maternal body mass index was included as a covariate. Language development was associated with improvements with increasing maternal age, with scores for children of mothers aged 20 being lower than those of children of mothers aged 40 by 0.21 to 0.22 standard deviations at ages 3 and 4 years. There were fewer social and emotional difficulties associated with increasing maternal age. Children of teenage mothers had more difficulties than children of mothers aged 40 (difference 0.28 SD at age 3 and 0.16 SD at age 5).
Conclusion: Increasing maternal age was associated with improved health and development for children up to 5 years of age
BRAND EXTENSIONS IN CONFECTIONARY; THE MARS DELIGHT
The concept of brand extension has been considered for several decades, drawing of work by Tauber (1981). Effective branding requires an understanding of areas such as segmentation, targeting and positioning which are critical in developing a successful brand management strategy. This research has focused on the unique nature of the highly competitive confectionery market, looking at recent brand activity by Masterfoods with emphasis on the launch of the Mars Delight, a brand extension recently launched in the UK and Ireland. The methodology utilised both qualitative and quantitative techniques to satisfy the research objectives. Initially the core purpose of this study was to investigate the alternative brand strategies available to drive growth in the competitive UK confectionery market. However, in conducting the initial research it became apparent that a particular model used as a basis to support brand strategy development was not adequate for this highly competitive, dynamic market sector. Therefore this study strove for a better understanding of brand management with the aim of providing an updated framework to guide brand strategy. The proposed Jigsaw Brand Matrix aims to extend the existing literature on brand portfolio strategy, and is hoped that it will be a valuable contribution to marketing theory
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