86 research outputs found
Amerisclerosis? The Puzzle of Rising U.S. Unemployment Persistence
The persistence of U.S. unemployment has risen with each of the last three recessions, raising the specter that future U.S. recessions might look more like the Eurosclerosis experience of the 1980s than traditional V-shaped recoveries of the past. In this paper, we revisit possible explanations for this rising persistence. First, we argue that financial shocks do not systematically lead to more persistent unemployment than monetary policy shocks, so these cannot explain the rising persistence of unemployment. Second, monetary and fiscal policies can account for only part of the evolving unemployment persistence. Therefore, we turn to a third class of explanations: propagation mechanisms. We focus on factors consistent with four other cyclical patterns which have evolved since the early 1980s: a rising cyclicality in long-term unemployment, lower regional convergence after downturns, rising cyclicality in disability claims, and missing disinflation. These factors include declining labor mobility, changing age structures, and the decline in trust among Americans. To determine how these factors affect unemployment persistence, this paper exploits regional variation in labor market outcomes across Western Europe and North America during 1970-1990, in contrast to most previous work focusing either on cross-country variation or regional variation within countries. The results suggest that only cultural factors can account for the rising persistence of unemployment in the U.S., but the evolution in mobility and demographics over time should have more than offset the effects of culture
Associations between Screen Time and Physical Activity among Spanish Adolescents
Excessive time in front of a single or several screens could explain a displacement of physical activity. The present study aimed at determining whether screen-time is associated with a reduced level of moderate to vigorous physical activity (MVPA) in Spanish adolescents living in favorable environmental conditions. or more to total screen-time showed a 64% (OR = 0.61, 95% CI, 0.44–0.86) increased risk of failing to achieve the recommended adolescent MVPA level. Participation in organized physical activities and sports competitions were more strongly associated with MVPA than screen-related behaviors.No single screen-related behavior explained the reduction of MVPA in adolescents. However, the total time accumulated through several screen-related behaviors was negatively associated with MVPA level in boys. This association could be due to lower availability of time for exercise as the time devoted to sedentary screen-time activities increases. Participation in organized physical activities seems to counteract the negative impact of excessive time in front of screens on physical activity
Clinical practice: Breastfeeding and the prevention of allergy
The increase in allergic disease prevalence has led to heightened interest in the factors determining allergy risk, fuelled by the hope that by influencing these factors one could reduce the prevalence of allergic conditions. The most important modifiable risk factors for allergy are maternal smoking behaviour and the type of feeding. A smoke-free environment for the child (to be), exclusive breastfeeding for 4–6 months and the postponement of supplementary feeding (solids) until 4 months of age are the main measures considered effective. There is no place for restricted diets during pregnancy or lactation. Although meta-analyses suggest that hypoallergenic formula after weaning from breastfeeding grants protection against the development of allergic disease, the evidence is limited and weak. Moreover, all current feeding measures aiming at allergy prevention fail to show effects on allergic manifestations later in life, such as asthma. In conclusion, the allergy preventive effect of dietary interventions in infancy is limited. Counselling of future parents on allergy prevention should pay attention to these limitations
Nanoscale Metallic Iron for Environmental Remediation: Prospects and Limitations
The amendment of the subsurface with nanoscale metallic iron particles
(nano-Fe0) has been discussed in the literature as an efficient in situ
technology for groundwater remediation. However, the introduction of this
technology was controversial and its efficiency has never been univocally
established. This unsatisfying situation has motivated this communication whose
objective was a comprehensive discussion of the intrinsic reactivity of
nano-Fe0 based on the contemporary knowledge on the mechanism of contaminant
removal by Fe0 and a mathematical model. It is showed that due to limitations
of the mass transfer of nano-Fe0 to contaminants, available concepts cannot
explain the success of nano-Fe0 injection for in situ groundwater remediation.
It is recommended to test the possibility of introducing nano-Fe0 to initiate
the formation of roll-fronts which propagation would induce the reductive
transformation of both dissolved and adsorbed contaminants. Within a
roll-front, FeII from nano-Fe0 is the reducing agent for contaminants. FeII is
recycled by biotic or abiotic FeIII reduction. While the roll-front concept
could explain the success of already implemented reaction zones, more research
is needed for a science-based recommendation of nano- Fe0 for subsurface
treatment by roll-front
Multi-messenger observations of a binary neutron star merger
On 2017 August 17 a binary neutron star coalescence candidate (later designated GW170817) with merger time 12:41:04 UTC was observed through gravitational waves by the Advanced LIGO and Advanced Virgo detectors. The Fermi Gamma-ray Burst Monitor independently detected a gamma-ray burst (GRB 170817A) with a time delay of ~1.7 s with respect to the merger time. From the gravitational-wave signal, the source was initially localized to a sky region of 31 deg2 at a luminosity distance of 40+8-8 Mpc and with component masses consistent with neutron stars. The component masses were later measured to be in the range 0.86 to 2.26 Mo. An extensive observing campaign was launched across the electromagnetic spectrum leading to the discovery of a bright optical transient (SSS17a, now with the IAU identification of AT 2017gfo) in NGC 4993 (at ~40 Mpc) less than 11 hours after the merger by the One- Meter, Two Hemisphere (1M2H) team using the 1 m Swope Telescope. The optical transient was independently detected by multiple teams within an hour. Subsequent observations targeted the object and its environment. Early ultraviolet observations revealed a blue transient that faded within 48 hours. Optical and infrared observations showed a redward evolution over ~10 days. Following early non-detections, X-ray and radio emission were discovered at the transient’s position ~9 and ~16 days, respectively, after the merger. Both the X-ray and radio emission likely arise from a physical process that is distinct from the one that generates the UV/optical/near-infrared emission. No ultra-high-energy gamma-rays and no neutrino candidates consistent with the source were found in follow-up searches. These observations support the hypothesis that GW170817 was produced by the merger of two neutron stars in NGC4993 followed by a short gamma-ray burst (GRB 170817A) and a kilonova/macronova powered by the radioactive decay of r-process nuclei synthesized in the ejecta
Polycomb repressive complex PRC1 spatially constrains the mouse embryonic stem cell genome.
The Polycomb repressive complexes PRC1 and PRC2 maintain embryonic stem cell (ESC) pluripotency by silencing lineage-specifying developmental regulator genes. Emerging evidence suggests that Polycomb complexes act through controlling spatial genome organization. We show that PRC1 functions as a master regulator of mouse ESC genome architecture by organizing genes in three-dimensional interaction networks. The strongest spatial network is composed of the four Hox gene clusters and early developmental transcription factor genes, the majority of which contact poised enhancers. Removal of Polycomb repression leads to disruption of promoter-promoter contacts in the Hox gene network. In contrast, promoter-enhancer contacts are maintained in the absence of Polycomb repression, with accompanying widespread acquisition of active chromatin signatures at network enhancers and pronounced transcriptional upregulation of network genes. Thus, PRC1 physically constrains developmental transcription factor genes and their enhancers in a silenced but poised spatial network. We propose that the selective release of genes from this spatial network underlies cell fate specification during early embryonic development
Neurocognitive correlates of obesity and obesity-related behaviors in children and adolescents.
Childhood obesity rates have risen dramatically over the past few decades. Although obesity has been linked to poorer neurocognitive functioning in adults, much less is known about this relationship in children and adolescents. Therefore, we conducted a systematic review to examine the relationship between obesity and obesity-related behaviors with neurocognitive functioning in youth. We reviewed articles from 1976 to 2013 using PsycInfo, PubMed, Medline and Google Scholar. Search terms included cognitive function, neurocognitive function/performance, executive function, impulsivity, self-regulation, effortful control, cognitive control, inhibition, delayed gratification, memory, attention, language, motor, visuo-spatial, academic achievement, obesity, overweight, body mass index, waist-hip ratio, adiposity and body fat. Articles were excluded if participants had health problems known to affect cognitive functioning, the study used imaging as the only outcome measure, they were non-peer-reviewed dissertations, theses, review papers, commentaries, or they were non-English articles. Sixty-seven studies met inclusion criteria for this review. Overall, we found data that support a negative relationship between obesity and various aspects of neurocognitive functioning, such as executive functioning, attention, visuo-spatial performance, and motor skill. The existing literature is mixed on the effects among obesity, general cognitive functioning, language, learning, memory, and academic achievement. Executive dysfunction is associated with obesity-related behaviors, such as increased intake, disinhibited eating, and less physical activity. Physical activity is positively linked with motor skill. More longitudinal research is needed to determine the directionality of such relationships, to point towards crucial intervention time periods in the development of children, and to inform effective treatment programs
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The relationship between parent feeding styles and general parenting with loss of control eating in treatment-seeking overweight and obese children
Objective To examine differences in parent feeding behaviors and general parenting of overweight children with and without loss of control (LOC) eating. Method One-hundred-and-eighteen overweight and obese children (10.40 ±-1.35 years; 53% female; 52% Caucasian; BMI-z: 2.06-±-0.39) and their parents (42.42-±-6.20 years; 91% female; 70% Caucasian; BMI: 31.74-±-6.96 kg/m ) were seen at a baseline assessment visit for a behavioral intervention that targeted overeating. The Eating Disorder Examination, adapted for children (ChEDE) was administered to assess for LOC eating. Parents completed the Parental Feeding Styles Questionnaire (PFSQ) and the Child Feeding Questionnaire (CFQ) to assess parent feeding styles and behaviors. Children also completed a self-report measure of general parenting (Child Report of Parent Behavior Inventory, CRPBI-30). Results Forty-three children (36.40%) reported at least one LOC eating episode in the month prior to assessment. Parents who reported greater restriction and higher levels of pressure to eat were more likely to have children that reported LOC eating (ps-<-0.05). Parents who utilized more instrumental feeding and prompting/encouragement to eat techniques were less likely to have children that reported LOC eating (ps-<-0.05). Child-reported parenting behaviors were unrelated to child LOC eating (ps > 0.05). Discussion Parent feeding styles and behaviors appear to be differentially and uniquely related to LOC eating in treatment-seeking overweight and obese children. Future research is needed to determine if implementing interventions that target parent feeding behaviors may reduce LOC eating, prevent full-syndrome eating disorders, and reduce weight gain in youth.
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