2,628 research outputs found
Agricultural Productivity and Anticipated Climate Change in Sub-Saharan Africa: A Spatial Sample Selection Model
A cereal yield response function is estimated conditional upon environmental and topographical features to detect the effects of spatial heterogeneity and spatial dependence in explaining agricultural productivity across Sub-Saharan Africa. Controlling for direct and localized spillover effects, we then estimate the effect that projected changes in temperature and precipitation as a result of global climate change will have on agricultural production. We find that the estimated declines found in the climatological literature may overestimate actual declines, and factors such as spatial heterogeneity (i.e., country fixed effects) are profoundly more important to agricultural production.Agricultural Production, Climate Change, Applied Spatial Econometrics, Sample Selection, Generalized Method of Moments Estimation, Environmental Economics and Policy, Productivity Analysis, I3, Q18, C50,
Vaccine hesitancy: clarifying a theoretical framework for an ambiguous notion.
Today, according to many public health experts, public confidence in vaccines is waning. The term "vaccine hesitancy" (VH) is increasingly used to describe the spread of such vaccine reluctance. But VH is an ambiguous notion and its theoretical background appears uncertain. To clarify this concept, we first review the current definitions of VH in the public health literature and examine its most prominent characteristics. VH has been defined as a set of beliefs, attitudes, or behaviours, or some combination of them, shared by a large and heterogeneous portion of the population and including people who exhibit reluctant conformism (they may either decline a vaccine, delay it or accept it despite their doubts) and vaccine-specific behaviours. Secondly, we underline some of the ambiguities of this notion and argue that it is more a catchall category than a real concept. We also call into question the usefulness of understanding VH as an intermediate position along a continuum ranging from anti-vaccine to pro-vaccine attitudes, and we discuss its qualification as a belief, attitude or behaviour. Thirdly, we propose a theoretical framework, based on previous literature and taking into account some major structural features of contemporary societies, that considers VH as a kind of decision-making process that depends on people's level of commitment to healthism/risk culture and on their level of confidence in the health authorities and mainstream medicine
Smart subsidies for sustainable soils: Evidence from a randomized controlled trial in southern Malawi
Conventional agricultural practices – especially conventional tillage – are a major driver of soil erosion globally. While soil may not frequently considered a vulnerable natural resource, the erosion and degradation of soils poses a serious threat to food production and the production of numerous otherin situ andex situ ecosystem services. This study provides some of the first evidence on the effectiveness of a payments for ecosystem services (PES) program to encourage the adoption of soil conservation practices, specifically conservation agriculture (CA). Through minimized soil disturbance, permanent soil cover, and diversified crop mix, CA is believed to enhance soil fertility and rehabilitate soil structure, with the resulting preservation of ecosystem service flows. By providing calibrated financial incentives, we demonstrate that it is possible to substantially increase the extent and intensity of CA adoption. What is more, we show that a novel incentive mechanisms that leverages social networks for the consolidation of fragmented land may be more effective at bringing more land under conservation objectives, even if some of the additional land does not officially fall under the purview of the PES program. We also demonstrate that some of the supposed weaknesses hindering the adoption of CA – lower yields in the short-run and higher expenditures on weed control – were not necessarily obstacles in our study area, perhaps suggesting that the provision of subsidies need not continue into perpetuity, but may only be needed to overcome short-term transition costs.https://www.sciencedirect.com/science/article/pii/S0095069621001108Published versio
Inductively Heated Shape Memory Polymer for the Magnetic Actuation of Medical Devices
Submitted to IEEE Trans. Biomed. Eng.Presently there is interest in making medical devices such as expandable stents and intravascular microactuators from shape memory polymer (SMP). One of the key challenges in realizing SMP medical devices is the implementation of a safe and effective method of thermally actuating various device geometries in vivo. A novel scheme of actuation by Curie-thermoregulated inductive heating is presented. Prototype medical devices made from SMP loaded with Nickel Zinc ferrite ferromagnetic particles were actuated in air by applying an alternating magnetic field to induce heating. Dynamic mechanical thermal analysis was performed on both the particle-loaded and neat SMP materials to assess the impact of the ferrite particles on the mechanical properties of the samples. Calorimetry was used to quantify the rate of heat generation as a function of particle size and volumetric loading of ferrite particles in the SMP. These tests demonstrated the feasibility of SMP actuation by inductive heating. Rapid and uniform heating was achieved in complex device geometries and particle loading up to 10% volume content did not interfere with the shape recovery of the SMP.Lawrence Livermore National Lab
Fundamental constructs in food parenting practices: a content map to guide future research
Although research shows that “food parenting practices” can impact children’s diet and eating habits, current understanding of the impact of specific practices has been limited by inconsistencies in terminology and definitions. This article represents a critical appraisal of food parenting practices, including clear terminology and definitions, by a working group of content experts. The result of this effort was the development of a content map for future research that presents 3 overarching, higher-order food parenting constructs – coercive control, structure, and autonomy support – as well as specific practice subconstructs. Coercive control includes restriction, pressure to eat, threats and bribes, and using food to control negative emotions. Structure includes rules and limits, limited/guided choices, monitoring, meal- and snacktime routines, modeling, food availability and accessibility, food preparation, and unstructured practices. Autonomy support includes nutrition education, child involvement, encouragement, praise, reasoning, and negotiation. Literature on each construct is reviewed, and directions for future research are offered. Clear terminology and definitions should facilitate cross-study comparisons and minimize conflicting findings resulting from previous discrepancies in construct operationalization
Understory 2014
“Art is the struggle to be, in a particular sort
of way, virtuous.” —Iris Murdoch
Indeed, when we embark on any creative adventure
it is with the purpose of conveying a certain truth; an
emotion, an idea that brings us together and reminds us
of the innate consciousness that dwells within.
Understory is emblematic of this; where individuals
intent on honing their craft can join others to become a
part of something greater, their work immortalized to
become a time capsule. Decades from now a volume of
Understory may be discovered on a dusty bookshelf in
some forgotten corner and the lucky explorer who finds it
shall be enlightened by pages of gold.
We, as editors of Understory 2014, have worked
very hard this year to put together a journal that showcases
the very best of the University of Alaska Anchorage
undergraduate student work. We hope you enjoy your
journey through this issue as much as we have enjoyed ours.
Thank you to the English and Art Departments,
for the staff and faculty’s unerring support of our club;
to Provost Baker, for seeing and believing in the vision
of Understory; and to our club’s faculty advisor, Douglass
Bourne, for his guidance and tireless assistance. Finally,
thank you to the wonderful students who submit such
excellent work each year. Without your passion for the
arts, we would not be here.Staff / Letter from the Editors / Glass Blower / Writing / Obsolete Evolution / Permafrost / Phoenix / Untitled / Ratio / Tripping / Abiogenesis / My Heart Beats for You / Meeting of the Fingerprint Lines / You Are No Stranger / Nightmare Fuel / Cane-Sugar / Gossamer Strands / Panthera Gold / Butterfly / A Mantis Too Far / Long and Winding Road / Chasing Shadows / Merisunas / Chequer Grove / Modzilla / Beans / Little Red and Mr. Wolf / In Memoriam, Joel Fletcher Armstrong / Glance / Courage / Uranium Waltz / Danger / Journey to the West / Antumbra / Roaring Like a Lion / Pre-boarding / Untitled / How Do You Say a Word / Fishing for Doom/ Contributor
Mandibulofacial Dysostosis Attributed to a Recessive Mutation of CYP26C1 in Hereford Cattle
In spring 2020, six Hereford calves presented with congenital facial deformities attributed to a condition we termed mandibulofacial dysostosis (MD). Affected calves shared hallmark features of a variably shortened and/or asymmetric lower mandible and bilateral skin tags present 2–10 cm caudal to the commissure of the lips. Pedigree analysis revealed a single common ancestor shared by the sire and dam of each affected calf. Whole-genome sequencing (WGS) of 20 animals led to the discovery of a variant (Chr26 g. 14404993T\u3eC) in Exon 3 of CYP26C1 associated with MD. This missense mutation (p.L188P), is located in an α helix of the protein, which the identified amino acid substitution is predicted to break. The implication of this mutation was further validated through genotyping 2 additional affected calves, 760 other Herefords, and by evaluation of available WGS data from over 2500 other individuals. Only the a_ected individuals were homozygous for the variant and all heterozygotes had at least one pedigree tie to the suspect founder. CYP26C1 plays a vital role in tissue-specific regulation of retinoic acid (RA) during embryonic development. Dysregulation of RA can result in teratogenesis by altering the endothelin-1 signaling pathway affecting the expression of Dlx genes, critical to mandibulofacial development. We postulate that this recessive missense mutation in CYP26C1 impacts the catalytic activity of the encoded enzyme, leading to excess RA resulting in the observed MD phenotype
- …