Publications by authors named "Luke Harman"

10 Publications

  • Page 1 of 1

Cash transfers and child nutritional outcomes: a systematic review and meta-analysis.

BMJ Glob Health 2020 12;5(12)

Social Policy and Inclusion Section Programme Division, UNICEF, New York, New York, USA.

Background: Cash transfer (CT) programmes are implemented widely to alleviate poverty and provide safety nets to vulnerable households with children. However, evidence on the effects of CTs on child health and nutrition outcomes has been mixed. We systematically reviewed evidence of the impact of CTs on child nutritional status and selected proximate determinants.

Methods: We searched articles published between January 1997 and September 2018 using Agris, Econlit, Eldis, IBSS, IDEAS, IFPRI, Google Scholar, PubMed and World Bank databases. We included studies using quantitative impact evaluation methods of CTs with sample sizes over 300, targeted to households with children under 5 years old conducted in countries with gross domestic product per capita below US$10 000 at baseline. We conducted meta-analysis using random-effects models to assess the impact of CT programmes on selected child nutrition outcomes and meta-regression analysis to examine the association of programme characteristics with effect sizes.

Results: Out of 2862 articles identified, 74 articles were eligible for inclusion. We find that CTs have significant effects of 0.03±0.03 on height-for-age z-scores (p<0.03) and a decrease of 2.1% in stunting (95% CI -3.5% to -0.7%); consumption of animal-source foods (4.5%, 95% CI 2.9% to 6.0%); dietary diversity (0.73, 95% CI 0.28 to 1.19) and diarrhoea incidence (-2.7%, 95% CI -5.4% to -0.0%; p<0.05). The effects of CTs on weight-for-age z-scores and wasting were not significant (0.02, 95% CI -0.03 to 0.08; p<0.42) and (1.2%, 95% CI: -0.1% to 2.5%; p<0.07), respectively. We found that specific programme characteristics differentially modified the effect on the nutrition outcomes studied.

Conclusion: We found that CT programmes targeted to households with young children improved linear growth and contributed to reduced stunting. We found that the likely pathways were through increased dietary diversity, including through the increased consumption of animal-source foods and reduced incidence of diarrhoea. With heightened interest in nutrition-responsive social protection programmes to improve child nutrition, we make recommendations to inform the design and implementation of future programmes.
View Article and Find Full Text PDF

Download full-text PDF

Source
http://dx.doi.org/10.1136/bmjgh-2020-003621DOI Listing
http://www.ncbi.nlm.nih.gov/pmc/articles/PMC7751217PMC
December 2020

Metabolic traits in brown trout () vary in response to food restriction and intrinsic factors.

Conserv Physiol 2020 14;8(1):coaa096. Epub 2020 Oct 14.

School of Biological, Earth and Environmental Sciences, University College Cork, Distillery Fields, North Mall, Cork T23 TK30, Ireland.

Metabolic rates vary hugely within and between populations, yet we know relatively little about factors causing intraspecific variation. Since metabolic rate determines the energetic cost of life, uncovering these sources of variation is important to understand and forecast responses to environmental change. Moreover, few studies have examined factors causing intraspecific variation in metabolic flexibility. We explore how extrinsic environmental conditions and intrinsic factors contribute to variation in metabolic traits in brown trout, an iconic and polymorphic species that is threatened across much of its native range. We measured metabolic traits in offspring from two wild populations that naturally show life-history variation in migratory tactics (one anadromous, i.e. sea-migratory, one non-anadromous) that we reared under either optimal food or experimental conditions of long-term food restriction (lasting between 7 and 17 months). Both populations showed decreased standard metabolic rates (SMR-baseline energy requirements) under low food conditions. The anadromous population had higher maximum metabolic rate (MMR) than the non-anadromous population, and marginally higher SMR. The MMR difference was greater than SMR and consequently aerobic scope (AS) was higher in the anadromous population. MMR and AS were both higher in males than females. The anadromous population also had higher AS under low food compared to optimal food conditions, consistent with population-specific effects of food restriction on AS. Our results suggest different components of metabolic rate can vary in their response to environmental conditions, and according to intrinsic (population-background/sex) effects. Populations might further differ in their flexibility of metabolic traits, potentially due to intrinsic factors related to life history (e.g migratory tactics). More comparisons of populations/individuals with divergent life histories will help to reveal this. Overall, our study suggests that incorporating an understanding of metabolic trait variation and flexibility and linking this to life history and demography will improve our ability to conserve populations experiencing global change.
View Article and Find Full Text PDF

Download full-text PDF

Source
http://dx.doi.org/10.1093/conphys/coaa096DOI Listing
http://www.ncbi.nlm.nih.gov/pmc/articles/PMC7566963PMC
October 2020

Food and temperature stressors have opposing effects in determining flexible migration decisions in brown trout (Salmo trutta).

Glob Chang Biol 2020 05 27;26(5):2878-2896. Epub 2020 Feb 27.

School of Biological, Earth and Environmental Sciences, University College Cork, Cork, Ireland.

With rapid global change, organisms in natural systems are exposed to a multitude of stressors that likely co-occur, with uncertain impacts. We explored individual and cumulative effects of co-occurring environmental stressors on the striking, yet poorly understood, phenomenon of facultative migration. We reared offspring of a brown trout population that naturally demonstrates facultative anadromy (sea migration), under different environmental stressor treatments and measured life history responses in terms of migratory tactics and freshwater maturation rates. Juvenile fish were exposed to reduced food availability, temperatures elevated to 1.8°C above natural conditions or both treatments in combination over 18 months of experimental tank rearing. When considered in isolation, reduced food had negative effects on the size, mass and condition of fish across the experiment. We detected variable effects of warm temperatures (negative effects on size and mass, but positive effect on lipids). When combined with food restriction, temperature effects on these traits were less pronounced, implying antagonistic stressor effects on morphological traits. Stressors combined additively, but had opposing effects on life history tactics: migration increased and maturation rates decreased under low food conditions, whereas the opposite occurred in the warm temperature treatment. Not all fish had expressed maturation or migration tactics by the end of the study, and the frequency of these 'unassigned' fish was higher in food deprivation treatments, but lower in warm treatments. Fish showing migration tactics were smaller and in poorer condition than fish showing maturation tactics, but were similar in size to unassigned fish. We further detected effects of food restriction on hypo-osmoregulatory function of migrants that may influence the fitness benefits of the migratory tactic at sea. We also highlight that responses to multiple stressors may vary depending on the response considered. Collectively, our results indicate contrasting effects of environmental stressors on life history trajectories in a facultatively migratory species.
View Article and Find Full Text PDF

Download full-text PDF

Source
http://dx.doi.org/10.1111/gcb.14990DOI Listing
May 2020

Global spatial risk assessment of sharks under the footprint of fisheries.

Authors:
Nuno Queiroz Nicolas E Humphries Ana Couto Marisa Vedor Ivo da Costa Ana M M Sequeira Gonzalo Mucientes António M Santos Francisco J Abascal Debra L Abercrombie Katya Abrantes David Acuña-Marrero André S Afonso Pedro Afonso Darrell Anders Gonzalo Araujo Randall Arauz Pascal Bach Adam Barnett Diego Bernal Michael L Berumen Sandra Bessudo Lion Natalia P A Bezerra Antonin V Blaison Barbara A Block Mark E Bond Ramón Bonfil Russell W Bradford Camrin D Braun Edward J Brooks Annabelle Brooks Judith Brown Barry D Bruce Michael E Byrne Steven E Campana Aaron B Carlisle Demian D Chapman Taylor K Chapple John Chisholm Christopher R Clarke Eric G Clua Jesse E M Cochran Estelle C Crochelet Laurent Dagorn Ryan Daly Daniel Devia Cortés Thomas K Doyle Michael Drew Clinton A J Duffy Thor Erikson Eduardo Espinoza Luciana C Ferreira Francesco Ferretti John D Filmalter G Chris Fischer Richard Fitzpatrick Jorge Fontes Fabien Forget Mark Fowler Malcolm P Francis Austin J Gallagher Enrico Gennari Simon D Goldsworthy Matthew J Gollock Jonathan R Green Johan A Gustafson Tristan L Guttridge Hector M Guzman Neil Hammerschlag Luke Harman Fábio H V Hazin Matthew Heard Alex R Hearn John C Holdsworth Bonnie J Holmes Lucy A Howey Mauricio Hoyos Robert E Hueter Nigel E Hussey Charlie Huveneers Dylan T Irion David M P Jacoby Oliver J D Jewell Ryan Johnson Lance K B Jordan Salvador J Jorgensen Warren Joyce Clare A Keating Daly James T Ketchum A Peter Klimley Alison A Kock Pieter Koen Felipe Ladino Fernanda O Lana James S E Lea Fiona Llewellyn Warrick S Lyon Anna MacDonnell Bruno C L Macena Heather Marshall Jaime D McAllister Rory McAuley Michael A Meÿer John J Morris Emily R Nelson Yannis P Papastamatiou Toby A Patterson Cesar Peñaherrera-Palma Julian G Pepperell Simon J Pierce Francois Poisson Lina Maria Quintero Andrew J Richardson Paul J Rogers Christoph A Rohner David R L Rowat Melita Samoilys Jayson M Semmens Marcus Sheaves George Shillinger Mahmood Shivji Sarika Singh Gregory B Skomal Malcolm J Smale Laurenne B Snyders German Soler Marc Soria Kilian M Stehfest John D Stevens Simon R Thorrold Mariana T Tolotti Alison Towner Paulo Travassos John P Tyminski Frederic Vandeperre Jeremy J Vaudo Yuuki Y Watanabe Sam B Weber Bradley M Wetherbee Timothy D White Sean Williams Patricia M Zárate Robert Harcourt Graeme C Hays Mark G Meekan Michele Thums Xabier Irigoien Victor M Eguiluz Carlos M Duarte Lara L Sousa Samantha J Simpson Emily J Southall David W Sims

Nature 2019 08 24;572(7770):461-466. Epub 2019 Jul 24.

Marine Biological Association of the United Kingdom, Plymouth, UK.

Effective ocean management and the conservation of highly migratory species depend on resolving the overlap between animal movements and distributions, and fishing effort. However, this information is lacking at a global scale. Here we show, using a big-data approach that combines satellite-tracked movements of pelagic sharks and global fishing fleets, that 24% of the mean monthly space used by sharks falls under the footprint of pelagic longline fisheries. Space-use hotspots of commercially valuable sharks and of internationally protected species had the highest overlap with longlines (up to 76% and 64%, respectively), and were also associated with significant increases in fishing effort. We conclude that pelagic sharks have limited spatial refuge from current levels of fishing effort in marine areas beyond national jurisdictions (the high seas). Our results demonstrate an urgent need for conservation and management measures at high-seas hotspots of shark space use, and highlight the potential of simultaneous satellite surveillance of megafauna and fishers as a tool for near-real-time, dynamic management.
View Article and Find Full Text PDF

Download full-text PDF

Source
http://dx.doi.org/10.1038/s41586-019-1444-4DOI Listing
August 2019

Using tagging data and aerial surveys to incorporate availability bias in the abundance estimation of blue sharks (Prionace glauca).

PLoS One 2018 11;13(9):e0203122. Epub 2018 Sep 11.

School of Biological, Earth and Environmental Sciences, University College Cork, Cork, Ireland.

There is worldwide concern about the status of elasmobranchs, primarily as a result of overfishing and bycatch with subsequent ecosystem effects following the removal of top predators. Whilst abundant and wide-ranging, blue sharks (Prionace glauca) are the most heavily exploited shark species having suffered marked declines over the past decades, and there is a call for robust abundance estimates. In this study, we utilized depth data collected from two blue sharks using pop-up satellite archival tags, and modelled the proportion of time the sharks were swimming in the top 1-meter layer and could therefore be detected by observers conducting aerial surveys. The availability models indicated that the tagged sharks preferred surface waters whilst swimming over the continental shelf and during daytime, with a model-predicted average proportion of time spent at the surface of 0.633 (SD = 0.094) for on-shelf, and 0.136 (SD = 0.075) for off-shelf. These predicted values were then used to account for availability bias in abundance estimates for the species over a large area in the Northeast Atlantic, derived through distance sampling using aerial survey data collected in 2015 and 2016 and modelled with density surface models. Further, we compared abundance estimates corrected with model-predicted availability to uncorrected estimates and to estimates that incorporated the average time the sharks were available for detection. The mean abundance (number of individuals) corrected with modelled availability was 15,320 (CV = 0.28) in 2015 and 11,001 (CV = 0.27) in 2016. Depending on the year, these estimates were ~7 times higher compared to estimates without the bias correction, and ~3 times higher compared to the abundances corrected with average availability. When the survey area contains habitat heterogeneity that may affect surfacing patterns of animals, modelling animals' availability provides a robust alternative to correcting for availability bias and highlights the need for caution when applying "average" correction factors.
View Article and Find Full Text PDF

Download full-text PDF

Source
http://journals.plos.org/plosone/article?id=10.1371/journal.pone.0203122PLOS
http://www.ncbi.nlm.nih.gov/pmc/articles/PMC6133345PMC
February 2019

The impact of a mosquito net voucher subsidy programme on incremental ownership: The case of the Tanzania National Voucher Scheme.

Health Econ 2018 03 29;27(3):480-492. Epub 2017 Sep 29.

SOAS, University of London; LCIRAH, London, UK.

The subsidisation of mosquito nets has been widely used to increase ownership in countries where malaria represents a public health problem. However, an important question that has not been addressed empirically is how far net subsidy programmes increase ownership above the level that would have prevailed in the absence of the subsidy (i.e., incremental ownership). This study addresses that gap by investigating the impact of a large-scale mosquito net voucher subsidy--the Tanzania National Voucher Scheme (TNVS)--on short-term demand for unsubsidised commercial nets, estimating a household demand model with nationally representative household survey data. The results suggest that, despite the TNVS using a categorical targeting approach that did not discriminate by wealth, it still led to a large increase in incremental ownership of mosquito nets, with limited evidence of displacement of unsubsidised sales. Although no evidence is found of an additional TNVS voucher decreasing the number of unsubsidised sales in the same period, results indicate that an additional TNVS voucher reduced the probability of purchasing any unsubsidised net in the same period by 14%. The findings also highlight the critical role played by social learning or campaign messaging in increasing mosquito net ownership.
View Article and Find Full Text PDF

Download full-text PDF

Source
http://dx.doi.org/10.1002/hec.3587DOI Listing
March 2018

Gill damage to Atlantic salmon (Salmo salar) caused by the common jellyfish (Aurelia aurita) under experimental challenge.

PLoS One 2011 Apr 7;6(4):e18529. Epub 2011 Apr 7.

Coastal and Marine Research Centre, Environmental Research Institute, University College Cork, Cork, Ireland.

Background: Over recent decades jellyfish have caused fish kill events and recurrent gill problems in marine-farmed salmonids. Common jellyfish (Aurelia spp.) are among the most cosmopolitan jellyfish species in the oceans, with populations increasing in many coastal areas. The negative interaction between jellyfish and fish in aquaculture remains a poorly studied area of science. Thus, a recent fish mortality event in Ireland, involving Aurelia aurita, spurred an investigation into the effects of this jellyfish on marine-farmed salmon.

Methodology/principal Findings: To address the in vivo impact of the common jellyfish (A. aurita) on salmonids, we exposed Atlantic salmon (Salmo salar) smolts to macerated A. aurita for 10 hrs under experimental challenge. Gill tissues of control and experimental treatment groups were scored with a system that rated the damage between 0 and 21 using a range of primary and secondary parameters. Our results revealed that A. aurita rapidly and extensively damaged the gills of S. salar, with the pathogenesis of the disorder progressing even after the jellyfish were removed. After only 2 hrs of exposure, significant multi-focal damage to gill tissues was apparent. The nature and extent of the damage increased up to 48 hrs from the start of the challenge. Although the gills remained extensively damaged at 3 wks from the start of the challenge trial, shortening of the gill lamellae and organisation of the cells indicated an attempt to repair the damage suffered.

Conclusions: Our findings clearly demonstrate that A. aurita can cause severe gill problems in marine-farmed fish. With aquaculture predicted to expand worldwide and evidence suggesting that jellyfish populations are increasing in some areas, this threat to aquaculture is of rising concern as significant losses due to jellyfish could be expected to increase in the future.
View Article and Find Full Text PDF

Download full-text PDF

Source
http://journals.plos.org/plosone/article?id=10.1371/journal.pone.0018529PLOS
http://www.ncbi.nlm.nih.gov/pmc/articles/PMC3072396PMC
April 2011

Opening and closing mechanisms of the leatherback sea turtle larynx: a crucial role for the tongue.

J Exp Biol 2010 Dec;213(Pt 24):4137-45

Department of Anatomy, University College Cork, College Road, Cork, Ireland.

A combination of dissection and computed tomography scanning has provided significant novel insights into the structure and function of the Dermochelys coriacea larynx and its associated muscles. Several previously unknown features of the laryngeal aditus (glottis) are described and their functional significance in its opening and closure are considered. The tongue plays an essential part in producing and maintaining closure during dives and feeding bouts. Closure is brought about by compression of the glottis under the action of the two hyoglossus muscles. The tongue thus plays the role of the epiglottis of mammals, sealing the entrance to the larynx. As is already clear, opening is brought about by abduction of the arytenoid cartilages. In addition, there is a powerful mechanism for maintaining the larynx in close apposition to the hyoid plate during feeding and neck flexion, thereby enhancing the efficiency of feeding.
View Article and Find Full Text PDF

Download full-text PDF

Source
http://dx.doi.org/10.1242/jeb.042218DOI Listing
December 2010

Ontogenetic changes in tracheal structure facilitate deep dives and cold water foraging in adult leatherback sea turtles.

J Exp Biol 2009 Nov;212(Pt 21):3440-7

Department of Zoology, and Environmental Research Institute, University College Cork, Distillery Fields, North Mall, Cork, Ireland.

Adult leatherbacks are large animals (300-500 kg), overlapping in size with marine pinniped and cetacean species. Unlike marine mammals, they start their aquatic life as 40-50 g hatchlings, so undergo a 10,000-fold increase in body mass during independent existence. Hatchlings are limited to the tropics and near-surface water. Adults, obligate predators on gelatinous plankton, encounter cold water at depth (<1280 m) or high latitude and are gigantotherms that maintain elevated core body temperatures in cold water. This study shows that there are great ontogenetic changes in tracheal structure related to diving and exposure to cold. Hatchling leatherbacks have a conventional reptilian tracheal structure with circular cartilaginous rings interspersed with extensive connective tissue. The adult trachea is an almost continuous ellipsoidal cartilaginous tube composed of interlocking plates, and will collapse easily in the upper part of the water column during dives, thus avoiding pressure-related structural and physiological problems. It is lined with an extensive, dense erectile vascular plexus that will warm and humidify cold inspired air and possibly retain heat on expiration. A sub-luminal lymphatic plexus is also present. Mammals and birds have independently evolved nasal turbinates to fulfil such a respiratory thermocontrol function; for them, turbinates are regarded as diagnostic of endothermy. This is the first demonstration of a turbinate equivalent in a living reptile.
View Article and Find Full Text PDF

Download full-text PDF

Source
http://dx.doi.org/10.1242/jeb.034991DOI Listing
November 2009

Fat head: an analysis of head and neck insulation in the leatherback turtle (Dermochelys coriacea).

J Exp Biol 2009 Sep;212(17):2753-9

Department of Zoology, Ecology and Plant Science and Environmental Research Institute, University College Cork, Distillery Fields, North Mall, Cork, Ireland.

Adult leatherback turtles are gigantothermic/endothermic when foraging in cool temperate waters, maintaining a core body temperature within the main body cavity of ca. 25 degrees C despite encountering surface temperatures of ca. 15 degrees C and temperatures as low as 0.4 degrees C during dives. Leatherbacks also eat very large quantities of cold, gelatinous prey (medusae and pyrosomas). We hypothesised that the head and neck of the leatherback would have structural features to minimise cephalic heat loss and limit cooling of the head and neck during food ingestion. By gross dissection and analytical computed tomography (validated by ground truthing dissection) of an embalmed specimen we confirmed this prediction. 21% of the head and neck was occupied by adipose tissue. This occurred as intracranial blubber, encapsulating the salt glands, medial portions of the eyeballs, plus the neurocranium and brain. The dorsal and lateral surfaces of the neck featured thick blubber pads whereas the carotid arteries and jugular veins were deeply buried in the neck and protected laterally by blubber. The oesophagus was surrounded by a thick sheath of adipose tissue whereas the oropharyngeal cavity had an adipose layer between it and the bony proportion of the palate, providing further ventral insulation for salt glands and neurocranium.
View Article and Find Full Text PDF

Download full-text PDF

Source
http://dx.doi.org/10.1242/jeb.026500DOI Listing
September 2009