807 research outputs found
Methods, results and policy implications of poverty and food security mapping assessments
The importance of poverty reduction to the world development agenda has motivated greater interest in the geographic dimensions of poverty and food security. This special issue of Food Policy includes examples of poverty and food security mapping used to support policy development in agricultural and rural areas. The volume includes eight country case studies and one cross-country comparison that illustrate advances in our capacity to assess welfare over large areas and at detailed spatial resolutions. Poverty mapping facilitates assessments of the role of environmental factors on the broad spatial pattern of poverty and food security. Evaluating proximity and accessibility in welfare outcomes can improve our knowledge of poverty patterns and processes. Spatial statistics can enhance our understanding of geographic and neighbourhood effects on poverty and food security outcomes. The development of effective policies requires increased collaboration among stakeholders, researchers and policy makers in constructing and using poverty and food security maps
Phase Transition Study of Superconducting Microstructures
The presented results are part of a feasibility study of superheated
superconducting microstructure detectors. The microstructures (dots) were
fabricated using thin film patterning techniques with diameters ranging from
m up to m and thickness of m. We used arrays and single
dots to study the dynamics of the superheating and supercooling phase
transitions in a magnetic field parallel to the dot surface. The phase transi-
tions were produced by either varying the applied magnetic field strength at a
constant temperature or changing the bath temperature at a constant field.
Preliminary results on the dynamics of the phase transitions of arrays and
single indium dots will be reported.Comment: 7pages in LaTex format, five figures available upon request by
[email protected], preprint Bu-He 93/
How different experimental models of secondary hyperalgesia change the nociceptive flexion reflex
In this neurophysiological study in healthy humans, we assessed how central sensitization induced by either high-frequency stimulation (HFS) or topical capsaicin application modulates features of the RIII reflex response. The ability of these stimuli to engage the endogenous pain modulatory system was also tested. In 26 healthy participants we elicited an RIII reflex using suprathreshold stimulation of the sural nerve. Subsequently HFS or capsaicin were applied to the foot and the RIII reflex repeated after 15 minutes. Contact heating of the volar forearm served as the heterotopic test stimulus to probe activation of the endogenous pain modulatory system. HFS significantly reduced the pain threshold by 29% and the RIII reflex threshold by 20%. Capsaicin significantly reduced the pain threshold by 17% and the RIII reflex threshold by 18%. Both HFS and capsaicin left RIII reflex size unaffected. Numerical Rating Scale (NRS) pain scores elicited by the heterotopic noxious heat stimulus were unaffected by capsaicin and slightly increased by HFS. HFS and capsaicin similarly modulated the pain threshold and RIII reflex threshold, without a concomitant inhibitory effect of the endogenous pain modulatory system. Our neurophysiological study supports the use of the RIII reflex in investigating central sensitization in humans
Human fertilization: epididymal hCRISP1 mediates sperm zona pellucida binding through its interaction with ZP3
Human epididymal CRISP1 (hCRISP1) associates with sperm during maturation and participates in gamete fusion through egg complementary sites. Its homology with both rodent epididymal CRISP1 and CRISP4 reported to participate in the previous stage of sperm binding to the zona pellucida (ZP), led us to further investigate the functional role of hCRISP1 by studying its involvement in human sperm-ZP interaction. Human hemizona (HZ) were inseminated with human capacitated sperm in the presence of either anti-hCRISP1 polyclonal antibody to inhibit sperm hCRISP1, or bacterially-expressed hCRISP1 (rec-hCRISP1) to block putative hCRISP1 binding sites in the ZP. Results revealed that both anti-hCRISP1 and rec-hCRISP1 produced a significant inhibition in the number of sperm bound per HZ compared with the corresponding controls. The finding that neither anti-hCRISP1 nor rec-hCRISP1 affected capacitation-associated events (i.e. sperm motility, protein tyrosine phosphorylation or acrosome reaction) supports a specific inhibition at the sperm?egg interaction level. Moreover, immunofluorescence experiments using human ZP-intact eggs revealed the presence of complementary sites for hCRISP1 in the ZP. To identify the ligand of hCRISP1 in the ZP, human recombinant proteins ZP2, ZP3 and ZP4 expressed in insect cells were co-incubated with hCRISP1 and protein?protein interaction was analyzed by ELISA. Results revealed that rec-hCRISP1 mainly interacted with ZP3 in a dose-dependent and saturable manner, supporting the specificity of this interaction. Altogether, these results indicate that hCRISP1 is a multifunctional protein involved notonly in sperm?egg fusion but also in the previous stage of sperm?ZP binding through its specific interaction with human ZP3.Fil: Maldera, Julieta Antonella. Consejo Nacional de Investigaciones CientĂficas y TĂ©cnicas. Instituto de BiologĂa y Medicina Experimental (i); Argentina. Heidelberg University. Center for Molecular Biology; AlemaniaFil: Weigel Muñoz, Mariana. Consejo Nacional de Investigaciones CientĂficas y TĂ©cnicas. Instituto de BiologĂa y Medicina Experimental (i); ArgentinaFil: Chirinos, M.. Instituto Nacional de Ciencias MĂ©dicas y NutriciĂłn Salvador Zubiran; MĂ©xicoFil: Busso, Dolores. Pontificia Universidad CatĂłlica de Chile; Chile. Consejo Nacional de Investigaciones CientĂficas y TĂ©cnicas. Instituto de BiologĂa y Medicina Experimental (i); ArgentinaFil: Raffo, F. G. E.. Centro MĂ©dico Fertilab; ArgentinaFil: Battistone, Maria Agustina. Consejo Nacional de Investigaciones CientĂficas y TĂ©cnicas. Instituto de BiologĂa y Medicina Experimental (i); ArgentinaFil: Blaquier, J. A.. Centro MĂ©dico Fertilab; ArgentinaFil: Larrea, F.. Instituto Nacional de Ciencias MĂ©dicas y NutriciĂłn Salvador Zubiran; MĂ©xicoFil: Cuasnicu, Patricia Sara. Consejo Nacional de Investigaciones CientĂficas y TĂ©cnicas. Instituto de BiologĂa y Medicina Experimental (i); Argentin
CaracterizaciĂłn de las explotaciones lecheras de La Pampa
En la cuenca lechera de la provincia de la Pampa, al igual que en el resto de las cuencas argentinas, existe un proceso de concentraciĂłn de la producciĂłn, con reducciĂłn en la cantidad de establecimientos y aumento de la producciĂłn de leche. El conocimiento de la variabilidad de la estructura productiva como indicador estratĂ©gico permitirá implementar acciones de investigaciĂłn y desarrollo para la permanencia de las explotaciones en el sector lechero. El objetivo de este trabajo fue caracterizar la estructura productiva de los establecimientos lecheros de la provincia de La Pampa. Durante el año 2017, se encuestaron 45 explotaciones distribuidos en las tres cuencas, norte, centro y sur de la provincia de La Pampa. En promedio las explotaciones lecheras producen 3.509,82 Lts/dĂa ± 1.040,61 (C.V. 198,89%) en una superficie ganadera de 215,20 ha ± 57,90 (C.V.180,47%) con un total de vacas de 201,78 ± 58,00 (C.V. 192,83%). La mortalidad en la crĂa fue de 5,42% ± 0,38 (C.V. 47,26) superior al 3% recomendado y la edad al primer parto de 26,6 meses ± 0,35 (C.V. 8,87) levemente superior al intervalo de 24 – 26 meses destacado como Ăłptimo para no acrecentar los costos por tiempo ocioso. La producciĂłn de leche hallada concuerda con un sistema de producciĂłn pastoril, como el que predomina en La Pampa, con variables factibles de mejorar tales como las halladas en mortandad de la crĂa y edad al primer part
Dictyota chalchicueyecanensis sp. nov. (Dictyotales, Phaeophyceae) en el Golfo de MĂ©xico: evidencias moleculares y morfolĂłgicas
Background. Species of the Dictyota genus have a high phenotypic plasticity that contrasts with their limited morphological diagnostic characteristics, which has led to some uncertainty in identifying species in the Gulf of Mexico. Recent studies worldwide have focused on Dictyota species phylogenies, which are the basis for contrasting and interpreting the results of this study. Goals. In our research, we found evidence of a new species belonging to the Dictyota genus in three localities in the state of Veracruz, Mexico (Playa Hermosa, Punta Puntillas y Villa Rica). Methods. Phylogenetic andmolecular analyses of partial sequences of the psbA and cox1 genes were performed, complemented by morphological analysis. Results. In phylogenetic analysis of partial sequences of psbA and cox1, we established that samples of the new species form a well-supported monophyletic clade. In addition, the genetic divergence values that were obtained are within the interspecific values for the genus, allowing us to segregate the Dictyota chalchicueyecanensis sp. nov. from therest of the species of this genus. Morphologically this new species is characterized by an erect thallus, light brown and lacking iridescence, stiff to the touch, with a discoid holdfast, rounded apices, dichotomous branching, dentated margins, with minute teeth, triangular to spinose in shape that are directed toward the apices. Sporangia are isolated or grouped on both sides of the thallus and germinate regularly in interdichotomous basal portions. Conclusion. These results allow us to expand the diversity of the genus Dictyota worldwide, incorporating D. chalchicueyecanensis as a probable newspecies endemic to Mexico.Antecedentes. Las especies del gĂ©nero Dictyota presentan una alta plasticidad fenotĂpica que contrasta con escasos caracteres morfolĂłgicos diagnĂłsticos, lo cual ha llevado a identificar especies con cierta incertidumbre en el Golfo de MĂ©xico. Estudios recientes a nivel mundial refieren filogenias de especies de Dictyota, los que serán la base para contrastar e interpretar los resultados de este estudio. Objetivos. En este trabajo se determina la presencia de una nueva especie para la ciencia del gĂ©nero Dictyota, encontrada en tres localidades del estado de Veracruz, MĂ©xico (Playa Hermosa, Punta Puntillas y Villa Rica). MĂ©todos. Se realizaron análisis filogenĂ©ticos y moleculares de secuencias parciales de los genes psbA y cox1, que fueron complementados con análisis morfolĂłgicos. Resultados. En los análisis filogenĂ©ticos de las secuencias parciales de los genes psbA y cox1, se obtuvo que las muestras de la nueva especie forman un clado monofilĂ©tico bien soportado. Además, los Ăndices de divergencia genĂ©tica obtenidos, se encuentran dentro de los valores interespecĂficos para el gĂ©nero, lo que permite segregar a Dictyota chalchicueyecanensis sp. nov. de las demás especies del gĂ©nero. MorfolĂłgicamente esta nueva especie se caracteriza por presentar un talo erecto, sin iridiscencia, de consistencia rĂgida al tacto, con pie de fijaciĂłn al sustrato de forma discoide, de color cafĂ© claro in situ, ápices redondeados, amificaciĂłn dicotĂłmica, con márgenes dentados de forma triangular a espinosa dirigidos hacia los ápices. Esporangios aislados o agrupados en ambas superficies del talo que regularmente germinan en las porciones interdicotĂłmicas basales del mismo. Conclusiones. Los resultados anteriores amplĂan la diversidad del gĂ©nero Dictyota a nivel mundial, incorporando a D. chalchicueyecanensis como una nueva especie probablemente endĂ©mica de MĂ©xico
The evolution of Omega(HI) and the epoch of formation of damped Lyman-alpha absorbers
We present a study of the evolution of the column density distribution,
f(N,z), and total neutral hydrogen mass in high-column density quasar absorbers
using candidates from a recent high-redshift survey for damped Lyman-alpha
(DLA) and Lyman limit system (LLS) absorbers. The observed number of LLS
(N(HI)> 1.6 * 10^{17} atom/cm^2) is used to constrain f(N,z) below the
classical DLA Wolfe et al. (1986) definition of 2 * 10^{20} atom/cm^2. The
joint LLS-DLA analysis shows unambiguously that f(N,z) deviates significantly
from a single power law and that a Gamma-law distribution of the form
f(N,z)=(f_*/N_*)(N/N_*)^{-Beta} exp(-N/N_*) provides a better description of
the observations. These results are used to determine the amount of neutral gas
contained in DLAs and in systems with lower column density. Whilst in the
redshift range 2 to 3.5, ~90% of the neutral HI mass is in DLAs, we find that
at z>3.5 this fraction drops to only 55% and that the remaining 'missing' mass
fraction of the neutral gas lies in sub-DLAs with N(HI) 10^{19} - 2 * 10^{20}
atom/cm^2. The characteristic column density, N_*, changes from 1.6 * 10^{21}
atom/cm^2 at z3.5, supporting a picture
where at z>3.5, we are directly observing the formation of high column density
neutral hydrogen DLA systems from lower column density units. Moreover since
current metallicity studies of DLA systems focus on the higher column density
systems they may be giving a biased or incomplete view of global galactic
chemical evolution at z>3. After correcting the observed mass in HI for the
``missing'' neutral gas the comoving mass density now shows no evidence for a
decrease above z=2. (abridged)Comment: Replaced to match version published in MNRAS. One figure and appendix
added, analysis and conclusions unchange
A Novel Mutation in the Upstream Open Reading Frame of the CDKN1B Gene Causes a MEN4 Phenotype
PubMed ID: 23555276This is an open-access article distributed under the terms of the Creative Commons Attribution License, which permits unrestricted use, distribution, and reproduction in any medium, provided the original author and source are credited
The State of Sustainable Markets 2021: Statistics and Emerging Trends
This sixth global report provides new insights into the evolution of certified agriculture and forestry. The International Trade Centre has teamed up once again with the Research Institute of Organic Agriculture and the International Institute for Sustainable Development to provide data about 14 major sustainability standards for bananas, cocoa, coffee, cotton, oil palm, soybeans, sugarcane, tea and forestry products.
The 2021 report adds data from 2019, showing that sustainability standards continue to expand their land coverage. This report helps shape decisions of policymakers, producers and businesses, working to address systemic labour and environmental challenges through certified sustainable production
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