6,193 research outputs found
Recommended from our members
Child Education and Work Choices in the Presence of a Conditional Cash Transfer Programme in Rural Colombia
The paper studies the effects of Familias en Acción, a conditional cash transfer program implemented in rural areas in Colombia since 2002, on school enrolment and child labour. Using a difference-in-difference framework, our results show that the program increased school participation of 14 to 17 year old children quite substantially, by between 5 and 7 percentage points, and had lower effects on the enrolment of younger children, in the region of 1 to 3 percentage points. The effects on work are largest in the relatively more urbanised parts of rural areas and particularly for younger children, whose participation in domestic work decreased by around 13 percentage points after the program, as compared to a decrease of 10 percentage points for older children in these same areas. The program had no discernible impacts on children’s work in more rural areas. Participation in income-generating work remained largely unaffected by the program. We also find evidence of school and work time not being fully substitutable, suggesting that some, but not all, of the increased time at school may be drawn from children’s leisure time
Spatio-temporal expression patterns of Arabidopsis thaliana and Medicago truncatula defensin-like genes
Plant genomes contain several hundred defensin-like (DEFL) genes that encode short cysteine-rich proteins resembling defensins, which are well known antimicrobial polypeptides. Little is known about the expression patterns or functions of many DEFLs because most were discovered recently and hence are not well represented on standard microarrays. We designed a custom Affymetrix chip consisting of probe sets for 317 and 684 DEFLs from Arabidopsis thaliana and Medicago truncatula, respectively for cataloging DEFL expression in a variety of plant organs at different developmental stages and during symbiotic and pathogenic associations. The microarray analysis provided evidence for the transcription of 71% and 90% of the DEFLs identified in Arabidopsis and Medicago, respectively, including many of the recently annotated DEFL genes that previously lacked expression information. Both model plants contain a subset of DEFLs specifically expressed in seeds or fruits. A few DEFLs, including some plant defensins, were significantly up-regulated in Arabidopsis leaves inoculated with Alternaria brassicicola or Pseudomonas syringae pathogens. Among these, some were dependent on jasmonic acid signaling or were associated with specific types of immune responses. There were notable differences in DEFL gene expression patterns between Arabidopsis and Medicago, as the majority of Arabidopsis DEFLs were expressed in inflorescences, while only a few exhibited root-enhanced expression. By contrast, Medicago DEFLs were most prominently expressed in nitrogen-fixing root nodules. Thus, our data document salient differences in DEFL temporal and spatial expression between Arabidopsis and Medicago, suggesting distinct signaling routes and distinct roles for these proteins in the two plant species
Two planetary systems with transiting Earth-size and super-Earth planets orbiting late-type dwarf stars
We present two new planetary systems found around cool dwarf stars with data
from the K2 mission. The first system was found in K2-239 (EPIC 248545986),
char- acterized in this work as M3.0V and observed in the 14th campaign of K2.
It consists of three Earth-size transiting planets with radii of 1.1, 1.0 and
1.1 R Earth, showing a compact configuration with orbital periods of 5.24, 7.78
and 10.1 days, close to 2:3:4 resonance. The second was found in K2-240 (EPIC
249801827), characterized in this work as M0.5V and observed in the 15th
campaign. It consists of two transiting super-Earths with radii 2.0 and 1.8 R
Earth and orbital periods of 6.03 and 20.5 days. The equilibrium temperatures
of the atmospheres of these planets are estimated to be in the range of 380-600
K and the amplitudes of signals in transmission spectroscopy are estimated at
~10 ppm.Comment: Accepted for publication in MNRAS letter
F-algebra–Rinehart pairs and super F-algebroids
We define F-algebra--Rinehart pairs and super F-algebroids and study theconnection between them.<br
ABJM Baryon Stability and Myers effect
We consider magnetically charged baryon vertex like configurations in AdS^4 X
CP^3 with a reduced number of quarks l. We show that these configurations are
solutions to the classical equations of motion and are stable beyond a critical
value of l. Given that the magnetic flux dissolves D0-brane charge it is
possible to give a microscopical description in terms of D0-branes expanding
into fuzzy CP^n spaces by Myers dielectric effect. Using this description we
are able to explore the region of finite 't Hooft coupling.Comment: 29 pages, Latex; minor changes; version to appear in JHE
An RxLR effector from phytophthora infestans prevents re-localisation of two plant NAC transcription factors from the endoplasmic reticulum to the nucleus
The plant immune system is activated following the perception of exposed, essential and invariant microbial molecules that are recognised as non-self. A major component of plant immunity is the transcriptional induction of genes involved in a wide array of defence responses. In turn, adapted pathogens deliver effector proteins that act either inside or outside plant cells to manipulate host processes, often through their direct action on plant protein targets. To date, few effectors have been shown to directly manipulate transcriptional regulators of plant defence. Moreover, little is known generally about the modes of action of effectors from filamentous (fungal and oomycete) plant pathogens. We describe an effector, called Pi03192, from the late blight pathogen Phytophthora infestans, which interacts with a pair of host transcription factors at the endoplasmic reticulum (ER) inside plant cells. We show that these transcription factors are released from the ER to enter the nucleus, following pathogen perception, and are important in restricting disease. Pi03192 prevents the plant transcription factors from accumulating in the host nucleus, revealing a novel means of enhancing host susceptibility
BCR-ABL1-induced expression of HSPA8 promotes cell survival in chronic myeloid leukaemia
In order to determine new signal transduction pathways implicated in
chronic myeloid leukaemia (CML), we performed a gene expression profile
comparison between CD34+ cells from CML patients and healthy donors.
Functional studies were performed using the Mo7e and Mo7e-p210 cell lines.
Expression of CCND1 (Cyclin D1), as well as the chaperone HSPA8, which is
important for regulation of CCND1, were significantly upregulated in CD34+
CML cells. Upregulation of HSPA8 was dependent, at least in part, on STAT5
(signal transducer and activator of transcrition 5)-dependent transcriptional
activation, as demonstrated by chromatin immunoprecipitation. The
presence of HSPA8 in the nuclear protein fraction as well as its binding to
CCND1 suggests that it may contribute to stabilization of the CCND1/CDK4
complex, which, in turn, may participate in proliferation of CML
cells. Treatment of CML cells with the specific HSPA8 inhibitor
15-deoxyspergualin induced inhibition of CML cell viability but did not
induce apoptosis. In conclusion, our studies suggest that STAT5-mediated
activation of HSPA8 induces nuclear translocation and activation of the
CCND1/CDK4 complex leading to increased proliferation of CML cells,
deciphering a new pathway implicated in CML and supporting a potential
role of chaperone inhibitors in the treatment of CML
- …
